Laparoscopic ultrasound of the liver

Resection of Colorectal Liver Metastases: Current Perspectives

BACKGROUND

Metastases to the liver is the leading cause of death in patients with colorectal cancer.

METHODS

The authors review the data on diagnosis and management of this clinical problem, and they discuss management options that can be considered.

RESULTS

Complete surgical resection of metastases from colorectal cancer that are localized to the liver results in 5-year survival rates ranging from 26% to 40%.

CONCLUSIONS

By adding modalities such as targeted systemic therapy and other "local" treatments for liver metastases, further gains in survival are anticipated.

Navigated ultrasound in laparoscopic surgery

Laparoscopic surgery is performed through small incisions that limit free sight and possibility to palpate organs. Although endoscopes provide an overview of organs inside the body, information beyond the surface of the organs is missing. Ultrasound can provide real-time essential information of inside organs, which is valuable for increased safety and accuracy in guidance of procedures. We have tested the use of 2D and 3D ultrasound combined with 3D CT data in a prototype navigation system. In our laboratory, micro-positioning sensors were integrated into a flexible intraoperative ultrasound probe, making it possible to measure the position and orientation of the real-time 2D ultrasound image as well as to perform freehand 3D ultrasound acquisitions. Furthermore, we also present a setup with the probe optically tracked from the shaft with the flexible part locked in one position. We evaluated the accuracy of the 3D laparoscopic ultrasound solution and obtained average values ranging from 1.6% to 3.6% volume deviation from the phantom specifications. Furthermore, we investigated the use of an electromagnetic tracking in the operating room. The results showed that the operating room setup disturbs the electromagnetic tracking signal by increasing the root mean square (RMS) distance error from 0.3 mm to 2.3 mm in the center of the measurement volume, but the surgical instruments and the ultrasound probe added no further inaccuracies. Tracked surgical tools, such as endoscopes, pointers, and probes, allowed surgeons to interactively control the display of both registered preoperative medical images, as well as intraoperatively acquired 3D ultrasound data, and have potential to increase the safety of guidance of surgical procedures.

Hypervascular hepatic focal lesions: spectrum of imaging features

Detection and characterization of liver lesions often present a diagnostic challenge to the radiologists. Liver lesions may be classified as hypovascular and hypervascular based on degree of hepatic arterial blood supply. Common hypervascular liver lesions include hemangioma, focal nodular hyperplasia, hepatocellular adenoma, hepatocellular carcinoma, fibrolamellar carcinoma, and metastases from primary tumors such as islet cell tumor, carcinoid, renal cell carcinoma, melanoma, and thyroid carcinoma. In this review article, we discuss the spectrum of imaging features of hypervascular liver lesions.

Imaging the liver

Imaging of the liver is undertaken for the detection and characterization of suspected primary or secondary neoplasms, prior to planning a surgery or chemotherapy pump placement, for assessing treatment response, for evaluating biliary pathology, and for screening for liver neoplasms in high-risk groups. In this article, we review the advantages and disadvantages of various imaging modalities in the evaluation of the liver and formulate guidelines for the imaging of common clinical indications. A brief review of imaging findings in focal and diffuse liver disease is also presented.

Laparoscopic anatomic liver resection

BACKGROUND

Liver resection is reputed to be one of the most difficult procedures embraced in laparoscopy. This report shows that with adequate training, anatomical liver resection including major hepatectomies can be performed.

METHODS

This is a retrospective study.

RESULTS

From 1995 to 2004, among 84 laparoscopic liver resections, 46 (54%) anatomical laparoscopic hepatectomies were performed in our institution by laparoscopy. Nine (20%) patients had benign disease while 37 (80%) had malignant lesions. Among those with malignant lesions, 14 patients had hepatocellular carcinoma (HCC), 18 had colorectal metastasis (CRM), while 5 had miscellaneous tumours. For benign disease, minor (two Couinaud's segments or less) and major anatomic hepatectomies were performed in five and four patients, respectively. For malignant lesions, minor and major anatomic hepatectomies were performed in 15 and 22 patients, respectively. Overall, conversion to laparotomy was necessary in 7 (15%) patients. Blood transfusion was required in five (10%) patients. One patient died of cerebral infarction 8 days after a massive peroperative haemorrhage. The overall morbidity rate was 34% whatever the type of resection. Three patients required reoperation, either for haemorrhage (n=1) and/or biliary leak (n=2). For CRM (n=18), overall and disease-free survival at 24 months (mean follow-up of 17 months) were 100% and 56%, respectively. For HCC (n=14), overall and disease-free survival at 36 months (mean follow-up of 29 months) were 91% and 65%, respectively. No port site metastasis occurred in patients with malignancy.

CONCLUSIONS

After a long training with limited liver resection in superficial segments, laparoscopic anatomical minor and major resections are feasible. Short-term carcinological results seem to be similar to those obtained with laparotomy.