Evidence Hub

Photon-Counting Detector CT for Liver Lesion Detection—Optimal Virtual Monoenergetic Energy for Different Simulated Patient Sizes and Radiation Doses

D. Racine, V. Mergen, A. Viry, T. Frauenfelder, Hatem Alkadhi, V. Vitzthum, A. Euler

Investigative Radiology, 2024

22 citations

Abstract

Objectives The aim of this study was to evaluate the optimal energy level of virtual monoenergetic images (VMIs) from photon-counting detector computed tomography (CT) for the detection of liver lesions as a function of phantom size and radiation dose. Materials and Methods An anthropomorphic abdominal phantom with liver parenchyma and lesions was imaged on a dual-source photon-counting detector CT at 120 kVp. Five hypoattenuating lesions with a lesion-to-background contrast difference of −30 HU and −45 HU and 3 hyperattenuating lesions with +30 HU and +90 HU were used. The lesion diameter was 5–10 mm. Rings of fat-equivalent material were added to emulate medium- or large-sized patients. The medium size was imaged at a volume CT dose index of 5, 2.5, and 1.25 mGy and the large size at 5 and 2.5 mGy, respectively. Each setup was imaged 10 times. For each setup, VMIs from 40 to 80 keV at 5 keV increments were reconstructed with quantum iterative reconstruction at a strength level of 4 (QIR-4). Lesion detectability was measured as area under the receiver operating curve (AUC) using a channelized Hotelling model observer with 10 dense differences of Gaussian channels. Results Overall, highest detectability was found at 65 and 70 keV for both hypoattenuating and hyperattenuating lesions in the medium and large phantom independent of radiation dose (AUC range, 0.91–1.0 for the medium and 0.94–0.99 for the large phantom, respectively). The lowest detectability was found at 40 keV…

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free