Patient radiation doses in an angiography suite at a tertiary hospital in Pretoria

The rising demand for interventional radiology procedures (IRPs) performed under fluoroscopic guidance increases the risk of harmful radiation effects for patients and staff. Radiation dose optimisation using diagnostic reference levels (DRLs) is necessary to keep radiation 'as low as reasonably achievable (ALARA)'. Establishment of DRLs is required for radiation imaging centres; however, only a few have published them in South Africa. This study aimed to establish local diagnostic reference levels (LDRLs) for IRPs and compare them with DRLs of local and international imaging centres.

A retrospective descriptive study was conducted at a single imaging centre. The IRPs performed on adults between 01 January 2023 and 31 December 2023 were considered. Ethical clearance was obtained before data collection. Data on fluoroscopy time (FT) and kerma air product (KAP) were obtained from a procedure register book. The third quartile (75th percentile) of the dataset for KAP and FT of every IRP indicated the LDRLs.

A total of 375 IRPs were analysed. The most frequently performed IRP was cerebral interventions (21%, n = 80). Aortic interventions recorded the highest dose LDRL (KAP = 252.5 Gy/cm²), followed by cerebral interventions (KAP = 211.3 Gy/cm²). Cerebral interventions recorded the longest FT (56.8 min), followed by aortic interventions (36.2 min), both of which exceeded the local centres' DRL ranges. Permanent catheterisation (KAP = 10.7 Gy/cm²) also exceeded the international DRL range.

Established LDRLs for IRPs were mostly within local and international DRL ranges.

The study contributed to the establishment of local, national and regional DRLs, which assisted imaging centres in optimising radiation doses for IRPs.