Study: Cerebral blood flow impaired in depression
According to a study published in this month’s Journal of Nuclear Medicine, individuals in a depressed emotional state have impaired cerebral blood flow. The findings suggest that objective imaging-based evaluations could be used to support subjective observer-based judgment in clinical decisions for treating depression.

The study, conducted by the department of psychiatry at Hadassah-Hebrew University Medical Center in Jerusalem, used SPECT imaging to confirm that cerebral blood flow in depressed patients is lower than in healthy control subjects, especially in frontal, limbic and subcortical brain regions.

Israeli researchers studied 33 depressed patients and 25 healthy control subjects with SPECT and the radiotracer 99mTc-HMPAO.

The researchers then utilized the modality to examine cerebral blood flow after the patients were treated for clinical depression. They found that clinical improvement in depression is accompanied by diverse changes in cerebral blood flow, according to whether patients are treated with medication or electroconvulsive treatment.

According to Dr. Omer Bonne, head of in-patient psychiatry and associate professor at Hadassah-Hebrew University, the scientists found that antidepressant medicines normalized decreased brain blood flow usually seen in patients with depression, while electroconvulsive treatment was associated with additional decreases in blood flow.

The patients' response to two different classes of antidepressant medicines that target different neurotransmitters was associated with a similar improvement in cerebral blood flow, Bonne noted. However, cerebral blood flow continued to deteriorate in patients who responded to electroconvulsive therapy, he added.

Additional research could examine whether it's possible to use functional imaging techniques to determine which patients would benefit from drug treatment and which would respond better to electroconvulsive therapy, Bonne said.