{
  "abstract": "Background Photon-counting computed tomography (PCCT) offers the potential for improved CT coronary angiography (CTCA) through enhanced resolution and multi-energy imaging. However, reported radiation doses for CTCA with PCCT vary across studies. This systematic review and meta-analysis were performed to evaluate radiation PCCT doses for CCTA and assess variability across studies.Methods PubMed and Embase were searched to identify studies which used PCCT for CTCA. Radiation dose metrics and demographic characteristics were extracted. Meta-analysis was performed using random effect models.Results A total of 32 studies including 6511 patients were included. Pooled mean age was 67.0 (95% confidence interval [CI] 64.4 to 69.7) years, body mass index was 29.2 (95% CI 25.7 to 32.7) kg/m2 and heart rate was 64.3 (95% CI 62.3 to 66.2) beats per minute. Dose length product (DLP) for CCTA ranged from 7.4 to 736 with a pooled mean of 308.8 (95% CI 229.9 to 387.6) mGy.cm. Effective radiation dose, calculated with a conversion factor of 0.028 mSv/Gy.cm2 was 8.6 (95% CI 6.4 to 10.9) mSv. There was considerable heterogeneity across all analysis (I2 range: 95.5 – 99.3%, p<0.001) (table 1, figure 1).Conclusion Reported radiation dose for CTCA with PCCT in research studies published to date ranged widely and the pooled mean was higher than the national diagnostic reference level for CTCA performed prospectively with padding (280 mGy.cm). These findings highlight the need for standardisation of acquisition protocols and dedicated audits of PCCT in clinical practice. Which of the following best summarises the overall findings of this systematic review and meta-analysis on PCCT-CTCA?A. PCCT-CTCA consistently demonstrates low radiation doses across studies.B. Radiation doses for PCCT-CTCA have minimal variability across studies.C. Reported radiation doses for PCCT-CTCA vary widely across studies, with substantial heterogeneity.D. PCCT-CTCA eliminates the need for radiation dose optimisation.Abstract 27 Figure 1Radiation dose of studies reporting computed tomography coronary angiography with photon counting CTAbstract 27 Table 1Demographic characteristics and radiation doseE. Radiation dose in PCCT-CTCA is independent of acquisition protocols.",
  "authors": [
    {
      "affiliations": [
        "University of Edinburgh"
      ],
      "name": "Krystalina Sim"
    },
    {
      "affiliations": [
        "University of Edinburgh"
      ],
      "name": "Michelle Williams"
    }
  ],
  "title": "27 A systematic review and meta-analysis of radiation exposure for coronary angiography with photon counting computed tomography",
  "uid": "dc4f7a5f-36ee-50c3-bce0-872de98a6f0f"
}