Evaluation of visual deficits in different types of amblyopia at rural tertiary setup

Abstract

Introduction: Amblyopia is defined as unilateral or bilateral dimness of vision caused by form vision deprivation and/or abnormal binocular interaction, is the most common cause of preventable monocular blindness and nearly all-amblyopic visual loss is reversible with timely detection and appropriate intervention. The conditions leading to functional amblyopia are well known and include strabismus, anisometropia, astigmatism, hypermetropia, cataract, and other forms of stimulus deprivation.

Material &Method: The present hospital based cross sectional study has been carried out in Department of Ophthalmology at Acharya Vinoba Bhave Rural Hospital attached to Jawaharlal Nehru Medical College, Sawangi (Meghe), Wardha, a constituent of Datta Meghe Institute of Medical Sciences (Deemed University), Nagpur during the period from September 2012 to August 2014. 100 eyes of 91 patients having Amblyopia or amblyogenic factor (strabismus or anisometropia) in outdoor and indoor patients were selected for the study.All patients were enrolled in the study after due consideration of various exclusion criteria for selection.

Results: The mean age of the study population was 15.00 ± 5.74 years, range 6-30 year. The present study found amblyopia to be more common in males than females. All the patients included in this study had one of the diagnoses from strabismic amblyopia, anisometropic amblyopia, isometropic amblyopia and stimulus deprivation amblyopia. Out of these maximum number of eyes was found to have anisometropic amblyopia (37%) and strabismic amblyopia (36%). Maximum numbers of eyes were seen with0.9-1.0 visual acuity (in LogMAR units).It was found to be highly significant in almost all except between strabismic and stimulus deprivation amblyopia; and between anisometropic and isometropic amblyopia.The present study found colour vision to be normal in all the various types of amblyopia. Most eyes were found to have hyperopic astigmatism/hyperopia (56%) followed by myopic astigmatism/myopia (31%) while mixed astigmatism was least common (13%). Maximum numbers of eyes were seen with 0.00 – 0.15 contrast sensitivity. 43% had normal while 57% had abnormal stereopsis.

Conclusion: Amblyopia and associated strabismus can have devastating psychosocial and economic fallouts. Knowledge about the sub-types of amblyopia is important because the clinical presentations, management and outcomes of these different types are different. The data in the present study could be used to enhance screening efforts in an organized manner in those health-care groups which come in regular contact with infants and young children.