Corporate Research & Development Center

Toshiba, together with Toshiba Medical Systems Corporation, has developed a technology which automatically determines the reference section in 3-D MRI heart images for cardiac diagnoses. Its accuracy was confirmed in cooperation with Kyorin University Hospital. This technology eliminates the complicated procedure of determining the reference cross section at the beginning of cardiac MRI examinations. This new technique is expected to reduce examination time by ten minutes. Our achievement was presented at the 39th Japanese Society for Magnetic Resonance in Medicine (JSMRM), a domestic conference on magnetic reference imaging, and at the 28th European Society for Magnetic Resonance in Medicine and Biology (ESMRMB) in Leipzig, Germany, an international conference, both held in October 2011.

Cardiac MRI allows doctors to simultaneously examine various heart diseases such as ischemic cardiac disease, cardiomyopathy, coronary artery aneurysm, and intra-cardiac thrombus. In most cardiac MRI examinations, the position of a reference cross section is determined first, followed by the imaging of cross sections for diagnosis (reference cross sectional images). The imaging method includes cine imaging sequences to observe the motion of the heart muscle and delayed enhancement imaging to obtain a clear image of how the heart muscle is affected by coronary conditions. The location and inclination of the heart (location of the reference cross section) must be determined for each patient to obtain a collection of reference cross sectional images for examination.

Conventionally, MRI operators had to acquire multiple images to successfully localize the heart, resulting in significant time loss. This repetitive procedure imposed a heavy burden on operators as well as patients, who must hold their breath every time an image is taken. Further, localization is heavily dependent on individual operator skill, so that an accurate reproduction of reference cross sections is difficult to achieve. To address these issues, there has been a demand for an automated cardiac localization technology which includes the automatic determination of the reference cross section. However, the development of such a technique was hindered by inter-patient differences in heart position, size, angle, and image appearance (brightness and contrast) which are also dependent on patient breathing, heartbeat, and disease severity.

Toshiba has developed and successfully automated a knowledge-based cardiac location estimation technology which uses statistical patterns of multiple anatomical areas of the heart extracted from actual case data. This technology allows operators to reliably and accurately determine reference cross sections without having to worry about variations in shape or image appearance. This technology also reduces MRI cardiac examination time, which conventionally took about 50 minutes (40 to 60 minutes), to about 40 minutes.

Toshiba has established a fundamental technology for automatically determining the reference cross section of the heart. This technology has been commercialized as "CardioLine."