Computed Tomography Angiography versus Digital Subtraction Angiography as a Primary Diagnostic Tool in Nontraumatic Subarachnoid Hemorrhage: Cost-Effectiveness Analysis Study.

BACKGROUND: Digital subtraction angiography (DSA) and computed tomographic angiography (CTA) are used to identify the cause of nontraumatic subarachnoid hemorrhage (SAH). There is no consensus on which to choose as the first diagnostic tool. We aimed to compare the cost-effectiveness of CTA versus DSA as a primary tool for identifying the cause of nontraumatic SAH. METHODS: A decision analysis model was built to simulate patients undergoing DSA or CTA as a primary diagnostic tool for the cause of nontraumatic SAH. The input data for the study were extracted from literature. Probabilistic and deterministic sensitivity analyses were performed to evaluate the robustness of the model. RESULTS: In the base case calculation, it cost $1261.82 less and yielded 0.0001 quality-adjusted life year (QALY) when DSA was used as a primary diagnostic imaging tool for nontraumatic SAH. Choosing DSA as a primary tool was cost-effective in more than 65% of iterations in probabilistic sensitivity analysis. Deterministic sensitivity analyses show when the probability of using endovascular treatment is >47.2%, choosing DSA is more cost-effective; otherwise, CTA is more optimal. CTA is more cost-effective when the cost for DSA >2.6 × CTA + $600. CONCLUSIONS: Based on current literature and our model DSA as a primary diagnostic tool for the cause of nontraumatic SAH is more cost-effective. However, in clinical practice physicians can choose either DSA or CTA according to the scale of endovascular procedures used in their center, as well as the cost correlation between CTA and DSA, which varies among institutions.

Repositioning of central venous access devices using a high-flow flush technique - a clinical practice and cost review.

BACKGROUND: Malpositioned central venous access device (CVAD) tip locations can cause significant mechanical and chemical vessel-related injuries and complications if left in inappropriate positions.The aim of this study is to determine the use of a high-flow flush technique (HFFT) in successful correction of malpositioned catheters into the lower superior vena cava or cavoatrial junction and provide a cost comparison to interventional/fluoroscopic-based repositioning. METHODS: This is a retrospective chart and radiographic review of all inserted CVADs found malpositioned between 1996-2014 in a multi-specialty 1000-bed tertiary trauma center in Sydney, Australia.7450 CVADs placed by a nurse-led vascular access service were reviewed. Catheters repositioned pre-2010 were excluded owing to radiology repositioning interventions. RESULTS: There were 3996 peripherally inserted central catheters (PICCs) and 3454 centrally inserted central catheters (CICCs) placed. Seventy-four were malpositioned post-2010. Of these, 53 devices were repositioned using the studied technique; 86% (46/53) of catheters were successfully repositioned on the first HFFT attempt. There was supportive evidence that device insertion side is important in potential catheter malposition. CONCLUSIONS: Clinical outcomes suggest that CICCs and PICCs may be successfully repositioned utilizing this technique, with no adverse events associated and a prospective cost saving benefit when compared to interventional-based repositioning procedures.

The accuracy and cost-effectiveness of strategies used to identify peripheral artery disease among patients with diabetic foot ulcers.

