[Effectiveness of nephroprotection by the selection of contrast media used during vascular interventions in patients with chronic renal failure?]. / Ist Nephroprotektion durch die Auswahl des Röntgen-Kontrastmittels im Rahmen von Gefäßinterventionen bei vorbestehender Niereninsuffizienz möglich?

BACKGROUND: The increasing number of endovascular procedures made aware of a kidney disease induced by contrast media (CM). Contrast-induced nephropathy (= CIN) can develop in 0.6-44 % of the treated patients by angiography and / or endovascular intervention. The incidence in high-risk patients ranges from 50 to 70 %. In most cases CIN is inconspicuous and reversible. But pre-existing chronic kidney disease, diabetes mellitus, age and variable different risk factors (e. g., PAOD) can induce irreversible renal impairment. The purpose of the presented trial is to investigate incidence, predictors, and out-come of CIN in chronic renal failure patients using two different CM; one non-ionic isoosmolar -iodixanol and the other non-ionic low-osmolar iopromide. METHODS: To evaluate the incidence of CIN after endovascular diagnostics and intervention two collectives of 100  patients with chronic renal insufficiency were treated with different contrast media (CM). Inclusion followed prospectively in two collectives. One collective received iopromide (Ultravist™, Bayer Health Care, Lever-kusen, Germany), and the second hundred patients received iodixanol (Visipaque™, Nycomed Amersham, Princeton, New Jersey). Demographics, comorbidities, procedure-related data were completed by serum creatinine levels and GFR (= glomerular filtration rate). Inclusion criteria were a serum creatinine level ≥ 1.5 mg% and a GFR ≤ 60 mL / min. Those parameters were measured twice pre-interventionally, and one time 48-72  hours after the endovascular procedure. RESULTS: Collectives were homogenous and comparable concerning pre-existing risk factors, age and gender. Renal function stayed at a constant level and was independent of contrast medium selection, repectively. Average creatinine levels ranged around 1.77 mg% ±â€Š0.75  standard deviation (SD) pre-interventionally; postinterventional measurement exposed a creatinine level of 1.74 mg% ±â€Š0.74 SD as mean of both collectives. GFR (preinterventional 39.64 mL / min ±â€Š12.48 SD) increased non-significantly to 45.48 mL / min ±â€Š16.82 SD. Pre-existing chronic kidney disease had no effect on renal function parameters; no other risk factors could be evaluated. CONCLUSION: According to cost-effectiveness a low-osmolar monomeric contrast medium (LOCM) is a sufficient selection, under careful renal function control.

A systematic review of cost-effectiveness analyses across the acute kidney injury landscape.

Introduction: Acute kidney injury (AKI) is a complex and common condition associated with increased morbidity, mortality, and costs. Evidence from cost-effectiveness analysis (CEA) have targeted various aspects of AKI including detection with biomarkers, treatment with renal replacement therapy, and prevention when using contrast media. However, there has not been a systematic review of these studies across the entirety of AKI.Areas covered: PubMed, Embase, and Cochrane library were used to identify CEA studies that involved AKI from 2004 onwards. These studies compared AKI treatment through renal replacement therapies (n = 6), prevention of contrast-induced-AKI (CI-AKI) using different media (n = 3), and diagnosis with novel biomarkers (n = 2). Treatment strategies for AKI focused on continuous versus intermittent renal replacement therapy. While there was no consensus, the majority of studies favored the continuous form. For contrast media, both studies found iodixanol to be cost-effective compared to iohexol for preventing CI-AKI. Additionally, novel biomarkers showed potential to be cost-effective in risk assessment and detection of AKI.Expert opinion: Consistent criteria such as a lifetime time horizon would allow for better model comparisons. Further research on clinical parameters to capture transition probabilities between stages within AKI and progression to downstream kidney disease is needed.

Imaging the oesophagus after penetrating cervical trauma using water-soluble contrast alone: simple, cost-effective and accurate.

