Adverse events with universal use of iodixanol for CT: comparison with iohexol

OBJECTIVE: To evaluate the incidence of adverse events with the universal use of iodixanol for computed tomography (CT) and compare it with periods when iohexol was used exclusively. METHODS: Iodixanol was used for CT in 15,142 consecutive patients and compared with 22,044 patients who received iohexol. RESULTS: Adverse events were observed in 116 patients (0.77%) who received iodixanol and in 54 patients (0.25%) who received iohexol (P < 0.001). Immediate and delayed adverse events were seen in 76 and 40 patients (0.50% and 0.26%, respectively) who received iodixanol and in 52 and 2 patients (0.24% and 0.01%, respectively) who received iohexol, respectively (immediate, P = 0.002; delayed, P < 0.001). Adverse events with iodixanol and iohexol were as follows: mild, 89% and 98%; moderate, 10% and 2%; and severe, 1% and 0%, respectively. CONCLUSIONS: Adverse events occurred in less than 1% of patients receiving either contrast agent. However, the incidence of immediate and delayed adverse events was significantly higher with iodixanol than iohexol.     

A double-blind, prospective, randomized, multicenter group comparison study of iopromide 240 vs iohexol 240 in myelography

The aim of this study was to evaluate the safety and efficacy of iopromide 240 mgI/ml in comparison with iohexol 240 mgI/ml in myelography. A total of 421 patients in seven centers and four countries received an average of 11.9 ml of either iopromide 240 (278 patients) or iohexol 240 (143 patients) for X-ray and/or CT myelography in a randomized (2:1), prospective, double-blind study. All patients were followed up 3–4 h after the procedure, and 327 patients remained hospitalized for 24 h. In 82 patients an EEG was recorded prior to as well as 3–4 h and 24 h after myelography. Physical examinations, including measurement of vital signs, were performed in all patients at these time points. The results were subject to statistical analysis with the primary variable being the incidence of adverse events. Both contrast media (CM) were equally effective in terms of opacification. The rating for opacity was “good” or “excellent” in 88 % for both CM. Four patients (iopromide group: n = 3; iohexol group: n = 1) had transient EEG changes but did not show clinical symptomatology. The overall rate of patients experiencing any adverse event (AE) was 16.9 % for iopromide 240 and 14.0 % for iohexol 240. Equivalence testing was inconclusive; however, the results indicated equivalence. The rate for AEs considered as study-drug related was slightly lower with iopromide 240 than with iohexol 240 (7.2 vs 7.7 %, respectively). Neither unknown nor unexpected AEs known for myelographic X-ray CM nor serious adverse events were observed. Iopromide 240 and iohexol 240 are equally safe and effective and can be recommended for myelography. Received: 19 August 1998; Revision received: 26 November 1998; Accepted: 4 February 1999     

Safety of Conscious Sedation In Interventional Radiology

Purpose: To identify rates of adverse events associated with the use of conscious sedation in interventional radiology. Methods: In a 5-month period, prospective data were collected on patients undergoing conscious sedation for interventional radiology procedures (n = 594). Adverse events were categorized as respiratory, sedative, or major adverse events. Respiratory adverse events were those that required oral airway placement, ambu bag, or jaw thrust. Sedation adverse events were unresponsiveness, oxygen saturation less than 90%, use of flumazenil/naloxone, or agitation. Major adverse events were hypotension, intubation, CPR, or cardiac arrest. The frequency of adverse events for the five most common radiology procedures were determined. Results: The five most common procedures (total n = 541) were biliary tube placement/exchange (n = 182), tunneled catheter placement (n = 135), diagnostic arteriography (n = 125), vascular interventions (n = 52), and other catheter insertions (n = 46). Rates for respiratory, sedation, and major adverse events were 4.7%, 4.2%, and 2.0%, respectively. The most frequent major adverse event was hypotension (2.0%). Biliary procedures had the highest rate of total adverse events (p < .05) and respiratory adverse events (p < .05). Conclusion: The frequency of adverse events is low with the use of conscious sedation during interventional procedures. The highest rates occurred during biliary interventions.     

