CC BY-NC-ND 4.0 · Asian J Neurosurg
DOI: 10.1055/s-0044-1790517
Case Report

Sheep Head Cadaveric Model for the Transmeatal Extensions of the Retrosigmoid Approach

1   Department of Neurosurgery, National Children Medical Center, Universidade Federal de Sao Paulo, Sao Paulo, Brazil
2   National Children's Medical Center, Tashkent Uzbekistan
,
3   Department of Neurosurgery, Federal University of Sao Paulo, Sao Paulo, Brazil
,
Arevik Abramyan
4   Department of Neurosurgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, United States
,
Feres Eduardo Aparecido Chaddad Neto
3   Department of Neurosurgery, Federal University of Sao Paulo, Sao Paulo, Brazil
› Author Affiliations

Abstract

The transmeatal extension of the retrosigmoid approach is an important procedure used in the treatment of various pathologies affecting the posterior fossa, petroclival region, and jugular foramen. Mastering this technique requires a high level of manual skill, particularly in temporal bone drilling. The objective of this study was to describe an easily accessible and cost-effective model of the transmeatal extension of the retrosigmoid approach using cadaveric sheep heads. Five cadaveric sheep heads, fixed in alcohol and formalin with intravascular-colored silicone injection, were prepared for this study. Two heads (four sides) were designated for illustrative anatomical specimens, while three heads (six sides) were used for surgical simulation. Additionally, one head was used to prepare and dissect a dry skull. All critical steps of the transmeatal approach, including both supra- and inframeatal extensions, were successfully replicated on the model. A comparative anatomical analysis was conducted, focusing on the technical nuances of the model. The cadaveric sheep head serves as an effective model for the retrosigmoid approach with transmeatal extensions, primarily for training manual haptic skills. While the sheep model cannot precisely replicate human anatomy, it still offers valuable training opportunities for neurosurgeons, particularly when human cadaveric specimens are unavailable.



Publication History

Article published online:
17 September 2024

© 2024. Asian Congress of Neurological Surgeons. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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