AIM: This audit aims to gauge the safety and efficacy of iso-oncotic water-soluble contrast media as the sole imaging evaluation of the distal pharynx and cervical oesophagus after penetrating cervical trauma. METHODS: A retrospective audit was performed over a 4-year period of all patients with penetrating cervical trauma to zones 1 and 2 of the neck who were subjected to imaging evaluation as part of a selective non-operative management policy for penetrating cervical trauma. The outcome was reviewed and the sensitivity, specificity and predictive values of the investigation were determined. The surgical management of identified injuries is also described. RESULTS: Four hundred and sixty-five contrast studies were included with 11 studies positive for pathology (9 injuries, 2 incidental findings). Surgery was undertaken in 4 patients with cervical oesophageal injuries and conservative management was carried out in 5 cases of distal pharyngeal injury. No missed injuries and no significant adverse events were identified during the study period. CONCLUSION: A contrast study of the oesophagus with water-soluble iso-oncotic contrast media as the sole diagnostic imaging modality is safe (avoiding the risk of aspiration pneumonia), reliable (identifying all injuries) and cost-efficient (avoiding the need for additional expensive investigations) in cases of penetrating cervical trauma.

Weight-adapted iodinated contrast media administration in abdomino-pelvic CT: Can image quality be maintained?

INTRODUCTION: In many centres, a fixed method of contrast-media administration is used for CT regardless of patient body habitus. The aim of this trial was to assess contrast enhancement of the aorta, portal vein, liver and spleen during abdomino-pelvic CT imaging using a weight-adapted contrast media protocol compared to the current fixed dose method. METHODS: Thirty-nine oncology patients, who had previously undergone CT abdomino-pelvic imaging at the institution using a fixed contrast media dose, were prospectively imaged using a weight-adapted contrast media dose (1.4 ml/kg). The two sets of images were assessed for contrast enhancement levels (HU) at locations in the liver, aorta, portal vein and spleen during portal-venous enhancement phase. The t-test was used to compare the difference in results using a non-inferiority margin of 10 HU. RESULTS: When the contrast dose was tailored to patient weight, contrast enhancement levels were shown to be non-inferior to the fixed dose method (liver p < 0.001; portal vein p = 0.003; aorta p = 0.001; spleen p = 0.001). As a group, patients received a total contrast dose reduction of 165 ml using the weight-adapted method compared to the fixed dose method, with a mean cost per patient of £6.81 and £7.19 respectively. CONCLUSION: Using a weight-adapted method of contrast media administration was shown to be non-inferior to a fixed dose method of contrast media administration. Patients weighing 76 kg, or less, received a lower contrast dose which may have associated cost savings. A weight-adapted contrast media protocol should be implemented for portal-venous phase abdomino-pelvic CT for oncology patients with adequate renal function (>70 ml/min/1.73 m2).

[Oral administration of intravenous contrast media: a tasty alternative to conventional oral contrast media in computed tomography]. / Intravenöse Kontrastmittel oral appliziert: Eine wohlschmeckende Alternative zum herkömmlichen oralen Kontrastmittel in der Computertomografie.

PURPOSE: Many patients dislike oral contrast media due to their bad taste. The aim of the present study was to identify a solution that tastes better while providing the same opacification in order to offer oncological patients an alternative to the routinely used bad tasting oral contrast media. MATERIALS AND METHODS: In a single blinded, prospective clinical study, the orally administered intravenous contrast media iohexol (Omnipaque), iopromide (Ultravist), and iotrolan (Isovist) as well as the oral contrast media sodium amidotrizoate (Gastrografin) and ioxithalamate (Telebrix) were each compared to the oral contrast medium lysine amidotrizoate as the reference standard at a constant dilution. The density values of all contrast media with the same dilutions were first measured in a phantom study. The patient study included 160 patients who had undergone a prior abdominal CT scan with lysine amidotrizoate within 6 months. The patients rated their subjective taste impression on a scale of 0 (very bad) to 10 (excellent). In addition, adverse events and opacification were recorded and prices were compared. RESULTS: The phantom study revealed identical density values. Patients assigned much higher taste impression scores of 8 and 7 to iohexol and iotrolan, respectively, as compared to a score of 3 for the conventional lysine amidotrizoate (p< 0.05). Iopromide and sodium amidotrizoate did not differ significantly from lysine amidotrizoate. The opacification of all contrast media and experienced adverse events did not differ significantly. Iotrolan (ca. 120 euro/100 ml), Iohexol and Iopromide (ca. 70 euro/100 ml) are more expensive than the conventional oral contrast media (ca. 10 - 20 euro/100 ml). CONCLUSION: Orally administered solutions of non-ionic contrast media improve patient comfort due to the better taste and provide the same opacification in comparison to conventional oral contrast media. At present, their use should be limited to individual cases due to the higher costs.

