Severe unilateral abducens nerve palsy from cavernous sinus carotid vascular ectasia.

PURPOSE: Carotid cavernous sinus ectasia is a rare cause of abducens nerve palsy.

OBSERVATION: We present a case of severe unilateral progressive esotropia resulting from cavernous sinus carotid vascular ectasia in a 67 y/o female. She had progressive esotropia over the years with no neuroimaging despite having regular ophthalmic care. Magnetic resonance imaging determined the etiology of her chronic severe esotropia.

CONCLUSION AND IMPORTANCE: Carotid cavernous sinus ectasia should be considered in the differential of severe progressive unilateral abducens nerve palsy. Magnetic resonance imaging with magnetic resonance angiography is important to determine etiology of severe progressive esotropia.