The Cochlear Aqueduct as Anatomical Landmark in Endoscopic Lateral Skull Base Surgery

By June 10, 2019

Anschuetz, Lukas1; Molinari,Giulia2; Yacoub, Abraam1; Wimmer,Wilhelm1; Caversaccio, Marco1; Presutti, Livio2; Bonali,Marco2; Alicandri-Ciufelli, Matteo2
1 Department of Otorhinolaryngology, Head and Neck Surgery, Inselspital, Bern University Hospital, Bern, Swizerland.
2 Otolaryngology-Head and Neck Surgery Department, University Hospital of Modena

The aim of this study was to investigate the anatomy of the human cochlear acqueduct (CA) and its relationship with the internal auditory canal, by the help of 3D segmentation technology of micro-CT imaging. The endoscopic view of the CA was reported and described.

– Study Design: anatomical study on human CA
– Setting: tertiary referral centers
– Patients: human temporal bone cadaveric specimens;  3D segmentation of temporal bone computed tomography scans
– Intervention(s): none

– Main Outcome Measure(s): lenght of visual and virtual part of the CA, relationship to IAC lateral and medial parts, endoscopic view of CA during transcanal transpromontorial approach
Results: Dividing the CA in a virtual and a visual part, according to its appearance on CT images, the respective length of these parts were 6.6 mm (+- 1.7 mm) and 5.5 mm (+- 1.3 mm). Distance from CA to IAC was assessed. Pearson correlation between the visual part to lateral distance (-0.1375) or medial distance ( 0.0557) was not significant.
– Conclusion: This paper investigates the anatomy of the normal human CA and its relationship with the IAC during endoscopic transcanal transpromontorial approach. A better understanding of their anatomical relation would be relevant for otologist and neurosurgeons who deal with lateral skull base surgery and IAC/cerebello-pontine angle.