Evaluation of Efficacy and Lateral Gaze Incomitance in Symmetrical and Asymmetrical Surgery for Concomitant Esotropia and Exotropia

Abstract

Purpose

Evaluation of asymmetrical and symmetrical horizontal strabismus surgery as regards efficacy and postoperative lateral gaze incomitance.

Patients and Methods

This prospective comparative interventional case series study included 40 patients of age more than 3 years with alternating horizontal strabismus. Patients were divided according to the type of horizontal deviation into esotropia and exotropia groups, which were further subdivided into asymmetrical and symmetrical subgroups in each type. The surgery was defined as symmetrical procedure if the surgery was done on the same muscle in the two eyes and it was defined as asymmetric in recess-resect procedures in one eye, and three horizontal muscles surgery. Preoperative and postoperative measurements were done in primary position, right, and left gaze using alternate prism cover test and hand-held orthopedic goniometer.

Results

At the end of follow-up period, a statistically insignificant difference (P value = 0.8057) was present in the success rate between the asymmetrical and symmetrical subgroups of esotropia (90 and 86.67%, respectively) and it was 100% in both exotropia subgroups. Lateral gaze incomitance results were different between esotropia and exotropia subgroups. In esotropia, a statistically significant difference was reported at 1 month (0.009), which became insignificant at 6 months (0.077) and 12 months (0.077) between asymmetrical and symmetrical subgroups. In exotropia subgroups, there was a statistically insignificant difference in lateral gaze incomitance at 1, 6, and 12 months (P = 1).

Conclusion

Asymmetrical procedure had the same efficacy and success rate of symmetrical procedure for the correction of concomitant horizontal deviations in primary gaze without persistent postoperative lateral gaze incomitance, especially in exotropia.

Clinical Trial Registration

NCT04199286.

Keywords:

• asymmetrical
• symmetrical
• esotropia
• exotropia
• horizontal strabismus
• lateral incomitance

Ethics

Approval was obtained from the Research Ethics Committee of Faculty of Medicine, Minia University (NO: 69-7/2018). All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed written consent was obtained from all patients or their legal guardians included in the study.

Acknowledgment

This paper was uploaded to the Minia University, University repository as a Master thesis in 2019.²⁶

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agreed to be accountable for all aspects of the work.

Disclosure

The authors reported no conflicts of interest in this work.

Additional information

Funding

No financial support was received for this submission.