Abstract:

Objective〓〖WTBZ〗To explore the regulatory mechanism of muscular ultra-microstructures of the outflow segments on blood flowing out from the cerebral bridging veins. 〖WTHZ〗Methods〓〖WTBZ〗Bridging veins were obtained from patients suffering from non-venous disorder diseases of the central nervous system. The junctures of bridging veins were completely isolated as close as possible to superior sagittal sinus and sliced. Then serial sections of the outflow segments were observed by transmission electron microscopy. 〖WTHZ〗Results〓〖WTBZ〗Muscular morphological features of
the outflow segments of cerebral bridging veins were obviously different from those of other parts of the cerebral vein system. Sporadic and isolated smooth muscle cells were discovered by electron microscopy, but no nerve fibers and no gap junctions were found between cells. 〖WTHZ〗Conclusion〓〖WTBZ〗The outflow segment of bridging veins can not functionally contract and dilate， the control mechanism here must be passive. Its special morphological pattern indicates that the outflow segment is the possible key point to control vein outflow and so it is a possible key point to regulate intracranial hypertension.

Key words: Cerebral bridging veins, Ultra microstructure, Intracranial hypertension