DYNAMIC (31)PHOSPHORUS MAGNETIC-RESONANCE SPECTROSCOPY OF THE QUADRICEPS MUSCLE - THERAPY-INDUCED CHANGES IN ARTERIAL OCCLUSIVE DISEASE

Purpose: The present investigation aimed at examining changes in muscl e metabolism caused by treatment of arterial occlusive disease, using dynamic (31)phosphorus methods. Method: 32 patients with arterial occl usive disease were examined in a 1.5 T apparatus with a 6 cm surface c oil before and after treatment. The metabolic changes in the quadricep s muscles were visualised during a 36 s phosphorus spectrum during res t, exercise (isometric and isotonic) and during a period of recovery. Results: Vascular therapy resulted in a significant increase in the du ration of both types of exercise during dynamic phosphorus spectroscop y (isometric exercise: 282 s against 199 s; p = 0.002, isotonic exerci se: 575 s against 222 s; p = 5 x 10(-6)). After treatment, exercise-in duced changes in pH (7.00 against 6.94; p = 0.004 and 7.00 against 6.9 3; p = 0.02) and the ratio P-i/PCr (0.34 against 0.44; p = 0.002 and 0 .36 against 0.50; p = 0.009) were significantly smaller than before th erapy, using a similar amount of exercise. Recovery time of P-i/PCr (4 5 s against 82 s; p = 10(-5) and 42 s against 57 s; p = 0.01) and pH v alue (154s against 181s; p = 0.14 and 173s against 214s; p=0.22) showe d significant reduction after treatment. Conclusions: Dynamic (31)phos phorus magnetic resonance spectroscopy indicates increased mitochondri al oxydative capacity in the quadriceps muscles as evidence for increa sed oxygen supply to muscle tissue following vascular therapy.