Late reactions to a radiologic contrast media (Iopamidol-Bracco). Prospective study

PURPOSE: This prospective, non-randomized study was aimed at evaluating the incidence of Delayed Adverse Drug Reactions (DADRs) to iodinated contrast agents and to evaluate possible risk factors to the development of these reactions. DADRs are those reactions occurring one to 48 hours after contrast medium administration. Their symptoms and frequency are not well defined, but the majority of DADRs are mild in intensity and resolve spontaneously without sequelae. In the literature, DADRs are reported to occur in 1 to 15% of patients undergoing contrast-enhanced examinations. MATERIAL AND METHODS: This prospective, non-randomized trial was carried out on 403 patients undergoing either dynamic CT or urography with iopamidol-300 (Iopamiro-300, Bracco SpA). Before the examination, data were collected regarding patients' anagraphical details, presence of risk factors, allergy, previous exposure and previous adverse reactions to iodinated contrast agent. After the examination, any adverse events occurring between 30 minutes and 48 hours post-dose were recorded, specifying time of onset and duration of symptoms. Studied variables were type of DADRs and risk factors to their development (sex, age, underlying disease, allergy, previous exposure to contrast agent, type of diagnostic examination). Two hundred and sixty-two patients were male (65%), and 141 were female (35%). Mean age was 61 years (+/- 11.8); 192 patients (48%) had underlying disease, and 115 (28%) were allergic. About half of the patients had previously undergone another contrast-enhanced examination. Two hundred and seventy-one patients underwent dynamic CT and 132 urography. RESULTS: A total of 50 patients (12.4%) reported DADRs. Factors associated with a significantly higher incidence of DADRs were found to be allergy (p = 0.001), previous exposure to contrast agent (p = 0.001), female sex (p = 0.001), underlying disease (p = 0.030). The most frequently reported DADRs were nausea and vomiting, drowsiness, rash, itching and headache. All reported reactions were mild and resolved spontaneously without sequelae. DISCUSSION AND CONCLUSIONS: In our experience, though limited and not on large numbers, DADRs to nonionic low osmolality contrast agents such as iopamidol have been few, mild, and not clinically significant. Although there are no absolute contraindications to the use of iodinated contrast agent, the risk/benefit ratio should always be evaluated, especially in patients with allergy, in those with severe renal, hepatic or cardiac insufficiency, and in diabetics.     

Safety of iobitridol in the general population and at-risk patients

The purpose of this study was to review the rate of adverse events after contrast medium administration in the general population and at-risk patients (renal impairment, heart failure (NYHA III or IV), hypotension or hypertension, coronary artery disease, previous reaction to contrast media, asthma and/or allergies, dehydration, diabetes mellitus, poor general condition) under daily practice conditions in a post-marketing surveillance study. Two hundred and ten radiologists conducted various X-ray examinations in 52,057 patients. To document the safety of iobitridol in routine use, all patients undergoing X-ray examinations were included. Exclusion criteria were contraindications listed in the locally approved summary of product characteristics. The adverse event rate was 0.96% (at-risk patients 1.39%); the rate of serious adverse events 0.044% in all patients (at-risk patients 0.057%). Adverse events occurred more often in women than in men (P<0.001). In patients who had previously reacted to a contrast medium, adverse events were reported in 3.43% with mild to moderate symptoms. In 47.76% of these patients, a premedication was administered. There was no difference in the frequency of adverse events and serious adverse events whether premedicated or not (P=0.311 and P=0.295, respectively). Iobitridol was well-tolerated in 99.04% of cases (at-risk patients 98.61%).     

Clinical safety assessment of iotrolan 280 in European clinical studies

Iotrolan (280 mg iodine/ml) a new non ionic, isotonic dimeric, contrast agent, was evaluated in multicenter clinical stidues conducted in Europe between March 1987 and September 1992. The studies compared the efficacy and safety of the agent with the non-ionic monomeric contrast agents available at the time. Iotrolan was given intravenously to patients undergoing urography, head and body computed tomography phlebography and digital subtraction angiography. The agent was also studied after intra-arterial injections in cerebral, visceral and peripheral angiographic procedures as well as digital subtraction angiography. Data from 32 prospective double blind, randomized, controlled clinical studies, were evaluated. A total of 1203 patients received either iopromide, iohexol or iopamidol (all in concentration of 300 mg iodine/ml), and a further 1207 patients received iortrolan. As there were no sognificant differences (P = 0.0853) in adverse events between the comparative agents, their adverse event data were pooled for evaluation with data from patients receiving iotrolan. Adverse experiences were recorded in two categories — local tolerance (heat and pain) and general tolerance (generalized heat and adverse clinical events). After intra-arterial injection iotrolan had a significantly lower incidence of local heat sensation (P = 0.0001) and a significantly lower incidence of local pain (P = 0.0001) compared with comparator agents. Also, after intravenous injection iotrolan had a significantly lower incidence of local heat (P = 0.0038). In the overall evaluation of general tolerance for all indications, iotrolan was shown to produce significantly less generalized heat (P = 0.0012) and a lower incidence of adverse events (P = 0.061) compared with the reference agents.     

