Ophthalmology Review

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July 31, 2005

Ophthalmologists may be first to spot elder abuse

Ophthalmology times July 2005
Elder abuse is defined as the willful infliction of pain, injury, or mental anguish on an older individual,"

Dr. Miller highlighted the risk factors for elder abuse and what to look for during a physical examination.

Dr. Miller highlighted the risk factors for elder abuse and what to look for during a physical examination.

He noted that elder abuse falls into seven categories
.Physical abuse—not the most common form of elder abuse—involves .
.forced restraints and hitting.
.Unwanted sexual contact.
.Psychological abuse (i.e., intimidation, humiliation).
.Financial exploitation.
.Self-neglect—failure of an individual to provide appropriate self-care to avoid harm or injury.
.Abandonment

Ophthalmologic signs. "Ophthalmologists may recognize the pres- ence of dehydration; sunken eyes; scalp, facial, or neck ecchymoses; abrasions; burns or lacerations; recent trauma to the eyes reflected in subconjunctival or vitreous hemorrhages; traumatic cataract, retinal detachment, or orbital fractures; and more commonly, individuals may have broken their glasses and do not have a full explanation of why it happened," Dr. Miller said. "In addition, there may be an inadequate response to what should be a straightforward medical treatment for a problem or noncompliance to a prescribed treatment regimen.

Posted by aman at 11:40 PM | Comments (0)

Tissue-engineered cornea for refractive correction, transplantation may be reality

Oopthalmology times July 2005
Washington, DC—Researchers focusing on developing a tissue-engineered (TE) cornea for use in transplantation or refractive correction have made significant progress, although a number of challenges still lie ahead, said May Griffith, PhD, at World Cornea Congress V.
Mimic human properties Designers of a TE cornea are aiming to mimic all of the properties of the human cornea in order to produce a product that offers transparency, suturability, and acts as a tough barrier against infection and injury. In addition, it must be biocompatible, and it should integrate seamlessly into host tissue while being able to promote repair and regeneration of the host cornea.
In creating a TE cornea, Dr. Griffith and colleagues have been using natural materials (collagen) that are present within the human cornea matrix to replace the scaffolding of the damaged or diseased cornea and adding synthetic materials for reinforcement along with bioactive factors, such as cytokines and growth factors, to enable host integration. The cellular components of the cor-nea are expected to come from the host or to be jump started with stem cells if necessary.
"Compared with the human corneal matrix, TE corneal implants have been created that have almost the same refractive index and offer identical transmission and backscatter properties," Dr. Griffith explained. "These materials exhibit glucose permeability, can be ablated with the excimer laser, are biocompatible, support wound healing and regeneration, and, thanks to the addition of bioactive peptides, can offer the opportunity for more rapid re-innervation compared with the human cornea."

Posted by aman at 11:24 PM | Comments (0)

Is optic neuritis more benign than other first attacks in multiple sclerosis?

AJO MAY 2005
Multiple sclerosis (MS) often presents with isolated optic neuritis; indeed, a number of patients with isolated optic neuritis eventually develop definite MS. Natural history studies have suggested that such forms of MS may have a better prognosis than those presenting with brainstem syndromes or myelitis. The goal of this study was to compare the rate of conversion with definite MS based on the first clinical presentation (isolated optic neuritis, brainstem syndrome, or myelitis). The authors prospectively evaluated 320 patients with a clinically isolated syndrome (123 with optic neuritis, 78 with brainstem syndromes, 89 with spinal cord syndromes, and 30 with other topographies) who were observed for a median of 39 months. Patients underwent a brain MRI within 3 months of their first attack and again 12 months later. Conversion to MS, determined either clinically or by MRI, was evaluated according to topography. Baseline MRI was normal in 49.2% of patients with optic neuritis compared with 24% of patients with brainstem syndromes, 24% of patients with spinal cord syndromes, and 18.5% of patients with other syndromes. Optic neuritis patients had a lower conversion to clinically definite MS and a smaller proportion of patients fulfilling MRI dissemination in space, time, or both. Nevertheless, when only patients with abnormal cranial MRI results at baseline were selected, no differences for clinical or MRI conversion were found. The authors conclude that even though optic neuritis patients have a smaller risk for conversion to MS, it is the MRI at baseline, not the clinical presentation, which determines the subsequent risk of definite MS. —Valérie Biousse

Posted by aman at 03:46 AM | Comments (0)

Staphylococcus hominis Endophthalmitis Associated With a Capsular Hypopyon

AJO MAY 2005
A 51-year-old man presented with chronic postcataract extraction inflammation and underwent vitrectomy, partial capsulectomy, and intravitreal antibiotic injections, followed by explantation of the intraocular lens and capsule.
A capsular hypopyon in the absence of an anterior chamber hypopyon was noted. Cultures of the vitreous and capsule revealed Staphylococcus hominis, a coagulase-negative gram-positive organism.

Conclusions
We are unaware of previous reports of endophthalmitis caused by Staphylococcus hominis, and could find none in a computerized search using MEDLINE. This case adds Staphylococcus hominis to the list of causative organisms in chronic endophthalmitis and illustrates the rare finding of a capsular hypopyon

Posted by aman at 03:41 AM | Comments (0)

Lash Ptosis Caused by Latanoprost

AJO MAY 2005
A 61-year-old, ocular hypertensive man who was using latanoprost OU presented with trichomegaly and bilateral lash ptosis. The lash ptosis had not resolved 6 months after stopping latanoprost, and anterior lamellar repositions were performed. At last follow-up, 8 months after surgery, the lids were in a normal position, but the trichomegaly had reduced only slightly.

Conclusions
Lash ptosis should be considered as a possible complication of latanoprost therapy

Posted by aman at 03:35 AM | Comments (0)

Extensive Upper-extremity Venous Thrombosis After Fluorescein Angiography

AJO MAY 2005
A 38-year-old Chinese male presented with blurring of vision in his left eye. Clinical examination revealed central serous retinopathy, and a routine fluorescein angiography was performed.
Results
He developed inflammation over the right arm over 4 days. Duplex scan disclosed extensive superficial venous thrombosis of the right upper limb with occlusion of the basilic vein and cephalic vein in the proximal right upper arm to the level of the midarm. He was treated medically but was subsequently lost to follow-up.

Conclusions
Extensive upper-extremity venous thrombosis is infrequent after single-shot intravenous cannulation. Venous thrombosis occurring after fluorescein angiography has not been reported up to this time. It is possible that proper arm positioning during the procedure may reduce this risk, and ophthalmologists should be vigilant of this potentially unusual complication

Posted by aman at 03:30 AM | Comments (0)

Use of Surodex in Phacotrabeculectomy Surgery

AJO MAY 2005
To evaluate the use of Surodex (Oculex Pharmaceuticals, Sunnyvale, California) a drug delivery system incorporating 60 micrograms of dexamethasone in a pellet, in phacotrabeculectomy surgery.
Methods
Phacotrabeculectomy was performed on 37 Asian subjects with primary open-angle glaucoma (POAG) using a standardized technique. All subjects received a Surodex pellet underneath the scleral flap. Results were compared with those of 31 POAG subjects who had undergone phacotrabeculectomy augmented with 50 mg/ml of intraoperative 5-fluorouracil (5-FU) during the same period.

Results
Mean follow-up in months was 19.7 ± 7.9 and 22.1 ± 6.2 for the Surodex and 5-FU groups, respectively (P = .29). There was a 20.1% decrease in intraocular pressure in the Surodex group compared with 28.5% decrease in the 5-FU group (P = .6). Postoperative complications occurred in three cases (8.1%) and six cases (19.3%), respectively (P = .04).

Conclusions
Combined phacotrabeculectomy surgery augmented by intra-scleral placement of Surodex results in good control of IOP and a low incidence of complications

Posted by aman at 03:22 AM | Comments (0)

Fuchs Heterochromic Cyclitis and Ocular Toxocariasis

AJO MAY 2005
To report the association of Fuchs heterochromic cyclitis (FHC) and ocular toxocariasis in a young adult

A 26-year-old patient was referred for the management of a unilateral intermediate uveitis associated with a lower peripheral subretinal fibrotic lesion near the pars plana. Diagnosis of FHC was clinically confirmed. Laboratory examination was performed to exclude an infectious condition.

Results
LISA assay detected significant levels of IgG directed against Toxocara canis. Toxoplasmic serology was negative, excluding this differential diagnosis. Other examinations, including complete blood cell count, urinalysis, serum angiotensin-converting enzyme, lysosyme, chest CT scan, and syphilis serology were noncontributive.

Conclusions
Previous studies have reported on the association of FHC and other parasitic conditions, such as toxoplasmosis but also on herpetic ocular infections. Serologic analysis for toxocariasis may be proposed in patients with FHC and retinal scars in the absence of toxoplasmosis

Posted by aman at 03:10 AM | Comments (0)

Pigmented-membrane Formation on Acrylic Intraocular Lenses After Phacoemulsification

AJO MAY 2005
To report the formation of pigmented membranes on acrylic intraocular lenses (IOLs) after phacoemulsification and to determine the clinical characteristics of these pigmented membranes.
Methods
Four eyes of three patients were found to have pigmented membranes on their acrylic IOLs (Sensar AR40). Their medical records were reviewed.

Results
The pigmented membranes were observed at 4- to 9-month intervals after phacoemulsification. Their best-corrected Snellen visual acuity (BCVA) decreased by more than 2 lines, ranging from 20/63 to 20/40. After Nd:YAG laser treatment, BCVA improved 2 to 4 lines. At 5- to 12-week intervals after Nd:YAG laser treatment, recurrences of the pigmented membranes were observed with decreased BCVA.

Conclusions
We have observed visually significant, recurrent, pigmented membrane formation in eyes implanted with Sensar AR40 acrylic IOLs. To the best of our knowledge, pigmented membranes on acrylic IOLs have not been described previously

Posted by aman at 03:02 AM | Comments (0)

Heavy Metal Concentrations in Human Eyes

AJO MAY 2005
To measure the concentration of toxic heavy metals in the fluids and tissues of human eyes
Thirty autopsy eyes of 16 subjects were dissected to obtain the aqueous, vitreous, lens, ciliary body, retina, and retinal pigment epithelium/choroid. Concentrations of lead, cadmium, mercury, and thallium in ocular tissues, ocular fluids, and blood were determined using an inductively coupled plasma-mass spectrometer and expressed as ng/g. Heavy metal concentrations in ocular tissues were compared using a paired t test.

