Early radiation effects on tongue function for patients with nasopharyngeal carcinoma: a preliminary study.

The purpose of this study was to investigate early radiation effects on tongue function for patients with nasopharyngeal carcinoma (NPC) and to provide a scientific database for early intervention plans. Twelve subjects with NPC and 12 age- and sex-matched normal subjects were included. Tongue maximum isometric strength and endurance at 50% of maximum strength were obtained once from normal subjects with the Iowa Oral Performance Instrument (IOPI) and twice from the NPC subjects: before and 2 months after radiation treatment. No significant differences were found in tongue function evaluation for normal or NPC groups in either pre- or post-treatments. However, this study showed that significant decreases in tongue function may not start until 2 months after treatment.