The magnitude and causes of amblyopia in children attending a paediatric tertiary eye clinic in dar es salaam Tanzania

Objective: To determine the magnitude of amblyopia among children attending the pediatric eye clinic at Muhimbili National Hospital. Materials and Methods: consecutive samplingof children fulfilling the case definition of amblyopia was done to recruit 140 children. Anterior and posterior segment examination, cycloplegic refraction and ocular alignment were done to determine the causes of amblyopia. Data was transferred into a computer program and analyzed with the help of the Statistical Package for Social Sciences version 20.0software.Frequencies, means and standard deviations were used to summarize data. A P-value of <0.05 was considered statistically significant for associations. Ethical approval was granted by the Ethics committee of Muhimbili University of Health and Allied Sciences. Results: A total of 1953 children attended the paediatric clinic during the study period. There were140/1953 (7.18%) children with amblyopia, where 78 (55.7%) were males and 62 (44.3%)were females. The mean age was 6.4(5.6-7.2) years. Sixty nine (49.3%) children presented early in the age group of ≤5 years. Refractive amblyopia was the most common type which affected 59/140 (42.2%) patients. Severe amblyopia was found in all types of amblyopia. However sensory deprivation was the leading cause of severe depth of amblyopia (78%). Esotropia was the commonest cause of strabismic amblyopia that occurred in 29/37 (78.4%) while Anisohyperopia was found in 15/59 (25.4%) patients and was the commonest cause of refractive amblyopia. Cataract was the main cause of sensory deprivation amblyopia which was found in 12/15 (80%) patients. Combined Strabismic and Refractive 18/29(65.5%) was the commonest cause of combined amblyopia. Conclusions: The magnitude of amblyopia in children attending the paediatric ophthalmology clinic at MNH is high where majority of affected patients present with severe depth of amblyopia. Refractive amblyopia was the most common type of amblyopia. Esotropia, cataract, anisohyperopia and combined strabismic and refractive were the commonest causes of amblyopia. Pre-school screening of children to enable early recognition and referral for appropriate management of children with refractive errors and cataract need be established to reduce the magnitude and severity of amblyopia.