Conclusions
Lead and cadmium accumulate in human ocular tissues, particularly in the retinal pigment epithelium and choroid. The potential ocular toxicity of these heavy metals and their possible role in eye disease requires further study

Posted by aman at 02:47 AM | Comments (0)

Choosing the Location of Corneal Incision Based on Preexisting Astigmatism in Phacoemulsification

AJO MAY 2005
To investigate the best location of clear-cornea incision in phacoemulsification, depending on preexisting corneal astigmatism.
A total of 574 patients in five stages were assigned to the following incisions: superior or temporal (n = 89), superior (n = 141), superior or superior plus relaxing (n = 102), nasal or temporal (n = 156), and incisions based on applying conclusions of preceding and current studies (n = 86). Visual acuity, refraction, biomicroscopy, keratometry, and videokeratography (Fourier analysis) were performed before and after phacoemulsification and intraocular lens implantation (3.5-mm incision). main outcome measures: Corneal refractive and surface regularity index change between preoperative and 6-month postoperative examination. Visual acuity at 6 months.
Conclusions
Superior incision is recommended with at least 1.5 diopters of astigmatism and steep axis at 90 degrees. Temporal incision is recommended with astigmatism < 1.5 diopters and steep axis at 90 degrees, negligible astigmatism, or astigmatism < 0.75 diopters and steep axis at 180 degrees. Nasal incision is recommended with at least 0.75 diopters of astigmatism and steep axis at 180 degrees

Posted by aman at 02:23 AM | Comments (0)

Use of Progressive Glaucomatous Optic Disk Change as the Reference Standard for Evaluation of Diagnostic Tests in Glaucoma

AJO June 2005
Progressive change in optic disk appearance has been suggested as the best available reference standard for glaucoma diagnosis. We evaluated the accuracy of scanning laser polarimetry (SLP) with variable corneal compensation to discriminate patients with documented progressive optic disk change from healthy subjects.

Glaucoma patients with documented evidence of progressive optic disk change as assessed by stereoscopic photographs were selected. Healthy control subjects had normal visual fields and normal clinical examination. All subjects underwent imaging with the GDx VCC scanning laser polarimeter. Receiver-operating characteristic (ROC) curves, sensitivities at fixed specificities, and likelihood ratios were calculated.

Results
Sixty-five eyes were healthy control patients. Seventy-one eyes had progressive optic disk change, of which 41 (58%) had abnormal visual field tests closest to the imaging date (perimetric glaucomatous optic neuropathy [GON]), and 30 (42%) eyes had normal visual fields (preperimetric GON). The GDx VCC parameter nerve fiber indicator performed best for discrimination between perimetric GON and normal eyes (AUC = 0.94; sensitivity = 93% for specificity ≥80%) as well as for the discrimination between preperimetric GON and normal eyes (AUC = 0.89; sensitivity = 83% for specificity ≥80%).

Conclusion
SLP differentiated patients with documented progressive optic disk change from normal subjects and detected abnormalities in patients with confirmed diagnosis of preperimetric GON, suggesting that it may be useful for early glaucoma diagnosis. We suggest that progressive optic disk change should be used in the evaluation of diagnostic accuracy of imaging instruments for glaucoma.

Posted by aman at 02:09 AM | Comments (0)

Nerve Growth Factor Concentration and Implications in Photorefractive Keratectomy vs Laser In Situ Keratomileusis

AJO June 2005
To determine whether tear nerve growth factor (NGF) concentration correlates with corneal sensation and ocular surface dryness after photorefractive keratectomy (PRK) and laser in situ keratomileusis
(LASIK).
Seventy eyes of 35 patients and 76 eyes of 38 patients underwent PRK and LASIK procedures to correct myopia and myopic astigmatism, respectively. Total tear protein level, tear NGF concentration, tear film breakup time (BUT) and Schirmer values were measured before and 1 day, 1 week, 1 month, 3 months, and 6 months after surgery.

Results
The postoperative mean tear NGF/total tear protein (NGF/tP) ratio increased in both PRK and LASIK patients compared with preoperative levels (P < .0001). At 1 week and 1 month postoperatively, the NGF/tP ratio was higher in PRK than in LASIK subjects (P < .0001). Before 6 months postoperatively, the mean corneal sensation after LASIK in the ablated zone was lower than the preoperative sensation (P < .0001), but this was not the case in PRK subjects. Mean BUT and Schirmer values were significantly lower in LASIK-treated eyes compared with PRK-treated eyes up to 6 months postoperatively (P < .0001). The early postoperative tear NGF/tP ratio correlated with the postoperative 6-month value of corneal sensation, BUT, and Schirmer values.

Conclusions
The difference in the postoperative corneal sensation and ocular surface dryness between PRK-treated and LASIK-treated eyes might be related to the difference in the early postoperative levels of NGF, which is a potent nerve growth stimulator

Posted by aman at 01:52 AM | Comments (0)

July 30, 2005

Paraneoplastic optic neuropathy in a patient with a non-small cell lung carcinoma: A case report

EJO MAY-June 2005
To report a case and describe the clinical approach to a patient with a non-small cell lung carcinoma and paraneoplastic optic neuropathy
Methods. Case report.
Results. A 79-year-old woman with known non-small cell lung carcinoma was admitted with a swollen optic disc in the right eye. After detailed clinical, laboratory, and imaging studies, the authors diagnosed paraneoplastic optic neuropathy, excluding other possible diagnosis.
Conclusions. Paraneoplastic optic neuropathy is a clinical challenge and should be considered as a possible diagnosis in every cancer patient with optic disc edema

Posted by aman at 11:16 PM | Comments (0)

A novel index for predicting intraocular pressure reduction following cataract surgery

BJO 2005 TOP TEN Link
Aim: The results of a study designed to investigate the predictive value of preoperative anterior chamber depth (ACD) and intraocular pressure (IOP) are reported. The relation between these factors and their effect on the reduction in IOP following phacoemulsification cataract surgery was also studied.

Methods: The ACD and IOP were prospectively measured in 103 non-glaucomatous eyes of 103 patients who underwent uneventful phacoemulsification and posterior chamber intraocular lens (PCIOL) implantation. Other data which were recorded included best corrected visual acuity, axial length, lens thickness, and severity of lens opacity.

Results: The ACD increased by a mean (SD) of 1.10 (0.44) mm (p<0.00001) and this increase was significantly and inversely related to preoperative ACD (r2 = 68%; p<0.01). IOP dropped by a mean of 2.55 (1.78) mm Hg following cataract surgery (p<0.0001), and this reduction was significantly and positively related to preoperative IOP (r2 = 56%; p<0.01), and significantly and inversely related to preoperative ACD (r2 = 21%; p<0.01). A novel ratio, the pressure to depth (PD) ratio (preoperative IOP/preoperative ACD), was found to be significantly and positively related to the surgically induced reduction in IOP (r2 = 73%; p<0.01), and IOP was reduced by 4 mm Hg in all patients with a PD ratio >7.

Conclusion: The reduction in IOP following cataract surgery was found to be positively related to preoperative IOP, and inversely related to preoperative ACD. Furthermore, these results indicate that a novel index, the PD ratio, is strongly predictive for IOP reduction following cataract extraction, and may prove useful in surgical decision making

Posted by aman at 11:10 PM | Comments (0)

Migration of Intraocular Silicone Into the Cerebral Ventricles

AJO July 2005
A 62-year-old woman presented with proliferative diabetic retinopathy and tractive retinal detachment in her left eye. Par plana vitrectomy and injection of 5,000-centistoke-viscosity silicone oil were performed. Intraocular pressure was elevated after the operation and poorly controlled for 4 months. Eight months after the first operation, the patient felt dizzy. Computed tomography (CT), magnetic resonance imaging (MRI), and optical coherence tomography (OCT) scanning were performed.

Results
The CT imaging, MRI, and OCT showed silicone oils migrated into the sella cistena superioris and the cerebral ventricles. Follow-up examination was continued.

Conclusion
Although silicone oil migrating into the ventricles is unusual, we suggest that every patient undergoing silicone oil tamponade with poorly controlled high intraocular pressure and optic disk atrophy should be carefully evaluated

Posted by aman at 01:56 AM | Comments (0)

Optic disc signs good predictors of glaucoma risk

OSN 3/17/2005
Optic disc changes can be a good indicator of the risk of glaucoma development in a patient, according to data from an Australian population-based study.

Paul Mitchell, MD, PhD, and colleagues analyzed data from the Blue Mountains Eyes Study to determine the 5- and 10-year incidences of open-angle glaucoma. Dr. Mitchell said 1,667 people were included in both analyses. He described the study results here at the Moorfields Bicentenary scientific meeting.

The 10-year incidence of open-angle glaucoma in the study population was 2.94%. The incidence was higher for women (3.78%) than for men(1.74%), Dr. Mitchell said. Age was also a factor in the incidence of open-angle glaucoma, with a 16.7% incidence rate in those older than 85 at the 10-year mark vs. 15% for those between 50 and 59 at the 10-year mark.

Peripapillary atrophy was also a significant risk factor; presence of peripapillary atrophy at baseline was associated with a threefold increase of risk for glaucoma development or progression at 10 years. Another risk factor, the presence of disc hemorrhage at baseline, was associated with a tenfold increase in likelihood of glaucoma progression or development at the 5- and 10-year follow-ups, Dr. Mitchell said.

“Family history, IOP, ocular hypertension and disc hemorrhage all increase the risk of developing glaucoma,” he said.

Overall, 16.3% of those with ocular hypertension (defined as an IOP of more than 21 mm Hg) developed open-angle glaucoma by year 10. Likewise, 31.3% of patients with disc hemorrhage at baseline developed open-angle glaucoma by year 10.

Dr. Mitchell noted that the rates of disc hemorrhage in this subset of the Blue Mountains Study were higher than in other population-based studies, “but I think they’re underestimated,”

Posted by aman at 01:47 AM | Comments (0)

Age, ethnicity are factors in rate of myopia progression, axial elongation

OSN 7/29/2005
The speed of myopia progression and axial elongation are affected by ethnicity and age, according to a recent study.

Leslie Hyman, PhD, and colleagues analyzed data from the Correction of Myopia Evaluation Trial to identify the baseline factors independently related to 3-year myopia progression and axial elongation. In the COMET, 469 myopic children were randomly assigned to progressive addition lenses or single vision lenses.

“Younger baseline age was the strongest factor independently associated with faster myopic progression and greater axial elongation at 3 years,” the researchers said.

The children enrolled in the study were 6 to 11 years old and had spherical equivalent myopia ranging from –1.25 to -4.50 D bilaterally.

The study found that 6- and 7-year-old children had the fastest rate of myopia progression of all age groups, progressing by a mean of 1.31 D more than the 11-year-old children.

The researchers also found that black children had less myopic progression and axial elongation than children of mixed, Hispanic, Asian or white ethnicity

Posted by aman at 01:09 AM | Comments (0)

Outcome of Therapeutic Penetrating Keratoplasty in Infectious Keratitis

OPHTHALMIC SURGERY, LASERS AND IMAGING July/August 2005

prospective database on 134 therapeutic cornea transplants in 134 patients recorded demographic details on age and gender of the patient, indication for surgery, size of the donor and recipient bed, graft clarity, complications, and residual morbidity. Patients included in this analysis had a minimum follow-up of 1 year. All patients underwent therapeutic penetrating keratoplasty by a similar method that involved a donor button that was oversized by 0.5 mm and 16 bites of interrupted sutures.

RESULTS
Most of the 134 ulcers needing therapeutic grafts were bacterial (n = 54) or fungal (n = 54). One hundred eighteen eyes had perforation at presentation. One hundred six (90%) of the therapeutic grafts achieved anatomical success. The most common complication of glaucoma occurred in 22% of eyes with presurgical perforated ulcers and 1% of nonperforated ulcers. Persistent epithelial defects were significantly more frequent in grafts of 9 mm or more (P = .05).

