Microsurgical anatomy of the upper basilar artery and the posterior circle of Willis

摘要: ✓ The microvascular anatomy of the posterior part circle Willis, important in surgery pituitary tumors and basilar aneurysms, was defined 50 cadaver brains. Significant findings were as follows: 1) Anomalies half Willis found 46% cases. 2) Hypoplastic P-1 (posterior cerebral segment) communicating segments gave origin to same number size perforating arteries, having termination normal-sized segments. Thus hypoplastic should be handled with care divided aid exposure bifurcation only after careful consideration. 3) An average four branches arose from P-1; most superior surfaces. No anterior surface bifurcation. proximal branch originated 2 3 mm distal It commonly a thalamoperforating artery. largest usually or ...