Long-term Outcomes After Same Amount of Bilateral Rectus Muscle Recession for Intermittent Exotropia With the Same Angle of Deviation

Longitudinal Rehabilitation of Binocular Function in Adolescent Intermittent Exotropia After Successful Corrective Surgery

PURPOSE

To study the longitudinal rehabilitation of binocular visual function in adolescent intermittent exotropia (IXT) after successful surgery and compare the results with those of a normal population. The role of binocular function in ocular alignment stability was also evaluated postoperatively.

METHODS

In this prospective study, 30 adolescents with IXT successfully corrected after 1 month were followed for 12 months, and 30 children with normal vision were enrolled as controls. Stereopsis, the fusional vergence amplitude, sensory fusion, and accommodative flexibility were measured to assess binocular function at baseline and 6 and 12 months postoperatively. The controls were tested once when they were enrolled in the study.

RESULTS

The deviation was -32.00 ± 8.60 prism diopters (PD) at distance fixation and -36.0 ± 9.10 PD at near fixation preoperatively with an average correction of 28.53 ± 3.79 PD and 30.67 ± 1.34 PD at 1 month postoperatively. Distance stereoacuity and near stereoacuity improved from 1 to 12 months postoperatively (p = 0.025 and p = 0.041, respectively). Compared with the controls, the fusional convergence reserve at distance (p = 0.025) and near (p = 0.033) fixations and fusion reserve ratio at distance (p = 0.000) and near (p = 0.000) fixations remained subnormal, whereas sensory fusion (p = 0.237), distance stereopsis (p = 0.120), and the fusional divergence amplitude at a distance (p = 0.168) were normal. However, no significant correlations were found between binocular functions at 1 month postoperatively and the postoperative drift.

CONCLUSION

Binocular function significantly improved from before to after successful corrective surgery and continued to improve from 1 to 12 months postoperatively in adolescents with IXT. No significant correlations were found between binocular functions at 1 month postoperatively and ocular alignment stability.

Long-term Motor and Sensory Outcomes After Unilateral Lateral Rectus Recession-Medial Rectus Resection for Basic Intermittent Exotropia

PURPOSE

To report long-term motor and sensory outcomes after unilateral lateral rectus recession-medial rectus resection for basic intermittent exotropia.

METHODS

The medical records of patients who had undergone unilateral lateral rectus recession-medial rectus resection for basic intermittent exotropia and were observed postoperatively for a minimum of 10 years were reviewed retrospectively.

RESULTS

A total of 41 patients were included (mean age: 6.07 ± 2.96 years; range: 3 to 17 years). The mean postoperative follow-up was 13.28 ± 3.27 years (range: 10 to 23 years). Overall, 19 patients (46%) had surgical success at their most recent follow-up visit. Age at onset of strabismus, age at surgery, strabismus duration, preoperative size of near and distance deviation, presence of stereopsis, and initial postoperative overcorrection did not predict motor outcome after surgery. Twenty-five patients (74%) achieved stereopsis. None of the 4 patients without binocular single vision preoperatively achieved stereopsis, compared to 3 of 7 patients (43%) with peripheral binocular single vision (P = .02). Five of 7 patients (71%) with a preoperative stereoacuity of 120 to 240 seconds of arc improved to 60 seconds of arc. Age at surgery did not predict stereopsis. Patients with a strabismus duration of 5 years or less achieved a better stereopsis.

CONCLUSIONS

Fewer than half of the patients with basic intermittent exotropia achieved a successful long-term surgical outcome. Age at surgery, strabismus duration, preoperative stereopsis, and an initial postoperative overcorrection did not predict motor outcome. A pre-operative absence of binocular single vision indicated a poor prognosis for stereopsis. A shorter duration of strabismus predicted a better stereopsis after surgery. [J Pediatr Ophthalmol Strabismus. 2020;57(5):326-332.].

Lateral rectus advancement versus medial rectus recession for consecutive esotropia

PURPOSE

To compare lateral rectus advancement with medial rectus recession for patients with consecutive esotropia without abduction limitation.

METHODS

Forty-three patients who developed consecutive esotropia following bilateral lateral rectus recession for intermittent exotropia were reviewed retrospectively. Twenty-two patients underwent lateral rectus advancement (lateral rectus advancement group) and medial rectus recession was performed in 21 patients (medial rectus recession group). Success rate of the surgery was based on the percentage of postoperative esophoria or exophoria of less than 8 PD, which did not require a third surgery. Mean follow-up after second surgery was 23.5 ± 8.7 months.

RESULTS

Mean consecutive esotropia in the lateral rectus advancement group was 24.8 ± 9.0 PD. Eight patients were orthophoric after second surgery; mean postoperative esophoria and exophoria/tropia was 5.4 ± 3.4 PD and 6.5 ± 5 PD, respectively. Postoperative success rate in this group was 90.9%. Mean consecutive esotropia in the medial rectus recession group was 21 ± 98.4 PD. Three patients were orthophoric after second surgery; mean postoperative esotropia/phoria and exophoria was 9.5 ± 5.0 PD and 5.2 ± 1.3 PD, respectively. Postoperative success rate in this group was 71.4%. Postoperative undercorrection rate of 4.5% in lateral rectus advancement group was significantly less than the similar measure of 28.6% in medial rectus recession group (chi-square, P = 0.03).

CONCLUSION

Advancement of the previously recessed lateral rectus has improved consecutive esotropia better than medial rectus recession.