CONCLUSIONS
Our results confirm that therapeutic penetrating keratoplasty for infections is successful in restoring anatomic integrity in most eyes.

Posted by aman at 12:57 AM | Comments (0)

Cortical cataracts have genetic link , posterior subcapsular cataracts do not, study finds

OSN TOP STORIES 2/11/2005
Genetics have a significant effect on the development of cortical cataracts, but not posterior subcapsular cataracts, a study by researchers at Johns Hopkins University suggests.

Nathan Congdon, MD, MPH, and colleagues conducted a study to quantify the risk of development of age-related cortical cataract or posterior subcapsular cataract (PSC) in a person who has a sibling with cataract.

The researchers studied 321 participants already enrolled in the Salisbury Eye Evaluation (SEE) study and compared results with 453 of their siblings. The siblings had a mean age of 72.6, while the study participants had a mean age of 78 years. The difference in mean age was statistically significant.

After adjusting for environmental factors such as use of tobacco and alcohol, use of medications such as estrogens and steroids, lifetime exposure to ultraviolet-B light, serum antioxidants, history of diabetes, blood pressure and body mass index, the researchers found that cortical cataract had a magnitude of heritability of 24%. The magnitude of heritability of PSC, 4%, was not statistically significant.

Older age, female gender, history of diabetes and black race increased the odds of cortical cataract development; higher levels of provitamin A were found to be protective. Diabetic history and steroids increased the odds of PSC development

Posted by aman at 12:40 AM | Comments (0)

Is CK effective?

OCULAR SURGERY NEWS July 15, 2005
Royal Hawaiian Eye Meeting 2005 Symposium
Daniel S. Durrie, MD
In the FDA presbyopic clinical trial, CK was performed in 188 eyes of 150 subjects with a mean age of 53.3 The mean intended correction was 1.58 D ± 0.67 D, with a correction range of 0.75 D to 3 D.4 Results were recorded at 1, 3, 6, 9, 12 and 24 months postoperatively.

Testing at 6 months postoperatively showed 85% of all patients had binocular distance vision uncorrected visual acuity (UCVA) of 20/20 or better along with J3 or better near vision. Also at 6 months postoperatively, 86% of patients had manifest refractive spherical equivalent (MRSE) changes of ± 0.50 D between 3 and 6 months postoperatively.5

Also at 6 months postoperatively, patients experienced improvements in their ability to read computer screens, menus, newspapers, magazines and fine print without glasses. According to patients surveyed, distance vision, as well as near vision, improved. No contrast sensitivity was lost between preoperative best spectacle-corrected visual acuity (BSCVA) and postoperative UCVA at distance. Depth perception was maintained and patient satisfaction was also high.4 At 12 months, 98% of patients noted improvement in quality of vision and 84% were “satisfied” or “very satisfied” with CK results

Additional findings – my personal CK results
To determine if and how long CK results were maintained, I tested nine patients who participated in the FDA trial at 12 through 26 months postoperatively (Figure 2). Compared to preoperatively, these patients gained on average 7.1 ± 2.9 lines in near UCVA in the CK-corrected nondominant eye. No change was seen in the untreated dominant eye. Patients also gained 0.33 ± 1.7 lines in distance UCVA in the treated eye and experienced no change in the dominant eye. The 7-line gain in near vision and the slight gain in distance vision led to high patient satisfaction.

Posted by aman at 12:13 AM | Comments (0)

July 29, 2005

Dynamic contour tonometry measurements reliable for all corneal thicknesses

Eurotimes July 2005
In one study, UK researchers compared IOP measurements with dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT) to evaluate how well the two technologies agreed when the effects of central corneal thickness (CCT) and patient age were taken into
account
The Moorfields researchers did DCT and GAT measurements on
130 eyes of 130 patients.They used linear regression analysis to
determine the associations of IOP measurements with age and CCT.

The study found a significant relationship between GAT measurements and CCT and reported a 3.2 mmHg increase in IOP per 100 µm increase CCT.
With DCT, no such relationship was found.

“The differences between GAT and DCT also increased significantly with age, indicating that possibly age-related changes in corneal biomechanics may induce further measurementerror in the GAT.”

In another study, French researchers compared DCT and GAT results in 75 patients withthick, thin and normal range corneal thickness. Normal CCT was defined as 520 to 580
researchers compared DCT andmm; thin as less than 520 mm; and
thick as greater than 580 mm.
The researchers concluded thatin thin corneas, DCT might provide a more accurate IOP.They
provide a more accurate IOP.They noted that DCT may be useful for subjects with very reduced CCT but does not have any benefitover GAT in those with normalor increased CCT.

Posted by aman at 10:20 PM | Comments (0)

Light-touch technique offers potential for CK improvement

OCULAR SURGERY NEWS 7/1/2005

The 1-mm compression technique is still in early stages of use but has proven to cause less induced cylinder than conventional CK.

Initially described by H.L. Rick Milne III, MD, it involves making a 0.5 to 1 mm compression of the cornea with the keratoplasty tip during application of the radiofrequency energy. The dimple produced with CK with light touch is one-fifth to one-seventh the size of the corneal dimple produced in the conventional method, according to Dr. McDonald. Additionally, approximately 80% of patients need only eight treatment spots with CK with light touch vs. most needing 16- or 24-spot treatments with conventional CK.
“The inspiration came from a patient who had a shallow anterior chamber, and I did not want to compress his cornea,” Dr. Milne said in a follow-up interview with Ocular Surgery News. “At 1 week postop, he had a remarkably greater response compared to my patients that received conventional CK.
With conventional CK, the keratoplasty tip depresses the cornea and the foot pedal is pushed at the moment of maximal pressure, creating a dimple in the cornea and a light ring around the keratoplasty tip from 5 to 7 mm, Dr. McDonald explained. With CK with light touch, the surgeon barely touches the cornea, she said.“It’s easier to apply identical amounts of light pressure on the cornea than to produce identical amounts of extreme pressure on the cornea. In other words, with the conventional technique, there are certain positions with your hand where you’re probably not pressing as hard as others,” she said. “By just touching the cornea lightly when applying all CK treatment spots, which are now placed further from the visual axis, there’s less induced astigmatism.”

“Another advantage is that fewer treatment spots are needed to get a clinically significant effect, so when the patient returns in a couple of years [for a vision upgrade] there’s more space for additional touch-ups,” she added.

Dr. Milne said he believes the variability of compression between each spot is the key to cylinder.

Dr. McDonald advised instructing the patient to look at the fixation light during CK with light touch because otherwise the patient is able look away, whereas with conventional CK the patient is unable to move due to the pressure.

Dr. Milne’s technique is slightly different.

“I have the patients look at the fixation light only initially to get their eye into the right position, but then have them pretend to hold their eye still like they are a statue,” he said. “If they are trying to fixate on the light while the probe is being seated, then they will move their eye, because whenever the surgeon touches the cornea it makes the fixation light appear to move.”

Dr. McDonald emphasized that a steady hand position is important.

Although there is currently no proven nomogram for CK with light touch, some physicians who have been practicing the technique have been using Dr. Milne’s nomogram, according to Dr. McDonald.

Dr. Milne and Daniel S. Durrie, MD, pooled their data on light-touch CK to compare its efficacy to that of conventional CK (Figure). When comparing this limited data on CK with light touch to the Food and Drug Administration’s clinical trials data on conventional CK, the light-touch outcomes are better and are achieved with fewer spots, Dr. McDonald said.

In a side-to-side comparison of the pooled data with the CK FDA presbyopia clinical trials, she explained, the outcomes from CK with light touch are better than the conventional method in several ways, including the percentage that are within ±0.5 D of the intended outcome (85% vs. 63%); the percentage with no change in cylinder (90% vs. 71%); the percentage with less than 1 D of induced cylinder (6% vs. 17%); and the percentage with greater than 1 D of induced cylinder (4% vs. 12%).

Posted by alireza habibollahi at 08:18 PM | Comments (0)

Early Experiences with the New LADAR 6000(A better custom procedure due to automation, speed, and control)

EYEWORLD JULY 2005
The newest-generation platform in customized ablation, the LADAR™ 6000, provides an uncompromised wavefront-guided treatment. The system, which is CE marked in Europe and is currently being reviewed by the Food & Drug Administration for approval in the United States.
Enhanced illumination
The new illumination system is one of the hallmarks of LADAR 6000. The system is equipped with high-resolution cameras, surgeon-controlled lighting, infrared capabilities, and varied light colors for optimal visibility and control during the procedure. Illumination and the microscope on the LADAR 6000 are both 10 times better than with other lasers.
Automatic registration
The new auto-registration software on the LADARWave aberrometer saves time and greatly improves the consistency and efficiency of the registration process. Automatic registration enables the surgeon to match the measured wavefront with the eye during surgery. With automatic registration, the surgeon need only confirm that each of the five maps is captured from the same location.In the future, the new laser will employ a unique registration system that uses advanced infrared illumination and digital imaging to track blood vessels of the eye prior to surgery, to compensate for cyclotorsion, and to ensure accurate application of wavefront data. This will eliminate the need to mark the eye on the day of surgery to control for cyclotorsion.
Faster Ablation
the LADAR 6000 will also operate at a higher frequency, with more laser shots fired per second than the 4000. The new laser will likely approach 100 hertz and complete all procedures in a minute or less. “The faster you go, the less hydration issues may develop. Also, if I were able to cut the procedure time by 50%, I would be able to perform more surgeries in the same amount of time.”

Posted by mmiraftab at 09:29 AM | Comments (0)

Phlyctenular Keratitis Associated With Meibomitis in Young Patients

American Journal of Ophthalmology Volume 140, Issue 1 , July 2005, Pages 77-82

Of the 23 patients, 20 (87%) were women, and 13 (56.5%) had a history of chalazia. In all cases, the lesions and the severity of corneal nodules and neovascularization corresponded well with the location and the severity of meibomitis. The frequency of HLA-A26 and HLA-B35 was significantly increased in our patients (P = .003 and .016, respectively). Propionibacterium acnes in bacterial cultures of pure meibum in 12 of the 20 patients (60%) was statistically more highly positive than those in four of the 17 age-matched normal control subjects (23.5%; P = .028).
Conclusion
The characteristics of phlyctenular keratitis in our cases include significantly higher prevalence in female patients, severity variation of ocular surface manifestation corresponding to meibomitis, specific HLA association, and possible P. acnes involvement.

Posted by mmiraftab at 09:06 AM | Comments (0)

Corneal thickness not associated with eye length, study shows

OSN April 2005
Mitsugu Shimmyo, MD, and Paul Orloff, MD, of the Manhattan Eye, Ear and Throat Hospital, performed the study to investigate whether a thin cornea, which has been identified as a risk factor for glaucoma, might be associated with a weak sclera, an anatomic trait that might contribute to the vulnerability of the lamina cribrosa.

