Medial Rectus Fenestration Technique Reduces Angle of Deviation in Esotropia

Using a medial rectus muscle fenestration technique to treat partially accommodative esotropia in pediatric patients is effective at reducing the angle of deviation, according to a study published in the Journal of American Association for Pediatric Ophthalmology and Strabismus (AAPOS). 

The prospective noncontrolled study enrolled 61 children ≤10 years of age with partially accommodative esotropia of 10Δ-35Δ and no high ratio of accommodative convergence to accommodation (AC/A). They underwent surgery from February 2018 to August 2019, with success defined as alignment within 8Δ of orthotropia at final follow-up. The technique is performed using “two splitting incisions … made by blunt dissection parallel to the muscle fibers on the superior and inferior borders of the medial rectus muscle, leaving a thin strip of muscle fibers on each edge. The wide, central part of the muscle is excised from its insertion to a point 5 mm to 8 mm from the insertion, depending on the angle of the esotropia.” Sutures are not used. 

Researchers found that the surgery was well-tolerated and reduced the angle of esotropia for distance from 22.20Δ ± 4.22Δ to 2.72Δ ± 4.71Δ (P < 0.001), and did not cause incomitance or distance–near disparity. In 88% of cases at 3 to 6 months follow-up, satisfactory horizontal alignment defined as alignment within 8Δ of orthotropia at distance was achieved. No overcorrections occurred.

The study did have limitations, including its relatively small cohort size, maximum follow-up of 1 year, lack of a control arm, and its use only in children who had a AC/A ratio and only on the medial rectus muscle.

“Despite these limitations, fenestration technique has clear advantages over conventional recession or hang-back recession: the procedure is relatively easy, and it is entirely sutureless, which reduces the risk of scleral perforation to almost zero,” according to the researchers. “Our success with this procedure is comparable to that with nonabsorbable suture hang-back recession. High-resolution functional magnetic resonance imaging in a future study may provide better understanding of the mechanism of action of this fenestration procedure.”

This research was previously presented at the 46th Annual Meeting of the AAPOS, April 9-11, 2021.

Reference

Elkhawaga M, Kassem A, Helaly H, El Shakankiri N, Elkamshoushy A. Treatment of partially accommodative esotropia in children using a medial rectus muscle fenestration technique. J AAPOS. 2021:S1091-8531(21)00648-0. doi:10.1016/j.jaapos.2021.08.306