Net costs from three perspectives of using low versus high osmolality contrast medium in diagnostic angiocardiography.

OBJECTIVES: We conducted an economic analysis to assess the extent to which a reduction in adverse drug reactions induced by low osmolality compared with high osmolality contrast media during diagnostic angiocardiography would result in savings to hospitals, society and third-party payers that would offset the substantially higher price of low osmolality contrast medium. BACKGROUND: Substitution of low osmolality for high osmolality contrast media in the approximately 1 million diagnostic angiocardiographic procedures performed each year in the United States could substantially increase health care costs. Cost-effectiveness estimates should include savings that might occur through reduced costs of managing adverse drug reactions. METHODS: In a randomized clinical trial of 505 persons under-going diagnostic angiography with either high osmolality or low osmolality contrast medium, we measured and compared 1) material costs of contrast media, and 2) costs from three perspectives of incremental resources used to manage contrast-related adverse drug reactions. We also performed sensitivity analyses to examine the effect of different assumptions with regard to relative risk, absolute risk and costs of adverse drug reactions on estimates of net cost of use of high osmolality and low osmolality contrast media. RESULTS: One-hundred thirty-seven (54.2%) of 253 patients receiving high osmolality contrast medium and 44 (17.5%) of 252 patients receiving low osmolality contrast medium experienced adverse drug reactions. The average cost (from society's perspective) of resources used to manage adverse drug reactions per patient undergoing angiography was significantly (p = 0.0001) greater for high osmolality (mean $249) versus low osmolality (mean $92) contrast medium. Differential costs (from the hospital's perspective) were $67 greater for high osmolality contrast medium. Charges and professional fees (from the payer's perspective) were $182 greater for high osmolality (mean $312) than for low osmolality (mean $130) contrast medium (p = 0.42, NS). The higher differential and average costs of managing adverse drug reactions with high osmolality contrast medium offset 33% and 75%, respectively, of the $207 difference in mean material costs, but these estimates are sensitive to infrequent high cost cases. CONCLUSIONS: Although low osmolality contrast medium is not cost-saving in diagnostic angiocardiography, its higher price is partially offset by lower management costs of adverse drug reactions. The cost offset for the hospital is lower than that for society and may not be realized by third-party payers. These methods and results may be useful in establishing clinical and payment guidelines for use of alternative contrast media in diagnostic angiocardiography.

Cost-effectiveness of iodixanol in patients at high risk of contrast-induced nephropathy.

BACKGROUND: Acute renal failure after contrast-induced nephropathy is a clinically important and costly complication after the use of iodine-based contrast media. We investigated the cost and cost-effectiveness of 2 contrast media in patients at high risk of contrast-induced nephropathy. METHODS: The analyses were based on a randomized, prospective, multinational clinical study comparing the nephrotoxic effects of an isosmolar nonionic contrast medium, iodixanol, with those of a low-osmolar nonionic contrast medium, iohexol. Resource utilization data were obtained from the study and from a retrospective review of patients' hospital records. Swedish, German, and French unit prices were applied to resources used. Between-group differences in average costs were analyzed using a nonparametric bootstrap method. RESULTS: Resource utilization data for 125 patients were analyzed. Seven contrast media-related serious adverse reactions, of which 6 were acute renal failures, were noted in 6 patients receiving iohexol. Two patients in the iodixanol group had 1 nonserious reaction each. The mean hospitalization cost per patient was Euros 489, Euros 573, and Euros 393 lower after iodixanol than after iohexol using Swedish, German, and French unit prices, respectively. The mean per-patient costs of treating adverse drug reactions were Euros 371, Euros 399, and Euros 445 lower after iodixanol than after iohexol, using the respective unit prices (P < or = 0.01). Iodixanol was cost-effective compared with iohexol, with both lower costs and better effects related to fewer adverse drug reactions. CONCLUSIONS: The isosmolar contrast medium iodixanol appears to be cost-effective when compared with a low-osmolar contrast medium, iohexol, in diabetic patients with renal impairment undergoing angiography.