BACKGROUND: Patients with diabetic foot ulcers (DFUs) should be evaluated for peripheral artery disease (PAD). We sought to estimate the overall diagnostic accuracy for various strategies that are used to identify PAD in this population. METHODS: A Markov model with probabilistic and deterministic sensitivity analyses was used to simulate the clinical events in a population of 10,000 patients with diabetes. One of 14 different diagnostic strategies was applied to those who developed DFUs. Baseline data on diagnostic accuracy of individual noninvasive tests were based on a meta-analysis of previously reported studies. The overall sensitivity and cost-effectiveness of the 14 strategies were then compared. RESULTS: The overall sensitivity of various combinations of diagnostic testing strategies ranged from 32.6% to 92.6%. Cost-effective strategies included ankle-brachial indices for all patients; skin perfusion pressures (SPPs) or toe-brachial indices (TBIs) for all patients; and SPPs or TBIs to corroborate normal pulse examination findings, a strategy that lowered leg amputation rates by 36%. Strategies that used noninvasive vascular testing to investigate only abnormal pulse examination results had low overall diagnostic sensitivity and were weakly dominated in cost-effectiveness evaluations. Population prevalence of PAD did not alter strategy ordering by diagnostic accuracy or cost-effectiveness. CONCLUSIONS: TBIs or SPPs used uniformly or to corroborate a normal pulse examination finding are among the most sensitive and cost-effective strategies to improve the identification of PAD among patients presenting with DFUs. These strategies may significantly reduce leg amputation rates with only modest increases in cost.

Evaluation for Blunt Cerebrovascular Injury: Review of the Literature and a Cost-Effectiveness Analysis.

BACKGROUND AND PURPOSE: Evaluation for blunt cerebrovascular injury has generated immense controversy with wide variations in recommendations regarding the need for evaluation and the optimal imaging technique. We review the literature and determine the most cost-effective strategy for evaluating blunt cerebrovascular injury in trauma patients. MATERIALS AND METHODS: A comprehensive literature review was performed with data extracted to create a decision-tree analysis for 5 different strategies: anticoagulation for high-risk (based on the Denver screening criteria) patients, selective DSA or CTA (only high-risk patients), and DSA or CTA for all trauma patients. The economic evaluation was based on a health care payer perspective during a 1-year horizon. Statistical analyses were performed. The cost-effectiveness was compared through 2 main indicators: the incremental cost-effectiveness ratio and net monetary benefit. RESULTS: Selective anticoagulation in high-risk patients was shown to be the most cost-effective strategy, with the lowest cost and greatest effectiveness (an average cost of $21.08 and average quality-adjusted life year of 0.7231). Selective CTA has comparable utility and only a slightly higher cost (an average cost of $48.84 and average quality-adjusted life year of 0.7229). DSA, whether performed selectively or for all patients, was not optimal from both the cost and utility perspectives. Sensitivity analyses demonstrated these results to be robust for a wide range of parameter values. CONCLUSIONS: Selective CTA in high-risk patients is the optimal and cost-effective imaging strategy. It remains the dominant strategy over DSA, even assuming a low CTA sensitivity and irrespective of the proportion of patients at high-risk and the incidence of blunt cerebrovascular injury in high-risk patients.

The Utility of Dual-Energy Computed Tomographic Angiography for the Evaluation of Brain Aneurysms After Surgical Clipping: A Prospective Study.

OBJECTIVE: The purpose of this prospective study was to compare a novel dual-energy computed tomographic angiography (DECTA) method for postoperative assessment of clipped brain aneurysms to detect aneurysm remnants and parent artery patency, with catheter-based digital subtraction angiography (DSA). METHODS: Patients who underwent microsurgical cerebral aneurysm repair were prospectively evaluated after surgery by both DECTA and conventional DSA. CTA was performed using a novel dual-energy method with single source and fast kilovoltage switching (Gemstone Spectral Imaging [GSI]). DSA was performed using biplanar cerebral angiography. An experienced neuroradiologist and a neurosurgeon, both blinded to the original radiologic results, reviewed the images. RESULTS: On DSA, 8 of 15 aneurysms (53%) had a remnant after clipping. All of these remnants were <2 mm except for 1. The only residual aneurysm >2 mm was clearly detected by GSI CTA. Of those 7 DSA-confirmed <2-mm remnants, 5 were detected by GSI CTA. Metal artifacts compromised the image quality in 2 patients. The sensitivity and specificity of GSI CTA for remnant aneurysm <2-mm detection in single clip-treated patients were 100%. In all patients, these were 71.4 % and 100%, respectively. GSI CTA was 100% sensitive and 77% specific to detect parent vessel compromise, with associated positive and negative predictive values of 60% and 100%, respectively. CONCLUSIONS: DECTA is a promising noninvasive alternative to conventional catheter-based angiography for identification of aneurysm remnants and assessment of adjacent arteries after surgical clipping of brain aneurysms treated by 2 or fewer clips. It allows for a more rapid image acquisition than DSA, is more cost effective, and is widely available at clinical centers.