The researchers reviewed the charts of 1,084 eyes of 546 patients to determine correlations between central corneal thickness and axial length. The mean age of the patients was 66 years, ranging from 9 to 93 years. The review included 540 eyes of Hispanic patients, 215 eyes of Asian patients, 212 eyes of white patients and 117 eyes of black patients. Fewer than 10% of the eyes had glaucoma. All the eyes had central corneal thicknesses and axial length measured by ultrasonic pachymetry.

The mean central corneal thickness of all eyes was 543.1 µm, and the mean axial length was 23.44 mm.

The total patient study group showed no statistically significant association between central corneal thickness and axial length. A subgroup analysis by age, gender and race also failed to support an associative relationship

Posted by aman at 12:58 AM | Comments (0)

Argon Laser Peripheral Iridoplasty in the Management of Phacomorphic Glaucoma

OPHTHALMIC SURGERY, LASERS AND IMAGING July/August 2005
To document the efficacy and safety of argon laser peripheral iridoplasty (ALPI) as a temporizing measure in the treatment of phacomorphic glaucoma and to evaluate the mid-term visual outcomes.

PATIENTS AND METHODS
The clinical records of all patients with phacomorphic glaucoma treated with ALPI from December 1999 to December 2002 were retrospectively reviewed. The primary outcome measure was the rate of successful control of intraocular pressure. Successful cases with at least 12 months of follow-up were further analyzed regarding their outcomes after cataract surgery, including visual acuity, intraocular pressure (IOP), and angle status.

RESULTS
ALPI was performed as an initial step in the management of phacomorphic glaucoma in 21 eyes of 21 patients. IOP was successfully controlled in 17 eyes (80.75%), with a statistically significant decrease at 2 and 24 hours postoperatively (P < .0001). Elective cataract surgery was performed in 16 of the 17 successful cases and 12 of these patients completed at least 12 months of follow-up. After a mean follow-up period of 25.58 months, IOP was normal without medications in 11 eyes and only 1 patient required antiglaucoma eye drops to control IOP. All patients achieved a visual acuity of at least 1/60 and 8 (66.67%) of them achieved a visual acuity of 6/21 or better. All patients maintained an open angle without further surgical intervention. No complication was noted directly attributable to ALPI.

CONCLUSION
ALPI is a safe and efficacious measure for the initial management of phacomorphic glaucoma, simultaneously obviating the need to operate in highly inflamed eyes in an emergency setting and achieving satisfactory mid-term visual outcome

Posted by aman at 12:50 AM | Comments (0)

Study: Cataract surgery resolves persistent angle closure after iridotomy

OSN JULY 2005
Cataract surgery can relieve angle closure and lower elevated IOP that persists after iridotomy in Asian patients with primary angle-closure glaucoma, according to a study.

Atsushi Nonaka, MD, and colleagues at Kobe City General Hospital in Japan reviewed the records of 70 eyes with primary angle-closure glaucoma that were treated with laser iridotomy and identified 27 eyes (39%) with residual angle-closure. They treated 13 of these eyes with cataract surgery.

Main outcome measures included IOP levels, response to a dark-room prone-position test and morphologic analysis with ultrasound biomicroscopy. All were evaluated before and 3 months after cataract surgery. Eyes that had an IOP of at least 20 mm Hg or that had glaucomatous visual field defects before undergoing iridotomy had a significantly higher incidence of residual angle closure after iridotomy than eyes without a higher IOP or glaucomatous visual field defect.

“In this series of patients,” the study authors said in the June issue of Ophthalmology, “residual angle closure was common after laser iridotomy in eyes with primary angle closure, resulting in poor IOP control, especially in the advanced stages with elevated IOP or glaucomatous optic neuropathy. Cataract surgery subsequent to laser iridotomy was also effective for complete resolution of residual angle closure, which was due primarily to plateau iris, with concomitant lowering of IOP.”

In all of the eyes with residual angle closure after iridotomy, the response to the prone-position test became negative after cataract surgery, with significant lowering of IOP (P < .01).

Posted by aman at 12:28 AM | Comments (0)

Mitomycin in PRK can affect endothelial cell count

JRS APRIL 2005
WASHINGTON — Use of mitomycin-C in patients undergoing PRK can cause endothelial cell loss, as well as increased patient discomfort, according to Alberto J. Morales, MD.

Dr. Morales evaluated the effects of mitomycin 0.02% after PRK in 18 eyes of nine patients. All patients needed more than 75 µ of ablation depth and did not qualify for LASIK. He discussed his results here at the American Society of Cataract and Refractive Surgery meeting.

Endothelial cell counts were obtained preoperatively and at 1 and 3 months after PRK, Dr. Morales said. Patient discomfort was evaluated at 1 day and 1 week and at months 1 and 3.

Mitomycin-C (MMC) was applied to one eye of each patient for 30 seconds; the patient’s second eye received saline solution.

The eye that received MMC had significantly more discomfort as reported by the patient. Endothelial cells counts were “slightly reduced,” and corneal pachymetry was increased in the eyes receiving MMC compared with the eyes that had saline, he said.

“We are worried about the significant differences in endothelial cell loss with MMC,” he said.

Dr. Morales noted that these results are preliminary, and he said it is too early to determine the long-term effects of MMC. Longer follow-up is needed, and the researchers are considering evaluating more patients.

Dr. Morales’ presentation was awarded the Best Paper for the session

Posted by aman at 12:18 AM | Comments (0)

Implantation of Artisan Toric Phakic Intraocular Lenses for the Correction of Astigmatism and Spherical Errors in Patients With Keratoconus

JOURNAL OF REFRACTIVE SURGERY Vol. 21 No. 3 May/June 2005
Artisan toric PIOLs were implanted uneventfully in both eyes of three patients with keratoconus with clear central corneas and contact lens intolerance.

RESULTS
Best spectacle-corrected subjective visual acuity after lens implantation was unchanged in one eye and improved in five eyes. Spherical equivalent refraction was significantly reduced in all eyes (P=.03). The safety index was 1.49.

CONCLUSIONS
The implantation of an Artisan toric PIOL may be an alternative for treating astigmatism and myopia in contact lens intolerant patients with keratoconus with clear central corneas. Especially in patients with associated myopia, this procedure is worth considering before planning a penetrating keratoplasty.

Posted by aman at 12:09 AM | Comments (0)

Spontaneous Regression of Dense Epithelial Ingrowth After Laser in situ Keratomileusis

JOURNAL OF REFRACTIVE SURGERY Vol. 21 No. 3 May/June 2005
To present a case of dense epithelial ingrowth after laser in situ keratomileusis (LASIK) that spontaneously regressed 20 months after surgery.

METHODS
A 34-year-old woman underwent bilateral LASIK. On postoperative day 1, a large downward displacement of the flap in the right eye was observed. The flap was repaired; however, epithelial ingrowth from the flap edge was noted 1 month later at the 1, 5, 8, and 11 o’clock positions.

RESULTS
At 4-month follow-up, the epithelial ingrowth was stable at the 1, 8, and 11 o’clock positions but a dense sheet of epithelium was noted at the 5 o’clock position. At 15 months postoperatively, all epithelial ingrowth had resolved except for that at the 5 o’clock position. At 20 months postoperatively, the ingrowth at the 5 o’clock position had also regressed.

CONCLUSIONS
Dense epithelial ingrowth does not always require surgical intervention. Surgery is necessary only when the epithelium appears to be progressing, affects visual function, or causes flap melting

Posted by aman at 12:03 AM | Comments (0)

July 28, 2005

Management of Pellucid Marginal Degeneration With Intracorneal Ring Segments

JOURNAL OF REFRACTIVE SURGERY Vol. 21 No. 3 May/June 2005
A 41-year-old man with pellucid marginal degeneration with poor visual acuity due to irregular astigmatism was treated with Intacs microthin insert (KeraVision, Fremont, Calif) in the left eye.

RESULTS
Uncorrected visual acuity improved from 2/60 to 6/60 following the procedure. The procedure completely eliminated myopia of -8.00 diopters and improved the irregularity of the astigmatism, although it did not change its magnitude.

CONCLUSIONS
Insertion of the intracorneal ring segment improves visual acuity in pellucid marginal degeneration by flattening the central corneal protrusion, thus reducing myopia and improving the astigmatism irregularity
The authors have no proprietary interest in the materials presented herein.

Posted by aman at 11:59 PM | Comments (0)

Axial Eye Length Evaluation Before and After Myopic Photorefractive Keratectomy

JOURNAL OF REFRACTIVE SURGERY Vol. 21 No. 3 May/June 2005
To test the accuracy of a new device (IOL Master; Carl Zeiss, Jena, Germany) in detecting axial eye length changes after photorefractive keratectomy (PRK).
METHODS
Pre- and postoperative (1, 3, and 6 months) subjective refraction and axial eye length measurements were performed in 184 consecutive eyes that underwent PRK with the Nidek EC5000 excimer laser (Nidek Technologies, Gamagori, Japan) to treat refractive errors from -0.25 to -16.25 diopters (D) (mean: -5.12±3.01 D).

RESULTS
The axial eye length measurements ranged from 22.51 to 31.32 mm (mean: 25.61±1.47 mm) before PRK; from 22.39 to 31.10 mm (mean: 25.48±1.43 mm) 1 month after PRK; from 23.17 to 31.14 mm (mean: 25.61±1.36 mm) 3 months after PRK; and from 23.36 to 29.68 mm (mean: 25.58±1.35 mm) 6 months after PRK. Preoperative and 1-month postoperative data showed a statistically significant difference (P<.001), whereas no significant difference was found between 1 and 3 months (P=.0137) or 3 and 6 months (P=.2422).

CONCLUSIONS
The IOL Master showed a decrease in the axial eye length measurement larger than the theoretical ablation depth and the difference increased as the correction became higher

Posted by aman at 11:37 PM | Comments (0)

Rates of Epithelial Ingrowth After LASIK for Different Excimer Laser Systems

JOURNAL OF REFRACTIVE SURGERY Vol. 21 No. 3 May/June 2005
To investigate the incidence of epithelial ingrowth after laser in situ keratomileusis (LASIK) using the VISX 20/20B and VISX Star S3 laser systems.

METHODS
A chart review of patients who had undergone LASIK between April 1999 and December 2001 was performed. Patients having known risk factors for epithelial ingrowth were excluded from the study. Both eyes of patients who were operated with both laser systems were included in a paired analysis. The first operated eyes of the remaining patients were included in an unpaired analysis. The outcomes studied were epithelial ingrowth (a region of epithelial growth under the flap that was contiguous with the flap edge and extended at least 0.7 mm in the radial direction) and epithelial ingrowth requiring treatment (extending into the pupillary zone, causing reduced vision, causing nighttime glare, or inducing any melting of the flap edge).
RESULTS
In the paired study, 11 (61.1%) of 18 eyes treated with the VISX 20/20B had epithelial ingrowth, and 7 (38.9%) eyes required treatment. None of the eyes treated with the VISX Star S3 had epithelial ingrowth. In the unpaired study, 39 (37.1%) of 105 eyes treated with the VISX 20/20B were noted to have epithelial ingrowth and 14 (13.3%) eyes required treatment. None of the eyes treated with the VISX Star S3 had epithelial ingrowth. The incidence of epithelial ingrowth was significantly different for the VISX 20/20B and the VISX Star S3 in both analyses (paired: P<.001, McNemar's test; unpaired: P<.001, Fisher's exact test).

