Table 2.
Studies with ultra-low-dose coronary CT angiography with mean effective radiation dose < 2.2 mSv.
| Study | Number of Patients | Heart Rate/bpm | BMI/ kg m-2 | CT Scanner | Dose Reduction | Mean Effective Dose/ mSv | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Yin et al. (2013) [81] | 21 | 50 ± 6 | 23.9 ± 3.2 | 128 detector row, second-generation dual Source CT (Definition Flash, Siemens Healthcare, Forchheim, Germany). | High-pitch spiral acquisition and raw data-based iterative reconstruction. Tube voltage was set to 80 kV and tube current was 50 mAs. | 0.06 ± 0.01 | ||||||||||
| Zhang et al. (2014) [82] | 58 | 60.4 ± 5.7 | 22.5 ± 1.9 | Dual-source CT system (Somatom Flash; Siemens Medical Solutions, Forchheim, Germany). | Prospective ECG-triggered high-pitch spiral acquisition (3.4) at 70 kVp with 30 mL of contrast agent. Automated tube current modulation (CAREDose 4D, Siemens). Image reconstruction with iterative reconstruction SAFIRE (SAFIRE, Siemens, strength-level 3). | 0.17 ± 0.02 | ||||||||||
| Zhang et al. (2016) [83] | 43 | 69.4 ± 13.6 | 23.3 ± 2.8 | 64-slice, second-generation dual-source CT system (Somatom Flash; Siemens Medical Solutions, Forchheim, Germany). | Prospective ECG-triggered high-pitch spiral acquisition (3.4) at 70 kVp. Automated tube current modulation (CAREDose 4D, Siemens) was enabled. | 0.20 ± 0.00 | ||||||||||
| Stehli et al. (2014) [84] | 36 | 57.6 ± 6.2 | 27.6 ± 4.7 | 64-slice CT scanner (Discovery HD 750, GE Healthcare). | Prospective ECG triggering. Body mass index (BMI)–adapted tube voltage and tube current. Images reconstructed using MBIR algorithms. | 0.29 ± 0.12 | ||||||||||
| Hell et al. (2014) [85] | 26 | 54 ± 5 | 27.7 ± 3.8 | 192-slice, third-generation dual-source CT system (Somatom Force; Siemens Healthcare, Forchheim, Germany). | A prospectively ECG-triggered high-pitch (3.2) spiral (flash) acquisition was performed. Tube voltage was set at 70 kVp and tube current at 450 mAs. Images were reconstructed using iterative algorithm ADMIRE (ADMIRE; Siemens Healthcare, Forchheim, strength level 2) |
0.30 ± 0.03 | ||||||||||
| Gordic et al. (2016) [86] | 25* | 61 ± 5 | 25.3 ± 3.4 | 192-slice dual-source CT (SOMATOM Force, Siemens Healthcare). | Prospective ECG-triggered, high-pitch spiral acquisition. Automated attenuation-based tube voltage selection (CAREkV, Siemens) and tube current modulation (CAREDose, Siemens) was applied. In Images reconstructed with ADMIRE (ADMIRE; Siemens Healthcare, Forchheim, strength level 4). | 0.3 ± 0.1 | ||||||||||
| Wang et al. (2012) [69] | 40* | 55.4 ± 4.8 | 20.6 ± 1.4 | Dual source CT scanner (Definition Flash, Siemens AG, Forchheim, Germany). | Prospective ECG-triggering high-pitch spiral (3.4) at 80 kV. | 0.36 ± 0.03 | ||||||||||
| Yin et al. (2013) [81] | 40 | 54 ± 4 | 25.5 ± 3.1 | 64-slice, second-generation dual-source CT system (Somatom Definition Flash, Siemens Healthcare, Forchheim, Germany). | Prospective ECG-triggered high-pitch spiral acquisition (3.4). Attenuation-based tube current modulation (CareDose 4D, Siemens). | 0.58 ± 0.17 | ||||||||||
| Neefjes et al. (2011) [87] |
80* | 58 ± 7 | 28 ± 4 | 64-slice, dual-source CT scanner (Somatom Definition Flash; Siemens Healthcare, Forchheim, Germany). | Prospective ECG-triggered high-pitch spiral (3.4) | 0.81 ± 0.3 | ||||||||||
