Usefulness of Uptake Ratio of Three Phase Bone Scintigraphy in Complex Regional Pain Syndrome after a Stroke

Abstract

Objective: To evaluate usefulness of uptake ratio of three phase bone scintigraphy in assessing the complex regional pain syndrome (CRPS) type I in stroke patients Methods: Forty three stroke patients were diagnosed as CRPS type I based on their symptoms and confirmed by three phase bone scintigraphy. Uptake ratio was calculated by dividing the radioactivity count on the affected side by that on the unaffected side in each phase. Mean uptake ratio was compared among the groups classified by the clinical diagnosis and by the response to treatment. In addition, uptake ratio was compared before and after treatment. Results: Mean uptake ratio of the wrist in blood pool phase was significantly higher than other parts of the body (p<0.05). However, there was no significant difference among the groups classified by the clinical diagnosis nor by the response to treatment. The changes of uptake ratio were variable after treatment, but only the uptake ratio of the wrist in blood flow phase showed correlation with the degree of swelling. Conclusion: Uptake ratio of three phase bone scintigraphy was not correlated with clinical findings.