Radiation exposure during CT-guided biopsies: recent CT machines provide markedly lower doses

Abstract

Objectives

To examine radiation dose levels of CT-guided interventional procedures of chest, abdomen, spine and extremities on different CT-scanner generations at a large multicentre institute.

Materials and methods

1,219 CT-guided interventional biopsies of different organ regions ((A) abdomen (n=516), (B) chest (n=528), (C) spine (n=134) and (D) extremities (n=41)) on different CT-scanners ((I) SOMATOM-Definition-AS+, (II) Volume-Zoom, (III) Emotion6) were included from 2013–2016. Important CT-parameters and standard dose-descriptors were retrospectively examined. Additionally, effective dose and organ doses were calculated using Monte-Carlo simulation, following ICRP103.

Results

Overall, radiation doses for CT interventions are highly dependent on CT-scanner generation: the newer the CT scanner, the lower the radiation dose imparted to patients. Mean effective doses for each of four procedures on available scanners are: (A) (I) 9.3mSv versus (II) 13.9mSv (B) (I) 7.3mSv versus (III) 11.4mSv (C) (I) 6.3mSv versus (II) 7.4mSv (D) (I) 4.3mSv versus (II) 10.8mSv. Standard dose descriptors [standard deviation (SD); CT dose index_vol (CTDI_vol); dose-length product (DLP_body); size-specific dose estimate (SSDE)] were also compared.

Conclusion

Effective dose, organ doses and SSDE for various CT-guided interventional biopsies on different CT-scanner generations following recommendations of the ICRP103 are provided. New CT-scanner generations involve markedly lower radiation doses versus older devices.

Key Points

• Effective dose, organ dose and SSDE are provided for CT-guided interventional examinations.

• These data allow identifying organs at risk of higher radiation dose.

• Detailed knowledge of radiation dose may contribute to a better individual risk-stratification.

• New CT-scanner generations involve markedly lower radiation doses compared to older devices.