How MRI, imaging contribute to the growth of depression research
Analysis of major depressive disorder (MDD) has proven difficult in a climate where more and more patients are being diagnosed with the condition. But according to research out of China, MRI and its related modalities are doing a lot to help scientists understand the pathology behind MDD.
Junfeng Li, a physician in the radiology department at Heping Hospital of Changzhi Medical College in Shan Xi, China, headed a mini-review of recent findings on the subject, published this week in Current Pharmaceutical Design. In his paper, he and co-author Hui Qiu call MRI an “essential” noninvasive tool for the evaluation of mental disorders.
“MRI enables characterization of brain morphology and function in MDD patients,” Li and Qui said in their report. “Compared to healthy controls, MDD patients have structural changes in certain brain regions such as the prefrontal cortex, cingulate cortex, precuneus, thalamus and hippocampus.”
MRI parameters like region homogeneity (ReHo), functional connectivity, amplitude of low-frequency fluctuation (ALFF) and mean kurtosis are all commonly used to measure abnormal brain functions in these patients, the authors wrote.
The pair said all those factors had meaning in their review, including the fact that abnormal ReHo values can indicate abnormal activity in corresponding regions, emphasizing cognitive susceptibility to depression. Brain dysfunction might also be indicated by normal ALFF or functional ALFF values, Li and Qui said.
The authors also wrote resting-state functional MRI has played a substantial role in MDD research, serving as a modality that can reflect a patient’s natural mental state and help doctors understand the psychological basis of the disease. They said functional connectivity might be a successful neuroimaging marker for investigating brain function in men and women with MDD.
Diffusion tensor imaging (DTI) and magnetic resonance spectroscopy (MRS) can help identify the condition, as well, Li and Qui wrote, because alterations of DTI can reflect white matter damage and MRS abnormalities can indicate abnormal metabolism. Still, the authors said, before anything can be said conclusively, more research needs to be done on the link between abnormal changes and clinical symptoms. Multicenter trials and longitudinal dynamic tracking surveys, therefore, are needed.
After graduating from Indiana University-Bloomington with a bachelor’s in journalism, Anicka joined TriMed’s Chicago team in 2017 covering cardiology. Close to her heart is long-form journalism, Pilot G-2 pens, dark chocolate and her dog Harper Lee.