Editor's Choice - A Comparison of Computed Tomography Angiography and Colour Duplex Ultrasound Surveillance Post Infrarenal Endovascular Aortic Aneurysm Repair: Financial Implications and Impact of Different International Surveillance Guidelines.

OBJECTIVE: Use of colour duplex ultrasound (CDUS) and computed tomography angiography (CTA) for infrarenal endovascular aortic aneurysm repair (EVAR) surveillance differs in internationally published guidelines. This study aimed firstly to compare CDUS detection of significant sac abnormalities with CTA. Secondly, a sensitivity analysis was conducted to compare financial estimates of the, predominantly CDUS based, local and Society of Vascular Surgery (SVS) protocols, the risk stratified European Society of Vascular Surgery (ESVS) protocol, and the CTA based National Institute of Health and Care Excellence (NICE) protocol. METHODS: Agreement between CDUS and CTA was assessed for detection of significant sac abnormalities. Surveillance protocols were extrapolated from published guidelines and applied to infrarenal EVAR patients active on local surveillance at a large, single centre. Surveillance intensity was dependent on presence of endoleak and subsequent risk of treatment failure in accordance with surveillance recommendations. Estimates for each surveillance protocol were inclusive of a range of published incidences of endoleak, contrast associated acute kidney injury (AKI), and excess hospital bed days, and estimated for a hypothetical five year surveillance period. RESULTS: The kappa coefficient between CDUS and CTA for detecting sac abnormalities was 0.68. Maximum five year surveillance cost estimates for the 289 active EVAR patients were £272 359 for SVS, £230 708 for ESVS, £643 802 for NICE, and £266 777 for local protocols, or £1 270, £1 076, £3 003, and £1 244 per patient. Differences in endoleak incidence accounted for a 1.1 to 1.4 fold increase in costs. AKI incidence accounted for a 3.3 to 6.2 fold increase in costs. CONCLUSION: A combined CTA and CDUS EVAR surveillance protocol, with CTA reserved for early seal assessment and confirmatory purposes, provides an economical approach without compromising detection of sac abnormalities. AKI, as opposed to direct imaging costs, accounted for the largest differences in surveillance cost estimates.

Cost-effectiveness of contrast-enhanced ultrasound for the detection of endovascular aneurysm repair-related endoleaks requiring treatment.

OBJECTIVE: Follow-up after endovascular aneurysm repair is necessary to detect potentially life-threatening complications such as endoleaks. Computed tomography angiography (CTA) or magnetic resonance angiography (MRA) is often used as standard of care for follow-up. Contrast-enhanced ultrasound (CEUS) has been shown to be a viable and fast real-time nonionizing imaging modality with equivalent diagnostic accuracy while also being superior to color Doppler ultrasound. The aim of this cost-utility analysis was to evaluate the cost-effectiveness of this imaging method in comparison to others for the evaluation of endoleaks requiring treatment. METHODS: A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with CTA, MRA, CEUS, and color Doppler ultrasound. Model input parameters were obtained from recent literature. The applied sensitivity and specificity values amounted to 90.5% and 100.0% for CTA, 96.0% and 100.0% for MRA, 94.0% and 95.0% for CEUS, and 82.0% and 93.0% for color Doppler ultrasound. Probabilistic and deterministic sensitivity analysis was performed to estimate uncertainty of model results. To evaluate cost-effectiveness, incremental cost-effectiveness ratios were reported as a measure representing the economic value of a strategy compared with an alternative. The willingness to pay was set to $100,000/QALY. RESULTS: In the base-case scenario for a willingness to pay of $100,000 per QALY, CEUS was the most cost-effective of the four diagnostic strategies with estimated costs of $17,383 and effectiveness of 9.770 QALYs. CTA was estimated to result in lifetime costs of $17,679 with an expected effectiveness of 9.768 QALYs, whereas color Doppler ultrasound showed expected costs of $17,287 with 9.763 QALYs. Expected costs and effectiveness of MRA amounted to $17,945 and 9.771 QALYs each. Base-case estimates of the incremental cost-effectiveness ratios for CEUS vs color Doppler ultrasound equaled $14,173.52/QALY. CONCLUSIONS: CEUS is a cost-effective imaging method for the evaluation of therapy-requiring endoleaks in endovascular aneurysm repair surveillance.