Cost-effectiveness of angiographic imaging in isolated perimesencephalic subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The purpose of this study is to perform a comprehensive cost-effectiveness analysis of all possible permutations of computed tomographic angiography (CTA) and digital subtraction angiography imaging strategies for both initial diagnosis and follow-up imaging in patients with perimesencephalic subarachnoid hemorrhage on noncontrast CT. METHODS: Each possible imaging strategy was evaluated in a decision tree created with TreeAge Pro Suite 2014, with parameters derived from a meta-analysis of 40 studies and literature values. Base case and sensitivity analyses were performed to assess the cost-effectiveness of each strategy. A Monte Carlo simulation was conducted with distributional variables to evaluate the robustness of the optimal strategy. RESULTS: The base case scenario showed performing initial CTA with no follow-up angiographic studies in patients with perimesencephalic subarachnoid hemorrhage to be the most cost-effective strategy ($5422/quality adjusted life year). Using a willingness-to-pay threshold of $50 000/quality adjusted life year, the most cost-effective strategy based on net monetary benefit is CTA with no follow-up when the sensitivity of initial CTA is >97.9%, and CTA with CTA follow-up otherwise. The Monte Carlo simulation reported CTA with no follow-up to be the optimal strategy at willingness-to-pay of $50 000 in 99.99% of the iterations. Digital subtraction angiography, whether at initial diagnosis or as part of follow-up imaging, is never the optimal strategy in our model. CONCLUSIONS: CTA without follow-up imaging is the optimal strategy for evaluation of patients with perimesencephalic subarachnoid hemorrhage when modern CT scanners and a strict definition of perimesencephalic subarachnoid hemorrhage are used. Digital subtraction angiography and follow-up imaging are not optimal as they carry complications and associated costs.

Safety, efficacy, and cost of intraoperative indocyanine green angiography compared to intraoperative catheter angiography in cerebral aneurysm surgery.

Intraoperative angiography in cerebrovascular neurosurgery can drive the repositioning or addition of aneurysm clips. Our institution has switched from a strategy of intraoperative digital subtraction angiography (DSA) universally, to a strategy of indocyanine green (ICG) videoangiography with DSA on an as-needed basis. We retrospectively evaluated whether the rates of perioperative stroke, unexpected postoperative aneurysm residual, or parent vessel stenosis differed in 100 patients from each era (2002, "DSA era"; 2007, "ICG era"). The clip repositioning rate for neck residual or parent vessel stenosis did not differ significantly between the two eras. There were no differences in the rate of perioperative stroke or rate of false-negative studies. The per-patient cost of intraoperative imaging within the DSA era was significantly higher than in the ICG era. The replacement of routine intraoperative DSA with ICG videoangiography and selective intraoperative DSA in cerebrovascular aneurysm surgery is safe and effective.

The costs and effects of contrast-enhanced magnetic resonance angiography and digital substraction angiography on quality of life in patients with peripheral arterial disease.

