Introduction: Persistent stapedial artery (PSA) is an abnormal small vessel that arises from the
petrous portion of the internal carotid artery due to failure of the regression of
the embryonic stapedial artery. The embryonic stapedial artery anastomoses with the
ventral pharyngeal artery, which is a precursor of the external carotid artery and
supplies the middle meningeal artery (MMA). The regression of the stapedial artery
results in the formation of the caroticotympanic artery. Failure of this regression
can result in abnormal anastomosis between the basilar artery and the middle meningeal
artery. We present an angiographic image that demonstrates this rare anatomic variant.
Case Presentation: A cerebral angiogram of a 33-year-old male demonstrated the presence of a right-sided
persistent stapedial artery with direct communication between the right middle meningeal
and basilar arteries ([Figs. 1] and [2]).
Conclusion: Direct communication between the middle meningeal and basilar arteries is rare. Two
theories exist regarding the development of such connections: the anastomosis between
the basilar remnant of the trigeminal artery and the PSA; and the presence of a lateral
pontine artery that develops during the embryologic life and anastomoses with the
PSA. The recognition of rare anatomical variants is crucial to avoid the unintended
consequences of endovascular interventions. Failure to recognize the persistent stapedial
artery can result in nontarget embolization of the brainstem with devastating consequences.
Fig. 1
Fig. 2
