Sietske Rozie MD, Presenter: Nothing to Disclose

Philip J. Homburg MD, Abstract Co-Author: Nothing to Disclose

Marcel L. Dijkshoorn ScD, Abstract Co-Author: Nothing to Disclose

Diederik Dippel, Abstract Co-Author: Nothing to Disclose

Aad Van Der Lugt MD, PhD, Abstract Co-Author: Research support, Bayer AG

Normally, carotid arteries show distensibility during the heart cycle. Atherosclerotic disease,even in a first stage, may lead to arterial stiffness and assessment may improve risk prediction. In addition, arterial distensibility may influence image quality due to blurring of the luminal borders. We hypothesize that arterial distensibility can be assessed with the 4D-reconstructed images of an ECG-DSCTA scan.

Six patients (3 male, mean age 60.5±9.0 years, range 51-70) with cerebrovascular symptoms underwent multidetector CTA of the carotid arteries. Scanning was performed on a 64-slice MDSCT scanner (Siemens, SOMATOM definition, Forchheim, Germany). A 4D dataset at every 8% of the cardiac RR interval was reconstructed (13 images of each plane) providing motion visibility and minimal and maximal lumen area of the carotid arteries. Images were analyzed on a dedicated workstation using 3D-analysis software (Siemens, CT workplace/MMWP and InSpace AVA). We used axial MPR images, perpendicular to the central lumen line, to measure lumen area at every 8% of the cardiac cycle in the common carotid artery (CCA) and the internal carotid artery (ICA). We calculated the end-diastolic diameter (D) and the absolute change in diameter (∆D) during systole. Pulse pressure (∆P) was defined as the difference between systolic and diastolic blood pressure. The distensibility coefficient was calculated as: 2(∆D/D)/∆P(10-3kPa).

In all 12 carotid arteries distensibility was detected in the CCA and in the ICA. The distensibility coefficient was 5.6 ± 2.6(10-3 kPa) (range 3.1 -11.2). Lumen area in the CCA in systole was 28 ± 4(range 23-33%) larger than in diastole. Lumen are in the ICA in systole was 29 ± 22 (range 14-63%) larger than in diastole.

Arterial distensibility of the carotid artery can be evaluated with 4D reconstructed data of an ECG-gated DSCTA scan. A significant increase in lumen area occurs during the systole.

Distensibility and arterial stiffness of the carotid artery can now be evaluated by ECG-gated DSCTA. Image quality can be improved by freezing the motion of the carotid arterial wall with ECG-gated DSCTA.

Rozie, S, Homburg, P, Dijkshoorn, M, Dippel, D, Van Der Lugt, A, ECG-gated Dual Source CT Angiography (ECG-DSCTA) Provides 4D-data to Evaluate the Distensibility of Carotid Arteries.  Radiological Society of North America 2007 Scientific Assembly and Annual Meeting, November 25 - November 30, 2007 ,Chicago IL. http://archive.rsna.org/2007/5010737.html