Intraoperative hydrocolonic ultrasonography for localization of small colorectal tumors in laparoscopic surgery

Accurate localization of small colorectal cancers and polyps during laparoscopic resection may be difficult and requires precise and reliable localization techniques. This study aimed to assess the usefulness of intraoperative ultrasonography (IOUS) combined with retrograde saline instillation in locating small colorectal cancers and polyps during laparoscopically assisted colectomy.

The study investigated 14 patients with left-sided lesions of the colon and rectum necessitating preoperative marking. During laparoscopically assisted colorectal surgery, the large bowel was filled with saline solution by gravity, then scanned with a 5- to 10-MHz laparoscopic ultrasound probe.

In all patients, both polyps and small cancers were clearly detected by IOUS. Furthermore, the technique was found to be easily mastered and performed. The mean detection time was 11 min. Polyps were seen as hypodense masses protruding from the bowel mucosa, whereas invasive cancers had both hypo- and hyperdense regions with sonographically appreciable penetration through bowel layers.

Intraoperative laparoscopic ultrasonography in conjunction with saline instillation can serve as a useful tool that allows the surgeon to locate small nonpalpable tumors during laparoscopically assisted resection of colorectal cancer.