2025 Proffered Presentations
S337: SURGICAL ANATOMY OF THE SUPRAORBITAL AND MINIPTERIONAL APPROACHES: A STEPWISE COMPARATIVE STUDY
Fabio Torregrossa, MD; Alessandro De Bonis, MD; Amedeo Piazza, MD; Luciano Leonel, PhD; Megan Bauman, MS; Michael J. Link, MD, PhD; Giuseppe Lanzino, MD; Maria Peris-Celda, MD, PhD; Mayo Clinic, Rochester, MN (USA)
Introduction: "Minimally invasive" approaches have shown numerous potential advantages, such as less postoperative pain, preservation of brain parenchyma, shorter operative times, and better cosmetic results, including the supraorbital eyebrow (SE) and minipterional (MPT) approaches. This study aims to provide a high-quality, cadaver-based, operatively oriented resource comparing the supraorbital eyebrow (SE) and minipterional (MPT) approaches as corridors to the parasellar and interpeduncular regions.
Methods: Twelve formalin-fixed, latex-injected cadaveric specimens were used to perform bilateral SE and MPT approaches to the parasellar and interpeduncular regions. Dissections were documented in a stepwise fashion through high-resolution photographic and endoscopic image acquisition techniques. The surgical depths of each approach to 9 ipsilateral and contralateral landmarks were collected for quantitative purposes. A three-dimensional interactive cadaveric model generated through the photogrammetry scanning technique was described to highlight the anatomy of the two corridors (Fig. 1).
Results: Key steps described include positioning and skin incision, scalp dissection, craniotomy, flap elevation, durotomy, Sylvian spitting, arachnoid dissection, and their relevant landmarks (Fig. 2 & 3).
The SE and MPT approaches ensured access to the parasellar and interpeduncular regions through the subfrontal and transylvian corridors, respectively (Fig. 4).
A careful Sylvian fissure splitting should be performed to optimize the MPT's corridor while the SE offers direct access to the skull base. Compared to the SE, the MPT offered shorter operative depths to key landmarks, including the ipsi and contralateral anterior clinoid process, internal carotid artery, basilar tip, and interpeduncular fossa (p < .001). Although through a deeper corridor, the subfrontal route offers more direct access to the contralateral parasellar area and intepeduncular region.
Conclusion: "Minimally invasive" approaches to the central skull base are challenging to master yet represent foundational cranial surgical techniques. We present a comprehensive operatively oriented comparison that combines stepwise open and endoscopic cadaveric dissections with quantitative analysis for correct approach selection, mastery of relevant microsurgical anatomy, and enhanced familiarity for intraoperative decision-making.