BACKGROUND: Contrast-enhanced magnetic resonance angiography (MRA) and intra-arterial digital subtraction angiography (DSA) both have a high diagnostic performance in the imaging of peripheral arterial occlusive disease (PAOD). However, little is known about the effects of initial, preoperative imaging using MRA or DSA on quality of life (QoL) in relation to costs (cost-utility). PURPOSE: To compare cost-utility of treatment strategies using either MRA or DSA as the principal imaging tool, related to QoL, in patients with PAOD. MATERIAL AND METHODS: In a prospective subgroup analysis of patients randomized between MRA and DSA (n = 79) for preoperative imaging, QoL questionnaires (SF-36) were obtained at randomization and at 4-month follow-up. Cost-effectiveness from hospital perspective was subsequently compared between groups and the difference in gained or lost QoL per € spent assessed using bootstrap analysis. RESULTS: No difference in quality of life was found. A treatment trajectory employing MRA as the principal imaging modality was almost 20% cheaper, leading to a better cost-utility ratio in favor of MRA. CONCLUSION: A treatment plan for peripheral arterial occlusive disease employing MRA versus DSA as the principal imaging modality yields a better cost/QoL ratio for MRA.

Cost-effectiveness of digital subtraction angiography in the setting of computed tomographic angiography negative subarachnoid hemorrhage.

BACKGROUND: Recent studies have documented the high sensitivity of computed tomography angiography (CTA) in detecting a ruptured aneurysm in the presence of acute subarachnoid hemorrhage (SAH). The practice of digital subtraction angiography (DSA) when CTA does not reveal an aneurysm has thus been called into question. OBJECTIVE: We examined this dilemma from a cost-effectiveness perspective by using current decision analysis techniques. METHODS: A decision tree was created with the use of TreeAge Pro Suite 2012; in 1 arm, a CTA-negative SAH was followed up with DSA; in the other arm, patients were observed without further imaging. Based on literature review, costs and utilities were assigned to each potential outcome. Base-case and sensitivity analyses were performed to determine the cost-effectiveness of each strategy. A Monte Carlo simulation was then conducted by sampling each variable over a plausible distribution to evaluate the robustness of the model. RESULTS: With the use of a negative predictive value of 95.7% for CTA, observation was found to be the most cost-effective strategy ($6737/Quality Adjusted Life Year [QALY] vs $8460/QALY) in the base-case analysis. One-way sensitivity analysis demonstrated that DSA became the more cost-effective option if the negative predictive value of CTA fell below 93.72%. The Monte Carlo simulation produced an incremental cost-effectiveness ratio of $83 083/QALY. At the conventional willingness-to-pay threshold of $50 000/QALY, observation was the more cost-effective strategy in 83.6% of simulations. CONCLUSION: The decision to perform a DSA in CTA-negative SAH depends strongly on the sensitivity of CTA, and therefore must be evaluated at each center treating these types of patients. Given the high sensitivity of CTA reported in the current literature, performing DSA on all patients with CTA negative SAH may not be cost-effective at every institution.

Evaluating the use and utility of noninvasive angiography in diagnosing traumatic blunt cerebrovascular injury.

BACKGROUND: Digital subtraction angiography (DSA) is the gold standard for radiographic diagnosis of blunt cerebrovascular injury (BCVI), but use of computed tomography angiography (CTA) and magnetic resonance angiography (MRA) has increased dramatically in BCVI screening. This study explores the utility, effectiveness, and cost of noninvasive CTA and MRA screening for BCVI. METHODS: Medical records of 2,025 consecutive adults evaluated for acute blunt neck trauma and BCVI were reviewed retrospectively. The incidence of BCVI, level(s) of cervical injury, involvement of foramina transversaria and internal carotid canals, presence of bony dislocation or subluxation, and subsequent treatment received were assessed. Asymptomatic patients were analyzed based on fracture and injury patterns. The cost effectiveness of CTA compared with DSA and the effects of CTA sensitivity and screening yield were determined. RESULTS: Of reviewed patients, 196 received CTA or MRA. Thirty-eight patients (19.4%) were diagnosed with BCVI. Screening yield in patients symptomatic at presentation was 48.8%. Large-vessel internal carotid, vertebral, anterior spinal, and basilar artery occlusion were associated with a positive screen, as were concurrent stroke and spinal cord injury (p < 0.01). Of patients with injuries found with noninvasive imaging, 50.0% of BCVI involved C1-3 fracture, 34.2% involved subluxation, and 65.8% involved foramina transversaria. In both symptomatic and asymptomatic patients, CTA screening was more cost effective than DSA. CONCLUSION: Noninvasive imaging is a safe, accurate, and cost-effective tool for BCVI screening. Symptomatic presentation was the best predictor of BCVI. Significant cost savings were realized using CTA rather than DSA, with similar effectiveness and patient outcomes. LEVEL OF EVIDENCE: Diagnostic study, level III; economic analysis, level IV.

