Protective Effect of Oral Steroid Premedication: Adverse Reactions to Nonionic Iodine Contrast Media for Computed Tomography

This study aimed to investigate the protective effect of oral steroid premedication in terms of adverse reactions to non-ionic contrast media. We investigated the incidence of adverse reactions among patients who underwent contrast-enhanced computed tomography. Patients in the premedication group took 30 mg of prednisolone orally the night before and on the morning of the scheduled computed tomography. Sixty-five patients received the same contrast media. Among them, 56 took prednisolone orally prior to the procedure (premedication without change of contrast media group) and nine without premedication (no premedication and no change of contrast media group). In total, 379 patients received different contrast media. Among them, 340 took prednisolone orally (premedication with change of contrast media group), while 39 did not take the premedication (no premedication with change of contrast media group). The adverse reaction rates in the premedication with change of contrast media and no premedication with change of contrast media groups were 1.8% (6/340 cases) and 2.6% (1/39 cases) (P = 0.54), respectively. The incidence of adverse reaction after the administration of non-ionic iodinated contrast media did not differ significantly based on whether an oral steroid was administered prior to compute tomography. Our evaluation is limited due to the small sample size of the contrast media-changed group. However, even if premedication with steroids is effective, it may only result in an adverse reaction reduction rate of ≤3%.

Ultrasound-guided carotid angioplasty and stenting in a patient with iodinated contrast allergy:A case report

BACKGROUND Ischemic stroke is an entity with high incidence,morbidity,and mortality rates.Carotid artery stenosis is an important and independent risk factor for ischemic stroke.The three current approaches for treating carotid artery stenosis are drug treatment,carotid endarterectomy(CEA),carotid angioplasty and stenting(CAS).The approach is chosen based on the degree of stenosis.CEA or CAS could have been chosen for the current patient,who had severe carotid stenosis and an iodinated contrast allergy.After thoroughly communicating with the patient,the patient chose CAS for treatment.Therefore,we performed ultrasound-guided CAS to avoid the use of iodinated contrast.CASE SUMMARY The main symptoms of the patient were numbness and weakness of the left limb.Computed tomography angiography of the head and neck at another hospital indicated multiple sites of stenosis in the arteries of the head and neck.The patient requested CAS for treatment but was allergic to iodinated contrast media.Thus,routine digital subtraction angiography(DSA)with iodinated contrast could not be used for the procedure.The diagnosis of this patient was as follows:(1)Right parietal lobe cerebral infarction;(2)multiple sites of stenosis in the arteries of the head and neck(severe stenosis of the right internal carotid artery,severe stenosis of the right subclavian artery);(3)right subclavian steal syndrome;and(4)hypertension(stage 3,high risk).The interventions included routine treatment for cerebral infarction,oral administration of clopidogrel(75 mg qd)and aspirin(100 mg qd),ultrasound-guided CAS,and postoperative follow-up.Postoperative color Doppler ultrasound and cerebrovascular magnetic resonance angiography of the carotid artery showed good vascular recovery,and the postoperative follow-up indicated a good prognosis.CONCLUSION This case study suggests that ultrasound-guided endovascular treatment is a potential option for patients with contraindications to the iodinated contrast agents used in DSA-guided surgery,although excellent surgical operating skills are needed.

Predictive Study of Velocimetry in the Coronary Artery after Iodinated Contrast Agent Injection

This study aims to determine the retention time of iodinated contrast agents (ICA) in the coronary artery. The mechanical aspect of ICA displacement was studied in order to better understand the effect of these products on the inner wall of the artery of patients with coronary artery stenosis, undergoing repeated imaging examinations with iodinated contrast agents. ICA flow, ICA and blood flow in the artery were modelled. The fluid was regarded to be viscous, incompressible and Newtonian. Blood flow was presumed to be unidirectional, laminar and unstationary. Iodine flow velocity and retention time were calculated using the Runge-Kutta 4th order method programmed in C++ and MatLab R2013a language. The results showed that for coronary artery CT-scans, ICA retention time is 1 minute 40 seconds and for coronary arteriography it is between 2.41 and 3.61 seconds. The values calculated were compared to theoretical values and to clinical observations. The results enabled us to validate our model.

