What is HeartViewer?

HeartViewer gives you a chance to see how different hearts function.  Pick up a 3D heart model and scan it to see how the movement of the heart and pumping of blood through its chambers varies.  Try to see how different conditions influence heart function and compare with the normal heart.


What is Magnetic Resonance Imaging?

Magnetic Resonance Imaging (MRI) is a technique used in clinics to acquire pictures of the anatomy and function within the body. Cardiac MRI focuses on creating images within the heart and can be used to observe alterations in heart anatomy, structure and motion.  Because of its clear resolution of different tissues, MRI is a popular technique for examining many different cardiovascular conditions.


How does MRI create pictures in the body?

MRI creates pictures in the body by the excitation of protons.  Protons, like a magnet, are polarized making them have a north and south pole.  An MRI machine uses a strong electromagnetic field to orient these proton poles.  Radio waves are then used to resonate protons, changing the orientation of their north and south poles.  Turning off the radio waves, protons release their energy producing a signal that can be measured.  Magnetic field gradients are used to construct a picture in space, changing the background field so that only specific regions will resonate.  Developing a sequence of different gradients and radio wave stimulation protocols, MRI can effectively create pictures within the body.


What can we see with MRI?

Medical imaging physicists had developed a wide range of sequences that manipulate the signals coming from the body, making MRI a powerful tool for looking at the heart.  As changes in tissue composition alter signal returned to a scanner, MRI is capable of clearly distinguishing different tissues types (muscle, organ, fatty tissue) as well as examining its structure and presence of scar and plaques.  MRI sequences have also been developed to sense motion, making them capable of measuring blood flow through the heart chambers.  MRI can even be used to probe the stiffness of tissue!