RESUMO
INTRODUCTION: Electrical impedance myography (EIM) has been proposed as a noninvasive biomarker of muscle composition in facioscapulohumeral muscular dystrophy (FSHD). Here we determine the associations of EIM variables with muscle structure measured by MRI. METHODS: We evaluated 20 patients with FSHD at two centers, comparing EIM measurements (resistance, reactance, and phase at 50, 100, and 211 kHZ) recorded from bilateral vastus lateralis, tibialis anterior, and medial gastrocnemius muscles to MRI skin and subcutaneous fat thickness, MRI T1-based muscle severity score (T1 muscle score), and MRI quantitative intramuscular Dixon fat fraction (FF). RESULTS: While reactance and phase both correlated with FF and T1 muscle score, 50 kHz reactance was most sensitive to muscle structure alterations measured by both T1 score (ρ = -0.71, P < .001) and FF (ρ = -0.74, P < .001). DISCUSSION: This study establishes the correlation of EIM with structural MRI features in FSHD and supports further evaluation of EIM as a potential biomarker in FSHD clinical trials.
Assuntos
Impedância Elétrica , Músculo Esquelético/fisiopatologia , Distrofia Muscular Facioescapuloumeral/fisiopatologia , Miografia/métodos , Músculo Quadríceps/fisiopatologia , Tecido Adiposo/diagnóstico por imagem , Adulto , Idoso , Eletrodiagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Distrofia Muscular Facioescapuloumeral/diagnóstico por imagem , Tamanho do Órgão , Músculo Quadríceps/diagnóstico por imagem , Gordura Subcutânea/diagnóstico por imagemRESUMO
Diabetic lumbosacral radiculoplexus neuropathy, also known as diabetic amyotrophy, has a characteristic course of sudden onset of unilateral pain in the thigh and hip, which may spread to the other side in weeks to months and proceeds with progressive lower extremity weakness, often resulting in the inability to walk unassisted. The syndrome is typically monophasic, and most patients will recover at least to some degree. Less typical features include lack of pain, distal predominant weakness, absence of diabetes, and upper extremity involvement. This article provides a series of interesting cases to highlight the diagnostic challenges and discusses management decision making.