A retrospective review of Harada-Ito procedures for superior oblique palsy

The Harada-Ito procedure aims to reduce symptomatic excyclotropia. We report a case series of unilateral and bilateral superior oblique (SO) palsies that underwent Harada-Ito procedures and our approach to surgical decision-making in these complex cases. Our surgical techniques are described, including the Fells modification of the Harada-Ito and our "plus" and "with resection" of the transposed portion of the SO tendon variations.

A retrospective review of Harada-Ito procedures was undertaken. Demographic data were extracted on diagnosis, etiology, and previous and subsequent strabismus surgery. Pre- and 3-month postoperative measurements and final visit outcome were recorded.

Twenty-nine patients underwent Harada-Ito procedures for unilateral (n = 10) or bilateral (n = 19) SO palsies. Twenty-seven patient notes were available for review of their measurements. In unilateral SO palsy, our surgery resulted in a near deviation change of mean (SD) 7.6PD (6.8) horizontal, 7.7PD (7.3) vertical, and 7.4 degrees (5.3) torsion. While Harada-Ito surgery in isolation resulted in a near deviation change of mean (SD) 2.3PD (1.7) horizontal; 7.3PD (3.3) vertical and 5.5 degrees (4.1) torsion.In patients with bilateral SO palsies, our surgery resulted in a near deviation change of mean (SD) 7.6PD (9.9) horizontal, 8.1PD (9.6) vertical, and 12.7 degrees (6.4) torsion. While Harada-Ito surgery in isolation resulted in a near deviation change of mean (SD) 6.8PD (6.0) horizontal; 2.4PD (1.1) vertical and 9.4 degrees (3.0) torsion.In unilateral SO palsy, two underwent further strabismus surgery. At the last available visit, 8/9 were discharged with BSV and 1/9 was discharged asymptomatic without BSV. In bilateral SO palsies, 7/19 underwent further strabismus surgery. At the last available visit, 15/19 were discharged with BSV, 3/19 were discharged asymptomatic without BSV and 1/19 required an occlusive contact lens.

Unilateral and bilateral SO palsies with symptomatic excyclotropia are challenging to treat. Nine patients (33%) required more than one surgical procedure to eliminate torsion and achieve BSV, even with our individualized approach for the Harada-Ito. Comparison of the outcomes of different Harada-Ito variations is difficult due to the complex and heterogeneous cohort. Most cases achieved BSV (23/27, 85%) or were asymptomatic (3/27, 11%) at final visit.