Blessed Kondowe1*, Clement Dominic Chaphuka2, Patrick Manda1, Brave Kadoko Nyirenda1, Sope Msuku1, Master R O Chisale3, Zhe Liu4, Jin Shang4
- Mzuzu Central Hospital, Radiology Department, P/Bag 209, Mzuzu, Malawi
- Kamuzu Central Hospital, National Cancer Center, P.O Box 149, Lilongwe, Malawi
- Mzuzu University, Faculty of Science Technology and Innovations, Biological Science Department, Private Bag 201, Luwinga, Mzuzu 2, Malawi
- The First Affiliated Hospital of Xi’an Jiaotong University, Department of Medical Imaging, Xi’an, PR China
- Correspondence: Blessed Kondowe; E-mail: blessed.kondowe@yahoo.com
Abstract
Background
Diagnostic reference level (DRL) is an important tool used to identify abnormally high radiation doses, aid dose audits, and trigger investigations in diagnostic radiological imaging. This study aimed to develop local DRLs for the adult head, chest, and abdomen computed tomography (CT) examinations without contrast material at Mzuzu Central Hospital (MCH).
Methodology
This retrospective study was conducted at MCH radiology department using a NeuViz 16-slice Essence CT scanner from September 2023 to March 2024. The consecutive sampling method was used to extract data from patients’ head, chest, and abdominal images from advanced visualization workspace (AVW) and Picture Archiving and Communication Systems (PACS) using a checklist. All images were anonymized, and the data was kept in password-locked folders. Data was exported into SPSS version 26.0 software for analysis. Continuous variables were expressed as means and medians. Categorical variables were presented in form of tables as frequencies. The local DRLs were obtained by calculating the median radiation dose values by anatomical region.
Results
Out of 802 patients enrolled in this study, 361 (45%) had head CT examinations, 187 (23%) had chest CT examinations, and 254 (32%) had abdomen CT examinations without contrast. Local DRLs obtained by calculating the median of volume CT dose index (CTDIvol) and dose length product (DLP) for the head, chest, and abdomen CT examinations were 31 mGy, 5 mGy, 7 mGy, and 699 mGy.cm, 227 mGy.cm, and 331 mGy.cm, respectively.
Conclusion
Local DRLs for the head, chest, and abdomen have been developed for a NeuViz 16 Essence multi-detector CT scanner at MCH. The CTDIvol and DLP median values were lower or comparable to other single-facility, regional, and international values. This study should serve as a baseline for developing national adult CT DRLs for Malawi.
Keywords: Computed Tomography, Diagnostic Reference Levels, Volume-weighted Computed Tomography Dose Index, Dose Length Product, Radiation dose