[The clinical and imaging study of thalamic venous infarction]

To explore the clinical and radiological features of bilateral thalamus venous infarction.

The cases definitely diagnosed as thalamus venous infarction were collected and the corresponding clinical and radiological data were retrospectively analyzed.

Four cases confirmed as thalamus venous infarction by digital substraction angiography (DSA) were collected. Bilateral thalamus lesions were detected in all cases by brain MRI scans which mainly presented as thalamus edema with high T1 and T2 signals with partial enhancement. Mild hemorrage was also shown in one case. Acute or subacute onset with clinical manifestations of headache, hypomnesia and hypersomnia were reported in all cases. The neurological examination showed conscious disturbance, memory impairment and positive Babinski sign. The venous thrombi were formed mainly in the transverse and the straight sinuses in 3 cases with the deep cerebral venous involved in 2 cases. All patients were improved after the anticoagulation therapy. Dural arteriovenous fistula was found in the other case drained by the Rosenthal's vein, and the symptoms were ameliorated after the embolotherapy.

As the thalamus is drained by the thalamostriate vein and the lateral thalamic vein towards the internal cerebral vein with the caudate portion drained particularly by the Rosenthal's vein, venous thrombosis or fistula drainage into these veins would probably disturb the normal drainage of the thalamus and result in further edema and infarction. Thus, the venous infarction should be taken into consideration whenever bilateral thalamus lesions are encountered in clinical practice and DSA is necessary to confirm the diagnosis.