Determination of Examination-Specific Diagnostic Reference Level in Computed Tomography by A New Quality...

Area of Science:

• Medical Physics
• Radiological Protection
• Diagnostic Imaging

Background:

• Accurate determination of Diagnostic Reference Levels (DRLs) is crucial for optimizing radiation dose in Computed Tomography (CT).
• Traditional methods for DRL determination can be time-consuming, costly, and disruptive to clinical workflow.

Purpose of the Study:

• To introduce and validate a new Quality-Control (QC)-based dose survey method for CT DRL determination.
• To compare the efficacy of the QC-based method against the conventional data collection method.

Main Methods:

• A retrospective QC-based dose survey method was developed, utilizing data from QC documents and reports.
• The method was applied to 70 CT scanners in Tehran, Iran.
• Results were validated by comparison with a conventional on-site data collection method.

Main Results:

• DRLs for head, sinus, chest, and abdomen/pelvis CT examinations were determined using the QC-based method (CTDIVol: 59, 29, 10, 13 mGy; DLP: 834, 235, 233, 522 mGy-cm).
• The average difference in DRLs between the QC-based and data collection methods was 6.7 ± 5.7%, within IAEA acceptance tolerance.
• The QC-based method demonstrated simplicity, cost-effectiveness, and reduced clinical interruptions.

Conclusions:

• The QC-based dose survey method is an effective and practical alternative for CT DRL determination.
• This method offers significant advantages in terms of efficiency, reduced workload, and potential for large-scale, frequent DRL reviews.