Table 1.
Demographic characteristics.
Table 2.
List of primary tumors.
Fig 1.
Overview of the imaging protocol and timing of each image acquisition.
T1w VIBE = T1-weighted Volume-Interpolated Breath-hold Examination; T2w HASTE = T2-weighted Half Fourier Acquisition Single Shot Turbo Spin Echo; T1w FLASH = T1-weighted Fast Low-angle Shot; T2w TSE = T2-weighted Turbo-spin Echo; DW EPI = Diffusion-weighted Echo-Planar imaging.
Fig 2.
A 25-year-old female patient with a history of colorectal cancer presented multiple liver lesions after surgery.
The FNH in the right liver shows an arterial contrast-agent enhancement (A) and is still hyperintense in the liver-specific contrast phase (C). No significant 18F-FDG-uptake is seen (B, D). A second lesion in the right liver is rated as a colorectal liver metastasis due to incomplete resection. Tumor lesion is neither detectable by MRI without liver-specific contrast phase nor with liver-specific contrast phase (E; G). In fused PET/MR images (F; H) the remaining tumor tissue lesion could clearly be identified. Additional lesions near the liver hilus are adenomas with strong arterial contrast-agent enhancement (I). In the liver-specific contrast phase lesions are hypointense (K). Similar to the FNH, no significant 18F-FDG-uptake is seen (J, L).
Fig 3.
A 61-year-old male patient with liver metastases from a Colorectal Carcinoma.
The large metastasis with intense 18F-FDG-uptake in the right central liver lobe is clearly visible in all datasets (*). The metastasis in the Lobus caudatus does not show increased 18F-FDG-uptake (A, D) and is hardly detectable in the arterial-phase (B) but is clearly detectable as hypointense lesion in the liver-specific phase (C).
Table 3.
Lesion character in benign liver lesions in accordance to reference standard.
Table 4.
PET/MRI with liver specific-contrast phase (PET/MRI2) offers highest accuracy for lesion classification in malignant and benign compared to PET/MRI without liver-specific phase (PET/MRI1) and MRI with (MRI1) and without liver-specific phase (MRI2).
Table 5.
Correct classification of benign lesion in the different modalities in percentage.
Fig 4.
Diagnostic confidence is significantly higher in PET/MRI2 and MRI2 datasets compared to PET/MRI1 and MRI.
Ratings for lesion conspicuity are entered on the y-axis. The vertical bar represents the upper and lower quartiles; the horizontal bar represents the median. The points represent extreme values. Significant differences are marked by a star.