Foramen of vesalius.

OBJECTIVE To investigate the frequency of unilateral or bilateral foramen of Vesalius (FV), number of FV present on one side, and presence of a septum on FV. METHODS We bilaterally examined, 347 sphenoid bones of collections of the Department of Anatomy, Istanbul Faculty of Medicine, Istanbul University, Istanbul and Dokuz Eylul Faculty of Medicine, Izmir, Turkey in 2007. RESULTS Of the 347 bilaterally examined skulls, 87 (25.1%) had bilateral FV, 191 (55%) specimens did not have any FV on both sides, and 69 specimens (19.9%) had unilateral FV (33 skulls had FV on the right side, and the remaining 36 skulls had FV on the left. Of the 156 skulls which had FV, only 4 skulls 3 on the right, one on the left) had double FV on the same side. We have not observed any specimens which had 3 or more FV on the same side. Of the 156 skulls which had FV, 11 skulls had a septum on FV, 3 skulls had a septum on FV on the right side, and 6 skulls had a septum on FV on the left side. Two skulls bilaterally had a septum on both sides. CONCLUSION We believe that our data about FV will be enlightening not only for anatomists, but also for clinicians.