Variability of the venous drainage of brain

Abstract

Background. Chronic venous dyscirculation of the brain is one of the most common forms of cerebrovascular pathology, while the numerous scientific papers on the cerebral vessels are more concerned with the arterial system. Materials and methods. Thе 121 scientific sources were searched in databases: PubMed, Elsevier, Hinari. Ten formalin-fixed anatomical specimens of the human head from the muzeum, as well as, from dissecting room were analyzed. Results. According to numerous studies, only three dural sinuses are relatively constant - the superior sagittal, straight and cavernous. Thus, the presence of the superior sagittal, stright and cavernous sinuses was in 100% of cases, while others may be aberrant, hypoplastic, asimetric, bifid, double, triple, septated or absent. The main variations of the venous anatomy of the dural sinuses are: a- the bifid superior sagittal sinus connects to one transverse sinus and the straight sinus to the other; b-the superior sagittal sinus and straight sinus are forked with the connection to the left and the right transverse sinuses; c) torculum variations. Only three anastomotic veins are relatively constant: a - Superior anastomotic vein of Trolard; b - Superficial middle cerebral vein; c - Inferior anastomotic vein of Labbé. With the exception of wide variations of basal vein, the deep system is rather constant compared to the superficial venous system. There is no constancy in the formation of venous circles of the brain. There is a number of researches indicating differences in the venous circles of the base of brain in individuals of various constitutional types. There are variants of diploic veins, with regard to their sizes and anastomosеs. Conclusion. Considering the frequency of chronic venous circulation of the brain and the role of venous bed in the development of this pathology, more attention should be paid to the study of all links of the venous bed of head.