CHEST IMAGING WITH DUAL-ENERGY SUBTRACTION DIGITAL TOMOSYNTHESIS

Dual-energy subtraction digital tomosynthesis with pulsed X-ray and ra pid kV switching was used to examine calcifications in pulmonary lesio ns. The digital tomosynthesis system used included a conventional fluo roradiographic TV unit with linear tomographic capabilities, a high re solution videocamera, and an image processing unit. Low-voltage, high- voltage, and soft tissue subtracted or bone subtracted tomograms of an y desired layer height were reconstructed from the image data acquired during a single tomographic swing. Calcifications, as well as their c haracteristics and distribution in pulmonary lesions, were clearly sho wn. The images also permitted discrimination of calcifications from de nse fibrotic lesions. This technique was effective in demonstrating ca lcifications together with a solitary mass or disseminated nodules.