Purpose: This study aimed to investigate the surgical outcomes of nonadjustable Harada-Ito surgery under general anesthesia.
Methods: Twenty-two patients who underwent nonadjustable modified Harada-Ito surgery under general anesthesia were reviewed retrospectively. Among them, 21 out of the 22 patients who were followed up for 6 months after surgery were included in this study. Subjective cyclotorsion (double Maddox rod test) and objective cyclotorsions (fundus photography) were measured. Success of the surgery was defined as follows: success (the patients do not acknowledge diplopia at any direction), partial (the patients feel diplopia at a specific direction, but they do not feel discomfort in routine life), and fail (the patients feel diplopia in primary gaze, hence requiring a thorough investigation).
Results: The mean age of the patients (18 male and 3 female) was 56.5 years (range, 40-77 years). Based on the alternate prism cover test, the patients had 4.2 ± 3.0 prism diopters of vertical deviation. The corrected amounts of cyclotorsion based on the double Maddox rod test and fundus photography were 14.8° ± 7.5° and 9.8° ± 7.9°, respectively, and were significantly different between the two methods (p = 0.006). After the surgery, 20 out of the 21 patients (95.2%) completely recovered from diplopia in the primary gaze. However, among the 20 patients, seven complained of diplopia in the secondary gaze (down gaze, four patients; head tilt gaze, three patients). The success group had a smaller preoperative subjective excyclotorsion than the partial and fail groups (12.6° ± 2.5° and 21.0° ± 8.9°, respectively; p = 0.046).
Conclusions: Nonadjustable modified Harada-Ito surgery under general anesthesia has favorable success rate, and preoperative subjective excyclotorsion can be a prognostic factor in patients with bilateral superior oblique palsy.
Keywords: General surgery; Harada-Ito surgery; Strabismus; Superior oblique palsy.