Abstract
Purpose :
To evaluate short-and long-term motor outcomes of single unilateral medial rectus muscle recession for esotropia.
Methods :
A retrospective review of 96 consecutive patients (aged 3-month to 12.7-year) with esotropia without vertical deviation or cranial nerve palsy treated with graded unilateral medial rectus recession surgery (up to 10.5mm). Alignment was measured at 1 month and a minimal of 2 years after surgery. Criteria for successful motor outcome include alignment ±10Δ from orthophoria. Outcome evaluation was a comparison of successful alignment versus overcorrection or undercorrection at 1 month postoperatively as well as on the final examination. Dose responses were evaluated for small angle esotropia (≤30Δ at 33cm) and large angle esotropia (>30 Δ at 33cm). The achievement of target alignment for patients with amblyopia and retinopathy of prematurity (ROP) was analyzed.
Results :
The mean preoperative deviation was 30.9 Δ (±10.8 Δ, range 10Δ to 70Δ) and mean follow-up time was 4.75 years. The mean age of diagnosis was 2.6 years. There was a statistically significant difference between the rate of early vs. late successful correction (56.3% vs. 65.6%, p=0.040), early vs. late undercorrection (43.8% vs. 30.2%, p=0.006) and early vs. late overcorrection (0% vs. 4.2%, p=0). The mean response to surgery was 2.9 Δ per mm of medial rectus muscle recessed and was moderately and positively related to the preoperative angle of deviation (R=0.53, p<0.05). For small angle esotropia, the mean response to surgery was 2.5Δ per mm of medial rectus muscle recessed and was positively related to the preoperative angle of deviation (R=0.42, p=0.001). For larger angle esotropia, the mean response to surgery was 3.5Δ per mm of medial rectus muscle recessed and was moderately and positively related to the preoperative angle of deviation (R=0.52, p=0.0006). Off-target correction is associated with neither preoperative amblyopia (odds ratio 0.56, 95% CI [0.17, 1.75], p=0.32) nor ROP (odds ratio 0.95, 95% CI [0.25, 3.6], p=0.94).
Conclusions :
The dose effect of unilateral medial rectus recession procedure for correction of esotropia is related to the degree of preoperative esotropia, with very low rate of overcorrection. The postoperative alignment at 1 month is predicative of long-term alignment. Preoperative amblyopia and ROP are not associated with off-target alignment with unilateral medial rectus recession.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.