Morphological and Morphometric Analysis of Carotid Canal Apertures in the Nigerian Population

Abstract

Background: The external opening of the carotid canal (EOCC), the entry point of the internal carotid artery into the skull, varies across populations. This study characterized the EOCC with the mastoid process (shortest distance from the EOCC to the tip of the mastoid process [SDTCC]), the foramen magnum (shortest distance from the EOCC to the foramen magnum [SDFM]), and the midline of the skull base (shortest distance from the EOCC to the midline of the base of the skull [SDMCC]) in the Nigerian population. Materials and Methods: Fifty skull base pictures were taken in the plumed position with a digital camera. Measurements were taken using Image J software, and Euclidean distances were calculated. The shapes of the EOCC were noted. Paleontological Statistics (PAST 3.0) was used to perform descriptive statistics. Paired t-test and Pearson correlation were used to compare bilateral values and the relationship between the parameters, respectively. Results: The length (right, 0.53 [standard deviation (SD)=2.5] mm; left, 10.99 [SD=2.84] mm) and width (right, 13.96 [SD=2.43] mm; left, 14.16 [SD=2.09] mm) of the EOCC were recorded. In contrast to the populations in South Africa, Serbia, and India, the length of the EOCC obtained from this study is shorter than the breadth. The length of SDFM (right, 41.04 mm; left, 44.13 mm), SDMCC (right, 58.4 mm; left, 57.97 mm), and SDTCC (right, 57.29 mm; left, 55.61 mm) was established among Nigerians. Conclusion: The Nigerian population showed EOCC of shorter length than the breadth compared to other populations, and the size of the skull is independent of the foramina size. These dimensions may provide information for procedures that affect the skull base.

Keywords

• carotid canal
• mastoid process
• morphometric
• morphology
• skull base
• nigerians