Optimizing electrical impedance myography measurements by using a multifrequency ratio: A study in Duchenne muscular dystrophy
Autor: | Aleksandar S. Mijailovic, Stefan Schwartz, Tom R. Geisbush, Seward B. Rutkove, Amy Pasternak, Basil T. Darras |
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Rok vydání: | 2015 |
Předmět: |
Male
musculoskeletal diseases Organ Culture Technique medicine.medical_specialty Adolescent Swine Duchenne muscular dystrophy Subcutaneous Fat Subcutaneous fat Article Organ Culture Techniques Physiology (medical) Electric Impedance medicine Animals Humans Child Muscle Skeletal Electrical impedance myography business.industry Myography medicine.disease Sensory Systems Rats Surgery Muscular Dystrophy Duchenne Neurology Child Preschool Phase ratio Exercise Test Neurology (clinical) business Biomedical engineering |
Zdroj: | Clinical Neurophysiology. 126:202-208 |
ISSN: | 1388-2457 |
Popis: | Electrical impedance myography (EIM) is an electrophysiological technique for neuromuscular evaluation that is impacted by subcutaneous fat (SF). Exploiting the differing frequency dependences of muscle and fat, we assessed a 2-frequency EIM phase ratio in Duchenne muscular dystrophy (DMD) boys.Twenty-eight DMD boys aged 2-13years underwent EIM and the 6-minute walk test (6MWT). For each subject, 50kHz phase data was input into the numerator while 20-500kHz phase values were input into the denominator. We then performed correlation analyses seeking to identify the denominator frequency that simultaneously optimized SF and 6MWT correlations. This optimized ratio was then tested in 24 healthy boys.50kHz phase correlated to 6MWT in DMD boys with R=0.52, p=0.0066, and to SF thickness with R=-0.67, p0.001. An optimized ratio of 50/200kHz phase reduced the correlation of SF thickness to R=-0.075, p=0.45 while improving the relationship to the 6MWT (R=0.60, p=0.001). In normal subjects, the optimization decreased SF correlation from R=0.61 from R=0.16 with 6MWT correlation remaining unchanged.The 50/200kHz EIM phase ratio removes the impact of SF while maintaining EIM's association with function.The use of a phase ratio may enhance EIM's application for evaluation of neuromuscular disease. |
Databáze: | OpenAIRE |
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