Cost-effectiveness of magnetic resonance angiography versus intra-arterial digital subtraction angiography to follow-up patients with coiled intracranial aneurysms.

BACKGROUND AND PURPOSE: To follow up patients with coiled intracranial aneurysms, magnetic resonance angiography (MRA) is a promising noninvasive alternative to current standard intra-arterial digital subtraction angiography (IA-DSA). MRA test results do not always concord with those of IA-DSA, and the impact of discrepancies on health benefits and costs is unknown. We evaluated the cost-effectiveness of follow-up with MRA vs IA-DSA to assess whether in this setting MRA may replace IA-DSA. METHODS: We studied aneurysm occlusion on MRA in addition to follow-up IA-DSA in 310 patients with 341 coiled intracranial aneurysms. The observed sensitivity (82%) and specificity (89%) of MRA for detection of reopening with IA-DSA as a reference were used as input for a Markov decision-analytic model. Other determinants were derived from the literature. We compared life expectancy, quality-adjusted life-years (QALY), costs, and expected number of events for the two strategies. RESULTS: Follow-up with MRA yielded similar life expectancy (MRA, 26.66 years; IA-DSA, 26.63 years; difference, 0.03 years; 95% CI, -0.17-0.23) and QALY (MRA, 10.96; IA-DSA, 10.95; difference, 0.01 QALY; 95% CI, -0.05-0.08) at lower costs (MRA, $7003; IA-DSA, $8241 per patient; difference, -$1238; 95% CI, -2617--36). The expected number of events was comparable except for complications from IA-DSA. CONCLUSIONS: MRA provided equivalent health benefits as IA-DSA and was cost-saving. MRA dominates and should replace routine IA-DSA to follow-up patients with coiled aneurysms.

Cost impact of diagnostic imaging for lower extremity peripheral vascular occlusive disease.

OBJECTIVE: The evaluation of peripheral vascular disease in the primary care setting is routinely performed by contrast-enhanced magnetic resonance angiography (CE-MRA) and digital subtraction angiography (DSA). However, limited data are available on the relative costs and clinical outcomes following these diagnostic procedures. The objective of this study is to assess and compare costs associated with diagnostic imaging in peripheral vascular occlusive disease (PAOD). METHODS: US veterans (n = 19,209) with CE-MRA or DSA for the assessment of PAOD from fiscal year (FY) 1999 to FY 2004. Main outcome measure(s) using the Department of Veterans Affairs' (VA) costing algorithms, cost, and log-cost of interventions (e.g., revascularization, stent, angioplasty), amputations or mortality rates within 30/90 days and 1 year of DSA or CE-MRA were compared, and adjusted for patient characteristics and disease severity using multivariate regression. Imaging modality selection bias was evaluated with propensity score, instrumental variables, and Heckman methods using untransformed costs and log-costs with smearing retransformation. RESULTS: Initial CE-MRA imaging was significantly more likely among patients with prior renal disease or bypass surgery [odds ratio (OR) > 2; P < 0.001], and less likely among patients with prior amputation, peripheral vascular disease (PVD), claudication, or other cardiovascular disease (OR < 0.7; P < 0.001). After adjusting for endogenous choice of initial imaging modality, 30-day treatment costs were US$3500-$4300 lower (P < 0.001) for patients with initial CE-MRA. Eighty-two percent of DSA imaging patients had no additional procedures or events within 30 days, and 65% at 90 days. Less than 3.2% (3.6%) of patients had any repeat imaging within 30 (90) days of initial imaging. CONCLUSIONS: Relative to DSA, CE-MRA imaging was associated with substantial treatment episode savings, beyond the US$950 direct savings in imaging cost per procedure. Substituting CE-MRA for DSA among those not planning or requiring any follow-up procedures within 30 days, could have reduced outpatient imaging costs by up to 55%, and reduced VA system costs by US$13.2 million over the six-year period.