[Contrast media in peripheral angiography: does cost reduction mean loss of quality and safety? A reevaluation based on a randomized double-blind comparative study of ioxaglate versus iopromide]. / Kontrastmittel in der peripheren Angiographie: Bedeutet Kostenreduktion Verlust an Qualität und Sicherheit? Eine Reevaluierung anhand einer randomisierten Doppelblind-Vergleichsstudie von Ioxaglat versus Iopromid.

PURPOSE: To evaluate whether meglumine-sodium-ioxaglate (Hexabrix) and iopromide (Ultravist) are identically appropriate for peripheral angiography. Outcome variables were pain, image quality and adverse events. METHODS: Sixty patients were included in a randomised double-blind study. In all patients an intraarterial digital subtraction angiography (i.a. DSA) of iliac and peripheral arteries was performed. RESULTS: Analysis of the study revealed no significant difference between both contrast media in terms of the main and additional outcome variables. In comparison to iopromide, ioxaglate caused milder pain sensations (VAS 4.70 vs. 7.76, p = 0.25). Mild adverse events were observed more frequently in ioxaglate angiography (11% vs. 0%, p = 0.1). CONCLUSION: Both contrast media seem to be appropriate for peripheral angiography using DSA technique. Ioxaglate causes a cost reduction of about 20-35%. However, an increase of mild adverse reactions up to 11% to 15% has to be accepted.

Cost and validity of early postoperative contrast swallow after laparoscopic adjustable gastric banding.

BACKGROUND: To assess the validity and cost of early routine upper gastrointestinal (UGI) studies after laparoscopic adjustable gastric banding (LAGB) at a university hospital in the United States. Today, although there is widespread use of LAGB, and it is considered a safe procedure, it also can result in some specific early complications. In most centers, an UGI series after bariatric surgery is performed to rule out these potentially dangerous complications. METHODS: From March 2006 to July 2010, 183 LAGB procedures were performed by a single surgeon. All data were collected prospectively in a computerized database and reviewed retrospectively. The patients underwent water-soluble UGI studies during the early postoperative phase (2-24 h) to exclude gastrointestinal perforation, obstruction, and gastric band malposition. RESULTS: No intraoperative complications occurred. One conversion to an open procedure was required because of massive adhesions. A total of 21 postoperative complications (11.5%) occurred. None of the 183 patients who underwent an early UGI series experienced leakage, gastric band malposition, or slippage. The only radiologic abnormality was a stomal obstruction (.5%) requiring reoperation. The total cost for the 183 UGI studies was $54,900. The mean hospital stay was .5 day (range .1-5.6). Approximately 90% of patients were discharged within the first 24 hours. CONCLUSION: The fear of acute perforation or obstruction has been the rationale for obtaining UGI studies after LAGB. We found this to be expensive and of limited value in an experienced center and have created a decisional algorithm to determine when its use is appropriate for symptomatic patients.

Cost-effectiveness of iso- versus low-osmolality contrast media in outpatients with high risk of contrast medium-induced nephropathy.

