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Accuracy Assessment for Computer-assisted Surgical Interventions of the Liver (CALS)

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ClinicalTrials.gov Identifier: NCT01474694
Recruitment Status : Completed
First Posted : November 18, 2011
Last Update Posted : November 26, 2015
Information provided by:
University Hospital Inselspital, Berne

Brief Summary:
Preoperative image-guided data correlates with the actual intraoperative reality. Computer-assisted preoperative planning combined with intraoperative mapping of even very small lesions allows for improved accuracy during complete oncological resection / ablation. In the short- and long-term this possibly results in better patient outcome.

Condition or disease Intervention/treatment
Adult Liver Cancer Other: Abdominal surgery

Detailed Description:


The aim of this study is to analyze the available accuracy of a computer-assisted approach to liver surgery and microwave ablation. The term 'computer-assisted' refers to 1) using 3D models of patient anatomy for extended orientation during the planning of the intervention and 2) using an image guidance system (similar to a GPS in a car) that allows for precise targeting of desired anatomical structures (e.g. intrahepatic tumor, bile ducts / vasculature) in the setting of successfully treating liver malignancies. Furthermore, we would like to demonstrate, that image guided open liver surgery is technically feasible, whenever the correlation between preoperative image-guided data and the intraoperative setting can be achieved with a known accuracy.

Eventually, this technology, like in other surgical domains, will lead to successively implemented technical guiding functionalities that could potentially improve patient outcome.


To date, first systems (CE marked medical devices) are available that have been specifically developed for image-guided open liver surgery. The systems tracks positions of surgical instruments in or near the target organs and visualizes the instruments position in correlation to patients medical image data (i.e. 3D-CT) on the computer screen. Surgeons benefit from a view to a virtual scene (on a computer screen) in which CT images, together with models of the vascular structures, tumors and organ boundaries, are intuitively visible. The surgeon can see the moving instrument, just like the movement of a car can be seen in a GPS system


In patients requiring extensive surgery (eg. extended right hemihepatectomy), accurate calculations of the remaining liver volume are essential to avoid postoperative liver failure with potentially serious postoperative complications or even death, resulting from an inadequate remaining liver volume (ie "small-for-size syndrome"). In high-risk liver resections, use of computer programs, such as MeVis (MeVis Medical Solutions Inc.), provide the surgeon with accurate preoperative information, allowing him / her to judge the feasibility of the planned surgical resection based on preoperative liver volume analysis and evaluation of the planned resection line in relation to essential structures (ie. major vessels / bile ducts).

Study Type : Observational
Actual Enrollment : 14 participants
Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Accuracy Assessment for Computer-assisted Surgical Interventions of the Liver: A Prospective, Non Randomized Study
Study Start Date : October 2011
Primary Completion Date : December 2013
Study Completion Date : December 2013

Intervention Details:
    Other: Abdominal surgery
    The patient is placed in a supine position and standard laparotomy (either via subcostal, midline or inverted hockey-stick incision) is performed. After mobilization of the liver, surgical swabs are packed around the organ to prevent unnecessary movement of the liver during the acquisition of the landmarks and the subsequent surgical procedure

Primary Outcome Measures :
  1. TRE, measuring the error in the prediction of a surgical target location when using the navigation system. [ Time Frame: 12 months ]

Secondary Outcome Measures :
  1. 1.Identification of suitable landmarks for registration [ Time Frame: 15 months ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
patients that are still considered unresectable at the time point of presentation

Inclusion Criteria:

  • 1.Written informed consent
  • 2.Male patients and non-pregnant, non-lactating females aged ≥18 years of age (negative serum/urine pregnancy test result at screening)
  • 3.Patients must be candidates for surgical liver resection and/or MWA (at least one anatomical segment) of primary or metastatic liver cancer. The liver tumors must be present on preoperative imaging study (CT and/or MRI).

Exclusion Criteria

  • 1.Any condition which, in the judgment of the clinical investigator or his designee, might increase the risk to the subject or decrease the chance of obtaining satisfactory data to achieve the objectives of the study.
  • 2.A mental condition rendering the patient unable to provide informed consent.
  • 3.Patients with hereditary hematological / coagulation disorders unrelated to their liver disease or cirrhosis of the liver classified as Child's B or C.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01474694

Dep. of visceral and Transplant Surgery, Bern University Hospital
Berne, Switzerland, 3010
Sponsors and Collaborators
University Hospital Inselspital, Berne
Principal Investigator: Vanessa Banz, Dr. med. Bern University Hospital
Principal Investigator: Daniel Candinas, Prof. Dr. med. Bern University Hospital

Responsible Party: Dr.med. Vanessa Banz/ Prof. Dr. med.Daniel Candinas, Bern University Hospital
ClinicalTrials.gov Identifier: NCT01474694     History of Changes
Other Study ID Numbers: 063/11
Eureka 6201/5/Ae
First Posted: November 18, 2011    Key Record Dates
Last Update Posted: November 26, 2015
Last Verified: November 2015

Keywords provided by University Hospital Inselspital, Berne:
prospective study
multicenter trial
analysis, computer assisted image
CE marked
medical devices
catheter ablation

Additional relevant MeSH terms:
Liver Neoplasms
Carcinoma, Hepatocellular
Digestive System Neoplasms
Neoplasms by Site
Digestive System Diseases
Liver Diseases
Neoplasms, Glandular and Epithelial
Neoplasms by Histologic Type