An infant with a large-angle esotropia shows jerk nystagmus that diminishes sharply when the eyes are adducted, and the child adopts a face turn to maintain adduction. The underlying mechanism and preferred surgical strategy are:

• A Weakness of convergence; large bilateral lateral rectus recession
• B Nystagmus blocked by adduction; large bimedial recession augmented with Faden sutures ✓
• C Superior oblique overaction; bilateral Harada-Ito procedure
• D Accommodative spasm; miotic drops with bifocal glasses

Explanation

In nystagmus blockage syndrome, innervation to converge and hold the eyes in adduction damps the nystagmus, so the child uses a face turn to keep the fixing eye adducted, producing a very large esotropia. Because the deviation is driven by this active mechanism, standard recession doses undercorrect; large bimedial recessions combined with posterior fixation (Faden) sutures are required to control both the squint and the head posture.

Reference: Khurana Comprehensive Ophthalmology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.