{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T20:39:59Z","timestamp":1784320799934,"version":"3.55.0"},"reference-count":28,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,23]],"date-time":"2025-01-23T00:00:00Z","timestamp":1737590400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Background: Different lateral and postero-lateral cranial approaches to the petroclival region and to the mid-upper brain stem have been described so far, some of which require extensive osseous demolition and possible damage of neurovascular structures. Neuronavigational systems are now extensively available for preoperative planning and intraoperative navigation to assist the surgeons in choosing the optimally invasive approach for each pathology. Herein, we describe a detailed navigation-augmented morphometric analysis to bring insight into the usefulness of an anterior petrosectomy (AP) to handle lesions in the petroclival region. Methods: Eight cadaveric, silicone injected heads were used. A total of 14 approaches (AP, n = 8; retrosigmoid, RS, n = 6) using a standard microsurgical dissection technique were performed. All specimens had preoperative CT and MRI scans, as well as a post-dissection CT. The neuronavigational system was used for distance measurements, craniotomy sizes and surgical corridor volumes, for each approach. Results: The distance from the skull surface to the petrous apex was significantly shorter in the AP approach when compared with the RS (46.0 \u00b1 1.9 mm versus 71.3 \u00b1 1.8 mm, respectively, p &lt; 0.001). Although the craniotomy size was not different, the volume of the surgical corridor was significantly larger with the AP approach (21.31 \u00b1 1.91 cm3 vs. 13.39 \u00b1 1.8 cm3). The AP approach increased the length of the basilar artery exposure from 6.9 \u00b1 1.5 mm (obtained with a standard subtemporal approach) to 22.1 \u00b1 1.7 mm (p &lt; 0.0001). Conclusions: The surgical corridor to the petroclival region achieved by virtue of an AP was significantly larger and featured shorter working distances, resulting in a higher degree of surgical freedom. Although significant individual anatomical variations of fundamental neurovascular and bony structures were found, these difficulties were overcome by careful pre- and intraoperative use of neuronavigation.<\/jats:p>","DOI":"10.3390\/brainsci15020104","type":"journal-article","created":{"date-parts":[[2025,1,23]],"date-time":"2025-01-23T04:54:31Z","timestamp":1737608071000},"page":"104","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Anterior Petrosectomy vs. Retrosigmoid Approach\u2014Surgical Anatomy and Navigation-Augmented Morphometric Analysis: A Comparative Study in Cadaveric Laboratory Setting"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8086-1622","authenticated-orcid":false,"given":"Stefano","family":"Signoretti","sequence":"first","affiliation":[{"name":"Division of Neurosurgery, Department of Head & Neck Surgery, S. Eugenio\/CTO Hospital, ASL Roma 2, 00144 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8431-0433","authenticated-orcid":false,"given":"Francesco","family":"Signorelli","sequence":"additional","affiliation":[{"name":"Institute of Neurosurgery, Fondazione Policlinico Universitario A. Gemelli IRCCS, Catholic University, 00153 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alessandro","family":"Pesce","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Delitala","sequence":"additional","affiliation":[{"name":"Division of Neurosurgery, San Carlo di Nancy Hospital, 00165 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1087-0491","authenticated-orcid":false,"given":"Massimiliano","family":"Visocchi","sequence":"additional","affiliation":[{"name":"Institute of Neurosurgery, Fondazione Policlinico Universitario A. Gemelli IRCCS, Catholic University, 00153 Rome, Italy"},{"name":"Research Center and Master II Degree Surgical Approaches Craniovertebral Junction, Fondazione Policlinico Universitario A. Gemelli IRCCS, Catholic University, 00153 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"133","DOI":"10.2302\/kjm.44.133","article-title":"Light up the \u201cno-man\u2019s land\u201d on the brain stem","volume":"44","author":"Kawase","year":"1995","journal-title":"Keio J. Med."},{"key":"ref_2","unstructured":"Samii, M., and Knosp, E. (2012). Approaches to the Clivus: Approaches to No Man\u2019s Land, Springer Science & Business Media."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"282","DOI":"10.1016\/j.clineuro.2015.10.032","article-title":"Anterior petrosal approach: The safety of Kawase triangle as an anatomical landmark for anterior petrosectomy in petroclival meningiomas","volume":"139","author":"Tomio","year":"2015","journal-title":"Clin. Neurol. Neurosurg."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1161","DOI":"10.1007\/s00701-011-1010-9","article-title":"How I do it: Epidural anterior petrosectomy","volume":"153","author":"Roche","year":"2011","journal-title":"Acta Neurochir."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1656","DOI":"10.1016\/j.jocn.2011.03.027","article-title":"The retrosigmoid approach to petroclival meningioma surgery","volume":"18","author":"Chen","year":"2011","journal-title":"J. Clin. Neurosci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/S0967-5868(99)90598-2","article-title":"Resection of large petroclival meningiomas by the simple retrosigmoid route","volume":"6","author":"Samii","year":"1999","journal-title":"J. Clin. Neurosci."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"857","DOI":"10.3171\/jns.1985.63.6.0857","article-title":"Transpetrosal approach for aneurysms of the lower basilar artery","volume":"63","author":"Kawase","year":"1985","journal-title":"J. Neurosurg."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1055\/s-0034-1543971","article-title":"Anterior petrosectomy: Consecutive series of 46 patients with attention to approach-related complications","volume":"76","author":"Alikhani","year":"2015","journal-title":"J. Neurol. Surg. Part B Skull Base"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"457","DOI":"10.3171\/jns.1965.23.5.0457","article-title":"Surgical treatment of ruptured aneurysms of the basilar artery: Experience with 14 cases","volume":"23","author":"Drake","year":"1965","journal-title":"J. Neurosurg."