Nicht-invasive Messung der belastungsinduzierten Durchblutungsänderung cruraler Muskelgruppen - Korrelation der iso- und auxotonen Pedalergometrie mit der quantitativen computerassistierten dynamischen Kernspintomographie

This study describes the potential of dynamic contrast- enhanced magnetic resonance tomography (DCE-MRT) for the visualization and quantification of blood flow of lower leg muscles at rest and after individually adjusted muscular exercise. 41 volunteers (11 athletes, 14 individuals with a normal physical activity and 16 patients with arteriosclerosis risk without a peripheral circulatory disorder) were included in this study with a lower leg isometric stress test and a two-minute auxotonic stress test as well as a DCE-MRI beforehand and immediately following a one-minute auxotonic lower leg muscle strain on a pedal ergometer. Signal intensity curves of regions of interest (ROI) representing the peroneus, anterior tibial and gastrocnemius muscles showed a relative increase indicating blood flow reserve mobilization after exercise. Aim was to find out which parameters might allow volunteer group stratification. The lower leg two-minute stress test performance level differentiated the patient group from the other subject groups by analogy to the pre-exercise curve analysis of integral, peak enhancement, time to peak and washout of the anterior tibial and gastrocnemius muscles. Group differences were also indentified in the analysis of post exercise SI-curve parameters. Patients peak enhancement values of the gastrocnemius muscle differed significantly from those of the other two groups. Furthermore patients were distinguished from athletes by peak enhancement values of the peroneus muscles and washout values of the anterior tibial muscle. Due to direct visualization and quantitative evaluation of the peripheral microcirculation DCE-MRI linked to an adequate stress test has a diagnostic potential for monitoring therapeutic response in peripheral circulation disorders, screening and sports medicine.