Journal of Ophthalmic and Vision Research
Volume:5 Issue: 4, Oct-Dec 2010

To compare spherical aberration and contrast sensitivity function following implantation of four different foldable posterior chamber intraocular lenses (IOLs), namely Sensar, Akreos AO, Tecnis, and AcrySof IQ. In this randomized clinical trial, 68 eyes of 68 patients with senile cataracts underwent phacoemulsification and IOL implantation with Sensar (n=17), Akreos AO (n=17), Tecnis (n=17), or AcrySof IQ (n=17). Uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA), spherical aberration and contrast sensitivity function (CSF) were compared among the study groups, 3 months after surgery. There was no significant difference between the study groups in terms of age (P = 0.21). Mean postoperative BSCVA with Sensar, Akreos AO, Tecnis, and AcrySof IQ was 0.15±0.10, 0.12±0.9, 0.08±0.08, and 0.08±0.07 logMAR, respectively (P=0.08). Spherical aberration measured over a 4 mm pupil was significantly higher with Sensar and Akreos AO than the two other IOLs. The difference between Tecnis and AcrySof IQ was significantly in favor of the former IOL. Over a 6 mm pupil, spherical aberrations were comparable with Sensar and Akreos AO, furthermore spherical aberration was also comparable among eyes implanted with Akreos AO, AcrySof IQ, and Tecnis. Sensar yielded significantly inferior results as compared to Acrysof IQ and Tecnis. CSF with Sensar was inferior to the three aspheric IOLs at the majority of spatial frequencies. Tecnis yielded significantly better mesopic CSF at 1.5 and 3 cycles per degree spatial frequencies. Tecnis and AcrySof IQ provided significantly better visual function as compared to Sensar and Akreos AO, especially with smaller pupil size. However, this difference diminished with increasing pupil size.

To compare the outcomes and complications of alcohol-assisted versus mechanical corneal epithelial debridement for photorefractive keratectomy (PRK). This randomized controlled trial included 1,250 eyes of 625 patients undergoing PRK for correction of myopia and myopic astigmatism. Each patient was randomly assigned to alcohol-assisted or mechanical epithelial removal. A total of 658 eyes underwent alcohol-assisted epithelial removal while the epithelium was removed mechanically in 592 eyes. Mean spherical equivalent was -4.37±2.3 D in the alcohol group and -3.8±1.3 D in the mechanical group (P = 0.78). There was no significant difference in postoperative pain between the study groups (P = 0.22). Uncorrected visual acuity? 20/20 and? 20/40 was achieved in 90.9% versus 93.4% (P = 0.08), and 98.9% versus 99.5% (P = 0.36) of eyes in the alcohol and mechanical groups, respectively. Final refractive error within 1D of emmetropia was achieved in 90% versus 92.2% of eyes in the alcohol and mechanical groups, respectively (P = 0.23). Alcohol-assisted debridement required less time than mechanical debridement (96±18 vs. 118±26 seconds, P=0.035). There was no significant difference between the two groups in terms of early and late postoperative complications. Alcohol-assisted and mechanical epithelium removal are comparable in terms of efficacy and side effects. The method of epithelial debridement in PRK may be left to the surgeon's choice.

To investigate the association between senile corneal arcus and atherosclerosis risk factors in patients with recent acute myocardial infarction. In this cross sectional study, atherosclerosis risk factors including fasting blood sugar, total cholesterol, and triglyceride levels were measured in 165 patients with recent (less than three month's duration) acute myocardial infarction. Slitlamp examination was performed to detect corneal arcus. Associations between senile corneal arcus and atherosclerosis risk factors were assessed. Overall, 165 patients including 100 male and 65 female subjects with mean age of 62±10.3 years were evaluated. In 122 patients (74%), variable degrees of corneal arcus were observed. The presence of corneal arcus was significantly associated with age (P = 0.03) and high levels of total cholesterol (over 200 mg/dl, P < 0.01). After adjusting for age, arcus was not associated with sex (P = 0.10), hypertriglyceridemia (P = 0.09), fasting blood sugar (P = 0.06), or systemic hypertension (P = 0.08). Our study revealed that corneal arcus is associated with age and hypercholesterolemia in patients with recent acute myocardial infarction. No association was detected with sex, fasting blood sugar, hypertension, and hypertriglyceridemia.

To analyze the cost of glaucoma medical therapy and compare it with that of surgical management in Nigeria. The cost of glaucoma drugs and that of surgical therapy in patients who attended the eye clinic of the University of Benin Teaching Hospital, Benin City, Nigeria, between December 2002 and November 2008 were calculated over a 3 year period of follow-up. Costs of medical and surgical therapy were compared based on November 2008 estimates. One hundred and eight patients met the inclusion criteria of the study, of which, 90 patients (83.33%) received medical therapy and 18 patients (16.67%) underwent surgery. The most expensive drugs were the prostaglandin analogues, travoprost (Travatan) and latanoprost (Xalatan). The least expensive topical drugs were beta-blockers and miotics. The mean annual cost of medical treatment was US$ 273.47±174.42 (range, $41.54 to $729.23) while the mean annual cost of surgical treatment was US$ 283.78±202.95 (range, $61.33 to $592.63). There was no significant difference between the mean costs of medical and surgical therapy over the 3-year period (P = 0.37). Older age (P = 0.02) and advanced glaucoma (P < 0.001) were associated with higher costs of therapy. The cost of medical therapy was comparable to that of surgical therapy for glaucoma in Nigeria over a 3-year period.