INTRODUCTION: Contrast media can cause acute renal failure by direct toxic effects on the tubular cells and kidney ischemia. Diabetics and hospitalized patients have a greater risk of developing contrast-induced nephropathy than the general population. OBJECTIVE: The cost effectiveness of iso and low-osmolality contrast media was assessed in high risk outpatients. MATERIALS AND METHODS: The analysis was based on a systematic literature review comparing the nephrotoxic effects of iso- to low-osmolality contrast media. Only direct costs were considered; these were obtained from the official tariff manual. Incremental cost-effectiveness ratios, efficiency curves and acceptability curves were calculated. Univariate sensitivity analyses were performed for costs and effects, as well as probabilistic analyses. Zero and 3% discounts were applied to results. The cost-effectiveness threshold was equal to the per capita GDP per life-year gained. RESULTS: Alternatives with Iopamidol and Iodixanol are preferable to the others, because both reduce risk of contrast-induced nephropathy and are less costly. The incremental cost-effectiveness of the Iodixanol alternative compared to the Iopamidol alternative is US$ 14,660 per additional life year gained; this is more than twice the threshold. CONCLUSION: The low-osmolality contrast medium, Iopamidol, appears to be cost-effective when compared with Iohexol or other low-osmolality contrast media (Iopromide, Iobitridol, Iomeprol, Iopentol and Ioxilan) in contrast-induced nephropathy, high-risk outpatients. The choice of the iso-osmolality contrast medium, Iodixanol, depends on its cost per vial and on the willingness to pay.

Contrast and cost savings by implementation of a multidose bulk IV contrast delivery system.

PURPOSE: In an effort to standardize clinical operations and reduce intravenous (IV) contrast costs, the authors' department switched from 100-mL single-use IV contrast vials to a multidose IV contrast delivery system using iopromide 370. The purpose of this study was to assess IV contrast use, waste, and cost savings resulting from the implementation of this multidose system. METHODS: A review was conducted of consecutive pulmonary embolism (PE) CT angiography, head and neck (HN) CT angiography, and abdomen/pelvis (AP) CT examinations performed according to standard department protocol 2 weeks before and 2 weeks after the implementation of a multidose IV contrast delivery system. The amount of contrast loaded and injected for each examination was recorded, and total contrast used and wasted were calculated. Volumes of used and wasted contrast were compared before and after implementation using Wilcoxon's rank-sum test. Associated cost savings are reported. RESULTS: There were 32 PE, 27 HN, and 124 AP examinations performed using the 100-mL single-use vial technique and 27 PE, 25 HN, and 175 AP examinations using the multidose technique. Use of the multidose system resulted in average reductions in used contrast volume of 15.9, 35.1, and 11.4 mL, respectively, for PE, HN, and AP examinations (Wilcoxon's P < .0001). For PE and HN examinations, this was due to reduced contrast waste, as these protocols require less than the 100-mL contents of the single-use vial. For AP examinations, savings were due to reduction in contrast volume through the use of higher iodine concentration. Associated cost savings annualize to approximately $31,800 for these 3 examination types alone at the authors' institution. CONCLUSION: The implementation of a multidose bulk IV contrast material delivery system results in significant contrast and cost savings.

Cost-effectiveness of iso- versus low-osmolality contrast media in outpatients with high risk of contrast medium-induced nephropathy / Costo-efectividad de medios de contraste isoosmolales e hiposmolales en pacientes con alto riesgo de nefropatía inducida por medio de contraste

Introduction. Contrast media can cause acute renal failure by direct toxic effects on the tubular cells and kidney ischemia. Diabetics and hospitalized patients have a greater risk of developing contrast-induced nephropathy than the general population. Objective. The cost effectiveness of iso and low-osmolality contrast media was assessed in high risk outpatients. Materials and methods. The analysis was based on a systematic literature review comparing the nephrotoxic effects of iso- to low-osmolality contrast media. Only direct costs were considered; these were obtained from the official tariff manual. Incremental cost-effectiveness ratios, efficiency curves and acceptability curves were calculated. Univariate sensitivity analyses were performed for costs and effects, as well as probabilistic analyses. Zero and 3% discounts were applied to results. The cost-effectiveness threshold was equal to the per capita GDP per life-year gained. Results. Alternatives with Iopamidol and Iodixanol are preferable to the others, because both reduce risk of contrast-induced nephropathy and are less costly. The incremental cost-effectiveness of the Iodixanol alternative compared to the Iopamidol alternative is US$ 14,660 per additional life year gained; this is more than twice the threshold. Conclusion. The low-osmolality contrast medium, Iopamidol, appears to be cost-effective when compared with Iohexol or other low-osmolality contrast media (Iopromide, Iobitridol, Iomeprol, Iopentol and Ioxilan) in contrast-induced nephropathy, high-risk outpatients. The choice of the iso-osmolality contrast medium, Iodixanol, depends on its cost per vial and on the willingness to pay.