| Study | Number of Patients | Heart Rate/bpm | BMI/ kg m-2 | CT Scanner | Dose Reduction | Mean Effective Dose/ mSv | ||||||||||
| Achenbach et al. (2010) [70] | 50 | 68 ± 9 | 25.4 ± 4.8 | 128 slice, dual-source CT system (‘Definition Flash’, Siemens Healthcare, Forchheim, Germany) | Prospective ECG-triggered high-pitch spiral acquisition ((pitch was 3.2 in first 28 patients and 3.4 in last 22 patients. Tube voltage was 100 kV and tube current was 320 mA s/rot. | 0.87 ± 0.07 | ||||||||||
| Alkadhi et al. (2010) [30] |
50* | 56 ± 10 | 25.9 ± 2.8 | 128-slice, second-generation dual-source CT scanner (Somatom Definition Flash; Siemens Healthcare, Forchheim, Germany). | Prospectively ECG-gated high-pitch mode (3.4). | 0.9 ± 0.1 | ||||||||||
| Chen et al. (2013) [53] | 107* | 57.1 ± 11.2 | 27.3 (24.6–32.3) | 320 row, second-generation CT scanner (Aquilion One Vision Edition; Toshiba Medical Systems, Otawara, Japan). | Prospectively ECG-gated. Tube potential and tube current were determined with use of automatic exposure control (SURE Exposure3D, Toshiba Medical Systems). Image reconstruction with iterative reconstruction AIDR-3D ((Toshiba Medical Systems). | 0.93 | ||||||||||
| Stolzmann et al. (2011) [42] | 100 | 66 ± 20 | 27.7 ± 4.2 | Second-generation dual-source 128-MDCT CT scanner (Somatom Definition Flash, Siemens Healthcare). | Prospective ECG-triggered high-pitch spiral acquisition (3.4). Tube voltage 100 kVp and tube current-time product 320 mAs per rotation | 1.0 ± 0.2 | ||||||||||
| Lell et al. (2009) [48] | 25 | 69 ± 9 | 26.8 ± 5.6 | 64 detector row, dual source CT system (Definition Flash, Siemens Healthcare, Forchheim, Germany). | Prospective ECG-triggered high-pitch spiral acquisition (3.2). Tube settings were 100 kV/320 mAs and 120 kV/400 mAs for patients below and above 100-kg weight, respectively. | 1.0 ± 0.3 | ||||||||||
| Sun et al. (2012) [57] | 134* | 79 ± 9 | 23.8 ± 2.7 | Second-generation DSCT system (Somatom Definition Flash, Siemens Healthcare, Forchheim, Germany). | Prospective ECG-gated high-pitch spiral acquisition (3.4). Tube voltage 100 kVp and tube current-time product 320 mAs per rotation | 1.04 ± 0.16 | ||||||||||
| Sommer et al. (2010) [49] |
33 | 57.3 ± 7.0 | 24.7 ± 2.0 | Second generation dual source CT scanner (Somatom Definition Flash, Siemens Healthcare). | Prospective ECG-triggered high-pitch spiral acquisition (3.4). | 1.11 ± 0.14 | ||||||||||
| Wang et al. (2014) [80] | 172* | 59.8 ± 7.6 | 24.2 ± 2.5 | Dual-source CT scanner (Somatom Definition Flash; Siemens, Munich, Germany). | Prospective ECG-triggered high-pitch helical mode (flash mode) d if the patient’s HR < 65 bpm and prospectively ECG-triggered sequential mode if the patient’s HR between 65 and 90 bpm. Automatic tube potential selection (CARE kV; Siemens) and automatic tube current selection algorithm (CARE Dose4D; Siemens). | 1.25 ± 1.24 | ||||||||||
| Wichmann et al. (2015) [47] | 25* | 53 ± 2 | … | 128-slice second-generation dual-source CT (Somatom Definition Flash, Siemens Healthcare). | Prosepctive ECG-gated high-pitch spiral. Automatic tube potential selection (CARE kV; Siemens) and automatic tube current selection algorithm (CARE Dose4D; Siemens). | 1.27 ± 0.62 | ||||||||||
| Huang et al. (2015) [34] |
70* | 58.6 ± 4.5 | 24.8 ± 2.8 | 64-slice DSCT scanner (Somatom Definition, Siemens Healthcare, Forchheim, Germany). | Single-phase, prospective ECG-triggered acquisition. | 1.27 ± 0.57 | ||||||||||
