Christoph Alexander Karlo MD, Presenter: Nothing to Disclose

Gudrun Feuchtner MD, Abstract Co-Author: Nothing to Disclose

Sebastian Leschka MD, Abstract Co-Author: Nothing to Disclose

Paul Stolzmann MD, Abstract Co-Author: Nothing to Disclose

Hatem Alkadhi MD, Abstract Co-Author: Nothing to Disclose

Stephan Baumueller, Abstract Co-Author: Nothing to Disclose

Lotus May Desbiolles MD, Abstract Co-Author: Nothing to Disclose

Andre Plass, Abstract Co-Author: Nothing to Disclose

Volkmar Falk MD, PhD, Abstract Co-Author: Nothing to Disclose

Olivio Donati MD, Abstract Co-Author: Nothing to Disclose

To evaluate the visualization of the aortic valve-aortic root complex in second-generation dual-source computed tomography angiography (CTA) of the thoracic aorta by prospectively ECG-gated high-pitch, non-gated high-pitch and retrospectively ECG-gated standard-pitch acquisitions.

120 consecutive patients (mean age 68±13 years) were randomly assigned to three different CTA protocols for clinically indicated CTA of the thoracic aorta on a 128-slice dual-source CT system: group A, prospectively ECG-gated high-pitch acquisition (pitch 3.2; n=40); group B, non-gated high-pitch acquisition (pitch 3.2; n=40); group C, retrospectively ECG-gated standard-pitch acquisition (pitch 1.0; n=40). Image quality of the aortic valve, aortic root, and ascending aorta including the coronary ostia was assessed by two independent readers using a 3-point scale. Image noise was measured and estimated effective radiation doses were calculated.

Overall interobserver agreement regarding image quality assessment was good (κ=0.69). Diagnostic image quality of all evaluated structures in 38/40 (80%) patients (group A), 23/40 (58%, group B) and 21/40 (53%, group C). No significant difference in the number of patients with diagnostic image quality among all groups (p=0.56); significantly more patients with excellent image quality in group A compared to groups B and C (each, p<0.01). Average image noise was significantly higher in high-pitch compared to standard-pitch acquisitions (p<0.01). Effective radiation dose in group A (2.4±0.3mSv) was similar to that in group B (2.4±0.3mSV; p=0.73) and significantly lower compared to group C (17.5±4.4mSv; p<0.01).

High-pitch dual-source CTA – either prospectively ECG-gated or non-gated - provides a diagnostic image quality of the aortic valve-aortic root complex that is similar to that of a standard-pitch ECG-gated CTA, but at 86% less radiation dose.

To facilitate CT Angiography of the aortic rott - aortic valve complex at significanly lower radiation dose at diagnostic image quality.

Karlo, C, Feuchtner, G, Leschka, S, Stolzmann, P, Alkadhi, H, Baumueller, S, Desbiolles, L, Plass, A, Falk, V, Donati, O, CT Angiography of the Aortic Valve-Aortic Root Complex: Comparison of High Pitch and Standard Pitch Data Acquisition.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9007762.html