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Temporal arteritis (TA) is the most common form of systemic vasculitis. Its diagnosis is based on criteria proposed by the American College of Rheumatology (1990), and its treatment is high-dose corticosteroids. Our objective is to assess the cost of diagnosing TA, and secondarily, cost-effective analysis of different diagnostic strategies (clinical, biopsy, doppler ultrasound) and therapeutic strategies (corticosteroid suspension)., Material and Method: Observational, retrospective study has been carried out on patients with AT (2012-2021). Demographic data, comorbidities, signs and symptoms suggestive of AT were collected. AT was diagnosed with a score ≥ 3 according to American College of Rheumatoloy criteria (ACR-SCORE). The costs of diagnosis and treatment modification were analysed., Results: Seventy-five patients have been included, median age 77 (46-87) years. Headache, temporal pain and jaw claudication were significant for the diagnosis of TA. Patients with a halo on Doppler ultrasound and a positive biopsy have significantly elevated ESR and CRP compared to patients who do not. The cost of the AT diagnosis was 414.7 euros/patient. If we use ACR-SCORE ≥ 3-echodoppler it is 167.2 є/patient (savings 59.6%) and ACR-SCORE ≥ 3-biopsy 339.75 є/patient (savings 18%). If the corticosteroid was removed and a biopsy was performed, 21.6 є/patient (94.7% savings), if the corticosteroid was removed and Doppler ultrasound was performed, 10.6 є/patient (97.4% savings)., Conclusions: Headache, temporary pain and jaw claudication are predictors of AT. Elevated ESR and CRP are predictors of positive biopsy and presence of halo on ultrasound. The uses of ACR-SCORE ≥ 3 with Doppler ultrasound or biopsy, and with corticosteroid suspension, are cost-effective., (Copyright © 2023 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.)

Background Imaging may play an important role in identifying high-risk plaques in patients who have carotid disease and who could benefit from surgical revascularization. We sought to evaluate the cost effectiveness of a decision-making rule based on the ultrasound imaging assessment of plaque echolucency in patients with asymptomatic carotid stenosis. Methods and Results We used a decision-analytic model to project lifetime quality-adjusted life years and costs for 5 stroke prevention strategies: (1) medical therapy only; (2) revascularization if both plaque echolucency and stenosis progression to >90% are present; (3) revascularization only if plaque echolucency is present; (4) revascularization only if stenosis progression >90% is present; or (5) either plaque echolucency or stenosis progression is present. Risks of clinical events, costs, and quality-of-life values were estimated based on published sources and the analysis was conducted from a healthcare system perspective for asymptomatic patients with 70% to 89% carotid stenosis at presentation. Patients who did not undergo revascularization had the highest stroke events (17.6%) and lowest life-years (8.45), while those who underwent revascularization on the basis of either presence of plaque echolucency on ultrasound or progression of carotid stenosis had the lowest stroke events (12.0%) and longest life-years (14.41). The either plaque echolucency or progression-based revascularization group had an incremental cost-effectiveness ratio of $110 000/quality-adjusted life years compared with the plaque echolucency-based strategy, which had an incremental cost-effectiveness ratio of $29 000/quality-adjusted life years compared with the joint echolucency and progression-based strategy. Conclusions Plaque echolucency on ultrasound can be a cost-effective tool to identify patients with asymptomatic carotid artery stenosis most likely to benefit from carotid endarterectomy.

