Combining rectus muscle recessions with a central tenectomy to treat large-angle horizontal strabismus.

PURPOSE: To report the effectiveness of incorporating a central tenectomy on the recessed rectus muscles when treating large-angle horizontal deviations.

METHODS: Patients undergoing recession and central tenectomy from March 2010 to January 2013 were prospectively enrolled. The procedure entails making two longitudinal incisions, each 4 mm, on the muscle adjacent to sutures made during the recession procedure. With recession complete and muscle sutured to the sclera, the central flap (with approximately one-third of the insertion width) is excised. The following variables were analyzed: expected correction (according to surgical dose tables), achieved correction (preoperative deviation minus postoperative deviation), and tenectomy effect (achieved correction minus expected correction).

RESULTS: A total of 16 horizontal rectus muscles of 16 eyes of 12 patients were included, 8 with exotropia and 4 with esotropia. No cases of significant limitation in duction in the field of the recessed muscle occurred. In all patients, the median achieved corrections at distance (55(Δ)) and at near (53.5(Δ)) were significantly higher than the median expected corrections (45(Δ) for both distance and near [P = 0.002]). The postoperative deviations at distance and near were lower in the unilateral surgery group (n = 8; statistically significant only for near deviation). The tenectomy effects in the esotropia group for both distance and near were more pronounced than those of the exotropia group (although not statistically significant).

CONCLUSIONS: In our patients central tenectomy of the recessed rectus muscles increased the effect of recession procedures without limiting ductions. There were possible greater effects in esotropia patients and recession-resection procedures.