Association of preoperative sensory monofixation with surgical failure in adult-onset divergence insufficiency–type esotropia

We investigated the frequency of sensory monofixation in patients with adult-onset divergence insufficiency esotropia and whether preoperative sensory monofixation was associated with surgical failure. Twenty-five patients with esotropia greater at distance than near who underwent bilateral medial rectus recessions were included. Near stereoacuity was measured preoperatively and 8 weeks postoperatively using the Randot Preschool test. Patients with best-corrected visual acuity worse than 0.3 logMAR in either eye or preoperative diplopia "rarely" or "never" in straight-ahead gaze at distance were excluded to minimize the inclusion of decompensated childhood strabismus. Sensory monofixation was defined as stereoacuity of 200 arcsec or worse and bifixation as 40 or 60 arcsec. Surgical failure was defined as esodeviation of >4Δ or exodeviation of >10Δ at distance or near, assessed 8 weeks (range, 6-17 weeks) postoperatively. We calculated the frequency of monofixation and surgical failure rates among patients with preoperative monofixation and those with preoperative bifixation. Preoperatively, sensory monofixation was common in divergence insufficiency–type esotropia (16 of 25 [64%]; 95% CI, 45%-83%). None of those with preoperative sensory monofixation had surgical failure, which does not support an association of surgical failure with preoperative monofixation.