Eur Radiol (2007) 17: 1738–1745 DOI 10.1007/s00330-006-0469-x VASCULAR-INTERVENTIONAL Evert F. S. van Velsen Wiro J. Niessen Thomas T. de Weert Cécile de Monyé Aad van der Lugt Erik Meijering Rik Stokking Received: 6 January 2006 Revised: 9 August 2006 Accepted: 28 August 2006 Published online: 1 November 2006 # Springer-Verlag 2006 Evaluation of an improved technique for lumen path definition and lumen segmentation of atherosclerotic vessels in CT angiography Abstract Vessel image analysis is crucial when considering therapeutical options for (cardio-) vascular diseases. Our method, VAMPIRE (Vascular Analysis using Multiscale Paths In- ferred from Ridges and Edges), involves two parts: a user defines a start- and endpoint upon which a lumen path is automatically defined, and which is used for initialization; the automatic segmentation of the vessel lumen on computed tomo- graphic angiography (CTA) images. Both parts are based on the detection of vessel-like structures by analyzing intensity, edge, and ridge information. A multi-observer evaluation study was performed to compare VAMPIRE with a conventional method on the CTA data of 15 patients with carotid artery stenosis. In addition to the start- and endpoint, the two radiologists required on average 2.5 (SD: 1.9) additional points to define a lumen path when using the conventional method, and 0.1 (SD: 0.3) when using VAMPIRE. The segmentation results were quantitatively evaluated using Similarity Indices, which were slightly lower between VAMPIRE and the two radiologists (respectively 0.90 and 0.88) compared with the Similarity Index between the radiologists (0.92). The evaluation shows that the im- proved definition of a lumen path requires minimal user interaction, and that using this path as initialization leads to good automatic lumen seg- mentation results. Keywords Arteries . Spiral computed tomography . Diagnostic imaging . Cardiovascular diseases . Computer-assisted image processing Introduction Cardiovascular diseases and their complications are amongst the major causes of death in the western world. The clinical procedure for these patients calls for accurate vessel description, most notably for (quantitative) diagnosis of stenoses, preoperative planning, and monitoring disease progression or remission. Two-dimensional (2D) digital subtraction angiography (2D-DSA) is still considered the gold standard for vascular visualization and quantification. However, the major drawbacks of 2D-DSA are its invasive nature, which may cause complications during examination [1], and its two-dimensional nature, which may result in overprojection of other vessels and dependence of stenosis measurements on the imaging angle [2]. Three-dimensional rotational angiography (3DRA) [3] overcomes the latter problem, but is still invasive. This explains the increased use of non-invasive and 3D imaging techniques, such as magnetic resonance angiography (MRA) and computed tomographic angiography (CTA) for vascular diagnosis [4]. Measurements of MRA and CTA data are typically per- formed manually, which is time-consuming and user- dependent [5]. The shortcoming of visual assessment of the acquired data has motivated the development of E. F. S. van Velsen . W. J. Niessen (*) . E. Meijering . R. Stokking Departments of Radiology and Medical Informatics, Biomedical Imaging Group Rotterdam, Erasmus MC, University Medical Center Rotterdam, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands e-mail: w.niessen@erasmusmc.nl Tel.: +31-10-4088119 Fax: +31-10-4089447 T. T. de Weert . C. de Monyé . A. van der Lugt Department of Radiology, Erasmus MC, University Medical Center Rotterdam, Dr. Molewaterplein 50, 3015 GE Rotterdam, The Netherlands