A comparison between willingness to pay and willingness to give up time.

We compared the willingness-to-pay and willingness to give up time methods to assess preferences for digital subtraction angiography (DSA), computed tomography angiography (CTA) and magnetic resonance angiography (MRA). Respondents were hypertensive patients suspected of having renal artery stenosis. Data were gathered using telephone interviews. Both the willingness-to-pay and willingness to give up time methods revealed that patients preferred CTA to MRA in order to avoid DSA. The agreement between willingness-to-pay and willingness to give up time responses was high (kappa 0.65-0.85). The willingness-to-pay method yielded relatively more protest answers (12%) as compared to willingness to give up time (2%). So, our results provided evidence for the comparability of willingness to pay and willingness to give up time. The high percentage of protest answers on the willingness-to-pay questions raises questions with respect to the application of the willingness-to-pay method in a broad decision-making context. On the other hand, the strength of willingness-to-pay is that the method directly arrives at a monetary measure well founded in economic theory, whereas the willingness to give up time method requires conversion to monetary units.

Sixteen-row multislice computerized tomography angiography in the postoperative evaluation of patients with intracranial aneurysms.

The goal of this study was to assess the diagnostic accuracy of 16-row multislice computed tomography angiography (CTA) compared with digital subtraction angiography (DSA) in the detection of aneurysm remnants and arterial patency after clipping of intracranial aneurysms. Thirty-seven consecutive patients with 40 clipped aneurysms (39 of which had ruptured) were studied with the aid of postoperative CTA and DSA. CTA was performed with a 16-row multislice CT scanner by using collimation of 0.75 mm. Two neuroradiologists evaluated the image quality of CTA and the presence of the residual aneurysms with a 5-point rating scale. DSA was considered a reference standard. Two aneurysms with incomplete closure were identified by the 16-slice CTA reconstructions. With 16-slice CTA, there were no false-positive results of an aneurysm with incomplete closure in any patient. Arterial patency could be reliably evaluated close to the clip. The sensitivity, specificity, and accuracy of 16-slice CTA for aneurysm occlusion and arterial patency were 100%[97.5% confidence interval (CI): 15.8 - 100%], 100% (97.5% CI: 90.7 - 100%) and 100% (97.5% CI: 91.2 - 100%), respectively. The positive and negative predictive values were 100 and 100%, respectively. The mean duration of the examination was 12 min for CTA and 40 min for DSA (p < 0.05). Sixteen-slice CTA was highly cost effective (p < 0.05). Sixteen-slice CTA is a valuable non-invasive diagnostic modality for the assessment of aneurysm remnants and arterial patency in patients after aneurysm clipping. Its high sensitivity and low cost warrant its use for postoperative routine control examinations following clip placement on an aneurysm.

Renal artery stenosis: cost-effectiveness of diagnosis and treatment.

