Near Point of Convergence (NPC) Among Healthy Secondary School Students in Southwest Nigeria: Paediatric Ophthamology & Strabismus

M.A Ijaduola; B.A Olusanya; O Fasina; M.O Ugalahi

Authors

M.A Ijaduola Department of Ophthalmology, University College Hospital, Ibadan.
B.A Olusanya Department of Ophthalmology, University College Hospital, Ibadan.
O Fasina Department of Ophthalmology, University College Hospital, Ibadan.
M.O Ugalahi Department of Ophthalmology, University College Hospital, Ibadan.

Abstract

Background: The near point of convergence is the point at which lines of sight are directed when convergence is maximum.1The assessment of near point of convergence (NPC) is an important examination in the assessment of non strabismic binocular vision abnormalities. It is an important component in comprehensive eye evaluation and is also considered a diagnostic finding in the assessment of convergence insufficiency.2,3,4 It is also a diagnostic tool in evaluating traumatic brain injury. There is a huge variation in the normative data established for ophthalmic parameters of Near point of Convergence because of the differences in measurement technique. There is paucity of data for normative values in Nigeria hence the need to establish the normative values for Near Point of Convergence (NPC) among healthy secondary school students in southwest Nigeria.

Methods: This was a descriptive cross-sectional study was conducted among 8-21year old students in September/March 2016. A multistage sampling was used to pick a representative sample of students in public senior and junior secondary schools in Ido Local Government Area Ibadan. Eligible students with Visual acuity > 6/9in both eyes, normal ocular findings with no strabismus or non- strabismus binocular disorders were recruited. NPC was measured with RAF rule line, RAF rule accommodative target, penlight, and tip of pen.

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