Cavernous Angioma Originating Directly from the Oculomotor Nerve: To Treat or Not to Treat?

Cavernous angiomas (CA) affecting cranial nerves (CN) are exceptionally rare. Most reported cases involve the optic nerves, with even fewer occurrences in other CN. In this report, the authors describe a case of an extra-axial CA affecting the oculomotor nerve, which was managed conservatively. The authors also review the outcomes of other therapeutic options based on cases documented in the existing literature. Case report: 36-year-old woman presented to the Emergency Department with a headache in the left temporal region, predominantly at night, along with mild left palpebral ptosis and binocular diplopia of 2 months duration. Brain MRI revealed a lesion exhibiting typical characteristics of CA in the left lateral region of the interpeduncular cistern, in close contact with the left oculomotor nerve. After considering treatment options and in consultation with the patient, a conservative management plan with periodic MRI follow-up was chosen. After 2 years of follow-up, the patient showed favorable progress. Although exceptional, CA should be considered in the differential diagnosis of other more common extra-axial lesions involving CN. The therapeutic management of a CA of the oculomotor nerve remains controversial due to the limited number of cases described in the literature. The authors suggest that for individuals with asymptomatic or mildly symptomatic CA affecting the oculomotor nerve, a conservative treatment approach is the most suitable choice to preserve neurological function. In cases characterized by progressive symptoms, a history of recurrent bleeding, or evidence of lesion enlargement on sequential imaging assessments, total microsurgical resection should be considered.