CONCLUSIONS
The laser system used in LASIK is a risk factor for the development of epithelial ingrowth. [J Refract Surg. 2005;21:276-280.]

Posted by aman at 11:23 PM | Comments (0)

Crystalline lens rise important in preventing pigment dispersion

OSN super site MAY 2005
Crystalline lens rise should be used as a safety criterion to prevent pigment dispersion in eyes with the Ophtec Artisan phakic IOL, according to a study. This should also apply to other types of phakic IOLs, the study authors noted.

Georges Baikoff, MD, and colleagues conducted a comparative analysis of crystalline lens rise in nine eyes that had pigment dispersion and 78 eyes that did not have dispersion. All 87 eyes had previous Artisan IOL implantation, and anterior segment imaging was performed with an anterior chamber optical coherence tomography prototype.

The study defined crystalline lens rise as the distance between the anterior pole of the crystalline lens and the horizontal plane joining the opposite iridocorneal recesses.

The researchers found that the higher the crystalline lens rise, the higher the risk of developing pigment dispersion. There was little or no risk of pigment dispersion with a rise of less than 600 µm, but 67% of eyes with a rise of 600 µm or more developed pupillary pigment dispersion. It was seen more frequently in hyperopic eyes than in myopic ones.

“In some cases in which the IOL was loosely fixated, there was no traction on the iris root and dispersion was prevented or delayed,” the researchers said.

Posted by aman at 11:17 PM | Comments (0)

July 26, 2005

Single dose of azithromycin effective against trachoma

OSN MAY 2005
In the study, prior to azithromycin treatment, swabs of the tarsal conjunctiva of each of the 978 village residents were collected to determine the prevalence and intensity of Chlamydia trachomatis infection in the community. After swabbing, 956 residents (97.8%) received either one oral dose of azithromycin or, if azithromycin was contraindicated, a course of tetracycline eye ointment. Swabs were then collected again at 2, 6, 12, 18 and 24 months after mass treatment.
According to the results, the prevalence of infection fell from 9.5% before mass treatment to 2.1% at 2 months and 0.1% at 24 months. The quantitative burden of ocular C. trachomatis infection in the community was 13.9% of its pretreatment level at 2 months and 0.8% at 24 months.

Posted by aman at 01:50 AM | Comments (0)

Large-Angle Strabismus and Primary True Muscle Transplantation

Journal of Pediatric Ophthalmology and Strabismus July/August 2005
Large-angle strabismus often demands a series of surgeries to achieve satisfactory alignment. This often necessitates bilateral surgery, which patients may be reluctant to undergo.
Three patients with large-angle esotropia, not amenable to standard recession and resection procedures, underwent primary true muscle transplantation wherein a fragment of resected extraocular muscle was used to elongate the medial rectus muscle.Postoperative deviation was within ± 10 PD of orthophoria and was maintained at follow-up of 6 to 12 months. There was mild underaction of the weakened muscle.
CONCLUSION:True muscle transplantation is a good option because it permits correction of large-angle strabismus with two-muscle surgery, provides a satisfactory cosmetic alignment, and appears safe and predictable.

Posted by afarahi at 01:41 AM | Comments (0)

Careful questions are key to successful strabismus treatment

TOP STORY for July 25, 2005

When presented with any type of pediatric strabismus, general ophthalmologists must listen carefully to parents and ask pointed questions before proceeding with a treatment regimen or surgery, according to a presenter here at the Argentinean Society of Ophthalmology’s Annual Course. Strabismus in its various forms can have important neurological implications. Also, conditions involving misalignment can be related to a systemic condition, Dr. Iurescia said. “When the parents come in and say, ‘My child’s eye drifts,’ pay close attention because surely it does,” . “Often during the exam, it is not easy to tell because the condition could be latent or intermittent or not manifesting itself for another reason.” Moreover, surgeons should consider the patient’s age in determining a course of action. For example, in infants younger than 1 year who present with exotropia, a neurological exam is imperative.Also, acute exotropia points to a systemic pathology and can be indicative of cerebral or tumoral disorders, she added.

Posted by afarahi at 01:30 AM | Comments (0)

Mushroom keratoplasty’ a promising option for corneal transplantation

OSN July 2005
A novel technique of corneal transplantation that combines the advantages of large lamellar grafts and penetrating keratoplasty can effectively treat full-thickness opacities with minimum removal of recipient endothelium, according to one surgeon.
The procedure, named “mushroom keratoplasty” by its creator, might be the best option for patients who have a normal, healthy endothelium but with central corneal scars and full-thickness opacities due to penetrating injuries, infections and degenerative disorders, according to Massimo Busin, MD.
Keratoconus patients may also benefit from this new approach, he added.

Surgery is carried out in two steps, Dr. Busin explained. First, a 9 mm wide and 200 µm thick superficial lamella – the mushroom’s head – is removed from the recipient’s eye by hand dissection. Next, a 5-mm trephine is used to make a circular incision in the center of the stroma, and a central button of stromal and endothelial tissue — the stem of the mushroom — is excised with scissors.

In the donor’s eye, a large corneal lamella 200 µm thick is dissected using a Moria ALTK microkeratome and then punched to size (9 mm) with a trephine. Using the same instrument, a 5-mm button is then removed from the remaining deep stroma and endothelial layer.

“We place the ‘mushroom stem’ in the central hole of the recipient’s stromal bed with no sutures,” Dr. Busin said. “The ‘mushroom head’ is then placed on the top and fixed with a running 10-0 nylon suture, as we do in conventional lamellar keratoplasty,” Dr. Busin said.

Postoperatively, antibiotic and corticosteroid drops are administered every 2 hours for 2 weeks and than tapered off over a period of 3 months. Sutures are removed 3 to 4 months after surgery.

Posted by aman at 01:28 AM | Comments (0)

Intraocular Pressure Measurement After Hyperopic and MyopicLASIK

OSN Refractive surgery
Intraocular pressure was measured by Goldmann applanation tonometry pre- and postoperatively in 48 hyperopic eyes (26 patients) and 56 myopic eyes (28 patients).
Result
The mean preoperative spherical equivalent refraction was +3.97 ± 2.48 diopters (D) in the hyperopic group and –6.73 ± 4.79 D in the myopic group. Attempted correction was equivalent to preoperative refraction in each group. Mean preoperative IOP was 14.22 ± 2.56 mmHg and 13.70 ± 2.09 mmHg in the hyperopic and myopic groups, respectively. Following LASIK, the mean IOP was 11.85 ± 2.52 mmHg and 11.38 ± 3.08 mmHg in the hyperopic and myopic groups, respectively.
Conclusion
The IOP measurement was significantly reduced (P < .001) by 2.37 ± 2.25 mmHg and 2.32 ± 2.89 mmHg following hyperopic and myopic LASIK, respectively. [J Refract Surg. 2005;21:408-410.]

Posted by aman at 01:18 AM | Comments (0)

Keratometry for Intraocular Lens Power Calculation Using Orbscan II in Eyes With Laser in situ Keratomileusis

OSN Refractive surgery
To compare the results of corneal keratometry after laser in situ keratomileusis (LASIK) obtained by the Gaussian optics formula and the clinical history method.
Method
Sixty-one consecutive patients (121 eyes) who had undergone LASIK were recruited in this retrospective case-controlled study. The K-value obtained from the Gaussian optics formula (CalK) based on postoperative corneal topography by Orbscan II (Bausch & Lomb, Rochester, NY) and ultrasound pachymetry was compared with that obtained from the clinical history method (estK). Keratometry measured by these two methods was compared using the paired sample t test and Pearson correlation coefficient.
Result
A high correlation was noted between K-value obtained by the clinical history method and the Gaussian optics formula (R = 0.97, P < .001). The mean difference between the two methods is 0.13 diopters (P = .06).
Conclusion
K reading derived from the Gaussian optics formula correlated closely to that obtained from the clinical history method and would be especially useful in patients with no preoperative LASIK treatment data. [J Refract Surg. 2005;21:365-368.]

Posted by aman at 01:08 AM | Comments (0)

The Safety and Efficacy of Photorefractive Keratectomy After Laser in situ Keratomileusis

OSN Refractive surgery
Fifteen eyes of 14 patients who had initially received LASIK for the treatment of myopia and compound myopic astigmatism were evaluated. Variables included existence of and/or type of flap complication associated with the original LASIK procedure, refractions before and after (3 and 6 months) PRK, uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), and the development of complications after PRK such as haze, scarring, double vision, or ghosting.
Result
All 15 eyes were available for analysis at 6 months. Eleven eyes had experienced flap complications during the initial LASIK procedure and 4 eyes had experienced complications in the LASIK postoperative period. Characteristics prior to performing PRK included 11 myopic and 4 hyperopic eyes. By 6 months after PRK treatment, 87% of eyes had UCVA > 20/40, 53% had > 20/25, and 40% had > 20/20. All eyes had BSCVA of > 20/30, with 73% being > 20/20. No eye had lost 2 lines of BSCVA and only 1 eye lost 1 line of BSCVA. Sixty percent of eyes were within 1.0 diopters (D) of emmetropia, and 40% were within 0.5 D of emmetropia. A trend towards undercorrection and surgical induction of astigmatism as confirmed by vector analysis was noted. No eye developed significant haze or scarring.
Conclusion
Photorefractive keratectomy may be a safe procedure to perform in corneas previously treated with LASIK surgery. Results show good reduction of refractive error and improvement of UCVA and BSCVA. A significant undercorrection of astigmatism was attributed to surgically induced astigmatism. Further studies are necessary to determine the long-term safety and stability of outcomes. [J Refract Surg. 2005;21:353-358.]

Posted by aman at 12:44 AM | Comments (0)

Descemet’s Stripping With Endothelial Keratoplasty in 50 Eyes: ARefractive Neutral Corneal Transplant

OSN supersite Refractive surgery
Visual and refractive outcomes of the first 50 consecutive cases of DSEK performed by a single surgeon between December 2003 and July 2004 were analyzed retrospectively. The DSEK technique consisted of stripping Descemet’s membrane and endothelium from a recipient cornea and transplanting the posterior stroma and endothelium of a donor cornea through a 5-mm incision.
Results
are reported for 50 eyes in 47 patients (30 women and 17 men). Mean patient age at surgery was 70 ± 12 years (range: 34 to 89 years). Five eyes were treated for corneal edema or bullous keratopathy and 45 for Fuchs’ endothelial dystrophy. Seven eyes were phakic and 43 were pseudophakic. Six months after surgery, mean manifest cylinder was 1.5 ± 0.94 diopters (D), unchanged from preoperative cylinder of 1.5 ± 1.0 D. Mean manifest spherical equivalent refraction was 0.15 ± 1.5 D at 6-month follow-up compared with –0.36 ± 1.4 D preoperatively (P = .10) At 3- and 6-month follow-up, significant improvement was noted in mean best spectacle-corrected visual acuity compared with the preoperative mean of 20/100 (P=.007). At 6-month follow-up, 31 (62%) eyes refracted to > 20/40 and 38 (76%) eyes saw > 20/50.
Conclusion
Compared to standard penetrating keratoplasty, DSEK causes minimal refractive change and provides rapid visual recovery for patients with endothelial dysfunction. This technique maintains the structural integrity of the cornea by preserving the recipient’s epithelium, Bowman’s layer, and entire stromal thickness. [J Refract Surg. 2005;21:339-345.]

