[Un article de The Conversation écrit par Thaïs Génisson – Doctorante en bioimagerie, Université de Bordeaux – Aurélien Bustin – Professeur Junior en imagerie cardiovasculaire, Université de Bordeaux]
In total, cardiovascular diseases are responsible for around 140,000 dead per year in France and nearly 2 million deaths per year in Europe.
MRI to assess the function and anatomy of the heart
MRI (magnetic resonance imaging) cardiac is an essential tool in the management of patients with cardiovascular disease. Indeed, this examination allows a complete evaluation of the function and anatomy of the beating heart. This medical imaging technique makes it possible to obtain high quality images of the heart in a non -invasive way and without resorting to the use of radiation (unlike the scanner, for example).
However, current cardiac MRI systems are slow, complex and require specialized expertise, both for acquisition and for their analysis, which limits their large -scale adoption.
Why is heart MRI so complex?
If you were informed that you had to undergo a cardiac MRI exam, you are probably curious to know the expected waiting time. You may have heard that the waiting period for a cardiac mRI exam can be quite long, from four to six months. A brief visit to any radiology service can enlighten you on the reasons for this apparently prolonged expectation.
Indeed, the performance of cardiac MRI exams is complex and requires highly qualified specialists to collect and analyze data, as well as total cooperation of patients.
Patients who perform this exam often spend 40 to 60 minutes inside a noisy and imposing machine. It is necessary to hold your breath throughout the exam in order to obtain clear images, without artifacts linked to breathing.
On the medical side, highly qualified radio manipulators plan and meticulously execute the collection of almost 1,000 images per examination. These images vary in terms of contrast and resolution. Planning their acquisition involves taking care of the patient's comfort, his heart rate and his breathing carefully.
Finally, the analysis of these images is also very time -consuming and represents a major issue. Once the images have been collected, radiologists must extract the diagnostic elements. To do this, they devote considerable time by patient to manually annotating the images to precisely locate the heart and the injured tissues in order to identify possible pathologies. Very few tools are available to automate these tasks, which limits their effectiveness and increases the workload of specialists.
A precious technique for the analysis of infarction scars
The strength of cardiac MRI resides, among other things, in its unique capacity to visualize the lesions of the heart. These damaged lesions or tissues in the heart muscle are called scars. These scars are formed when the cells of the heart muscle have been deprived of blood rich in oxygen rich for too long, this is the case as a result of a infarction for example.
The presence, size and location of the scar on heart muscle are key indicators to diagnose structural heart disease. Analysis of the characteristics of the scar is essential for the patient's prognosis and to determine the therapy to follow.
Research has also shown that the extent and heterogeneity of the scar on MRI images can effectively predict cardiac arrhythmias (Severe heart rate disorders in which part of the heart, ventricles or earrings, can no longer contract properly, editor's note), which could improve the prevention of sudden cardiac death, in particular with the use of implantable defibrillators. Finally, visualizing this scar with precision may also make it possible to guide curative treatments applied by catheters.
Despite these promising applications with direct clinical implications, this technology comes up against a contrast problem, sometimes making the visualization of infarction scars difficult. Indeed, the contrast to the bloody interface is under-optimal, because the signals of the blood and the scar have similar light intensities.
The scars located at this interface are more difficult to identify and can, in some cases, be missed by radiologists. This limitation also reduces sensitivity to small scars and compromises the robustness of existing automatic tools for their quantification.
Ultimately, transform the diagnosis with colored precision
By intelligently manipulating MRI physics to capture only the signal of abnormal heart tissue, it is now possible to make all the difference. When this technique is combined with conventional MRI imaging, the result is stunning: the infarction scars come on in the image!
In response to these challenges associated with conventional mirbum images with clear blood, we have introduced mirbus cardiac imagery.
This innovative technique has proven to be effective in patients to reveal the scar motifs which could otherwise be masked by the blood signal, which offers a potential solution to the limits observed in traditional imaging methods.
Tomorrow, automate the characterization of scars thanks to AI
One of the most remarkable aspects of improved color imaging in color is easy visualization and, therefore, the segmentation of scars. We believe that this technique is particularly suitable for automated cartography and quantification of myocardial scars thanks to artificial intelligence.
Indeed, with the complete cancellation of the signals of the blood and healthy myocardium and with a mainly bright scar signal on the images, a robust segmentation and quantification becomes possible.
This would allow a precise location of the scars, a reliable measurement of their thickness and automated 3D modeling of the whole heart. This advance should transform the characterization of myocardial scars into an intelligence process, simple and precise.
With an unwavering passion for local news, Christopher leads our editorial team with integrity and dedication. With over 20 years’ experience, he is the backbone of Wouldsayso, ensuring that we stay true to our mission to inform.
