Peter Veendrick MD, Presenter: Nothing to Disclose

Ritse Maarten Mann MD, PhD, Abstract Co-Author: Speakers Bureau, Bayer AG

Carine Van der Vleuten MD, PhD, Abstract Co-Author: Nothing to Disclose

Frederick Jan Anton Meijer MD, Abstract Co-Author: Nothing to Disclose

Dietmar Ulrich MD, PhD, Abstract Co-Author: Nothing to Disclose

Bas Verhoeven MD, PhD, Abstract Co-Author: Nothing to Disclose

Marc Wijnen MD, PhD, Abstract Co-Author: Nothing to Disclose

Wendy Busser MMedSc, Abstract Co-Author: Nothing to Disclose

Frank DeLange PhD, Abstract Co-Author: Nothing to Disclose

Leo Schultze Kool MD, Abstract Co-Author: Nothing to Disclose

Digital subtraction angiography (DSA) is considered the gold standard in evaluating arteriovenous malformations (AVMs). In recent years four-dimensional CT-angiography (4D-CTA) has emerged as a new modality to image vascular anatomy and flow characteristics. The objective of the study was to evaluate the applicability of 4D-CTA in patients with AVMs for treatment planning considering dose and image quality compared to DSA.

In this cohort study 23 4D-CTA scans were obtained in 18 patients from June 2011 to March 2014. All 4D-CTAs were acquired using a 320 detector row CT-scanner (Toshiba Aquilon ONE). Effective dose was calculated using dose-length product and standard dose conversion factors. The angiographies were performed on a high-end angiography system (Philips Alura). Effective dose was calculated using the dose-area product. Alternate reading of the DSA and 4D-CTA images was performed by two experienced observers to assess which modality offered the best diagnostic information. A subjective scale was used to compare the DSA and 4D-CTA images. Additionally, 8 of the 23 4D-CTA scans were recalculated to 10 frames per second (fps) and compared to standard 2 fps 4D-CTAs.  

Diagnostic information and treatment planning using 4D-CTA was superior to DSA in 11 of the 18 patients (61%), equal to DSA in 4 patients (22%) and inferior to DSA in 3 patients (17%). The 8 4D-CTAs with 10 fps provided better evaluation of the AVM in all patients compared to standard 2 fps 4D-CTA. Average effective dose of the 4D-CTAs was 10.17 mSv (1.00-57.2, median 5.53). Average effective dose of the DSAs was 18.3 mSv (0.089-40, median 10.5). The large variance in dose values is caused by the differences in imaged anatomic regions and their differences in conversion factors.  

4D-CTA seems to be a promising new imaging modality to evaluate an AVM. In our opinion 4D-CTA images allow for better treatment planning of the AVM in a majority of patients compared to diagnostic DSA. 4D-CTA recalculated to 10 fps gave more insight into the angio-architecture than a standard 2 fps 4D-CTA. Dose comparison revealed a lower average and median effective dose for 4D-CTA than for DSA.  

4D-CTA scans allow for better treatment planning of the AVM in a majority of patients compared to DSA with lower average effective dose.

Veendrick, P, Mann, R, Van der Vleuten, C, Meijer, F, Ulrich, D, Verhoeven, B, Wijnen, M, Busser, W, DeLange, F, Schultze Kool, L, 4D CTA for the Evaluation of Arteriovenous Malformations – A Pilot Study.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14015001.html