title: Quantitative analysis of surgical exposure and surgical freedom to the anterosuperior pons: comparison of pterional transtentorial, orbitozygomatic, and anterior petrosal approaches.
abstract: Surgical approaches to the pons lump together different areas of the pons, such as the anterosuperior and the anteroinferior pons. These areas are topographically different, and different approaches may be best suited for one or the other area. We evaluated the exposure of the anterosuperior pons using different surgical approaches. We quantify the surgical exposure and surgical freedom to the anterosuperior pons afforded by the pterional transtentorial (PT), the orbitozygomatic with anterior clinoidectomy (OZ), and the anterior petrosal (AP) approaches. Five embalmed cadaver heads were used. The three approaches were executed on each side, for a total of 30 approaches. The area of maximal exposure of the anterosuperior pons was measured with the aid of neuronavigation. We also evaluated the feasible angles of approach in the vertical and horizontal planes. We were able to successfully expose the anterosuperior pons using all the selected approaches. In the PT and OZ approaches, mobilization of the sphenoparietal sinus can prevent over-retraction of the temporal bridging veins, while use of the endoscope can help in preserving the integrity of the fourth nerve while cutting the tentorium. The mean exposure area was largest for the AP and smallest for the PT; the surgical freedom was similar among all the approaches. However, there was no statistically significant difference among all the approaches in the exposure area or in the surgical freedom. There is no significant difference among the three evaluated approaches in exposure of the anterosuperior pons.
authors.affiliation: Section of Neurosurgery, Department of Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.|Dardinger Microneurosurgical Skull Base Laboratory, Department of Neurological Surgery, Wexner Medical Center, The Ohio State University, Columbus, OH, USA.
authors.forename: Jung-Shun
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Institute of Neurosurgery, Catholic University of Rome, Rome, Italy.|Dardinger Microneurosurgical Skull Base Laboratory, Department of Neurological Surgery, Wexner Medical Center, The Ohio State University, Columbus, OH, USA.
authors.forename: Alba
authors.initials: A
authors.lastname: Scerrati
authors.affiliation: Department of Radiology and Wright Center of Innovation in Biomedical Imaging, Wexner Medical Center, The Ohio State University, N1025 Doan Hall, 410 West 10th Avenue, Columbus, OH, 43210, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Dardinger Microneurosurgical Skull Base Laboratory, Department of Neurological Surgery, Wexner Medical Center, The Ohio State University, Columbus, OH, USA. mario.ammirati@osumc.edu.
authors.forename: Mario
authors.initials: M
authors.lastname: Ammirati
mesh_terms: D002102:Cadaver; D002426:Cavernous Sinus / Q000601:surgery*; D003399:Craniotomy / Q000379:methods; D004388:Dura Mater / Q000601:surgery; D006801:Humans; D038361:Neuronavigation / Q000379:methods; D019635:Neurosurgical Procedures; D011149:Pons / Q000601:surgery*
keywords: Anterior petrosal approach; Anterosuperior pons; Orbitozygomatic with anterior clinoidectomy; Pterional transtentorial approach