Multiple vision disorders may occur after concussion including injury to the systems that control binocular vision including: Convergence insufficiency and Accommodation insufficiency
In order to obtain a single binocular vision, simultaneous movement of both eyes in opposite directions is required.
To look at an object close by such as when reading, the eyes must rotate towards each other (convergence).
Convergence insufficiency is the reduced ability to converge enough for near vision and is a common visual dysfunction seen after concussion.
One of both eyes may also turn outward.
May lead to complaints with reading such as diplopia, blurry vision, eyestrain, and skipping words or losing one's place.
Patient or parent may also report other difficulties such as becoming more easily fatigued when reading, needing to squint and/or having disinterest in reading.
Take home: consider testing convergence in patients with some of these complaints in setting of acute or subacute head trauma.
References
Master CL, Bacal D, Grady MF, Hertle R, Shah AS, Strominger M, Whitecross S, Bradford GE, Lum F, Donahue SP; AAP SECTION ON OPHTHALMOLOGY; AMERICAN ACADEMY OF OPHTHALMOLOGY; AMERICAN ASSOCIATION FOR PEDIATRIC OPHTHALMOLOGY AND STRABISMUS; and AMERICAN ASSOCIATION OF CERTIFIED ORTHOPTISTS. Vision and Concussion: Symptoms, Signs, Evaluation, and Treatment. Pediatrics. 2022 Aug 1;150(2):e2021056047.
