Incidence of anomalous canals in the base of the skull: a retrospective radio-anatomical study using cone-beam computed tomography.

PURPOSE: Several skull-base foramina including foramen meningo-orbitale, craniopharyngeal canals, canaliculus innominatus, foramen vesalius, palatovaginal canals, and canalis basalis medianus are visible on cone-beam computed tomographs. A good understanding of the anatomical variants of these foramina is important to accurately diagnose fractures, understand the paths that infections may take, and identify associated anomalies. We used cone-beam computed tomography to measure the incidences of skull-base foramen variants in a normal population.

METHODS

A total of 350 subjects (200 females, 150 males, 6-30 years of age) were included. The prevalences of foramen meningo-orbitale, craniopharyngeal canals, canaliculus innominatus, foramina vesalius, palatovaginal canals, and canalis basalis medianus were evaluated by age and gender.

RESULTS

Subject age ranged from 6 to 30 years (mean age ± SD = 15.1 ± 4.08). Foramen meningo-orbitale, craniopharyngeal canals, canaliculus innominatus, foramen vesalius, palatovaginal canal, and canalis basalis medianus were observed in 51 (14.6%), 19 (5.4%), 60 (17.1%), 145 (41.1%), 34 (9.7%), and 15 (4.3%) patients, respectively.

CONCLUSIONS

Skull-base foramina are important clinically and radiologically. Imaging of such variants via cone-beam computed tomography is valuable for both physicians and patients. Few studies of skull-base foramina have used cone-beam computed tomography. Additional research is required for a fuller understanding of this phenomenon.