PURPOSE: To study the effect of eye dominance on excyclotorsion in unilateral superior oblique palsy (USOP). STUDY DESIGN: Retrospective clinical study METHODS: Objective excyclotorsion was measured as the disc-to-fovea angle by fundus photography OU. Subjective excyclotorsion was determined with a major amblyoscope based on the difference in the earth vertical and subjective visual vertical. Eye dominance was determined by the hole-in-the-card method. A p-value ≤ 0.05 was considered statistically significant. SUBJECTS: Data of 24 USOP patients were retrospectively collected. The diagnosis was mainly made by the Parks 3-step method, history and the presence of characteristic excyclotorsion. When possible, orbital magnetic resonance imaging findings were obtained. RESULTS: The median angle of objective excyclotorsion in the paretic eyes was significantly larger than in the nonparetic eyes. Both median angles of objective/subjective excyclotorsion in the dominant eye were significantly smaller than those of the non-dominant eye. Patients were subdivided into two groups: group A, those whose paretic eye was the dominant eye (n = 13); group B, those whose paretic eye was the non-dominant eye (n = 11). The objective/subjective excyclotorsional angles of the paretic eye were significantly larger than of the non-paretic eye only in group B. CONCLUSION: In USOP the angle of excyclotorsion in the dominant eye is smaller than in the non-dominant eye. This may imply that the vertical sense of visual space is mainly adapted to the dominant eye, keeping the subjective vertical close to the earth vertical.
PURPOSE: To study the effect of eye dominance on excyclotorsion in unilateral superior oblique palsy (USOP). STUDY DESIGN: Retrospective clinical study METHODS: Objective excyclotorsion was measured as the disc-to-fovea angle by fundus photography OU. Subjective excyclotorsion was determined with a major amblyoscope based on the difference in the earth vertical and subjective visual vertical. Eye dominance was determined by the hole-in-the-card method. A p-value ≤ 0.05 was considered statistically significant. SUBJECTS: Data of 24 USOP patients were retrospectively collected. The diagnosis was mainly made by the Parks 3-step method, history and the presence of characteristic excyclotorsion. When possible, orbital magnetic resonance imaging findings were obtained. RESULTS: The median angle of objective excyclotorsion in the paretic eyes was significantly larger than in the nonparetic eyes. Both median angles of objective/subjective excyclotorsion in the dominant eye were significantly smaller than those of the non-dominant eye. Patients were subdivided into two groups: group A, those whose paretic eye was the dominant eye (n = 13); group B, those whose paretic eye was the non-dominant eye (n = 11). The objective/subjective excyclotorsional angles of the paretic eye were significantly larger than of the non-paretic eye only in group B. CONCLUSION: In USOP the angle of excyclotorsion in the dominant eye is smaller than in the non-dominant eye. This may imply that the vertical sense of visual space is mainly adapted to the dominant eye, keeping the subjective vertical close to the earth vertical.