Iodixanol,a new non-ionic,dimeric contrast medium in cardioangiography: a double-masked,parallel comparison with iopromide

Iodixanol (320 mg I/ml) was compared with iopromide (370 mg I/ml) in a double-masked, parallel group, randomised trial of 120 patients undergoing cardioangiography in order to evaluate and compare safety, tolerability and radiographic efficacy. The overall diagnostic information and radiographic density were mainly optimal and no differences between the contrast media were detected. No serious adverse events were reported in either group, and there were no clinically relevant changes in blood chemistry. A statistically significant difference was found between the groups regarding discomfort during injection of contrast medium, the intensity of warmth being less for iodixanol (P = 0.003). Blood pressures and heart rate remained practically unchaged during coronary arteriography in both groups. During left ventriculography, the peak systolic pressure decreased after injection of iopromide (mean change ±SD: – 7.9 ± 11.1 mm Hg, P < 0.001), while there was no significant change after injection of iodixanol (mean change± SD: 0.9 ± 8.3 mm Hg). The results indicate that both contrast agents are effective, safe and well tolerated in cardioangiography, but administration of iodixanol results in a less intense sensation of warmth and a slightly better haemodynamic profile than does administration of iopromide. Correspondence to: H. Manninen     

Acute adverse reactions to iopromide vs iomeprol: a retrospective analysis of spontaneous reporting from a radiology department

Objective:

To compare the safety of iopromide and iomeprol use in a hospital that switched from the former to the latter and found an apparent increase in the number (and a different profile) of adverse reactions reported for iomeprol, putting the safety of its use into question.

Methods:

This was a retrospective study of cases of acute reactions to iopromide and iomeprol reported in two successive time periods. Data from examinations using iopromide (62 539 CT scans and 10 348 urography scans) and iomeprol (34 308 CT scans and 2846 urography scans) were obtained from the computer system of the hospital.

Results:

For each period, 154 cases of reactions were reported for iopromide and 86 for iomeprol, being severe in 10 (6.5%) patients for iopromide vs 17 (19.8%) patients for iomeprol; a statistically significant difference of p < 0.003 was recorded. The most frequent adverse reactions (%/%) for iopromide/iomeprol were urticaria (29.1/17.2), pruritus (22.6/15.6), upper respiratory tract signs and symptoms (12.1/16.7), oedema (4.3/0), erythemas (3.4/5.0), nausea or vomiting (1.2/11.7) and chest pain (0/3.9) (p < 0.0001 for the global comparison). The distribution of the reactions (%/%) by System Organ Class for iopromide/iomeprol was skin (56.7/41.1), respiratory (19.2/26.7), vascular (6.8/2.2), general (5.3/7.2), gastrointestinal (4.6/15.0) and others (7.4/7.9) (p < 0.0002 for the global comparison).

Conclusion:

Adverse reactions were more severe for iomeprol. Skin and vascular reactions with no chest pain were more frequent for iopromide, whereas gastrointestinal reactions were more frequent for iomeprol.

Advances in knowledge:

Comparative studies of media contrast safety are scarce and summary information on product characteristics is insufficient. This study showed the differences in severity and profile of adverse reactions between iopromide and iomeprol.The generalization of the use of non-ionic contrast media (CM) in recent decades in many hospitals has improved the safety of patients who are to be examined using CM, with 0.2–0.7% of patients reporting slight or moderate adverse reactions^1–3 and 0.04% reporting reactions that endanger patients,³ and a mortality rate of 0.9 per 100 000 injections, according to a meta-analysis.⁴ Nevertheless, there are very few comparative studies of the efficacy and safety of CM, and the information about adverse reactions is similar in terms of the technical specifications of many of them.When a change occurs in the CM that is to be used in a hospital, which is frequently not a decision made by the radiology department, the new contrast can change the profile or incidence of adverse effects, which in turn can cause uncertainty among patients and radiologists, who had until then been used to a specific incidence and/or severity.Our hospital recently began using the contrast iomeprol⁵ in indications where iopromide had been used previously, because of financial reasons. Coinciding with this switch, there was an apparent increase in the number and a different profile of adverse effects reported for iomeprol, putting the safety of its use into question. Moreover, the information available on the technical specifications of both contrasts does not provide data on the incidence or the severity of adverse effects for either of them.Therefore, a comparative analysis of the adverse effects observed for both contrasts was conducted to determine differences regarding the incidence, severity and the type of adverse effects between iopromide and iomeprol, using spontaneously reported data. The absence of a reporting bias was assumed, given that they were conducted in the same hospital and in consecutive periods of time.     

