Purpose: Fell's modification of the Harada-Ito (HI) procedure is often used to tackle subjective torsion usually following superior oblique palsy. There is limited published data on the longer-term outcomes and the effect on horizontal incomitance of the procedure. The purpose of this study is to report on the medium to long-term outcomes of the HI procedure.
Materials and methods: A retrospective review of 20 patients who had all undergone a single surgeon modified HI procedure to correct subjective torsion was undertaken. Follow-up data were analyzed in relation to stability of torsion measurements, the effect on vertical incomitance of horizontal deviation and the final treatment outcome.
Results: There was a significant reduction in median maximum torsion from preoperative to immediately post-op (p < .01) and there remained a significant difference in maximum torsion from preoperative measurement at both the 3-month (p = .02), and 12-twelve month (p = .01) follow-up. HI had a significant effect on associated V-pattern esotropia (p < .05).
Conclusion: The HI procedure is effective in eliminating subjective torsion initially and reducing incomitant horizontal deviation; however, regression toward preoperative torsion measurement occurs after time.
Keywords: Fourth nerve palsy; Harada Ito; superior oblique palsy; torsion.