Radiation exposure for coronary artery calcium score at prospective 320 row multi-detector computed tomography
To date there is extensive data on the radiation dose for assessing coronary artery calcium scores (CACS) with 4-64 row multidetector MDCT. However with the advent of 320 row MDCT, the entire heart can be imaged in one beat and thus potentially reduce the radiation dose. The aim of this study was to evaluate radiation dose for CACS on low-dose prospective EKG-triggered 320 row MDCT.
Materials and Methods: Informed consent for this retrospective HIPAA-compliant study was waived and approved by our institution’s institutional review board IRB. One hundred and sixty eight consecutive patients (Male 133 (79%): female 35 (21%), mean body mass index BMI 29±5 and mean heart rate 58± bpm) underwent coronary calcium scoring with prospective gating. The scan parameters were 300 mA, 120 kVp, volume scan length (VSL) 160 mm, gantry rotation 0.350 msec and 320 x 0.5 mm detectors at 320 MDCT. Beta blockers were given to patients in a case heart rate HR > 65 bpm. The effective dose (ED) estimates were calculated for all patients from the dose length product and the conversion factor k (0.014 mSv/mGy/cm) as recommended by current guidelines.
Results: The mean SD radiation was 1.89±0.79 mSv. Overall the range varied from 0.28-2.48 mSv. The radiation was significantly less in females as compared to males (2.02±0.73 vs. 1.41±0.87, p<0.0001). No differences were noted whether HR was <60 vs. >=60 bpm (1.87±0.79 vs. 1.77±0.84 mSv, p=0.45). On the other hand a higher radiation was noted among obese individuals as compared to those with BMI<30 (1.84±0.82 vs. 1.91±0.80 mSv, p=0.62).
Conclusion: Radiation dose obtained from 320-MDCT is similar to those obtained with 4-64 row MDCT. Further studies are needed to assess the feasibility of further lowering the tube current and tube voltage.
Cite this article as:
Khosa F, Khan A, Shuaib W, Clouse M, Budoff M, Blankstein R, Nasir K. Radiation exposure for coronary artery calcium score at prospective 320 row multi-detector computed tomography. Int J Cancer Ther Oncol 2013; 1(2):01023.
Schmermund A, Mohlenkamp S, Erbel R. Coronary artery calcium and its relationship to coronary artery disease. Cardiol Clin 2003; 21:521-534.
Frink RJ, Achor RW, Brown AL, Jr., Kincaid OW, Brandenburg RO. Significance of calcification of the coronary arteries. Am J Cardiol 1970; 26:241-247.
Guerci AD, Spadaro LA, Goodman KJ, Lledo-Perez A, Newstein D, Lerner G, et al. Comparison of electron beam computed tomography scanning and conventional risk factor assessment for the prediction of angiographic coronary artery disease. J Am Coll Cardiol 1998; 32:673-679.
Janssen CH, Kuijpers D, Vliegenthart R, Overbosch J, van Dijkman PR, Zijlstra F, et al. Coronary artery calcification score by multislice computed tomography predicts the outcome of dobutamine cardiovascular magnetic resonance imaging. Eur Radiol 2005; 15:1128-1134.
Becker CR, Majeed A, Crispin A, Knez A, Schoepf UJ, Boekstegers P, et al. CT measurement of coronary calcium mass: impact on global cardiac risk assessment. Eur Radiol 2005; 15:96-101.
Haberl R, Becker A, Leber A, Knez A, Becker C, Lang C, et al. Correlation of coronary calcification and angiographically documented stenoses in patients with suspected coronary artery disease: results of 1,764 patients. J Am Coll Cardiol 2001; 37:451-457.
Sarwar A, Shaw LJ, Shapiro MD, Blankstein R, Hoffman U, Cury RC, et al. Diagnostic and prognostic value of absence of coronary artery calcification. JACC Cardiovasc Imaging 2009; 2:675-688.
Budoff MJ, Shaw LJ, Liu ST, Weinstein SR, Mosler TP, Tseng PH, et al. Long-term prognosis associated with coronary calcification: observations from a registry of 25,253 patients. J Am Coll Cardiol 2007; 49:1860-1870.