Dy-EOB-DTPA: tolerance and pharmacokinetics in healthy volunteers and preliminary liver imaging in patients

RATIONALE AND OBJECTIVES: To investigate the tolerance and pharmacokinetics of the new liver-specific x-ray contrast agent Dy-EOB-DTPA [(4S)-4-(4-ethoxybenzyl)-3,6,9-tris(carboxylatomethyl)-3,6,9-triazaundecanedioic acid, dysprosium (Dy) complex, disodium salt] in healthy volunteers and to obtain preliminary imaging data by abdominal spiral computed tomography (CT) in tumor patients with liver metastases. METHODS: A total of 40 healthy male volunteers received 10-minute intravenous infusions of 0.05, 0.1, 0.25, 0.375, or 0.5 mmol/kg Dy-EOB-DTPA (n = 6 per dose group) or placebo (n = 10). Blood, urine, and feces were sampled for Dy measurements by inductively coupled plasma atomic emission spectrometry (ICP-AES) and for the detection of possible metabolites by high-performance liquid chromatography analysis with ICP-AES detection. Safety parameters were determined before, during, and after the study. Two patients with suspected liver metastases first received 120 mL of iopromide (300 mg iodine/mL; approximately 0.6 mmol/kg) and, 24 or 72 hours later, Dy-EOB-DTPA at a dose of 0.25 mmol/kg. Computed tomography images were obtained 50 seconds after iopromide administration and before and 90 minutes after Dy-EOB-DTPA administration. RESULTS: Dysprosium-EOB-DTPA was well tolerated. At the higher doses (0.375 and 0.5 mmol/kg), there was a slight increase in side effect intensity. In general, nausea, headache, and paresthesia mainly were reported as mild to moderate adverse events. Laboratory parameters did not exceed the normal range. Electrocardiographic, vital sign, or hemodynamic parameters were not affected by contrast agent administration. The terminal half-life of elimination of Dy-EOB-DTPA was approximately 1.5 hours, total clearance was 2 to 3 mL x min(-1) x kg(-1), and the renal clearance was approximately 1.5 mL x min(-1) x kg(-1). There was a significant dose dependence for the following parameters: maximal concentration in blood, terminal half-life, mean residence time, total clearance, urinary excretion, and fecal excretion. The volume of distribution in the steady state and renal clearance were not dependent on dose. In the blood and urine, no metabolites of Dy-EOB-DTPA could be detected. In the tumor patients, CT scanning after Dy-EOB-DTPA injection increased the number of detected metastases from 27 (plain scan) to 40 (iopromide) and then to 41 (Dy-EOB-DTPA) in patient No. 1 and from 1 (plain scan and iopromide) to 3 (Dy-EOB-DTPA) in patient No. 2. CONCLUSIONS: Dysprosium-EOB-DTPA was shown to be a well-tolerated liver-specific contrast agent. Its pharmacokinetic profile is characterized by a terminal half-life of approximately 1.5 hours. There are indications of saturation of liver uptake at the highest dose level of 0.5 mmol/kg. In comparison with plain scans and scans performed after iodinated contrast agent administration, Dy-EOB-DTPA seems to increase the number of detectable liver lesions.     