PURPOSE: To use a decision analytic model to determine the cost-effectiveness of performing diagnostic digital subtraction angiography (DSA), computed tomographic (CT) angiography, or magnetic resonance (MR) angiography or proceeding immediately to tentative percutaneous revascularization in patients suspected of having renovascular hypertension. MATERIALS AND METHODS: With use of a Markov-Monte Carlo decision model, cost-effectiveness analysis was performed from a societal perspective. Data were derived from the Renal Artery Diagnostic Imaging Study in Hypertension and from published literature. The base-case analyses were used to evaluate a 50-year-old patient with a diastolic blood pressure higher than 95 mm Hg and one or more clinical clues suggestive of renovascular hypertension. Outcome measures were quality-adjusted life-year (QALY), lifetime costs, and incremental cost-effectiveness. RESULTS: For a 50-year-old male patient, immediate tentative revascularization was the least costly (euro54 415) and most effective (12.265 QALYs) strategy. For the other strategies, costs and QALYs, respectively, were euro55 570 and 12.195 for DSA, euro55 191 and 12.163 for CT angiography, and euro56 890 and 12.088 for MR angiography. For a 50-year-old female patient, costs and QALYs, respectively, were euro66 731 and 13.731 for MR angiography, euro63 970 and 13.749 for CT angiography, and euro63 079 and 13.902 for DSA. Immediate tentative revascularization yielded more QALYs (13.937) and was more costly (euro63 329) than DSA. The incremental cost-effectiveness ratio was euro7143 per QALY. As the prior probability increased, use of a more invasive diagnostic imaging strategy became justified. Also, the sensitivities of CT angiography and MR angiography and the costs of DSA influenced the results. CONCLUSION: Given currently accepted incremental cost-effectiveness ratios, immediate tentative percutaneous revascularization is a cost-effective strategy for the diagnosis of renal artery stenosis. Management decisions should be conditional on the prior probability.

Angiografia: segurança x economia / Angiography: safety x economy

OBJETIVO: Avaliar a segurança, eficiência e custos do exame angiofluoresceinográfico utilizando menor dosagem de contraste e aparelho digital com máquina de fotocópia a laser. MÉTODOS: Estudo prospectivo e comparativo entre um grupo de 70 pacientes que foi submetido à avaliação angiográfica com retinógrafo convencional, injetando-se 5 ml de fluoresceína sódica a 10 por cento (grupo controle), e um grupo de 70 pacientes que foi submetido à avaliação angiográfica com retinógrafo digital injetando-se 2 ml de fluoresceína a 10 por cento (grupo estudo). Pressão arterial, freqüência cardíaca e oximetria foram avaliadas antes e após a injeção de contraste. Reações orgânicas, relacionadas ao exame, foram notificadas. A qualidade das fotografias e os custos foram comparados entre as duas técnicas. RESULTADOS: Observou-se que os pacientes do grupo controle apresentaram maior aumento da pressão arterial sistólica e diastólica. Freqüência cardíaca, oximetria e reações adversas não demonstraram diferenças estatisticamente significativas entre os dois grupos. Quanto à qualidade das fotografias foi notado melhor desempenho no grupo controle. Quanto aos custos observou-se que o exame realizado no grupo estudo proporcionou economia de aproximadamente 54,8 por cento por exame em relação ao grupo controle. CONCLUSÃO: A realização do exame com menor dosagem de fluoresceína, utilizando equipamento digital com máquina de fotocópia a laser, proporcionou maior estabilidade da pressão arterial sistólica e diastólica, porém não exerceu influência sobre a freqüência cardíaca, oximetria e reações adversas como náusea, vômito, síncope e urticária. A qualidade das fotografias pode ser considerada inferior, porém possibilitou a realização de diagnóstico e orientação terapêutica para quem executou o exame. Economicamente apresentou geração de lucro de 66,26 por cento contra 25,81 por cento do equipamento convencional.

