Uncommon Association of Two Anatomical Variants of Cerebral Circulation: A Fetal-Type Posterior Cerebral Artery and Inferred Artery of Percheron, Complicated with Paramedian Thalamomesencephalic Stroke—Case Presentation and Literature Review
Table 2
Variable branching patterns and origin of the TPAs, emerged unilaterally or bilaterally from the P1 arterial segment.
Type I (Park 38.5%)
TPAs bilaterally, multiple
TPAs bilaterally, multiple
Type II (Park 26.9%)
TPA unilateral, single
TPAs contralateral, multiple
Type III (Park 19.2%; Percheron 40%)
TPA single
TPA single
Type IV (variant IIb, AOP) (Park 11.5%; Percheron 33%)
TPAs arise unilaterally (from one P1, as multiple branches)
−
Percheron’svariant III (C): an arterial arcade is bridging P1 segments of both PCAs; the perforating branches arise from this arterial shunt.
TPAs, thalamoperforating arteries. P1, proximal arterial segment of the PCA (from the top of the basilar artery, to the PCoA). IIa and IIb, arterial variants of vascularization of the thalamus and midbrain described by Percheron. In brackets Park’s [13] and Percheron’s [7, 8] data are mentioned, respectively.