Iomeprol: current and future profile of a radiocontrast agent

RATIONALE AND OBJECTIVES: To review the safety and efficacy profiles of iomeprol by examining the most indicative comparative clinical studies of iomeprol with widely used low-osmolar ionic or nonionic contrast agents, and to illustrate the recent development in iomeprol liposomal formulations for liver imaging and intravascular enhancement. METHODS: Randomized, double-blind, comparative studies were performed of iomeprol versus iopamidol, iopromide, ioxaglate, iopentol, iodixanol, ioversol, and iohexol. In all studies, safety controls included pre- and postadministration physical examinations, monitoring of vital signs, electrocardiography, clinical laboratory investigations, and 24- or 72-hour postadministration monitoring of patients for adverse events. Technically adequate images were rated for diagnostic efficacy by masked assessors. RESULTS: Iomeprol showed similar safety and diagnostic efficacy compared with the nonionic monomers iopamidol, iohexol, and ioversol, and no statistically significant differences were observed. No differences in diagnostic efficacy between iomeprol and iopromide were observed, but in one study on 1,200 patients, the incidence of adverse events and adverse reactions was significantly higher with iopromide than with iomeprol. Iomeprol caused significantly less heat/pain than iopentol in one study; it showed similar safety and tolerability to the nonionic dimer iodixanol, the two agents causing no or modest, superimposable pain and heat sensation at injection and showing similar renal tolerability after intra-arterial injection. A comparison of iomeprol versus ionic dimer ioxaglate in 2,000 patients undergoing percutaneous coronary interventions showed that the incidence of thrombus-related events was similar with the two agents, but ioxaglate caused a significantly higher incidence of allergy-like reactions. First results with iomeprol-containing liposomal formulations show that these agents may facilitate the CT assessment of intrahepatic malignancies and CT angiography procedures. CONCLUSIONS: The overall results of numerous randomized, double-blind, comparative clinical studies in a variety of indications show that the diagnostic efficacy of iomeprol solutions does not differ significantly from that of the low-osmolar contrast media available on the marketplace when similar iodine strengths are used, although iomeprol may have better tolerability and safety than the ionic dimer and some of the nonionic monomers in selective applications. First results obtained with iomeprol-containing liposomal formulations are promising and may foster additional clinical testing.     

Pharmacokinetics and tolerability of iopromide 240 after lumbar myelography.

OBJECTIVE: To evaluate the pharmacokinetics and tolerability of iopromide 240 mg iodine/mL after intrathecal administration. METHODS: Eleven patients with an indication for lumbar myelography received 10 mL iopromide 240 in an open, prospective, single-center study. All patients were followed 72 hours after the procedure and remained in the hospital. Urine was sampled from before the myelography up to 72 hours after the procedure in stages (range, 0-6, 6-12, 12-24, 24-48, and 48-72 hours). Iodine plasma levels were determined before and 30 minutes, 1 hour, 2 hours, 4 hours, 6 hours, 9 hours, 12 hours, and 24 hours after the administration of iopromide 240. Vital signs were measured at baseline, before, and 1 and 24 hours after the procedure. Physical and neurologic examinations were performed in all patients at baseline and at the end of the study period; all adverse events were recorded. The results were subject to pharmacokinetic analysis using compartment model-independent and -dependent methods. RESULTS: Ten of 11 patients had measurable iodine plasma levels. After a lag time of approximately 0.6 hours (mean value), maximum iodine concentrations of 45% of the administered dose per total plasma volume were observed after 3.8 hours. Plasma half-lives ranged from 3.0 to 60.5 hours (model-independent methods) with a mean of 14.9 hours and a standard deviation of 17.0 hours. Using curve fitting with an open one-compartment model revealed good agreement with the model-independent methods (half-life 17.3 hours). The recovery of iodine in urine in the 72-hour period was 78%+/-15% (range, 53%-94%) as a result of an undeterminable loss of urine in some patients and prolonged half-lives in two patients. Only one patient had adverse events 24 hours after myelography. CONCLUSIONS: After lumbar myelography, iopromide 240 is almost completely excreted renally within 72 hours, with a prolonged half-life as a result of the route of administration. The kinetics of iopromide 240 after intrathecal administration are characterized by a prolonged half-life. The safety of the contrast medium was confirmed.     

Contrast medium-induced adverse reactions: economic outcome

Because the cost of managing an expected greater number of adverse reactions when high-osmolality contrast media (HOM) are used could offset the higher material cost of low-osmolality contrast media (LOM), a prospective study was done of 795 inpatients undergoing any of four procedures involving intravascular injection of HOM: cardiac catheterization, peripheral angiography, head computed tomography (CT), or body CT. The resources used in managing HOM-induced adverse reactions were measured, and the costs of these resources were estimated. Four hundred five patients (51%) had adverse reactions. Reactions were grouped into three classes according to their severity. Class 1 (mild) reactions occurred in 358 patients (45%), class 2 (moderate) reactions occurred in 44 patients (6%), and class 3 (severe) reactions occurred in three patients (0.4%). Ninety-nine patients (12%) consumed resources as a result of an adverse reaction. The average cost of these resources per patient undergoing examination was $1.07 to the radiology department, $5.83 to the hospital, and $12.93 to a charge-paying insurer. Mean (+/- standard deviation) cost to the hospital for managing class 1, class 2, and class 3 reactions were $2.52 +/- $5.33, $24 +/- $54, and $910 +/- $749, respectively. By comparison, the difference in material cost of HOM versus LOM ranged from $93 for body CT to $179 for cardiac catheterization. Even if LOM were to induce no adverse reactions, the increased material cost associated with universal substitution of LOM for HOM would be greater than the expected cost of managing adverse reactions when HOM are used.     

