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DOI: 10.1055/a-2114-4660
Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Endoscopic Endonasal Middle-Inferior Clivectomy, Odontoidectomy, and Far-Medial Approach
Funding This work was supported in part by Joseph I. and Barbara Ashkins Endowed Professorship in Neurosurgery and by Charles B. and Ann L. Johnson Endowed Professorship in Neurosurgery.![](https://www.thieme-connect.de/media/jnlsb/202405/lookinside/thumbnails/10-1055-a-2114-4660_23feb0037-1.jpg)
Abstract
Introduction The clival, paraclival, and craniocervical junction regions are challenging surgical targets. To approach these areas, endoscopic endonasal transclival approaches (EETCAs) and their extensions (far-medial approach and odontoidectomy) have gained popularity as they obviate manipulating and working between neurovascular structures. Although several cadaveric studies have further refined these contemporary approaches, few provide a detailed step-by-step description. Thus, we aim to didactically describe the steps of the EETCAs and their extensions for trainees.
Methods Six formalin-fixed cadaveric head specimens were dissected. All specimens were latex-injected using a six-vessel technique. Endoscopic endonasal middle and inferior clivectomies, far-medial approaches, and odontoidectomy were performed.
Results Using angled endoscopes and surgical instruments, an endoscopic endonasal midclivectomy and partial inferior clivectomy were performed without nasopharyngeal tissue disruption. To complete the inferior clivectomy, far-medial approach, and partially remove the anterior arch of C1 and odontoid process, anteroinferior transposition of the Eustachian–nasopharynx complex was required by transecting pterygosphenoidal fissure tissue, but incision in the nasopharynx was not necessary. Full exposure of the craniocervical junction necessitated bilateral sharp incision and additional inferior mobilization of the posterior nasopharynx. Unobstructed access to neurovascular anatomy of the ventral posterior fossa and craniocervical junction was provided.
Conclusion EETCAs are a powerful tool for the skull-base surgeon as they offer a direct corridor to the ventral posterior fossa and craniocervical junction unobstructed by eloquent neurovasculature. To facilitate easier understanding of the EETCAs and their extensions for trainees, we described the anatomy and surgical nuances in a didactic and step-by-step fashion.
Keywords
skull base surgery - middle and inferior clivectomies - odontoidectomy - far-medial approach - foramen lacerum - pterygosphenoidal fissureEthical Approval
This retrospective chart review study involving human participants was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. The Human Investigation Committee (IRB) of the Mayo Clinic approved this study.
Publication History
Received: 26 February 2023
Accepted: 19 June 2023
Accepted Manuscript online:
21 June 2023
Article published online:
02 August 2023
© 2023. Thieme. All rights reserved.
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References
- 1 Kim YH, Jeon C, Se Y-B. et al. Clinical outcomes of an endoscopic transclival and transpetrosal approach for primary skull base malignancies involving the clivus. J Neurosurg 2018; 128 (05) 1454-1462
- 2 Shkarubo AN, Koval' KV, Dobrovol'skiy GF. et al. Extended endoscopic endonasal posterior (transclival) approach to tumors of the clival region and ventral posterior cranial fossa. Part 1. Topographic and anatomical features of the clivus and adjacent structures [in Russian]. Vopr Neirokhir 2017; 81 (04) 5-16
- 3 Rhoton Jr AL. The cerebellopontine angle and posterior fossa cranial nerves by the retrosigmoid approach. Neurosurgery 2000; 47 (03) S93-S129
- 4 Al-Mefty O, Kadri PAS, Hasan DM, Isolan GR, Pravdenkova S. Anterior clivectomy: surgical technique and clinical applications. J Neurosurg 2008; 109 (05) 783-793