Should We Use Contrast-Enhanced Ultrasound (CEUS) for the Characterization of Nonpalpable Testicular Lesions? An Analysis from a Cost-Effectiveness Perspective.

PURPOSE: Accurate characterization of testicular lesions is crucial to allow for correct treatment of malignant tumors and to avoid unnecessary procedures in benign ones. In recent years, contrast-enhanced ultrasound (CEUS) proved to be superior in specifying the dignity of small, nonpalpable testicular lesions (< 1.5 cm) compared to native B-mode and color Doppler ultrasound which were previously regarded as the primary imaging method. However, the cost-effectiveness of CEUS has not been evaluated yet. The aim of this study was to analyze the cost-effectiveness of CEUS as compared to unenhanced ultrasound for the characterization of nonpalpable testicular lesions. METHODS: A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with unenhanced ultrasound and CEUS. Model input parameters were obtained from recent literature. Deterministic sensitivity analysis of diagnostic parameters and costs was performed. Also, probabilistic sensitivity analysis using Monte-Carlo Modelling was applied. The willingness-to-pay (WTP) was set to $100 000/QALY. RESULTS: In the base-case scenario, unenhanced ultrasound resulted in total costs of $5113.14 and an expected effectiveness of 8.29 QALYs, whereas CEUS resulted in total costs of $4397.77 with 8.35 QALYs. Therefore, the unenhanced ultrasound strategy was dominated by CEUS in the base-case scenario. Sensitivity analysis showed CEUS to be the cost-effective alternative along a broad range of costs. CONCLUSION: Contrast-enhanced ultrasound is a cost-effective imaging method for the characterization of nonpalpable testicular lesions.

Preoperative ultrasound improves patency and cost effectiveness in arteriovenous fistula surgery.

OBJECTIVE: We aimed to compare routine preoperative color-coded duplex ultrasound (DUS) to clinical examination (CE) alone in surgery for arteriovenous fistula (AVF) with special emphasis on long-term outcomes and cost effectiveness. METHODS: All patients undergoing an AVF formation or revision between January 1, 2011, and December 31, 2016, at our tertiary referral center were subject to analysis. Routine DUS was performed in 114 patients and CE alone in 217 patients. Primary and secondary patency, the need for revision or reintervention to obtain patency, and individual as well as overall costs were analyzed. RESULTS: Primary patency rate was higher in AVF after DUS compared with CE alone at 62% vs 26% (P < .05), respectively. Patients receiving DUS had significantly lower rates of revision and revisions per patient when compared with CE (25.4% vs 59.4% [P < .0001]; 0.36 ± 0.71 vs 1.06 ± 1.55 [P < .0001], respectively). Costs per patient were significantly lower in the DUS group compared with CE at 4074€ vs 6078€ (P < .0001). CONCLUSIONS: We were able to show that patients receiving preoperative DUS showed higher patency rates and needed fewer revisions. Standard preoperative ultrasound examination is an easy tool to improve outcomes and cost effectiveness in AVF surgery.

Color Doppler and spectral Doppler ultrasound detection of active sacroiliitis in spondyloarthritis compared to physical examination as gold standard.

Sacroiliac joint (SIJ) involvement is a distinctive feature of spondyloarthritis (SpA). The main objective of this study was to assess the validity of color Doppler ultrasound (CDUS) in SIJ. This was a cross-sectional, blinded, case-control study of 108 cases divided into three groups: (a) 53 SpA patients with inflammatory back pain (IBP); (b) 28 SpA patients with no IBP; and (c) 27 healthy mechanical lumbar pain subjects. Physical examinations of the SIJs were assessed as positive or negative in each SIJ and were used as the gold standard. SIJs were examined with CDUS and spectral Doppler, and the SIJs were assessed as positive when both color Doppler and the resistance index (RI) were less than the cut-off point within the SIJs area. A total of 108 cases (53 female; mean age 36 ± 10 years old) were studied. The physical examination of the SIJs was positive in 38 patients (59 SIJs). Ultrasound detected Doppler signal within the SIJs in 37 cases (58 SIJs): 33 of them had symptomatic SpA (52 SIJs), 3 of them had asymptomatic SpA (5 SIJs), and 1 was a healthy control (1 SIJ). The accuracy of CDUS, when compared to physical SIJ examination, at the patient level in the overall group had a sensitivity of 70.3%, a specificity of 85.7%, a positive likelihood ratio of 4.9, and a negative likelihood ratio of 0.36. For the spectral Doppler RI, with an optimal cut-off point ≤0.75, the sensitivity was 76.2%, and the specificity was 77.8%. CDUS of SIJs seems to be a feasible and valid method for detecting active inflammation in patients with SpA.