Background & Aims: Upper gastrointestinal bleeding is a common emergency and rebleeding is associated with an increased risk of death. Proper assessment of high-risk lesions and appropriate endoscopic hemostasis are required for the best outcomes. The endoscopic Doppler probe examination (DPE) allows for a more complete assessment of the stigmata of hemorrhage, providing better evaluation of the need for endoscopic hemostasis and determination of its completeness. We aimed to evaluate whether use of the DPE provides an additional advantage in cost and effectiveness compared with traditional endoscopic visual assessment (TEA) of high-risk stigmata in patients with nonvariceal upper gastrointestinal bleeding., Methods: We drew a decision tree representing the choice between DPE and TEA approaches for patients undergoing an index endoscopy for active nonvariceal upper gastrointestinal bleeding. Clinical probabilities were retrieved from randomized controlled trial data. Costs were expressed in 2017 US dollars. A third-party payer perspective was adopted. We performed deterministic and probabilistic sensitivity analyses. The adopted time horizon was 30 days after the index endoscopy., Results: We found that DPE is a dominant strategy over the TEA, in that DPE is more efficacious (92.6% of patients avoiding rebleeding vs 78.6% for TEA) and less expensive ($8502 vs $9104 for TEA). The economic dominance of DPE over TEA was robust to sensitivity analyses across all assumptions of the model when varied among ranges spanning 30% of their respective baseline values., Conclusions: In a cost-effectiveness analysis, we found DPE to be an economically dominant strategy to TEA (the traditional approach) in the management of high-risk lesions in patients with nonvariceal upper gastrointestinal bleeding. DPE was less costly and more effective., (Copyright © 2019 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Objective: Laboratory investigations are invasive methods. Magnetic resonance imaging (MRI) has a small field of view. Ultrasound can be performed at multiple parts of the body. The objective of the study was to find out subclinical synovial hypertrophy in systemic lupus erythematosus patients using gray-scale/power Doppler ultrasonography., Methods: A total of 247 systemic lupus erythematosus (without musculoskeletal involvement) patients from 21 February 2017 to 28 October 2018 were included in the cross-sectional study. Patients were subjected to physical examinations, laboratory tests, and gray-scale/power Doppler ultrasonography examinations. Synovial hypertrophy was confirmed if it was present in at least 4 out of 100 of the examined location sites. MRI examinations were performed for confirmation purposes. Spearman correlation was performed between imaging and laboratory investigations at the 99% confidence level., Results: No correlation was observed for results of synovial hypertrophy between physical examinations/laboratory tests and gray-scale/power Doppler ultrasonography examinations except erythrocyte sedimentation rate (r = 0.354). Cost of laboratory tests (315.47 ± 19.15 ¥/person) for subclinical synovial hypertrophy detection was higher than that of gray-scale/power Doppler ultrasonography examinations (135.47 ± 8.17 ¥/person, P <0.0001, q = 230.87). Results of gray-scale/power Doppler ultrasonography have a correlation with results of MRI (r = 0.34)., Conclusion: Only perform gray-scale/power Doppler ultrasonography examinations for regular maintenance of rheumatologic disease in systemic lupus erythematosus patients., (© 2019 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.)

Objective: The aims of the study were to identify whether timing of venous thromboembolism diagnosis is associated with differences in patient outcomes and to perform a cost-effectiveness analysis of routine venous Doppler ultrasound at admission to inpatient rehabilitation, taking into account costs associated with prolonged inpatient rehabilitation length of stay, and development of pulmonary embolism., Design: This was a retrospective cohort study of 2312 consecutive patient discharges from a single inpatient rehabilitation facility for an 18-mo period. Cost-effectiveness model was built using TreeAge Healthcare Pro. The base case was constructed using probabilities and inpatient rehabilitation length of stay identified from retrospective analysis. Cost of Doppler ultrasound was obtained through the literature, and daily inpatient rehabilitation cost was obtained from the study institution., Results: Venous thromboembolism was diagnosed in 6.6% of patients. Asymptomatic patients diagnosed with venous thromboembolism on screening Doppler ultrasound had shorter inpatient rehabilitation length of stay (P = 0.045) and lower rate of pulmonary embolism (P < 0.001) and acute hospital transfer (P = 0.002) than those diagnosed after clinical symptoms developed. Use of routine Doppler ultrasound at inpatient rehabilitation admission was found to be cost-effective, with a total cost of US $20,265 per admission compared with $20,269 per admission without use of Doppler ultrasound at inpatient rehabilitation admission., Conclusions: Routine Doppler ultrasound screening for venous thromboembolism at inpatient rehabilitation admission is associated with improved patient outcomes without added cost per admission.

