Dual-energy CTA iodine maps offer small benefit in diagnosing pulmonary embolism
Dual-energy (DE) CT iodine maps offer a slight benefit when paired with traditional CT angiography images when diagnosing pulmonary embolism (PE), reported researchers in a Sept. 11 Radiology study.
Dual-energy CT angiography allows simultaneous assessment of the pulmonary vascular structure and parenchymal iodine distribution with limited radiation dosage, according to lead author Elizabeth K. Weidman and colleagues. A recent animal study has shown DE CT angiography improved the detection of PEs compared to CT angiography alone,
Larger human studies have not been performed, leading Weidman, with Memorial Sloan-Kettering Cancer Center, and colleagues to retrospectively analyze 1,144 consecutive DE CT angiography exams performed between January and September 2014.
Upon initial review, Weidman et al. found 372 PEs on 147 of the 1,144 angiograms (12.8 percent). After the team analyzed the DE CT iodine map, 27 additional PEs were discovered on 26 of the total CT angiograms.
Of the 27 newly discovered PEs, six were segmental, 21 subsegmental, 24 were occlusive and three were nonocclusive. These specific findings warrant additional study to determine the clinical significance of iodine maps, the team wrote.
Additionally, the team noted 11 of the 1,144 (1 percent) CT angiograms received a new diagnosis of PE after they examined the iodine maps—“only a small difference,” Weidman and colleagues noted.
“The added diagnostic value of DE CT angiography iodine maps for pulmonary embolism is beyond what is currently available with routine CT angiography,” the authors concluded. “Dual-energy CT iodine maps show a small incremental benefit for the detection of occlusive segmental and subsegmental pulmonary emboli.”
Matt joined Chicago’s TriMed team in 2018 covering all areas of health imaging after two years reporting on the hospital field. He holds a bachelor’s in English from UIC, and enjoys a good cup of coffee and an interesting documentary.