Figure 3b:
(a) Three-dimensional surface rendering and (b) normal coronary CT angiogram in obese woman (height, 162.6 cm; weight, 94.8 kg; body mass index, 35.9 kg/m2; effective patient diameter, 34.1 cm) imaged at 100-kV tube potential. The more powerful x-ray generator with automated exposure control combined to select a tube potential of 100 kV despite guidelines suggesting 120-kV imaging for patients with a body mass index greater than 30 kg/m2. A tube potential of 100 kV is theoretically better suited for attenuation characteristics of iodinated contrast media and lowers radiation dose compared with 120-kV settings. Estimated effective radiation dose was 0.7 mSv (dose-length product, 48.9 mGy ⋅ cm; CTDIvol, 4.1 mGy; SSDE, 4.3 mGy).