American Journal of Neuroradiology 25:1181-1188, August 2004
© 2004 American Society of Neuroradiology
BRAIN
Delineation of Lateral Tentorial Sinus with Contrast-Enhanced MR Imaging and Its Surgical Implications
a Department of Radiology, Tabriz University, Tabriz, Iran
b Department of Radiology, University of Michigan Health System, Ann Arbor, MI
c Departments of Radiology, Dalhousie University, Halifax, Nova Scotia
d Departments of Neurosurgery, Dalhousie University, Halifax, Nova Scotia
Address reprint requests to Mehran Midia, MD, 216 Plains Road West, Unit E104, Burlington, Ontario, L7T 4L3, Canada
BACKGROUND AND PURPOSE: The lateral tentorial sinus (LTS) has not been well described in the imaging literature. The aim of this study was to investigate the value of MR imaging in assessing the LTS, which may provide guidance for preoperative planning.
METHODS: Fifty-five adult patients underwent MR imaging of the brain. Four neuroradiologists evaluated the studies for delineation of the LTS and its branches. Presence of arachnoid granulation and dominance of the venous drainage also were reported.
RESULTS: An LTS was detected in 104 of 110 lobes. The LTS in each lobe was classified as type I (candelabra) in 30 (28.8%), type II (independent veins) in 22 (21.1%), and type III (venous lakes) in 37 (35.5%); in 15 (14.4%) of the lobes, the LTS was indeterminate. LTS branches were inconsistently detected, with the exception of the vein of Labbé (VL). Five of eight branches were seen in approximately half of the cases. The VL was identified in 94 (85.4%) lobes. Among these, 53 (56.4%) were draining into the LTS and 22 (23.4%) into the transverse sinus; in 19 (20.2%) cases, the terminal portion was not visualized. The right transverse sinus was dominant in 19 (34.5%) patients and the left in 18 (32.7%); codomination was present in 18 (32.7%) cases. At least one arachnoid granulation was seen in the transverse sinus in 27 (49.1%) patients.
CONCLUSION: In many instances, the LTS and VL drainage patterns were well delineated on routine MR images. For selected cases, this information may be crucial during lateral skull base surgery to avoid venous infarct.