Fusion of CT Angiography With 3D Contrast Ultrasound as a Method for Follow up for Endovascular Aneurysm Repair

Abdominal Aortic Aneurysm (AAA) is a known vascular entity that may be life threatening condition .The most common treatment approach nowadays is the endovascular approach, a procedure known as endovascular aortic repair (EVAR). The most common procedure related complication is the expansion of the aneurysm from a "feeding vessel", usually a lumbar or intercostal artery. Another known complication is an endoleak from the stentgraft.Today, accepted EVAR follow up protocol consists of one multiple multiphasic CT angiography (CTA) scan, one month after the procedure and ultrasound exams there after . Ultrasonography is a useful method for detection and evaluation of AAA, has no ionizing radiation and is useful for the dynamic estimation of the aortic width in patients post EVAR. However, the sensitivity of ultrasonography solely for detection of endoleaks in post EVAR patients is not high.In recent years, the development of "fusion" applications allows the dual modality merge between ultrasound and CT scans that can be used as follow up examinations of known imaging findings on CT .Another application that had been developed for ultrasound machines is the ability to generate a 3 dimensional (3D) reconstruction which allows more precision. In the recent year the usage of intravenous contrast agent for ultrasonography based on microbubbles (BRACO SONOVIEW) has been approved by the Israeli ministry of health. This contrast agent is not nephrotoxic and the risk for allergic reaction is very low statistically similar to Gadolinium.A 3D contrast enhanced ultrasonography "fused" together with CTA may be a helpfull addition , which lacks radiation and odine contrast reactions and nephrotoxicity ,in the follow up in post EVAR patients , by means of identifing endoleaks at an earlier stage than by ultrasound alone. The purpose of our research is to evaluate the combined modality (fusion of CTA with CEUS) mentioned above in identifing early endoleaks in post EVAR patients and thu