Introduction: Pterygium is a degenerative condition of the subconjuctival tissue, which proliferates as vascularised granulation tissue to invade the cornea resulting in destruction of the superficial layer of the corneal stroma and bowman's membrane. This change in cornea leads to corneal opacity, visual impairment and significant induced astigmatism. The ensuing pathologic changes consist of elastoid degeneration of collagen and the appearance of subepithelial fibrovascular tissue Objective: To measure the change in corneal astigmatism after pterygium surgery and the relationship of astigmatism with respect to size of pterygium. Methodology: Hospital based prospective, non-randomized study, comprising 61 eyes of 56 patients who underwent pterygium excision and autologus conjuctival graft during the period October 2009 to September 2010. A total of 56 participants were enrolled and followed upto 3 months after surgery. Corneal topography was used to measure corneal astigmatism before and after pterygium surgery. Results: The mean age of patient was 46.11 years, standard deviation was 18.86 Male: female ratio: 0.8:1 Preexisting induced astigmatism among study group patients was 2.6D and mean astigmatism after pterygium surgery was 0.8D. This finding was found to be statistically significant(P value <0.001). Over all change in mean astigmatism was 1D in our study. In grade I Mean astigmatism before surgery was 0.96D and Mean astigmatism after surgery was 0.46D, Changes in mean astigmatism after surgery was 0.50D. In grade II Mean astigmatism before surgery was 1.99D and Mean astigmatism after surgery was 0.54D, Changes in mean astigmatism after surgery was 1.45D. In grade III Mean astigmatism before surgery was 10.71D and Mean astigmatism after surgery was 3.10D, Changes in mean astigmatism after surgery was 7.61D. The change in mean astigmatism is greatest in patients with grade III pterygium. Conclusion: After pterygium surgery astigmatism significantly reduces and astigmatism increases with the grade of pterygium.

Background Vernal keratoconjunctivitis (VKC), an allergic disease, has a known association with ectatic disorders of the cornea. Pellucid marginal degeneration (PMD) is a bilateral, asymmetrical, ectatic disorder of the cornea characterized by inferior corneal thinning. We report a case of sensory exotropia due to PMD in association with VKC. Case Details A 19-year old boy with a history of VKC presented with exotropia of the right eye of 3 years’ duration. His unaided vision in his right eye was 1/60 and in his left eye it was 6/36. On examination, both eyes had high against the rule astigmatism, which was more in the right eye. There was exotropia of 15º (40 prism diopter base in) in the right eye with suppression (Worth four dot test). Corneal examination in both eyes showed inferior band thinning, 2 mm above the inferior limbus, extending from 4 to 8 clock hours, with bulging of the cornea just above the thinning. The clinical features were suggestive of PMD, which was supported by his corneal scans – Atlas, Pentacam, and Optovue. Although he was undergoing treatment for VKC, the onset of PMD and decrease in vision went unnoticed. The asymmetric error which was not corrected during the sensitive period of visual development led to sensory exotropia. Conclusion A child with VKC should undergo regular refraction so as not to miss any ectatic changes occurring in the cornea. A delay in diagnosing corneal ectasia may negate the possibility of collagen cross-linking which prevents progression of ectasia. If visual rehabilitation is delayed beyond the age of visual maturation, it can lead to strabismus, suppression, and loss of binocular function.

Introduction: Cortical visual impairment denotes vision loss from pathology posterior to the lateral geniculate nucleus. The pathology may involve the optic radiations, as well as the occipital cortex. Objective: To find out the profiles of cortical visual impairment patients visiting the pediatric outpatient department. Materials and Methods: The study is a hospital based retrospective study in which all consecutive patients diagnosed with cortical visual impairment were included. A total of 40 patients were collected. Detailed history taking and clinical examination was done. Visual acuity was taken by fixation and follows method. Among 40 patients, only two patients were advised to use glass and the rest did not have significant refractive error. Myopia ranged from (-2D to -5D) and five patients were myopic. Astigmatism ranged from (-0.5 to -2.5 x 108°) and 10 patients had astigmatism. Suspected patients were advised for Computed Tomography/ Magnetic Resolution Imaging (CT/MRI) of the brain. Results: The male: female ratio was 3:2, the age group ranged from 4 months to 8 years old, antenatal checkup history was uneventful in 77.5% cases, history of birth asphyxia was present in 87.5% cases, postnatal checkup history was eventful in 67.5%, associated systemic illness was present in 60%, anterior segment examination was normal in 92.5%, posterior segment examination was normal in 72.5%, CT/MRI findings were abnormal in 57.5% and was not done in 30% of cases. Antenatal history was described as uneventful if there was absence of diabetes mellitus, hypertension, fever and intake of any medicine. Postnatal history was described as uneventful if there was absence of febrile convulsion, meningitis, encephalocele, encephalopathy, epilepsy or hydrocephalus. Conclusion: Birth asphyxia and postnatal infections are the major causes for cortical visual impairment. We can mitigate cortical visual impairment by limiting birth asphyxia and postnatal infections.

Introduction: Cortical visual impairment (CVI) in children is a retro chiasmal visual tract disorder where there is with an impairment in the visual acuity and/or functionality of vision-guided task, including motor planning in the presence of normal ocular findings or minimal ocular morbidity. The study was conducted to assess the knowledge about CVI among ophthalmologists practicing in Nepal. Materials and methods: This was a cross sectional study. Data collection was done by administering a preformed, validated questionnaire that was sent via email to all the ophthalmologists registered under the Nepal Ophthalmic Society. The email mentioned the aim of the study along with the questionnaire.  Results: A total of 146 (37.82%) ophthalmologists responded to the questionnaire. Forty four percent of the participants were general ophthalmologists, 28% were pediatric ophthalmologists and 67% were ophthalmologists from other subspecialty. The median age of participants was 37.6 years. Most of the ophthalmologist had a good knowledge about the cause, common risk factors, clinical risk factors, management and prognosis of CVI. However only 29.5% of participants were aware of the investigation of choice for diagnosing CVI and 31.7% were aware of the leading causes of visual impairment in the developed countries. The study also established that the knowledge score was higher in pediatric ophthalmologists than the general ophthalmologist and ophthalmologists from other specialties. Conclusion: Most of the ophthalmologists had a good knowledge about the cause, common risk factors, clinical features, management and prognosis of CVI. However only a limited number of participants were aware of the investigation of choice for diagnosing CVI and the leading causes of visual impairment in the developed countries. Majority of the participants rarely examined patients with CVI which does not correlate with the high prevalence of perinatal hypoxia, the commonest cause of CVI, in our country.