Fossa of Waldeyer
The fossa of Waldeyer, also known as the mesentericoparietal fossa, is a congenital mesentery defect. It is found in about 1% of autopsy series and is formed due to non-fusion of the ascending mesocolon to the posterior parietal peritoneum.
The superior mesenteric artery runs along its (anterior) free edge.
History and etymology
It is named after Wilhelm von Waldeyer-Hartz, a German anatomist, also known for coining the term 'chromosome' and describing the tonsillar ring, which carries his name.