Cost-effective initial assessment strategies for thyroid nodules in iodine-adequate areas.

OBJECTIVE: In the initial assessment of thyroid nodules, thyrotropin (TSH) has very low sensitivity for assessing functional thyroid nodules (FTNs). The false negativity in FTNs and the false positivity in non-FTNs misinterpreted by TSH will raise unnecessary assessment costs. Therefore, the aim of this study is to explore the values of the TSH and color flow Doppler sonography (CFDS) combined strategies in reducing the unnecessary assessment costs. METHODS: 2383 patients with thyroid nodules were retrospectively analyzed, including 107 FTNs and 2276 non-FTNs. Four strategies including TSH, CFDS, Combination 1 (TSH+/CFDS+, TSH+/CFDS-, and TSH-/CFDS+ defined as positive; TSH-/CFDS- defined as negative) and Combination 2 (TSH+/CFDS+ defined as positive; TSH+/CFDS-, TSH-/CFDS+, and TSH-/CFDS- defined as negative) were separately used for initial assessment. The four strategies were compared using the testing cost ratio of fine-needle aspiration (FNA) to thyroid scintigraphy (TS) (marked as CFNA/TS) as main outcome measure. RESULTS: Compared with TSH, Combination 1 prevented 15.89 % of FTNs from unnecessary FNA, but increased the number of non-FTNs subjected to unnecessary 99mTc-TS by 9.31 %. Combination 2 prevented 5.32 % of non-FTNs from unnecessary TS, but increased the number of FTNs subjected to unnecessary FNA by 18.69 %. When CFNA/TS was <6.05, the lowest total cost was found in Combination 2. The TSH and Combination 1 were optimal at 6.05 ≤ CFNA/TS ≤ 12.47 and CFNA/TS > 12.47, respectively. CONCLUSIONS: The combined strategies can be used to supplement TSH in the initial assessment of thyroid nodules in iodine-adequate areas, depending on the testing costs of FNA and TS.

Pelvic inflammatory disease: identifying research gaps--proceedings of a workshop sponsored by Department of Health and Human Services/National Institutes of Health/National Institute of Allergy and Infectious Diseases, November 3-4, 2011.

In November 2011, the National Institutes of Health convened a workshop of basic researchers, epidemiologists, and clinical experts in pelvic inflammatory disease to identify research gaps hindering advances in diagnosis, treatment, and prevention. This article summarizes the presentations, discussions, and conclusions of this group and highlights significant controversies that reveal aspects of pelvic inflammatory disease research that would most greatly benefit from the application of newer molecular, immunologic, and radiologic techniques. Multiple limitations to performing new clinical trials exist; however, emerging data from ongoing clinical trials will add to the current body of knowledge regarding prevention and treatment strategies. In addition, use of established health care databases could serve as a valuable tool for performance of unbiased epidemiologic outcome studies.

Use of colour duplex ultrasound as a first line surveillance tool following EVAR is associated with a reduction in cost without compromising accuracy.

INTRODUCTION: CT scanning remains the postoperative surveillance imaging modality of choice following EVAR. Concerns regarding cost, exposure to ionising radiation and intravenous contrast have led to a search for a less expensive, equally efficacious and safer method of monitoring EVAR patients after endograft deployment. This study evaluated the cost saving obtained if CDUS was employed as a first line surveillance tool following EVAR, as well as comparing the two entities in terms of efficacy. PATIENTS & METHODS: Postoperative surveillance CTs and CDUS scans in the 145 patients who have undergone EVAR from 1st June 2003 to 1st July 2010 were compared for the detection of endoleak and determination of residual sac size. RESULTS: Adopting a protocol where CDUS was employed as the first line surveillance tool following EVAR would result in a reduction in the number of postoperative CTs required in 2010 from 235 to 36. Based on 2010 costings, this would equate to an estimated reduction in expenditure from €117,500 to €34,915 a saving of €82,585. CDUS had a sensitivity of 100% and a specificity of 85% in the detection of endoleaks compared to CT. The positive predictive value was 28% and negative predictive value 100%. The Pearson Coefficient correlation of 0.96 indicates a large degree of correlation between CDUS and CT when measuring residual aneurysm size following EVAR. CONCLUSION: CDUS can replace CT as the first line surveillance tool following EVAR. This is associated with a significant reduction in the cost of surveillance without any loss of imaging accuracy.

