Department of Neurosurgery, Brigham and Women's Hospital, Boston, Massachusetts, USA; Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA; Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
Department of Neurosurgery, Hospital Beneficência Portuguesa de São Paulo, Institute of Neurological Science of São Paulo Bela Vista, São Paulo, Brazil.
World Neurosurg. 2019 Nov;131:e38-e45. doi: 10.1016/j.wneu.2019.06.232. Epub 2019 Jul 9.
Described variations of tentorial venous anatomy impact surgical sectioning of the tentorium in skull base approaches; however, described configurations do not consistently explain postoperative complications. To understand the outcomes of 2 clinical cases we studied the tentorial venous anatomy of 2 cadavers.
The venous anatomy of the tentorium isolated in 2 uninjected fresh cadaver head specimens with preserved bridging veins was observed by transillumination before and after methylene blue injection of the dural sinuses and tentorial veins. Our findings in cadavers were applied to explain the clinical and radiologic (magnetic resonance imaging and computed tomographic venography) findings in the 2 cases presented.
A consistent transtentorial venous system, arising from transverse and straight sinuses, communicating with supra- and infratentorial bridging veins was seen in the cadaver and patient radiography (magnetic resonance imaging and computed tomographic venography). Our first patient had a cerebellar venous infarct from compromise of the venous drainage from the adjacent brain after ligation of a temporal lobe bridging vein to the tentorium. Our second patient suffered no clinical effects from bilateral transverse sinus occlusion due to drainage through the accessory venous system within the tentorium.
Herein, we elaborate on transtentorial venous anatomy. These veins, previously reported to obliterate in completed development of the tentorium, remain patent with consistent observed configuration. The same transtentorial venous system was observed in both cases and provided insight to their outcomes. These findings emphasize the importance of the transtentorial venous system physiologically and in surgical approaches.
天幕静脉解剖结构的变异会影响颅底手术中天幕的切开，但描述的结构并不能始终解释术后并发症。为了了解 2 个临床病例的结果，我们研究了 2 具尸体的天幕静脉解剖结构。
在 2 具未注射新鲜尸体头颅标本中，通过对硬脑膜窦和天幕静脉进行亚甲蓝注射前后的透照，观察未被注射的天幕静脉解剖结构。我们在尸体上的发现被应用于解释 2 个病例的临床和影像学（磁共振成像和计算机断层静脉造影）发现。
在尸体和患者影像学（磁共振成像和计算机断层静脉造影）中，我们观察到一致的天幕下静脉系统，由横窦和直窦起源，与幕上和幕下桥静脉沟通。我们的第一个患者由于颞叶桥静脉结扎至天幕导致毗邻脑组织静脉引流受阻而发生小脑静脉梗死。我们的第二个患者由于天幕内辅助静脉系统的引流，双侧横窦闭塞没有产生临床影响。
本文详细阐述了天幕下静脉解剖结构。这些静脉以前被报道在天幕完全发育过程中会消失，但在观察到的一致结构中仍保持通畅。在这两个病例中都观察到了相同的天幕下静脉系统，这为它们的结果提供了启示。这些发现强调了天幕下静脉系统在生理和手术入路中的重要性。
