Published online Mar 7, 2020. doi: 10.3748/wjg.v26.i9.960
Peer-review started: November 28, 2019
First decision: December 23, 2019
Revised: January 12, 2020
Accepted: January 19, 2020
Article in press: January 19, 2020
Published online: March 7, 2020
In clinical practice, the diagnosis is sometimes difficult with contrast-enhanced ultrasound (CEUS) when the case has an atypical perfusion pattern. Color parametric imaging (CPI) is an analysis software for CEUS with better detection of temporal differences in CEUS imaging using arbitrary colors. It measures the differences in arrival time of the contrast agent in lesions so that the perfusion features of atypical hemangioma and colorectal cancer liver metastasis can be distinguished.
The motivation of this study was to evaluate the role of CPI in the differential diagnosis of atypical hemangioma from liver metastases and the diagnostic performance by staff and resident radiologists. The patients with atypical hemangioma would be benefited by avoiding invasive test or even surgical resection. Furthermore, a junior radiologist can be more confident in the differential diagnosis of liver lesions by CPI.
To evaluate the role of a novel type of CPI of CEUS in the differential diagnosis of atypical hemangioma from liver metastases in patients with a history of colorectal cancer.
All enrolled patients received ultrasound, CEUS and CPI examinations. Resident and staff radiologists independently and retrospectively reviewed CEUS and CPI images. Two sets of criteria were assigned: (1) Routine CEUS alone; and (2) CEUS and CPI. The diagnostic sensitivity, specificity, accuracy and receiver operating characteristic (ROC) curve of resident and staff radiologists were analyzed.
The following CPI features were significantly different between liver hemangioma and liver metastases analyzed by staff and resident radiologists: Peripheral nodular enhancement (65%-70.0% vs 4.5%-13.6%, P < 0.001, P = 0.001), mosaic/chaotic enhancement (5%-10% vs 68.2%-63.6%, P < 0.001, P < 0.001) and feeding artery (20% vs 59.1-54.5%, P = 0.010, P = 0.021). CPI imaging offered significant improvements in detection rates compared with routine CEUS signs in both resident and staff groups.
CPI could provide specific information on the hemodynamic features of liver lesions and help to differentiate atypical hemangioma from liver metastases, for both staff and resident radiologists. CPI is useful especially for radiologists with less CEUS experience.
In this study, a novel type of color contrast enhanced ultrasound provided supplemental information for differential diagnosis between atypical hemangioma and liver metastasis. This technique is safe and effective in clinical practice. However, to confirm the performance of this new imaging method, studies on a larger sample set are required.