Combined retro-recession on a single muscle for the correction of incomitant vertical strabismus

To evaluate the effectiveness of the combined resection-recession technique in correcting incomitant vertical strabismus.

A retrospective study was conducted on four adult patients with incomitant vertical strabismus, treated using the resection-recession technique on the inferior rectus muscle, with the resection amount being at approximately 50% of the recession. Surgeries were performed under topical anaesthesia and sedation, using adjustable sutures, allowing for intraoperative adjustments. Deviation in prism dioptres (PD) was measured in primary position and in the incomitant position, both before and after surgery. Success was defined as a reduction in incomitance greater than 50% and the preservation of orthotropia in primary position.

Three patients were female and one was male, with a mean age of 58 years (range 38-80 years). The mean preoperative deviation in downgaze was 13 PD (range 10-16 PD), which reduced to 0.5 PD (range 0-1 PD) following surgery. The mean preoperative incomitance was 12 PD (range 10-14 PD), decreasing to 0.5 PD (range 0-1 PD) postoperatively (p < 0.05), representing a 95.8% reduction in incomitance. All patients achieved orthotropia in primary position. In one case, an intraoperative adjustment was necessary to correct a limitation in downgaze. No significant intraoperative complications were recorded.

The combined resection-recession technique appears to be effective and safe for the correction of vertical incomitant strabismus, achieving significant reduction in incomitance while maintaining alignment in primary position. The option for intraoperative adjustments may enhance surgical outcomes.