Acquired non-accommodative comitant esotropia (ANAET) is increasingly recognized as a significant condition primarily affecting older children and adults. Recent research from the Department of Ophthalmology at Seoul National University Bundang Hospital reveals promising long-term efficacy of botulinum toxin A (BTX) injections to treat this disorder.
ESOPHORIA, characterized by inward turning of one or both eyes, can lead to various complications including double vision, especially when uncontrolled. Treatment traditionally revolves around surgical intervention, yet this recent study focuses on whether BTX—a neurotoxin renowned for its application across diverse medical fields—could serve as a viable, less invasive alternative.
Data from patients treated between 2010 and 2022 was examined, encompassing 42 individuals with diagnosed ANAET having initial angles of esodeviation of ≤ 25 prism diopters (PD). The database included patient records detailing angles of esodeviation before injection, post-treatment ocular alignment assessed at various intervals, and documented complications.
The results show treatment success rates significantly favoring BTX injections: 90.5% at the six-month mark, tapering to 76.2% at one year, and remaining stable at 73.8% through the final assessments. These figures indicate enduring alignment without immediate invasive procedures. By gathering this data, researchers aimed to identify factors influencing success rates.
Notably, the analysis highlighted the baseline angle of esodeviation as the single most significant predictor of success. Specifically, those with angles of ≤ 15 PD before treatment exhibited markedly higher success rates compared to those with larger deviations—88% success versus 52.9% respectively. This finding prompts clinicians to recommend BTX injections as first-line treatment for patients whose maximum angle of esodeviation stands at or below this threshold.
While surgical intervention may advance as the gold standard for acute cases, the study attributed advantages to BTX therapy including reduced recovery time and lower costs, making it appealing especially for patients seeking non-surgical solutions. Yet, the authors also caution against potential downsides of BTX injections—such as transient ptosis and muscle atrophy, emphasizing continued monitoring post-injection.
Interestingly, evidence points to modern lifestyle habits as contributing factors to the rising incidence of ANAET. A history of extensive near-vision tasks, particularly with smartphone usage prevalent among younger generations, correlates with the condition's onset. Ocular muscle imbalances present unique challenges, but BTX offers hope as part of the therapeutic arsenal against this increasingly common esotropic condition.
Further research and refinement of treatment protocols including precise dosage guidelines are necessary to maximize therapeutic outcomes. The authors of the research conclude, "BTX injection can be a highly favorable therapeutic option for ANAET patients," underscoring the need to holistically evaluate long-term options available. This work sets the foundation for future investigations as more patients seek less invasive alternatives to conventional surgical procedures.