Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Extensive investigations into the pathophysiology of glaucoma now reveal the role of multiple factors in the development of retinal ganglion cell death. A better understanding of the pathophysiological mechanisms involved in the onset and progression of glaucomatous optic neuropathy is crucial in the development of better therapeutic options. This review is an effort to summarize the current concepts in the pathophysiology of glaucoma so that newer therapeutic targets can be recognized. The literature available in the National Medical Library and online Pubmed search engine was used for literature review.

Background: While lens-sacrificing vitrectomy is the standard approach to manage Stage 5 retinopathy of prematurity (ROP), scleral buckling has been used to manage some cases of Stage 4. Lens-sparing vitrectomy was popularized by Maguire and Trese in selected cases of Stage 4 disease. Purpose: To assess the functional and visual outcomes after primary lens-sparing pars plana vitrectomy for Stage 4 ROP. Materials and Methods: In a retrospective, interventional, consecutive case series, the records of 39 eyes of 31 patients presenting with Stage 4 retinal detachment secondary to ROP who underwent primary two or three-port lens-sparing vitrectomy from January 2000 to October 2006 were evaluated. The outcomes studied at the final follow-up visit were the retinal status, lens and medial clarity and visual acuity . Favorable anatomical outcome was defined as the retinal reattachment of the posterior pole at two months after the surgery; and favorable functional outcome was defined as a central, steady and maintained fixation, with the child following light. Results: At mean follow-up of 15 months, 74% of the eyes had a favorable anatomical outcome with single procedure. The visual status was favorable in 63% . The lens remained clear in all the eyes at the last follow-up, and the media clarity was maintained in 87%. Intraoperative complications included vitreous hemorrhage, pre-retinal hemorrhage and retinal break formation. Conclusions: Lens-sparing vitrectomy helps to achieve a favorable anatomical and functional outcome in selected cases of Stage 4 ROP.

Purpose : To review the epidemiological characteristics, microbiological profile, and treatment outcome of patients with suspected microbial keratitis. Materials and Methods : Retrospective analysis of a non-comparative series from the database was done. All the patients presenting with corneal stromal infiltrate underwent standard microbiologic evaluation of their corneal scrapings, and smear and culture-guided antimicrobial therapy. Results : Out of 5897 suspected cases of microbial keratitis 3563 (60.4%) were culture-proven (bacterial - 1849, 51.9%; fungal - 1360, 38.2%; Acanthamoeba - 86, 2.4%; mixed - 268, 7.5%). Patients with agriculture-based activities were at 1.33 times (CI 1.16-1.51) greater risk of developing microbial keratitis and patients with ocular trauma were 5.33 times (CI 6.41-6.44) more likely to develop microbial keratitis. Potassium hydroxide with calcofluor white was most sensitive for detecting fungi (90.6%) and Acanthamoeba (84.0%) in corneal scrapings, however, Gram stain had a low sensitivity of 56.6% in detection of bacteria. Majority of the bacterial infections were caused by Staphylococcus epidermidis (42.3%) and Fusarium species (36.6%) was the leading cause of fungal infections. A significantly larger number of patients (691/1360, 50.8%) with fungal keratitis required surgical intervention compared to bacterial (799/1849, 43.2%) and Acanthamoeba (15/86, 17.4%) keratitis. Corneal healed scar was achieved in 75.5%, 64.8%, and 90.0% of patients with bacterial, fungal, and Acanthamoeba keratitis respectively. Conclusions : While diagnostic and treatment modalities are well in place the final outcome is suboptimal in fungal keratitis. With more effective treatment available for bacterial and Acanthamoeba keratitis, the treatment of fungal keratitis is truly a challenge.

Background : Diagnosis of amblyopia in preverbal strabismic patients is frequently made by binocular fixation preference (BFP) testing. The reports on reliability of BFP are equivocal. This study evaluated the reliability of BFP testing in patients with horizontal strabismus. Materials and Methods: This prospective observational study included patients with manifest, horizontal, comitant deviation >10 prism diopter (PD). Inter-eye acuity difference (IEAD) was calculated by converting Snellen visual acuity to logMAR and was compared with BFP testing. The fixation behavior of the non-preferred eye was evaluated by a single investigator as central or uncentral, steady or unsteady and maintained or unmaintained. Amblyopia was defined as the IEAD of >0.2 logMAR. Results: Of total 61 patients 36 were females and 36 had convergent squint, mean age 9.8 years. The correlation of BFP testing with IEAD was good for esotropia and exotropia. The sensitivity, specificity, positive and negative predictive value of central, steady, maintained (CSM) grading was 93%, 78%, 79%, and 93% respectively. Sensitivity and negative predictive values were higher in children aged four to nine years and anisometropia >1 diopter. The correlation between IEAD and lower grades of BFP testing was poor. Conclusions: CSM grading for BFP testing is useful for the detection of strabismic amblyopia but not useful to differentiate the depth of the amblyopia.

