In:
European Radiology, Springer Science and Business Media LLC
Kurzfassung:
To investigate photon-counting CT (PCCT)–derived virtual monoenergetic images (VMI) for artifact reduction in patients with unilateral total hip replacements (THR). Methods Forty-two patients with THR and portal-venous phase PCCT of the abdomen and pelvis were retrospectively included. For the quantitative analysis, region of interest (ROI)–based measurements of hypodense and hyperdense artifacts, as well as of artifact-impaired bone and the urinary bladder, were conducted, and corrected attenuation and image noise were calculated as the difference of attenuation and noise between artifact-impaired and normal tissue. Two radiologists qualitatively evaluated artifact extent, bone assessment, organ assessment, and iliac vessel assessment using 5-point Likert scales. Results VMI 110keV yielded a significant reduction of hypo- and hyperdense artifacts compared to conventional polyenergetic images (CI) and the corrected attenuation closest to 0, indicating best possible artifact reduction (hypodense artifacts: CI: 237.8 ± 71.4 HU, VMI 110keV : 8.5 ± 122.5 HU; p 〈 0.05; hyperdense artifacts: CI: 240.6 ± 40.8 HU vs. VMI 110keV : 13.0 ± 110.4 HU; p 〈 0.05). VMI 110keV concordantly provided best artifact reduction in the bone and bladder as well as the lowest corrected image noise. In the qualitative assessment, VMI 110keV received the best ratings for artifact extent (CI: 2 (1–3), VMI 110keV : 3 (2–4); p 〈 0.05) and bone assessment (CI: 3 (1–4), VMI 110keV : 4 (2–5); p 〈 0.05), whereas organ and iliac vessel assessments were rated highest in CI and VMI 70keV . Conclusions PCCT-derived VMI effectively reduce artifacts from THR and thereby improve assessability of circumjacent bone tissue. VMI 110keV yielded optimal artifact reduction without overcorrection, yet organ and vessel assessments at that energy level and higher were impaired by loss of contrast. Clinical relevance statement PCCT-enabled artifact reduction is a feasible method for improving assessability of the pelvis in patients with total hip replacements at clinical routine imaging. Key Points • Photon-counting CT-derived virtual monoenergetic images at 110 keV yielded best reduction of hyper- and hypodense artifacts, whereas higher energy levels resulted in artifact overcorrection. • The qualitative artifact extent was reduced best in virtual monoenergetic images at 110 keV, facilitating an improved assessment of the circumjacent bone. • Despite significant artifact reduction, assessment of pelvic organs as well as vessels did not profit from energy levels higher than 70 keV, due to the decline in image contrast.
Materialart:
Online-Ressource
ISSN:
1432-1084
DOI:
10.1007/s00330-023-09879-4
Sprache:
Englisch
Verlag:
Springer Science and Business Media LLC
Publikationsdatum:
2023
ZDB Id:
1472718-3
