Cranio-spinal Neurosurgical Approaches

Official title

Cranio-spinal Neurosurgical Approaches: Qualitative and Quantitative Analysis and Validation of New Minimally Invasive Methods on Cadaveric Anatomical Models.

Overview

The goal of this observational study is to learn how different cranio-spinal surgical approaches work and how much anatomical exposure each technique provides in donated human cadaver specimens. The study also aims to understand anatomical variations and to evaluate new surgical techniques and tools that may improve neurosurgical training and practice. The main questions it aims to answer are: * How much surgical exposure area and volume of work does each cranio-spinal approach allow? * How do anatomical variations influence the effectiveness and feasibility of different approaches? Researchers will also compare results obtained using different surgical visualization methods (such as the surgical microscope approach or macroscopic evaluation) to see if any method improves visibility or operative efficiency. Cadaveric specimens will undergo: * Step-by-step cranio-spinal surgical approaches performed by trained neurosurgeons. * Quantitative measurements of exposed anatomical areas using imaging software (BrainChop). * Assessment of operative time, perceived difficulty by surgeons, and visibility of target anatomical structures. * Testing of new surgical instruments or techniques when applicable, without involving any drugs or medical devices. This study follows Italian regulations on post-mortem body donation for scientific research (Law No. 10/2020) and is conducted at a single research center recognized as an IRCCS (Istituto di Ricovero e Cura a Carattere Scientifico-Scientific Institute for Hospitalization and Care).

Detailed description

This observational, monocentric, preclinical study. The main objective of this study is to conduct a systematic and quantitative preclinical analysis of multiple cranio-spinal surgical approaches, using both macroscopic and microscopic evaluation.

The study evaluates multiple surgical corridors to the cranial and spinal regions and involves detailed measurement of the volume of work and exposed anatomical area attainable with each approach. Additional technical objectives include the analysis of anatomical variations that may influence surgical execution, and the validation of new surgical techniques and instruments in a controlled laboratory environment.

All dissections will be carried out on cadaveric specimens voluntarily donated according to Italian legislation on post-mortem body donation (Law No. 10/2020). Procedures will be performed by trained neurosurgeons using standard microsurgical techniques. Quantitative measurements of exposure areas and operative volumes will be obtained using dedicated imaging software, including BrainChop.

The study also incorporates structured evaluations of technical difficulty and surgeon experience. After completing each approach, operating surgeons will provide standardized ratings of perceived difficulty, visibility of target structures, and usability of any new surgical tools or techniques tested. These assessments contribute to the systematic validation of surgical methods and instrumentation in the preclinical setting.

In addition, the study supports surgical education by integrating structured dissection sessions. Participants (surgeons or trainees) will complete pre- and post-training assessments to evaluate procedural understanding, anatomical knowledge, and perceived skill acquisition.

The study will enroll 35 cadaveric specimens over a three-year period. No drugs or implantable medical devices will be used. All specimens will be stored and handled according to institutional anatomical laboratory standards.

The statistical analysis plan includes descriptive and comparative analyses. Quantitative variables-such as exposure area, volume of work, and operative time-will be summarized as mean ± standard deviation (SD). Qualitative variables-such as visibility scores or difficulty ratings-will be reported as absolute and relative frequencies. For pre- and post-training comparisons, the paired t-test or Wilcoxon signed-rank test will be applied depending on data distribution. Comparisons of operative time or exposure metrics across techniques will be performed using Analysis of Variance (ANOVA) or the Kruskal-Wallis test. Statistical significance will be defined as p \< 0.05. All analyses will be conducted using Stata statistical software (StataCorp LLC, College Station, TX, USA).

Interventions

• Procedure Standardized cranio-spinal neurosurgical approaches performed on donated cadaveric specimens to assess surgical exposure, feasibility, anatomical variation, and selected new techniques.
  This intervention consists of performing standardized cranio-spinal neurosurgical approaches on donated human cadaveric specimens to evaluate surgical exposure, operative feasibility, and anatomical variation in a preclinical setting. The procedures use both macroscopic and microscopic visualization systems. uantitative measurements of exposure area and operative workspace are obtained through dedicated imaging and navigation-based software. The intervention also allows controlled testing of new

Primary outcome measures

• Quantification of Work Volume and Exposed Area in Cranio-Spinal Surgical Approaches [Time frame: Measurements will be obtained twice for each approach on every specimen: before the dissection using baseline CT imaging and after completing the approach using repeat CT imaging on the same day.]
• Exposed Anatomical Surface Area Obtained by Each Surgical Approach [Time frame: Measurements will be obtained twice for each approach on every specimen: before the dissection using baseline CT imaging and after completing the approach using repeat CT imaging on the same day.]

