Characteristic MR Signal of Velopharyngeal-Related Muscles on Cine-MRI in Patients with Oral Cancers and Preserved Swallowing Function: An Exploratory Feasibility Study
Shun Nishimura, Masafumi Oda, Mana Hayakawa, Shirou Tabe, Hiroki Tsurushima, Susumu Nishina, Kozue Iwawaki-Otsuka, Nao Wakasugi-Sato, Shinobu Matsumoto-Takeda, Osamu Takahashi, Kazuya Haraguchi, Shinji Yoshii, Manabu Habu, Izumi Yoshioka, Toyohiro Kagawa, Yasuhiro MorimotoBackground/Objectives: Surgically treated oral cancer patients often face velopharyngeal insufficiency, which adversely impacts their quality of life (QOL). Our past investigations revealed noticeable MR signal shifts in velopharyngeal-related muscles during water deglutition on CMR among healthy individuals. We hypothesized that analyzing these distinct signal fluctuations could offer a novel visual perspective for detecting deglutition anomalies in surgical oral cancer cases. This feasibility study aimed to assess velopharyngeal-related muscular performance via CMR in post-operative oral cancer patients. Methods: Nineteen patients with oral malignancies were prospectively evaluated pre- and post-operatively. Twelve quantitative CMR metrics alongside subjective dysphagia scores were investigated. We analyzed whether signal intensity (SI) ratio alterations in these muscles correlated with dysphagia severity and clinical parameters. Results: Although three specific CMR parameters significantly worsened post-operatively, muscle MR signal values increased during deglutition without significant variation between pre- and post-surgical states. Subjective swallowing assessments remained entirely normal across all subjects. Conclusions: This preliminary investigation indicates that CMR can visualize stable velopharyngeal-related muscle activity after surgery in oral cancer patients maintaining adequate swallowing status. Nevertheless, confirmation via larger, symptomatic patient cohorts alongside gold-standard techniques remains mandatory.