Microdissection Of Superior Sagittal Sinus

Objective: Investigate the general and microdissection of superior sagittal sinus, study the communication between superior sagittal sinus and the other sinus, the anatomy of fiber cables structures, arachnoid granulations and confluence of sinuses in the superior sagittal sinus, and to study the clinical significance of preferred direction of sinuses confluence shunts.Methods: Five adult skull specimens, which have been removed the calvaria, was observe the superior sagittal sinus with the follow items: general anatomy ,venous branches, the communication with the other venous sinus and the directions of confluence sinuses shunt. Longitudinal rip the superior sagittal sinus, to observe the anatomy of fiber cables structures, arachnoid granulations and initial anatomy of confluence of sinuses in the superior sagittal sinus cavity under the microscope.Results: Superior sagittal sinus collect the follow area's veins: the top lateral and medial surface of frontal lobe, parietal lobe and occipital lobe, together with the superior cerebral veins which is located in the frontal superficies inferia of the frontal lobe. The earlier middle pieces accepte the frontal pole vein, prefrontal veins, middle- forehead vein. The middle part accepte the postfronto vein, precentre vein, central veins, post-centre vein and pro-cupule vein. The posterior segment accept the post-cupule vein and occipital veins, and the veins from different regions of the brain cortex form a characteristic pattern of returning, when they abouchement into the superior sagittal sinus.In which pattern the superior cerebral veins come from the front part of the frontal lobe inject into the superior sagittal sinus in the direction of frontal to behind, which is the same as the flow in sinus does; the superior cerebral vein from the middle lobe drains into it in right angle, superior cerebral veins from the posterior part of frontal lobe,occipital and parietal lobe joins the superior sagittal sinus, which is opposite on the sinus blood flow. The direction of veins import into superior sagittal sinus are changing on its way: from the previous part in the same direction with the sinus flow, the middle paragraph in the almost perpendicular direction ,to the contrary direction of the last part,which is a gradual migration.Superior sagittal sinus connect with dural venous sinus by superficial middle cerebral veins, superior cerebral vein, superior anastomotic vein, inferior anastomotic vein. The anastomotic vein connected with superior sagittal sinus in cerebral falx make the superior sagittal sinus and the inferior sagittal sinus, straight sinus, transverse sinus together.In the structure fiber cable-shaped, the valve-shaped fiber cables were most common, and were found in all the superior sagittal sinus. This type was closely related to the openning of vein, covered most entrance of superior cerebral vein. The second was the trabeculum-shaped fiber cable, which may be longer or shorter, and located in the central of sinuses cavity, sometimes in one side, some trabeculum-shaped fiber cables situated in the opening of vein behind valve-shaped fiber cables. Lamellar-shaped fiber cables were most rare, mainly located in the posterior segment of superior sagittal sinus, and divided the sinuses cavity into two parts by vertical or oblique.Used microscope to obseved, arachnoid granulations are more concentrated in the middle of the superior sagittal sinus, sizes were different, also can be a single, often intruded into the sinuses cavity near the wall and lateral recess of vein. Under the microscope it looks like the pink grape granular. The arachnoid granulations were observed in 90 times, linear structures were visible near the edge of particles, also observed the removing liquid.Lateral recesses often located on both side of the superior sagittal sinus, also it is the cavity of dural near the sagittal sinus, the ranges were different. Some middle parts of the great cerebral vein influxed into it directly, others extended to sinuses after entering the lateral recesses, and then influxed into the lateral side or floor of superior sagittal sinus . The lateral recesses were normally found in the median part of superior sagittal sinus, other parts almost couldn`t be found. The shapes mainly were strip-shaped or egg-shaped, long axis paralleled with superior sagittal sinus, outer margins were irregularity, and the sizes were different predominance. The distance from lateral recesses to the median line of superior sagittal sinus exceeded 2cm. The internal of lateral recesses were abundance of arachnoid granulations, the handhole of superior cerebral vein, the entering of lateral recesses, valve-shaped fiber cables and trabeculum-shaped fiber cables could be observed in it.The vertical lamellar fiber cables can be seen in the end-piece of superior sagittal sinus and confluens sinus, and divided the end-piece lumina into tow lonely cavity. All the right channel was bigger than the left in 10 specimens that be detection, and the direction passageway could be seen between the opening of straight sinus and the confluens sinus. The direction of split stream of confluens sinus turned to the right in 10 specimens, the diameter of the right transverse sinuswas wider than the left.Conclusion:1. The results confirmed that the superior cerebral vein from the prefrontal lobe drains into the superior sagittal sinus, and the direction of blood flow is the same with the sinuses, the superior cerebral vein from the middle lobe drains into it in right angle, superior cerebral veins from the posterior part of frontal lobe,occipital and parietal lobe joins the superior sagittal sinus, the direction of blood flow is opposite to the sinuses2.The fiber cable of superior sagittal sinus cavity contained three types:valve-shaped, trabeculum-shaped, lamellar. The valve-shaped fiber cables were mostly be seen.3. The length wise structures near the border of the arachnoid granulations were the passageway of cerebrospinal fluid, the end of it communicated with the lateral recesses or sinuse, and transported the cerebrospinal fluid to the the lateral recesses and sinuse.4. Lateral recesses often located on both side of the superior sagittal sinus, also it is the cavity of dural near the sagittal sinus, the ranges were different. Some middle parts of the superior cerebral vein influxed into it directly, others extended to sinuses after entering the lateral recesses, and then influxed into the lateral side or floor of superior sagittal sinus . The distance from lateral recesses to the median line of superior sagittal sinus exceeded 2cm, maximum distance is 2.6cm.5. The vertical lamellar fiber cables can be seen in the end-piece of superior sagittal sinus and confluens sinus, and divided the end-piece lumina into two lonely blood refluxing passageway. In the specimens that the confluence sinuum trund to right, the right channel was bigger than the left, the diameter of the right transverse sinuswas wider than the left. The confluens sinus could be advantage of bridging;shunt...