Anatomoradiological correlation of the intersection of the carotid siphon with the dura mater.

In order to obtain frames of reference to determine the place of intersection of the carotid siphon with the dura mater in conventional arteriograms, a debated topic lacking general agreement in the literature, 34 cadaveric sphenoids were prepared with the injection of radiopaque medium in both internal carotid arteries. After having marked the dura mater with steel wire, the pieces were radiographed in lateral view. The points of intersection of the clinoclinoid line and the sphenoidal line with the internal carotid artery as well as the emergence of the ophthalmic artery and its posterior projection were marked on the radiographs obtained. The distances between the various points were measured and submitted to statistical treatment. The results showed multiple regressions with a strong correlation coefficient in two equations. A table was built in which, knowing the distances between the points of the clinoclinoid and the sphenoidal plane lines and those of the ophthalmic artery and its projection, the position of the dura mater which covers the cavernous sinus may be estimated in arteriograms.