Internal three dimensional tongue motion during /s/ and /S/ from tagged magnetic resonance imaging; control and glossectomy motion

This study aims to ascertain the effects of differences in closure procedure afer tongue cancer surgery (glossectomy) on tongue motion during the speech sounds /s/ and RI. Subjects were one control and two post-glossectomy patients. The patients had similar resections, but different closure procedure. Cine and tagged-M data were recorded of tongue motion during speech in axial, coronal and sagittal orientations at 26 fps. 3D tissue point motion was tracked at every time-frame in the word. 3D displacement fields were calculated at each time-frame to show tissue motion during speech. A previous pilot study showed difference among these subjects in /s/ production [Pedersen, et al, JASA, 2013A]. Specifically, they differed in internal tongue motion patten, and the flap patient had unusual Genioglossus lengthening patterns. The /s/ require a midline tongue groove, which is challenging for the patients. The present study continue that effort by adding the motion of /S/ because /S/ doe not require a midline groove and may be easier for the patients to pronounce Two additional muscle are studied, to determine how they interact to produce successful motion.