| Study | Number of Patients | Heart Rate/bpm | BMI/ kg m-2 | CT Scanner | Dose Reduction | Mean Effective Dose/ mSv | ||||||||||
| Koplay et al. (2016) [88] |
186 | 66.52 ± 11 | 27.97 (19–40) | 128 slice dual-source CT (Somatom Definition Flash, Siemens, Germany). | Prospective ECG-triggered high-pitch spiral acquisition. Automatic tube potential selection (CARE kV; Siemens) and automatic tube current selection algorithm (CARE Dose4D; Siemens). | 1.3 ± 0.4 | ||||||||||
| Leipsic et al. (2011) [64] |
24* | 54 ± 5 | 27 ± 4 | Discovery HD 750 (GE Healthcare, Waukasha, WI, USA). | Prospective ECG-triggering. Reduced tube voltage was defined as 80 or 100 kVp for individuals with BMI < 25 kg/m2 or 25–35 kg/m2, respectively; whereas standard tube voltage was defined as 100 or 120 kVp for individuals with BMI < 25 kg/m2 or 25–35 kg/m2, respectively. | 1.3 ± 0.5 | ||||||||||
| Matsubara et al. (2016) [45] | 17* | 59.1 ± 6.0 | 21.0 ± 2.0 | 128-slice dual-source CT Somatom Definition Flash scanner (Siemens Healthcare) | Prospective ECG-triggered high-pitch spiral acquisition (3.4). | 1.5 ± 0.2 | ||||||||||
| Pflederer et al. (2010) [89] |
56* | … | … | Dual-source CT (Definition, Siemens Healthcare, Forchheim, Germany). | Prospective ECG-triggering. Tube settings were 100 kV/330 mAs. | 1.5 ± 0.4 | ||||||||||
| Mangold et al. (2016) [66] |
43* | 68.1 ± 18.4 | 23.5 ± 3.3 | 3rd generation dual-source CT (Somatom Force, Siemens Healthcare, Forchheim, Germany). | Prospective ECG-triggered spiral acquisition. Automated tube current selection and advanced iterative reconstruction. Tube voltage at 70 kV group. | 1.5 ± 1.2 | ||||||||||
| Kim et al. (2011) [28] | 23* | 59 ± 7 | 24.3 ± 3.5 | 128-slice MDCT (Definition AS Plus 128; Siemens, Forchheim, Germany). | Step-and-shoot prospective ECG-gated group. | 1.75 ± 0.83 | ||||||||||
| Leipsic et al. (2013) [90] |
109* | 59 ± 4 | 27.23 ± 4.27 | Discovery HD 750 (GE Healthcare, Waukasha, WI, USA) and a Toshiba Aquilion One (Toshiba Medical Systems, Tokyo, Japan). | Prospective ECG-triggering with a narrow window acquisition window. | 1.78 | ||||||||||
| Deseive et al. (2015) [46] |
150* | 55.5 ± 5.0 | 26.1 ± 3.5 | Second-generation dual-source CT scanner (Somatom, Definition Flash scanner, Siemens Medical Solutions) | PROTECTION IV study. Prospective ECG-gated high-pitch helical acquisition. 100-kV tube potentials up to a body mass index of 30 kg/m2. | 2.0 ± 2.4 | ||||||||||
| Yoo et al. (2013) [78] | 51 | 55 (39–65) | 25.3 (18.8–32.8) | 640-multi-slice CT scanner (Aquilion ONE; Toshiba Medical Systems, Tochiki-ken, Japan). | Prospective ECG-triggering. Automatic exposure control system (SUREExposure; Toshiba Medical Systems, Tochiki-ken, Japan). Image reconstruction with AIDR-3D (standard). | 2 ± 1 | ||||||||||
| Duarte et al. (2010) [91] |
40* | 60 ± 5 | Weight/kg (70 ± 10) | 128-MDCT (Somatom Definition AS128, Siemens Medical Solutions, Germany). | Prospective ECG-gating with full tube current at 70%. Automated tube current to patient-specific parameters such as size and attenuation of body region (CAREDose system). | 2.1 ± 0.9 | ||||||||||
| Husmann et al. (2009) [92] |
100 | 57 ± 6 | 27 ± 4 | 64-slice, LightSpeed VCT XT scanner (GE Healthcare). | Prospective ECG-triggering. | 2.2 ± 0.7 | ||||||||||