Does dual-energy computed tomography pulmonary angiography (CTPA) have improved image quality over routine...

The aim of this study is to compare the diagnostic sensitivity between dual-energy computed tomography pulmonary angiography (CTPA) studies and routine single-energy CTPA studies.

A total of 117 patients with clinically suspected pulmonary embolism were examined with dual-energy CTPA (DECT) and reformatted single-energy multidetector CTPA (MDCT) studies. Two independent radiologists assessed the image quality of the CTPAs with objective and subjective parameters, including by assigning an image quality score out of 10 for each study. Dose length product and effective dose were also calculated and compared.

The subjective image quality score for DECT and MDCT studies was 9.19 and 7.88, respectively; however, the increased level of detail in DECT may not be clinically applicable. Pulmonary artery filling defects were found in 12 patients, with no subjective diagnostic differences between dual-energy or single-energy studies with either radiologist. The effective dose for DECT ranged from 1.8 to 7.8 mSv. The effective dose for MDCT ranged from 1.2 to 6.4 mSv.

Radiologists are trained to look at routine MDCTs with high specificity and sensitivity. DECTs do not appear to offer trained radiologists improved detection of clinically relevant pulmonary emboli.