PURPOSE: To evaluate the safety, effectiveness, and cost of angiofluoresceinographic examination by using both the least amount of dye as well as digital equipment along with a laser photocopier. METHODS: Prospective and comparative study carried out in a group of 70 patients, who underwent an angiographic evaluation with a conventional retinographer injecting 5 ml sodium fluorescein at 10 percent (control group) as well as a group of 70 patients who underwent an angiographic evaluation with a digital retinographer injecting 2 ml fluorescein at 10 percent (study group). Arterial pressure, heart rate and oximetry were assessed prior to and after the dye injection. Organic reactions related to the examination were reported. Photograph quality as well as cost between the two techniques were compared. RESULTS: Control group patients showed a greater increase in systolic and diastolic arterial pressure. Heart rate, oximetry measurement and adverse reactions did not show any significant statistical differences between both groups. As for the quality of photographs, a better performance was noticed in the control group. As for the cost, the examination carried out in the study group required lower cost and thus saved around 54.8 percent per examination in relation to the control group. CONCLUSION: The examination carried out with a lower dose of fluorescein using digital equipment along with a laser photocopier provided greater stability in the systolic and diastolic arterial pressure. However, it did not have any influence on heart rate, oximetry or adverse reactions such as nausea, vomiting, syncope and rashes. The quality of photographs was poor although they enabled diagnosis as well as therapy follow-up for those who carried out the examination. Moreover, economically the above procedure represented a gain of 66.26 percent, against 25.81 percent in relation to the conventional equipment.

MR angiography versus intra-arterial digital subtraction angiography of the lower extremities: activity-based cost analysis.

PURPOSE: The aim of this study was to analyse the costs pertaining to the radiology department of magnetic resonance angiography (MRA) and intra-arterial digital subtraction angiography (DSA) in the evaluation of arterial disease of the lower limbs. MATERIALS AND METHODS: The differential cost of the two procedures, i.e. the sum of equipment costs (amortisation and service contract), variable costs (supplies and related services) and personnel costs (radiologist, radiographer and nurse) was determined. The common cost (auxiliary personnel and indirect internal costs) was also calculated. Finally, the full cost of the two procedures was obtained (sum of differential and common costs). RESULTS: The differential cost of MRA was 186.14 euro (equipment costs: 50.80 euro, variable costs: 75.04 euro, personnel costs: 60.30 euro) while the differential cost of intra-arterial DSA was 238.18 euro (equipment costs: 57.60 euro, variable costs: 90.13 euro, staff costs: 90.45 euro). The estimated common cost was 5.62 euro. Therefore, the full cost of MRA was 191.76 euro and the full cost of intra-arterial DSA was 243.80 euro (27.1% higher). DISCUSSION AND CONCLUSIONS: Intra-arterial DSA costs more than MRA, mainly because of the higher costs of supplies used during the procedure and higher personnel costs (as a result of the longer duration of intra-arterial DSA). It should be noted that our evaluation considers costs pertaining to the radiology department only. It is evident that an economic analysis considering hospital costs as well would result in much higher costs for DSA if post-procedure hospitalisation is required. Our results cannot be simply exported to other radiology departments since they refer to the technology and organisation adopted in our department. However, our cost analysis model can be easily applied to other environments. MRA provides good diagnostic accuracy in the evaluation of arteries of the lower extremities, and its biological cost is far lower than that of intra-arterial DSA (MRA is noninvasive, it does not use ionising radiation, and the contrast medium is safe). Its lower cost is another argument in favour of the use of MRA instead of intra-arterial DSA in the evaluation of lower-extremity arterial disease.

Cost analysis of procedures related to the management of renal artery stenosis from various perspectives.

To determine the costs associated with the diagnostic work-up and percutaneous revascularization of renal artery stenosis from various perspectives. A prospective multicenter comparative study was conducted between 1998 and 2001. A total of 402 hypertensive patients with suspected renal artery stenosis were included. Costs were assessed of computed tomography angiography (CTA), magnetic resonance angiography (MRA), digital subtraction angiography (DSA), and percutaneous revascularization. From the societal perspective, DSA was the most costly (euro 1,721) and CTA the least costly diagnostic technique (euro 424). CTA was the least costly imaging procedure irrespective of the perspective used. The societal costs associated with percutaneous renal artery revascularization ranged from euro 2,680 to euro 6,172. Overall the radiology department incurred the largest proportion of the total societal costs. For the management of renal artery stenosis, performing the analysis from different perspectives leads to the same conclusion concerning the least costly diagnostic imaging and revascularization procedure.