The superior anastomotic vein, also known as the vein of Trolard, is part of the superficial venous system of the brain. 

It should not be confused with the venous circle of Trolard, the anastomotic venous circle of the base of the brain which is the inconsistently found venous homologue of the better-known arterial circle of Willis.

Gross anatomy

It is the largest superficial vein on the lateral surface of the parietal or frontal lobe that connects the superior sagittal sinus and the superficial middle cerebral vein (of Sylvius). It usually runs in the post-central sulcus ¹ draining the adjacent cortex, but can be found in the central sulcus or anterior to it ⁵.

Its size is dictated by the relative size of the superficial middle cerebral vein and the inferior anastomotic vein of Labbé. The vein of Trolard is usually smaller than both of these. It has more variability than the vein of Labbé and is said to be the most variable of all the superficial veins of the brain ⁵.

As can be surmised by first principles, there is an inverse relationship between the size of the terminal Sylvian vein, the vein of Trolard, and the vein of Labbé, as all three share a similar drainage territory ³. Usually either the vein of Trolard or Labbé are dominant, both are small with the Sylvian vein being dominant or both are co-dominant with a small Sylvian vein. Occasionally the veins of Labbé and Trolard anastomose with themselves and bypass the Sylvain vein ⁵.

History and etymology

It is eponymously named after French surgeon and anatomist Jean Baptiste Paulin Trolard (1842–1910) who studied the anastomotic veins of the brain ³.

Trolard worked between France and Algeria and was an advocate of public vaccination in Algiers, establishing a vaccination institute alongside Louis Pasteur. He was also a strong critic of deforestation for which he created the League of Reforestation of Algeria ⁷.