In vitro mouse model in Duchenne muscular dystrophy diagnosis using 50-MHz ultrasound waves

Velocimetric ultrasound thermometry applied to myocardium protection monitoring

Tissue temperature control during cardiac surgery is crucial for myocardial protection. To preserve the tissue, a hypothermic cardioplegia is applied in order to decrease the heart temperature down to around 10°C. The monitoring of the thermal evolution of the myocardium is then of importance to minimize deleterious effects on the heart. The present work aims at evaluating the potential of an ultrasonic velocimetric thermometry on the monitoring of in vitro tissues heating. An indentation process is first proposed to identify the experimental linear relationship linking, in myocardia, the speed of the ultrasonic longitudinal wave to the tissue temperature. An extension of this method based on the echo-tracking principle is then proposed to approach surgical conditions. Temperature changes are measured by monitoring the induced time delays of backscattered ultrasonic echoes. These results are compared to T-type thermocouple reference measurements. They are then discussed in terms of measurement precision and in situ applications.

Neuromuscular ultrasonography: quantifying muscle and nerve measurements

Neuromuscular ultrasonography can be used both descriptively and quantitatively in the evaluation of patients with neuromuscular disorders. This article reviews the quantitative use of this technology, particularly measurements of the size and echogenicity of nerve and muscle, as a tool for assessing the severity, progression, and response of these tissues to therapeutic interventions. Neuromuscular ultrasonography has several features, including portability and noninvasiveness, that make it an attractive research tool for advancing the diagnosis and treatment of neuromuscular disorders.

Identification of muscle necrosis in the mdx mouse model of Duchenne muscular dystrophy using three-dimensional optical coherence tomography

Three-dimensional optical coherence tomography (3D-OCT) was used to image the structure and pathology of skeletal muscle tissue from the treadmill-exercised mdx mouse model of human Duchenne muscular dystrophy. Optical coherence tomography (OCT) images of excised muscle samples were compared with co-registered hematoxylin and eosin-stained and Evans blue dye fluorescence histology. We show, for the first time, structural 3D-OCT images of skeletal muscle dystropathology well correlated with co-located histology. OCT could identify morphological features of interest and necrotic lesions within the muscle tissue samples based on intrinsic optical contrast. These findings demonstrate the utility of 3D-OCT for the evaluation of small-animal skeletal muscle morphology and pathology, particularly for studies of mouse models of muscular dystrophy.