Introducción. Los medios de contraste pueden provocar falla renal aguda por toxicidad directa sobre las células tubulares e isquemia medular renal. Los pacientes diabéticos y los hospitalizados presentan mayor riesgo de desarrollar nefropatía inducida por medios de contraste que la población general. Objetivo. Establecer el costo-efectividad de los medios de contraste isosmolales e hiposmolales en pacientes con alto riesgo. Materiales and métodos. El análisis se basó en una revisión sistemática de la literatura científica, comparando los efectos nefrotóxicos de los medios isosmolales e hipoosmolales. Se consideraron sólo los costos directos, obtenidos del manual tarifario. Se calcularon las tasas del incremento del costo-efectividad, las curvas de eficiencia y de aceptabilidad. Se hicieron análisis univariados de sensibilidad para costos y efectos, así como probabilísticos. Se aplicaron tasas de descuento de 0 y 3 % a los resultados. Se usó como umbral de costo-efectividad por año de vida ganado, el producto interno bruto per cápita. Resultados. Las alternativas con Iopamidol y Iodixanol dominan a las demás porque reducen el riesgo de nefropatía inducida por contraste a un menor costo. La razón del incremento del costo-efectividad del iodixanol comparado con el iopamidol es de US$ 14.660 por año de vida ganado que más que duplica el umbral. Conclusión. El medio de baja osmolalidad, iopamidol, parece ser costo-efectivo comparado con iohexol u otros medios hiposmolares (iopromide, iobitridol, iomeprol, iopentol y ioxilan), en pacientes con alto riesgo de nefropatía inducida por contraste. La elección del medio hiposmolar, depende de la disponibilidad a pagar o del costo por ampolleta.

Safety and cost effectiveness of high-osmolality as compared with low-osmolality contrast material in patients undergoing cardiac angiography.

BACKGROUND AND METHODS: Low-osmolality contrast agents produce fewer hemodynamic and electrophysiologic alterations during cardiac angiography, but they are 20 times more expensive than high-osmolality contrast agents. In a randomized, double-blind trial comparing a nonionic low-osmolality contrast agent (Omnipaque 350) with a high-osmolality agent that does not avidly bind calcium (Hypaque 76) in 505 patients undergoing cardiac angiography, we determined the incidence of minor, mild, moderate, and severe adverse reactions, identified risk factors for such reactions, and evaluated the cost effectiveness of various strategies for the use of contrast material. RESULTS: The 253 patients who received a high-osmolality contrast agent were three times more likely to have a moderate adverse reaction (95 percent confidence interval for the relative risk, 1.6 to 5.5) but no more likely to have a severe reaction (95 percent confidence interval, 0.2 to 2.3) than the 252 patients who received a low-osmolality agent. All 10 severe reactions occurred in patients who were older than 60 years or had unstable angina. Patients with these characteristics were also 3.5 times more likely (95 percent confidence interval, 1.8 to 6.8) to have a moderate reaction (44 of 310 patients, or 14 percent) than those without either characteristic (8 of 195 patients, or 4 percent). We estimated that the incremental cost of each moderate reaction avoided would be $1,698 with a strategy that involved giving a low-osmolality contrast agent only to patients who were over 60 years of age or had unstable angina, instead of giving a high-osmolality agent to all patients. The incremental cost per moderate reaction avoided by giving a low-osmolality contrast agent to all patients rather than only to those over 60 or with unstable angina would be $5,842. CONCLUSIONS: The use of contrast agents with low rather than high osmolality during cardiac angiography reduces the risk of moderate, but not of severe, adverse reactions to the agent used. A strategy of reserving low-osmolality contrast agents for use in patients at high risk for adverse reactions would be more cost effective than one requiring their use in all patients.

