Imaging Sci Dent.  2016 Jun;46(2):141-144. 10.5624/isd.2016.46.2.141.

Evaluation of canalis basilaris medianus using cone-beam computed tomography

• Syed AZ
• Zahedpasha S
• Rathore SA
• Mupparapu

• KMID: 2308878
• DOI: http://doi.org/10.5624/isd.2016.46.2.141

Abstract

The aim of this report is to present two cases of canalis basilaris medianus as identified on cone-beam computed tomography (CBCT) in the base of the skull. The CBCT data sets were sent for radiographic consultation. In both cases, multi-planar views revealed an osseous defect in the base of the skull in the clivus region, the sagittal view showed a unilateral, well-defined, non-corticated, track-like low-attenuation osseous defect in the clivus. The appearance of the defect was highly reminiscent of a fracture of the clivus. The borders of osseous defect were smooth, and no other radiographic signs suggestive of osteolytic destructive processes were noted. Based on the overall radiographic examination, a radiographic impression of canalis basilaris medianus was made. Canalis basilaris medianus is a rare anatomical variant and is generally observed on the clivus. Due to its potential association with meningitis, it should be recognized and reported to avoid potential complications.

Keyword

Cone-Beam Computed Tomography; Skull Base; Anatomical Variation; CBM

MeSH Terms

Cone-Beam Computed Tomography*
Cranial Fossa, Posterior
Dataset
Meningitis
Skull
Skull Base

Figure

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  Fig. 1 Multiplanar reconstruction images demonstrate a defect on the basiocciput of the clivus consistent with canalis basilaris medianus in an 11-year-old female.

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  Fig. 2 A sagittal image demonstrates canalis basilaris medianus of the complete type on the superior aspect of the clivus.

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  Fig. 3 A schematic diagram depicting the different types of canalis basilaris medianus (CBM). The top row illustrates the complete forms of CBM and the bottom row illustrates incomplete forms of CBM. Top row: bifurcating type (left) CBM inferior type (middle), superior type (left), and. Bottom row: inferior recess (left), superior recess (middle), and channel (right). (Adapted from Currrano)

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