To report the anatomical and functional outcomes of surgery for retinal detachment associated with chorioretinal colobomas. In this retrospective interventional case series, 28 eyes of 28 patients (including 18 male subjects) who had undergone surgery for retinal detachment associated with retinal colobomas were evaluated regarding the type of intervention, final visual acuity and final anatomical outcomes, as well as complications. Cases with less than 3 months of follow-up were excluded. Primary surgery included vitrectomy in 25 (89.3%) and scleral buckling in 3 (10.7%) eyes. The internal tamponade used in eyes undergoing vitrectomy was silicone oil in 23 (92%) eyes and 20% sulfur hexafluoride (SF6) in 2 (8%) eyes. Silicone oil was removed in 11 eyes (45.8%). Mean follow-up was 40±36 months. The mean number of operations per eye was 1.57±0.74 and the retina remained attached in 26 eyes (92.9%) at final follow-up. Mean preoperative visual acuity was 2.33±0.55 (range, 1.15-2.9) logMAR which significantly improved to 1.72±0.9 (range, 0.09-3.1) logMAR postoperatively (P < 0.001), however, final median visual acuity was counting fingers at 2 m. The most common complications were cataracts (100%) and ocular hypertension (46.4%). The most prevalent surgical procedure for treatment of retinal detachment associated with chorioretinal coloboma was pars plana vitrectomy and the most frequently used tamponade was silicone oil. Although anatomical success was satisfactory, functional outcomes were not encouraging which reflects the complexity of the condition and associated abnormalities.

To evaluate the risk factors associated with giant retinal tears. This retrospective study was performed on medical records of 150 patients who had undergone retinal detachment surgery. Age, sex, history of trauma, lens status (phakic, pseudophakic, or aphakic), and high myopia were evaluated in association with giant retinal tears. Of 150 patients with retinal detachments, 99 subjects (66%) were older than 30 years while 51 (34%) were 30 years of age or younger. Overall, 26 (17.3%) patients had giant retinal tears. Controlling for all variables, only age had a significant correlation with giant retinal tears. Each year of advancing age was associated with a 6% decrease in the incidence of giant retinal tears. Young age is a significant risk factor for development of giant retinal tears

Major advances in various disciplines of basic sciences including embryology, molecular and cell biology, genetics, and nanotechnology, as well as stem cell biology have opened new horizons for regenerative therapy. The unique characteristics of stem cells prompt a sound understanding for their use in modern regenerative therapies. This review article discusses stem cells, developmental stages of the eye field, eye field transcriptional factors, and endogenous and exogenous sources of stem cells. Recent studies and challenges in the application of stem cells for retinal pigment epithelial degeneration models will be summarized followed by obstacles facing regenerative therapy

To report an alternative treatment for metastatic tumors within the eye. CASE REPORT: Five intravitreal injections of bevacizumab (2.5 mg each) were performed in one eye of a 50-year-old woman with choroidal metastasis of lung carcinoma. Tumor size was reduced, pain disappeared, vision improved, and there were no secondary reactions. Vision improved from 20/40 to 20/20 and metamorphopsia decreased. Ten months after initiating treatment, an ultrasonographic study revealed no residual tumor, the choroid was normal in thickness and fluorescein angiography revealed a scar but no mass lesion. Intravitreal bevacizumab displayed beneficial effects in reducing tumor size and improving symptoms in this case of choroidal metastasis of lung carcinoma. The antineoplasic properties of this agent make it a viable alternative for treatment of metastatic choroidal tumors.

To report a case of Hermansky-Pudlak syndrome. CASE REPORT: A seven-year-old boy presented with marked generalized hypopigmentation, ocular exodeviation and nystagmus. He had history of easy bruising. Examination revealed green irides with marked transillumination, hypopigmented fundi and foveal hypoplasia. Further investigations disclosed platelet storage defect with adenosine diphosphate deficiency and abnormal aggregation compatible with Hermansky-Pudlak syndrome. The patient underwent strabismus surgery taking necessary precautions such as reserving platelet concentrates in case of a hemorrhagic event. Patients with albinism should be evaluated for Hermansky-Pudlak syndrome especially before surgery to prevent life-threatening complications.

Herein we report our experience with a simple technique for reducing the rate of silicone tube extrusion after nasolacrimal duct (NLD) intubation for congenital NLD obstruction. Medical records of children older than 2 years, with or without history of failed probing, who had undergone NLD intubation with a Crawford silicone tube over a period of 4 years were reviewed. In all subjects, one end of the Crawford tube was passed through a piece of scalp vein tubing followed by applying one or two knots. All Crawford tubes were removed after 3 months. Main outcome measures included complications such as tube extrusion, nasal discharge, crust formation and pyogenic granuloma formation. Fifty-seven patients, including 49 unilateral and 8 bilateral cases with mean age of 3.8±1.6 (range, 2 to 11.5) years were operated. No complications such as tube dislodgement, significant nasal discharge, crust or pyogenic granuloma formation occurred prior to Crawford tube removal. All silicone tubes were successfully removed from the nasal cavity. In conclusion, passing one end of the Crawford tube through a small piece of scalp vein tubing before knotting it in the nasal cavity seems to decrease the rate of tube extrusion which is the most common complication following NLD intubation in children.