CC BY-NC-ND 4.0 · Asian J Neurosurg 2024; 19(04): 791-804
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/)

Thieme Medical and Scientific Publishers Pvt. Ltd.
A-12, 2nd Floor, Sector 2, Noida-201301 UP, India

 
  • References

  • 1 Basma J, Anagnostopoulos C, Tudose A. et al. History, variations, and extensions of the retrosigmoid approach: anatomical and literature review. J Neurol Surg B Skull Base 2021; 83 (Suppl. 02) e324-e335
  • 2 Rodriguez Rubio R, Xie W, Vigo V. et al. Immersive surgical anatomy of the retrosigmoid approach. Cureus 2021; 13 (06) e16068
  • 3 Al-Sharshahi ZF, Hoz SS, Alrawi MA, Sabah MA, Albanaa SA, Moscote-Salazar LR. The use of non-living animals as simulation models for cranial neurosurgical procedures: a literature review. Chin Neurosurg J 2020; 6: 24
  • 4 Mantokoudis G, Huth ME, Weisstanner C. et al. Lamb temporal bone as a surgical training model of round window cochlear implant electrode insertion. Otol Neurotol 2016; 37 (01) 52-56
  • 5 Cordero A, del mar Medina M, Alonso A, Labatut T. Stapedectomy in sheep: an animal model for surgical training. Otol Neurotol 2011; 32 (05) 742-747
  • 6 Gocer C, Eryilmaz A, Genc U, Dagli M, Karabulut H, Iriz A. An alternative model for stapedectomy training in residency program: sheep cadaver ear. Eur Arch Otorhinolaryngol 2007; 264 (12) 1409-1412
  • 7 Hamamcioglu MK, Hicdonmez T, Tiryaki M, Cobanoglu S. A laboratory training model in fresh cadaveric sheep brain for microneurosurgical dissection of cranial nerves in posterior fossa. Br J Neurosurg 2008; 22 (06) 769-771
  • 8 Turan Suslu H, Ceylan D, Tatarlı N. et al. Laboratory training in the retrosigmoid approach using cadaveric silicone injected cow brain. Br J Neurosurg 2013; 27 (06) 812-814 Erratum in: Br J Neurosurg. 2014;28(6):823. Bahrı, Yasar [corrected to Bayrı, Yasar]
  • 9 Sudhakara Rao M, Chandrasekhara Rao K, Raja Lakshmi C, Satish Chandra T, Murthy PSN. Suitable alternative for human cadaver temporal bone dissection: comparative micro ear anatomy of cattle, pig and sheep with human. Indian J Otolaryngol Head Neck Surg 2019; 71 (04) 422-429
  • 10 Mallet C, Cornette R, Guadelli J. Morphometrical distinction between sheep (Ovis aries) and goat (Capra hircus) using the petrosal bone: application on French Protohistoric sites. Int J Osteoarchaeol 2019; 29 (04) 525-537
  • 11 Irugu DV, Singh AC, Sikka K, Bhinyaram J, Sharma SC. Establishing a temporal bone laboratory in teaching institutes to train future otorhinolaryngologists and fundamentals of temporal bone laboratory: considerations and requirements. Indian J Otolaryngol Head Neck Surg 2016; 68 (04) 451-455
  • 12 Mowry SE, Woodson E, Gubbels S, Carfrae M, Hansen MR. A simple assessment tool for evaluation of cadaveric temporal bone dissection. Laryngoscope 2018; 128 (02) 451-455
  • 13 Frithioff A, Frendø M, Pedersen DB, Sørensen MS, Wuyts Andersen SA. 3D-printed models for temporal bone surgical training: a systematic review. Otolaryngol Head Neck Surg 2021; 165 (05) 617-625
  • 14 Frithioff A, Frendø M, Weiss K. et al. Effect of 3D-printed models on cadaveric dissection in temporal bone training. OTO Open 2021; 5 (04) X211065012
  • 15 Okada DM, de Sousa AM, Huertas RdeA, Suzuki FA. Surgical simulator for temporal bone dissection training. Braz J Otorhinolaryngol 2010; 76 (05) 575-578
  • 16 Alvernia JE, Pradilla G, Mertens P, Lanzino G, Tamargo RJ. Latex injection of cadaver heads: technical note. Neurosurgery 2010; 67 (2, suppl operative): 362-367
