Advancing Aortic Dissection Imaging: First Clinical Experience of Photon-Counting CT with Ultra-Fast Spectral...

Area of Science:

• Medical Imaging
• Radiology
• Cardiovascular Imaging

Background:

• Computed tomography (CT) is the gold standard for diagnosing and monitoring aortic dissection (AD).
• Accurate localization of the entry tear and differentiation of true and false lumens are critical.
• Distinguishing post-treatment changes from contrast extravasations requires precise imaging.

Purpose of the Study:

• To evaluate the impact of virtual monoenergetic (VME) reconstructions on contrast enhancement in aortic dissection compartments.
• To compare virtual non-contrast (VNC) images with true non-contrast (NC) images in AD patients.
• To assess the utility of photon-counting detector CT (PCDCT) in AD imaging.

Main Methods:

• Retrospective analysis of PCDCT datasets from 28 AD patients.
• Measurement of attenuation and standard deviation in aorta and false lumen across VME energy levels (40-190 keV).
• Comparison of VME, VNC, and NC reconstructions; calculation of signal-to-noise ratio (SNR); subjective image quality assessment.

Main Results:

• CT values decreased with increasing VME energy levels.
• Ascending aorta demonstrated higher attenuation than descending aorta and false lumen, with differences amplified at lower VME energies.
• SNR was highest for the ascending aorta across all energy levels; VNC and 190 keV VME showed higher CT values than NC, but VNC had worse subjective ratings.

Conclusions:

• Virtual monoenergetic (VME) reconstructions at lower energy levels enhance contrast differentiation in aortic dissection.
• PCDCT offers advanced capabilities for characterizing dissection compartments.
• VME imaging shows promise for improving the diagnostic accuracy of aortic dissection.