436 Gac Med Mex. 2023;159:436-438 Contents available at PubMed www.gacetamedicademexico.com Date of reception: 26-06-2023 Date of acceptance: 02-10-2023 DOI: 10.24875/GMM.M23000825 Background Trigeminal neuralgia continues to be one of current neurosurgical challenges for achieving neuropathic pain long-term control. In refractory cases, surgical management may be required. 1,2 Microvascular decompression is a non-lesional ap- proach that preserves trigeminal nerve function and allows good long-term resolution, in addition to being potentially curative. Microsurgical dissection is used in the emergency zone of the nerve at its origin in the brain stem (transition zone) and a support or prosthe- sis is used to maintain separation of the vessel and avoid direct contact with the nerve. For this, different materials have been used, such as Teflon, to avoid the pulsatile or kinking phenomenon on the nerve. 3-6 The effect of the material is not innocuous, since com- plications deriving from prosthetic materials have been described. 7 Translational innovation provides biomaterials and scaffolds that offer the advantage of being biocom- patible, biodegradable, non-toxic and able to provide regenerative action. In the scientific literature there are no reports on the use of chitosan sponge with the purpose to provide a dual prosthetic and regenerative effect. This report proposes this pilot phase of eval- uation of tolerance to the biomaterial in the brain stem of humans in two representative cases. 8-10 Stage I: 3D scaffold design Study stage preceded by a line of translational re- search in which design evaluations, tissue engineering, and analysis of biomaterials, biocompatibility, toxicity and biodegradability were carried out. Medium molec- ular weight biomedical-grade chitosan, with 75-85% deacetylation, was used in a powder form from Sigma Aldrich ® , USA. For the synthesis of the 3D porous sponge, a 4% chitosan solution was initially used and, for proper solubilization, it was mixed with 2% acetic acid. Subsequently, it was placed on a Petri dish, where the process of precipitation, washing, pH verification, freeze-drying and design of layers and porosity was completed, to be complemented with double steriliza- tion in autoclave and gas (ethylene oxide). Stage II: application to clinical cases Case 1 After notification and review of the informed consent process for the pilot cases and review of ethical impli- cations, microsurgical application was carried out through selective right sub-occipital craniectomy. Sev- enty-two-year-old female patient with a history of 6 years of pain due to trigeminal neuralgia that worsened within the last 6 months, refractory to pharmacological treatment, multiple side effects, liver toxicity and malnutrition. Chitosan implant in microvascular decompression of trigeminal neuralgia: a translational perspective Implante de quitosana en la neuralgia del trigémino en humanos: una perspectiva traslacional Rodrigo Ramos-Zúñiga,* Martín Rodríguez-Vázquez, Sandra Trejo-Gallegos and Laura Lara-Reynoso Department of Neurosciences, Institute of Translational Neurosciences, University Center of Health Sciences, Universidad de Guadalajara, Guadalajara, Mexico 0016-3813/© 2023 Academia Nacional de Medicina de México, A.C.. Published by Permanyer. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). GACETA MÉDICA DE MÉXICO BRIEF COMMUNICATION *Correspondence: Rodrigo Ramos-Zúñiga E-mail: rodrigorz13@gmail.com