A low-cost, durable, combined ultrasound and fluoroscopic phantom for cervical transforaminal injections.

BACKGROUND: This technical report describes a durable, low-cost, anatomically accurate, and easy-to-prepare combined ultrasound (US) and fluoroscopic phantom of the cervical spine. This phantom is meant to augment training in US- and fluoroscopic-guided pain medicine procedures. METHODS: The combined US and fluoroscopic phantom (CUF-P) is prepared from commercially available liquid plastic that is ordinarily used to prepare synthetic fishing lures. The liquid plastic is heated and then poured into a metal canister that houses an anatomical cervical spine model. Drops of dark purple dye are added to make the phantom opaque. After cooling, tubing is attached to the CUF-P to simulate blood vessels. RESULTS: The CUF-P accurately simulates human tissue by imitating both the tactile texture of skin and the haptic resistance of human tissue as the needle is advanced. This phantom contains simulated fluid-filled vertebral arteries that exhibit pulsed flow under color Doppler US. Under fluoroscopic examination, the CUF-P-simulated vertebral arteries also exhibit uptake of contrast dye if mistakenly injected. CONCLUSIONS: The creation of a training phantom allows the pain physician to practice needle positioning technique while simultaneously visualizing both targeted and avoidable vascular structures under US and fluoroscopic guidance. This low-cost CUF-P is easy to prepare and is reusable, making it an attractive alternative to current homemade and commercially available phantom simulators.

Role of ultrasonography in the differential diagnosis of thyrotoxicosis: a noninvasive, cost-effective, and widely available but underutilized diagnostic tool.

OBJECTIVE: To explore the use of ultrasonography as a diagnostic alternative to the traditional "gold standard" imaging study of nuclear scintigraphy in the evaluation of thyrotoxicosis. METHODS: We review the relevant literature and share our own experience to highlight the promising role of ultrasonography in thyrotoxicosis. In addition, we present a diagnostic algorithm suggesting liberal use of ultrasonography in the evaluation of thyrotoxicosis. RESULTS: Ultrasonography has proved effective not only in the differentiation of Graves disease from other types and causes of thyrotoxicosis but also in the detection of subtle thyroid nodules. The latter role is emphasized in light of the recent observation of an increased risk of occurrence of papillary thyroid carcinoma in patients with Graves disease. CONCLUSION: Ultrasonography is a cost-effective, noninvasive, portable, and safe imaging modality in the evaluation of thyrotoxicosis, both for physiologic assessment and for detection of nonpalpable thyroid cancers that may elude identification on physical examination and nuclear imaging studies. Although thyroid scintigraphy remains a standard radiologic study, thyroid ultrasonography can be a practical alternative in many cases and the primary imaging modality in some situations such as during pregnancy and lactation and for evaluation and management of amiodarone-induced thyrotoxicosis.

[Ultrasound for surveillance after endovascular repair of abdominal aortic aneurysm--simple and safe?]. / Welche Nachkontrolle ist bei endovaskulärer Versorgung von abdominellen Aortenaneurysmen empfehlenswert?

In the past, multislice computed tomography angiography (CTA) with arterial and venous phase was recommended as the gold standard in follow-up after endovascular abdominal aneurysm repair (EVAR). Iodine-containing contrast agents and frequent radiation exposure are limitations for use in elderly patients with chronic renal insufficiency. Colour-coded Doppler sonography (CCDS) and, especially, contrast-enhanced ultrasound (CEUS) are non-invasive methods that are time and cost effective. Both provide a reliable alternative to CTA in surveillance after EVAR. CEUS seems to be superior in characterisation of the type of endoleaks and can be established in order to reduce iodine-containing contrast agent and radiation exposure in follow-up. In contrast to CTA scans, CEUS can be offered to patients with chronic renal insufficiency and allows a dynamic examination and perfusion analysis (e. g., in fenestrated and branched stentgrafts). Routine combination with X-ray allows control of stentgraft material and location of the branches.

Deep venous thrombosis in gynecological oncology: incidence and clinical symptoms study.