Purpose : To compare the psychosocial consequences of horizontal comitant strabismus in children between the families of urban and rural India. Materials and Methods : In this cohort study, an eight-question quality-of-life instrument was administered by trained staff to the guardians of strabismic children from rural and urban areas by a live interview. Results : This study included 93 strabismic-children aged 4-16 years of which 52 were females. Forty-one had esodeviation and 52 had exodeviation. Seventy per cent parents were extremely distressed due to squint, 65% were extremely distressed due to people's remarks, 65% were extremely worried, 55% children were extremely distressed due to people's remarks, 57% children were severely ostracized, 38% had severe difficulty in communication and 50% had difficulty to cope; 64% parents were not advised a corrective surgery. The difference between families from rural and urban areas, or whether a male child was affected or a female child or for an esodeviation or an exodeviation was statistically not significant. The questionnaire had a good internal consistency (Cronbach's Alpha = 0.71). Conclusions : There was a significant negative psychosocial and emotional impact of childhood strabismus that was not affected by the rural or urban location of the family or the gender of the strabismic child or type of the deviation. The quality-of-life instrument can be used as part of the clinical examination for strabismic children.

Aims: The tear ascorbate owing to its high concentration, functions as an effective antioxidant against the oxidative damage of cornea. Contact lens wearers (CLW) are prone to oxidative stress due to the lens-induced hypoxic conditions. A pilot study was done to compare the tear ascorbic acid level and the total antioxidant capacity give as in normal and CLW. Materials and Methods: In this study 21 CLW (Mean age 23 ± 3 years ; M-2, F-19), who were daily wear users, with duration of wear not more than four years, along with age-matched 28 controls (Mean age 28 ± 3 ; M-15, F-13) were recruited in the study for collection of reflex tears using Schirmer's strip. Ascorbic acid in tears was determined using high-performance liquid chromatography (HPLC), total antioxidant capacity (TAC) and total protein assay by spectrophotometric analysis. Results: CLW showed no significant change in the tear ascorbic acid levels (0.4 ± 0.26 mM) compared to the control subjects (0.61 ± 0.59 mM). The amount of ascorbic acid in tears did not correlate with the TAC or the total protein of the tears. The mean TAC in CLW was 0.69 ± 0.16 mM, with a total protein of 1.35 ± 0.46 mg/ml while in controls it was 0.7 ± 0.18 mM and 1.21 ± 0.47 mg/ml respectively . Conclusions: Soft contact lens wear did not show any significant change in tear ascorbic acid, TAC and total protein levels compared to controls.

Background : We present a series of patients with diabetes mellitus (DM) who attended an eye hospital in Sana, Yemen during 2004. Aim: To determine the magnitude and risk factors of diabetic retinopathy (DR). Design: Cross-sectional study. Materials and Methods: Ophthalmologists assessed vision, ocular pressure, ocular media and posterior segment to note ocular manifestations among patients with DM. DR was graded by using bio-microscope and Volk lens. The prevalence and 95% confidence interval of ocular complications of DM were calculated. Risk factors of DR like age, sex, duration of diabetes and hypertension were evaluated. Statistical a0 nalysis : Univariate and multivariate analysis. Results : Our series comprised 350 patients suffering from DM. The duration of diabetes was ≥15 years in 101 (29%) patients. Physician was treating 108 DM patients with insulin. The prevalence of DR was 55% (95% CI 49.6-60.1). The proportions of background diabetic retinopathy (BDR), preproliferative diabetic retinopathy (PPDR), proliferative diabetic retinopathy (PDR) and diabetic macular edema were 20%, 13%, 17% and 22% respectively. The prevalence of blindness among DM patients was 16%. The prevalence of cataract and glaucoma was 34.3% and 8.6%. Duration of DM was the predictor of DR. One-fifth of the patients had sight-threatening DR and needed laser treatment. Conclusions : DR was of public health magnitude among our patients. An organized approach is recommended to address DR in the study area.

Objective: To determine vitamin A-first dose supplement coverage in children aged 12-23 months and to find out its correlates with selected variables . Materials and Methods: The 30-cluster sampling technique based on probability proportional to size advocated by the World Health Organization was used to assess vitamin A-first dose supplement amongst 210 children in the age group of 12-23 months residing in slums of a randomly selected municipal zone of Delhi during October to November 2005. Results: Only 79 (37.6%) children out of 210 had received vitamin A-first dose supplement. Further analysis of 79 children was carried out with regard to selected variables like religion, gender, birth order, place of birth, immunization status and literacy of mother. These analyses showed that 71 (89.9%) were Hindu and eight (10.1%) were non-Hindu ( P = 0.04). Nearly 44 (55.7%) males and 35 (44.3%) females had received vitamin A ( P = 0.74). The proportion of children born in a health institution who received first dose (57%) of vitamin A supplementation was significantly higher than of those who were born at home (43%) ( P < 0.001). Similarly, higher proportion of children with birth order-one (48.1%) in comparison to birth order-three or above (26.6%) received vitamin A ( P < 0.001). Thirty children though fully immunized for vaccine-preventable disease up to the age-of-one year had not received vitamin A-first dose supplement, suggesting that an opportunity had been missed. The association between receipt of vitamin A by the child and literacy status of mother was found to be significant ( P < 0.001). Conclusion: The study reflects low coverage of Vitamin A supplement.

