The basal vein of Rosenthal originates on the medial surface of the temporal lobe and runs posteriorly and medially. It passes lateral to the midbrain through the ambient cistern to drain into the vein of Galen. It is closely related to the posterior cerebral artery (PCA).
In the literature recent studies have suggested a possible contribution by primitive variants of Basal vein of Rosenthal (BVR) in the pathogenesis of idiopathic subarachnoid hemorrhage (ISAH), commonly grouped according Watanabe classification (type A, B and C).
Sabatino et al, evaluated the prevalence of anatomical variants of BVR in ISAH.
Previous studies displayed a significant prevalence of BVR type C variants in ISAH. Conversely recognized variant B as prevalent, in which the BVR bifurcates to drain anteriorly into the uncal vein and posteriorly into the Galenic system. Similarly to variant C (in which the BVR drains via perimesencephalic “bridging” veins into cavernous, sphenoparietal, petrosal sinus or directly into transverse sinus) also variant B might be subjected to those stress mechanisms and intrinsic system 'fragility' and for reasons yet to determine, sets off a consequent hemorrhage with clinical and radiological features typical of ISAH 1).
There is a relationship between perimesencephalic subarachnoid hemorrhage (P-SAH) and Basal Vein of Rosenthal primitive drainage type. P-SAH risk increases in parallel with decreasing caliber of BVR in patients with normal drainage pattern 2).