Additional MR Techniques Improve Detection of Pulmonary Embolism
According a study published in the March issue of the journal Radiology, radiologists now have a comparable, non-ionizing option to CT for the detection of pulmonary embolism. The study was led by Diego R. Martin, MD, of the University of Arizona College of Medicine in Tucson. By adding a pair of sequences—volumetric interpolated breath-hold examination (VIBE) and non-contrast true fast imaging with steady-state precession (true FISP)— to previously established MR pulmonary angiography (MRPA) techniques, Martin, et al., found the accuracy of MRPA scans to be improved by as much as 29 percent. In comparing the CT angiography diagnoses of pulmonary embolism in 22 patients, Martin’s group “found a sensitivity of 55 percent, 67 percent and 73 percent for MRPA, true FISP and VIBE, respectively. Combining all three MRI sequences improved the overall detection rate to 84 percent,” said an RSNA press release. The inclusion of VIBE and FISP adds grayscale contrast to MRPA that helps distinguish between the clot and lung, which both seem dark. Additionally, true FISP does not require patients to hold their breath for image acquisition, which Martin said is an additional benefit to the process.