Posted by aman at 12:35 AM | Comments (0)

July 24, 2005

Outcomes of phacoemulsification and in-the-bag intraocular lens implantation in Fuchs' heterochromic iridocyclitis

JCRS Pages 997-1001 (May 2005)

Mohammad-Ali Javadi, MD, Mohammad-Reza Jafarinasab

To evaluate the visual outcomes and complications of PhacoIOL in patients with Fuchs heterochromic iridocyclitis (FHIC).

In this noncomparative interventional case series, existing data for 41 eyes of 40 consecutive patients clinically diagnosed with FHIC and cataract were studied retrospectively. Scleral tunnel PE and in-the-bag IOL implantation were performed in all cases. Preoperative and postoperative visual acuities and intraoperative and postoperative complications were evaluated.

Results
Twenty-four male and 16 female patients aged 12 years to 70 were operated on and followed for 17.8 months. Preop BCVA was less than 20/40 in all patients, which improved to 20/40 or better after surgery. Twenty-two eyes (53.6%) achieved BCVA of 20/20. The major cause of postop VA less than 20/20 was vitreous haze. There were no major intraoperative complications. Postop mild anterior chamber fibrin reaction occurred in 4 patients (9.7%), IOL deposits occurred in 11 eyes (26.8%), and decentration was observed in 1 eye. During follow-up, 6 eyes (14.6%) developed posterior capsule opacification requiring a neodymium:YAG (Nd:YAG) laser capsulotomy. There was 1 case of clinical cystoid macular edema that resolved with medication. There were no cases of posterior synechias, postoperative glaucoma, or retinal detachment.

Conclusion
Phacoemulsification with PC IOL implantation is a safe procedure with good visual outcomes in patients with FHIC and cataract.

Posted by alireza habibollahi at 03:52 PM | Comments (0)

Pre-op use of warfarin and aspirin in cataract surgery by Canadian Society of Cataract and Refractive Surgery members(CSCRS)

JCRS Pages 991-996 (May 2005)
Canada,Members of the CSCRS were faxed a questionnaire that examined their perioperative management of patients being treated with warfarin and aspirin.

Results
Of the 110 eligible participants, 82 returned a completed questionnaire, representing a response rate of 74.5%. Warfarin or aspirin was routinely stopped prior to cataract surgery by 25.6% of the respondents. The majority of surgeons who discontinued these medications reported doing so 3 to 7 days prior to surgery and resumed their use 1 to 2 days postoperatively. Topical anesthesia and clear corneal incisions were preferred by the higher volume surgeons. These surgeons were also less likely to discontinue either warfarin or aspirin preoperatively.

Conclusions
The majority of the Canadian Society of Cataract and Refractive Surgery members do not stop either warfarin or aspirin for cataract surgery during the perioperative period.

Posted by alireza habibollahi at 03:46 PM | Comments (0)

LASIK for refractive error after cataract surgery

JCRS Pages 979-986 (May 2005)
To evaluate the safety and efficacy of LASIK to correct refractive error following cataract surgery.
The mean age was 63.5 years . The mean F/U 8.4 months,and mean interval between cataract surgery and LASIK was 12 months .
The mean pre-op SEQ for myopic eyes was −3.08 D and for hyperopic eyes was +1.82D. The mean improvement following LASIK surgery was greater for myopic than hyperopic eyes (myopic, 2.54 D versus hyperopic, 1.73 D). The percentage of patients within ±0.5 D of intended refraction post-LASIK surgery was 83.3% for myopic eyes and 90.9% for hyperopic eyes and all eyes were within ±1.0 D of intended (P<.001). The percentage of eyes with uncorrected visual acuity of 20/40 or better in the myopic group improved from none preoperatively to 91.7% postoperatively (P<.001) and in the hyperopic group improved from 27.3% preoperatively to 90.9% postoperatively (P=.008). No eyes lost 2 or more lines of best corrected visual acuity.

Conclusion
LASIK appears to be effective in correcting refractive error following cataract surgery. Longer-term studies are required to determine refractive stability.

Posted by alireza habibollahi at 03:36 PM | Comments (0)

Short-term changes in the morphology of posterior capsule opacification

JCRS Pages 962-968 (May 2005)
To observe and document PCO over 4 weeks.

Fifteen eyes of pseudophakic patients with PCO of varying degrees were included in this prospective study. Digital retroillumination images were taken in a standardized fashion at 3 time points: 1 baseline image, a second image after 2 weeks, and a third image after 4 weeks. Thus, a 3-image series could be created for each eye. Additionally, sections of the posterior capsule with interesting structures were photographed with higher magnification and compared in supplementary image series. Morphologic changes in the PCO structure (eg, number and size of Elschnig pearls, total PCO area) were analyzed in the image series.

Conclusions
Development of (regeneratory) PCO is a very dynamic process that includes not only growth of preexisting structures and occurrence of new Elschnig pearls, but also reorganization and even disappearance of pearls within a short time period (2–4 weeks). The latter in particular is not well known but could be observed in the majority of cases in this study.The total PCO area did not change significantly during the 4-week period.

Posted by alireza habibollahi at 03:27 PM | Comments (0)

Intraocular contact lens tamponade to facilitate penetrating keratoplasty in perforated corneas

JCRS Pages 876-878 (May 2005)
PK in the presence of a perforated cornea is a relatively common and difficult surgical problem. In the worst scenario, there may be extrusion of ocular contents during trephination. Two cases of perforated corneas are presented in which a new technique was used to close the perforation and normalize intraocular pressure. This involves inserting a soft contact lens through a paracentesis into the anterior chamber. An ophthalmic viscosurgical device is then injected behind the contact lens, opening it, and allowing it to tamponade the perforation. This stabilizes the anterior chamber and allows a stable operating environment. This has not been described previously.

Posted by alireza habibollahi at 03:23 PM | Comments (0)

Spontaneous fracture of an implanted posterior chamber intraocular lens

EJO July 2005
Spontaneous fracture of an intraocular lens (IOL) haptic is a rare complication of cataractsurgery. The authors report a case of spontaneous fracture of an implanted posterior chamber IOL.
CASE. Five years ago, a 12-year-old patient underwent linear lens extraction, posterior capsulotomy, and anterior vitrectomy due to traumatic cataract and received a polymethyl methacrylate (PMMA) biconvex posterior chamber IOL implanted in ciliary sulcus. Five years later, IOL optic was found in anterior chamber with its haptics broken from the optic-haptic junction.
DISCUSSION. The broken haptic was examined with scanning electron microscopy. The fracture site of the haptic was on the optic-haptic junction. The fractured surface had a regular appearance.
CONCLUSIONS. To our knowledge, this is the fourth report of spontaneous fracture of an implanted

Posted by aman at 02:41 AM | Comments (0)

Implantation of iris devices in congenital and traumatic aniridias: Surgery solutions and complications

EJO July 2005
Eight patients were included in this retrospective noncomparative case series. Nine eyes had an artificial iris implantation for traumatic or congenital aniridia. Three eyes received a black diaphragm intraocular lens (IOL) in capsular bag after phacoemulsification. An aniridia prosthesis, sulcus sutured, in front of a previous IOL was implanted in two eyes. A black diaphragm IOL, sulcus sutured, in two eyes; two iris diaphragm rings, in front of the previous IOL, in one eye; and a sector iris prosthesis in front of an IOL in the last eye were implanted. Mean follow-up was 22.5 months (range 16 to 44 months).
Results. All patients had improved visual acuity (VA) and visual comfort after surgery. The glare disability was subjectively better in all cases. Two patients developed new ocular hypertension after surgery; one of them was controlled by medical treatment and the other needed cyclodiode. Two of the patients with glaucoma preoperatively also needed cyclodiode procedure and one of them an Ahmed valve.
Conclusions. Several kinds of artificial iris implants are available. In all our patients with aniridia, iris artificial prostheses improved VA and diminished visual discomfort. Glaucoma is the most important complication after artificial iris implant. It is possible to implant the iris prosthesis in the capsular bag, but this requires a large capsulorrhexis and presents a surgical challenge.

Posted by aman at 02:04 AM | Comments (0)

Corneal epithelial healing after photorefractive keratectomy:

Jcrs May 2005
Investigators considered how three different corneal ablation patterns affected the speed of epithelial migration after photorefractive keratectomy (PRK). The study included 15 patients (30 eyes) with mild to moderate myopia and simple compound myopic astigmatism. For the 10 eyes in the low spherical migration group, the mean speed of radial migration was the highest of the three groups at 0.087 mm/h. For the 10 eyes in the high spherical ablation group, the mean speed was 0.078 mm/h and for the remaining 10 eyes in the cross-cylinder ablation group the speed was 0.055 mm/h. Investigators determined that the ablation pattern influenced epithelial migration along the photoablated corneal surface. Local variations in the curvature of the stromal surface strongly affected the epithelial sliding. From the data, they determined that cases with faster epithelial wound healing were more likely to have optimal visual performance.

Posted by aman at 01:56 AM | Comments (0)

July 23, 2005

Preferred treatment depends on severity of AMD

OSN 2005
The best treatment for age-related macular degeneration depends on the severity of the disease. Visudyne photodynamic therapy, PDT with injection of intravitreal triamcinolone, and Macugen (pegaptanib sodium injection, Eyetech/Pfizer) are all treatment options in patients with larger lesions and poorer visual acuities. When the patient’s visual acuity is still relatively good, treatment choices should be based on the individual physician’s experience and the patient’s preference. PDT was the preferred treatment for many cases, either with or without intravitreal triamcinolone. For patients with relatively good visual acuity (20/40 or better) and small lesions, most experts recommended following the patient rather than beginning any treatment. In cases in which lesions seemed to be progressing and visual acuity decreasing (to 20/80 or worse), the experts almost unanimously recommended Macugen as the preferred treatment. Once a patient has progressed to very poor vision (20/800 or worse) and large lesions, the experts debated whether any treatment is beneficial. There’s no guidance on when to stop treatment altogether, or how to relate that to patient comfort. Where’s there’s fluid, there’s hope for improved vision. If the lesion continues to progress, vision continues to deteriorate and the patient won’t notice further decline in vision, you just have to stop.

