Parametric images for the assessment of cardiac kinetics by magnetic resonance imaging (MRI)

Abstract

The evaluation of Cardiac Magnetic Resonance (CMR) imaging exam is mainly based on the visual aspect. This visual evaluation depends on the level of expertise of the radiologist and it is characterized by variability within and between observers. The aim of this work is to propose a new method based on a mathematical model, "Fourier Transform" which calculates an amplitude parametric image. This image, calculated from the Cine MR images, allows the localization and quantification of abnormalities related to difference in contraction and their extent. The suggested amplitude image is likely to assist in the diagnosis through reducing the time taken by the radiologist to specify the abnormal contraction and by improving the accuracy of the examination. After testing this approach on patients (healthy and pathological), we have proven a good concordance between the results obtained by the parametric image and those collected from the routine examination.

Recent technologies in cardiac imaging

“…MRI is based on the concept a uniform external magnetic field uses radiofrequency energy to align protons in the human body. Fourier transformation is used to relate the frequency information in each imaged plane to corresponding intensity grades, arranged in a matrix of pixels and depicted in shades of grey (42). Tissue is then characterized by longitudinal relaxation time (T1) and transverse relaxation time (T2), defined as the time taken for spinning protons to realign with the magnetic field and the time taken for spinning protons to reach equilibrium; respectively (43).…”