OBJECTIVE: Cancer patients have increased risks of leg deep venous thrombosis (DVT). We studied the incidence, risk factors and most predictive symptoms of leg DVT in gynecologic oncology patients. STUDY DESIGNS: Gynecologic oncology patients with any leg DVT symptoms were recruited and screened using Doppler sonogram. All hospitalized surgery and non-ambulating patients received thigh-high sequential compression devices (SCDs) without heparin as a prophylactic method against thrombosis. Statistical analysis was done using chi-square or Fisher's exact tests. RESULTS: Out of 1974 patients, 134 complained of lower limb symptoms. Doppler studies found 38 patients with leg DVT. Incidence of leg DVT was 36/853 (4.2%) in patients with cancer and 2/1121 (0.2%) in patients without cancer (odds ratio 2.8 with a diagnosis of cancer). Leg edema, erythema, fever, and warm leg were significant symptoms in diagnosing leg DVT (p<0.01). The cost of finding a leg DVT was $747.54. CONCLUSIONS: Clinical exam is less accurate than Doppler sonogram in diagnosing leg DVT. The incidence of leg DVT using SCD seems to be comparable with other studies. Finally, the cost of identifying leg DVT seems reasonable.

[Imaging of arteries and veins]. / Bildgebung von Arterien und Venen.

For all arteries, which are easily accessible by ultrasound, a colordoppler ultrasound investigation is the first choice. The method is cost effective, precise, without radiation hazard and generates not only morphological, but also useful hemodynamic information. For the investigation of veins (Varicosis and thrombosis) colordoppler ultrasound has almost uniformly replaced phlebography as the method of choice.

The role of imaging in Graves' disease: a cost-effectiveness analysis.

According to many guidelines, scintigraphy remains the first suggested diagnostic procedure in hyperthyroid patients in spite of the widespread availability of ultrasounds. The aim of this study was to evaluate the cost-effectiveness of sonography versus scintigraphy in the management of Graves's disease, and to assess ultrasound features suggesting cancer in detecting thyroid nodules. Among 1470 hyperthyroid patients evaluated in our department from 2002 to 2005, 426 (29%) had Graves' disease: echographic and scintigraphic features were not suggestive of GD in 20/426 (4.8%) and 11/426 (2.6%) patients, respectively (p=0.763), even if one of the two procedures was almost always diagnostic. Ultrasound identified 68/426 (16%) patients with a concomitant solid lesion, while scintigraphy detected only 9/426 (2.1%) "cold" nodules (p<0.001). Thyroid cancer was diagnosed in 30/68 (47.7%) patients. Malignancy presented at ultrasound investigation blurred margins (26.7% versus 15.8%), microcalcifications (33.3% versus 28.9%) and an anteroposterior and transverse diameter ratio>or=1 (73.3% versus 71.1%); more frequently than benign nodules, but this was not statistically significant. The total cost to obtain a diagnosis by ultrasound was euro14645.34 (euro13312.5 for echography+euro1332.84 for scintigraphy in the 29 patients "negative" at echographic evaluation for GD) versus euro19922.71 by scintigraphy (euro19578.96 for scan+euro343.75 for ultrasounds in the 11 patients "negative" at scintigraphy). Our data show no difference in terms of diagnosis between sonography and scintigraphy. Indeed, scintigraphy was less sensitive in detecting nodules (often of malignant nature) than ultrasound, and, moreover, with a consequent increase of the direct cost of nodule management when scintigraphy is the first line procedure. In conclusion, according to our results, we suggest that ultrasounds with color-Doppler evaluation should be performed as first step in all hyperthyroid patients, and that scintigraphic examination should be limited only to the uncommon cases, where physician's observation, laboratory assays and/or ultrasounds are not diagnostic.

Does the adjunct of ecographic contrast medium Levovist improve the detection rate of prostate cancer?

