title: Anatomical nuances of the internal carotid artery in relation to the quadrangular space.
abstract: OBJECTIVE The aim of this study was to evaluate the anatomical variations of the internal carotid artery (ICA) in relation to the quadrangular space (QS) and to propose a classification system based on the results. METHODS A total of 44 human cadaveric specimens were dissected endonasally under direct endoscopic visualization. During the dissection, the anatomical variations of the ICA and their relationship with the QS were noted. RESULTS The space between the paraclival ICAs (i.e., intercarotid space) can be classified as 1 of 3 different shapes (i.e., trapezoid, square, or hourglass) based on the trajectory of the ICAs. The ICA trajectories also directly influence the volumetric area of the QS. Based on its geometry, the QS was classified as one of the following: 1) Type A has the smallest QS area and is associated with a trapezoid intercarotid space, 2) Type B corresponds to the expected QS area (not minimized or enlarged) and is associated with a square intercarotid space, and 3) Type C has the largest QS area and is associated with an hourglass intercarotid space. CONCLUSIONS The different trajectories of the ICAs can modify the area of the QS and may be an essential parameter to consider for preoperative planning and defining the most appropriate corridor to reach Meckel's cave. In addition, ICA trajectories should be considered prior to surgery to avoid injuring the vessels.
authors.affiliation: Departments of1Otolaryngology-Head & Neck Surgery and.|3Department of Otolaryngology-Head & Neck Surgery, Santa Casa de Misericórida de São Paulo,Brazil.
authors.forename: Ricardo L L
authors.initials: RLL
authors.lastname: Dolci
authors.affiliation: 2Neurosurgery, Wexner Medical Center at The Ohio State University, Columbus, Ohio; and.
authors.forename: Leo F S
authors.initials: LFS
authors.lastname: Ditzel Filho
authors.affiliation: 2Neurosurgery, Wexner Medical Center at The Ohio State University, Columbus, Ohio; and.
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Goulart
authors.affiliation: Departments of1Otolaryngology-Head & Neck Surgery and.
authors.forename: Smita
authors.initials: S
authors.lastname: Upadhyay
authors.affiliation: Departments of1Otolaryngology-Head & Neck Surgery and.
authors.forename: Lamia
authors.initials: L
authors.lastname: Buohliqah
authors.affiliation: 3Department of Otolaryngology-Head & Neck Surgery, Santa Casa de Misericórida de São Paulo,Brazil.
authors.forename: Paulo R
authors.initials: PR
authors.lastname: Lazarini
authors.affiliation: Departments of1Otolaryngology-Head & Neck Surgery and.|2Neurosurgery, Wexner Medical Center at The Ohio State University, Columbus, Ohio; and.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Prevedello
authors.affiliation: Departments of1Otolaryngology-Head & Neck Surgery and.|2Neurosurgery, Wexner Medical Center at The Ohio State University, Columbus, Ohio; and.
authors.forename: Ricardo L
authors.initials: RL
authors.lastname: Carrau
mesh_terms: D002343:Carotid Artery, Internal / Q000033:anatomy & histology*; D006801:Humans
keywords: CN = cranial nerve; CSF = cerebrospinal fluid; EEA = endoscopic endonasal approach; ICA = internal carotid artery; Meckel's cave; QS = quadrangular space; anatomy; cavernous sinus; endonasal; endoscopic; internal carotid artery; quadrangular space; skull base