Persistent trigeminal artery: A unique anatomic specimen-analysis and therapeutic implications

OBJECTIVE: Persistent primitive carotid-basilar artery anastomoses are unco mmon, and are usually seen on an angiogram or discovered at autopsy. The mo st frequent type of anastomosis is the persistent trigeminal artery. METHODS: A single case of a medial variation of the persistent trigeminal a rtery, as seen in a well-preserved human adult anatomic specimen injected w ith red latex, is presented, and the anatomy of this uncommon anastomosis i s discussed. RESULTS: This specimen is unique in its clear preservation of the artery, w hich arises from the medial portion of the right intracavernous carotid art ery and gives rise to two branches, the inferior hypophyseal artery and the dorsal meningeal artery to the clivus. CONCLUSION: A new variation of the persistent trigeminal artery is describe d, which is important to support the possibility that move than one variety of carotid-basilar anastomosis exists in this region.