Pre- and Postoperative MRIs of a Case of Esotropia With an Accessory Extraocular Muscle.

Accessory extraocular muscles are rare abnormal structures that attach to the posterior globe, resulting in atypical limitations of eye movement and enophthalmos. We present herein the case of a 12-year-old girl with severe esotropia and restricted abduction in the right eye, who was found to have an accessory extraocular muscle on MRI. The patient underwent a successful surgery, and a comparison of pre- and postoperative MRIs showed improvement in the right eye's position and release of the abnormal structure in the orbit. To the best of our knowledge, this is the first reported case comparing pre- and postoperative MRI findings of an accessory extraocular muscle.