Purpose: Stenosis is the main cause of arteriovenous fistula (AVF) failure. It is still unclear whether surveillance based on vascular access blood flow (QA) enhances AVF function and longevity., Methods: We conducted a three-year follow-up randomized, controlled, multicenter, open-label trial to compare QA-based surveillance and pre-emptive repair of subclinical stenosis with standard monitoring/surveillance techniques in prevalent mature AVFs. AVFs were randomized to either the control group (surveillance based on classic alarm criteria; n = 104) or to the QA group (QA measured quarterly using Doppler ultrasound [M-Turbo®] and ultrasound dilution [Transonic®] added to classic surveillance; n = 103).The criteria for intervention in the QA group were: 25% reduction in QA, QA<500 mL/min or significant stenosis with hemodynamic repercussion (peak systolic velocity [PSV] more than 400 cm/sc or PSV pre-stenosis/stenosis higher than 3)., Results: At the end of follow-up we observed a significant reduction in the thrombosis rate in the QA group (0.025 thrombosis/patient/year in the QA group vs. 0.086 thrombosis/patient/year in the control group [p = 0.007]). There was a significant improvement in the thrombosis-free patency rate (HR, 0.30; 95% CI, 0.11-0.82; p = 0.011) and in the secondary patency rate in the QA group (HR, 0.49; 95% CI, 0.26-0.93; p = 0.030), with no differences in the primary patency rate between the groups (HR, 0.98; 95% CI, 0.57-1.61; p = 0.935).There was greater need for a central venous catheter and more hospitalizations associated with vascular access in the control group (p = 0.034/p = 0.029).Total vascular access-related costs were higher in the control group (€227.194 vs. €133.807; p = 0.029)., Conclusions: QA-based surveillance combining Doppler ultrasound and ultrasound dilution reduces the frequency of thrombosis, is cost effective, and improves thrombosis free and secondary patency in autologous AVF.

Objective: To compare Doppler-guided hemorrhoidal artery ligation (DGHAL) with circular stapled hemorrhoidopexy (SH) in the treatment of grade II/III hemorrhoidal disease (HD)., Background: DGHAL is a treatment option for symptomatic HD; existing studies report limited risk and satisfactory outcomes. DGHAL has never before been compared with SH in a large-scale multi-institutional randomized clinical trial., Methods: Three hundred ninety-three grade II/III HD patients recruited in 22 centers from 2010 to 2013 were randomized to DGHAL (n = 197) or SH (n = 196). The primary endpoint was operative-related morbidity at 3 months (D.90) based on the Clavien-Dindo surgical complications grading. Total cost, cost-effectiveness, and clinical outcome were assessed at 1 year., Results: At D.90, operative-related adverse events occurred after DGHAL and SH, respectively, in 47 (24%) and 50 (26%) patients (P = 0.70). DGHAL resulted in longer mean operating time (44±16 vs 30±14 min; P < 0.001), less pain (postoperative and at 2 wks visual analogic scale: 2.2 vs 2.8; 1.3 vs 1.9; P = 0.03; P = 0.013) and shorter sick leave (12.3 vs 14.8 d; P = 0.045). At 1 year, DGHAL led to more residual grade III HD (15% vs 5%) and a higher reoperation rate (8% vs 4%). Patient satisfaction was >90% for both procedures. Total cost at 1 year was greater for DGHAL [&OV0556;2806 (&OV0556;2670; 2967) vs &OV0556;2538 (&OV0556;2386; 2737)]. The D.90, incremental cost-effectiveness ratio (ICER) was &OV0556;7192 per averted complication. At 1 year DGHAL strategy was dominated., Conclusions: DGHAL and SH are viable options in grade II/III HD with no significant difference in operative-related risk. Although resulting in less postoperative pain and shorter sick leave, DGHAL was more expensive, took longer, and provided a possible inferior anatomical correction suggesting an increased risk of recurrence.

