Objective: The purpose of this study is to determine internal carotid artery exposure in an
endoscopic endonasal approach compared with internal carotid artery exposure with
a progressive anterior transfacial dissection.
Study Design: Anatomic, morphometric analysis of human cadaver heads.
Setting: Anatomy laboratory
Participants: Latex injected adult cadaver heads.
Main outcome measures: Internal carotid segments and length above the bifurcation were measured with an
endoscopic approach, a superstructure maxillary swing (palate in native position),
a complete maxillary swing with palatal split, and an anterior mandibular swing. Anatomic
limits to the carotid space were compared with each approach.
Results: An endoscopic approach allowed visualization of 2cm on average of ICA at 4.4cm on
average above carotid bifurcation. A superior swing approach allowed visualization
of 3cm on average of ICA at 3.4cm on average above carotid bifurcation. A total maxillary
swing approach allowed visualization of 4.5cm on average of ICA at 1.9 cm on average
above carotid bifurcation. A mandibulotomy approach allowed visualization of 6.4cm
on average of ICA at 0cm on average above carotid bifurcation.
Conclusions: The complexity of surgical procedures involving the skull base relates in part to
the close relationship to neurovascular structures including the internal carotid
artery. Internal carotid artery exposure in head and neck surgery can be important
from a patient safety standpoint to ensure proximal and distal control to minimize
bleeding complications. Anatomic limits can also be important if the ICA has neoplastic
involvement that needs to be surgically addressed. The ICA in the parapharyngeal space
can be difficult to dissect via an endoscopic approach given its lateral position
in the coronal plane. The endoscopic approach showed the smallest portion of the ICA
at the furthest point from the bifurcation suggesting the least amount of exposure.
We were able to expose an additional centimeter with a superior swing technique, and
another 2.5 cm with a superior maxillary swing. The mandibulotomy exposed the entire
internal carotid artery and the bifurcation. When choosing between endoscopic, superior
maxillary swing, and complete maxillary swing, the surgeon can consider the degree
of exposure they need and where exactly in the skull base they need access to.
