Measurement of Computed Tomography Dose Indices at a Clinic in Abidjan, Côte d’Ivoire
Agba Dabo Salif Ignace *
Laboratoire de Physique Fondamentale et Appliquee (LPFA), Unite de Formation et de Recherche des Sciences Fondamentales et Appliquees (UFR SFA), Universite Nangui Abrogoua (UNA), 02 BP 801 Abidjan 02, Coote d’Ivoire and Equipe de Physique Nucleaire et Radioprotection (EPNR), Laboratoire des Sciences de la Matiere, de l’Environnement et de l’Energie Solaire (LASMES), Unite de Formation et de Recherche des Sciences des Structures de la Matiere et de Technologie (UFR SSMT), Universite Felix Houphouet Boigny (UFHB), 22 BP 582 Abidjan 22, Cote d’Ivoire.
Kouadio Landji Dibert
Equipe de Physique Nucleaire et Radioprotection (EPNR), Laboratoire des Sciences de la Matiere, de l’Environnement et de l’Energie Solaire (LASMES), Unite de Formation et de Recherche des Sciences des Structures de la Matiere et de Technologie (UFR SSMT), Universite Felix Houphouet Boigny (UFHB), 22 BP 582 Abidjan 22, Cote d’Ivoire.
Agbo Djoman Djama Alfred
Equipe de Physique Nucleaire et Radioprotection (EPNR), Laboratoire des Sciences de la Matiere, de l’Environnement et de l’Energie Solaire (LASMES), Unite de Formation et de Recherche des Sciences des Structures de la Matiere et de Technologie (UFR SSMT), Universite Felix Houphouet Boigny (UFHB), 22 BP 582 Abidjan 22, Cote d’Ivoire.
Koua Aka Antonin
Equipe de Physique Nucleaire et Radioprotection (EPNR), Laboratoire des Sciences de la Matiere, de l’Environnement et de l’Energie Solaire (LASMES), Unite de Formation et de Recherche des Sciences des Structures de la Matiere et de Technologie (UFR SSMT), Universite Felix Houphouet Boigny (UFHB), 22 BP 582 Abidjan 22, Cote d’Ivoire.
*Author to whom correspondence should be addressed.
Abstract
Background: Computed tomography (CT) is widely used for diagnostic imaging because of its ability to provide detailed anatomical information. However, CT examinations involve exposure to ionizing radiation, making dose optimization and routine quality control essential for patient safety. In Côte d’Ivoire, the increasing use of CT scanners highlights the need to assess the accuracy of displayed radiation-dose indices and to support the implementation of appropriate quality-control procedures under local clinical conditions.
Aims: This work contributes to the implementation of quality control for computed tomography (CT) scanners used in Côte d’Ivoire.
Place and Duration of Study: The study was conducted at RIMCA clinic in Koumassy, Abidjan, over a period of two weeks.
Methodology: Using a 16-slice multi-detector-row CT scanner, an ionization chamber, a DOSE-1 electrometer, and a PMMA phantom, the computed tomography dose indices for a 100 mm ionization chamber (CTDI100) were measured for head and body phantom exposures. The weighted CT dose indices (CTDIw), as well as the differences between the measured volume CT dose indices (CTDIvol) and dose-length products (DLP) and their respective displayed values, were then calculated.
Results: For the head phantom exposure, the percentage differences in CTDIvol and DLP were 0.02% and 10.24% at 80 kVp and 6.48% and 3.41% at 120 kVp, respectively. For the body phantom exposure, the corresponding differences were 0.46% and 9.15% at 100 kVp and 3.14% and 13.68% at 120 kVp.
Conclusion: The percentage differences obtained were less than 20%, and most were below 10%. International organizations such as the International Electrotechnical Commission (IEC) recommend a percentage difference of less than 20%, and ideally less than 10%. Therefore, the results obtained complied with this recommendation. Thus, the CT scanner employed was of high quality in terms of CTDI accuracy.
Keywords: CT scanner, ionization chamber, electrometer, PMMA phantom, CTDIvol, DLP accuracies