Combined surgical treatment effective for superior oblique muscle palsy with large hypertropia

This retrospective study found that combined resection and anterior transposition of the inferior oblique muscle effectively treated unilateral superior oblique muscle palsy with large hypertropias from 20∆ to 25∆ in primary position.

The authors retrospectively reviewed the medical records of 27 consecutive patients operated on for unilateral superior oblique muscle palsy and hypertropia from 20∆ to 25∆ in primary position. They ranged in age from 3 to 41 years and all had overaction of the inferior oblique muscle. All patients underwent disinsertion of the inferior oblique muscle, and 4 mm of its distal end was resected and transposed to the lateral border of the inferior rectus muscle insertion.

Mean hypertropia in primary position was 22.6∆ preoperatively, which decreased significantly to 1.4∆ six months after surgery. Mean hypertropia on gaze to the contralateral side decreased significantly from 29∆ before surgery to 1.2∆ at six months. Before surgery, 22 patients had head tilt, which was resolved by the surgical procedure in 14 patients and reduced in the remaining 8 patients. The surgical success rate was 89 percent.

No patients developed hypotropia in primary position. Mild limitation of elevation was recorded in one patient. Four patients developed lower eyelid fullness, which the authors say was not functionally significant.

They say their results indicate that combined resection and anterior transposition of the inferior oblique muscle reduced hypertropia in primary position and on lateral gazes in these patients.