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Anatomy of Neck and Blood Supply of Brain
Published in Sudhir K. Gupta, Forensic Pathology of Asphyxial Deaths, 2022
Most of the sinuses converge at the confluence of sinuses located near the internal occipital protuberance and then on either side traverse as transverse sinuses, which continue as sigmoid sinuses finally forming the internal jugular vein. The cavernous sinus through the superior or inferior petrosal sinuses drains into the internal jugular vein. Internal jugular vein is continuation of sigmoid sinus, and it traverses down through the jugular foramen and enters the carotid sheath in the neck.
Neuroanatomy overview
Published in Michael Y. Wang, Andrea L. Strayer, Odette A. Harris, Cathy M. Rosenberg, Praveen V. Mummaneni, Handbook of Neurosurgery, Neurology, and Spinal Medicine for Nurses and Advanced Practice Health Professionals, 2017
All cerebral drainage ultimately terminates through the jugular veins. The confluence of sinuses is where the straight sinuses, the superior sinuses, and the occipital sinuses meet and then drain into the transverse sinus, which in turn drains into the sigmoid sinus, then into the cavernous sinus, to the superior petrosal sinus, then to the inferior petrosal sinus, and into the inferior jugular vein. This drainage system is unlike any other in the body as it operates without valves or muscles.
Neurology cases
Published in Lt Col Edward Sellon, David C Howlett, Nick Taylor, Radiology for Medical Finals, 2017
The image demonstrates extensive low signal filling defect (C) within the superior sagittal sinus posteriorly in keeping with thrombus. The filling defect extends posteriorly to the confluence of sinuses (at the level of the tentorium cerebelli). Label D points to the normal bony cranium, which has low signal. E is the cerebellum and F is the sinus confluence.
Anatomic variations of the human falx cerebelli and its association with occipital venous sinuses
Published in British Journal of Neurosurgery, 2021
Safiye Çavdar, Bilgehan Solmaz, Özgül Taniş, Orhan Ulas Guler, Hakkı Dalçık, Evren Aydoğmuş, Leyla Altunkaya, Erdoğan Kara, Hızır Aslıyüksek
The occipital sinus, is the smallest dural venous sinus, and communicates superiorly with the confluence of sinuses (torcular herophili) and inferiorly with the posterior internal vertebral plexus and receives tributaries from the cerebellum and medulla and drains the choroid plexus of the fourth ventricle.3
Occipital petalia as a predictive imaging sign for transverse sinus dominance
Published in Neurological Research, 2019
Ezgi Yetim Arsava, Ethem Murat Arsava, Kader Karlı Oguz, Mehmet Akif Topcuoglu
In addition to functional implications, another critical feature is the role of developmental factors that might be related to the formation of anatomic asymmetries. The close relationship between the direction and presence of occipital bending and transverse sinus asymmetry, pointed out in our study, is an additional observation emphasizing the importance of embryonic developmental factors in the concept of petalia. Unequal venous drainage pattern of transverse sinuses is a well-known phenomenon; studies performed in the framework of venous drainage patterns of cerebral hemispheres have shown that in most cases the flow was towards the right transverse sinus, and based on luminal measurements in cadaver sections, it was calculated that transverse sinus and internal jugular vein diameters were wider at the side of higher flow [23]. When this asymmetry was traced back to the embryological developmental stages, Streeter [24] reported in 1915 that superior sagittal sinus drainage was towards the right transverse sinus in the majority of the embryos he examined. The specimen that had the smallest length in those 18 embryos was 17 mm (gestational age: ~9 weeks, Carnegie stage 18–19 [25]). A subsequent study has contributed to this observation by showing evidence for torcular herophili asymmetries even in earlier stages of embryological development (embryo length: 8–16 mm; gestational age: ~8–9 weeks, Carnegie stage 15–19) [26]. This asymmetry, which is generally characterized by a dominant right venous drainage system, and thereby a larger transverse sinus on the right side, is considered to follow the development patterns of major veins draining into the heart. Although these veins, known as anterior cardinal veins, are initially symmetric in terms of size and drainage patterns, the left-sided vein starts to take a longer and angulated course to reach the elongating sinus venosus (the preceder of adult atrium) during the second embryological developmental stage, while the right-sided vein maintains its direct connection with the right atrium [26]. It is speculated that this pattern, characterized by the absence of an analog of superior vena cava on the left side, leads to an increase in the vascular resistance and gradually causes a shift of the venous drainage to the right side. This shift, in turn, causes slight rightward displacement of superior sagittal sinus from the midline in its posterior parietal and occipital course, and asymmetric expansion in confluence of sinuses [23]. Our findings highlight that this sinovenous asymmetry is also closely related to the direction of occipital bending, possibly secondary to the traction forces originating from the falx (which is fixed to the sinus system) and acting on the interhemispheric fissure and occipital lobe [27], thereby causing the bending of the occipital lobe to the dominant side of venous flow.