Purpose
To evaluate a new iterative reconstruction (IR) algorithm for radiation dose,
image quality (IQ),
signal-to-noise (SNR) and contrast-to-noise ratio (CNR) in multidetector computed tomography (MDCT) dynamic myocardial perfusion imaging (MPI).
Methods and Materials
ECG-gated Myocardial perfusion imaging (MPI) was performed using256-slice MDCT (Brilliance iCT,
Philips Healthcare,
Cleveland,OH) with 8 cm detector without table movement in order to visualise myocardial perfusion deficits in 20 consecutive patients.Perfusion imaging (80 kV,
100 mAs per data set)was arranged during pharmacologicallyinduced stress.
Adenosine infusion (Adenoscan,
Sanofi-Aventis Frankfurt,
Germany) was started at least 3 min beforethe CT examination and continued during the CT data acquisitionat a dose of 240 μg/kg/min.Data acquisition was started intime with application of the contrast agent in order to obtainseveral...
Results
IR improves SNR of normal myocardium (2.8 ± 2.6 with FBP) up to 3.0± 2.2 (IR L1),
3.2± 2.3 (IR L2),
3.4± 2.3 (IR L4),
3.7± 2.1.
(IR L5) and4.1 ± 2.2 (IR L6) Fig. 1 and for the ischemic myocardium (0.7 ± 1.5 with FBP) up to 0.7± 1.3 (IR L2),
0.7± 1.4 (IR L2),
0.8± 1.3 (IR L3),
0.8± 1.4 (IR L4),
0.9± 1.5 (IR L5) and 1.0 ± 1.7 (IR L6) Fig. 2 .
Likewise,
CNR was improved from 2.3 ± 2.1...
Conclusion
Appropriate levels of IR can improve SNR and CNR by a noise reduction of about 30 %.
Thus,
radiation dose may be reduced by appropriate use of IR in dynamic CT-MPI without negative impact on image quality.
References
Gramer BM,
Muenzel D,
Leber V,
von Thaden AK,
Feussner H,
Schneider A,
Vembar M,
Soni N,
Rummeny EJ,
Huber AM (2012) Impact of iterative reconstruction on CNR and SNR in dynamic myocardial perfusion in an animal model.
Eur Radiol 22:2654-61.
Bamberg F,
Becker A,
Schwarz F et al (2011) Detection of hemodynamically
significant coronary artery stenosis: incremental diagnostic
value of dynamic CT-based myocardial perfusion imaging.
Radiology 260:689–698
Mahnken AH,
Brunders P,
Muehlenbruch G et al (2007) Low tube
voltage improves computed tomography imaging of...