Jeffrey M. C. Lau, MD, PhD, is looking for the future of PET/MR use for cardiac imaging.
“Our research provides the groundwork for future research in cardiac PET/MR imaging,” said Lau, of Washington University in St Louis, via press release. “PET/MR provides powerful cardiac imaging and requires a lower radiation dose than PET/CT. Also, the MRI component, which can be acquired simultaneously, provides excellent heart muscle signal for imaging scar tissue caused by heart attacks. In particular, our group is most interested in applying the PET/MR technology to evaluate the likelihood of arrhythmia or irregular heart beat development in patients who have had heart attacks.”
Lau and his colleagues studied 31 patients who underwent both PET/CT and PET/MR with F-18 FDG injection administered about an hour before PET/CT and two hours before PET/MR. FDG uptake in the myocardium was measured by looking at a cross-section of the left ventricle. The average measurement of FDG uptake in the left ventricle was nearly identical: 4.68 for PET/MR and 4.62 for PET/CT.
“Our hope is that, in the future, PET/MR will become the imaging modality of choice for certain cardiac diseases,” Lau said. “One potential use of cardiac PET/MR is to guide the patient selection process when deciding if patients who have suffered ischemic cardiomyopathy are good candidates for cardiac defibrillator implantation. We hope that a better understanding of the metabolic and anatomic correlation of PET/MR in the myocardial scar and scar border can provide more insight into arrhythmias that lead to sudden cardiac death.”
PET/MR systems were shown as works in progress at the past two RSNA meetings, but research into SPECT/MR systems is even newer. Benjamin M. W. Tsui, PhD, director of the division of medical imaging physics in the department of radiology and a professor of radiology, electrical and computer, biomedical engineering, and environmental health sciences at Johns Hopkins University in Baltimore, also shared research on his institution’s work, introducing SPECT/MR.
SPECT/MR allows hybrid imaging using biomarkers labeled with a wide range of radionuclides, enabling a variety of potential applications, including imaging for cancer, cardiovascular and neurological diseases, thyroid and other endocrine disorders, trauma, inflammation, and infection.
“We are pioneering simultaneous SPECT and MR imaging technologies now demonstrated in preliminary small animal studies,” Tsui said in a press release announcing the research. “We have been building the technology with our industrial partner, TriFoil Imaging—formerly the preclinical business of Gamma Medica—for the past five years and have sufficient data now to show that it works. This presents a unique multimodality system that images mice down to a spatial resolution of less than 1 mm at high detection efficiency.”
— Source: SNMMI