Advances in artificial intelligence for imaging-based diagnosis of hepatocellular carcinoma

Table 1 Comparison of major imaging modalities for hepatocellular carcinoma

Modality	Advantages	Limitations
CT	(1) Rapid, whole-liver coverage; (2) High spatial resolution for vascular and calcified structures; and (3) Widely available with standardized interpretation	(1) Ionizing radiation and contrast-related risks; (2) Limited soft-tissue contrast; (3) Lower sensitivity for sub-centimeter lesions; and (4) Susceptible to respiratory artifacts
MRI	(1) Excellent soft-tissue contrast and multi-parametric capability; (2) Specific contrast agents improve HCC detection accuracy; (3) Functional imaging (e.g., DWI, elastography); and (4) No ionizing radiation	(1) Long acquisition time and high cost; (2) Contraindicated for patients with metallic implants; (3) Limited availability; and (4) Less effective in showing calcifications
US	(1) Real-time and dynamic imaging of hepatic blood flow; (2) Useful for biopsy guidance and follow-up; (3) Contrast-enhanced US improves detection of small lesions; and (4) Low cost and radiation-free	(1) Highly operator-dependent; (2) Reduced accuracy in obese patients or with bowel gas; (3) Low sensitivity for sub-centimeter HCC; and (4) Limited for definitive qualitative diagnosis

CT: Computed tomography; MRI: Magnetic resonance imaging; US: Ultrasound; HCC: Hepatocellular carcinoma; DWI: Diffusion-weighted imaging.