Anatomical Variation Of The Galen's Venous System And Straight Sinus In Surgical Management For Pineal Region Lesions

Objective: To evaluate the anatomical variations of the galenic venous system and their effects in the surgical management of pineal region lesions based on the study of 3D-CTA imaging.Methods: The galenic vein,the internal cerebral vein,the basal vein and the internal occipital vein were measured on 3D—CTA images of 60 normal brains, the angle between the straight sinus and the galenic vein,the shape between two internal cerebral veins,the variations of the basal vein,the internal occipital vein and the precentral cerebellar vein were also analyzed.Resuls: The diameter of GV was 4.7±1.5 mm and the length was 10.30±4.2mm, the diameter of ICV was 2.56±0.37mm and the length was 35.1±2.9mm,the diameter of BV was 2.20±0.2mm and the length was 35.3±6.5mm. the diameter of IOV was 1.64±0.5 mm and the length was 12.3±5.5mm and the diameter of PCV was 1.40±0.3mm and the length was 5.8±2.5mm.The angles between the straight sinus and the galenic vein were divide into actue angle (95%) and obtuse angle (5%),the average angle was 75.20±10.5o. The shapes between two internal cerebral veins were subgrouped into three types: the rhombus shape (60%),the hairpin shape (35%) and the parallel shape (5%). The basal veins poured into either the galenic veins (80%) or the internal cerebral vebins (20%). The internal occipital vein inflowed either the galenic vein (80%) or the internal cerebral vein (10%) or the basal vein (10%). Some veins of the basal veins,the internal occipital veins and the precentral cerebellar veins were very wide.Conclusion: Great anatomical variations were found in the galenic venous system. The preoperative understanding of the anatomical variations of galenic venous system,combined with the position relationship between the lesions and venous system according to the 3D-CTA, will play an important role in surgical management of pineal region lesions.