Creating flexible MRI technology for children enables improved pediatric care for a broad range of diseases
When children are ill, it’s often difficult for them to communicate the symptoms they’re experiencing. Though medical diagnostics play a critical role in their care, it’s also difficult for children to undergo conventional tests—especially imaging tests—which are primarily optimized for adults. Dr. Shreyas Vasanawala develops safe, definitive, and quantitative diagnostic tests for children. He is particularly focused on making magnetic resonance imaging (MRI) tests child-friendly. Dr. Vasanawala is exploring ways to make MRI fast, tolerant of patient motion, and quantitative in its output. His work will enable a safe technology that is more accessible, cost-effective, and valuable for children, leading to improved pediatric care for a broad range of diseases, including those of the heart, lung, and kidneys, as well as cancers of various organ systems.
Currently, MRI is a lengthy exam with no ionizing radiation that requires a patient to remain motionless in a confined environment. These factors work against a clinician as they attempt to assess a child's health. The most common solution used to help children cooperate is to perform this otherwise very safe test under anesthesia. To circumvent this issue, Dr. Vasanawala and his interdisciplinary research group, which comprises a research associate, three graduate students, and collaborating researchers at Stanford in Electrical Engineering and at University of California, Berkeley, are exploring innovative ways to improve these exams. They want to make the assessment faster and more tolerant to patient motion and lack of cooperativity, as well as enhance the quantitative value of these exams. Dr. Vasanawala and his team have a strong track record of transforming pediatric medical imaging and rapidly taking fundamental advances in mathematics, physics, and engineering into full-scale clinical deployment. Their novel techniques span the whole spectrum of imaging technology, ranging from hardware and data acquisition techniques, to image reconstruction algorithms and algorithms for processing images after they're obtained. Their novel developments have been deployed worldwide to improve child health; for their current projects, they expect significant milestones within two years.
Current Research Includes:
Designing Child-Friendly Imaging Equipment – Current imaging equipment for patients are designed with adults in mind, which can be physically intimidating for children. Confronted with large, sterile pieces of current imaging equipment often intimidates child patients, which leads to a lack of cooperativity. Dr. Vasanwala and his team are working on miniaturizing components of the equipment in order to make them considerably less bulky and physically intimidating. By doing so, their technology will make it much more likely for a child to voluntarily undergo a necessary imaging test.
Designing Speedy Comprehensive Congenital Heart Disease Tests - The conventional MRI currently takes about one hour to complete. It requires the patient to hold their breath, keeping their lungs and heart still so the pictures do not blur. It is very difficult to require a child to hold his or her breath on command for 20-30 seconds, especially when suffering from lung or heart disease. Dr. Vasanawala's and his team are working on a very detailed quantitative MRI assessment of heart anatomy, function, blood flow, and lung function that can be performed in five minutes. Their innovative assessment would be performed in a way that is not traumatic or intimidating for children, allowing young patients to continue breathing normally. Obtaining key quantitative output will be completed within a year, and their long term goal to improve the assessment's speed and comprehension can be realized in three to five years.
Assessing Kidney Function – Current blood tests used to assess a patient's kidney function are often inaccurate and just provide a global metric of kidney function. They do not show whether just one kidney, or even one portion of a kidney, is damaged. Dr. Vasanwala and his team are developing accurate ways to assess kidney function for children in a safe manner, using a personalized medicine approach. The tests they are developing provide regional maps of renal function, enabling a clinician to see, region-by-region, which portion of the kidneys are doing well, and which are not in a much more accurate way than is currently feasible. This will benefit not only children with primary kidney diseases but also those who are on medications for other conditions that damage kidneys or need to be dosed carefully based on kidney function.
Dr. Shreyas Vasanawala has always had a deep passion for advancing pediatric medical diagnosis. Starting with a strong background in mathematics from undergraduate studies at Caltech, he then attended Stanford University for medical school, eventually pursuing his Ph.D. It was during his Ph.D. work that Dr. Vasanwala first worked on imaging techniques. Dr. Vasanawala was initially interested in the many intriguing mathematical problems plaguing that technology. After he finished medical school, having completed a great deal of work in imaging techniques, he decided to pursue a residency in radiology; a natural choice due to his expertise and interest in this area. While in residency, Dr. Vasanawala most enjoyed his pediatric rotations working in the children’s hospital. He became aware of the value of good imaging tests for children, and the significant impact they have on patient’s lives. He then completed a pediatric radiology fellowship and obtained dedicated training at Sick Kids in Toronto, Canada and Cincinnati Children’s, Ohio. He was able to see how various healthcare systems and care models work. Afterwards, he returned to Stanford and opened a lab dedicated to developing new imaging techniques.
Currently, the overwhelming majority of medical imaging development is focused on adults, as that is where the market is. Early in his career, Dr. Vasanawala felt there was much improvement to be made for the development of imaging techniques with kids in mind first. This motivated Dr. Vasanawala to become a pediatric radiologist and pursue those questions in the first place, and he continues to be motivated by the opportunity to improve pediatric diagnostics and address many diseases children face.
In the News
Academy of Radiology Research Distinguished Investigator Award, 2016
System and method providing preamplifier feedback for magnetic reonsnace imaging.
US Patent No. 8,791,696: "System and method providing preamplifier feedback for magnetic reonsnace imaging." Inventors: Grafendorfer T, Calderon PD, Robb F, Tropp JS, Scott GC, Vasanawala SS. Issued 2014.
Comprehensive cardiovascular analysis using phase-contrast MRI of the body.
Japan Patent No.CN103781416B: "Comprehensive cardiovascular analysis using phase-contrast MRI of the body." Inventors: Vasanawala SS, Hsiao A, Alley MT. Issued 2014.
Method of autocalibrating parallel imaging interpolation from arbitrary K-space sampling with noise correlations weighted to reduce noise of reconstructed images.
Coil compression for three dimensional autocalibrating parallel imaging with Cartesian sampling.
US Patent No. 8,538,115: "Coil compression for three dimensional autocalibrating parallel imaging with Cartesian sampling." Inventors: Zhang T, Lustig M, Pauly J, Vasanawala SS. Issued 2013.
Steady state free precession magnetic resonance imaging using phase detection of material separation.
US Patent No. 6,922,054: "Steady state free precession magnetic resonance imaging using phase detection of material separation." Inventors: Vasanawala SS, Hargreaves BA. Issued 2003.
Linear Combination Steady-State Free Precession MRI.
US Patent No. 6,307,368: "Linear Combination Steady-State Free Precession MRI." Inventors: Vasanawala SS, Pauly JM, Nishimura DG. Issued 2001.
Catalyzing the Response to Steady-State in Magnetic Resonance Imaging Sequences.
US Patent No. 6,452,397: "Catalyzing the Response to Steady-State in Magnetic Resonance Imaging Sequences." Inventors: Vasanawala SS, Hargreaves BA, Pauly JM, Nishimura DG. Issued 2001.