Department of Neurosurgery, Keio University School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo, 160-8582, Japan.
Department of Diagnostic Radiology, Keio University Graduate School of Medicine, 35 Shinano-machi, Shinjuku-ku, Tokyo, 160-8582, Japan.
Acta Neurochir (Wien). 2019 Apr;161(4):821-829. doi: 10.1007/s00701-019-03857-w. Epub 2019 Feb 23.
The bridging vein (BV) and the tentorial sinus (TenS) are important venous structures in neurological surgery. These venous structures during the anterior transpetrosal approach (ATPA) have not been reported. The objective of this study is to examine the BV and the TenS in the subtemporal corridor during the ATPA and propose a technique to identify the BV preoperatively.
This study included 126 patients treated via the ATPA. The BV and the TenS located in the operative fields were analyzed. Furthermore, in the preoperative evaluation, the cross-sectional shapes of the intradural vein and the interdural sinus were analyzed by curved planar reconstruction (CPR), and the flattening rate was calculated. Flattening rate = (a-b)/a = 1-b/a (a: long radius, b: short radius).
Seventeen BVs and 18 TenS were identified. The bridging site was divided into two groups: tentorial and middle fossa. The middle fossa group was divided into three subgroups: cavernous sinus, middle fossa dural sinus, and middle fossa dural adherence. Five isolated TenS were sacrificed and no venous complications were observed. The mean flattening rate was 0.13 in the intradural vein and 0.51 in the interdural sinus, respectively (P = 0.0003).
We showed classification of the BV, and preservation of the BV and TenS during the ATPA. Furthermore, we found that the interdural sinus was significantly flatter than the intradural veins. Measuring the flattening rate by CPR may be useful to identify BVs preoperatively.
桥静脉（BV）和天幕窦（TenS）是神经外科中的重要静脉结构。目前尚未有研究报道过在前经岩骨入路（ATPA）中这些静脉结构的相关情况。本研究旨在探讨在 ATPA 中经颞下通道时的 BV 和 TenS，并提出一种术前识别 BV 的技术。
本研究纳入了 126 例行 ATPA 治疗的患者。分析了位于手术区域内的 BV 和 TenS。此外，在术前评估中，通过曲面重建（CPR）分析了硬脑膜内静脉和硬脑膜间窦的横断形状，并计算了压扁率。压扁率=（a-b）/a=1-b/a（a：长半径，b：短半径）。
共识别出 17 条 BV 和 18 条 TenS。桥接部位分为两组：天幕和中颅窝。中颅窝组进一步分为三组：海绵窦、中颅窝硬脑膜窦和中颅窝硬脑膜粘连。5 条孤立的 TenS 被牺牲，未观察到静脉并发症。硬脑膜内静脉的平均压扁率为 0.13，硬脑膜间窦的平均压扁率为 0.51（P=0.0003）。
本研究展示了 BV 的分类，以及在 ATPA 中保留 BV 和 TenS 的方法。此外，我们发现硬脑膜间窦明显比硬脑膜内静脉更平坦。通过 CPR 测量压扁率可能有助于术前识别 BV。