OBJECTIVES: To evaluate whether the adjunct of an ultrasound contrast medium improves the detection rate of prostate cancer. METHOD: In 34 patients, scheduled to undergo a trans-perineal extended prostate biopsy, we carried out a color-Doppler ultrasound (CDU) of the prostate before and after i.v. injection of Levovist, an ultrasound contrast medium. Further bioptic samples were taken in the areas where a marked increase in vascularization was noticed. RESULTS: The overall diagnostic sensitivity, specificity and efficiency were respectively 72.7, 56.2 and 62.9% for transrectal ultrasound (TRUS); 80, 56.2 and 65.3% for CDU and 88.8, 54.5 and 68% for CDU after Levovist injection; 66.5, 72.6 and 65.1% for digito-rectal examination (DRE); 100, 51.4 and 65.4% for total PSA; and 100, 88.8 and 94.3% for PSA free/total. In the 16 patients with prostate carcinoma, the sensitivity of CDU after Levovist was 92.3, 66% for both DRE and TRUS, and 80% for DRE plus TRUS. CONCLUSIONS: Considering the cost and the results obtained (high sensitivity and low specificity), a routine use of Levovist does not seem indicated in patients undergoing prostatic biopsy. An exception may be represented by patients with both negative DRE and TRUS.

Cost-effectiveness of diagnostic imaging work-up and treatment for patients with intermittent claudication in The Netherlands.

OBJECTIVE: to determine the societal cost-effectiveness of various management strategies, including both the diagnostic imaging work-up and treatment, for patients with intermittent claudication in The Netherlands. METHODS: a decision-analytic model was used and included probability and quality of life data available from the literature. A cost-analysis was performed in a university setting in The Netherlands. Imaging work-up options included magnetic resonance angiography (MRA), color-guided duplex ultrasound, or intraarterial digital subtraction angiography (DSA) and treatment options were percutaneous transluminal angioplasty with selective stent placement if feasible or bypass surgery. Management strategies were defined as combinations of imaging work-up and treatment options. A conservative strategy with no imaging work-up and walking exercises was considered as reference. Main outcome measures were quality-adjusted life years (QALYs), lifetime costs (euro), and incremental cost-effectiveness (CE) ratios. The base-case analysis evaluated 60-year-old men with severe unilateral intermittent claudication of at least one year duration. RESULTS: the range in QALYs and costs across management strategies that considered angioplasty as only treatment option was small (maximum difference: 0.0033 QALYs and 451 euros). Similarly, the range was small across management strategies that considered angioplasty if feasible otherwise bypass surgery (maximum difference: 0.0033 QALYs and 280 euros). MRA in combination with angioplasty (6.1487 QALYs and 8556 euros) had a CE ratio of 20,000 euros/QALY relative to the conservative strategy. The most effective strategy was DSA in combination with angioplasty if feasible otherwise bypass surgery (6.2254 QALYs and 18,583 euros) which had a CE ratio of 131,000 euros/QALY relative to MRA in combination with angioplasty. CONCLUSION: the results suggest that the imaging work-up with non-invasive imaging modalities can replace DSA for the work-up of patients with intermittent claudication without a substantial loss in effectiveness and a minimal cost-reduction. Management strategies including angioplasty are cost-effective in the Netherlands but although strategies including bypass surgery are more effective, their incremental costs are very high.

Pretreatment imaging workup for patients with intermittent claudication: a cost-effectiveness analysis.

PURPOSE: To determine the optimal imaging strategy in pretreatment workup of patients with intermittent claudication with use of noninvasive imaging modalities and intraarterial digital subtraction angiography (DSA). MATERIALS AND METHODS: A decision-analytic model that considered test characteristics such as sensitivity, complications induced by the test, implications of missing lesions, and the consequences of overtreating patients, was developed to evaluate the societal cost-effectiveness (CE) of magnetic resonance (MR) angiography, duplex ultrasonography (US), and DSA. Our main outcome measures were quality-adjusted life years (QALYs), lifetime costs (in dollars), and incremental CE ratios. The base-case analysis considered a cohort of 60-year old male patients without a history of coronary artery disease who presented with severe claudication to undergo pretreatment imaging workup. RESULTS: The range in effectiveness and lifetime costs among different diagnostic workup strategies was small (largest difference in effectiveness: 0.025 QALYs; largest difference in lifetime costs: $1,800). If treatment was limited to angioplasty in patients with suitable lesions, MR angiography had an incremental CE ratio of $35,000 per QALY compared with no diagnostic workup, and DSA had an incremental CE ratio of $471,000 per QALY compared with MR angiography. If treatment options included both angioplasty and bypass surgery, DSA had an incremental CE ratio of $179,000 per QALY compared with no diagnostic workup, and MR angiography and duplex US were less effective and more costly. CONCLUSIONS: The differences in costs and effectiveness among diagnostic imaging strategies for patients with intermittent claudication are slight and MR angiography or duplex US can replace DSA without substantial loss in effectiveness and with a slight cost reduction.