MRI venous architecture of the thalamus

Our purpose is to describe the thalamic veins using a novel approach named venous gliography in cases with primary or secondary gliomas of the thalamus. Venous gliography is defined by authors as a method to visualize veins on MRI Brain T1-weighted post contrast scans containing gliomas which have induced regional venous congestion.

Routine clinical MR Imaging studies were reviewed to assess the presence of thalamic veins in 29 glioma cases. In addition, confocal reconstruction techniques (Anatom-e and Osirix) were used in cases that had thin sections (1.0-1.5mm) post contrast T1 weighted sequences. Multiplanar MIP and confocal volume rendered images were generated to evaluate the thalamic veins in those cases.

Using venous gliography and confocal reconstruction techniques, two patterns in the venous architecture of the thalamus were documented. First, the branching pattern created by the tributaries of the internal cerebral vein, namely the superior thalamic vein and the anterior thalamic vein, which together formed the superior group of thalamic veins. Second, the pattern created by the un-branched vertically oriented veins, namely the inferior thalamic veins and the posterior thalamic veins, which joined the basal vein of Rosenthal and constituted the inferior group of thalamic veins.

Venous gliography combined with the use of confocal reconstruction techniques provided a novel approach to display the thalamic veins that are usually not seen. The understanding of the venous architecture is mandated by the recent research where veins have taken on an important role in the perivenular spread of gliomas.