Magnetic resonance imaging of the levator veli palatini muscle during speech.
OBJECTIVE
To obtain detailed anatomic information on the levator veli palatini (LVP) muscle from magnetic resonance imaging (MRI). Quantitative measures of the configuration of the LVP muscle at rest and during speech activities were obtained.


METHODS
Prospective study using MRI of adult subjects with normal velopharyngeal mechanisms to determine anatomic and physiologic parameters of the levator muscle. The levator veli palatini muscle was imaged at rest and during speech activities consisting of nasal and non-nasal sounds mixed with vowels, consonants, or both (e.g., /ansa, asna, amfa, afma/).


METHODS
Ten normal healthy adults (five men, five women) between 21 and 53 years of age and free of oropharyngeal abnormalities.


METHODS
Two-dimensional spin echo static images and dynamic fast gradient echo images of the levator muscle in both the sagittal and oblique/coronal planes.


RESULTS
On average across female (F) and male (M) subjects: distance between LVP muscle origin points, 52.6 mm (F), 54.6 mm (M); angle of levator muscle origin at rest, 64.5 degrees (F), 60.4 degrees (M); length of the levator muscle at rest, 44.1 mm (F), 46.4 mm (M); width of levator muscle at lateral margin of velum, 5.5 mm (F), 6.6 mm (M). Both the levator muscle angle of origin and length became progressively smaller from rest, nasal consonants, low vowels, high vowels, and fricatives for both female and male subjects. Across all subjects, there was a 19% reduction in length of the LVP muscle from rest position to fricative production.


CONCLUSIONS
MRI is an effective method of imaging and measuring the LVP muscle and related structures in living subjects. Understanding the normal tissue distribution and quantification of the LVP muscle provides important information for development of a functional biomechanical model of the velopharynx and for improved surgical treatment.
Ettema
Sandra L
SL
Medical Scholars Program, University of Illinois at Urbana-Champaign, 61820, USA. ettema@uiuc.edu.
Kuehn
David P
DP
Perlman
Adrienne L
AL
Alperin
Noam
N
D000328:Adult; D002508:Cephalometry; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016014:Linear Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009305:Nasopharynx / Q000033:anatomy & histology / Q000502:physiology; D015588:Observer Variation; D009960:Oropharynx / Q000033:anatomy & histology / Q000502:physiology; D010156:Palatal Muscles / Q000033:anatomy & histology* / Q000502:physiology; D010160:Palate, Soft / Q000033:anatomy & histology / Q000502:physiology; D010614:Pharynx / Q000033:anatomy & histology / Q000502:physiology; D010700:Phonetics; D011446:Prospective Studies; D012044:Regression Analysis; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013060:Speech / Q000502:physiology*; D013223:Statistics as Topic