Cardiac CT and radiation dose: what is the risk in practice for the patient?

Introduction

A recent study published in JAMA estimated the long-term radiation-induced risk associated with cardiac CT, according to the linear no-threshold risk theory. In this model, the risk is proportional to the dose received with no lower risk-free threshold.

The maximal risk of long-term radiation-induced cancer was estimated to be 1 in 143 (0.70%) for a 20-year-old woman, when a 64-slice CT scanner was used without dose optimisation.

Thus, this paper raises the question of the risk-benefit ratio associated with cardiac CT.