We describe a vertical lid split orbitotomy approach to perform optic nerve sheath fenestration which was done in a patient with idiopathic intracranial hypertension. A vertical lid split incision was used to enter the superomedial orbit and approach the optic nerve sheath. This approach resulted in a successful nerve sheath fenestration, with improvement in the patient's symptoms. The vertical lid split incision provides access to the optic nerve sheath with minimal morbidity and may be an option for optic nerve sheath decompression.

Endogenous fungal endophthalmitis is most commonly caused by Candida species and usually occurs in patients with chronic diseases such as diabetes mellitus and renal insufficiency. Voriconazole, a broad-spectrum triazole antifungal agent, attains therapeutically significant concentrations in the vitreous cavity after systemic administration. We report, the successful management of presumed endogenous Candida endophthalmitis in a patient with multiple diseases and unstable systemic status with oral voriconazole. Though fungal endophthalmitis has been successfully treated with a combination of intravenous and intravitreal voriconazole, to the best of our knowledge this is the first report in ophthalmic literature (Medline Search) on the treatment of fungal endophthalmitis with only the oral route of administration of voriconazole.

Scleral ulceration after ocular surgery is a rare but serious complication. Determination of the underlying systemic and local causes is critical for treatment. An unusual case of ischemic scleral ulceration after vitreoretinal surgery in a diabetic patient is reported. Patient was successfully treated with a pedicle conjunctival graft.

The milky sap or latex of Euphorbia plant is highly toxic and an irritant to the skin and eye. This report illustrates the spectrum of ocular inflammation caused by accidental inoculation of latex of Euphorbia plant. Three patients presented with accidental ocular exposure to the milky sap of Euphorbia species of recent onset. The initial symptoms in all cases were severe burning sensation with blurring of vision. Visual acuity reduced from 20/60 to counting fingers. Clinical findings varied from kerato-conjunctivitis, mild to severe corneal edema, epithelial defects, anterior uveitis and secondary elevated intraocular pressure. All symptoms and signs had resolved by 10-14 days with active supportive medication. People who handle Euphorbia plants should wear eye protection. It is always advisable to ask the patient to bring a sample of the plant for identification.

We report a case of aniridia associated with congenital aphakia and secondary glaucoma. A 35-year-old male presented with aniridia, congenital aphakia and secondary glaucoma in both eyes. After an unsuccessful medical management, he underwent trabeculectomy with mitomycin C and anterior vitrectomy under local anesthesia in his left eye. Postoperatively, at the end of six months, intraocular pressure (IOP) in his left eye was controlled without medications. This case highlights the rare association of aniridia with congenital aphakia and secondary glaucoma.

We describe three patients with bilateral, presumed human immunodeficiency virus (HIV)-induced optic neuropathy. The above diagnosis was made by exclusion of infectious agents and neoplasms by detailed clinical and laboratory investigations. All patients had decreased visual acuity, pale optic discs and constriction of visual fields. Improvement was documented in all three patients for visual acuity and in one patient for visual fields following treatment with highly active antiretroviral therapy (HAART). Optic neuropathy in HIV-positive patients does not necessarily carry a poor prognosis even when a treatable cause is not found. This article emphasizes the effectiveness of HAART in presumed HIV-induced optic neuropathy.

Schwannoma, also referred to as neurilemmoma, is a benign tumor of peripheral nerve arising from Schwann cells that form the neural sheath. Schwannoma of ophthalmic interest is rare although it has been reported in relation with the orbit, and less frequently with the uveal tract and conjunctiva. Isolated eyelid schwannoma is extremely uncommon. Up until now, only eight cases have been reported in literature. Herein, we report two cases of eyelid schwannoma.

A 29-year-old woman who underwent laser in situ keratomileusis (LASIK) for myopic astigmatism in both eyes presented with severe pain, photophobia and decreased visual acuity in the left eye eight days after surgery. Examination revealed severe anterior uveitis with fibrinous exudates in the anterior chamber, flap edema and epithelial bullae. Laboratory investigations for uveitis were negative and the patient required systemic and intensive topical steroids with cycloplegics to control the inflammation. This case demonstrates that severe anterior uveitis may develop after LASIK and needs prompt and vigorous management for resolution.