Cost-effective use of low-osmolality contrast media for CT of the liver: evaluation of liver enhancement provided by various doses of iohexol.

OBJECTIVE: Because of pending efforts to reform health care in the United States, judicious use of low-osmolality contrast media is important. We studied the effects of using various concentrations and volumes of iohexol, compared with the conventional dose and concentration of diatrizoate meglumine used for CT, to determine if a more cost-effective dose results in diagnostically efficacious liver enhancement. SUBJECTS AND METHODS: A total of 902 patients received one of nine different doses of IV contrast media. Eight doses of iohexol were used: 125 ml of iohexol 350 (350 mg l/ml, 44 g l/dose), 100 ml of iohexol 350 (35 g l/dose), 150 ml of iohexol 300 (300 mg l/ml, 45 g l/dose), 120 ml of iohexol 300 (36 g l/dose), 100 ml of iohexol 300 (30 g l/dose), 175 ml of iohexol 240 (240 mg l/ml, 42 g l/dose), 150 ml of iohexol 240 (36 g l/dose), and 125 ml of iohexol 240 (30 g l/dose). A single dose (150 ml) of diatrizoate meglumine 60% (w/v) was used (42 g l/dose). Contrast material was injected at a rate of 2 ml/sec. Scanning began 35-45 sec after injection. Quantitative analysis of enhancement was performed by obtaining region-of-interest measurements through the liver on scans obtained before and after injection of contrast material. Mean and maximum changes in hepatic density and mean time to maximum enhancement were measured. Mean time-density curves were subsequently derived for each dose of contrast material. Qualitative analysis of enhancement was performed by using subjective, previously defined criteria. All studies were interpreted in a double-blind fashion. RESULTS: Mean hepatic enhancement was greater with 125 ml of iohexol 350 and 150 ml of iohexol 300 than with other doses of contrast material (p < .05). Both 125 ml of iohexol 350 and 150 ml of iohexol 300 produced actual hepatic enhancement of more than 50 H for over 60 sec. The greatest maximum increase in hepatic density occurred with 125 ml of iohexol 350. When analyzed qualitatively, 150 ml of iohexol 300 resulted in the highest percentage of optimum enhancement. CONCLUSION: According to quantitative analysis, 125 ml of iohexol 350 administered at a rate of 2 ml/sec produces the best enhancement, whereas according to qualitative analysis, 150 ml of iohexol 300 produces the best enhancement. All doses of iohexol 240 provide poor enhancement compared with a conventional dose of contrast material of 150 ml of diatrizoate meglumine 60% or 150 ml of iohexol 300. A moderate cost savings can be achieved by using 125 ml of iohexol 350 for dynamic sequential CT.

Quantitative and qualitative evaluation of volume of low osmolality contrast medium needed for routine helical abdominal CT.

OBJECTIVE: The purpose of our study was to determine the minimum optimal dose of IV contrast medium for helical CT that can preserve image quality while reducing cost. SUBJECTS AND METHODS: Four hundred sixty-three patients from six centers were enrolled in a prospective trial in which patients were randomized into one of four weight-based dose categories of iopromide, 300 mg I/mL: 1.25, 1.50, 1.75, and 2.0 mL/kg. Six of 463 patients were excluded from analysis. A radiologist at each center who was unaware of the volume of contrast medium administered determined whether the scans were acceptable. The responses were analyzed by dose, in aggregate, and by weight. Enhancement values (in Hounsfield units) in regions of interest in the liver, pancreas, aorta, and kidneys were obtained at a single time during the scan. The participating radiologist was unaware of these values. Finally, three additional nonparticipating site observers assessed the images for acceptability, diagnostic quality, and overall level of confidence. A cost model comparing incurred charges in using 150 or 100 mL, or 1.5 mL/kg, of low osmolality contrast medium was developed from experience in an additional 303 patients. RESULTS: We found no clinically significant difference in acceptability of scans at doses greater than 1.5 mL/kg. However, significant variability occurred among the centers. The use of 1.5 mL/kg led to a savings of $9927.16 for 303 patients when compared with the use of 150 mL at list price. The cost is the same for 1.5 mL/kg or use of 100 mL of contrast medium. CONCLUSION: A weight-based dose at 1.5 mL/kg of low osmolality contrast medium can provide acceptable scans in most patients, with a significant cost savings.

