P1 segment
peduncular segment(P1)
● mesencephalic perforating aa. (⇒ tectum, cerebral peduncles, and these nuclei: Edinger- Westphal, oculomotor and trochlear)
● interpeduncular thalamoperforators (1st of 2 groups of posterior thalamoperforating aa.)
● medial post. choroidal (most from P1 or P2)
● “artery of Percheron”: a rare anatomic variant 1) in which a solitary arterial trunk arising from the proximal segment of one PCA supplies the paramedian thalami and rostral midbrain bilaterally
P1 of the posterior cerebral artery: from it origin at the termination of the basilar artery to posterior communicating artery (PCOM), within interpeduncular cistern.
(AKA mesencephalic, precommunicating, circular, peduncular, basilar…). The long and short circumflex and thalamoperforating arteries arise from P1