Introduction: To investigate the anatomical variations of the galenic venous system using three-dimensional computed tomography venography (3D-CTV) and to evaluate their impact on surgical management of pineal region lesions.
Methods: The galenic vein (GV), internal cerebral vein (ICV), basal vein (BV), internal occipital vein (IOV) and precentral cerebellar vein (PCV) of 60 adult brains were measured on 3D-CTV images, and the angle between the straight sinus and GV, the shape between the bilateral ICVs, and the variations of the BV, IOV and PCV were analyzed.
Results: The mean diameter of the GV was 4.7 ± 1.5mm with a mean length of 10.30 ± 4.2mm; the mean diameter of ICV was 2.56 ± 0.37mm with a mean length of 35.1 ± 2.9mm; the mean diameter of BV was 2.20 ± 0.2mm with a mean length of 35.3 ± 6.5mm; the mean diameter of IOV was 1.64 ± 0.5mm with a mean length of 12.3 ± 5.5mm; the mean diameter of PCV was 1.40 ± 0.3mm with a mean length of 5.8 ± 2.5mm. The angles between the straight sinus and the GV included acute angle (95%) and obtuse angle (5%), with an average angle of 75.20 ± 10.5º. The shapes between the two ICVs were subgrouped into three types: rhombus shape (60%), hairpin shape (35%) and parallel shape (5%). The BV flowed into either the GV (80%) or the ICV (20%). The IOV flowed into either the GV (80%), the ICV (10%) or the BV (10%). Some of the BVs, IOVs and PCVs were enlarged in diameter.
Conclusions: Great anatomical variations were found in the galenic venous system. Preoperative understanding on the anatomical variations of the galenic venous system and its position relationship with the lesions based on 3D-CTV is of great significance for selection of surgical approaches for management of pineal region lesions.
Patient Care: this study provided anatomic basis for surgery in pineal region
References: 1. Bruce JN, Stein BM. Surguical Management of pineal region tumors. Acta Neurochir(Wein)134:130~135,1995
2. Chaynes P. Microsurgical anatomy of the great cerebral vein of Galen and its tributaries. J Neurosurg. 2003 Dec;99(6):1028-38.
3. Chaynes P. Microsurgical anatomy of the venous drainage of the mesencephalodiencephalic junction. Neurosurgery. 2004 Mar;54(3):678-85.
4. Duvernoy HM, Parratte B, Tatu L, Vuillier F. The human pineal gland: relationships with surrounding structures and blood supply. Neurol Res. 2000 Dec;22(8):747-90.
5. Giodarno M, Wiede KH, Stieglitz LH, Columbano L, Samii M, Luedermann WO. Depiction of small veins draining into the vein of Galen using preoperative 3-Dimensional navigation in living patients. Operative Neurosurgery 2009, May64(9):247~253.
6. Kilic T, Ozduman K, Cavdar S, et al. The galenic venous system: Surgical anatomy and its angiographic and magnetic venographic correlations. Eur J Radiol 2005,Nov56(2):212~219.
7. Yamamoto I. Pineal region tumor: surgical anatomy and approach. J Neurooncol,2001,54(3):263~275 .
8. MaoY, Zhou LF. Tumors of the pineal region and the third ventricle. Zhou-LF edited: modern neurosurgery, Shanghai: Shanghai Scientific & Technical Publisher, 2001:510-522.