Focused radiation hepatitis after Bragg-peak proton therapy for hepatocellular carcinoma: CT findings.

Radiation hepatitis is clearly demonstrated by noncontrast and contrast enhanced CT following radiotherapy for liver diseases. Radiation hepatitis is dependent on dose distribution and is usually demonstrated as a non-segmental bandlike lesion after photon therapy. We report a case of focused, oval-shaped radiation hepatitis that was induced by photon therapy. The attenuation difference was localized in a high-dose area caused by Bragg-peak proton therapy.