Right time to detect urine iodine during papillary thyroid carcinoma diagnosis and treatment:A case report

BACKGROUND This is the first documentation of a spontaneous and nonspecific chemical reaction of an iodinated contrast media with ammonium persulfate used in As3+-Ce4+catalytic spectrophotometry for urine iodine concentration(UIC)detection.CASE SUMMARY We herein report an incidental case who had a dual source computed tomography examination for papillary thyroid carcinoma diagnosis.Serial spot urine specimens were collected during her hospitalization and were measured by As3+-Ce4+catalytic spectrophotometry on a Beckman Coulter AU5800.The reacted solutions were“brownish”,and the results showed extremely high iodine concentrations despite serial dilutions.The patient claimed no dietary habit of iodized salt or iodine-containing medical history,which strongly pointed to iodinated contrast media(ICM)via intravenous injection.Even with 0.01%ICM,its interruption is still profound on the desired urine iodine reaction with ammonium persulfate,leading to inaccurate UIC and possibly inappropriate treatment.CONCLUSION The following laboratory suggestions should be considered:(1)As3+-Ce4+catalytic spectrophotometry is only suitable for UIC measurement after confirmed ICM renal clearance;(2)A mass spectrometry-based method can be applied as an alternative during the ICM clearance period;and(3)The UIC baseline can be confirmed after ICM injection by consecutive detection for at least 2 mo.

Thyroid Dysfunction in Children Exposed to Iodinated Contrast Media:A Meta-Analysis and Systematic Review

Iodinated contrast media(ICM)has the potential to cause thyroid dysfunction in some patients.However,it is unclear whether this relationship exists in children.We conducted a systematic review and meta-analysis aim to obtain a general overview of the relationship between ICM exposure and the risk of thyroid dysfunction in children.Methods:Computer search of Web of Science,EMbase,PubMed,Cochrane Library,collection of relevant literature on ICM and thyroid dysfunction in children,the search period was from the establishment of the database to July 2021.Meta-analysis was performed using Stata 14.0 software.Results:A total of 8 literatures with 3497 children.The incidence of hypothyroidism in children with ICM exposure was 0.05(95%CI:0.05,0.12),P<0.0001.Subgroup analysis showed that the incidence of hypothyroidism in ICM exposed children in the European region was 0.21(95%CI:0.13,0.30),P<0.0001,a statistically significant difference.Conclusion:The current evidence shows that children exposed to ICM are at risk for hypothyroidism,with a higher risk in neonates,especially children with congenital heart disease.

Manifesting viscosity changes in lipid droplets during iodined CT contrast media treatment by the real-time and in situ fluorescence imaging

Computed tomography(CT) is one of the most commonly used non-invasive clinical imaging modalities to predict, diagnose and treat the disease. Iodinated contrast media(ICM) is a form of intravenous radiocontrast agent containing iodine, which enhances the visibility of hollow tissue structures in medical CT imaging. ICM may cause allergic reactions, contrast-induced nephropathy, hyperthyroidism and possibly metformin accumulation. It is significant to find out the risk factors, pathogenesis, diagnosis, prevention, and treatment of adverse reactions caused by ICM. Revealing the changes of the lipid droplets(LDs)viscosity in pathophysiological processes such as cancer and iodined contrast media induced adverse reaction is not only important for monitoring the occurrence and development of some pathophysiological processes but also vital for the deep insight of the biological effects of LDs in these pathophysiological processes. A lipid droplets targeted fluorescent probe DN-1 was devised to sense cellular viscosity alteration with high selectivity and sensitivity, which was applied to distinguish cancer cells and normal cells and reveal viscosity changes during iodined CT contrast media treatment.

