INCREASED CEREBRAL BLOOD-FLOW IN DEPRESSED-PATIENTS RESPONDING TO ELECTROCONVULSIVE-THERAPY

Considerable data support the existence of impaired regional cerebral blood flow (rCBF) in major depression. We compared rCBF in depressed p atients before and after electroconvulsive therapy (ECT) to define whe ther the impairment is a ''state''-related property or a trait phenome non. Methods: Twenty patients with a major depressive disorder were st udied by Tc-99m-HMPAO brain SPECT, 2-4 days before and 5-8 days after a course of ECT. Three transaxial brain slices delineating anatomicall y defined regions of interest at approximately 4, 6 and 7 cm above the orbitomeatal line were used, with the average number of counts for ea ch region of interest normalized to the area of maximal cerebellar upt ake. Results: Technetium-99m-HMPAO uptake significantly increased in p atients who responded to ECT but remained unchanged in patients who di d not respond to the treatment (response defined as a reduction of at least 60% on the Hamilton Depression Rating Scale). An inverse correla tion was observed between severity of depression and HMPAO uptake, and clinical improvement was positively correlated with the increase in t racer uptake. Conclusions: These findings imply that reduced rCBF in d epression, as reflected in brain Tc-99m-HMPAO uptake, is a ''state''-r elated property and is reversible by successful treatment. Technetium- 99m-HMPAO uptake may serve as an objective state marker for depression , as an indicator of the severity of depression and as an objective me ans of evaluating response to treatment.