Vein of Labbe thrombosis by CT and MRI
- 1Department of Neurology, UTMB, Galveston, Texas, USA
- 2Department of Radiology, UT Houston, Houston, Texas, USA
- 3Department of Radiology, MD Anderson, Houston, Texas, USA
- Correspondence to Dr Girish Shroff, UT Houston Department of Radiology, 6431 Fannin St. MSB 2.130B, Houston, TX 77030, USA;
Contributors All authors contributed significantly to this manuscript and have read and approved this submitted draft.
- Received 16 May 2012
- Revised 27 June 2012
- Accepted 29 June 2012
- Published Online First 28 July 2012
A 66-year-old man with tongue carcinoma presented to the emergency room (ER) with decreased oral intake for one week. In the ER, he experienced a generalised seizure. Neurological examination was non-focal. Noncontrast CT brain revealed bandlike high attenuation along the course of the left vein of Labbe (figure 1). Findings suggested vein of Labbe thrombosis and were confirmed with MRI and magnetic resonance venography (MRV) (figure 2).
The vein of Labbe is part of the superficial cerebral venous system of the temporal lobe. It drains the lateral surface of the temporal lobe and the region adjacent to the sylvian fissure. The vein generally arises within the sylvian fissure and travels posteriorly and inferiorly before emptying into the transverse sinus.
Isolated vein of Labbe thrombosis is rare. Cortical vein thrombosis is usually secondary to retrograde extension of dural sinus thrombosis. Risk factors for the development of venous thrombosis include thrombophilia, pregnancy/puerperium, malignancy, oral contraceptive use and central nervous system or head/neck infections.
Almost all reported cases of isolated vein of Labbe thrombosis have occurred on the left.1–4 The most common presenting symptoms of isolated vein of Labbe thrombosis include seizure and headache.1 ,2 ,4 Other reported findings include dysarthria, receptive aphasia, motor aphasia, amnestic aphasia, alexia, agraphia, acalculia and hemiparesis.1–4 Dorndorf et al reported a case of isolated right vein of Labbe thrombosis.3 The patient experienced a generalised seizure preceded by headache. Examination revealed left facial paresis, left arm weakness and sensory loss, and pyramidal signs on the left. Altered consciousness and papilloedema, findings associated with increased intracranial pressure in cases of venous sinus thrombosis, are not reported with vein of Labbe thrombosis.
Radiological diagnosis of vein of Labbe thrombosis requires a high degree of suspicion. CT may directly visualise the thrombosed vein of Labbe as a hyperdense structure apposed to the cortical surface of the temporal lobe. Indirect signs are more common and include temporal lobe infarction, haemorrhage, or oedema. MRI/MRV is the imaging modality of choice when vein of Labbe thrombosis is suspected. On MRI, signal intensity of venous thrombus varies according to age of the thrombus.5 In the acute stage (0–5 days), signal intensity is predominantly isointense on T1-weighted images and hypointense on T2-weighted images and is related to deoxyhemoglobin in red cells within the thrombus. In the subacute stage (6–15 days), signal intensity is predominantly hyperintense on both T1- and T2-weighted images due to accumulation of methaemoglobin in the thrombus. Signal intensity in chronic thrombus is typically isointense or hyperintense on T2-weighted and isointense on T1-weighted images.5 Ultimately, recanalisation leads to progressive signal loss and return of the normal flow void. The T2-gradient recalled echo sequence is the most sensitive sequence in the acute stage.5 The thrombosed vein manifests as low signal secondary to magnetic susceptibility effect.5 MRV techniques include time-of-flight (TOF) MRV and contrast-enhanced MRI/MRV. The latter may offer improved visualisation of veins as artifactual flow gaps are frequently seen on TOF MRV.
Competing interests None.
Provenance and peer review Not commissioned; externally peer reviewed.