Dose comparison

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Dose comparison
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259 mA .40 sec 5 251 mA .40 sec 15 251 mA .40
sec 25 251 mA .40 sec 35 281 mA .40 sec 45 475
mA .40 sec 55 612 mA .40 sec 65 613 mA .40 sec
75 613 mA .40 sec 85 446 mA .40 sec 95
EKG dose modulation
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ECG dose modulation

• recent study using 16 slice MDCT with
  retrospective ECG-gating and tube current
  modulation showed 47 dose reductions in CT
  coronary angiography 33
• Average effective doses for males and females
  were 8.1 and 10.9 mSv respectively without and
  4.3 and 5.6 mSv with tube modulation 33.
• Trabold T, Buchgeister M, Kuttner A, et al.
  Estimation of radiation exposure in 16-detector
  row computed tomography of the heart with
  retrospective ECG-gating. Fortschr Rontgenstr
  2003 175 1051-1055.

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prospective gating
step and shoot phase range 70 shorter exposure
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prospective gating axial
retrospective gating helical
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Dose Comparison
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prospective gated axial
retrospective gated helical
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SnapShot Pulse Coronary CTA Dose vs BMI
Distribution123 patients
Dose vs. BMI Distribution
3 exams
34 exams
36 exams
23 exams
4 exams
5.6 mSv
3.5 msv
4.4 msv
6.6 mSv
6.7 mSv
Distribution
Body Mass Index
Courtesy of Dr. Sablayrolles, CCN, France
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Snapshot pulse
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Snapshot pulse