Adverse cardiovascular and respiratory events during sedation of pediatric patients for imaging examinations

PURPOSE: To retrospectively identify factors associated with an increased risk of adverse cardiovascular or respiratory events during sedation of pediatric patients for imaging examinations. MATERIALS AND METHODS: This HIPAA-compliant study was institutional review board approved; the requirement for informed consent was waived. All sedation information--including patient demographics, medications (doses and routes of administration), time required to sedate and before discharge, American Society of Anesthesiologists physical status classification, adverse events, and failed sedations--was maintained in a computerized database. A review of the data on all patients sedated between 1997 and 2003 for magnetic resonance imaging, computed tomography, and interventional radiology revealed associated adverse respiratory events in 70 patients. Adverse respiratory event was defined as oxygen desaturation of at least 5%, pulmonary aspiration, and need for airway resuscitation. Adverse cardiovascular events were defined as cardiac arrest and hemodynamic changes requiring medical therapy. Adverse events were compared between sedation regimens--which included fentanyl, chloral hydrate, pentobarbital, and midazolam hydrochloride--by using the Fisher exact test. Multiple logistic regression analysis was applied to identify potential predictors of adverse events. RESULTS: Among 16,467 sedations performed, 70 (0.4%) were associated with adverse respiratory events: 58 cases of oxygen desaturation, two pulmonary aspirations, 10 cases of airway resuscitation, and no cardiovascular events. Nearly 30% (n = 20) of the 70 patients who had an adverse event had a history of serious respiratory illness. Logistic regression analysis revealed that neither patient age, weight, or sex nor type of imaging procedure was associated with an increased risk of an adverse event. Use of a single sedation agent was associated with lower adverse event risk than was use of multiple agents (P < .001). CONCLUSION: Consideration should be given to using single agents, avoiding the use of multidrug sedation regimens, and recognizing that a history of pulmonary disease could be associated with an increased risk of adverse respiratory events despite a currently stable respiratory state.     

Potentially serious adverse events at CT colonography in symptomatic patients: national survey of the United Kingdom

PURPOSE: To retrospectively determine the incidence of potentially serious adverse events associated with computed tomographic (CT) colonography performed in patients with symptoms of colorectal cancer. MATERIALS AND METHODS: Ethical approval and informed consent were waived, since the study was deemed a clinical audit and patients would not be approached. With a national survey in the United Kingdom, all departments offering CT colonography in everyday practice were identified. The lead gastrointestinal radiologist from all responding departments was interviewed, and the frequency of potentially serious adverse events associated with CT colonography performed in patients with symptoms of colorectal cancer, the total number of examinations performed, and technical factors possibly related to perforation were determined. Where a potentially serious adverse event was encountered, it was explored in detail. Responses were collated, and raw frequencies were determined. Fisher exact test was used to determine differences in event rates between groups. RESULTS: At 50 centers, 17 067 CT colonographic examinations (mean number per center, 359; range, 10-3000) were performed. No deaths were reported. Thirteen patients (one [0.08%] of 1313) had had a potentially serious adverse event related to the procedure. There were nine perforations: Four (44%) were asymptomatic and five (56%) were symptomatic, and perforation had an attributable cause, with a symptomatic perforation rate of 0.03% (one in 3413 patients). One patient required laparotomy. An inflated rectal balloon was used to perform 9378 examinations. There was no significant difference between the proportion of perforations associated with rectal balloon inflation (n = 6) and the proportion of those that were not (n = 2) (P = .3). CONCLUSION: Potentially serious adverse events related to CT colonography occurred in 0.08% of symptomatic patients.     

Multi-institution assessment of the use and risk of cardiovascular computed tomography in pediatric patients with congenital heart disease

