Comparison of botulinum toxin with surgery for the treatment of acute acquired comitant esotropia and its clinical characteristics

We compared the therapeutic effects between botulinum toxin and surgery for acute acquired comitant esotropia (AACE) and analyze its clinical characteristics. The data of the 29 cases, who received treatment for AACE in the Ophthalmic Center of the First Affiliated Hospital of Zhengzhou University and Henan Provincial Ophthalmology Hospital between January 2016 and January 2017, were collected. The 29 cases with AACE were followed for 6 months or more, and received either botulinum toxin injection (group A with 13 cases) or squint correction (group B with 16 cases). The distant and near deviation angles were compared between the two groups before and after treatment. The success rate (total horizontal deviation of 10 prism diopters or less) and stereopsis were compared between the two groups at post-treatment 6 months. At the same time, the relations between distant and near deviation angles were analyzed among different myopia levels and different AACE types. Results indicated that he success rate was not significantly different at post-treatment 6 months (84.6% vs 81.3%, P = 1.00). The distant and near deviation angles were all significantly different one day and one month after treatment (all P < 0.05); but at post-treatment 6 months, they were not significantly different (all P > 0.05) between the two groups. There were no significant differences in the distant and near stereoacuity between the two groups at post-treatment 6 months (all P > 0.05). Among the 25 cases with myopia, the pre-treatment distant deviation angle was significantly higher than pre-treatment near deviation angle in the cases with myopia level >−2.5 D (P < 0.05), and the pre-treatment distant and near deviation angles were all significantly higher in the cases with type-IIAACE than in the cases with type-IIIAACE (all P < 0.05). This study suggests that Botulinum toxin is as effective as surgery in the treatment of AACE at post-treatment 6 months. For the cases with myopia level >−2.5 D, the pre-treatment distant deviation angle is significantly higher than pre-treatment near deviation angle; and both pre-treatment distant and near deviation angles are greater in the cases with type-IIAACE than in the cases with type-IIIAACE.