This site became the new on June 19th. Learn more.
Show more Menu IMPORTANT: Listing of a study on this site does not reflect endorsement by the National Institutes of Health. Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu IMPORTANT: Talk with a trusted healthcare professional before volunteering for a study. Read more... Menu
Give us feedback

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

This study has been completed.
Information provided by:
University Hospital Inselspital, Berne Identifier:
First received: November 15, 2011
Last updated: November 25, 2015
Last verified: November 2015
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 Intervention
Adult Liver Cancer Other: Abdominal surgery

Study Type: Observational
Study Design: Observational Model: Case-Only
Time Perspective: Prospective
Official Title: Accuracy Assessment for Computer-assisted Surgical Interventions of the Liver: A Prospective, Non Randomized Study

Further study details as provided by University Hospital Inselspital, Berne:

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

Enrollment: 14
Study Start Date: October 2011
Study Completion Date: December 2013
Primary Completion Date: December 2013 (Final data collection date for primary outcome measure)
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
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).


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.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: 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
  More Information

Responsible Party: Vanessa Banz/ Prof. Dr. med.Daniel Candinas, Bern University Hospital Identifier: NCT01474694     History of Changes
Other Study ID Numbers: 063/11
Eureka 6201/5/Ae
Study First Received: November 15, 2011
Last Updated: November 25, 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 processed this record on August 18, 2017