Boston University researchers have developed a new, \u201cintelligent\u201d metamaterial\u2014which costs less than 10 bucks to build\u2014that could revolutionize magnetic resonance imaging (MRI), making the entire MRI process faster, safer, and more accessible to patients around the world. The technology, which builds on previous metamaterial work by the team, was described in a new paper in <\/a>Advanced Materials<\/a>.<\/em><\/p>\n MRI is used by clinicians to diagnose medical problems by spotting abnormalities that could indicate anything from a torn meniscus to muscular dystrophy. But MRIs are expensive, expose patients to radiation, and they take a long time\u2014often the greater part of an hour for a single scan. Finding enough MRI time for waiting patients can be a problem, even in US hospitals, but in hospitals in countries like India, waiting periods of a year or more can put patients\u2019 lives at risk.<\/p>\n So how do we speed up the MRI process without jeopardizing the quality of imaging? Xin Zhang<\/a>, a BU College of Engineering professor of mechanical engineering and a Photonics Center faculty member, and a team of researchers that includes Boston Medical Center radiologist Stephan Anderson<\/a>, a BU School of Medicine professor of radiology, and Xiaoguang Zhao <\/a>(ENG\u201916), a MED assistant research professor of radiology, are getting creative with metamaterials to solve the problem.<\/p>\n MRI works by generating a powerful magnetic field and sending radio waves into a patient\u2019s body. \u201cAn MRI\u2019s magnetic field is many thousands of times stronger than the Earth\u2019s magnetic field,\u201d says Zhao. \u201cA precisely orchestrated series of higher-energy radio waves are sent into the human body, and the tissues emit lower-energy radio waves that are received by the MRI to produce an image.\u201d<\/p>\n The quality of MRI images depends to a great extent on what\u2019s called signal-to-noise ratio, or SNR. The higher the SNR, the better the image, and the most direct way to improve the SNR is to turn up the magnetic field. Unfortunately, any increase in the magnetic field also increases the complexity and cost of the MRI, as well as potential risks to patients, whose tissue and whose implanted medical devices in particular are literally heated up by the radiation. For that reason, radiologists who would like to get a better look inside a body cannot simply turn up the magnetic field strength.<\/p>\n So Zhang and her collaborators developed a new magnetic metamaterial<\/a> that when placed beside the body part that is the target of a scan boosts the energy emitted by the patient\u2019s body, increasing SNR and improving MRI imaging. The magnetic metamaterial, which is made of simple copper wiring and plastic, was published in <\/a>Nature<\/a><\/em>\u2019s <\/a>Communications Physics<\/a><\/em> in March 2019.<\/p>\n Now, Zhang, Anderson, Zhao, and other team members have taken their development one big step further, developing what they call an \u201cintelligent\u201d metamaterial that selectively boosts the low-energy emissions from the patient\u2019s body and literally turns itself off during the millisecond bursts of high-energy transmission from the machine.<\/p>\n Zhang says that the intelligent metamaterial amplifies SNR by tenfold, which greatly enhances image quality and reduces scan time, opening up a new way to obtain crisper MRI images at very low cost.<\/p>\n \u201cShortening MRI examinations is paramount to maximizing the capacity,\u201d says Anderson. \u201cNot to mention revenue, as well as the overall patient experience of this powerful imaging technology.\u201d<\/p>\n![\"Composite](\"\/eng\/files\/2022\/09\/resized-Onion_image2.jpg\")