Anterior Commissure

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Why I like Anterior Commissure? It is a horizontal stripe of tissue connecting hemispheres that is located below frontal horns and anterior and superior to the third ventricle.
It is very thin in antero-posterior dimension and very distinct on coronal images. Above two coronal 1.4mm thick T1 contrast enhanced images look identical but are from different examinations of the same patient. Anterior Commissure is helpful in synchronizing those two sequences for comparison e.g. in tumor growth.
I also love anatomy drawings. The above is Figure 744 from Henry Gray (1825–1861). Anatomy of the Human Body. 1918. Courtesy Bartleby.com 

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