Luciano C. Leonel PhD; Maria Peris-Celda MD PhD; John I. Lane MD; Jamie J. Van Gompel MD; Matthew L. Carlson MD
Educational Objective: At the conclusion of this presentation, the participants should be able to better understand the surgical exposure advantages and limitations of the variation of infratemporal fossa type A approaches, which would be helpful in tailoring approaches to optimize exposure for each unique jugular foramen tumor.
Objectives: To compare variable surgical exposure of critical structures obtained in classic and modified infratemporal fossa type A approaches (ITFA) to the jugular foramen.
Study Design: Cadaveric dissection.
Methods: Three cadaveric specimens were dissected and each critical approach step was documented with 3D and 2D photographic images. Computed tomography (CT) imaging at pre-, mid-, and post-dissection timepoints demonstrate the progression of exposure. Photogrammetry of 3D printed models of final dissections highlight final exposure of critical structures. Surgical exposure of the carotid artery, jugular foramen, intralabyrinthine corridor, and petrous apex were compared across approach variations.
Results: Dissections progressing from maximal structural preservation to maximal exposure were performed: 1) modified ITFA with preservation of the external auditory canal (EAC) and fallopian bridge; 2) modified ITFA with subtotal petrosectomy and fallopian bridge; and 3) classic ITFA with subtotal petrosectomy and anterior facial nerve transposition. Stepwise progression of bony removal allowed for intra-specimen control for anatomic variability. CT, 3D printed models and photogrammetry analysis of the approaches demonstrated excellent access to the petrous carotid artery, jugular foramen, intralabyrinthine corridor, and petrous apex. Presentation will provide practical guidelines and anatomical image and model resources.
Conclusions: While the classic ITFA offered the greatest surgical exposure of the jugular foramen, petrous carotid artery, and petrous apex, more limited dissections with preservation of the external auditory canal and fallopian bridge offered excellent access to critical structures. Understanding the limitations of each approach allows the surgeon to optimally balance sufficient exposure for tumor resection and maximal function preservation.