Using a saline chaser to decrease contrast media in abdominal CT.

OBJECTIVE: The purpose of this study was to compare hepatic tumor conspicuity on CT after injection of either 150 mL of contrast material or 100 mL of contrast material plus a 50-mL saline chaser. SUBJECTS AND METHODS: We evaluated 86 hypoattenuating liver metastases in 26 patients. Patients underwent CT in two sessions separated by a mean of 85 days: one time with 150 mL of contrast material and the other time with 100 mL of contrast material followed by a 50-mL saline chaser. The order of the sessions was randomized. Contrast material was administered via power injector and matched for injection rate and delay time. Attenuation values were obtained from normal liver tissue and metastases and from the spleen, kidney, aorta, and inferior vena cava. RESULTS: The 150 mL dose of contrast material caused slightly greater liver and tumor attenuation than 100 mL of contrast material with a chaser (mean hepatic attenuation, 95.6 vs 89.8 H, respectively; p < 0.03, paired t test; mean tumor attenuation, 53.2 vs 49.1 H, respectively; r = 0.71, p = 0.09). The difference in conspicuity of liver lesions was slightly greater with 150 mL than with 100 mL with a chaser (46.8 H vs 44.2 H; r = 0.46, p = 0.08, paired t test), but was of doubtful clinical significance (2.6 H). Kidney, spleen, and vascular structures enhanced more with 150 mL than with 100 mL and a chaser. CONCLUSION: Using 100 mL of contrast material and a saline chaser did not result in a meaningful difference in liver parenchyma attenuation or lesion conspicuity compared with using 150 mL of contrast medium alone. Routine use of a chaser for abdominal CT may yield cost savings and a decreased risk of contrast nephropathy.

Selective use of low-osmolality contrast agents for i.v. urography and CT: safety and effect on cost.

OBJECTIVE: The purpose of this study was to determine if the selective use of low-osmolality contrast material for excretory urography and CT is safe and if it saves money. MATERIALS AND METHODS: At the University Medical Center in Tucson, a questionnaire was developed to identify high-risk patients who would benefit from the use of a low-osmolality contrast agent. High-risk patients were defined as those with a history of a reaction to contrast material, severe allergies, asthma, severe cardiac disease, multiple myeloma, sickle cell disease, polycythemia, pheochromocytoma, or renal impairment. Beginning in March 1993, the questionnaire was given to all adult outpatients scheduled for daytime excretory urography and routine CT studies of the head and body. Only patients identified as high risk were given a low-osmolality (non-ionic) contrast agent. All other patients received high-osmolality (ionic) contrast material. The contrast agent chosen for a patient was determined by the person administering the questionnaire, usually a radiologic technologist. RESULTS: From March 1993 through December 1993, 1114 adult daytime outpatient excretory urographic and contrast-enhanced CT studies were examined at our institution. In 235 (21%) of the studies, a low-osmolality agent was used and in 879 (79%) studies, a high-osmolality agent was used. This represented a reduction in the use of low-osmolality agents from more than 90% of patients to 21%, an annual cost reduction from $288,000 to $60,480. We observed no untoward reactions to contrast material that could be specifically attributed to the increased use of high-osmolality agents. CONCLUSIONS: Selective use of low-osmolality contrast agents during excretory urography and CT can provide substantial cost savings and is not associated with a significant risk of major complications.