2026 Poster Presentations
P091: WHAT WE HAVE LEARNT FROM QUANTITIVATIVE MEASUREMENTS AND MORPHOMETRIC ANALYSIS OF ANTERIOR, POSTERIOR AND COMBINED PETROSECTOMIES: SYSTEMIC REVIEW OF CADAVERIC STUDIES
Tessa Allen; Mehdi Khaleghi, MD; Garrett Dyess; Asa Barnett; Jai Thakur, MD; University of South Alabama
Introduction: Complex middle fossa and posterior fossa skull base pathologies often require drilling various aspects of the petrous bone to maximize the surgical corridor and increase exposure. In the past few decades, there have arisen many nuanced approaches to perform a petrosectomy through different corridors, and multiple clinical and cadaveric studies have highlighted the results. No previous study has focused on a quantitative analysis of cadaveric studies on these approaches.
Method: This study analyzed published morphometric cadaveric studies on the distinct cuts of the petrous bone to expand on visualization and access to deep anatomical structures. Databases of PubMed, Scopus and Web of Science were explored following PRISMA guidelines for published cadaveric studies on anterior, posterior, and combined petrosectomies between 2000 and 2025. Quantitative studies assessing at least of the following: surgical exposure (AOE), angle of attack (AOA), and surgical freedom (SF) were included. Initial search yielded 283 results; thereafter, deduplication and primary refinement based on title and abstract screening included 46 studies. Secondary refinement based on full text for comparable studies yielded 12 eligible studies for systematic review. Results from the review were summarized based on approach type and subcategories of characteristics of angle of attack, surgical freedom, and area of exposure.
Results: A total of 78 wet cadaveric heads and 117 sides were dissected over the 12 studies, with 98 heads undergoing anterior (37 with Kawase approach or ATPA, 9 ETOA, 5 ETOA+ORR, 27 variations of EEA, 5 TMF, 5 EETT, 10 TOEA), 4 heads undergoing posterior (4 PIPA), and 25 heads undergoing combined (5 CPIA, 10 SCPA, 5 CTPA, 5 mini-CTPA) petrosectomies.
The results from the collected studies include that anterior petrosectomies generally afforded greater angles of attack and exposure areas (ATPA afforded a vAOA of 27.5 ± 3.9° & hAOA of 33.8 ± 2.2° compared to ETOA measurements including vAOA 8.3 ± 3.3° and hAOA of 11.8 ± 2.9° to CNVII REZ) compared to endonasal and endoscopic routes. Anterior petrosectomy offered an average volume of surgical freedom of 2649.15mm3 and the combined approach afforded volumes of surgical freedom from 1244.8 ± 253.3 mm3. Combined approaches offered wider horizontal AOAs (64.6 ± 13.6° compared to 53.0 ± 6.5° for the peritrigeminal zone) and larger exposure surfaces, with CTPA affording the greatest AOE (25.8 ± 7.9° to CN V root exit zone (REZ) and 13.2 ± 4.9° to AICA) to petroclival and brainstem regions. The mini-CTPA approach had only minor reductions in exposure to these regions (26.2 ± 12.2° to CN V root exit zone (REZ) and 12.4 ± 7.1° to AICA).
Conclusion: There is an overall need for a more generalized approach to studying and reporting measurements for skull-based cadaveric studies for petrosectomies in order to expand the comparability of reported measures. Future standardization of reporting metrics across cadaveric studies is essential to facilitate direct comparisons and meta-analytic synthesis.
