Title: To Study the Prevalence of Convergence Insufficiency: A Hospital Based Study
Authors: Dr Sakshi Sahni, Dr Abhishek Sachdeva, Dr Nalini Birpuri
DOI: https://dx.doi.org/10.18535/jmscr/v9i12.39
Abstract
Introduction
Convergence insufficiency (CI) is a binocular vision disorder characterized by difficulty in maintaining fusion while looking at a near target due to a tendency of the eyes to drift outwards. Exophoria that is greater at near than at distance, a remote near point of convergence(NPC), or decreased insufficiency is a common non-strabismic binocular vision disorder and is associated with symptoms such as headache, watering from eyes, visual fatigue and blurring of vision especially on near work. Earlier convergence insufficiency was defined as receding near point of convergence (NPC). Convergence insufficiency may be said to exist when the near point of convergence : more than 11 cm from the inter-ocular base line or 9.5 cm from the apex of cornea or when there is difficulty in attaining 30° convergence.(Duke-Elder 1973). convergence insufficiency (Scheiman, Wick 2002 ) is a condition in which there is -
- Exophoria at near;
- Orthophoria or low exophoria at distance;
- Receded near point of convergence;
- Reduced positive fusional vergence (PFV);
- Low AC/A ratio.
