Abstract
Objectives
To investigate the feasibility of a newly developed noise reduction technique at coronary CT angiography (CTA) that uses multi-phase data-averaging and non-rigid image registration.
Methods
Sixty-five patients underwent coronary CTA with prospective ECG-triggering. The range of the phase window was set at 70–80 % of the R–R interval. First, three sets of consecutive volume data at 70 %, 75 % and 80 % of the R–R interval were prepared. Second, we applied non-rigid registration to align the 70 % and 80 % images to the 75 % image. Finally, we performed weighted averaging of the three images and generated a de-noised image. The image noise and contrast-to-noise ratio (CNR) in the proximal coronary arteries between the conventional 75 % and the de-noised images were compared. Two radiologists evaluated the image quality using a 5-point scale (1, poor; 5, excellent).
Results
On de-noised images, mean image noise was significantly lower than on conventional 75 % images (18.3 HU ± 2.6 vs. 23.0 HU ± 3.3, P < 0.01) and the CNR was significantly higher (P < 0.01). The mean image quality score for conventional 75 % and de-noised images was 3.9 and 4.4, respectively (P < 0.01).
Conclusions
Our method reduces image noise and improves image quality at coronary CTA.
Key Points
• We introduce a new method for image noise reduction at cardiac CT.
• Multiple data acquisitions of an object and their averaging yield lower noise.
• Our method uses multi-phase images reconstructed from unused redundant imaging data.
• It reduces image noise by averaging multi-phase images transformed by non-rigid registration.
• This method achieves a 20 % image noise reduction at cardiac CT.
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Abbreviations
- CNR:
-
Contrast-to-noise ratio
- CTA:
-
Computed tomography angiography
- LCX:
-
Left circumflex coronary artery
- LMA:
-
Left main artery
- RCA:
-
Right coronary artery
References
Raff GL, Gallagher MJ, O'Neill WW, Goldstein JA (2005) Diagnostic accuracy of noninvasive coronary angiography using 64-slice spiral computed tomography. J Am Coll Cardiol 46:552–557
Leschka S, Alkadhi H, Plass A et al (2005) Accuracy of MSCT coronary angiography with 64-slice technology: first experience. Eur Heart J 26:1482–1487
Nikolaou K, Knez A, Rist C et al (2006) Accuracy of 64-MDCT in the diagnosis of ischemic heart disease. AJR Am J Roentgenol 187:111–117
Herzog C, Zwerner PL, Doll JR et al (2007) Significant coronary artery stenosis: comparison on per-patient and per-vessel or per-segment basis at 64-section CT angiography. Radiology 244:112–120
Hausleiter J, Meyer T, Hadamitzky M et al (2006) Radiation dose estimates from cardiac multislice computed tomography in daily practice: impact of different scanning protocols on effective dose estimates. Circulation 113:1305–1310
Hausleiter J, Meyer T, Hermann F et al (2009) Estimated radiation dose associated with cardiac CT angiography. JAMA 301:500–507
Leschka S, Stolzmann P, Schmid FT et al (2008) Low kilovoltage cardiac dual-source CT: attenuation, noise, and radiation dose. Eur Radiol 18:1809–1817
Einstein AJ, Henzlova MJ, Rajagopalan S (2007) Estimating risk of cancer associated with radiation exposure from 64-slice computed tomography coronary angiography. JAMA 298:317–323
Einstein AJ, Elliston CD, Arai AE et al (2010) Radiation dose from single-heartbeat coronary CT angiography performed with a 320-detector row volume scanner. Radiology 254:698–706
Earls JP, Berman EL, Urban BA et al (2008) Prospectively gated transverse coronary CT angiography versus retrospectively gated helical technique: improved image quality and reduced radiation dose. Radiology 246:742–753
Tatsugami F, Matsuki M, Nakai G et al (2012) The effect of adaptive iterative dose reduction on image quality in 320-detector row CT coronary angiography. Br J Radiol 85:e378–e382
Utsunomiya D, Weigold WG, Weissman G, Taylor AJ (2012) Effect of hybrid iterative reconstruction technique on quantitative and qualitative image analysis at 256-slice prospective gating cardiac CT. Eur Radiol 22:1287–1294
Husmann L, Valenta I, Gaemperli O et al (2008) Feasibility of low-dose coronary CT angiography: first experience with prospective ECG-gating. Eur Heart J 29:191–197
Herzog BA, Husmann L, Burkhard N et al (2008) Accuracy of low-dose computed tomography coronary angiography using prospective electrocardiogram-triggering: first clinical experience. Eur Heart J 29:3037–3042
Roobottom CA, Mitchell G, Morgan-Hughes G (2010) Radiation-reduction strategies in cardiac computed tomographic angiography. Clin Radiol 65:859–867
Tatsugami F, Matsuki M, Inada Y et al (2010) Feasibility of low-volume injections of contrast material with a body weight-adapted iodine-dose protocol in 320-detector row coronary CT angiography. Acad Radiol 17:207–211
Hulme KW, Rong J, Chasen B et al (2011) A CT acquisition technique to generate images at various dose levels for prospective dose reduction studies. AJR Am J Roentgenol 196:W144–W151
Li T, Schreibmann E, Thorndyke B et al (2005) Radiation dose reduction in four-dimensional computed tomography. Med Phys 32:3650–3660
Hirai N, Horiguchi J, Fujioka C et al (2008) Prospective versus retrospective ECG-gated 64-detector coronary CT angiography: assessment of image quality, stenosis, and radiation dose. Radiology 248:424–430
Einstein AJ, Moser KW, Thompson RC, Cerqueira MD, Henzlova MJ (2007) Radiation dose to patients from cardiac diagnostic imaging. Circulation 116:1290–1305
Lembcke A, Wiese TH, Schnorr J et al (2004) Image quality of noninvasive coronary angiography using multislice spiral computed tomography and electron-beam computed tomography: intraindividual comparison in an animal model. Investig Radiol 39:357–364
Achenbach S, Giesler T, Ropers D et al (2003) Comparison of image quality in contrast-enhanced coronary-artery visualization by electron beam tomography and retrospectively electrocardiogram-gated multislice spiral computed tomography. Investig Radiol 38:119–128
Achenbach S, Manolopoulos M, Schuhbäck A et al (2012) Influence of heart rate and phase of the cardiac cycle on the occurrence of motion artifact in dual-source CT angiography of the coronary arteries. J Cardiovasc Comput Tomogr 6:91–98
Birnbaum BA, Hindman N, Lee J, Babb JS (2007) Multi-detector row CT attenuation measurements: assessment of intra- and interscanner variability with an anthropomorphic body CT phantom. Radiology 242:109–119
Acknowledgements
The scientific guarantor of this publication is Dr. Kazuo Awai. The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. This study has received funding by a Grant-in-Aid for Scientific Research (C) from the Japanese Ministry of Education, Culture, Sports, Science and Technology (Japan Society for the Promotion of Science, KAKENHI 24591765). No complex statistical methods were necessary for this paper. Institutional review board approval was obtained. Written informed consent was waived by the institutional review board. Methodology: retrospective, diagnostic study, performed at one institution.
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Tatsugami, F., Higaki, T., Nakamura, Y. et al. A new technique for noise reduction at coronary CT angiography with multi-phase data-averaging and non-rigid image registration. Eur Radiol 25, 41–48 (2015). https://doi.org/10.1007/s00330-014-3381-9
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DOI: https://doi.org/10.1007/s00330-014-3381-9