Removing Calcification Artifacts in CAD

Patients with coronary artery disease (CAD) and high vessel calcification are contraindicated for traditional computed tomography (CT) and must undergo catheter-based angiography. Photon-counting CT has the potential to change this paradigm. In this case, a patient with persisting cardiac symptoms received a stent as treatment for severe stenosis. Unfortunately, the patient’s severe degree of CAD with calcifications (Figures 1 and 3) made interpretation challenging. Often, clinicians do not perform high-resolution scans with conventional CT because of the patient radiation dose, and even with increased image resolution, calcification still masks pathologies due to image distortion (so-called “blooming”). After using photon-counting CT (the NAEOTOM Alpha CT scanner from Siemens Healthineers and its PURE Lumen feature¹) to eliminate the calcium and its effects on image reconstruction (Figures 2 and 4), the clinicians were able to determine the underlying pathology and the degree of impaired coronary blood flow.

¹Pure Lumen (Vascular Calcium Removal [VCR]) can be used to measure vessel (eg, coronary) stenoses by removing the contributions of calcium from images, based on a phantom evaluation (Allmendinger et al, Invest Radiol. 2022;57(6):399-405).