Strabismus and Amblyopia


Vision involves an interaction of the eyes, which receive visual stimuli, and the brain which creates the clear images. Vision develops during early childhood and is usually complete by 6 to 8 years of age. Amblyopia is a condition whereby the vision in one eye is reduced because vision has not developed normally. This reduced vision cannot be corrected with glasses. Amblyopia has a prevalence of approximately 3% and is the leading cause of preventable blindness in people under the age of 40. Several underlying conditions lead to amblyopia, of which a major one is strabismus (squint). Strabismus is the misalignment of the two eyes which has a prevalence of approximately 4% in infants and young children across the world. Strabismus and amblyopia are treatable in most cases if detected early enough and provided the appropriate treatment is given. If amblyopia is not treated by the age of 7 or 8, it becomes irreversible.

Click here to read a recent article about strabismus detection written by Dr Simon Barnard for the UK’s Optician Magazine.

The American Association of Paediatrics, the American Association of Paediatric Ophthalmology and Strabismus as well as the UK National Screening Committee and similar bodies around the world recommend that children undergo vision screening at least by the age of 4-5. The problem lies in the fact that while it is very desirable to detect these conditions even in babies and infants, this pre-verbal (often uncooperative) population, is very difficult to screen and diagnose accurately and reliably. This is the reason why many cases of amblyopia and strabismus are detected at the age of 6 or more, when it is almost too late for effective treatment. Hence there is a need for reliable and practical automatic screening and diagnostic technologies for these conditions.


“An introductory lecture on the clinical uses of the Volk Eye Check” by Dr. Simon Barnard