Outcomes of Nishida Muscle Transposition Procedure for Abducens Nerve Palsy.

Abstract

Purpose: To evaluate the motor outcomes after Nishida procedure for unresolving sixth nerve palsy (SNP).

Study design: Retrospective case series METHODS: A retrospective chart review was conducted on patients who underwent Nishida procedure with prior or simultaneous medial rectus recession (Mrc) for SNP and completed >3 months follow-up. Operative details including the position of sutures, ductions, versions, and angles of misalignment were tabulated. Success was defined as orthophoria within 8Δ.

Results: Thirty-four patients were identified. Mean age was 24.4±19.2 years. Trauma was the most common cause (24 patients, 70.5%). Mean preoperative angle of deviation was 44.7±7Δ (range, 25 to 60Δ) in unilateral cases (n=32) and 90Δ in bilateral cases. One case had prior Mrc. Simultaneous Mrc and Nishida procedure was performed in all other cases (33) (mean recession, 4.6±1.2 mm). The Nishida sutures were placed 12 mm from the limbus in all cases. Mean follow-up was 10.3±9.1 months. Initial overcorrection >8Δ occurred in 8 cases (23.5%) and resolved spontaneously in 6 cases in the first 2-3 weeks after surgery. Residual esotropia >8Δ occurred in 4 cases (11.7%), all had sutures placed 5-7 mm from the lateral rectus borders versus <5 mm in successful cases. There was no relationship between the amount of Mrc and undercorrection. Final success rate was 82.3%. Mean postoperative angle was 1±6.5Δ (range, XT 15Δ to ET 20Δ). Induced vertical deviation occurred in 2 patients but resolved completely in 1 patient. Mean postoperative abduction deficit was -2.7±0.8.

Conclusions: Nishida procedure is an effective and self-adjusting procedure for the management of SNP. Care should be taken to properly place the sutures to reduce the risk of undercorrection.