Posted by kjalali at 07:48 PM | Comments (0)

Intravitreal triamcinolone safe in retrospective study of cataract, AMD

OSN 2005
The purpose of this retrospective study was to determine if intravitreal triamcinolone acetonide (TA) injection is safe when combined with cataract surgery for eyes with AMD in the effort to possibly reduce the risk of AMD progression.All of the operated eyes showed evidence of AMD, but none were exudative at the time. The cataract surgery was standard and involved a clear corneal incision, phacoemulsification and aspiration of the cataract, and implantation of a foldable posterior chamber IOL. At the conclusion of the routine cataract surgery, 4 mg/0.1 ml of Kenacort A-40 (triamcinolone acetonide, Bristol-Myers Squibb) was injected into the vitreous cavity through the superonasal or superotemporal pars plana. Paracentesis of the anterior chamber was performed to control IOP.Although this case series was small and uncontrolled, intravitreal TA injection when combined with cataract surgery was safe and well tolerated.The two eyes in this study (10%) that developed CNV membrane 3 to 6 months after the combined cataract surgery and intravitreal TA had reasonable final visual outcome (6/30 and 6/48). It may also be beneficial in other conditions such as in preventing postoperative cystoid macular edema in high-risk eyes such as those with uveitis and diabetic retinopathy undergoing cataract surgery. Large controlled studies are required to evaluate the risk of AMD progression and CNV development in eyes undergoing cataract surgery and the benefit of intravitreal TA in reducing that risk.

Posted by kjalali at 07:39 PM | Comments (0)

Genaera reports additional phase II results for wet AMD treatment, Envizon

Genaera Corporation
The company this week announced results for patients receiving a 20 mg dose of this systemically delivered anti-angiogenic drug. Of these patients, 17 percent showed three lines or greater vision improvement, and 83 percent had either stable or improved vision at month four. Also, all subjects diagnosed with wet AMD in the fellow eye had stable or improved vision though month four. Data on subjects who received the 40 mg dose was released in February 2005.

Posted by kjalali at 07:20 PM | Comments (0)

Technique allows IOL insertion through sub-2-mm incision after coaxial phaco

OSN 6/3/2005

....technique for cataract surgery that allows IOL insertion through an incision of less than 2 mm following coaxial phacoemulsification will lead ophthalmologists to say "Sayonara, Bimanual," according to Takayuki Akahoshi, MD......Loading the C-cartridge, Dr. Akahoshi places both haptics on the optic and places the lens in the cartridge at a downward angle. After affixing the cartridge to the injector handpiece, he stabilizes the eye with the nuclear sustainer, which also serves to provide a counterforce to the injection. The cartridge will not fit through the ultrasmall incision, so Dr. Akahoshi places it just at the edge of the incision and pushes the plunger to inject the lens into the eye through the unenlarged sub-2-mm incision. '''''A key to the technique, Dr. Akahoshi said, is the elbow joint between the optic and the haptic on the AcrySof lens. When he pushes the lens through the incision, “the elbow can easily open the incision and open into the anterior chamber,” he said.

Posted by mehdi khanlari at 09:30 AM | Comments (0)

Eurotimes July 2005

ADVANCED OPTICS ASPHERIC INTRAOCULAR LENSES Bausch & Lomb has announced the launch of the Advanced Optics Aspheric Intraocular Lenses - designed for improved visual quality.These new lenses are the first aberration-free IOLs with uniform lens power from centre to edge. Even in circumstances when the centration and orientation of the lens is compromised, the lens delivers consistently excellent visual benefits.The Bausch & Lomb Advanced Optics lens is available in both acrylic (Akreos Adapt- AO) and silicone (SofPort LI61-AO) versions to accommodate surgeon’s preference of lens material.The LI60-AO is launched with the new, SofPort Easy-Load Lens Delivery System. By\ eliminating the critical steps of lens handling and loading, this automated injection system (EZ-28) offers quick, predictable, reliable and controlled lens insertion through a sub-3.0-mm incision.The Adapt-AO is launched with the new Akreos Single Use Insertion Device (AI-28), also designed to offer quick and controlled lens insertion through a sub-3.0-mm incision. Website: www.bausch.com

Posted by mehdi khanlari at 09:27 AM | Comments (0)

eurotimes July 2005
NEW ROYALE II:AE-9045SP ASICO introduces a new spring injector, which allows implanting the AcrySof through a 2.0 mm incision. The injector was developed by Dr. Akahoshi. It has a spring plunger mechanism, which enables a more efficient and precise IOL implantation

Posted by mehdi khanlari at 09:12 AM | Comments (0)

New glaucoma monitoring device provides

Eurotimes July 2005

A NEW device called the TonoPach (RetinaPharma) provides simultaneous measurements of intraocular pressure and central corneal thickness (CCT).The combined measurements should lead to more accurate glaucoma diagnosis, the instrument’s developers say. The device contains a tonometer to measure IOP and an ultrasonic pachymeter to measure CCT.The TonoPach is a portable, battery operated, handheld instrument that can be used with the patient in any position. The device received FDA approval in December 2004

Posted by mehdi khanlari at 08:49 AM | Comments (0)

Formula may help with post-LASIK IOP management

Eurotimes July 2005

THE effect of LASIK on intraocular pressure (IOP) can be predicted with a reasonable degree of accuracy using data readily available to optometrists and ophthalmologists, according to a British study presented here during the 9th Winter Refractive Surgery meeting of the ESCRS.....we found that a relatively simple formula can be produced which is reasonably accurate for predicting postoperative IOP from the preoperative IOP and other parameters. In essence the formula that was derived is that preoperative IOP is related to postoperative IOP, mean curvature change and postoperative corneal thickness minus a factor of 7.3,”

Posted by mehdi khanlari at 08:42 AM | Comments (0)

July 22, 2005

Conjunctival Pyogenic Granulomas after Strabismus Surgery

Ophthalmology,July,2005

Conjunctival pyogenic granulomas are a potential complication of strabismus surgery. Treatment with topical steroids is an effective initial treatment for most patients with pyogenic granulomas. Surgical excision is effective in patients who do not improve with topical medication. Patients with multiple surgeries do not seem to be at increased risk for pyogenic granulomas, and the occurrence of a pyogenic granuloma does not seem to increase the risk of developing pyogenic granulomas in future surgeries.

Posted by afarahi at 11:18 PM | Comments (0)

Lateral rectus muscle disinsertion and reattachment to the lateral orbital wall

BJO,August,2005
Surgical correction of ocular alignment in patients with third cranial nerve paralysis is challenging, as the unopposed lateral rectus muscle often pulls the eye back to exotropia following surgery. The authors present a simple surgical approach to overcome this difficulty. This approach is also applicable to removal of unwanted overactivity of the lateral rectus in Duane syndrome.
In five patients the lateral rectus muscle was removed from its scleral insertion and reattached to the orbital wall. Additional surgery to bring the eye to the midline included medial rectus resection, medial transposition of the vertical recti, and passive suturing of the eye to the medial orbit wall. All patients achieved satisfactory ocular alignment following surgery. Ocular ductions were limited. These results were stable for 1.5–4 years of follow up. No major complications occurred.

Posted by afarahi at 08:50 PM | Comments (0)

Perioperative use of warfarin and aspirin in cataract surgery by Canadian Society of Cataract and Refractive Surgery members: Survey

JCRS May 2005
To survey the members of the Canadian Society of Cataract and Refractive Surgery (CSCRS) and identify their practices regarding the perioperative use of warfarin and acetylsalicylic acid (aspirin) in cataract surgery.
Of the 110 eligible participants, 82 returned a completed questionnaire, representing a response rate of 74.5%. Warfarin or aspirin was routinely stopped prior to cataract surgery by 25.6% of the respondents. The majority of surgeons who discontinued these medications reported doing so 3 to 7 days prior to surgery and resumed their use 1 to 2 days postoperatively. Topical anesthesia and clear corneal incisions were preferred by the higher volume surgeons. These surgeons were also less likely to discontinue either warfarin or aspirin preoperatively.
Conclusions
The majority of the Canadian Society of Cataract and Refractive Surgery members do not stop either warfarin or aspirin for cataract surgery during the perioperative period.

Posted by aman at 03:24 PM | Comments (0)

Cytoskeletal agents: future option for reducing IOP?

Ophthalmology times Feb 2005
—Cytoskeletal agents, which increase outflow facility in the trabecular meshwork, are one of the drug classes that could expand the pharmaceutical options available to reduce IOP, said Carl B. Camras, MD, professor, chairman, and director of the glaucoma service, department of ophthalmology, University of Nebraska Medical Center, Omaha.
Cytoskeletal agents increase outflow facility by disrupting the microtubules or actin microfilament cytoskeleton in the trabecular meshwork.
They can also rupture the inner wall of Schlemm's canal or inhibit microtubule assembly. They alter cell shape and cell-cell or cell-matrix interactions. They sequester monomeric G-actin and cause disassembly of actin filaments. In addition, cytoskeletal agents also reduce trabecular meshwork cell contractility, prevent elongation of actin filaments, and distend the trabecular meshwork.
Investigators have been looking into various cytoskeletal agents since the 1970s. These agents include cytochalasins, ethacrynic acid (a phenoxyacetic acid derivative), ticrynafen (nonsulfhydryl-reactive compound similar to ethacrynic acid), marine macrolides, protein kinase C activators (phorbol myristate acetate), and protein kinase inhibitors.
There is a downside. Cytoskeletal agents may adversely affect the anterior segment tissues, since the microtubules in the cytoskeleton occur not only in the meshwork and outflow channels but also in the cornea, other parts of the eye, and most other tissues, Dr. Camras said.
One early study showed a significant effect on central corneal thickness after application of these agents in monkeys. However, a more recent study demonstrated that when lower concentrations were used in larger volumes, the effect on corneal thickness was more limited.
However, Dr. Camras suggested that the next FDA-approved glaucoma drugs are likely to be combination products or other modified drugs within the existing classes.

Posted by aman at 03:10 PM | Comments (0)

Re-evaluate target pressure after disc hemorrhage

Ophthalmology times Mar 2005
—Optic disc hemorrhage, a rare event in non-glaucomatous eyes, is a strong predictor of glaucoma as well as glaucoma progression. Clinicians might consider re-evaluating the patient's target IOP after this finding, said Jost B. Jonas, MD, at the American Academy of Ophthalmology's glaucoma subspecialty day meeting.
Disc hemorrhages have been detected in about 4% to 7% of glaucomatous eyes but are rarely seen in eyes without glaucoma.
The stage of glaucoma influences the location and frequency of optic disc hemorrhages. In the early stage of the disease, disc hemorrhages are found in the inferotemporal disc region. As the disease progresses to a medium-advanced stage, bleeding can also occur in the temporal superior and temporal horizontal disc regions. "Disc hemorrhages are usually not found in disc regions or eyes without detectable neuroretinal rim," he said.
Risk factors for bleeding Dr. Jonas and colleagues reported in 2002 that small neuroretinal rim size and a large beta zone of parapapillary atrophy are risk factors for optic disc hemorrhages. Factors that did not differ between the hemorrhagic group and non-hemorrhagic group were optic disc size and shape, optic disc depth, alpha zone of parapapillary atrophy, and retinal vessel diameter, Dr. Jonas said.
Numerous studies have indicated that optic disc hemorrhages put patients at risk for glaucoma or glaucoma progression. In the Ocular Hypertension Treatment Study (OHTS), Budenz and colleagues studied optic disc hemorrhages as a predictor of the development of glaucoma. They found that 20% of the 152 eyes with detected disc hemorrhages developed glaucoma during follow-up. In these eyes, glaucoma was detected at a median of 16.3 months, Dr. Jonas said.
"The OHTS offers convincing evidence that the target pressure should be reconsidered," he said. "It is yet open whether the target pressure should be re-adjusted."

