T.P.48: Acoustic radiation force impulse imaging for the longitudinal assessment of muscle tissue stiffness in collagen 6 myopathy and LAMA2 related muscular dystrophy

Acoustic Radiation Force Impulse (ARFI)-Imaging is a non-invasive ultrasound-based operator independent elastography method that assesses tissue stiffness. ARFI mechanically excites tissues with localized impulsive radiation resulting in shear wave propagation (m/s) away from the region of excitation. Shear wave velocity (SWV) increases when tissue is stiffer, and in muscle disorders, this may be related to either fibrosis or edema. Here we address the sensitivity and specificity of ARFI-imaging to changes in the individual muscles of patients with collagen 6 myopathy (COL6) and LAMA2 related muscular dystrophy (LAMA2), as a reflection of disease progression over 1year. The goal of this study is to identify whether or not ARFI imaging could be used as a biomarker for disease progression and/or response to therapeutic intervention in a clinical trial. SWV values were obtained from children ages 5–18 by a single examiner. Values from 11 male and 9 female COL6 and 7 male and 8 female LAMA2 patients were compared to 12 male and 12 female age and sex matched healthy volunteers using an ACUSONS2000 Siemens Medical Solutions Ultrasound machine and 9L4 MHz linear array transducer. All studies were performed with the patient in the supine position with arms supinated. All measurements were obtained at fixed proportional distances over the muscles of interest. Data acquired as a cross sectional measurement of shear wave velocity in these patient populations revealed that out of an in...
Source: Neuromuscular Disorders - Category: Neurology Authors: Source Type: research