Long-term effect of a large dose of iodinated contrast in patients with mild thyroid dysfunction:a prospective cohort study

Background:More than 75 million procedures with intravascular iodine-based contrast media(ICM)are performed worldwide every year,and some patients undergoing these procedures do not have normal thyroid function.The long-term effects of ICM in patients with mild thyroid dysfunction(TD)are unclear.Methods:This prospective cohort study was conducted in China.Patients with stable angina pectoris with total triiodothyronine(TT3)reduction,normal thyroid-stimulating hormone,and reverse triiodothyronine(rT3)were enrolled and divided into high-dose(≥100 mL ICM)and low-dose groups(<100 mL ICM).We dynamically investigated the trends in thyroid function,rT3,and thyroid antibodies one year after ICM exposure.Results:A total of 154 patients completed 6 months of follow-up and 149 completed 1 year of follow-up.Thyroglobulin antibody(TGAB)levels were elevated in 41(26.6%)patients before ICM exposure,11(7.1%)of whom also had elevated thyroid peroxidase antibody levels.Transient subclinical TD occurred 6 months after ICM exposure;75.5%(34/45)of post-operative TD occurred in the high-dose group.One patient developed severe hypothyroidism with myxedema,requiring drug intervention 1 year after ICM exposure.The level of rT3 showed no statistically significant changes during post-operative follow-up(P=0.848).The TGAB level decreased at 6th month(P<0.001),but increased at 1 year after ICM exposure(P=0.002).Conclusions:Patients with T3 reduction are at a risk of transient subclinical TD and hypothyroidism after a single large dose of ICM.Follow-up of this population at 9-12 months after ICM exposure is warranted.

Degradation of iodinated X-ray contrast media by advanced oxidation processes:A literature review with a focus on degradation pathways

Available online Iodinated X-ray contrast media (ICMs) are clinical drugs used to enhance the imaging effect.Triiodobenzene ring structures of ICMs lead to its extremely high chemical stability,biological inertness,which makes it difficult to be completely removed by traditional water treatment processes.Hence,considerable concentration of ICMs can be frequently detected in aquatic environment.Relying on the strong oxidation capacity of HO·or SO_(4)^(·-),various advanced oxidation processes (AOPs) have demonstrated substantial removal efficiency for ICMs.It is evident that ICMs can be decomposed mainly through(1) deiodination,(2) dehydration,(3) decarboxylation,(4) H-abstraction,(5) hydroxyl addition,(6) hydroxyl substitution,(7) oxidation of alcohol groups,(8) cleavage of amide bond,and (9) amino oxidation.However,during the ICMs removal process,the C-I bonds of ICMs molecules are broken,giving rise to the formation of cytotoxic iodination disinfection by-products (I-DBPs) that are potentially more harmful to the ecosystem and human health than their parent compounds.To better understand the technology gaps,this review elaborates the major AOPs which are effective for ICMs removal and emphasizes on the main degradation routes of ICMs in different oxidation system.Some prevailing concerns and challenges are discussed for optimizing the ICMs treatment process.

The impact of iodinated X-ray contrast agents on formation and toxicity of disinfection by-products in drinking water

The presence of iodinated X-ray contrast media（ICM） in source waters is of high concern to public health because of their potential to generate highly toxic disinfection by-products（DBPs）. The objective of this study was to determine the impact of ICM in source waters and the type of disinfectant on the overall toxicity of DBP mixtures and to determine which ICM and reaction conditions give rise to toxic by-products. Source waters collected from Akron,OH were treated with five different ICMs, including iopamidol, iopromide, iohexol,diatrizoate and iomeprol, with or without chlorine or chloramine disinfection. The reaction product mixtures were concentrated with XAD resins and the mammalian cell cytotoxicity and genotoxicity of the reaction mixture concentrates was measured. Water containing iopamidol generated an enhanced level of mammalian cell cytotoxicity and genotoxicity after disinfection. While chlorine disinfection with iopamidol resulted in the highest cytotoxicity overall, the relative iopamidol-mediated increase in toxicity was greater when chloramine was used as the disinfectant compared with chlorine. Four other ICMs（iopromide, iohexol, diatrizoate, and iomeprol） expressed some cytotoxicity over the control without any disinfection, and induced higher cytotoxicity when chlorinated. Only iohexol enhanced genotoxicity compared to the chlorinated source water.