Partial rectus muscle transposition for strabismus with lateral rectus muscles paralysis

Abstract

To investigate surgical approach for paralytic strabismus with lateral rectus muscles paralysis and evaluate its clinical effects. Design retrospective, observational case series. 28 patients (31 eyes) who underwent augmented partial rectus muscle transposition (APRMT) in the treatment of paralytic strabismus with lateral rectus muscles paralysis from May 2009 to May 2011 at Eye & ENT Hospital of Fudan University were included in this study. The following data were analyzed: (1) The procedure that was performed, (2) The angle of deviation of primary position, (3) The presence of compensatory head posture, (4) The presence of diploma in the primary position, (5) The binocular single visual fields, (6) The motility of the affected eye. According to the results of rectus muscle forced traction test and examination before and after operation, among 31 eyes in 28 patients, 8 eyes were treated with APRMT, 10 eyes were treated with recession of antagonistic muscle of paralytic rectus muscle combined with APRMT, 7 eyes were treated with APRMT and recession of yoke muscle, 6 eyes were treated with APRMT and recession of yoke muscle combined with recession of antagonistic muscle. 17 among 28 patients were orthotopicin the primary position while others were in mild under correction with deviation no more than 10 prism degrees during 5 months (range: 3-8 months) follow-up in average. The diploma and abnormal head posture were eliminated in 26 patients except one patient who was appeared with 10 prism degrees under correction postoperatively and was resolved by wearing prisms thereafter. Binocular single visual fields were extended from 27.0° ± 6.4 ° preoperatively to 40.5° ± 4.8 ° postoperatively (t = -34.692, P < 0.001). Ocular movement was improved from -4.9 ± 0.4 to -2.9 ± 0.9 postoperatively (t = -13.418, P < 0.001). APRMT can safely and effectively correct the primary position in paralytic strabismus with lateral rectus muscles paralysis, eliminate the presence of diploma in primary position and abnormal head posture, and improve the ability of the ocular movement, furthermore, significantly expand the scope of binocular single visual fields. The results also demonstrate that rectus muscle forced traction test is a key measurement to determine the surgical procedure.