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"410","DOI":"10.3109\/00016487509121344","article-title":"An extended approach through the middle cranial fossa to the internal auditory meatus and the cerebello-pontine angle","volume":"80","author":"Bochenek","year":"1975","journal-title":"Acta Oto-Laryngol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"869","DOI":"10.1227\/00006123-199106000-00014","article-title":"Anterior transpetrosal-transtentorial approach for sphenopetroclival meningiomas: Surgical method and results in 10 patients","volume":"28","author":"Kawase","year":"1991","journal-title":"Neurosurgery"},{"key":"ref_12","first-page":"546","article-title":"Surgical management of petroclival meningiomas: Defining resection goals based on risk of neurological morbidity and tumor recurrence rates in 137 patients","volume":"56","author":"Little","year":"2005","journal-title":"Neurosurgery"},{"key":"ref_13","first-page":"466","article-title":"Retrosigmoid Transtentorial Approach Compared to Traditional Transpetrosal Approaches for the Resection of Petroclival Meningiomas: A Case-Control Study","volume":"82","author":"Jha","year":"2020","journal-title":"J. Neurol. Surg. B Skull Base."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"564","DOI":"10.1016\/j.wneu.2020.04.058","article-title":"A 360\u00b0 Approach to the Craniovertebral Junction in a Cadaveric Laboratory Setting: Historical Insights, Current, and Future Perspectives in a Comparative Study","volume":"140","author":"Signorelli","year":"2020","journal-title":"World Neurosurg."},{"key":"ref_15","first-page":"243","article-title":"Combined Transoral Exoscope and OARM-Assisted Approach for Craniovertebral Junction Surgery. New Trends in an Old-Fashioned Approach","volume":"Volume 135","author":"Visocchi","year":"2023","journal-title":"The Funnel: From the Skull Base to the Sacrum: New Trends, Technologies and Strategies"},{"key":"ref_16","first-page":"1009","article-title":"Microanatomical study of the extradural middle fossa approach to the petroclival and posterior cavernous sinus region: Description of the rhomboid construct","volume":"34","author":"Day","year":"1994","journal-title":"Neurosurgery"},{"key":"ref_17","first-page":"167","article-title":"Surgery of the petrous bone (middle ear). Tumors and pseudotumors","volume":"1","author":"Stennert","year":"1988","journal-title":"Archives of Oto-Rhino-Laryngol. Suppl."},{"key":"ref_18","first-page":"238","article-title":"Morphometric analysis of bone resection in anterior petrosectomies","volume":"77","author":"Ahmed","year":"2016","journal-title":"J. Neurol. Surg. Part B Skull Base"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"280","DOI":"10.4103\/2277-4025.298227","article-title":"Morphometry relevant to anterior petrosectomy with special reference to Kawase\u2019s triangle","volume":"6","author":"Siddiqui","year":"2017","journal-title":"Natl. J. Clin. Anat."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"e405","DOI":"10.1016\/j.wneu.2020.02.127","article-title":"Extended anterior petrosectomy through the transcranial middle fossa approach and extended endoscopic transphenoidal-transclival approaches: Qualitative and quantitative anatomic analysis","volume":"138","author":"Hasanbelliu","year":"2020","journal-title":"World Neurosurg."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1055\/s-2007-991117","article-title":"The middle cranial fossa: Morphometric study and surgical considerations","volume":"17","author":"Maina","year":"2007","journal-title":"Skull Base."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1055\/s-0033-1356491","article-title":"Volumetry and analysis of anatomical variants of the anterior portion of the petrous apex outlined by the Kawase triangle using computed tomography","volume":"75","author":"Isolan","year":"2014","journal-title":"J. Neurol. Surg. B Skull Base"},{"key":"ref_23","first-page":"1","article-title":"The middle fossa transpetrous approach to the anterior-superior cerebellopontine angle","volume":"7","author":"House","year":"1986","journal-title":"Otol. Neurotol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"130","DOI":"10.1055\/s-2008-1060575","article-title":"The middle fossa transpetrous approach for petroclival meningiomas","volume":"3","author":"Hitselberger","year":"1993","journal-title":"Skull Base Surg."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"ons192","DOI":"10.1227\/NEU.0b013e31823583a1","article-title":"The middle fossa approach and extended middle fossa approach: Technique and operative nuances","volume":"70","author":"Day","year":"2012","journal-title":"Oper. Neurosurg."},{"key":"ref_26","first-page":"P004","article-title":"Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Translabyrinthine, Transotic, and Transcochlear Approaches","volume":"84","author":"Alexander","year":"2023","journal-title":"J. Neurol. Surg. Part B Skull Base"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"E14","DOI":"10.3171\/2012.6.FOCUS12163","article-title":"Surgery for vestibular schwannomas: A systematic review of complications by approach","volume":"33","author":"Ansari","year":"2012","journal-title":"Neurosurg. Focus"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Shibao, S., Yoshida, K., Sasao, R., and Nishimoto, M. (2024). Prevention of Cerebrospinal Fluid Leakage in the Anterior Transpetrosal Approach. J. Clin. Med., 13.","DOI":"10.3390\/jcm13061718"}],"container-title":["Brain Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-3425\/15\/2\/104\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,8]],"date-time":"2025-10-08T10:34:03Z","timestamp":1759919643000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-3425\/15\/2\/104"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,23]]},"references-count":28,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["brainsci15020104"],"URL":"https:\/\/doi.org\/10.3390\/brainsci15020104","relation":{},"ISSN":["2076-3425"],"issn-type":[{"value":"2076-3425","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,1,23]]}}}