Background: Routine staging imaging for early-stage breast cancer is not recommended. Despite this, there is clinical practice variation with imaging studies obtained for asymptomatic patients with a positive sentinel node (SN+). We characterize the utility, cost, and clinical implications of imaging studies obtained in asymptomatic SN+ patients., Methods: A retrospective review was performed of asymptomatic, clinically node-negative patients who were found to have a positive sentinel node after surgery. The type of imaging, subsequent tests/interventions, frequency of additional malignancy detected, and costs were recorded., Results: From April 2009 to April 2013, a total of 50 of 113 (44%) asymptomatic patients underwent staging imaging for a positive sentinel node; 11 (22%) patients had at least 1 subsequent imaging study or diagnostic intervention. No instance of metastatic breast cancer was identified, with a total cost of imaging calculated at $116,905., Conclusions: Staging imaging for asymptomatic SN+ breast cancer demonstrates clinical variation. These tests were associated with low utility, increased costs, and frequent false positives leading to subsequent testing/intervention. Evidence-based standardization may help increase quality by decreasing unnecessary variation and cost., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: To determine the accuracy of audible arterial foot signals with an audible handheld Doppler ultrasound for identification of significant peripheral arterial disease as a simple, quick, and readily available bedside screening tool., Methods: Two hundred consecutive patients referred to an interprofessional wound care clinic underwent audible handheld Doppler ultrasound of both legs. As a control and comparator, a formal bilateral lower leg vascular study including the calculation of Ankle Brachial Pressure Index and toe pressure (TP) was performed at the vascular lab. Diagnostic reliability of audible handheld Doppler ultrasound was calculated versus Ankle Brachial Pressure Index as the gold standard test., Results: A sensitivity of 42.8%, a specificity of 97.5%, negative predictive value of 94.10%, positive predictive value of 65.22%, positive likelihood ratio of 17.52, and negative likelihood ratio of 0.59. The univariable logistic regression model had an area under the curve of 0.78. There was a statistically significant difference at the 5% level between univariable and multivariable area under the curves of the dorsalis pedis and posterior tibial models (p < 0.001)., Conclusion: Audible handheld Doppler ultrasound proved to be a reliable, simple, rapid, and inexpensive bedside exclusion test of peripheral arterial disease in diabetic and nondiabetic patients., (© The Author(s) 2015.)

Background: Screening of the radial artery prior to harvesting as a conduit for coronary bypass may be performed clinically by the Allen test or by Doppler ultrasound. In a developing country like ours, the use of resources for Doppler studies may be questioned when Allen tests lead to a low rate of clinical sequelae. However, the rare occurrence of hand ischemia may be devastating and could justify the routine use of Doppler screening. This study aimed to address this question., Methods: One hundred patients undergoing elective coronary artery bypass grafting were screened by the modified Allen test and Doppler ultrasound for suitability of use of a radial artery conduit. After harvesting, proximal and distal segments of the radial artery were subjected to histopathological examination., Results: Of the 95 patients deemed suitable for radial artery grafting, 6 had mild calcification on Doppler ultrasound and 9 had calcification on histopathological examination. While Doppler showed atherosclerosis in 9 patients, only 6 had histopathological evidence of this (false-positive rate 3%). Of the 6 patients with histopathologic evidence of atherosclerosis, 2 were negative on Doppler (false-negative rate 2%)., Conclusion: Routine preoperative Doppler screening of the radial artery in the setting of limited resources is not justified. On the other hand, the time-tested Allen test which is easy to perform, interpret, and reproduce can be safely used as the sole screening test to harvest the radial artery., (© The Author(s) 2015.)

Background: Computed tomographic angiography is a diagnostic tool increasingly used for preoperative vascular mapping in abdomen-based perforator flap breast reconstruction. This study compared the use of computed tomographic angiography and the conventional practice of Doppler ultrasonography only in postmastectomy reconstruction using a cost-utility model., Methods: Following a comprehensive literature review, a decision analytic model was created using the three most clinically relevant health outcomes in free autologous breast reconstruction with computed tomographic angiography versus Doppler ultrasonography only. Cost and utility estimates for each health outcome were used to derive the quality-adjusted life-years and incremental cost-utility ratio. One-way sensitivity analysis was performed to scrutinize the robustness of the authors' results., Results: Six studies and 782 patients were identified. Cost-utility analysis revealed a baseline cost savings of $3179, a gain in quality-adjusted life-years of 0.25. This yielded an incremental cost-utility ratio of -$12,716, implying a dominant choice favoring preoperative computed tomographic angiography. Sensitivity analysis revealed that computed tomographic angiography was costlier when the operative time difference between the two techniques was less than 21.3 minutes. However, the clinical advantage of computed tomographic angiography over Doppler ultrasonography only showed that computed tomographic angiography would still remain the cost-effective option even if it offered no additional operating time advantage., Conclusions: The authors' results show that computed tomographic angiography is a cost-effective technology for identifying lower abdominal perforators for autologous breast reconstruction. Although the perfect study would be a randomized controlled trial of the two approaches with true cost accrual, the authors' results represent the best available evidence.

