Computerized Medical Imaging and Graphics 36 (2012) 183–203 Contents lists available at SciVerse ScienceDirect Computerized Medical Imaging and Graphics journal homepage: www.elsevier.com/locate/compmedimag Modeling and visualization techniques for virtual stenting of aneurysms and stenoses Jan Egger a,b,c,d,∗ , Stefan Grosskopf b,1 , Christopher Nimsky c,2 , Tina Kapur a,3 , Bernd Freisleben d,4 a Surgical Planning Laboratory, Department of Radiology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA b Department of Computed Tomography, Siemens Healthcare, Forchheim, Germany c Department of Neurosurgery, University of Marburg, Marburg, Germany d Department of Mathematics and Computer Science, University of Marburg, Marburg, Germany article info Article history: Received 8 April 2011 Received in revised form 7 December 2011 Accepted 9 December 2011 Keywords: Virtual stenting Modeling Visualization Aneurysm Stenosis abstract In this work, we present modeling and visualization techniques for virtual stenting of aneurysms and stenoses. In particular, contributions to support the computer-aided treatment of artery diseases – artery enlargement (aneurysm) and artery contraction (stenosis) – are made. If an intervention takes place, there are two different treatment alternatives for this kind of artery diseases: open surgery and minimally invasive (endovascular) treatment. Computer-assisted optimization of endovascular treatments is the main focus of our work. In addition to stent simulation techniques, we also present a computer-aided simulation of endoluminal catheters to support the therapy-planning phase. The stent simulation is based on a three-dimensional Active Contour Method and is applicable to both non-bifurcated (I-stents) and bifurcated stents (Y-stents). All methods are introduced in detail and are evaluated with phantom datasets as well as with real patient data from the clinical routine. Additionally, the clinical prototype that is based upon these methods is described. © 2011 Elsevier Ltd. All rights reserved. 1. Introduction Over the past years, medical image processing has become increasingly important for supporting the different treatment stages of somatic diseases. Medical decisions are assisted by com- puters for diagnosis, monitoring, therapy planning, execution and follow-up examinations. In this work, we discuss computer aided treatment of arterial diseases – artery enlargement (aneurysm) and artery narrowing (stenosis). If an intervention needs to be done, two different treatment alternatives exist for the latter two ∗ Corresponding author at: Department of Radiology, Brigham and Women’s Hos- pital, 75 Francis St., Boston, MA 02115, USA. Tel.: +1 617 732 5014; fax: +1 617 582 6033. E-mail addresses: egger@bwh.harvard.edu, egger@med.uni-marburg.de (J. Egger), stefan.grosskopf@siemens.com (S. Grosskopf), nimsky@med.uni-marburg.de (C. Nimsky), tkapur@bwh.harvard.edu (T. Kapur), freisleb@informatik.uni-marburg.de (B. Freisleben). 1 Department of Computed Tomography, Siemens Healthcare, Siemensstraße 1, 91301 Forchheim, Germany. Tel.: +49 9191 18 9040; fax: +49 9191 18 9990. 2 Department of Neurosurgery, University of Marburg, Baldingerstraße, 35043 Marburg, Germany. Tel.: +49 6421 58 66 447; fax: +49 6421 58 66 415. 3 Department of Radiology, Brigham and Women’s Hospital, 75 Francis St., Boston, MA 02115, USA. Tel.: +1 617 732 5893; fax: +1 617 582 6033. 4 Department of Mathematics and Computer Science, University of Marburg, Hans-Meerwein-Str., 35032 Marburg, Germany. Tel.: +49 6421 28 21 568; fax: +49 6421 28 21 573. arterial diseases: open surgery and minimally invasive (endovas- cular) treatment [1,2]. Computer assisted optimization of endovas- cular treatments is the main focus of our work. For endovascular treatment, it is very important to choose an appropriate prosthesis (stent) based on the patient’s characteristics, specifically the char- acteristics of the artery or arteries to be treated, and to be as precise and as fast as possible. This choice has to be made before the inter- vention takes place (preoperatively), because it is not possible to change the stent during an intervention without an additional open surgery. Two arteries are relevant for our work: the aorta and carotid arteries. The aorta originates from the left ventricle and brings blood to all parts of the body. It is divided into three sections: the ascending aorta, the arch of the aorta and the descending aorta. It has a diameter of about 3 cm and a length of about 30–40 cm. The right and left carotid arteries originate from the arch of the aorta and the brachiocephalic artery, respectively. They are located lat- erally on either side of the neck and supply blood to both the head and the neck. Amongst others, there are two main types of vascu- lar diseases for these arteries: aneurysms and stenoses. Aneurysms are a dilation of a blood vessel caused by changes of the vessel wall. There are true and false aneurysms, and for an abdominal aortic aneurysm (AAA) the risk of rupture is high if the diameter reaches 5.5 cm [3]. In contrast, stenoses are an abnormal narrowing of the vessel which causes a decrease in blood flow. The main risk of a carotid stenosis is stroke that usually occurs due to total arterial 0895-6111/$ – see front matter © 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.compmedimag.2011.12.002