New MRI application provides quantitative information about cardiac tissue

Siemens offers a magnetic resonance imaging (MRI) technology that provides radiologists and cardiologists with valuable diagnostic information regarding cardiac tissue condition.

MyoMaps is the world's first MRI application able to provide quantative information regarding the composition of heart muscle tissue and represent changes in such tissues in color in the final image. This can help address so-called diffuse myocardial pathologies, in which the tissue changes are small but distributed over the whole heart. One example is the accumulation of iron deposits in the heart, which can lead to cardiac insufficiency. Siemens recently presented this solution at last year's ESC Congress in Barcelona.

Diffuse Myocardial Pathologies Detected with MyoMaps

MRI examinations are among the best tools available for the diagnosis and treatment of many heart conditions. In simplified terms, an MRI scanner aligns the hydrogen nuclei in a patient's body with the help of powerful magnetic fields, excites these nuclei with radio waves, and then measures the way they resonate. Specifically, the MRI system detects the signals emitted by the nuclei as they resonate. In doing so it can record how many hydrogen nuclei are present at various locations in the body. The decay pattern of the resonance can also be used to make inferences about the properties of the tissue being studied. In the past, typical changes in heart tissue, such as deposits of fat or iron, scarred tissue or edema, were mostly discernible in MRI images after they had already become so extensive as to be pathological.

Creating Images in which Changed Tissue is Displayed in Color

MyoMaps now delivers quantitative information about the tissue composition of the heart muscle and displays them. The technique involves making a very rapid series of MRI images in order to identify the resonance pattern of hydrogen nuclei over time. In order to trace this pattern for each spot in the heart, one must take into account the fact that the beating heart rises and falls within the rib cage during image acquisition.

Siemens Healthcare and experts from Siemens Corporate Technology, have developed sophisticated motion-correction software that can be used to assign an individual pixel to a fixed location during the entire imaging period. Cardiac tissue features can then be determined pixel by pixel. Each pixel is colored according to the result associated with it. Instead of the grayscale images that MRI scanners typically produce, MyoMaps creates images in which changed tissue is displayed in color and thus immediately catches the physician's eye.

MyoMaps was also developed and tested in cooperation with several partners in hospitals. It is currently available for the 1.5 tesla MAGNETOM Area and the 3 tesla MAGNETOM Skyra in combination with the new syngo MR E11 software. Other models are expected to follow.

Provided by Siemens