Central pain after pontine infarction is associated with changes in opioid receptor binding: A PET study with ¹¹C-diprenorphine

Using ¹⁸F-fluorodeoxyglucose and ¹¹C-diprenorphine positron emission tomography (PET), we investigated alterations in glucose metabolism and opioid receptor binding in a patient with central poststroke pain, which developed after a small pontine hemorrhagic infarction. In comparison with normal databases, reduced ¹¹C-diprenorphine binding was more accentuated than the hypometabolism on the lateral cortical surface contralateral to the symptoms, and a differential abnormal distribution between the tracers was seen in pain-related central structures. These results show that ¹¹C- diprenorphine PET provides unique information for the understanding of central poststroke pain.