A Morphometric Analysis for the Feasibility of Percutaneous Translacerum Access of the Internal Carotid Artery Based on Computed Tomography Angiography

Background: The increasing frequency of elderly patients with severe tortuous anatomy, especially when combined with fibromuscular dysplasia, can make intracranial canalization severely difficult or impossible. Computed tomography angiography was used to determine the feasibility of accessing the internal carotid artery (ICA) via a percutaneous translacerum approach. Methods: Twenty consecutive stroke activations with CT angiography were reconstructed in three-dimensional models to take measurements to assess if currently available technologies could safely provide access. We assessed the diameter of the foramen lacerum and ICA. Entry points and angulations were measured based on trajectory. Our trajectory was based on anatomic observations that provided a safe corridor from the angle of the jaw to the foramen lacerum. Results: Based on the 40 carotid arteries from 20 patients, 77.5% had a large enough foramen lacerum to provide access to the ICA. Although there were no traversals of the pharynx, we noted a 20% traversal of the eustachian tube and 5% traversal of a small maxillary artery branch. There was no large-vessel traversal by the trajectory. All patients with bilateral stenotic foramen lacerum were African-American women; 44% of African-American women had bilateral stenotic foramen lacerum. The diameter of the ICA and foramen lacerum would not be prohibitive of sheath placement in patients without stenosis with adequate canalized length of sheath necessary for stability. Conclusions: Access of the ICA via the foramen lacerum can be safely performed with currently available technologies.