Purpose: To evaluate outcomes of one muscle surgery for treatment of congenital superior oblique palsy (SOP) with Knapp Class V. Methods: Medical records were retrospectively reviewed for the patients with the congenital SOP type V who underwent surgical treatment through one muscle surgery between July 2015 and September 2020. The surgical procedure was resection-recession on the contralateral inferior rectus muscle of the hypertrophic or paretic eye. Vertical alignment at nine cardinal gaze positions, and resolution of the abnormal head posture were evaluated pre- and postoperatively. The follow-up was scheduled regularly at postoperative day 1, 1 week, 1 month, and followed by 2-month intervals until 18 months. Results: Twelve patients were included in this study, with a mean age of 6.4 years (range from 3 to 10 years). The mean follow-up period was 10.5 months after surgery (range from 6 to 18 months). The average vertical deviation at primary position was 6.33△ ± 2.93△ preoperatively and 0.75△ ± 1.14△ postoperatively ( p < 0.05). The average vertical deviation at downgaze was 23.33△ ± 4.75△ preoperatively and 1.92△ ± 1.62△ postoperatively ( p < 0.05). All patients had an abnormal head position preoperatively. Postoperative results indicated that the patients’ abnormal head position had been improved significantly. Conclusions: The surgical procedure of resection-recession on a single inferior rectus muscle is a successful intervention for the correction of superior oblique palsy (SOP) with Knapp Class V.
Internal organization of medial rectus and inferior rectus muscle neurons in the C group of the oculomotor nucleus in monkey
