Enhanced radiation dose and DNA damage associated with iodinated contrast media in diagnostic X-ray imaging

Abstract

A review was undertaken of studies reporting increased DNA damage in circulating blood cells and increased organ doses, for X-ray exposures enhanced by iodinated contrast media (ICM), compared to unenhanced imaging. This effect may be due to ICM molecules acting as a source of secondary radiation (Auger/photoelectrons, fluorescence X-rays) following absorption of primary X-ray photons. It is unclear if the reported increase in DNA damage to blood cells necessarily implies an increased risk of developing cancer. Upon ICM-enhancement, the attenuation properties of blood differ substantially from surrounding tissues. Increased energy deposition is likely to occur within very close proximity to ICM molecules (within a few tens of micrometres). Consequently, in many situations, damage and dose enhancement may be restricted to the blood and vessel wall only. Increased cancer risks may be possible, in cases where ICM molecules are given sufficient time to reach the capillary network and interstitial fluid at the time of exposure. In all situations, the extrapolation of blood cell damage to other tissues requires caution where contrast media are involved. Future research is needed to determine the impact of ICM on dose to cells outside the blood itself and vessel walls, and to determine the concentration of ICM in blood vessels and interstitial fluid at the time of exposure.

DNA Damage in Blood Leukocytes of Prostate Cancer Patients Undergoing PET/CT Examinations with [68Ga]Ga-PSMA I&T

“…Many further studies used the γ-H2AX assay both ex vivo and in vivo for investigation of DNA damage in blood lymphocytes induced during CT examinations and, in particular, to investigate the effect of iodinated contrast agents [23,[29][30][31][32][33][34][35][36]. In agreement with the results of our ex vivo study, the majority of these studies report an increase of DNA damage in the contrast media-enhanced samples.…”

The impact of iodinated contrast media on intravascular and extravascular absorbed doses in X-ray imaging: A microdosimetric analysis

“…Clinical ρiI is likely to be in the range 0-10 mg/ml [9,10], though potentially up to 50 mg/ml for direct transcatheter injections [21]. A second issue is the potential compensatory increase in x-ray output by automatic exposure control (AEC) devices following contrast enhancement [5,11]. There is mixed evidence of a difference in CTDI or DLP for CT scans [23,24,36], though based on limited sample sizes.…”

“…In addition to well-known chemo/osmotoxic side effects, including allergic reactions and kidney damage [2], concerns have also been raised that contrast media may increase cancer risks from x-ray exposures [3,4]. Recently, we reviewed around four decades-worth of research investigating the radiation doses and associated DNA damage for ICM-enhanced, versus unenhanced x-ray exposures [5]. Increased DNA damage is likely to be a dosimetric effect, due to ICM molecules acting as a source of secondary radiation, i.e.…”

Three-Dimensional Rotational Angiography during Catheterization of Congenital Heart Disease – A ten Years’ experience at a single center

“…These findings are comparable to those in the reviewed literature. Besides the risk of adverse reactions to iodine carries, the biological effect of radiation is rising with a higher amount of contrast 28 . The great advantage of 3DRA is the fact that one single injection is sufficient to detect any lesion that may be undiagnosed with a conventional biplane angiography 3 .…”