Botulinum Toxin Injection versus Extraocular Muscle Surgery for Acute Acquired Comitant Esotropia

Abstract

Purpose

To compare the success rate of extraocular muscle surgery and botulinum toxin injection for treatment in patients with acute acquired comitant esotropia (AACE).

Patients and Methods

This is a retrospective cohort study in which we treated 34 patients of AACE with botulinum toxin compared with 80 patients who had been treated with surgery. The data included angle of deviation in prism diopter (PD) at baseline and one, three, and six months after treatment. The main outcome was the success rate in each treatment group.

Results

In the surgery group, mean esodeviation angles at baseline and one, three, and six months after treatment were 50.8 ± 18.3 PD, 4.9 ± 8.3 PD, 4.6 ± 9.5 PD, and 5.5 ± 10.3 PD, whereas those in the botulinum toxin group were 51.2 ± 14.3 PD, 13.9 ± 17.4 PD, 22.0 ± 19.3, and 31.3 ± 23.8 PD, respectively. There was a statistically significant difference in the deviation angles between the two groups (p < 0.001). The success rate in the surgery group at one, three, and six months was 81%, 84%, and 79%, whereas that in the botulinum toxin group was 50%, 27%, and 27%.

Conclusion

Botulinum toxin injection was not as effective as conventional extraocular muscle surgery in AACE patients. However, the treatment is safe, fast-acting, and improves both cosmetic appearance and quality of life. This may be considered as a chance for patients not preferring surgery.

Keywords:

• botulinum toxin
• muscle surgery
• acute acquired comitant esotropia

Acknowledgments

The authors thank Dr. Kaewjai Thepsuthammarat, Clinical Epidemiology Unit, Faculty of Medicine, Khon Kaen University for statistical analysis, and Dr. Dylan Southard for assistance with the English-language presentation of the manuscript, via the KKU Publication Clinic (Thailand). This study was supported by a research grant (IN 62339) from the Khon Kaen University Faculty of Medicine.

Disclosure

The authors report no conflicts of interest in this work.