THE BLOOD-SUPPLY OF THE TRIGEMINAL NERVE ROOT, WITH SPECIAL REFERENCETO THE TRIGEMINOCEREBELLAR ARTERY

THE VASCULATURE OF the 29 roots of the trigeminal nerve was examined a fter india ink and gelatin had been injected into the vertebrobasilar arterial system. The trigeminal arteries were most often noted to aris e from the superolateral pontine branch of the basilar artery (89.66%) , and from the peduncular cerebellar branch of the anterior inferior c erebellar artery (75.86%). The trigeminocerebellar artery supplied two roots (6.89%) of the trigeminal nerves. The number of trigeminal arte ries ranged from two to six, and their diameters ranged from 100 to 51 0 mu m. Anastomoses among them were seen in 37.93% of the cases. The a rteries formed the vascular rings around 58.61% of the roots. The moto r portion of the trigeminal nerve most often received blood from the s uperolateral pontine artery (79.31%). The same artery most commonly su pplied the rostral part of the sensory portion, which corresponded to the ophthalmic division of the trigeminal nerve. The superolateral art ery, together with the inferolateral pontine artery and the peduncular cerebellar branch of the anterior inferior cerebellar artery, irrigat ed the middle part of the sensory portion, which corresponded to the m axillary division. The caudal part of that portion, which corresponded to the mandibular division, was commonly perfused by the peduncular c erebellar branch of the anterior inferior cerebellar artery. In this a rticle, we discuss the possible clinical significance of the anatomic data observed.