Direct Carotid Cavernous Fistula Due to Rupture of a Cavernous Carotid Aneurysm Embedded within a Prolactinoma after Cabergoline Administration.

BACKGROUND

A small number of reports have discussed subarachnoid hemorrhage from a ruptured aneurysm embedded within a prolactinoma. To the best of our knowledge, however, no reports have discussed an embedded carotid cavernous fistula (CCF). We report a patient with CCF secondary to a ruptured internal carotid artery (ICA) aneurysm embedded within a prolactinoma.

METHODS

A 61-year-old woman was referred to our hospital with sudden headache, vomiting, and dizziness. Magnetic resonance imaging revealed a small acute subdural hematoma, recurrent prolactinoma, and left cavernous carotid aneurysm. Conservative therapy was initiated. Her serum prolactin level at hospitalization was 11 300 μg/L; therefore, we initiated cabergoline therapy. Twenty days after cabergoline administration, she suddenly presented with left conjunctival injection and pulsatile tinnitus. Angiography revealed a left direct CCF with a connection between the cavernous ICA and the cavernous sinus via the aneurysm, and venous congestion. To prevent hemorrhagic stroke, we scheduled staged surgery. First, we urgently performed embolization of the cavernous sinus and fistula. One month later, to prevent aneurysm re-rupture, we performed a radical operation with superficial temporal artery-middle cerebral artery double anastomosis with proximal occlusion of the left ICA at the cervical portion. The patient was discharged 2 weeks after surgery without neurological deficits. Follow-up angiography revealed complete occlusion of the aneurysm 2 months postoperatively.

CONCLUSIONS

An aneurysm embedded within a prolactinoma, as in our patient, should be closely observed when cabergoline administration is started.