Cranio-spinal Neurosurgical Approaches

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).