Bipolar Disorder: New MRI Method Provides New Insights
Using an MRI technique known as quantitative high-resolution T1 rho mapping, the researchers also observed that the cerebellar differences were not present in patients taking lithium, the most commonly used treatment for bipolar disorder. This imaging technique is sensitive to certain byproducts of cell metabolism, including levels of glucose and acidity in the brain.
Scientists do not have a good understanding of what causes bipolar disorder, which is characterised by sudden mood shifts from normal to depressed or to an abnormally elevated or "manic" mood state. This psychiatric condition affects about one percent of the population.
The study, published in the journal Molecular Psychiatry, examined 15 patients with bipolar disorder and 25 control subjects matched for age and gender. The bipolar patients were all in normal (euthymic) mood state during the study.
Compared to the brains of people without bipolar disorder, the UI team found that the MRI signal was elevated in the cerebral white matter and the cerebellar region of patients affected by bipolar disorder. The elevated signal may be due to either a reduction in pH or a reduction in glucose concentration, both factors influenced by cell metabolism, said the researchers.
Based on previous research, abnormal cell metabolism may play a role in bipolar disorder. However, investigating metabolic abnormalities in the brain has been hindered by a lack of good imaging tools. Available methods are slow, low-resolution, and require researchers to identify the region of interest at the onset of the study. In contrast, the new MRI imaging technique can rapidly obtain a high-resolution image of the whole brain.
The UI study is the first time the novel MRI technique has been used to investigate a psychiatric disease. "This imaging technique appears to be sensitive to things that just have not been imaged effectively before. So it's really providing a new picture and new insight into the composition and function of the brain [in bipolar disease]," said the study's senior author John Wemmie, MD, PhD, UI professor of psychiatry.
One reason researchers did not know that the cerebellum might be important in bipolar disorder, is because no one chose to look there, noted co-author Casey Johnson, PhD, UI postdoctoral researcher. "Our study was essentially exploratory. We didn't know what we would find. The majority of bipolar disorder research has found differences in the frontal region of the brain. We found focal differences in the cerebellum, which is a region that hasn't really been highlighted in the bipolar literature before."
The finding motivated Johnson and Wemmie to do an extensive search of the scientific literature on bipolar disorder. They began to collect pieces of evidence that suggested that the cerebellum may function abnormally in bipolar disorder and that lithium might potentially target the cerebellum and alter glucose levels in this brain region.
The new insights provided by the T1 rho imaging could help to broaden understanding of the abnormalities that underlie bipolar disease and lead to better ways to diagnose and treat this problem.
Lithium may be an effective mood stabiliser for people with bipolar disorder, but it causes numerous unpleasant side effects for patients. As Dr. Wemmie noted: "If lithium's effect on the cerebellum is the key to its effectiveness as a mood stabiliser, then a more targeted treatment that causes the same change in the cerebellum without affecting other systems might be a better treatment for patients with bipolar disorder."
Source: University of Iowa Health Care
Image Credit: University of Iowa
Published on : Thu, 8 Jan 2015
Print as PDF
Due to the complex nature of the spine, surgeries may be particularly difficult and call for careful preparation for better outcomes. The spineEOS online software provides a 3D visualization of the patient’s spine in its current state as well as a literature-based,...
For users who value state-of-the art technology: Power and flexibility of a PC in a portable ECG Bidirectional Wi-Fi communication Culprit Coronary Artery AlgorithmTM for early STEMI detection The CARDIOVIT FT-1 is ultra-portable:...
The TE7 touch screen ultrasound system is designed to provide superior quality imaging for rapid patient-care decisions. Intuitive gesture controls and efficient focused point-of-care exams minimize the user learning curve, with no need to navigate a...
We recognize that the best chance any patient has at getting better is a clinician at their bedside with all the right answers and the confidence to act. SonoSite education and training is the industry standard – no other point-of-care ultrasound manufacturer...
Based on Mindray's new generation ultrasound platform, mQuadro, M9 has raised the industry standards to an all new level. Advanced signal transmission and reception processors provide highly sensitive and accurate echo detection. Innovative transducer...