TY - JOUR
T1 - Surgical Anatomy of the Eustachian Tube for Endoscopic Transnasal Skull Base Surgery
T2 - A Cadaveric and Radiologic Study
AU - Komune, Noritaka
AU - Matsuo, Satoshi
AU - Miki, Koichi
AU - Akagi, Yojiro
AU - Kurogi, Ryota
AU - Iihara, Koji
AU - Nakagawa, Takashi
N1 - Publisher Copyright:
© 2018 Elsevier Inc.
PY - 2018/4
Y1 - 2018/4
N2 - Objective: The endoscopic endonasal approach to the anatomically complex lateral skull base presents technical challenges. The use of the eustachian tube as a landmark to identify the petrous internal carotid artery has recently been reported, and this study aims to define the anatomic relationship between the eustachian tube and its surrounding structures using cadaveric dissection and radiologic analysis. Methods: To clarify the relationship of the eustachian tube with its surrounding structures, we performed endoscopic and microscopic dissection of 4 adult cadaveric heads and analyzed computed topography scans from 20 patients. Results: The eustachian tube is divided into the osseous and cartilaginous parts. The cartilaginous part can be further subdivided into the posterolateral, middle, and anteromedial parts, based on its relationship to the skull base. The eustachian tube is closely related to the pterygoid process of the sphenoid bone, the foramen lacerum, and the petrosal apex and is directed away from the oblique sagittal plane almost parallel to the vidian canal at 12.2° ± 6.2° (mean ± standard deviation). The relationship between the course of the vidian canal and the eustachian tube can aid the estimation of the anatomic course of the horizontal segment of the petrous carotid artery. Conclusions: The eustachian tube is a useful landmark for predicting the course of the internal carotid artery when accessing the lateral skull base regions via an endonasal route. A profound understanding of the relationship between the eustachian tube and the surrounding skull base structures is important for endoscopic endonasal skull base surgeries.
AB - Objective: The endoscopic endonasal approach to the anatomically complex lateral skull base presents technical challenges. The use of the eustachian tube as a landmark to identify the petrous internal carotid artery has recently been reported, and this study aims to define the anatomic relationship between the eustachian tube and its surrounding structures using cadaveric dissection and radiologic analysis. Methods: To clarify the relationship of the eustachian tube with its surrounding structures, we performed endoscopic and microscopic dissection of 4 adult cadaveric heads and analyzed computed topography scans from 20 patients. Results: The eustachian tube is divided into the osseous and cartilaginous parts. The cartilaginous part can be further subdivided into the posterolateral, middle, and anteromedial parts, based on its relationship to the skull base. The eustachian tube is closely related to the pterygoid process of the sphenoid bone, the foramen lacerum, and the petrosal apex and is directed away from the oblique sagittal plane almost parallel to the vidian canal at 12.2° ± 6.2° (mean ± standard deviation). The relationship between the course of the vidian canal and the eustachian tube can aid the estimation of the anatomic course of the horizontal segment of the petrous carotid artery. Conclusions: The eustachian tube is a useful landmark for predicting the course of the internal carotid artery when accessing the lateral skull base regions via an endonasal route. A profound understanding of the relationship between the eustachian tube and the surrounding skull base structures is important for endoscopic endonasal skull base surgeries.
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U2 - 10.1016/j.wneu.2018.01.003
DO - 10.1016/j.wneu.2018.01.003
M3 - Article
C2 - 29325963
AN - SCOPUS:85041593288
SN - 1878-8750
VL - 112
SP - e172-e181
JO - World Neurosurgery
JF - World Neurosurgery
ER -