Abdominal applications of diffusion-weighted magnetic resonance imaging: Where do we stand

Figure 9 Hepatocellular carcinoma (arrows) on diffusion-weighted image (A) before and (B) after transarterial chemoembolization. A: Hepatocellular carcinoma (HCC) was hyperintense compared with the cirrhotic liver on diffusion weighted image, with an apparent diffusion coefficient (ADC) = 1.41 × 10^-3 mm²/s vs 1.08 × 10^-3 mm²/s for the liver; B: After transarterial chemoembolization, HCC showed a residual area of hyperintense signal (short arrow) with ADC = 1.38 × 10^-3 mm²/s (residual tumor) and a new area of hypointense signal (long arrow) with ADC = 1.87 × 10^-3 mm²/s (coagulation necrosis), indicating a partial response. This finding of necrosis was supported by lack of enhancement on gadolinium-enhanced imaging and confirmed on follow-up studies.