Stroke(CVA), the most common disorder of the central nervous system(CNS), exhibits various clinical symptoms according to the location and the size of the lesion. The major manifestations include muscle weakness of the affected side(hemiparesis), sensory dysfunction, and speech impairment. Among them, hemiparesis is the most debilitating component of stroke for many patients, which results in serious limitations to successful carrying on independent activities of daily living(ADL) and social living. One potentially critical area of stroke research, the abnormality of the energy metabolism in the hemiparetic muscle secondary to stroke, has been largely neglected.

Thus, the object of this investigation was to measure and observe the metabolic changes of the hemiparetic limb muscle in stroke patients using 31P magnetic resonance spectroscopy. Spectrum data were obtained from the flexor digitorum superficialis muscles of both, affected and unaffected, sides and analyzed statistically. For this study, 16 male stroke patients were selected as test subjects.

The results showed that the intracellar Pi/PCr ratio was 0.18±0.01 on the affected side compared to 0.14±0.01 on the unaffected side, resulting in a statistically significant increase(p<0.05). Intracellular pH level(7.00±01) was found to be significantly higher(p<0.05) on the affected side compared to the unaffected side(6.98±0.01). Although the hemiparetic conditions of the affected muscles, such as muscle atrophy and motor recovery were not reflected by the intracell-ular Pi/PCr ratio or the pH level, it was evident that the longer duration of the stroke in patients corresponded to a significant increase(p<0.05) of the Pi/PCr ratio. Also, signal density of phosphodiester was detected in the affected side in 8 out of the 16 tested patients.

From these results, the author was able to confirm the decreases in energy storage capacity(due to reduced mitochondria activity) of the cell and the possibility of an injured cell membrane in a hemiparetic muscle cell found in stroke patients.