Dosimetry during diagnostic cerebral DSA: implications for angiographic systems

Radiation doses delivered to skin, lens, and thyroid during diagnostic cerebral digital and conventional arteriographies are evaluated and compared. Some recommendations for the configuration of DSA (digital subtraction angiography) units are proposed. From this clinical study, it appears that for frontal projections, the X-ray tube must be under the patient to reduce the radiation dose to the lens. Digital angiography induces less irradiation than the conventional procedure when the same number of exposures are used. It is suggested that DSA units should allow for a change in the frame rate during an acquisition to decrease the number of exposures and consequently radiation doses.<>