Abstract:

        Objective   To correlate microanatomy of cerebellar bridging veins below the tentorium with its venograms，and provide anatomic basis for the preservation of cerebellar bridging veins during the infratentorial supracerebellar route.  Methods  A total of 20 human cadavers (40 sides) and 62 patients (120 sides) were examined in this study. Each head of the cadavers was injected with blue-coloured latex via the superior sagittal sinus and internal jugular veins. The venograms of each patient was obtained from the venous phases of digital subtraction angiography (DSA) (40 sides out of 22 patients) or computed tomographic venography (CTV) (40 sides out of 20 patients) or magnetic resonance venography (MRV) (40 sides out of 20 patients). Results  Compared to the cadavers, DSA, CTV and MRV revealed 89%, 40% and 38% of the cerebellar bridging veins because the veins depicted by the imageology were 11%, 17% and 33% larger than that of the cadavers. The cerebellar bridging veins entered into TS and petrosal sinus either directly or indirectly via meningeal "lake". The lumen of the meningeal "lake" was flattened, and discontinuity, weaken or intensive signal was often observed on neuroimagings. The dural entrence of cerebellar bridging veins were clustered along the medial end of transverse sinus, the tentorial sinus and the antero-medial segment of the petrosal sinus.  Conclusions  The preoperative venogram is useful to design the individualized surgical approach for the preservation of cerebellar bridging veins below the tentorium.

Key words: Bridging veins, Infratentorial supracerebellar route, Microanatomy, Imageology