[Scintigraphic study of reflex algodystrophy].

Isotope investigation of reflex sympathetic dystrophy is not limited to an evaluation of bony up-take, it also includes examination of the early dynamic scintigraphy of the vessels. The late views of bone scans reflect, above all, the bone's affinity for phosphate complexes i.e. the degree of osteoblast activity. Generally, dystrophies, independent of their site, show increased locoregional uptake, often quite intense, which appears early in the course of the disease. This supports histopathological findings. There are several advantages in using the bone scan in the investigation of reflex dystrophy: early diagnosis before the development of radiological signs, precise evaluation of the local extension of the dystrophic process and detection of the incidence of multifocal forms, follow-up of the course of the disease, definition of new clinical forms: patchy algodystrophy partial, decalcifying dystrophy, sub-radiological dystrophy, the aetiology in certain sites (especially the hip). Early dynamic scans that dystrophy is accompanied by an increase in the vascular compartment and decreased circulatory flow, a sign of the local stage of the disease. There is also an increase of the interstitial compartment, greater than that of the vascular compartment, explaining the presence of edema. The pathophysiological information gained from dynamic studies is matched by the therapeutic information: evaluation, or even prediction, of the effect of a given drug (cortisone, calcitonin).