Background: Ultrasound examination is both accurate and cost-effective for the confirmation of a clinical diagnosis of carpal tunnel syndrome. Previous studies have shown electrodiagnostic testing and ultrasound to be similar with regard to sensitivity and specificity. The purpose of this study was to compare the sensitivity and specificity of ultrasound and electrodiagnostic testing by using a validated clinical diagnostic tool as the reference standard., Methods: All consecutive patients referred to an upper-extremity practice for electrodiagnostic testing for any reason over a three-month period were recruited to participate in this study. All patients were evaluated with the use of the Carpal Tunnel Syndrome 6 (CTS-6) clinical diagnostic tool, and a score of ≥12 was considered positive for carpal tunnel syndrome. A positive finding on ultrasound was considered to be a cross-sectional area of the median nerve, measured just proximal to the level of the pisiform, of ≥10 mm(2). A positive finding on electrodiagnostic testing was a distal motor latency of ≥4.2 ms and/or a distal sensory latency of ≥3.2 ms. Sensitivity, specificity, and accuracy were calculated for ultrasound and electrodiagnostic testing with use of the CTS-6 as the reference standard., Results: With use of the CTS-6 as the reference standard, ultrasound had a sensitivity of 89% and a specificity of 90% in our series of eighty-five patients. Electrodiagnostic testing had a sensitivity of 89% and a specificity of 80%. The positive predictive value of ultrasound was 94% compared with 89% for electrodiagnostic testing. The negative predictive value of ultrasound was 82% compared with 80% for electrodiagnostic testing. Ultrasound was accurate in seventy-six (89%) of the eighty-five cases whereas electrodiagnostic testing was accurate in seventy-three (86%) of the eighty-five cases (p = 0.5)., Conclusions: While ultrasound will not replace electrodiagnostic testing in complicated or unclear cases, in a select group of patients with a positive CTS-6, ultrasound can be used to confirm the diagnosis of carpal tunnel syndrome with better specificity and equal sensitivity as compared with those of electrodiagnostic testing., Level of Evidence: Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence., (Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.)

Objective: The economic implications of strategies to improve prenatal screening for congenital heart disease (CHD) in low-risk mothers have not been explored. The aim was to perform a cost-effectiveness analysis of different screening methods., Methods: We constructed a decision analytic model of CHD prenatal screening strategies (four-chamber screen (4C), 4C + outflow, nuchal translucency (NT) or fetal echocardiography) populated with probabilities from the literature. The model included whether initial screens were interpreted by a maternal-fetal medicine (MFM) specialist and different referral strategies if they were read by a non-MFM specialist. The primary outcome was the incremental cost per defect detected. Costs were obtained from Medicare National Fee estimates. A probabilistic sensitivity analysis was undertaken on model variables commensurate with their degree of uncertainty., Results: In base-case analysis, 4C + outflow referred to an MFM specialist was the least costly strategy per defect detected. The 4C screen and the NT screen were dominated by other strategies (i.e. were more costly and less effective). Fetal echocardiography was the most effective, but most costly. On simulation of 10 000 low-risk pregnancies, 4C + outflow screen referred to an MFM specialist remained the least costly per defect detected. For an additional $580 per defect detected, referral to cardiology after a 4C + outflow was the most cost-effective for the majority of iterations, increasing CHD detection by 13 percentage points., Conclusions: The addition of examination of the outflow tracts to second-trimester ultrasound increases detection of CHD in the most cost-effective manner. Strategies to improve outflow-tract imaging and to refer with the most efficiency may be the best way to improve detection at a population level., (Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.)

Background: We sought to demonstrate that a well-staffed, surgeon-directed, critical care ultrasound program (CCUP) is financially sustainable and provides administrative and educational support for point-of-care ultrasound., Methods: The CCUP provides a clinical service and training as well as conducts research. Initial costs, annual costs (C), revenue (R), and savings (S) were prospectively recorded. Using data from the first 3 years, we calculated the projected C, R, and S at 5 years. We determined CCUP sustainability by C < R and C < R + S at 3 years and 5 years., Results: During 36 months, the CCUP covered four surgical intensive care units (55 beds). Start-up costs included one basic and one cardiovascular device per 25 beds and a data storage system linking reports and images to the electronic medical record ($203,650). Billing increased threefold from Years 1 to 3, with a 21% increase between Years 2 to 3. Yearly costs included 0.5 full-time equivalent (FTE) sonographer and 0.2 FTE surgeon ($106,025); this was increased to 1 FTE and 0.25 FTE, respectively, for Years 4 and 5. The total 3-year cost was $521,725 and projected to be $863,325 by Year 5. The total 3-year revenue was $290,775 and projected to be $891,600 at 5 years. The total 3-year savings associated with the CCUP was $600,035 and is projected to be $1,194,220. With the use of the C < R, the CCUP meets operating expenses at Year 3 and covers overall cost at 5 years. If savings are included, then the CCUP is sustainable by its third year and is potentially profitable by Year 5., Conclusion: A surgeon-directed CCUP is financially sustainable, addresses administrative issues, and provides valuable training in point-of-care ultrasound.

