Development of radiation injury of the liver after HDR brachytherapy: (a) Colorectal metastasis in liver segment IV (arrow), T1w-GRE 20 minutes after application of Gd-BOPTA. (b) Contrast-enhanced planning-CT and dosimetry after insertion of brachytherapy catheters (arrow) in the metastasis. The coloured lines indicate different isodoses. Applicated dose at the tumor margin was 20 Gy. (c) MRI after 3 months with a decreased uptake (arrow) of Gd-BOPTA around the irradiated and shrunken metastasis (T1w-GRE 20 minutes after application of Gd-BOPTA).