Analysis of speech and tongue motion in normal and post-glossectomy speaker using cine MRI.
OBJECTIVE
Since the tongue is the oral structure responsible for mastication, pronunciation, and swallowing functions, patients who undergo glossectomy can be affected in various aspects of these functions. The vowel /i/ uses the tongue shape, whereas /u/ uses tongue and lip shapes. The purpose of this study is to investigate the morphological changes of the tongue and the adaptation of pronunciation using cine MRI for speech of patients who undergo glossectomy.


METHODS
Twenty-three controls (11 males and 12 females) and 13 patients (eight males and five females) volunteered to participate in the experiment. The patients underwent glossectomy surgery for T1 or T2 lateral lingual tumors. The speech tasks "a souk" and "a geese" were spoken by all subjects providing data for the vowels /u/ and /i/. Cine MRI and speech acoustics were recorded and measured to compare the changes in the tongue with vowel acoustics after surgery. 2D measurements were made of the interlip distance, tongue-palate distance, tongue position (anterior-posterior and superior-inferior), tongue height on the left and right sides, and pharynx size. Vowel formants Fl, F2, and F3 were measured.


RESULTS
The patients had significantly lower F2/Fl ratios (F=5.911, p=0.018), and lower F3/F1 ratios that approached significance. This was seen primarily in the /u/ data. Patients had flatter tongue shapes than controls with a greater effect seen in /u/ than /i/.


CONCLUSIONS
The patients showed complex adaptation motion in order to preserve the acoustic integrity of the vowels, and the tongue modified cavity size relationships to maintain the value of the formant frequencies.
University of Ulsan, Ulsan University Hospital, College of Medicine, Department of Dentistry, Ulsan, South Korea.
Jinhee
J
Ha
University of Ulsan, Ulsan University Hospital, College of Medicine, Department of Oral and Maxillofacial Surgery, Ulsan, South Korea.
Iel-Yong
IY
Sung
University of Ulsan, Ulsan University Hospital, College of Medicine, Department of Oral and Maxillofacial Surgery, Ulsan, South Korea.
Jang-Ho
JH
Son
University of Maryland, Department of Oral and Craniofacial Biological Science, Baltimore, United States of America.
Maureen
M
Stone
University of Maryland, Department of Oral and Maxillofacial Surgery, Baltimore, United States of America.
Robert
R
Ord
University of Ulsan, Ulsan University Hospital, College of Medicine, Department of Oral and Maxillofacial Surgery, Ulsan, South Korea.
Yeong-Cheol
YC
Cho
D000328:Adult; D000704:Analysis of Variance; D059925:Anatomic Landmarks; D016022:Case-Control Studies; D005260:Female; D005927:Glossectomy / Q000534:rehabilitation*; D006801:Humans; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D010614:Pharynx / Q000473:pathology / Q000503:physiopathology; D011184:Postoperative Period; D012016:Reference Values; D012189:Retrospective Studies; D013060:Speech / Q000502:physiology*; D013061:Speech Acoustics; D014059:Tongue / Q000473:pathology* / Q000503:physiopathology*; D014062:Tongue Neoplasms / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D016896:Treatment Outcome