A, C, Axial and, B, D, coronal images in a 69-year-old woman with intrahepatic mass-forming cholangiocarcinoma in segment 6 (arrowheads on B and D) who was treated with conventional TACE twice at our institution. The preprocedural T1-weighted MR images are shown with the intraprocedural cone-beam CT (CBCT ) liver perimeter overlay, where the black and white outlines indicate the liver segmentation based on MR and intraprocedural cone-beam CT images, respectively. A, B, Baseline MR images and closed arc cone-beam CT images are shown, and C, D, follow-up MR images and open arc cone-beam CT images are shown. Closed arc cone-beam CT was unable to demonstrate the outer parts of the liver (only 85.4% depiction) and failed to show the entire tumor (arrowheads on B), whereas open arc cone-beam CT covered the complete liver volume and depicted the entire tumor (arrowheads on D).