Establishment of typical values in computed tomography to support the optimization of protection in clinical practice

Typical values, as defined by the International Commission on Radiological Protection, support the optimization of protection in Computed Tomography (CT). They provide comparisons when new technologies are introduced, as well as for assessing the impact of factors such as the number of phases per examination, image-quality adjustments, and clinical-indication-based prescribing. This study assessed CT dose levels in a radiology department using a two-phase approach. Part I retrospectively assessed volume computed tomography dose index, dose length product, and size specific dose estimate values (2021-2022) across clinical indications and compared them with international Diagnostic Reference Levels. Protocol standardization, staff training, and optimization measures were implemented. Part II prospectively evaluated outcomes in 2024. Results showed that median dose values frequently exceeded international benchmarks and revealed variability in local practice. After optimization, most examinations demonstrated dose reductions of up to 61%, although some procedures remained ~20% above references. These findings highlight how multidisciplinary collaboration and staff education can strengthen radiation-protection culture and support clinically aligned imaging practice.