BackgroundCardiac computed tomography (CT) is increasingly used in pediatric patients with congenital heart disease (CHD). Variability of practice and of comprehensive diagnostic risk across institutions is not known.MethodsFour centers prospectively enrolled consecutive pediatric CHD patients <18 years of age undergoing cardiac CT from January 6, 2017 to 1/30/2020. Patient characteristics, cardiac CT data and comprehensive diagnostic risk were compared by age and institutions. Risk categories included sedation and anesthesia use, vascular access, contrast exposure, cardiovascular medication, adverse events (AEs), and estimated radiation dose.ResultsCardiac CT was performed in 1045 pediatric patients at a median (interquartile range, IQR) age of 1.7 years (0.3, 11.0). The most common indications were arterial abnormalities, suspected coronary artery anomalies, functionally single ventricle heart disease, and tetralogy of Fallot/pulmonary atresia. Sedation was used in 8% and anesthesia in 11% of patients. Peripheral vascular access was utilized for 93%. Median contrast volume was 2 ​ml/kg. Beta blockers were administered in 11% of cases and nitroglycerin in 2% of cases. The median (IQR) total procedural dose length product (DLP) was 20 ​mGy1cm (10, 50). Sedation, vascular access, contrast exposure, use of cardiovascular medications and radiation dose estimates varied significantly by institution and age (p ​< ​0.001). Seven minor adverse events (0.7%) and no major adverse events were reported.ConclusionCardiac CT for CHD is safe in pediatric patients when appropriate CT technology and expertise are available. Scans can be acquired at relatively low radiation exposure with few minor adverse events.     

Injection-associated pain in femoral arteriography: A European multicenter study comparing safety, tolerability, and efficacy of iodixanol and iopromide

Purpose To evaluate injection-associated pain, safety, and efficacy with the isotonic contrast medium iodixanol (Visipaque 270 mg I/ml) compared with iopromide (Ultravist 300 mg I/ml) in femoral arteriography. Methods A multicenter, double-blind, randomized, parallel-group clinical investigation was carried out in 54 hospitals in Europe. Of the patients evaluated, 1225 received iodixanol and 1227 iopromide in conventional and/or digital subtraction angiography. Results The iodixanol group reported statistically significantly less injection-associated pain (0.9%) than the iopromide group (9.5%) (p<0.001). Further, 4.1% in the iodixanol group experienced pain and/or severe heat sensation vs 19.8% in the iopromide group (p<0.001). In the iodixanol group, 1.8% of the patients experienced contrast-related adverse events vs 2.4% in the iopromide group (p=NS). Overall diagnostic information was optimal for 94.1% in the iodixanol group and 95.3% in the iopromide group (p=NS). Conclusions Iodixanol 270 mg I/ml causes significantly less injection-associated pain during femoral arteriography and is as safe and efficatious as iopromide 300 mg I/ml.     

Preoperative percutaneous portal vein embolization: evaluation of adverse events in 188 patients

PURPOSE: To retrospectively assess the frequency of adverse events related to percutaneous preoperative portal vein embolization (PPVE). MATERIALS AND METHODS: Institutional review board did not require its approval or patient informed consent for this study. The adverse events that occurred during PPVE or until planned hepatic surgery was performed or cancelled were retrospectively obtained from clinical, imaging, and laboratory data files in 188 patients (109 male and 79 female patients; mean age, 60 years; range, 16-78 years). Liver resection was planned for metastases (n = 137), hepatocarcinoma (n = 31), cholangiocarcinoma (n = 15), fibrolamellar hepatoma (n = 1), and benign disease (n = 4). PPVE was performed with a single-lumen 5-F catheter and a contralateral approach with n-butyl cyanoacrylate mixed with iodized oil as the main embolic agent. The rate of complications in patients with cirrhosis was compared with that in patients without cirrhosis by using the chi(2) test. RESULTS: Adverse events occurred in 24 (12.8%) of 188 patients, including 12 complications and 12 incidental imaging findings. Complications included thrombosis of the portal vein feeding the future remnant liver (n = 1); migration of emboli in the portal vein feeding the future remnant liver, which necessitated angioplasty (n = 2); hemoperitoneum (n = 1); rupture of a metastasis in the gallbladder (n = 1); transitory hemobilia (n = 1); and transient liver failure (n = 6). Incidental findings were migration of small emboli in nontargeted portal branches (n = 10) and subcapsular hematoma (n = 2). Among the 187 patients in whom PPVE was technically successful, there was a significant difference (P < .001) between the occurrence of liver failure after PPVE in patients with cirrhosis (five of 30) and those without (one of 157). Sixteen liver resections were cancelled due to cancer progression (n = 12), insufficient hypertrophy of the nonembolized liver (n = 3), and complete portal thrombosis (n = 1). CONCLUSION: PPVE is a safe adjuvant technique for hypertrophy of the initially insufficient liver reserve. Post-PPVE transient liver failure is more common in patients with cirrhosis than in those without cirrhosis.     

Acute cardiac tolerance of current contrast media and the new taxane protaxel using iopromide as carrier during porcine coronary angiography and stenting.

