Morphometric analysis of dried skulls for optimization of transorbital approaches to middle cranial fossa: Anatomic insights for surgical planning

Introduction: The structures in the middle cranial fossa are challenging to assess due to complex placement and relations. Recent advances like transorbital approach offers a direct route to cranial targets via the orbit, reducing manipulation of neurovascular structures and improving postoperative outcomes. However, there is limited data on distances between orbital rim landmarks and key cranial structures. This study aims to provide critical quantitative data to support precise intracranial navigation. Materials and Methods: The study analyzed 43 human skulls of unknown age and sex. Linear distances from the superolateral angle and supraorbital notch of the orbital rim to key landmarks in the middle cranial fossa were measured using ImageJ software. Linear distance of important landmarks pertaining to transorbital approach from lateral orbital rim were recorded. Data was statistical analyzed using GraphPad Prima 8.0.2. Results: All the linear distances obtained between the key landmarks in middle cranial fossa like trigeminal fossa, foramen ovale, spinosum and rotundum; carotid sulcus upto supraorbital notch were less then those obtained from frontozygomatic suture. Bilaterally structures showed consistency (Student's t-test, p = 0.6624). Conclusions: This study provides precise, reproducible measurements that can guide surgeons in locating critical middle cranial landmarks for safe navigation into the orbital and cranial cavity during transorbital neuroendoscopic surgeries. These findings will be valuable for both anatomical education and neurosurgical practice. Keywords: Trigeminal fossa, Carotid sulcus, Foramen ovale, Foramen spinosum, Foramen rotundum, ImageJ