This is a single-center, prospective, randomized controlled trial evaluating type A botulinum toxin injection and prism therapy for the treatment of small-angle acute acquired concomitant esotropia.
Specific Aim 1 (Primary): To compare the reduction of deviation angle and improvement of diplopia symptoms between botulinum toxin injection and prism therapy for the treatment of small-angle acute acquired concomitant esotropia.
Specific Aim 2 (Secondary): To compare the improvement of visual functions between botulinum toxin injection and prism therapy for the treatment of small-angle acute acquired concomitant esotropia.
acute acquired concomitant esotropia diagnosis (sudden onset of esotropia or diplopia, no significant change in the degree of strabismus in each eye position, and no limitation in eye movement)
strabismus angle ≤ 25PD
best corrected visual acuity of both eyes ≥ 1.0
intracranial disease is excluded by cranial CT or magnetic resonance imaging
reduction of strabismus angle by more than 10 prism diopters after refractive correction
history of other ocular diseases or ocular surgeries
presence of organic brain lesions or systemic diseases