Phosphorus magnetic resonance spectroscopy of the calf muscle in patients with peripheral arterial occlusive disease.

RATIONALE AND

OBJECTIVES

To investigate the potential of 31P magnetic resonance spectroscopy (MRS) in the management of severe peripheral ischemic disease, phosphocreatine:inorganic phosphate (PCr:Pi) and PCr:adenosine triphosphate (PCr:ATP) ratios were compared with a clinical ranking of arterial insufficiency.

METHODS

31P MR spectra of the muscles in the lower and upper leg were measured in a group of healthy volunteers (n = 21) and in a group of patients (n = 42) with arterial occlusive disease. The patients were graded according to the categories advised by the Ad Hoc Committee on Reporting Standards (AHCRS). Spectra were obtained 12 and 20 cm below and 15 cm above the knee joint.

RESULTS

The PCr:Pi ratio showed a significant decrease between measurements 12 and 20 cm below the knee joint for patients with severe arterial insufficiency (AHCRS 4-6), whereas this decrease was not found in patients with mild or moderate arterial insufficiency (AHCRS 1-3).

CONCLUSIONS

Although the observed spatial variation in PCr:Pi ratio measured at rest does not offer profound insight into muscle physiology, the authors' results suggest that MRS may be useful in assessing the severity of peripheral vascular disease.