Original researchThe current role of intraoperative ultrasound during the resection of colorectal liver metastases: A retrospective cohort study

•We examine intraoperative ultrasound use for resection of colorectal liver metastases.•IOUS provides information about lesions that can change in the operative plan.•There is a trend toward improved disease free survival in the IOUS group.•Despite improvement in preoperative imaging, IOUS still plays an important role.

IntroductionLiver resections with negative margins improve survival in patients with colorectal liver metastases (CRLM). Intraoperative ultrasound (IOUS) is a valuable tool that gives information about lesions that ultimately changes surgical strategy to ensure complete removal, which subsequently improves disease free survival (DFS).MethodsA retrospective review of patients who underwent a resection for CRLM from 2009 to 2012 was completed to determine the impact of IOUS.ResultsA total of 103 patients had a hepatic resection for CRLM. All patients had preoperative imaging to assist with operative planning. IOUS was performed in 72 cases. Surgical strategy changed in 31 (43.1%) cases with IOUS, compared to three (9.7%) with no IOUS (P < 0.001). A new lesion was detected in 13 (18.1%) of the cases. A higher proportion of nonanatomic liver resections were performed in the IOUS group (N = 27, 37.5%) compared to the non-IOUS group (N = 6, 19.4%) (P = 0.07).ConclusionAchievement of a negative resection margin was comparable between the two groups. However, there was a trend toward improved DFS in the IOUS group. Despite advances in preoperative imaging, IOUS demonstrates utility in providing novel information that allows removal of the entire tumor burden, using parenchymal-preserving techniques when feasible, leading to improved DFS.