Abstract
Purpose: :
Surgical management of superior oblique palsy (SOP) is challenging because of vertical, horizontal and torsional misalignments. While there are many studies comparing the different surgical approaches for SOP, to our knowledge, none have specifically addressed the subgroup of these patients that present with large hyperdeviations in primary position. Our purpose is to report the surgical results of subjects with large hypertropias of 20 or more prism diopters (pd) due to unilateral SOP.
Methods: :
Retrospective review of the records of all patients in a single-surgeon practice with large hypertropias (>20 PD) secondary to SOP. Exclusion criteria included amblyopia or a history of previous surgeries. Preoperative and postoperative head posture, torsion measurements, and deviation in nine gaze positions were compared. The specific surgical procedure and the number of operations for each subject were also recorded. Criteria for surgical success included correction of head posture and primary position alignment between orthotropia and 6 pd of undercorrection. Follow up period ranged from 3 months to 16 years.
Results: :
Forty-two subjects met study inclusion criteria. The mean age was 38.3 years (range 7-87 years). Thirty-eight (90%) of surgeries were successful in the immediate post-operative period and 3 subjects were undercorrected. Two of these 3 subjects had surgery on only one muscle. Twenty-two (52%) subjects were aligned between 6 pd of undercorrection and orthotropia after one surgery. Mean preoperative alignment in primary gaze was 27.1 +/- 5.6 pd and mean postoperative alignment was 4.95 +/- 3.5 pd. Late overcorrections were noted in 9 (21%) subjects and 4 (9.5%) subjects had late undercorrections.Of the subjects who had surgery on only one muscle, 20% had a successful outcome with an average 67% reduction in hypertropia. 57% of subjects who had two or more muscles operated on had a successful result, with an average 90% reduction in hypertropia (p value =0.04). The highest success rate (65%) belonged to subjects who underwent inferior oblique and inferior rectus recessions followed by those who had this combination plus a Harada-Ito procedure (60%).
Conclusions: :
Unilateral SOP subjects with large deviations in primary position are relatively uncommon and challenging to treat. About half (55%) of the subjects did well with one surgery alone. Subjects who underwent inferior oblique recessions plus inferior rectus recessions and/or a Harado-Ito procedure had the best outcomes. All subjects who had only one muscle operated on required additional surgery.
Keywords: strabismus: treatment • strabismus