Electrical Impedance Myography and Quantitative Ultrasonography: Tools to Quantify Tongue Health (P3.162)

BACKGROUND: Speech and swallowing abnormalities accompany many neuromuscular disorders for which there are limited treatment options. Reliable tools that quantify underlying motor dysfunction are needed for use in clinical therapeutic trials. Electrical impedance myography (EIM) and quantitative ultrasonography (QUS) are well-suited to provide biomarker information because the methods are painless, non-invasive, and user-friendly. Existing work indicates that EIM and QUS measurements of craniobulbar muscles, including the tongue, could provide valuable information about disease status. OBJECTIVES: 1. To compare tongue EIM and QUS data from healthy controls and neuromuscular patients with bulbar symptoms ; 2. To determine the reliability of tongue EIM and QUS measurements in healthy participants. METHODS: EIM and QUS tongue measurements were performed in 36 healthy individuals and five patients with neuromuscular disease of both genders aged 22-71 years. EIM 50 kHz phase values and QUS grayscale level (GSL) were the primary endpoints used to compute descriptive statistics. Reliability was assessed by calculating the intraclass correlation coefficient (ICC) and percent variability. RESULTS: For EIM, the average tongue values were 11.47±1.02 ° for healthy participants and 10.78±1.97 ° for patients. The intra- and inter-rater reliability ICC values obtained in the healthy subjects were 0.75 and 0.68 with 4.47[percnt] and 6.36[percnt] variability, respectively. For QUS, the average tongue values were 25.67±6.04 for healthy participants and 45.92 ±10.88 for patients. Intra- and inter-rater reliability ICC values obtained in the healthy subjects were 0.75 and 0.78 with 18.3[percnt] and 17.7[percnt] variability, respectively. CONCLUSIONS: EIM and QUS are two techniques that provide reliable tongue measurements in a group of healthy subjects, and may be helpful in distinguishing diseased from healthy tongue muscle. Further study of both techniques is warranted to determine their role as biomarkers. Disclosure: Dr. McIlduff has nothing to disclose. Dr. Yim has nothing to disclose. Dr. Geisbush has nothing to disclose. Dr. Mijailovic has nothing to disclose. Dr. Pacheck has nothing to disclose. Dr. Rutkove has received personal compensation for activities with Convergence Medical Devices as a consultant. Dr. Rutkove has received royalty payments from UpToDate and Springer.