  • 17 Sanan A, Abdel Aziz KM, Janjua RM, van Loveren HR, Keller JT. Colored silicone injection for use in neurosurgical dissections: anatomic technical note. Neurosurgery 1999; 45 (05) 1267-1271 , discussion 1271–1274
  • 18 Tatagiba M, Roser F, Schuhmann MU, Ebner FH. Vestibular schwannoma surgery via the retrosigmoid transmeatal approach. Acta Neurochir (Wien) 2014; 156 (02) 421-425 , discussion 425
  • 19 Matsushima K, Kohno M, Komune N, Miki K, Matsushima T, Rhoton Jr AL. Suprajugular extension of the retrosigmoid approach: microsurgical anatomy. J Neurosurg 2014; 121 (02) 397-407
  • 20 Alimohamadi M, Samii M. Suprajugular extension of the retrosigmoid approach. J Neurosurg 2014; 121 (03) 764-765
  • 21 Constanzo F, Gerhardt J, Ramina R. How I do it: retrosigmoid suprajugular approach to the jugular foramen. Acta Neurochir (Wien) 2019; 161 (11) 2271-2274
  • 22 Colasanti R, Tailor AR, Zhang J, Ammirati M. Functional petrosectomy via a suboccipital retrosigmoid approach: guidelines and topography. World Neurosurg 2016; 87: 143-154
  • 23 Day JD, Kellogg JX, Fukushima T, Giannotta SL. Microsurgical anatomy of the inner surface of the petrous bone: neuroradiological and morphometric analysis as an adjunct to the retrosigmoid transmeatal approach. Neurosurgery 1994; 34 (06) 1003-1008
  • 24 Scerrati A, Lee JS, Zhang J, Ammirati M. Exposing the fundus of the internal acoustic meatus without entering the labyrinth using a retrosigmoid approach: is it possible?. World Neurosurg 2016; 91: 357-364
  • 25 Scerrati A, Lee JS, Zhang J, Ammirati M. Microsurgical anatomy of the internal acoustic meatus as seen using the retrosigmoid approach. Otol Neurotol 2016; 37 (05) 568-573
  • 26 Cueva RA, Chole RA. Maximizing exposure of the internal auditory canal via the retrosigmoid approach: an anatomical, radiological, and surgical study. Otol Neurotol 2018; 39 (07) 916-921
  • 27 Miller RS, Pensak ML. An anatomic and radiologic evaluation of access to the lateral internal auditory canal via the retrosigmoid approach and description of an internal labyrinthectomy. Otol Neurotol 2006; 27 (05) 697-704
  • 28 Savardekar A, Nagata T, Kiatsoontorn K. et al. Preservation of labyrinthine structures while drilling the posterior wall of the internal auditory canal in surgery of vestibular schwannomas via the retrosigmoid suboccipital approach. World Neurosurg 2014; 82 (3-4): 474-479
  • 29 Wanibuchi M, Fukushima T, Friedman AH. et al. Hearing preservation surgery for vestibular schwannomas via the retrosigmoid transmeatal approach: surgical tips. Neurosurg Rev 2014; 37 (03) 431-444 , discussion 444
  • 30 Matsushima K, Kohno M, Nakajima N. Hearing preservation in vestibular schwannoma surgery via retrosigmoid transmeatal approach. Acta Neurochir (Wien) 2019; 161 (11) 2265-2269
  • 31 Jia C, Xu C, Wang M, Chen J. How to precisely open the internal auditory canal for resection of vestibular schwannoma via the retrosigmoid approach. Front Surg 2022; 9: 889402
  • 32 Seoane E, Rhoton Jr AL. Suprameatal extension of the retrosigmoid approach: microsurgical anatomy. Neurosurgery 1999; 44 (03) 553-560
  • 33 Chanda A, Nanda A. Retrosigmoid intradural suprameatal approach: advantages and disadvantages from an anatomical perspective. Neurosurgery 2006; 59 (1, suppl 1): ONS1-ONS6 , discussion ONS1–ONS6
  • 34 Samii M, Tatagiba M, Carvalho GA. Retrosigmoid intradural suprameatal approach to Meckel's cave and the middle fossa: surgical technique and outcome. J Neurosurg 2000; 92 (02) 235-241
