Assessment Of Myopathies Research Articles

An image processing strategy for the quantification and visualization of exercise-induced muscle MRI signal enhancement.

Exercise increases the skeletal muscle water signal in T2-weighted images. Potential medical applications of MR studies of exercise-induced muscle signal intensity changes are the assessment of myopathies, sport training regimens, and physical therapy approaches following surgeries. We developed an automated image processing technique that provides volumetric analysis and visualization of exercise-related T2-weighted image intensity changes. The image processing was applied to the segmentation and quantification of activated muscle volumes. Qualitative assessment of muscle activation is demonstrated with three-dimensional surface rendering. Quantitative determination of active muscle volume, signal intensity, and change over time is demonstrated. Visualization of the activated muscles allows functional anatomical assessment of exercise, which in turn allows detection of muscle utilization.

Turns-amplitude analysis assessment of myopathies in HIV-infected patients

Electromyographic interference patterns during a gradual increase in force were studied by means of the turns-amplitude analysis in a series of HIV-infected patients with and without clinical, biological and histological signs of myopathy. Different parameters were evaluated to determine their sensitivity for the diagnosis of the myopathies that occur in this context. The studied parameters were the number of turns (NT), the mean amplitude of the turns (MA) and the ratio NT MA (RTA). For each parameter, we compared the interest of mean values, calculated at moderate contraction, to that of peak values. In addition, the shape of the cloud of MA plotted versus NT data points was analyzed. The sensitivity of the turns-amplitude analysis was 95% for the diagnosis of myopathy when NT, MA and RTA were taken together into account, versus 80% in the cloud studies. Peak values were the most sensitive criteria, but mean values abnormalities were observed in some cases of zidovudine myopathy, indicating a potential usefulness of this quantitative EMG method in the differential diagnosis among myopathies in HIV-infected patients.