- 5 Fernandez-Miranda JC, Gardner PA, Snyderman CH. et al. Clival chordomas: a pathological, surgical, and radiotherapeutic review. Head Neck 2014; 36 (06) 892-906
- 6 Kassam AB, Gardner P, Snyderman C, Mintz A, Carrau R. Expanded endonasal approach: fully endoscopic, completely transnasal approach to the middle third of the clivus, petrous bone, middle cranial fossa, and infratemporal fossa. Neurosurg Focus 2005; 19 (01) E6
- 7 Bossi Todeschini A, Montaser AS, Hardesty DA, Carrau RL, Prevedello DM. The limits of the endoscopic endonasal transclival approach for posterior fossa tumors. J Neurosurg Sci 2018; 62 (03) 322-331
- 8 Frank G, Sciarretta V, Calbucci F, Farneti G, Mazzatenta D, Pasquini E. The endoscopic transnasal transsphenoidal approach for the treatment of cranial base chordomas and chondrosarcomas. Neurosurgery 2006; 59 (1, Suppl 1): ONS50-ONS57 , discussion ONS50–ONS57
- 9 Shkarubo AN, Koval' KV, Dobrovol'skiy GF. et al. Extended endoscopic endonasal posterior (transclival) approach to tumors of the clival region and ventral posterior cranial fossa. Part 2. Topographic and anatomical aspects and surgical technique [in Russian]. Vopr Neirokhir 2017; 81 (05) 17-30
- 10 Shkarubo AN, Koval KV, Shkarubo MA, Chernov IV, Andreev DN, Panteleyev AA. Endoscopic endonasal transclival approach to tumors of the clivus and anterior region of the posterior cranial fossa: an anatomic study. World Neurosurg 2018; 119: e825-e841
- 11 Shkarubo AN, Koval KV, Chernov IV, Andreev DN, Kurnosov AB, Panteleyev AA. Endoscopic endonasal transclival removal of tumors of the clivus and anterior region of the posterior cranial fossa (results of surgical treatment of 140 patients). Chin Neurosurg J 2018; 4: 36
- 12 Oostra A, van Furth W, Georgalas C. Extended endoscopic endonasal skull base surgery: from the sella to the anterior and posterior cranial fossa. ANZ J Surg 2012; 82 (03) 122-130
- 13 Messina A, Bruno MC, Decq P. et al. Pure endoscopic endonasal odontoidectomy: anatomical study. Neurosurg Rev 2007; 30 (03) 189-194 , discussion 194
- 14 Simal-Julián JA, Miranda-Lloret P, Beltrán-Giner A, Plaza-Ramirez E, Botella-Asunción C. Full endoscopic endonasal extreme far-medial approach: Eustachian tube transposition. J Neurosurg Pediatr 2013; 11 (05) 584-590
- 15 Zoli M, Mazzatenta D, Valluzzi A, Mascari C, Pasquini E, Frank G. Endoscopic endonasal odontoidectomy. Neurosurg Clin N Am 2015; 26 (03) 427-436
- 16 Komune N, Matsuo S, Miki K. et al. Surgical anatomy of the eustachian tube for endoscopic transnasal skull base surgery: a cadaveric and radiologic study. World Neurosurg 2018; 112: e172-e181
- 17 Leonel LCP, Carlstrom LP, Graffeo CS. et al. Foundations of advanced neuroanatomy: technical guidelines for specimen preparation, dissection, and 3D-photodocumentation in a surgical anatomy laboratory. J Neurol Surg B Skull Base 2021; 82 (Suppl. 03) e248-e258
- 18 Pinheiro-Neto CD, Snyderman CH. Nasoseptal flap. Adv Otorhinolaryngol 2013; 74: 42-55
- 19 Wang WH, Lieber S, Mathias RN. et al. The foramen lacerum: surgical anatomy and relevance for endoscopic endonasal approaches. J Neurosurg 2018; 1: 1-12
- 20 Ozturk K, Snyderman CH, Gardner PA, Fernandez-Miranda JC. The anatomical relationship between the eustachian tube and petrous internal carotid artery. Laryngoscope 2012; 122 (12) 2658-2662
- 21 Liu J, Pinheiro-Neto CD, Fernandez-Miranda JC. et al. Eustachian tube and internal carotid artery in skull base surgery: an anatomical study. Laryngoscope 2014; 124 (12) 2655-2664
- 22 Pinheiro-Neto CD, Salgado-Lopez L, Leonel LCPC, Aydin SO, Peris-Celda M. Endoscopic endonasal approaches to the clivus with no violation of the nasopharynx: surgical anatomy and clinical illustration. J Neurol Surg B Skull Base 2021; 83 (Suppl. 02) e374-e379
- 23 Keshelava G, Mikadze I, Abzianidze G, Kikalishvili L, Kakabadze Z. Surgical anatomy of petrous part of the internal carotid artery. Neuroanat 2000; 8: 46-48
