Modern approach in microsurgical elimination of tongue defects using computerized digital planning

Introduction. The treatment of malignant neoplasms of the oral mucosa implies a combined treatment, whose first stage generally involves surgery. However, the most common non-personalized surgical methods are based on resection of the tongue, often affecting more than half of the organ, which can lead to significant functional deficiency and disability of patients. Objective. To demonstrate the possibility of tongue defect reconstruction using preoperative computer 3D planning through clinical cases. Ма terials and methods. From 2021 to 2024, four patients with primary cancer of the lateral surface of the tongue were operated on using this methodology at the Maxillofacial Surgery Department of the NMICO FMBA of Russia. All patients underwent hemiglossectomy and preventive cervical lymphadenectomy on the affected side, with simultaneous reconstruction of the tongue using a radial forearm flap. The average age of the patients was 53 years; males outnumbered females by a ratio of 3:1. Patients presented with stages rT1-rT4; histological examination revealed no regional lymph node involvement (N0) in any patient. Preoperative instrumental examinations included: magnetic resonance imaging (MRI) of the soft tissues of the maxillofacial area with contrast enhancement; multislice computed tomography (MSCT) of the maxillofacial area with contrast enhancement; MSCT of the donor area (forearm) with contrast enhancement; Doppler ultrasound of the brachiocephalic trunk vessels and donor area vessels; transnasal endoscopic laryngoscopy with swallowing tests (three-swallow test) with video recording. All patients were surveyed preoperatively and postoperatively using EORT QLQ — H&N35, EORT QLQ — C30, FACT– H&N, MD Anderson, and VHI-10 questionnaires. Patients with abundant hair in the donor area underwent laser hair removal prior to hospitalization. After performing computer simulation of the surgical intervention using Slicer and Blender software, templates were printed on a Elegoo Saturn 2 printer. Assessment of speech and swallowing functions was carried out by a speech therapist specializing in these areas using the Pokrovsky protocol and Vospector-DSI software at both preoperative and postoperative stages. The attending physician performed anthropophotometry and video recording of patient complaints and speech at all stages of care. The postoperative period was without complications; nasogastric tubes were removed on the 12th day; the average hospital stay was 14 days. Results. The flap survival rate was 100% across the entire series of observations. Oncological radicality was achieved at R0 for all patients. The average duration of the surgical intervention was 288 minutes. In three patients, the acoustic parameters of speech were within normal limits (in one patient, this parameter could not be assessed due to systemic speech underdevelopment caused by hearing impairment). The average syllable intelligibility coefficient according to Pokrovsky was 88%. All patients adapted to their usual diet and continued their professional activities. According to the results of the EORT QLQ — H&N35, EORT QLQ — C30, and FACT — H&N questionnaires, patients rated their quality of life as good in one case and excellent in three cases. Conclusions. The developed algorithm for preoperative computer planning is promising. The use of surgical templates allowed for adequate oncological radicality, synchronized the simultaneous work of two surgical teams, reduced the duration of anesthetic assistance (with an average surgical intervention time of 288 minutes), and achieved good functional and aesthetic results. However, this methodology requires further refinement in a larger group of patients.