Extraction and quantitative analysis of aneurysmal aorta for aiding endovascular stent grafting

Abstract

SUMMARYIn performing interventions including stent grafting, the suitability for stent grafting must be checked and the devices to be used must be designed preoperatively. For these purposes, the three-dimensional shapes of the blood vessels in lesions or the paths of device placement must be measured accurately and quickly. In this paper, a method for measuring the aortal shape from CT angiogram (CTA) and for detecting lesions from the shape characteristics of these is presented. Specifically, this method extracts the blood flow area of the aorta by using a three-dimensional edge-preserving smoothing filter and a region growing method. Extracted blood vessels are classified by using their anatomical characteristics. After initial setting of the medial axis in a blood vessel, it determines the aneurysmal area based on the diameter of the blood vessel and modifies the medial axis. In addition, it detects lesions such as thrombi and calcifications near the blood flow borderline. Application of the method to 30 clinical cases has confirmed that the proposed method is effective in obtaining the shape of blood vessels.

Registration of Preoperative CTA and Intraoperative Fluoroscopic Images for Assisting Aortic Stent Grafting

“…Generation of Digitally Reconstructed Radiograph. First, an aorta region is extracted from CTA using the extraction method which we previously developed [6]. Subsequently, by increasing/decreasing voxel value in aorta region, two kinds of CT data are produced.…”

Opening Ceremony

“…In this group, mainly cardiac images are dealt with. To achieve the purpose, highspeed and cardiac functional imaging technique [11], image registration method, and basic 4D image processing method (extraction, segmentation, quantitative measurement) must be developed [12]. Also methods of modeling time-series of human organs or cardiovascular diseases will be developed.…”