Dural entrance of the bridging vein into the transverse sinus provides a reliable measure for preoperative planning: an anatomic comparison between cadavers and neuroimages.

OBJECTIVE: Understanding the anatomy of the transverse sinus and its associated bridging veins (BVs) is essential to approaching the posterior and middle incisural space. The venous phase of neuroimages has received increasing attention in preoperative planning. The aims of this study are to identify anatomic features of the dural entrance of the BVs into the transverse sinus on the cadaver and to correlate such features with those of digital subtraction angiography (DSA), computed tomographic venography (CTV), and magnetic resonance venography (MRV).
METHODS: A total of 30 adult cadavers and 76 patients were examined through anatomic dissection and DSA, CTV, and MRV, respectively. The number, diameter, and location of the BVs entering the sinus were measured, and comparisons were made between the cadavers and neuroimages.
RESULTS: We found that the way BVs entered the transverse sinus varied but was identifiable in DSA, CTV, and MRV images. Compared with the cadavers, DSA, CTV, and MRV revealed less than 50% of the BV entering the sinus because the smaller BVs were not seen on the neuroimages. However, the distribution pattern of the dural entrance of the BVs into the transverse sinus was relatively consistent between cadavers and neuroimages.
CONCLUSION: Unique anatomic features of the dural entrance of a BV into the transverse sinus in the cadaver correspond to those evident in neuroimages; thus, identification of the dural entrance of the BVs with neuroimaging modalities provides a reliable measure for preoperative planning.