Eligibility criteria

Inclusion criteria

• Cadaveric specimens from individuals who provided informed consent for post-mortem donation of their body or tissues for scientific research.
• Specimens that meet all legal requirements for anatomical donation under Italian Law No. 10/2020 and Presidential Decree (DPR) No. 47/2023.
• Specimens that are available for the full duration of the study and suitable for performing multiple cranio-spinal surgical approaches.

Exclusion criteria

• Specimens that do not meet the legal or ethical requirements for anatomical donation as defined by Italian regulations.
• Cadavers with major anatomical deformities, advanced tissue degradation, or pathological conditions that would interfere with surgical dissection or measurement accuracy.
• Specimens lacking adequate documentation or verified donor consent for post-mortem donation.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Observational model

Case-only

Study locations

Center list to be confirmed — check the primary protocol.

Publications

• Schreiber A, Ferrari M, Rampinelli V, Doglietto F, Belotti F, Lancini D, Ravanelli M, Rodella LF, Fontanella MM, Nicolai P. Modular Endoscopic Medial Maxillectomies: Quantitative Analysis of Surgical Exposure in a Preclinical Setting. World Neurosurg. 2017 Apr;100:44-55. doi: 10.1016/j.wneu.2016.12.094. Epub 2017 Jan 3. PMID 28057590
• Muhanna N, Chan H, Qiu J, Daly M, Khan T, Doglietto F, Kucharczyk W, Goldstein DP, Irish JC, de Almeida JR. Volumetric Analysis of Endoscopic and Maxillary Swing Surgical Approaches for Nasopharyngectomy. J Neurol Surg B Skull Base. 2018 Oct;79(5):466-474. doi: 10.1055/s-0037-1617432. Epub 2018 Jan 19. PMID 30210974
• Jagersberg M, Brodard J, Qiu J, Mansouri A, Doglietto F, Gentili F, Kucharczyk W, Fasel J, Schaller K, Radovanovic I. Quantification of Working Volumes, Exposure, and Target-Specific Maneuverability of the Pterional Craniotomy and Its Minimally Invasive Variants. World Neurosurg. 2017 May;101:710-717.e2. doi: 10.1016/j.wneu.2017.02.011. Epub 2017 Feb 22. PMID 28254536
• Ferrari M, Schreiber A, Mattavelli D, Lombardi D, Rampinelli V, Doglietto F, Rodella LF, Nicolai P. Surgical anatomy of the parapharyngeal space: Multiperspective, quantification-based study. Head Neck. 2019 Mar;41(3):642-656. doi: 10.1002/hed.25378. Epub 2018 Dec 28. PMID 30592348
• Ebner FH, Koerbel A, Kirschniak A, Roser F, Kaminsky J, Tatagiba M. Endoscope-assisted retrosigmoid intradural suprameatal approach to the middle fossa: anatomical and surgical considerations. Eur J Surg Oncol. 2007 Feb;33(1):109-13. doi: 10.1016/j.ejso.2006.09.036. Epub 2006 Nov 14. PMID 17110074
• Doglietto F, Belotti F, Qiu J, Roca E, Radovanovic I, Agur A, Kucharczyk W, Schreiber A, Villaret AB, Nicolai P, Gentili F, Fontanella MM. Endonasal and Transoral Approaches to the Craniovertebral Junction: A Quantitative Anatomical Study. Acta Neurochir Suppl. 2019;125:37-44. doi: 10.1007/978-3-319-62515-7_6. PMID 30610300
• Doglietto F, Qiu J, Ravichandiran M, Radovanovic I, Belotti F, Agur A, Zadeh G, Fontanella MM, Kucharczyk W, Gentili F. Quantitative comparison of cranial approaches in the anatomy laboratory: A neuronavigation based research method. World J Methodol. 2017 Dec 26;7(4):139-147. doi: 10.5662/wjm.v7.i4.139. eCollection 2017 Dec 26. PMID 29354486
• Agosti E, De Maria L, Mattogno PP, Della Pepa GM, D'Onofrio GF, Fiorindi A, Lauretti L, Olivi A, Fontanella MM, Doglietto F. Quantitative Anatomical Studies in Neurosurgery: A Systematic and Critical Review of Research Methods. Life (Basel). 2023 Aug 28;13(9):1822. doi: 10.3390/life13091822. PMID 37763226

Identifiers

NCT: NCT07287462 · 7155

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