Convergent strabismus fixus after bilateral abducens nerve palsies due to aneurysms

Abstract

Rationale:Convergent strabismus fixus is an ocular motor abnormality in which the eye is fixed in adduction. This condition is mostly associated with high myopia and is caused by a displacement of the extraocular muscles. We report a nonmyopic woman with convergent strabismus fixus due to aneurysms.Patient concerns:A 79-year-old woman complained of progressive worsening of esotropia about 50 years prior to her visit. Neuroimaging showed that the eye was not dislocated, and the extraocular muscles were not displaced. However, aneurysms were found bilaterally from the intracavernous carotid arteries and the location was on both abducens nerves.Diagnoses:Chronic bilateral abducens nerve palsies due to aneurysms.Interventions:Endovascular treatment was successfully performed for the aneurysms.Outcomes:Convergent strabismus fixus still remained.Lessons:Chronic abducens nerve palsies may develop to nonmyopic convergent strabismus fixus without displacement of extraocular muscles, and mass lesions in the brain including aneurysms should be ruled out when orbital MRI cannot explain the condition.