- 24 Pinheiro-Neto CD, Fernandez-Miranda JC, Rivera-Serrano CM. et al. Endoscopic anatomy of the palatovaginal canal (palatosphenoidal canal): a landmark for dissection of the vidian nerve during endonasal transpterygoid approaches. Laryngoscope 2012; 122 (01) 6-12
- 25 Matsuno H, Rhoton Jr AL, Peace D. Microsurgical anatomy of the posterior fossa cisterns. Neurosurgery 1988; 23 (01) 58-80
- 26 McDavid LJ, Khan YS. Anatomy, Head and Neck, Prevertebral Muscles. Treasure Island, FL: StatPearls Publishing; 2022
- 27 Belotti F, Tengattini F, Mattavelli D. et al. Transclival approaches for intradural pathologies: historical overview and present scenario. Neurosurg Rev 2021; 44 (01) 279-287
- 28 Little RE, Taylor RJ, Miller JD. et al. Endoscopic endonasal transclival approaches: case series and outcomes for different clival regions. J Neurol Surg B Skull Base 2014; 75 (04) 247-254
- 29 Zenonos G, Alkhalili K, Koutourousiou M. et al. Endoscopic endonasal approach for clival chordomas: 12 years of experience from a large skull base referral center. J Neurol Surg Part B Skull Base 2016; 77-A007
- 30 Ormond D, Wise S, Oyesiku N, Patel A, Hadjipanayis C. Endoscopic endonasal resection of clival chordomas: a case series. J Neurol Surg B Skull Base 2013; 73: 226-232
- 31 Shkarubo AN, Koval' KV, Kadashev BA, Andreev DN, Chernov IV. Extended endoscopic endonasal posterior (transclival) approach to tumors of the clival region and ventral posterior cranial fossa. Part 3. Analysis of surgical treatment outcomes in 127 patients [in Russian]. Vopr Neirokhir 2018; 82 (03) 15-28
- 32 Zoli M, Milanese L, Bonfatti R. et al. Clival chordomas: considerations after 16 years of endoscopic endonasal surgery. J Neurosurg 2018; 128 (02) 329-338
- 33 Cavallo LM, Mazzatenta D, D'Avella E. et al. The management of clival chordomas: an Italian multicentric study. J Neurosurg 2020; 135 (01) 93-102
- 34 Marigil M, Almeida JP, Karekezi C, de Almeida JR, Gentili F. Expanded endoscopic endonasal approach for resection of intradural chordoma: surgical and anatomic nuances: 2-dimensional operative video. Oper Neurosurg (Hagerstown) 2019; 17 (02) E66
- 35 Dehdashti AR, Karabatsou K, Ganna A, Witterick I, Gentili F. Expanded endoscopic endonasal approach for treatment of clival chordomas: early results in 12 patients. Neurosurgery 2008; 63 (02) 299-307 , discussion 307–309
- 36 Fraser JF, Nyquist GG, Moore N, Anand VK, Schwartz TH. Endoscopic endonasal transclival resection of chordomas: operative technique, clinical outcome, and review of the literature. J Neurosurg 2010; 112 (05) 1061-1069
- 37 Fatemi N, Dusick JR, Gorgulho AA. et al. Endonasal microscopic removal of clival chordomas. Surg Neurol 2008; 69 (04) 331-338
- 38 Stippler M, Gardner PA, Snyderman CH, Carrau RL, Prevedello DM, Kassam AB. Endoscopic endonasal approach for clival chordomas. Neurosurgery 2009; 64 (02) 268-277 , discussion 277–278
- 39 Saito K, Toda M, Tomita T, Ogawa K, Yoshida K. Surgical results of an endoscopic endonasal approach for clival chordomas. Acta Neurochir (Wien) 2012; 154 (05) 879-886
- 40 Yousaf J, Afshari FT, Ahmed SK, Chavda SV, Sanghera P, Paluzzi A. Endoscopic endonasal surgery for Clival Chordomas - a single institution experience and short term outcomes. Br J Neurosurg 2019; 33 (04) 388-393
- 41 Rahme RJ, Arnaout OM, Sanusi OR, Kesavabhotla K, Chandler JP. Endoscopic approach to clival chordomas: the northwestern experience. World Neurosurg 2018; 110: e231-e238
- 42 Snyderman CH, Gardner PA. Current opinion in otolaryngology and head and neck surgery: clival chordoma and its management. Curr Opin Otolaryngol Head Neck Surg 2020; 28 (02) 118-121
- 43 Beer-Furlan A, Vellutini EAS, Balsalobre L, Stamm AC. Endoscopic endonasal approach to ventral posterior fossa meningiomas: from case selection to surgical management. Neurosurg Clin N Am 2015; 26 (03) 413-426
- 44 Jean WC, Felbaum DR, Anaizi A, DeKlotz TR. Endoscopic endonasal approach for transclival resection of a petroclival meningioma: a technical note. Cureus 2016; 8 (06) e641