Objective: The purpose of this paper is to evaluate the efficacy and cost-effectiveness of the implantable Doppler system based on the analysis of the available scientific literature and clinical and cost data available in our hospital. The results of this system are compared to those of conventional free flap monitoring methods., Materials and Methods: The literature published between 1991 and 2011 was systematically reviewed. All available cost data were collected and several simulations were performed. A retrospective assessment of the efficacy of conventional methods in our hospital was also conducted., Results and Conclusion: The implantable Doppler system is more effective than the conventional methods used to monitor free flap perfusion. The mean flap salvage rate with the implantable Doppler was 21 percentage points higher (81.4 vs. 60.4). The excess cost compared to conventional methods was about CAD 120 per patient (about EUR 94). However, this excess cost can be compensated or even reversed, depending on the initial flap salvage rate in the health facility and the type of free flap (buried vs. non-buried)., (Copyright © 2012 Elsevier Masson SAS. All rights reserved.)

Background: Early accurate assessment of burn depth is important to determine the optimal treatment of burns. The method most used to determine burn depth is clinical assessment, which is the least expensive, but not the most accurate.Laser Doppler imaging (LDI) is a technique with which a more accurate (>95%) estimate of burn depth can be made by measuring the dermal perfusion. The actual effect on therapeutic decisions, clinical outcomes and the costs of the introduction of this device, however, are unknown. Before we decide to implement LDI in Dutch burn care, a study on the effectiveness and cost-effectiveness of LDI is necessary., Methods/design: A multicenter randomised controlled trial will be conducted in the Dutch burn centres: Beverwijk, Groningen and Rotterdam. All patients treated as outpatient or admitted to a burn centre within 5 days post burn, with burns of indeterminate depth (burns not obviously superficial or full thickness) and a total body surface area burned of ≤ 20% are eligible. A total of 200 patients will be included. Burn depth will be diagnosed by both clinical assessment and laser Doppler imaging between 2-5 days post burn in all patients. Subsequently, patients are randomly divided in two groups: 'new diagnostic strategy' versus 'current diagnostic strategy'. The results of the LDI-scan will only be provided to the treating clinician in the 'new diagnostic strategy' group. The main endpoint is the effect of LDI on wound healing time.In addition we measure: a) the effect of LDI on other patient outcomes (quality of life, scar quality), b) the effect of LDI on diagnostic and therapeutic decisions, and c) the effect of LDI on total (medical and non-medical) costs and cost-effectiveness., Discussion: This trial will contribute to our current knowledge on the use of LDI in burn care and will provide evidence on its cost-effectiveness., Trial Registration: NCT01489540.

Background: Early hepatic artery thrombosis (eHAT) after liver transplantation occurs in 3% of adults and 8% of children and often results in retransplantation. eHAT is initially asymptomatic and arterial patency is monitored with percutaneous Doppler ultrasound screening (pDUS). The aim of the study is to analyze the diagnostic accuracy of "continuous" Doppler registration (CONDOR) using an implantable miniature Doppler., Methods: This prospective observational study was conducted in 102 liver transplant recipients. Hepatic arterial signal is checked by CONDOR at least six times per day for the first 10 days after transplantation with comparison of diagnostic accuracy of CONDOR versus pDUS., Results: Extra investigations were performed after 48 (11%) regular pDUS where arterial patency was questioned: 32 extra pDUS, 14 computed tomography (CT) angiographies, and 2 reoperations. CT scan confirmed eHAT in 4 cases. In 10 cases of pDUS-suspected eHAT, where subsequent CT showed an open artery, the CONDOR signal was clearly pulsatile. In 2 of 4 patients with five eHATs, a weak arterial signal was inadvertently interpreted as an open artery (sensitivity of 60%). The accuracy for detection of eHAT increased from 93% (pDUS) to 99% (CONDOR). Using CONDOR, additional CT angiographies may be prevented in 10% of cases., Conclusion: CONDOR is a useful adjunct to pDUS because it reduces the false-positive rate of pDUS. Further development of the technique and analysis of the signal generated by CONDOR are needed to improve the sensitivity before CONDOR can replace pDUS as a reliable screening method for detection of eHAT.

