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Purpose
To analyze epidemiology, clinical features, and surgical outcomes of type III acute acquired concomitant esotropia (Bielschowsky esotropia (BE)).
Methods
The medical charts of patients diagnosed with acquired concomitant esotropia between 2013 and 2021 were reviewed. Assessed data were age, gender, age at diplopia onset, age at the diagnosis, refraction, visual acuity, neuroimaging, diplopia onset, angle of deviation, stereopsis, surgical procedure, amount of surgery, and relapse of diplopia after surgery. Moreover, we investigated the correlation between the use of electronic devices and the onset of diplopia.
Results
One hundred seventeen patients (mean age 35.07 ± 15.81 years) were included in the study. The mean delay to the diagnosis was 3.29 ± 3.62 years. Myopia range was 0 to 17 diopters spherical equivalent. 66,3% spent more than 4 hours a day using laptops, tablets, or smartphones at the onset of diplopia, and 90,6% presented a subacute onset. None showed neurologic signs or symptoms. Patients who underwent surgery were ninety-three, with a rate of surgical success of 93.6%, and a relapse rate of 17.2%. A negative correlation resulted between pre-operative deviation and age at diagnosis (ρ = -0.261; p<0.05), whereas factors associated with surgical failure were older age at diplopia onset (p = 0.042) and longer delay between onset and diagnosis (p = 0.002).
Conclusion
We registered an outstanding increase in prevalence of BE, which could be related to the exponential increase in the use of electronic devices for professional, educational, and recreational purposes. A prompt diagnosis and an augmented dose of surgery allows good motor and sensory results.