Delineation of lateral tentorial sinus with contrast-enhanced MR imaging and its surgical implications

Abstract

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.

Fig 1.

Direct superior of the LTS. 1, anterior temporal vein; 2, anterior temporobasal vein; 3, middle temporobasal vein; 4, posterior temporobasal vein; 5, occipitobasal vein; 6, posterior temporal vein; 7, vein of Labbé; 8, middle temporal vein.

Fig 2.

LTS venous configuration. A, Type I, venous candelabra. B, Type II, multiple independent veins. C, Type III, venous lakes within tentorium (14).

Fig 3.

Type I LTS. Axial contrast-enhanced T1-weighted MR image obtained in a 37-year-old man shows several branches of the right LTS. 1, anterior temporobasal vein; 2, middle temporobasal vein; 3, posterior tomporobasal vein; 4, occiptiobasal vein; 5, posterior temporal vein; 6, vein of Labbé; 7, middle temporal vein. Left LTS is not well depicted on this image.

Fig 4.

Types I and II LTS. Axial contrast-enhanced T1-weighted MR image obtained in a 55-year-old man with a type I LTS on the left and a type II LTS on the right. Right vein of Labbé terminates into the transverse sinus (arrow). 1, superior petrosal sinus; 2, anterior temporobasal vein; 3, middle temporobasal vein; 4, posterior temporobasal vein; 5, occipitobasal vein; 6, middle temporal vein; 7, posterior temporal vein; 8, vein of Labbé.

Fig 5.

Types II and III LTS. Axial contrast-enhanced T1-weighted MR image obtained in a 34-year-old woman shows a type II LTS on the left and a type III LTS on the right side (black arrows). The veins of Labbé are draining separately into the transverse-sigmoid sinus junction (white arrows). 1, superior petrosal sinus; 2, middle temporobasal vein; 3, posterior temporobasal vein; 4, occipitobasal vein; 5, vein of Labbé.

Fig 6.

Type III LTS. Axial contrast-enhanced T1-weigthed MR image obtained in a 57-year-old man depicts “venous lakes” of a type III LTS (black arrow) and the left vein of Labbé just before it drains into the transverse sinus (white arrow). 1, middle temporobasal vein; 2, posterior temporobasal vein; 3, posterior temporal vein; 4, vein of Labbé.

Fig 7.

Anterior temporal vein and anterior temporobasal vein common trunk. Axial contrast-enhanced T1-weighted MR image obtained in a 45-year-old woman with a type I LTS on the right side. Anterior temporal and anterior temporobasal branches form a trunk (arrow) before draining into the LTS. 1, anterior temporobasal vein; 2, posterior temporal vein; 3, vein of Labbé; 4, anterior temporal vein.

Fig 8.

Vein of Labbé termination into the LTS. Axial contrast-enhanced T1-weighted MR image obtained in a 39-year-old man shows the VL draining into a type I LTS (arrow). 1, anterior temporobasal vein; 2, middle temporobasal vein; 3, posterior temporobasal vein; 4, occipitobasal vein; 5, posterior temporal vein; 6, vein of Labbé.

Fig 9.

Termination of the vein of Labbé into the transverse sinus. Axial contrast-enhanced T1-weighted MR image obtained in a 42-year-old woman shows the right vein of Labbé (arrow) as it drains into the transverse-sigmoid sinus junction. 1, vein of Labbé; 2, middle temporobasal vein.

Fig 10.

Arachnoid granulation in type III LTS. Axial contrast-enhanced T1-weighted MR image obtained in a 61-year-old woman shows multiple venous tributaries of a type III LTS. Note the close relationship between the vein of Labbé and the arachnoid granulation (arrow). 1, vein of Labbé; 2, anterior temporobasal vein; 3, middle temporoabasal vein; 4, posterior temporobasal vein; 5, occipitobasal vein; 6, posterior temporal vein.

Fig 11.

Tentorial meningioma displacing a type III LTS. Axial T1-weighted contrast-enhanced MR image obtained in a 64-year-old man shows a posterior fossa meningioma (asterisk) compressing the transverse sinus and distorting the nearby LTS (arrow). Note that the transverse sinuses are codominant and that the confluence of sinuses is widely patent. 1, superior petrosal sinus; 2, anterior temporobasal vein; 3, vein of Labbé; 4, occipitobasal vein.

Fig 12.

Sphenopetrosal sinus in a patient with a petroclival meningioma. A, Left common carotid artery injection, venous phase image obtained in a 61-year-old woman who presented with persistent headache reveals sphenotemporal sinus (arrowhead) draining into the transverse-sigmoid sinus junction (arrow). B−D, Axial contrast-enhanced T1-weighted MR images again show a left petroclival meningioma (asterisks) and sphenopetrosal sinuses (arrows) emptying into transverse-sigmoid sinus junction, which is better seen on the right side (arrowhead). 1, superior petrosal sinus; 2, vein of Labbé; 3, occipitobasal vein; 4, posterior temporal vein; 5, middle temporal vein.