Virtual non-iodine photon-counting CT-angiography for aortic valve calcification scoring

Area of Science:

• Medical Imaging
• Radiology
• Cardiovascular Imaging

Background:

• Photon-counting detector (PCD)-CT enables the creation of virtual non-iodine (VNI) images from contrast-enhanced scans.
• Aortic valve calcification scoring (AVCS) is crucial for assessing cardiovascular risk.

Purpose of the Study:

• To evaluate the diagnostic performance of AVCS derived from VNI datasets generated by a 1st generation clinical dual-source PCD-CT.
• To compare VNI-derived AVCS with traditional true non-contrast (TNC) scans.

Main Methods:

• 123 patients underwent contrast-enhanced, electrocardiogram-gated cardiac CT on a clinical PCD system.
• VNI images were reconstructed at 70 keV using a VNI algorithm.
• True non-contrast (TNC) scans at 70 keV served as the reference standard.

Main Results:

• VNI images demonstrated high diagnostic performance, with sensitivity ranging from 56.0% to 69.2% and specificity of 100% for both prospective and retrospective gating.
• AVCS derived from VNI images showed high correlation with AVCS from TNC scans (r = 0.983-0.986, P < 0.001).
• Subgroup analyses confirmed excellent intra-individual correlation between different acquisition modes.

Conclusions:

• Virtual non-iodine images from cardiac PCD-CT offer excellent diagnostic performance for AVCS.
• The omission of true non-contrast scans may be feasible in the clinical workup of patients with aortic calcifications, streamlining the imaging process.