Published online Jun 21, 2026. doi: 10.3748/wjg.v32.i23.117597
Revised: March 1, 2026
Accepted: March 17, 2026
Published online: June 21, 2026
Processing time: 128 Days and 19.2 Hours
Contrast-enhanced ultrasound (CEUS) performed intraoperatively for colorectal cancer liver metastases can detect concealed liver metastases not identified during preoperative examinations or routine intraoperative ultrasound. This capability is critical for determining the appropriate surgical approach.
To explore the advantages of Sonazoid-CEUS (S-CEUS) over gray-scale ultra
We retrospectively reviewed data from 259 patients with CRLM who underwent MWA at the First People’s Hospital of Changde City between June 2020 and December 2023. Intraoperative target lesion localization was performed using GSUS or S-CEUS. Target lesion visibility was scored using a 5-point scale, and visibility differences between GSUS and S-CEUS were compared. The duration of the Kupffer phase for the target lesions was observed, and the effects of MWA performed during the Kupffer phase were evaluated.
Preoperative magnetic resonance imaging (MRI) identified 273 lesions in 259 patients, whereas intraoperative S-CEUS detected 281 lesions, all confirmed as liver metastases via needle biopsy. The target lesion visibility scores were 2.87 ± 1.09 during GSUS scanning and 4.07 ± 0.74 (arterial phase) and 4.31 ± 0.58 (Kupffer phase) during the S-CEUS. The visibility scores in both the arterial and Kupffer phases of S-CEUS were superior to those in GSUS (both P < 0.05). The Kupffer phase of target lesions lasted > 1 hour. In patients with multiple pre-known lesions, all lesions were localized with a single contrast agent injection. Three occult lesions undetected via preoperative imaging were identified during the Kupffer phase. All lesions underwent MWA in the Kupffer phase. Immediate reassessment with repeat Sonazoid injection 15 minutes post-ablation and enhanced MRI at 1 month postoperatively demonstrated complete ablation of all lesions.
During MWA for CRLM, target lesion visibility in both the arterial and Kupffer phases of S-CEUS was superior to that of GSUS, facilitating improved target lesion localization. The Kupffer phase of S-CEUS provided valuable real-time guidance for MWA.
Core Tip: Advances in imaging technology have improved preoperative lesion localization and surgical planning by providing valuable visual references in the surgical treatment for liver metastases from colorectal cancer. However, strategies to better localize occult lesions intraoperatively following chemotherapy warrants further exploration. Sonazoid (Shizhuoan in Chinese) is a contrast agent taken up by Kupffer cells, which could facilitate further localization of hepatic lesions. However, reports on its intraoperative application in China remain limited. This study compared the visualization of target lesions during laparoscopic microwave ablation for colorectal liver metastases using Sonazoid-enhanced contrast-enhanced ultrasound vs gray-scale ultrasound.