Long-Term Outcomes of Three Cases That Underwent a Muscle Transposition Procedure Without Tenotomy Caused by Abducens Palsy

摘要

Few reports have discussed long-term outcomes of muscle transposition procedures. In this study, cases with abducens palsy treated with a muscle transposition procedure were followed for 12, 25, or 26 years. The preoperative alignments were esotropia of 65 degrees, 47 prism dioptres (PD), and 24 PD, respectively. Orthophoria was postoperatively achieved in all cases. The postoperative alignment in one case deteriorated at 8 years postoperatively, although orthophoria were maintained in the other two cases. These findings indicate that it is possible that esotropia can recur even though orthophoria was maintained for several years postoperatively in some cases that underwent a muscle transposition procedure. INTRODUCTION Muscle transposition of the healthy superior and inferior recti is commonly performed in the case of severe abducens palsy. Many previous papers have reported that a muscle transposition procedure was effective for abducens palsy.1"8 However, the stability of the effectiveness long term has not been revealed because few reports have discussed follow-up for 10 years after a muscle transposition procedure for abducens palsy. Therefore, we report long-term outcomes (>10 years) of three cases that underwent a muscle transposition procedure due to abducens palsy. MATERIAL AND METHODS The Institutional Review Board of Shiga University of Medical Science approved this study, which was conducted in accordance with the tenets of the Declaration of Helsinki. All patients provided written informed consent. A muscle transposition procedure without tenotomy, which we previously reported, was performed in two cases (Case 1 and Case 2), which were followed for 26 and 25 years, respectively (Figure la^In this procedure, a suture was secured at the lateral margin of each split vertical rectus muscle and each sclera beside the superior or inferior margin of the lateral rectus (LR) muscle. The lateral half of each vertical rectus muscle belly was transposed and anchored to the sclera. In the other case (Case 3), which was followed for 12 years, a muscle transposition procedure without tenotomy or muscle splitting, which we also reported, was performed (Figure lb).2'3 In the procedure, a suture was secured at the temporal margin of both the vertical rectus muscle and each sclera at the superotemporal or inferotemporal quadrant. Each vertical rectus muscle was transposed and anchored to the sclera.