Inter- and intra-individual radiation dose variability in oncologic chest and abdominal computed tomography

Area of Science:

• Radiology
• Medical Imaging
• Oncology

Background:

• Computed tomography (CT) is crucial for cancer imaging but leads to cumulative radiation exposure.
• Variability in radiation dose among CT devices and protocols is a concern for patient safety.

Purpose of the Study:

• To assess radiation dose variability in chest and abdominal CT scans for oncologic patients.
• To evaluate the impact of CT device models and protocol standardization on dose variability.
• To identify strategies for reducing radiation exposure in oncologic CT.

Main Methods:

• Retrospective analysis of 42,441 CT scans from 4,986 oncologic patients.
• Extraction of dose metrics (CTDIvol, DLP, SSDE, effective dose) using automated dose monitoring.
• Assessment of inter- and intra-individual radiation dose variability across different CT devices and protocols.

Main Results:

• Significant radiation dose variations were observed between CT devices (up to 2.4-fold difference).
• Median intra-individual radiation dose variability ranged from 19.8% to 93.7% depending on the scan type.
• Consistent use of the same scanner reduced intra-individual variability significantly (e.g., to 14.7% for non-contrast chest CT).

Conclusions:

• Substantial radiation dose variability persists in oncologic CT, even with standardized protocols.
• Device-specific dose management and consistent scanner utilization are key to improving dose consistency.
• Implementing internal diagnostic reference levels can help minimize radiation exposure in oncologic imaging.