Abstract
Abstract: :
Purpose: In a previous study of patients with superior oblique palsy (SOP), we found that 66 percent had an associated horizontal heterotropia or phoria. The purpose of this study was to determine the indications for combining horizontal muscle surgery with vertical surgery in patients with SOP. Methods: We performed a retrospective chart review of all patients diagnosed with unilateral SOP in our institution between August 1995 and February 2002. 209 eligible patients who met Park’s 3-step criteria and who had no history of previous strabismus surgery or other confounding ocular motility disturbance were included in the study. Of these, 96 (45.6%) required surgical treatment. Patient age ranged from 0.2 to 82.2 years (mean 33.6). The mean time for post-operative followup was 9.0 months. Surgical outcomes were compared between those patients who had combined vertical and horizontal surgery and those who had vertical surgery alone using the Student’s t-test. Results: Of the study population, 122 (58.4%) had a horizontal heterotropia or phoria in addition to vertical strabismus; 47 (22.5%) had esotropia and 75 (35.8%) had exotropia. For patients requiring strabismus surgery, 29 patients had ≥ 8 prism diopters (PD) of horizontal misalignment. Of these 22 (75.9%) had vertical combined with horizontal surgery (V+H group). Although their initial deviation was greater, these patients had better surgical outcomes when compared with similar patients who had vertical surgery alone (V group). The V+H group had a final horizontal deviation of 2.18 PD (± 0.81 PD) compared to 6.85 PD (± 1.37 PD) in the V group (p < 0.01). Postoperative vertical alignment in the V+H group was also superior with a final vertical deviation of 3.7 PD (+/- 0.9 PD) compared to 6.8 PD (+/- 2.0 PD) for the V group, although this did not reach statistical significance (p= 0.12). Conclusions: These results suggest that those patients with SOP who have 8PD or more horizontal deviation may benefit from surgical correction of the horizontal deviation in addition to the vertical surgery.
Keywords: strabismus: treatment • strabismus