The utility and cost-effectiveness of routine transplant renal DU as a screening test in the immediate postoperative period following pediatric renal transplantation has not been systematically evaluated. Our center's transplant protocol includes a routine DU on postoperative day 3, unless an earlier DU was obtained for a specific indication. We retrospectively evaluated 113 consecutive pediatric renal transplant recipients. Indication for DU (routine vs. non-routine), timing, results, and graft outcome data were collected. We determined whether the DU result affected patient management. Eighty routine DU examinations were evaluated. Thirty (37.5%) of the 80 routine DUs had abnormalities. Most abnormalities were minor and did not require intervention. One patient with a dysfunctional bladder had mild hydronephrosis; this led to a decision to increase the frequency of bladder catheterization. This was the only intervention based upon the routine DUs. Twenty percent of routine DUs revealed abnormalities that led to a follow-up study, but none of these studies led to an intervention. The incremental cost of each DU exceeded $1080 and the incremental cost-effectiveness ratio for a documented change in management exceeded $86, 400. Our results suggest that routine post-transplant DU is not cost-effective in pediatric renal allograft recipients., (© 2012 John Wiley & Sons A/S.)

Background: Excessive alcohol consumption may lead to the development of alcohol-related liver disease (ALD). Liver biopsy may be used in patients with suspected ALD to confirm the diagnosis, exclude other or additional liver pathologies, and provide accurate staging of the degree of liver injury in order to enable the prediction of prognosis and inform treatment decisions. However, as it is an invasive procedure that carries the risk of morbidity and mortality, current UK guidance recommends that biopsy is not required to confirm the diagnosis in patients with a high clinical suspicion of ALD in whom blood tests have excluded other causes of liver disease, unless it is necessary to confirm a diagnosis of acute alcoholic hepatitis in order to inform specific treatment decisions., Objectives: To evaluate the diagnostic accuracy, cost-effectiveness, and effect on patient outcomes of four non-invasive tests for liver fibrosis [the Enhanced Liver Fibrosis (ELF™) test (Siemens Healthcare Diagnostic Inc., Tarrytown, NY, USA), FibroTest (BioPredictive, Paris, France), FibroMAX (BioPredictive, Paris, France) and transient elastography (FibroScan(®); produced by EchoSens, Paris, France and distributed in the UK by Artemis Medical Ltd, Kent, UK)] in patients suspected of having ALD., Data Sources: A systematic review was undertaken to identify studies reporting the diagnostic and prognostic accuracy of the ELF test, FibroTest, FibroMAX, and FibroScan for the identification of liver fibrosis and associated conditions in patients with suspected ALD. The following databases were searched in January 2010: MEDLINE (from 1950 to January 2010), MEDLINE In-Process & Other Non-Indexed Citations (from 1950 to January 2010), EMBASE (from 1980 to January 2010), Cochrane Database of Systematic Reviews (from 1996 to January 2010), Cochrane Central Register of Controlled Trials (from 1898 to January 2010), Cochrane Methodology Register (from 1904 to January 2010), Database of Abstracts of Reviews of Effects (from 1995 to January 2010), HTA Database (from 1995 to January 2010), NHS Economic Evaluation Database (from 1995 to January 2010), Cumulative Index to Nursing and Allied Health Literature (from 1982 to January 2010), Web of Knowledge and Science Citation Index (from 1969 to January 2010)., Review Methods: Study quality was assessed using the QUADAS (Quality Assessment of Diagnostic Accuracy Studies) checklist. Owing to the heterogeneity of the studies, no formal meta-analysis was undertaken. A de novo mathematical model was constructed to estimate the incremental costs and incremental quality-adjusted life-years (QALYs) associated with alternative strategies compared with a biopsy-all strategy. The tests are assessed first as a replacement for liver biopsy, and secondly as an additional test prior to liver biopsy. Thirty-six scenarios were assessed for each non-invasive test strategy, which varied the sensitivity of biopsy, the anxiety associated with biopsy, sensitivity and specificity values and whether or not the biopsy was percutaneous or transjugular. For each scenario, threshold levels were reported where biopsying all patients was more cost-effective than the strategy for two parameters (the decreased level of abstinence associated with the strategy compared with biopsying all and the level of incidental QALY gain associated with biopsy)., Results: No studies were identified that specifically assessed the ELF test, although a study was identified that evaluated the diagnostic accuracy of the European Liver Fibrosis Test (essentially, the ELF test with the addition of age to the algorithm) compared with biopsy. Three studies of FibroTest, no relevant studies of FibroMax, and six studies of FibroScan assessing accuracy compared with biopsy in patients with known or suspected alcohol-related liver disease were identified. In all studies, the number of patients with suspected ALD was small, meaning that the estimated sensitivities and specificities were not robust. No conclusive estimate of the cost per QALY of each non-invasive test could be provided. Scenarios exist in which each of the strategies analysed is more cost-effective than biopsying all patients and, in contrast, scenarios exist in which each strategy is less cost-effective than biopsying all patients., Limitations: Study selection and data analysis were undertaken by one reviewer., Conclusions: No conclusive result can be provided on the most cost-effective strategy until further data are available. A large number of parameters require data; however, the following are selected as being of most importance: (1) the sensitivity and specificity of each non-invasive liver test (NILT) against biopsy at validated and pre-selected cut-off thresholds; (2) the influence of potential confounding variables such as current drinking behaviour and the degree of hepatic inflammation on the performance of NILTs; and (3) the likelihood, and magnitude, of decreases in abstinence rates associated with a diagnosis of significant ALD by diagnostic modality and the incidental gains in QALYs that may be associated with biopsy., Funding: The National Institute for Health Research Technology Assessment programme.

