Combined Rectus Muscle Transposition With Posterior Fixation Sutures (Augmented Knapp Procedure) for the Surgical Treatment of Double Elevator Palsy.

Abstract

To evaluate the surgical results of full horizontal tendon rectus muscle transposition to the superior rectus muscle insertion, augmented by posterior fixation sutures, in patients with double elevator palsy. In this retrospective comparative study, 17 patients treated by the augmented Knapp procedure (study group) were compared with 28 patients treated by the standard Knapp procedure (control group). Pre-operative and postoperative vertical deviation in primary position, ocular motility, binocular function, and rate of reoperation were evaluated. The mean preoperative near and distance deviations (hypotropia) decreased by 93% and 97% in the study group and 68% and 69% in the control group, respectively. The improvement in near and distance deviation was statistically more significant in the study group than the control group (P = .001 for each parameter). The mean preoperative elevation deficiency in abduction and adduction improved by 64% and 66% in the study group and 37% and 39% in the control group, respectively. The improvement in elevation deficiency in abduction and adduction was statistically significantly greater in the study group than the control group (P = .001 and .04, respectively). Reoperation was required in 15 patients (54%) in the control group and 2 (12%) in the study group during the follow-up period of 26 ± 4 months. The postoperative improvement in near and distance deviation and elevation deficiency in abduction and adduction was significantly better in the augmented Knapp procedure than the standard Knapp procedure. This procedure demonstrated a stronger effect in the treatment of double elevator palsy. [J Pediatr Ophthalmol Strabismus. 2022;59(1):17-23.].