Belgian, French and Italian researchers have developed a new medical imaging technique, a quantitative MRI, which would make it possible to determine more precisely the chances of a patient getting out of a coma. This technique is superior to all other tests used to date.
What to do with a patient in a coma? Should family and doctors continue the care or not? What are the chances that the person will wake up? These questions often cause great dilemma doctors and families alike. Conflicts and dramas also have recently made headlines.
In most cases, the scores to determine the chances of recovery (Glasgow coma scale, EEG…) are rather unreliable and the decision to continue or stop care is based more on the experience of doctors than on a true scientific rationale. Hence the suffering of families related to uncertainty and even conflict.
A quantitative MRI method
A new medical imaging technique, MRI Brain Diffusion Tensor Imaging, combined with the development of disorganization thresholds, would determine whether the person will wake up or not.
The study was published in Lancet Neurology and conducted by a team of Belgian, Italian and French researchers. With this technique, doctors could finally move from the culture of “opinion” to that of “scientific evidence”. An essential element to build trust with families.
The research focused on comas that occur after cardiac arrest, comas fairly consistent in terms of cause and physiopathology. 200 patients participated in the study in centers in Belgium, France and Italy. They were all adults who were in a coma for more than seven days.
A method of analyzing the functioning of the white matter
Using a special MRI technique, scientists have been able to measure the movement of water in the white matter of the brain. The white matter is the material that allows the connection between the neurons themselces, and between the neurons and the rest of the body: it is this substance that conveys information in the brain and is in a way the possibility of circulation of this information in the brain that the researchers measured.
MRI “Brain Diffusion Tensor Imaging” allows to analyze the structure of the white substance and see if the connections are still functional. When the white substance is functioning normally, the MRI sees the movement of the water molecules along the neurons and these molecules all go in the same direction.
From these measurements the researchers have developed an index based on the analysis of the movement of water molecules in the white matter of the brain measured by MRI diffusion tensor between the 7th day and the 28th day after the occurrence of cardiac arrest.
This index measures the level of disorganization of this movement of water molecules to establish thresholds. These thresholds are used to predict with a very high precision the clinical outcome at 6 months of these coma patients.
For researchers, this technique is reliable and above all could help facilitate decision-making in the future, with arguments that really analyze how the brain works.
Louis Puybasset, professor and head of the department of anesthesia-intensive care, at the Pitié Salpêtrière hospital in Paris, directed the study: “Above a certain threshold, we are certain everything will be fine; below, we are sure that it won’t work out well. In the gray zone, you have to wait. ”
A technique superior to all other tests
This technique is an anatomo-physiological measurement that does not fluctuate according to the same researcher. This allows to have evidence of quality and quantity sufficient to decide whether or not the termination of care. “This technique is superior to all other tests used to date,” says Louis Puybasset.
Larger tests, however, need to be conducted to confirm these findings, particularly in coma from other causes, but this technique will help to be more accurate for the suffering families.