accommodative convergence
The involuntary convergence eye movement that accompanies accommodation when focusing on near objects.
Full Definition
Accommodative convergence refers to the automatic convergence eye movement that occurs as part of the near triad response when focusing on nearby objects. This synkinetic movement is neurologically linked to accommodation through shared neural pathways and helps maintain binocular single vision during near tasks. The accommodative convergence to accommodation ratio (AC/A ratio) is an important clinical measurement that can be abnormal in various binocular vision disorders. Understanding this relationship is crucial for managing patients with convergence insufficiency, accommodative esotropia, and other binocular vision problems.
Usage
Usage note: Part of the near triad; often measured as AC/A ratio in clinical practice.
In Context
- "The high AC/A ratio explained the patient's near esotropia with normal distance alignment." — pediatric ophthalmology report
- "Accommodative convergence was preserved despite the nuclear third nerve palsy affecting voluntary convergence." — neuro-ophthalmology examination