Enhanced visualization of pulmonary perfusion in 4D Dual Energy CT images

Pulmonary embolism (PE) affects up to 600,000 patients and contributes to at least 100,000 deaths every year in the United States alone. Diagnosis of PE can be difficult as most symptoms are unspecific. Computed Tomography (CT) angiography is the reference for diagnosing PE. CT angiography produces grayscale images with darker areas representing any mass filling defects, making the analysis of the images difficult. This article demonstrates a method using the combination of energy levels in Dual Energy CT images to highlight the presence of PE in the lung. The results show that pairing different energy levels from 40 to 140 keV can increase the contrast between well perfused areas and underperfused areas of the lung. In addition, the visualization used in the current study complies with the window/level settings usually employed by radiologists.