Measurement of One Intrathalamic Point Represented by the Superior Thalamic Vein and Its Clinical Significance

A few veins within the thalamus are regarded as growing prior to the formation of some nuclei or fibre tracts of the region. Thereby, from the earlier stage of the development, these veins must be imprinted on a map of the thalamus with more or less distortion. Browning (1884), Schlesinger (1939) and Padget (1956) found out one vein passing the superior region of the thalamus, of which Padget described an earlier growth within the thalamus (“as late as 40 mm” of an embryo) and a drainage system upto the internal cerebral vein. In the recent investigation Giudicelli and Salamon (1970) classified veins of the thalamus into four groups according to their supply and pointed out that the superior thalamic vein arises from the anterior superior portion of the thalamus. which seems to be the same as the “thalamic (anterior nuclear) vein” of Padget. This vein when observed on the lateral film of the vertebral angiography is very easily identified as it makes a dot-like contrast due to its transverse course in the superior region of the thalamus. The dot-like contrast we label as “point L” appears to be located at a regular distance from the anterior end of the thalamus.