Contrast-enhanced intraoperative ultrasonography equipped with late Kupffer-phase image obtained by sonazoid in patients with colorectal liver metastases

Figure 1 IOUS and CE-IOUS views of a metastasis at the Segment 8. A: The metastatic lesion was unclearly detected as a slightly hypoechoic mass; B: CE-IOUS view of the same lesion. The metastatic lesion was shown as a distinct hypoechoic mass at the late Kupffer-phase.

Figure 2 An occult metastasis. A: An occult metastasis at the segment 4 only detected by CE-IOUS. A clear hypoechoic mass (approximately 6 mm in diameter; black arrow) was newly detected at the delayed Kupffer phase. This metastatic lesion could not be found by CT, MRI, and IOUS. B: Macroscopic view of this metastasis (arrow).

Figure 3 Preoperative CT and SPIO-MRI, and CE-IOUS. A: An enhanced-CT view and an ill-defined low density mass was detected at the segment 7 (arrow); B: A SPIO MRI view and an ill-defined high intensity mass was detected at the segment 8 (arrow); C: CE-IOUS view at the delayed Kupffer phase and a well-demarcated hypoechoic mass was detected by CE-IOUS.

Figure 4 Preoperative CT and SPIO-MRI, and CE-IOUS. A: An enhanced-CT could not detect any lesion at the Segment 6 (arrow); B: A SPIO MRI view could not detect any lesion at the Segment 6 (arrow); C: CE-IOUS view at the delayed Kupffer phase and a small hypoechoic mass partially containing a isoechoic lesion was detected by CE-IOUS.