Fig 1.
Clinical renal CT slices and distribution of HU values.
(A) Representative clinical axial CT slices of kidney lesion samples in soft tissue window. Aside from the hfAML (venous phase CT) all other scans are unenhanced. The arrows highlight the tumorous tissue. (B) Mean and standard deviation of the quantitative HU values from the images presented in (A). HU: Hounsfield units, mfAML: minimal-fat angiomyolipoma, hfAML: high-fat angiomyolipoma, onco: oncocytoma, ccRCC: clear cell renal cell carcinoma pRCC: papillary renal cell carcinoma, chrRCC: chromophobe renal cell carcinoma.
Fig 2.
Preclinical imaging results of benign kidney lesions in histopathological correlation.
Typical slices of a mfAML, hfAML and oncocytoma (onco) obtained with GBPC-CT, GBAC-CT and T2 fat saturated MRI (MRI T2 fs). The bottom row displays the corresponding histological slices that were obtained for validation with HE-staining. HU: Hounsfield units, HUp: Hounsfield units phase, mfAML: minimal-fat angiomyolipoma, hfAML: high-fat angiomyolipoma, onco: oncocytoma, GBPC-CT: grating-based phase-contrast computed tomography, GBAC-CT: grating-based attenuation-contrast computed tomography, MRI T2 fs: magnetic resonance imaging with T2 fat saturation.
Fig 3.
Preclinical imaging results of renal cell carcinomas in histopathological correlation.
Representative slices of a ccRCC, pRCC and chrRCC obtained with GBPC-CT, GBAC-CT and T2 fat saturated MRI (MRI T2 fs). The bottom row shows the corresponding histological slices that were obtained for validation with HE-staining. HU: Hounsfield units, HUp: Hounsfield units phase, mfAML: minimal-fat angiomyolipoma, hfAML: high-fat angiomyolipoma, ccRCC: clear cell renal cell carcinoma pRCC: papillary renal cell carcinoma, chrRCC: chromophobe renal cell carcinoma, GBPC-CT: grating-based phase-contrast computed tomography, GBAC-CT: grating-based attenuation-contrast computed tomography, MRI T2 fs: magnetic resonance imaging with T2 fat saturation.
Fig 4.
Histogram analysis of quantitative GBPC-CT data.
GBPC-CT signal distribution histograms for the samples presented in Figs 2 and 3. The peak of the mfAML values is quite sharp compared to the other results. The shown range of all histograms is 80 HUp. HU: Hounsfield units, HUp: Hounsfield units phase, mfAML: minimal-fat angiomyolipoma, hfAML: high-fat angiomyolipoma, onco: oncocytoma, ccRCC: clear cell renal cell carcinoma pRCC: papillary renal cell carcinoma, chrRCC: chromophobe renal cell carcinoma, GBPC-CT: grating-based phase-contrast computed tomography.
Fig 5.
Boxplots of HUp and HU results.
Boxplots including all samples of the different tumor subtypes mfAML, oncocytomas (onco), ccRCC, pRCC and chrRCC (n = 26). Mean and standard deviation values for GBPC-CT in HUp (A) and for GBAC-CT in HU (B) are shown here. hfAML samples were excluded for visualization reasons. HU: Hounsfield units, HUp: Hounsfield units phase, mfAML: minimal-fat angiomyolipoma, hfAML: high-fat angiomyolipoma, onco: oncocytoma, ccRCC: clear cell renal cell carcinoma pRCC: papillary renal cell carcinoma, chrRCC: chromophobe renal cell carcinoma, GBPC-CT: grating-based phase-contrast computed tomography, GBAC-CT: grating-based attenuation-contrast computed tomography.
Table 1.
Mean and standard deviation (mean ± std) of the conventional CT number in HU, the phase-contrast CT number in HUp and the electron density ρe for conventional GBAC-CT (HU) and GBPC-CT (HUp and electron density) slices for different types of renal lesions.
HU: Hounsfield units, HUp: Hounsfield units phase, mfAML: minimal-fat angiomyolipoma, hfAML: high-fat angiomyolipoma, onco: oncocytoma, ccRCC: clear cell renal cell carcinoma pRCC: papillary renal cell carcinoma, chrRCC: chromophobe renal cell carcinoma, GBPC-CT: grating-based phase-contrast computed tomography, GBAC-CT: grating-based attenuation-contrast computed tomography.