Advanced image-based virtual monoenergetic dual-energy CT angiography of the abdomen: optimization of kiloelectron volt settings to improve image contrast

Publication

Advanced image-based virtual monoenergetic dual-energy CT angiography of the abdomen: optimization of kiloelectron volt settings to improve image contrast

Journal Paper/Review - Sep 3, 2015

Albrecht Moritz H, Vogl Thomas J, Lehnert Thomas, Bauer Ralf, Bodelle Boris, Fischer Sebastian, Martin Simon S, Kaup Moritz, Bucher Andreas M, Beeres Martin, Hüsers Kristina, Scholtz Jan-Erik, Wichmann Julian L

Citation

Albrecht M, Vogl T, Lehnert T, Bauer R, Bodelle B, Fischer S, Martin S, Kaup M, Bucher A, Beeres M, Hüsers K, Scholtz J, Wichmann J. Advanced image-based virtual monoenergetic dual-energy CT angiography of the abdomen: optimization of kiloelectron volt settings to improve image contrast. Eur Radiol 2015; 26:1863-70.

Type

Journal Paper/Review (English)

Journal

Eur Radiol 2015; 26

Publication Date

Sep 3, 2015

Issn Electronic

1432-1084

Pages

1863-70

Brief description/objective

OBJECTIVES
To compare quantitative image quality parameters in abdominal dual-energy computed tomography angiography (DE-CTA) using an advanced image-based (Mono+) reconstruction algorithm for virtual monoenergetic imaging and standard DE-CTA.

METHODS
Fifty-five patients (36 men; mean age, 64.2 ± 12.7 years) who underwent abdominal DE-CTA were retrospectively included. Mono + images were reconstructed at 40, 50, 60, 70, 80, 90 and 100 keV levels and as standard linearly blended M_0.6 images (60 % 100 kV, 40 % 140 kV). The contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) of the common hepatic (CHA), splenic (SA), superior mesenteric (SMA) and left renal arteries (LRA) were objectively measured.

RESULTS
Mono+ DE-CTA series showed a statistically superior CNR for 40, 50, 60, 70 and 80 keV (P < 0.031) compared to M_0.6 images for all investigated arteries except SMA at 80 keV (P = 0.08). CNR at 40 keV revealed a mean relative increase of 287.7 % compared to linearly blended images among all assessed arteries (P < 0.001). SNR of Mono+ images was consistently significantly higher at 40, 50, 60 and 70 keV compared to M_0.6 for CHA and SA (P < 0.009).

CONCLUSIONS
Compared to linearly blended images, Mono+ reconstructions at low keV levels of abdominal DE-CTA datasets significantly improve quantitative image quality.

KEY POINTS
• Mono+ combines increased attenuation with reduced image noise compared to standard DE-CTA. • Mono+ shows superior contrast-to-noise ratios at low keV compared to linearly-blended images. • Contrast-to-noise ratio in monoenergetic DE-CTA peaks at 40 keV. • Mono+ reconstructions significantly improve quantitative image quality at low keV levels.