Imaging liver lesions using grating-based phase-contrast computed tomography with bi-lateral filter post-processing.
X-ray phase-contrast imaging shows improved soft-tissue contrast compared to standard absorption-based X-ray imaging. Especially the grating-based method seems to be one promising candidate for clinical implementation due to its extendibility to standard laboratory X-ray sources. Therefore the purpose of our study was to evaluate the potential of grating-based phase-contrast computed tomography in combination with a novel bi-lateral denoising method for imaging of focal liver lesions in an ex vivo feasibility study. Our study shows that grating-based phase-contrast CT (PCCT) significantly increases the soft-tissue contrast in the ex vivo liver specimens. Combining the information of both signals--absorption and phase-contrast--the bi-lateral filtering leads to an improvement of lesion detectability and higher contrast-to-noise ratios. The normal and the pathological tissue can be clearly delineated and even internal structures of the pathological tissue can be visualized, being invisible in the absorption-based CT alone. Histopathology confirmed the presence of the corresponding findings in the analyzed tissue. The results give strong evidence for a sufficiently high contrast for different liver lesions using non-contrast-enhanced PCCT. Thus, ex vivo imaging of liver lesions is possible with a polychromatic X-ray source and at a spatial resolution of ∼100 µm. The post-processing with the novel bi-lateral denoising method improves the image quality by combining the information from the absorption and the phase-contrast images.
Institute of Materials Science, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany ; Physics Department & Institute of Medical Engineering, Technische Universität München, Garching, Germany.
Julia
J
Herzen
Physics Department & Institute of Medical Engineering, Technische Universität München, Garching, Germany.
Marian S
MS
Willner
Department of Radiology, Technische Universität München, Munich, Germany.
Alexander A
AA
Fingerle
Department of Radiology, Technische Universität München, Munich, Germany.
Peter B
PB
Noël
Philips Technologie GmbH, Innovative Technologies, Research Laboratories, Hamburg, Germany.
Thomas
T
Köhler
Institute of Pathology, Technische Universität München, Munich, Germany.
Enken
E
Drecoll
Department of Radiology, Technische Universität München, Munich, Germany.
Ernst J
EJ
Rummeny
Physics Department & Institute of Medical Engineering, Technische Universität München, Garching, Germany.
Franz
F
Pfeiffer
D000230:Adenocarcinoma / Q000000981:diagnostic imaging / Q000473:pathology; D005234:Fatty Liver / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D009362:Neoplasm Metastasis; D011856:Radiographic Image Enhancement / Q000295:instrumentation*; D059629:Signal-To-Noise Ratio; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*