Comparison of Techniques for Correction of Chin-down Vertical Abnormal Head Position Associated with Infantile Nystagmus Syndrome

Abstract

We evaluated the relative effectiveness of combined recession-resection of vertical rectus muscles versus superior rectus recession with inferior oblique weakening for patients who underwent surgical correction of chin-down abnormal head position (AHP) associated with infantile nystagmus syndrome (INS). Retrospective interventional case series. This is a review of 22 patients who underwent surgical correction of chin-down vertical AHP associated with INS at an academic institution. The primary outcome was collapse of AHP. Unfavorable outcomes included repeat surgery and induced strabismus, in addition to failure of collapse of AHP. Twenty-two patients had chin-down AHP. Recession-resection (bilateral superior rectus recession 6-9mm; bilateral inferior rectus resection 5-9mm) was performed in 11 cases; weakening of both elevators (bilateral superior rectus recession 5-8mm, bilateral inferior oblique recession or myectomy) occurred in 11 cases. Unfavorable outcome rates were 64% (7/11) compared with 18% (2/11), respectively (P= .03). Reoperation was performed for 6 of 22 patients. Five patients were from the recession-resection group, namely 3 for induced V-pattern esotropia, 1 for alternating esotropia, and 1 to correct recurrent AHP. The last of the 6 who required reoperation was in the elevator weakening group, and required correction of a recurrent AHP (P= .06). While recession-resection of the vertical recti and weakening of both elevators each produce acceptable collapse of chin-down AHP, the former frequently induces a V-pattern esotropia requiring reoperation.