Budoff MJ, Achenbach S, Blumenthal RS, Carr JJ, Goldin JG, Greenland P, et al. Assessment of coronary artery disease by cardiac computed tomography: a scientific statement from the American Heart Association Committee on Cardiovascular Imaging and Intervention, Council on Cardiovascular Radiology and Intervention, and Committee on Cardiac Imaging, Council on Clinical Cardiology. Circulation 2006; 114:1761-1791.
Agatston AS, Janowitz WR, Hildner FJ, Zusmer NR, Viamonte M, Jr., Detrano R. Quantification of coronary artery calcium using ultrafast computed tomography. J Am Coll Cardiol 1990;15:827-832.
Arad Y, Spadaro LA, Goodman K, Newstein D, Guerci AD. Prediction of coronary events with electron beam computed tomography. J Am Coll Cardiol 2000; 36:1253-1260.
Shaw LJ, Raggi P, Schisterman E, Berman DS, Callister TQ. Prognostic value of cardiac risk factors and coronary artery calcium screening for all-cause mortality. Radiology 2003; 228:826-833.
Becker CR, Kleffel T, Crispin A, Knez A, Young J, Schoepf UJ, et al. Coronary artery calcium measurement: agreement of multirow detector and electron beam CT. AJR Am J Roentgenol 2001; 176:1295-1298.
Becker CR, Jakobs TF, Aydemir S, Becker A, Knez A, Schoepf UJ, et al. Helical and single-slice conventional CT versus electron beam CT for the quantification of coronary artery calcification. AJR Am J Roentgenol 2000; 174:543-547.
Kopp AF, Ohnesorge B, Becker C, Schroder S, Heuschmid M, Kuttner A, et al. Reproducibility and accuracy of coronary calcium measurements with multi-detector row versus electron-beam CT. Radiology 2002; 225:113-119.
Ulzheimer S, Kalender WA. Assessment of calcium scoring performance in cardiac computed tomography. Eur Radiol 2003; 13:484-497.
Stanford W, Thompson BH, Burns TL, Heery SD, Burr MC. Coronary artery calcium quantification at multi-detector row helical CT versus electron-beam CT. Radiology 2004; 230:397-402.
Gerber TC, Carr JJ, Arai AE, Dixon RL, Ferrari VA, Gomes AS, et al. Ionizing radiation in cardiac imaging: a science advisory from the American Heart Association Committee on Cardiac Imaging of the Council on Clinical Cardiology and Committee on Cardiovascular Imaging and Intervention of the Council on Cardiovascular Radiology and Intervention. Circulation 2009; 119:1056-1065.
Kim SM, Chung MJ, Lee KS, Choe YH, Yi CA, Choe BK. Coronary calcium screening using low-dose lung cancer screening: effectiveness of MDCT with retrospective reconstruction. AJR Am J Roentgenol 2008; 190:917-922.
Wagner LK, Eifel PJ, Geise RA. Potential biological effects following high X-ray dose interventional procedures. J Vasc Interv Radiol 1994; 5:71-84.
Rutten A, Krul SP, Meijs MF, de Vos AM, Cramer MJ, Prokop M. Variability of coronary calcium scores throughout the cardiac cycle: implications for the appropriate use of electrocardiogram-dose modulation with retrospectively gated computed tomography. Invest Radiol 2008; 43:187-194.
Malago R, D'Onofrio M, Baglio I, Brunelli S, Tavella D, Beltrame F, et al. Choice strategy of different dose-saving protocols in 64-slice MDCT coronary angiography. Radiol Med 2009; 114:1196-1213.
Husmann L, Herzog BA, Burger IA, Buechel RR, Pazhenkottil AP, von Schulthess P, et al. Usefulness of additional coronary calcium scoring in low-dose CT coronary angiography with prospective ECG-triggering impact on total effective radiation dose and diagnostic accuracy. Acad Radiol 2010; 17:201-206.
Mahnken AH, Wildberger JE, Simon J, Koos R, Flohr TG, Schaller S, et al. Detection of coronary calcifications: feasibility of dose reduction with a body weight-adapted examination protocol. AJR Am J Roentgenol 2003; 181:533-538.
Hunold P, Vogt FM, Schmermund A, Debatin JF, Kerkhoff G, Budde T, et al. Radiation exposure during cardiac CT: effective doses at multi-detector row CT and electron-beam CT. Radiology 2003; 226:145-152.
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