Prevalence and morphometric features of fossa navicularis on cone beam computed tomography in Turkish population

The objective of this study is to determine the prevalence and morphometric features of fossa navicularis, a close radiographic anatomic variation of canalis basilaris medianus of the basiocciput, in a Turkish population, using cone beam computed tomography (CBCT).

The study group consisted of 723 patients (female: 420, male: 303) having CBCT scans. The patients had no syndromes, history of neurological diseases or surgery in the area of interest. On the images that revealed a fossa navicularis, the depth, length, and width measurements were performed, and were compared to the age and gender of the patients. The shape and number of fossa navicularis were also recorded.

Fossa navicularis was identified in 48 (6.6%) patients. Among these patients, 19 were female (4.5% of all female patients), whereas 29 were male (9.6% of all male patients), and their age ranged between 10 and 68 years (mean age: 34.0 ± 18.7). No significant difference was found between genders and age groups in terms of depth, length, and width measurements (p > 0.05). In 39 (5.4%) patients, fossa navicularis presented oval in shape.

Even though the prevalence of fossa navicularis was found to be higher than previously reported, it still seems to be rare. Anatomical structure of the fossa navicularis can be studied effectively on CBCT images.