Measurement accuracy of foramen of vesalius for safe percutaneous techniques using computer-assisted three-dimensional landmarks.

The presence and description of anatomical findings about the foramen of Vesalius (FV) is important in the surgical procedure on the trigeminal nerve and/or trigeminal ganglion. This is an evaluation area for percutaneous techniques. A morphological analysis of the FVs was made in a total of 344 sides of the basis cranii of adult skulls by computerized photogrammetry using standardized digital photographs. The FV was identified in 60 specimens (34.8%). The FV was observed to be present bilaterally in 16 specimens (9.3%). The incidence of unilateral FV was 25.5% of the skulls, of which in 26 specimens (15.1%) it occurred on the left side, and in 18 specimens (10.4%) on the right side. The FV was observed to present a double opening in two specimens. The diameters of the FV were found to be 0.86 ± 0.21 (right) and 1.07 ± 0.37 mm (left). The incidence of openings with a diameter of FV 0.5 mm or more was found to be 45%. The area of the FV was calculated as 1.09 ± 0.51, and 1.4 ± 0.83 mm(2) on the right and the left, respectively. The mean distances of FV to the foramen ovale were measured as 2.30 ± 1.14 mm (right) and 2.46 ± 0.89 mm (left). The mean distances of FV to foramen spinosum were found to be 10.76 ± 1.26 mm (right) and 10.42 ± 1.29 mm (left). The findings suggest that the diameter of FV as <0.5 mm was safer to work with, while the opening types bigger than 0.5 mm opening types were highly risky for percutaneous techniques on the foramen ovale. In our study, a clear standardization has been achieved. The findings were the data obtained through computer-assisted three dimensional landmarks, appropriate for use in three dimensional planning.