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Eur Radiol (2012) 22:26542661 DOI 10.1007/s00330-012-2525-z
CARDIAC
Impact of iterative reconstruction on CNR and SNRin dynamic myocardial perfusion imaging in an animal model
B. M. Gramer & D. Muenzel & V. Leber &
A.-K. von Thaden & H. Feussner & A. Schneider &
M. Vembar & N. Soni & E. J. Rummeny & A. M. Huber
Received: 27 February 2012 /Revised: 20 April 2012 /Accepted: 27 April 2012 /Published online: 3 July 2012 # European Society of Radiology 2012
AbstractObjectives To evaluate a new iterative reconstruction (IR) algorithm for radiation dose, image quality (IQ), signal-to-noise-ratio (SNR), and contrast-to-noise-ratio (CNR) in multidetector computed tomography (MDCT) dynamic myocardial perfusion imaging (MPI).
Methods ECG-gated 256-slice MDCT dynamic MPI was performed in six pigs after subtotal balloon occlusion of one artery. Two 100 kVp protocols were compared: high dose (HD): 150 mAs; low dose (LD): 100 mAs. HD images were reconstructed with filtered back projection (FBP), LD
images with FBP and different strengths of IR (L1, L4, and L7). IQ (5-point scale), SNR, and CNR (ischemic vs. normal myocardium) values derived from the HD (FBP) images and the different LD images were compared.
Results Mean SNR values for myocardium were 16.3, 11.3,13.1, 17.1, and 28.9 for the HD, LD (FBP), LD (L1), LD (L4), and LD (L7) reconstructions, respectively. Mean CNR values were 8.9, 6.3, 7.8, 9.3, and 12.8. IQ was scored as4.6, 3.3, 4.4, 4.7, and 3.4, respectively. A significant loss of IQ was observed for the LD (L7) images compared to the HD (FBP) images (P<0.05).
Conclusion Appropriate levels of iterative reconstruction can improve SNR and CNR, facilitating radiation dose savings in CT-MPI without influencing diagnostic quality.
Key Points Iterative reconstruction (IR) can reduce radiation dose in myocardial perfusion CT.
Our study also demonstrated improvements in image quality (noise, SNR, and CNR).
Dynamic CT-MPI could help determine the hemodynamic significance of coronary artery disease.
With dynamic CT MPI, myocardial blood flow can be determined quantitatively.
Keywords Dynamicmyocardialperfusion .Radiationdose . Iterative reconstruction . MDCT . Ischemia
AbbreviationsCCTA Coronary CT angiography CNR Contrast-to-noise ratioCT Computed tomography
B. M. Gramer (*) : D. Muenzel : V. Leber : E. J. Rummeny :
A. M. HuberInstitut fr Radiologie,Klinikum rechts der Isar der Technischen Universitt Mnchen, Ismaningerstrasse 22,81675 Mnchen, Deutschlande-mail: [email protected]
A.-K....