Medial rectus fadenoperation for esotropia only at near fixation

The patient with a large esodeviation at near and a minimal if any deviation at distance who is unable to discontinue bifocal wear or demonstrates a decrease in binocular function presents a difficult therapeutic dilemma to the strabismologist. The medial rectus fadenoperation has been proposed as a method of reducing the accommodative convergence/accommodation (AC/A) ratio and may be a reasonable approach to correct a deviation that is present only at near fixation. We examined our results with this type of operation in these difficult patients.

A review of consecutive patients who underwent a bilateral medial rectus fadenoperation (no recession) for high AC/A ratio esotropia with a significant esodeviation only at near was performed. Preoperative and postoperative motility and sensory status were evaluated.

Sixteen patients meeting the criteria were identified. The preoperative mean distance deviation was 8.8 PD of esodeviation and the mean near deviation was 33 PD of esodeviation. The mean AC/A ratio (by the gradient method) preoperatively was 7.4 PD/D. The average age at surgery was 8 years. Six (38%) had undergone prior strabismus surgery. Average follow-up was 36 months (range 12 to 98 months). Postoperatively the mean distance deviation was 3.2 PD of esodeviation and the mean near deviation was 10.3 PD of esodeviation. The mean decrease in the near deviation was 22.8 PD. The mean postoperative AC/A ratio was 2.9. Ninety-five percent of the patients normalized their AC/A ratios and 70% attained 400 arc-sec of stereopsis postoperatively (vs 44% preoperatively. The majority of patients (86%) were able to maintain satisfactory near ocular alignment without bifocals.

The fadenoperation appears to be useful in this patient population by reducing the distance-near disparity and the AC/A ratio, by decreasing the necessity for bifocal wear, and by improving binocular function at near.