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Page 4 of 16 Brunsing et al. Hepatoma Res 2020;6:59 I http://dx.doi.org/10.20517/2394-5079.2020.50

Table 1. AMRI approaches
Sequences Pros Cons
NC-AMRI T1 weighted in-phase and out-of- Cheapest approach Relies on unenhanced imaging
phase Avoids risk of GBCA Heavily dependent on DWI imaging, which
T2 weighted imaging No issues with contrast timing is prone to artifacts in the upper abdomen
Diffusion weighted imaging (DWI) HCC may not exhibit restricted diffusion
Dynamic-AMRI Pre-contrast imaging Allows definitive diagnosis of HCC Inability to detect ancillary features of
Arterial phase imaging Allows diagnosis of tumor in vein HCC
Portal venous phase imaging Cheaper contrast agent options Risk of miscategorization of vascular
Delayed phase imaging pseudolesions
Dependence on contrast timing, thus
repeat imaging requires repeat dose of
GBCA or repeat exam
Requires power injector
HBP-AMRI Hepatobiliary phase imaging High contrast-to-noise Contrast agent is expensive
T2 weighted imaging Contrast material can be hand injected Lesions may be obscured by severe
DWI (optional) in waiting room cirrhosis
Contrast material is retained in the Can detect very early HCCs that cannot
liver for prolonged duration providing a be confirmed with currently available call-
long imaging window and allowing all back tests
sequences to be repeated if necessary
Established scoring system based on
LI-RADS US
AMRI: Abbreviated magnetic resonance imaging; GBCA: gadolinium-based contrast agent; HCC: hepatocellular carcinoma; LI-RADS:
Liver Imaging Reporting and Data System; US: ultrasound; HBP: hepatobiliary phase

A B C

Figure 2. Intralesional fat: 80-year-old male with HCV cirrhosis. Images show a 18 mm observation in the left lobe. The lesion has
ancillary features favoring HCC including mild hyperintense on T2WI (A) as well as intralesional fat in the mass more than adjacent
liver. The latter is characterized by signal drop from In-phase (B) to Out-of-phase (C) images (arrows). HCV: hepatitis C virus; HCC:
hepatocellular carcinoma

mild-to-moderately increased T2 signal, relative to the background liver parenchyma, is more concerning
[38]
for HCC in high-risk patients . T2-weighted imaging may also improve sensitivity by detecting T2-hyper
intense HCC nodules that are difficult to see for various reasons on the other sequences; the incremental
benefit is likely to be modest given the relatively low sensitivity of this sequence for small HCC nodules.

Diffusion weighted imaging
Inclusion of diffusion weighted imaging (DWI) increases sensitivity [39-41] by detecting lesions based on
restricted diffusion, which is thought to reflect hypercellularity. Some DWI features may also be used to
help differentiate HCC from non-HCC malignancy, such as intrahepatic cholangiocarcinoma (iCCA),
2
which often has a more targetoid appearance [42,43] . The highest b-values have ranged from 500-800 s/mm
for NC-AMRI studies.