Radiation dose from Computed Tomography Scanning in Patients at Kantharalak Hospital.

Abstract

  Objective The use of computed tomography (CT) is continuously increasing, which raises concerns about patient radiation dose. For Kantharalak Hospital, there is currently no empirical data on the radiation doses being used. This study's main objective was to evaluate the radiation dose patients receive from CT examinations at Kantharalak Hospital and compare it with Thailand's National Diagnostic Reference Levels (DRLs) for 2025.This was a retrospective descriptive study. Data for the volume CT dose index CTDIvol and dose-length product (DLP) were collected from the PACS dose reports of 180 patients. Patients were over 18 years old, weighed between 47-75 kg, and were scanned between December 1, 2024, and June 30, 2025. The median CTDIvol and DLP for each scan type were analyzed and compared against the national DRLs.Results: The study found that CTDIvol values were mostly consistent with the reference levels. However, the median $DLP$ for several major protocols—namely Brain NC, C, Chest NC, C, Upper Abdomen Multiphases, and Whole Abdomen—was significantly higher than the national DRLs.Conclusion: The high $DLP$ values in many protocols are likely attributable to scan lengths (z-axis) exceeding clinical necessity. Therefore, there is an urgent need to review and implement dose optimization protocols, particularly by defining scan limits appropriate to clinical indications, to reduce patient radiation dose in accordance with national standards and the ALARA principle.