RATIONALE AND OBJECTIVES: The systemic tolerance thresholds of modern low-osmolar x-ray contrast media (CM) are similarly high, but their effects on the cardiovascular system and on the coagulation differ. The aim of this study was to comparatively evaluate the cardiovascular tolerability of iopromide, ioxaglate, and iosmin, and of a novel taxane protaxel, dissolved in iopromide, as a carrier, by coronary angiography and stenting. METHODS: Sixteen pigs were randomized into four groups: iosmin (350 mg iodine/mL, n = 4, nonionic dimer), iopromide (370 mg iodine/mL, n = 4, nonionic monomer), ioxaglate (320 mg iodine/mL, n = 4, ionic dimer), and 70-micromol protaxel dissolved in iopromide 370 mg iodine/mL, intended to prevent restenosis. Coronary angiography was performed via the left carotid artery followed by implantation of stents into the left anterior descending and the circumflex arteries. About 80 mL per animal was used in each group. RESULTS: There were no thrombotic complications and no significant adverse events of electrocardiography, blood pressure, or contractility during or after CM injections. There were no differences among the CM tested except that ioxaglate was the only agent showing a significant reduction in dp/dt after 50 seconds compared to iosmin. The values of preinjection parameters were most rapidly regained after iosmin, compared with other CM tested. CONCLUSIONS: The novel iso-osmolar nonionic CM iosmin is well tolerated in porcine coronary angiography and subsequent stenting. The cardiac tolerance of iopromide has not been adversely affected by addition of the cytostatic protaxel.     

Nephrotoxicity of high-osmolality versus low-osmolality contrast media: randomized clinical trial.

The comparative frequency of and risk factors for nephrotoxicity with low-osmolality contrast medium (LOM) versus high-osmolality contrast medium (HOM) were investigated. A randomized, double-blind clinical trial was conducted in patients undergoing diagnostic angiocardiography (n = 430) or contrast material-enhanced body computed tomography (CT) (n = 499). Nephrotoxicity was defined as an increase in serum creatinine level that was greater than both 33% and 0.4 mg/dL (40 mumols/L) above the baseline level within 48 hours after the radiologic procedure. The frequency of nephrotoxicity was similar in patients who received LOM versus those who received HOM: 13 of 479 (2.7%) versus 13 of 450 (2.9%), respectively (P = .87), overall; 4.4% versus 4.0% in angiocardiography patients (P = .84); and 1.2% versus 2.0% in body CT patients (P = .35). Factors associated (P less than .05) with increased risk of nephrotoxicity were insulin-dependent diabetes, baseline serum creatinine level greater than 1.5 mg/dL (130 mumols/L), concurrent use of furosemide, and angiocardiographic examination. Patients who have preexisting renal insufficiency may be at higher risk for nephrotoxicity with HOM than with LOM.     

Glomerular filtration rate measured by using triphasic helical CT with a two-point Patlak plot technique

PURPOSE: To determine the accuracy of the two-point Patlak plot in the calculation of glomerular filtration rate (GFR). MATERIALS AND METHODS: Fifty patients without acute renal disorder were included. GFR was calculated by using a two-point Patlak plot technique. The computed tomography (CT) protocol consisted of a plain examination followed by two contrast material-enhanced examinations in the arterial and portovenous phase. Each examination included the entire kidneys and was performed after injection of 120 mL iopromide and 300 mg of iodine per milliliter given per 75 kg of body weight. All examinations were performed with a standard abdominal protocol. Section thickness was 4 x 2.5 mm, and table advance was 12.5 mm. Bolus triggering commenced 10 seconds after the start of contrast medium injection. Twelve dynamic scans were obtained with reduced tube current every 3 seconds to obtain sufficient arterial input function data. Correction for hematocrit level was made by using the unenhanced attenuation of the aorta. As a reference method, plasma clearance of the contrast medium injected for CT was calculated from three iodine plasma concentration measurements obtained 3, 4, and 5 hours after injection. Linear correlation was performed. RESULTS: GFR was calculated from CT data in 48 patients. Two patients were excluded because of breathing errors. Mean GFR was 80 mL/min (range, 17-153 mL/min) as measured with iopromide plasma clearance and 82 mL/min (range, 28-148 mL/min) as measured with CT. Linear correlation between the two methods was r = 0.889; GFR calculated with the two-point Patlak plot was equal to 15 plus 0.83 times GFR (plasma clearance). The mean difference between GFRs as determined with the two methods was -1.2 mL/min (95% CI: -27.1, 24.6). CONCLUSION: Total GFR can be measured accurately with minimally extended triphasic CT in patients without acute renal disorder by using a two-point Patlak plot technique.