Comparison of lateral rectus muscle re-recession and medial rectus muscle resection for treatment of postoperative exotropia

Surgical success of lateral rectus resection for residual and recurrent esotropia

PURPOSE

To assess the surgical outcomes of reoperations for residual and recurrent esotropia.

METHODS

A retrospective chart review of all patients who underwent surgery during 2000-2017 at a tertiary referral medical center for recurrent or residual esotropia was conducted. Patients who underwent bilateral medial rectus recession as primary surgery and lateral rectus resection as second surgery were included. The success rate of second surgery and its association to various factors were examined. Success of reoperation was defined as mean deviation of < 10 prism diopters (= PD) at last follow-up.

RESULTS

Twenty-seven patients with mean post-operative follow-up of 50.4 ± 31.7 months were included. On last follow-up examination, 15 (55.6%) patients had a successful reoperation and 12 (44.4%) patients had unsuccessful reoperation. The two groups were similar in the pre-operative amount of esotropia for distance and near. On last follow-up examination, the amount of mean deviation was 1.9 PD esotropia (8 PD exotropia to 9 PD esotropia) in the success group and 11.2 PD esotropia (22.5 PD exotropia to 35 PD esotropia) in the failure group. In the failure group, 75.0% of patients were under-corrected (esotropia of ≥ 10 PD) on last follow-up examination.

CONCLUSION

Strabismus reoperation in cases of residual or recurrent esotropia was successful in slightly more than half of the patients. Surgical failure was more commonly associated with undercorrection and less with overcorrection.

Bilateral Lateral Rectus Recession for the Treatment of Recurrent Exotropia after Bilateral Medial Rectus Resection

PURPOSE

To evaluate the efficacy of bilateral lateral rectus muscle recession (BLR) to treat recurrent exotropia after bilateral medial rectus muscle resection (BMR).

METHODS

Twenty-four patients who underwent BLR for recurrent exotropia and were followed up for more than 6 months were included in this retrospective study. All of them had prior BMR. The angle of deviation, success rates, near stereopsis, and surgical effect of BLR were evaluated. Surgical success was defined as postoperative deviations ≤10 prism diopters (PD).

RESULTS

The overall mean follow-up time after reoperation for patients was 24.13 ± 15.01 months (range 6-60 months). The mean angle of deviation at distance was significantly reduced from -37.75 ± 14.93 PD to +1.50 ± 6.43 PD (p < 0.001). Twenty-two (91.6%) of 24 patients had successful outcomes, 1 (4.2%) had overcorrection, and 1 (4.2%) had undercorrection at the last follow-up. Improved stereopsis after reoperation was observed in 78.3% (18/23) of the patients. The mean surgical effect was 2.78 ± 0.71 PD/mm.

CONCLUSION

Based on our results, BLR could be an effective and safe method for treating recurrent exotropia after a moderate to large amount of BMR.

Outcomes of bilateral lateral rectus recession in treatment of recurrent exotropia after bilateral medial rectus resection

PURPOSE

To report the results of bilateral lateral rectus muscle recession for recurrent exotropia in cases where the primary surgery was a bilateral medial rectus resection.

METHODS

Retrospective chart review of 15 subjects who completed 6 months of follow-up. Data collected included patients' demographics and pre- and post-operative measurements of ocular alignment and motility. Surgical nomogram used was the same nomogram we use for primary cases of exotropia.

RESULTS

At 6-month follow-up, 73.3% of cases had a successful surgical outcome (defined as 8 PD of esotropia to 10 PD of exotropia). In addition, recession of lateral rectus muscles against the previously resected medial recti did not result in a significant increase in the limitation of abduction.

CONCLUSION

Bilateral lateral rectus recession using standard surgical tables is a safe and effective method for treating recurrent exotropia following bilateral medial rectus resection. Even large primary resections up to 12 mm do not seem to affect the results of bilateral lateral rectus recession.

Early postoperative overcorrection in recurrent exotropia

OBJECTIVE

To investigate the surgical outcome according to the angle of deviation at postoperative day 1 in patients with recurrent exotropia DESIGN: Retrospective case series METHODS: Surgical outcome in patients with recurrent exotropia for at least 1 year was analyzed retrospectively. Patients were divided into 3 subgroups according to the angle of deviation at postoperative day 1: overcorrection group (≥2 prism diopter [PD] of esodeviation), orthotropic group (orthotropia or <5 PD of exodeviation), and undercorrection group (≥5 PD of exodeviation). Success was defined as ≤5 PD of esodeviation or ≤10 PD of exodeviation at the final visit.

RESULTS

One hundred and six patients were included in this study. Age at surgery was 11.8 ± 6.9 years, and preoperative angle of deviation was 22.9 ± 6.3 PD at distant. Patients were followed-up for 24.4 ± 12.8 months. There were 20 (18.9%), 82 (77.4%), and 4 (3.8%) patients in overcorrection, orthotropic, and undercorrection groups at postoperative day 1 (p = 0.001). The surgical success rate at the final visit in the overcorrection group (95%) was higher than that in orthotropic and undercorrection groups (76.8% and 25%, respectively, p = 0.004). In univariate regression analysis, overcorrection at postoperative day 1 was the only reliable factor for long-term success (odds ratio [OR] = 24.101, p = 0.01).

CONCLUSION

Overcorrection at postoperative day 1 is a good surgical predictor of successful outcome in surgery for recurrent exotropia.

A chronicle of surgical thinking and doing for exotropia: innovations and rediscoveries

PURPOSE

To review the evolution of theories and practices concerning surgery for exotropia over the last approximately 200 years.

METHODS

Major ophthalmology texts and relevant references were reviewed to discover experience and thinking concerning the causes of comitant intermittent and constant exotropia and corrective surgical approaches.

RESULTS

The concept that excessive divergence is the cause of comitant exotropia has given way to one recognizing that this disorder is a position of rest modified by convergence. Some operations discarded as unreliable or dangerous remain so today. Others continue to be well accepted, whether or not relating to advances in understanding of this condition. Several procedures practiced at former times have regained popularity.

CONCLUSIONS

Concern for the characteristics of extraocular muscle structure and function has led to surgical thinking that goes beyond consideration only of direction and magnitude of deviation. Sophisticated devices now provide heretofore unavailable information consistent with this new approach. The history of progress in surgery for exotropia is mixed. Although some procedures now employed are new, others currently in favor had been well known and formerly utilized by ophthalmologists for many decades. These should be regarded as rediscoveries or revivals rather than as novel. This review also suggests a need to address how to better report retrospective studies.