Dorello's Canal or Abducens Nerve Canal: Constancy or Inconstancy?

Dorello's canal is an eponym term referring to a small fibro osseous landmark, by way of arc, located at the apex of the petrous temporal region and for which the nerve abducens passes before reaching the cavernous sinus. This landmark is not referenced in Terminologia Anatomica, even as a variable structure. We selected 74 adult dry skulls and six heads fixed in formalin 10 % without classifying them by ethnicity or gender. As inclusion criteria, we selected those where the middle cranial fossa and the apex of the petrous temporal region were in good condition. Fifty seven (57) skulls (83, 82 %) showed the presence of canal bilaterally; 4 (5.89 %) showed it unilaterally to the right; 4 (5,89 %) were unilaterally at the left and 3 (4,41 %) had no canal. The results of this study indicate that this bone landmark is present in most of the skulls, even bilaterally. Since it is not referenced in the Terminologia Anatomica, we propose the term canal abducens nerve to avoid using the eponymous term Dorello's canal.