Alberto Di Somma1, Norberto Andaluz2, Steven L Gogela2, Luigi Maria Cavallo3, Jeffrey T Keller2, Alberto Prats-Galino4, Paolo Cappabianca3. 1. Division of Neurosurgery, School of Medicine and Surgery, Universita degli Studi di Napoli Federico II, Naples, Italy. Electronic address: albertodisomma87@gmail.com. 2. Department of Neurosurgery, University of Cincinnati College of Medicine, Comprehensive Stroke Center at UC Neuroscience Institute, Mayfield Clinic, Cincinnati, Ohio, USA. 3. Division of Neurosurgery, School of Medicine and Surgery, Universita degli Studi di Napoli Federico II, Naples, Italy. 4. Laboratory of Surgical Neuroanatomy, Faculty of Medicine, Universitat de Barcelona, Barcelona, Spain.
Abstract
BACKGROUND AND OBJECTIVE: Various surgical routes have been used to decompress the intracanalicular optic nerve. Historically, a transcranial corridor was used, but more recently, ventral approaches (endonasal and/or transorbital) have been proposed, individually or in combination. The present study aims to detail and quantify the amount of bony optic canal removal that may be achieved via transcranial, transorbital, and endonasal pathways. In addition, the surgical freedom of each approach was analyzed. METHODS: In 10 cadaveric specimens (20 canals), optic canals were decompressed via pterional, endoscopic endonasal, and endoscopic superior eyelid transorbital corridors. The surgical freedom and circumferential optic canal decompression afforded by each approach was quantitatively analyzed. Statistical comparison was carried using a nonpaired Student t test. RESULTS: An open pterional transcranial approach allowed the greatest area of surgical freedom (transcranial, 109.4 ± 33.6 cm2; transorbital, 37.2 ± 4.9 cm2; endonasal homolateral, 10.9 ± 5.2 cm2; and endonasal contralateral, 11.1 ± 5.6 cm2) with widest optic canal decompression compared with the other 2 ventral routes (transcranial, 245.2; transorbital, 177.9; endonasal, 144.6). These differences reached, in many cases, statistical significance for the transcranial approach. CONCLUSIONS: This anatomic contribution provides a comprehensive evaluation of surgical access to the optic canal via 3 distinct, but complementary, approaches: transcranial, transorbital, and endonasal. Our results show that, as expected, a transcranial approach achieved the widest degree of circumferential optic canal decompression and the greatest surgical freedom for manipulation of surgical instruments. Further surgical experience is necessary to determine the proper surgical indication for the transorbital approach to this disease.
BACKGROUND AND OBJECTIVE: Various surgical routes have been used to decompress the intracanalicular optic nerve. Historically, a transcranial corridor was used, but more recently, ventral approaches (endonasal and/or transorbital) have been proposed, individually or in combination. The present study aims to detail and quantify the amount of bony optic canal removal that may be achieved via transcranial, transorbital, and endonasal pathways. In addition, the surgical freedom of each approach was analyzed. METHODS: In 10 cadaveric specimens (20 canals), optic canals were decompressed via pterional, endoscopic endonasal, and endoscopic superior eyelid transorbital corridors. The surgical freedom and circumferential optic canal decompression afforded by each approach was quantitatively analyzed. Statistical comparison was carried using a nonpaired Student t test. RESULTS: An open pterional transcranial approach allowed the greatest area of surgical freedom (transcranial, 109.4 ± 33.6 cm2; transorbital, 37.2 ± 4.9 cm2; endonasal homolateral, 10.9 ± 5.2 cm2; and endonasal contralateral, 11.1 ± 5.6 cm2) with widest optic canal decompression compared with the other 2 ventral routes (transcranial, 245.2; transorbital, 177.9; endonasal, 144.6). These differences reached, in many cases, statistical significance for the transcranial approach. CONCLUSIONS: This anatomic contribution provides a comprehensive evaluation of surgical access to the optic canal via 3 distinct, but complementary, approaches: transcranial, transorbital, and endonasal. Our results show that, as expected, a transcranial approach achieved the widest degree of circumferential optic canal decompression and the greatest surgical freedom for manipulation of surgical instruments. Further surgical experience is necessary to determine the proper surgical indication for the transorbital approach to this disease.
Authors: Jun Kim; Aaron R Plitt; Awais Vance; Scott Connors; James Caruso; Babu Welch; Tomas Garzon-Muvdi Journal: J Neurol Surg B Skull Base Date: 2021-05-29
Authors: Davide Locatelli; Francesco Restelli; Tommaso Alfiero; Alberto Campione; Fabio Pozzi; Sergio Balbi; Alberto Arosio; Paolo Castelnuovo Journal: J Neurol Surg B Skull Base Date: 2020-12-22