Regional cerebral perfusion before and after parathyroidectomy

Single photon emission computerised tomography (SPECT) is used to study cerebral blood-flow and cerebral metabolism in various neuropsychiatric disorders. Reduced regional cerebral blood flow has been demonstrated in patients with depression and chronic fatigue, symptoms that are common in primary hyperparathyroidism. The aim of this study was to reveal possible changes in regional cerebral blood flow in patients with primary hyperparathyroidism before and after operative treatment. Prospective study of regional cerebral blood flow in 16 consecutive women of median age 72 (range 50-82 years) using SPECT with 99m Tc-labelled hexamethylpropylenamine oxime. The measurements were performed before and two, four and twelve months after parathyroidectomy. The Montgomery and Asberg depression rating scale (MADRS) was used as a parallel clinical test. Reduced (pathological) regional cerebral blood flow was seen before operation in 14 patients, 13 with solitary adenoma and one with double adenoma. After surgery, this improved to normal values in 13, but was further reduced in one. In two patients with preoperative normal regional cerebral blood flow, both of them asymptomatic and with diffuse hyperplasia, a slight reduction was demonstrated. Eight patients had a pathological preoperative MADRS score, which normalised in seven after surgical treatment. The finding of reduced regional cerebral blood flow in patients with primary hyperparathyroidism followed by significant improvement after operation might have bearing upon the case for surgical treatment.