Quantitative evaluation of three-phase bone scintigraphy before and after the treatment of post-traumatic reflex sympathetic dystrophy.

Three-phase bone scans performed in 65 patients with post-traumatic reflex sympathetic dystrophy (RSD) were reviewed to evaluate which changes in uptake of the tracer appear before and after treatment, whether the form of treatment affects the intensity of uptake, and to investigate the correlation between the results of treatment and the intensity of the uptake both at initial and final scintigraphic examination. Forty-nine patients were treated using three different methods; 16 patients were observed without treatment. Bone scintigraphy was performed twice in each patient: first before treatment or observation and then at the final assessment, from 6 to 18 months after the end of treatment. Clinical results were rated as follows: good, moderate and poor. Scintigrams were evaluated quantitatively after processing the data obtained from the selected regions of interest. A significant reduction in the initially increased uptake of the tracer was noted in each phase/region of interest 6-18 months after initial imaging. At final assessment, mean uptake ratios in treated and non-treated patients were similar. This suggests that treatment does not affect the rate of reduction of uptake. In patients with good and moderate response to treatment, mean uptake ratios at initial scanning were significantly higher than in patients with poor outcome. This indicates that three-phase bone scintigraphy has prognostic value in RSD: marked hyperfixation of the tracer indicates better final outcome. At final imaging, the mean uptake ratios of patients with good, moderate and poor response to treatment did not differ significantly. This suggests that three-phase bone scintigraphy has no value in monitoring the course of treatment of RSD.