- 45 Heiferman DM, Somasundaram A, Alvarado AJ, Zanation AM, Pittman AL, Germanwala AV. The endonasal approach for treatment of cerebral aneurysms: a critical review of the literature. Clin Neurol Neurosurg 2015; 134: 91-97
- 46 Meybodi AT, Benet A, Vigo V. et al. Assessment of the endoscopic endonasal approach to the basilar apex region for aneurysm clipping. J Neurosurg 2019; 1306: 1937-1948
- 47 Dong X, Wang X, Shao A, Zhang J, Hong Y. Endoscopic endonasal transclival approach to ventral pontine cavernous malformation: case report. Front Surg 2021; 8: 654837
- 48 Erickson N, Siu A, Sherman JH, Gragnaniello C, Singh A, Litvack Z. Endoscopic transnasal transclival approach to a pontine cavernoma with associated developmental venous anomaly. World Neurosurg 2018; 118: 212-218
- 49 Gómez-Amador JL, Ortega-Porcayo LA, Palacios-Ortíz IJ, Perdomo-Pantoja A, Nares-López FE, Vega-Alarcón A. Endoscopic endonasal transclival resection of a ventral pontine cavernous malformation: technical case report. J Neurosurg 2017; 127 (03) 553-558
- 50 Sanborn M, Storm P, Adappa N, Palmer J, Newman J, Lee J. Endoscopic, transnasal, transclival resection of a pontine cavernoma. J Neurol Surg B Skull Base 2012; 118: 212-218
- 51 Linsler S, Oertel J. Endoscopic endonasal transclival resection of a brainstem cavernoma: a detailed account of our technique and comparison with the literature. World Neurosurg 2015; 84 (06) 2064-2071
- 52 Zhao B, Wei YK, Li GL. et al. Extended transsphenoidal approach for pituitary adenomas invading the anterior cranial base, cavernous sinus, and clivus: a single-center experience with 126 consecutive cases. J Neurosurg 2010; 112 (01) 108-117
- 53 Liu JK, Patel J, Goldstein IM, Eloy JA. Endoscopic endonasal transclival transodontoid approach for ventral decompression of the craniovertebral junction: operative technique and nuances. Neurosurg Focus 2015; 38 (04) E17
- 54 Labib MA, Belykh E, Cavallo C. et al. The endoscopic endonasal eustachian tube anterolateral mobilization strategy: minimizing the cost of the extreme-medial approach. J Neurosurg 2020; 134 (03) 831-842
- 55 Fernandez-Miranda JC, Morera VA, Snyderman CH, Gardner P. Endoscopic endonasal transclival approach to the jugular tubercle. Neurosurgery 2012; 71 (1, Suppl Operative): 146-158 , discussion 158–159
- 56 Karadag A, Kirgiz PG, Bozkurt B. et al. The benefits of inferolateral transtubercular route on intradural surgical exposure using the endoscopic endonasal transclival approach. Acta Neurochir (Wien) 2021; 163 (08) 2141-2154
- 57 Vaz-Guimaraes Filho F, Wang EW, Snyderman CH, Gardner PA, Fernandez-Miranda JC. Endoscopic endonasal “far-medial” transclival approach: Surgical anatomy and technique. Oper Tech Otolaryngol–Head Neck Surg 2013; 162: 597-603
- 58 Sella and beyond: approaches to the clivus and posterior fossa, petrous apex, and cavernous sinus. In: Rhinology and Skull Base Surgery. 2014 ; Thieme Medical Publishers. 758–771
- 59 Kamat A, Lee JYK, Goldstein GH. et al. Reconstructive challenges in the extended endoscopic transclival approach. J Laryngol Otol 2015; 129 (05) 468-472
- 60 Simal-Julian JA, Pérez de San Román-Mena L, Sanchis-Martín MR, Quiroz-Tejada A, Miranda-Lloret P, Botella-Asunción C. Septal rhinopharyngeal flap: a novel technique for skull base reconstruction after endoscopic endonasal clivectomies. J Neurosurg 2021; 136 (06) 1601-1606
- 61 Iacoangeli M, Di Rienzo A, di Somma LGM. et al. Improving the endoscopic endonasal transclival approach: the importance of a precise layer by layer reconstruction. Br J Neurosurg 2014; 28 (02) 241-246
- 62 Pashaev B, Danilov V, Vagapova G. et al. Failure of skull base defects reconstruction after endonasal surgery. complications, treatment options and outcomes. J Neurol Surg Part B Skull Base 2016
- 63 Zwagerman NT, Wang EW, Shin SS. et al. Does lumbar drainage reduce postoperative cerebrospinal fluid leak after endoscopic endonasal skull base surgery? A prospective, randomized controlled trial. J Neurosurg 2018; 131 (04) 1172-1178