The radiological anatomy of clivus for surgical approaches

Abstract

Objectives: Clivus is the central part of the skull base that extends from the anterior part of the foramen magnum to the posterior clinoid process. Clivus has close relationships with crucial neurovascular structures. The purpose of the study was to evaluate the anatomical relationships at the clival region on computed tomography (CT) images for to provide data to conduct best pathways and safe zones for clival surgeries. Methods: Brain and cervical CT images of 103 patients (48 female, 55 male; mean age: 63) were examined retrospectively. The length of the clivus at the sagittal plane, the width of the inferior and middle parts of the clivus at the midsagittal plane, and the distance between the internal carotid arteries at the sagittal plane in axial sections were measured. Results: The mean length of the clivus at the sagittal plane was 38.40±5.82 mm. The mean width of the inferior and middle parts of the clivus at the midsagittal plane was 6.67±1.45 mm and 10.32±1.66 mm, respectively. In axial sections, the mean distance between the internal carotid arteries was 22.10±03.42 mm in the sagittal plane. Conclusion: Knowing the dimensions of the clivus and the distance between the internal carotid arteries at the sagittal plane is important for a safe and successful clival surgery.

Keywords

• clivus
• computed tomography
• skull base

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