Superior Rectus Muscle Recession for Residual Head Tilt after Inferior Oblique Muscle Weakening in Superior Oblique Palsy

PURPOSE: Residual head tilt has been reported in patients with superior oblique muscle palsy (SOP) after surgery to weaken the inferior oblique (IO) muscle. The treatments for these patients have not received appropriate attention. In this study, we evaluated the superior rectus (SR) muscle recession as a surgical treatment. METHODS: The medical records of 12 patients with SOP were retrospectively reviewed. Each of these patients had unilateral SR muscle recession for residual head tilt after IO muscle weakening due to SOP. The residual torticollis was classified into three groups on the basis of severity: mild, moderate, or severe. Both IO muscle overaction and vertical deviation, features of SOP, were evaluated in all patients. The severity of the preoperative and postoperative torticollis and vertical deviation were compared using a paired t-test and Fisher's exact test. RESULTS: The torticollis improved in nine of 12 (75%) patients after SR muscle recession. The difference between the preoperative and postoperative severity of torticollis was statistically significant (p = 0.0008). After surgery, the mean vertical deviation was significantly reduced from 12.4 prism diopters to 1.3 prism diopters (p = 0.0003). CONCLUSIONS: Unilateral SR muscle recession is an effective method to correct residual head tilt after IO muscle weakening in patients with SOP. This surgical procedure is believed to decrease head tilt by reducing the vertical deviation and thereby the compensatory head tilt.

Clinical features and outcomes of treatment for fourth nerve palsy

To evaluate the clinical features, etiology and outcomes of treatment for superior oblique [SO] palsy over a 10-year period at Labbafinejad Medical Center. A complete ophthalmologic examination with particular attention to forced duction test [FDT] and tendon laxity was performed in all patients preoperatively. The palsy was divided into congenital and acquired types. Overall, 73 patients including 45 male [61.6%] and 28 female [38.4%] subjects with mean age of 19.7 +/- 11.7 [range, 1.5-62] years, were operated from 1997 to 2007. SO palsy was congenital in 56 [76%] and acquired in 17 [24%] cases. The most common chief complaint was ocular deviation [52.1%]. FDT was positive in only 7 [9.7%] cases. Other clinical findings included amblyopia [19.2%] head tilt [13.7%], chin down position [4.1%], facial asymmetry [6.8%] and tendon laxity [2.7%]. Mean preoperative vertical deviation was 16.1 prism diopters [PD] which was decreased to 1.9 PD postoperatively. Mean exotropia and esotropia were 15 and 13.9 PD respectively before the operation and both decreased to 1.5 PD of horizontal deviation postoperatively. The most common type of SO palsy based on Knapp's classification was type 3 [42.5%]. The most common operated muscle was the inferior oblique [83.6%] and the most common type of operation was inferior oblique myectomy [83.6%]. The success rate for initial surgery was 84% and was increased to 96% with a second intervention. The most common form of SO palsy requiring surgical intervention was congenital which occurred most frequently in young males. Most cases of SO palsy can be successfully treated with a single surgical procedure