  • 35 Ishi Y, Terasaka S, Motegi H. Retrosigmoid intradural suprameatal approach for petroclival meningioma. J Neurol Surg B Skull Base 2019; 80 (Suppl. 03) S296-S297
  • 36 Xu Y, Hendricks BK, Nunez MA, Mohyeldin A, Fernandez-Miranda JC, Cohen-Gadol AA. Microsurgical anatomy of the endoscopy-assisted retrosigmoid intradural suprameatal approach to the Meckel's cave. Oper Neurosurg (Hagerstown) 2021; 21 (02) 41-47
  • 37 Samii M, Metwali H, Samii A, Gerganov V. Retrosigmoid intradural inframeatal approach: indications and technique. Neurosurgery 2013; 73 (1, suppl Operative): ons53-ons59 , discussion ons60
  • 38 Colasanti R, Tailor AR, Gorjian M, Zhang J, Ammirati M. Microsurgical and endoscopic anatomy of the extended retrosigmoid inframeatal infratemporal approach. Neurosurgery 2015; 11 (Suppl. 02) 181-189 , discussion 189
  • 39 Sato Y, Mizutani T, Shimizu K, Freund HJ, Samii M. Retrosigmoid intradural suprameatal-inframeatal approach for complete surgical removal of a giant recurrent vestibular schwannoma with severe petrous bone involvement: technical case report. World Neurosurg 2018; 110: 93-98
  • 40 Meling TR, Zegarek G, Schaller K. How I do it: retrosigmoid intradural inframeatal petrosectomy. Acta Neurochir (Wien) 2021; 163 (03) 649-653
  • 41 Matsushima K, Kohno M, Nakajima N. et al. Retrosigmoid intradural suprajugular approach to jugular foramen tumors with intraforaminal extension: surgical series of 19 cases. World Neurosurg 2019; 125: e984-e991
  • 42 Constanzo F, Coelho Neto M, Nogueira GF, Ramina R. Microsurgical anatomy of the jugular foramen applied to surgery of glomus jugulare via craniocervical approach. Front Surg 2020; 7: 27
  • 43 Jun W, Gao YL, Yu HG. et al. Comparison of translabyrinthine and retrosigmoid approach for treating vestibular schwannoma: a meta-analysis. Clin Neurol Neurosurg 2020; 196: 105994
  • 44 Kim KH, Cho YS, Seol HJ. et al. Comparison between retrosigmoid and translabyrinthine approaches for large vestibular schwannoma: focus on cerebellar injury and morbidities. Neurosurg Rev 2021; 44 (01) 351-361
  • 45 Irving RM, Jackler RK, Pitts LH. Hearing preservation in patients undergoing vestibular schwannoma surgery: comparison of middle fossa and retrosigmoid approaches. J Neurosurg 1998; 88 (05) 840-845
  • 46 Ammirati M, Ma J, Cheatham ML, Maxwell D, Bloch J, Becker DP. Drilling the posterior wall of the petrous pyramid: a microneurosurgical anatomical study. J Neurosurg 1993; 78 (03) 452-455
  • 47 Pillai P, Sammet S, Ammirati M. Image-guided, endoscopic-assisted drilling and exposure of the whole length of the internal auditory canal and its fundus with preservation of the integrity of the labyrinth using a retrosigmoid approach: a laboratory investigation. Neurosurgery 2009; 65 (06) 53-59 , discussion 59
  • 48 Matsushima K, Komune N, Matsuo S, Kohno M. Microsurgical and endoscopic anatomy for intradural temporal bone drilling and applications of the electromagnetic navigation system: various extensions of the retrosigmoid approach. World Neurosurg 2017; 103: 620-630
  • 49 Bernardo A, Boeris D, Evins AI, Anichini G, Stieg PE. A combined dual-port endoscope-assisted pre- and retrosigmoid approach to the cerebellopontine angle: an extensive anatomo-surgical study. Neurosurg Rev 2014; 37 (04) 597-608
  • 50 Takemura Y, Inoue T, Morishita T, Rhoton Jr AL. Comparison of microscopic and endoscopic approaches to the cerebellopontine angle. World Neurosurg 2014; 82 (3-4): 427-441