Posted by aman at 03:00 PM | Comments (0)

Positive results seen at 12 months for laser persbyopia

Ophthalmology times Apr 2005
—Laser presbyopia reversal (LAPR) is showing significant promise and patient satisfaction based on 12-month follow-up results from a U.S. phase II clinical trial, said Sandra C. Belmont, MD.

The procedure involves the use of an infrared erbium:YAG laser (OptiVision, SurgiLight) fitted with a conical tip fiber to create eight radial incisions in the sclera via tissue ablation. It is designed to improve accommodation by expanding the scleral tissue in order to enhance the efficiency of the ciliary muscle and zonules.
The phase II study was conducted at two centers and enrolled 60 eyes of 30 patients with a mean age of 53 years (range 50 to 58). The eligibility criteria required patients to have distance uncorrected visual acuity (UCVA) of 20/25 or better in each eye, accommodation 2.5 D, stable manifest refraction between -0.5 and +0.75 D with 0.5 D difference between the manifest and cycloplegic SE values, normal IOP, ≤0.75 D astigmatism, and no prior ophthalmic surgery. First-eye and second-eye surgery were performed 1 day apart.
Patients were able to read immediately after surgery, and at 12 months, the group demonstrated a statistically significant increase in near uncorrected visual acuity (UCVA), with 90% achieving J3 or better. In addition, 100% of eyes had >1 D increased amplitude of accommodation with a mean increase after 12 months of about 2.4 D when measured by push-up and blur and a maximum increase of 3.25 D. One patient with a poor 12-month near vision outcome had resumed spectacle wear. Safety was favorable with no changes in IOP, axial length, or corneal topography, and patients have been very happy with the results.
The laser used for the surgery has an output energy of 20 mJ, operates at a frequency of 20 Hz, and has a spot size of 400 µm. LAPR is performed under topical anesthesia using 2% lidocaine gel applied preoperatively and topical 1% proparacaine delivered via a pledget to the sclera for 3 to 5 minutes during the procedure.
The eye is marked at 6 and 12 o'clock with the patient in the sitting position, and four fornix-based triangular peritomies are made at 1:30, 4:30, 7:30 and 10:30. Wet field cautery is applied as needed.
The eight radially oriented ablations are made in the scleral tissue 0.5 mm posterior to the limbus. They measure 4.5 mm in length and are placed two per quadrant and spaced 2.5 mm apart. The depth of the ablation is about 80% of scleral thickness, and the appearance of the dark blue hue of the choroid marks the treatment endpoint.
The peritomy sites are closed with a bipolar forceps and topical treatment with a nonsteroidal anti-inflammatory agent and antibiotic is administered.

Posted by aman at 02:17 PM | Comments (0)

Clinical manifestation and pathologic finding of unilateral acute hydrops after bilateral laser in situ keratomileusis

Journal of Cataract & Refractive Surgery Volume 31, Issue 6 , June 2005, Pages 1244-1248

We present a case of unilateral acute hydrops that developed in 25-year-old man 6 years after bilateral laser in situ keratomileusis (LASIK) for the correction of 2.75 diopters (D) of myopia. Preoperative corneal thickness using ultrasound pachymetry were 556 μm in the right eye and 554 μm in the left eye. Preoperative corneal topography of both eyes showed an asymmetric bow-tie pattern with inferior steepening. Forty-seven months after LASIK, the left eye developed astigmatism and enhancement excimer ablation was performed. Sixteen months after enhancement, a definite sign of keratectasia was detected in the left eye. Twenty-six months after enhancement, acute hydrops occurred in the left eye. The interface of the LASIK wound was separated and filled with aqueous humor. Penetrating keratoplasty was performed to avoid perforation. The keratocytes at the edge between the peripheral flap and remaining stroma showed mixoid degeneration and edematous change suggesting dying cells.

Posted by mmiraftab at 12:20 PM | Comments (0)

Unexpected outcomes associated with laser in situ keratomileusis: Ptosis, anisocoria, and “curing” of exotropia

Journal of Cataract & Refractive Surgery Volume 31, Issue 6 , June 2005, Pages 1238-1241


Laser in situ keratomileusis (LASIK) is a common and popular procedure that is generally associated with excellent results and few complications. We present 3 cases of unusual LASIK-related complications. In the first case, the patient developed anisocoria after otherwise unremarkable surgery. In the second case, the patient developed mild eyelid ptosis. In the third case, the patient's exotropia resolved after mild refractive overcorrection. In each case, the visual outcome was excellent and no further intervention was necessary.

Posted by mmiraftab at 12:17 PM | Comments (0)

Decrease in complications during cataract surgery with the use of a silicone-tipped irrigation/aspiration instrument

Journal of Cataract & Refractive Surgery Volume 31, Issue 6 , June 2005, Pages 1194-1197

A retrospective chart review of all patients who had cataract extraction by phacoemulsification by third-year ophthalmology residents between September 2000 and February 2004 was conducted. A silicone-tipped I/A instrument was used to remove cortex for all surgeries beginning in September 2002, whereas a metal I/A tip was used previously.
Results
Of the 1072 cases performed with a metal I/A tip, there were 13 cases of vitreous loss during cortex removal (rate 1.2%) and 26% of all vitreous loss during that time occurred during cortex removal. Of the 805 cases performed with a silicone I/A tip, there was a single case (0.1%) of vitreous loss during cortex removal (P = .004); only 4% of all vitreous loss during that time occurred during cortex removal (P = .011).
Conclusion
The overall incidence of vitreous loss during cortex removal and the ratio of vitreous loss during cortex removal to all cases of vitreous loss were significantly decreased using the silicone-tipped I/A instrument.

Posted by mmiraftab at 12:02 PM | Comments (0)

Paired opposite clear corneal incisions to correct preexisting astigmatism in cataract patients

Journal of Cataract & Refractive Surgery Volume 31, Issue 6 , June 2005, Pages 1167-1170

Fifteen eyes of 14 cataract patients with a mean age of 78.4 years ± 6.38 (SD) (range 69 to 90 years) were recruited for the study. Inclusion criterion was topographic astigmatism of more than 2 diopters (D) in the cataractous eye. Preoperative refraction, autokeratometry, and topography were performed. The steep axis was marked before sub-Tenon's anesthesia was given. Paired 3-step self-sealing opposite clear corneal incisions were made 1 mm anterior to limbus on the steep axis with a 3.2 mm keratome. One incision was used for standard phacoemulsification, and the other was left unused for astigmatic correction. All the patients had day-case surgery. The first follow-up was at 1 month. Postoperative topography, keratometry, and refraction were performed on all patients.
Results
Mean preoperative and postoperative topographic corneal astigmatism were 3.26 ± 1.03 D (range 2.30 to 5.80 D) and 2.02 ± 1.04 D (range 0.20 to 4.00 D), respectively. Mean astigmatic correction was 1.23 ± 0.49 D (range 0.30 to 2.20 D). Mean surgically induced astigmatism by vector analysis was 2.10 ± 0.79 D (range 0.80 to 3.36 D). There were no incision-related complications.
Conclusion
Paired opposite clear corneal incisions on the steep axis is a useful way to correct astigmatism in cataract patients, requiring no extra skill or instrumentation.

Posted by mmiraftab at 11:55 AM | Comments (0)

Excimer laser photorefractive keratectomy for hyperopia: 7.5-year follow-up

Journal of Cataract & Refractive Surgery Volume 31, Issue 6 , June 2005, Pages 1104-1113

At 7.5 years, the refractive correction remained stable with a mean difference in SEQ between 1 year and 7.5 years of +0.28 D. The mean manifest SEQ was +0.83 D (range +5.00 to −3.00 D). Sixty-seven percent of eyes having corrections of +1.50 D and +3.00 D were within ±1.00 D of the predicted correction. Predictability was poorer with +4.50 D and +6.00 D corrections, with 40% of eyes within ±1.00 D of that expected. An improvement in uncorrected near acuity was achieved in 35 eyes (87.5%), and 35 eyes (87.5%) showed an improvement in uncorrected distance acuity from preoperative levels. Best spectacle-corrected visual acuity (BSCVA) was unchanged or improved from preoperative values in 25 eyes (62.5%). Three eyes (8%) lost 2 lines of Snellen BSCVA, which in 2 cases was attributable to cataract formation. A peripheral ring of haze, 6.5 mm in diameter, appeared in most eyes. Its intensity was greatest at 6 months and then diminished with time. In 10 eyes (25%), remnants of the haze ring were evident at 7.5 years and subepithelial iron rings, 6.5 mm in diameter were evident in 26 eyes (70%). No patient complained of night-vision problems and no eye developed ectasia.
Conclusions
In H-PRK, refractive stability achieved at 1 year was maintained up to 7.5 years with no evidence of hyperopic shift, diurnal fluctuation, or late regression. Peripheral corneal haze decreased with time but was still evident in a number of eyes at the last follow-up visit.

Posted by mmiraftab at 11:38 AM | Comments (0)

Effect of tranexamic acid on early postvitrectomy diabetic haemorrhage; a randomised clinical trial

British Journal of Ophthalmology 2005;89:1041-1044
A R Ramezani, H Ahmadieh, A K Ghaseminejad, S Yazdani1 and B Golestan

Methods: In a clinical trial, 62 diabetic patients scheduled for vitrectomy were randomly assigned to two groups. The treatment group (32 eyes) received two doses of tranexamic acid (10 mg/kg) shortly before and after the operation intravenously, continued orally for 4 days (20 mg/kg/8 hours). The control group (30 eyes) received no medication. Both media clarity and visual acuity were compared during 4 weeks.
Results: Four weeks after surgery visual acuity was low (1 metre counting fingers) in 21.4%, moderate (>1 metre counting fingers but<20/200) in 14.3%, and good (20/200) in 64.3% of the treated group. Corresponding figures in the control group were 26.1%, 26.1%, and 47.8%, respectively. These differences were of no statistical significance. The ratio of mild to severe vitreous haemorrhage during the first 4 days and after 4 weeks was 79% to 21% and 82% to 18% in the treatment group and 76.7% to 23.3% and 78.3% to 21.7% in the control group respectively, which showed no statistically significant difference.
Conclusion: Tranexamic acid, with the method of administration in this study, had no effect on reducing early postvitrectomy haemorrhage in diabetic patients.

Posted by mmiraftab at 11:31 AM | Comments (0)

Clinical evaluation of frequency doubling technology perimetry using the Humphrey Matrix 24-2 threshold strategy

British Journal of Ophthalmology 2005;89:1031-1035

Methods: A random sample of individuals referred consecutively to the HES for suspected glaucoma were examined with 24-2 threshold FDT in addition to routine clinical tests. The discriminatory power of FDT and standard automated perimetry (SAP) were assessed using glaucomatous optic nerve head appearance as the reference gold standard.
Results: 48 of 62 eligible referred individuals were recruited. Glaucoma prevalence was 31%. Median test duration per eye was 5 minutes 16 seconds for FDT and 5