Integration of near-infrared fluorescence imaging and Sonazoid contrast-enhanced ultrasound in laparoscopic resection of colorectal liver metastases: a dual-center retrospective study.

BACKGROUND

Increased emphasis has been placed on the accurate assessment of the number and location of colorectal liver metastases (CRLMs), as well as on the implementation of more flexible and efficient surgical strategies for diverse lesions. This study aimed to evaluate the advantages of near-infrared fluorescence imaging (NIRF) combined with a Sonazoid contrast-enhanced ultrasound (SCEUS)-guided laparoscopic surgical strategy for CRLMs.

METHODS

This article details the comprehensive process of CRLM detection and the surgical approach for various lesions. Additionally, a retrospective analysis of clinical data from 69 patients with CRLM at two Chinese centers between December 2022 and May 2024 was conducted. Statistical comparisons were performed using paired t tests to evaluate the number of lesions detected across multiple imaging modalities. Perioperative short-term outcomes and oncological results were evaluated.

RESULTS

In all, 271 lesions were identified using preoperative EOB-MRI+CT as the reference standard. WL+IOUS and NIRF+SCEUS detected 234 and 285 lesions, respectively. Paired t test analysis revealed that the detection rate of lesions by WL+IOUS was significantly lower than that by EOB-MRI+CT (3.391 vs 3.942, P < 0.01), the detection rate with NIRF+SCEUS was substantially greater than that with WL+IOUS (4.130 vs 3.391, P < 0.01), as, NIRF+SCEUS identified 5/12 "disappearing" lesions (3 NIRF+, 2 SCEUS+) following neoadjuvant therapy, 25 lesions were also detected preoperatively by NIRF+SCEUS but not by WL+IOUS (16 NIRF+, 9 SCEUS+), and an additional 21 lesions were not detected preoperatively (11 NIRF+, 10 SCEUS+). The utilization of NIRF+SCEU resulted in changes to the surgical strategy in 28 patients (40.6%). Intraoperative and postoperative outcomes revealed 6 cases of iatrogenic tumor rupture, 67 cases of R0 resection, 3 cases with Clavien III-IV complications, and no 90-day mortality.

CONCLUSION

NIRF+SCEUS not only improves the number of lesions detected by laparoscopy but also guides the resection of lesions and increases the R0 resection rate. This surgical strategy does not increase postoperative complications or mortality.