A cadaveric study of superior sagittal sinus and its draining veins among population in Sabah, Malaysia

Abstract

The superior sagittal sinus and its draining veins are important venous structures that pose a formidable obstacle to surgical management. It is crucial and essential for the surgeon to acquire the knowledge of the normal course and variations of the sinus and its draining veins. This helps in pre-operative planning and execution of pre-operative measures or manoeuvres needed to minimize blood loss or intra-operative injuries to the sinus.This study was conducted to delineate the microsurgical anatomy of the superior sagittal sinus to look for any variations among Sabah people as compared to the general studies available. This study was based on dissection of fresh cadavers. Thirty fresh cadavers were examined in Forensic Department, Hospital Queen Elizabeth, Sabah between August 2020 to June 2021. They were anatomically analysed and studied through a data collection sheet. All data were analysed using Statistical Package for the Social Science (SPSS). The study revealed that male was predominantly significant and forty-three percent were of Bajau race. Fifty percent of cadavers were around the 50-60 years old age group. The position of superior sagittal sinus (SSS) was variable and within 1cm distance from the midline. The origin of SSS varied from at the foramen caecum to posterior from the foramen caecum. The total length of SSS averages around 321-351mm. The number of draining veins on the right and left side of SSS were divided into anterior, middle and posterior components with an average of three to six veins respectively on each side. The number of venous lacunae on the right and left side of SSS were divided as well into anterior, middle and posterior components with an average of one to two venous lacunae on each side respectively. The central sulcus was located 48.87mm posterior to coronal suture and 131.1mm anterior to the lambdoid suture. The Trolard vein was located 53.56mm posterior to coronal suture and 127.36mm anterior to the lambdoid suture. The Trolard vein was situated in average 3.68mm posterior to central sulcus and predominantly drains into the venous lacuna. Ninety percent of SSS terminate on the right of the transverse sinus. The position of torcula varies from the location on the external occipital protuberance to slightly on the right side of the external occipital protuberance. This study shows that anatomical landmarks among the local population did not differ significantly from that reported by other studies throughout the world. Therefore, the basic neurosurgical principles and craniometric points outlined universally is applicable to this population without the need for any modifications.