Purpose: Gadolinium and iodinated contrast agents are known to enter subarachnoidal space (SAS) in various pathologies and mimicking hemorrhage and/or leading to neurotoxicity. In this study, effect of carotid artery stenting (CAS) procedures conducted during and after MRI examinations with gadolinium on contrast agent diffusion in SAS.
Materials and methods: This study included 10 patients (seven males and three females) who received time-resolved imaging of contrast kinetics (TRICKS) MRA examinations and then CAS procedures because of carotid stenosis during the period from May 2009 to May 2011. Age of the patients varied from 52 to 84 (mean 73.40±8.75). Diffusion MRI examination was practiced along with fluid-attenuated inversion recovery (FLAIR) sequence in eight patients before stent placement and in all patients after the stent placement.
Results: In control FLAIR sequence conducted 1.5 to 3 hours interval after CAS, contrast agent diffusion in subarachnoid space was observed in four of the patients. There were significant differences between patients who had contrast matter diffusion into SAS and who did not in terms of duration between TRICKS MRA and CAS procedure as well as the presence of ischemic lesion due to the procedure (p=0.011, p=0.005, respectively).
Conclusion: Secondary complications that develop within 24 hours after CAS procedures conducted in contrast-enhanced MRI examinations using gadolinium chelates and iodinated contrast agent used in these procedures may cause gadolinium diffusion in SAS. We conclude that the iodine containing contrasted examinations and procedures can be safer when conducted at least two days after gadolinium containing MRI examinations.
carotid artery stenting; gadolinium; iodinated contrast agents; magnetic resonance angiography; subarachnoidal space