Advanced Visualization Techniques for Laparoscopic Liver Surgery
Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
Laparoscopic liver surgery is mainly preferred over the traditional open liver surgery due to its unquestionable benefits. This type of surgery is executed by inserting an endoscope camera and the surgical tools inside the patient’s body through small incisions. The surgeons perform the operation by watching the video transmitted from the endoscope camera to high-resolution monitors. The location of the tumors and cysts is examined before and during the operation by the surgeons from the pre-operative CT scans displayed on a different monitor or on printed copies making the operation more difficult to perform.
In order to make it easier for the surgeons to locate the tumors and cysts and have an insight for the rest of the inner structures of the liver, the 3D models of the liver’s inner structures are extracted from the preoperative CT scans and are overlaid on to the live video stream transmitted from the endoscope camera during the operation, a technique known as virtual X-ray. In that way the surgeons can virtually look into the liver and locate the tumors and cysts (focus objects) and also have a basic understanding of their spatial relation with other critical structures. The current master thesis focuses on enhancing the depth and spatial perception between the focus objects and their surrounding areas when they are overlaid on to the live endoscope video stream. That is achieved by placing a cone on the position of each focus object facing the camera. The cone creates an intersection surface (cut volume) that cuts the structures that lay in it, visualizing the depth of the cut and the spatial relation between the focus object and the intersected structures. The positioning of the cones is calculated automatically according to the center points of the focus objects but the sizes of the cones are user defined with bigger sizes revealing more of the surrounding area. The rest of the structures that are not part of any cut volume are not discarded but handled in such way that still depict their spatial relation with the rest of the structures. Different rendering results are presented for a laparoscopic liver test surgery in which a plastic liver model was used. The results include different presets of the cut volumes’ characteristics. Additionally, the same technique can be applied on the 3D liver’s surface instead of the live endoscope image and provide depth and spatial information. Results from that case are also presented.
Place, publisher, year, edition, pages
2015. , 38 p.
Media and Communication Technology
IdentifiersURN: urn:nbn:se:liu:diva-115727ISRN: LiU-ITN-TEK-A-15/002-SEOAI: oai:DiVA.org:liu-115727DiVA: diva2:796151
Subject / course