Background: The purpose of this study was to identify which age-related groups of hemodynamically stable blunt trauma patients will present a positive cost-to-benefit ratio, in regard to the screening of incidental findings on Focused Assessment with Sonography for Trauma (FAST)., Methods: We conducted a prospective study using retrospective data taken from the trauma registry of 6,041 consecutive hemodynamically stable blunt trauma patients who underwent FAST at our Level I urban trauma hospital during the year 2009. A receiver operating characteristic curve was used to determine whether age level is useful in detecting organ-/system-specific incidental findings in trauma patients undergoing FAST and to establish the required diagnostic cutoff value of this selected test. A cost-benefit analysis was then performed for the age-specific cutoff values of each organ/system evaluated by FAST., Results: We found 522 incidental findings in 468 patients (7.8%). Further diagnostic workup was instructed in 35% (168 of 468) of patients with incidental findings. The cost-benefit analysis for the age-specific cutoff values found in the receiver operating characteristic curve analysis showed that the project of screening for incidental findings on FAST was viable only when the ultrasound operator additionally searches the liver/biliary tree (≥43 years) and the kidneys (≥56 years)., Conclusions: A systematic examination of the liver and biliary tree and both kidneys of specific age groups during FAST screening of hemodynamically stable blunt trauma patients may disclose a potentially unknown pathology with a positive cost-to-benefit ratio.

Purpose: The aim of the study was to compare the cost-effectiveness of different imaging strategies for the diagnosis of pediatric intussusception using a decision analytic model., Methods: A Markov decision model was constructed to model effects of radiation exposure at the time of intussusception in a hypothetical cohort of 2-year-old children. The 2 strategies compared were ultrasound followed conditionally by contrast enema (US/CE) vs contrast enema (CE) alone. The model simulated short-term and long-term outcomes of the patients, calculating the average quality-adjusted life years (QALYs) and health care costs associated with each arm., Results: The use of ultrasound as a first-line diagnostic modality would result in a decrease of 79.3 and 59.7 cases of radiation-induced malignancy per 100,000 male and female children evaluated, respectively. For male and female children with intussusception, US/CE was both the most costly initial imaging strategy and the most effective compared with CE. The incremental cost-effectiveness ratios of US/CE to CE was $70,100 (boy) and $92,227 (girl) per quality-adjusted life years gained., Conclusions: In a Markov decision model of pediatric acute intussusception, initial US/CE was both the most costly and the most effective strategy., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Critically ill trauma patients with severe injuries are at high risk for venous thromboembolism (VTE) and bleeding simultaneously. Currently, the optimal VTE prophylaxis strategy is unknown for trauma patients with a contraindication to pharmacological prophylaxis because of a risk of bleeding., Methods and Findings: Using decision analysis, we estimated the cost effectiveness of three VTE prophylaxis strategies-pneumatic compression devices (PCDs) and expectant management alone, serial Doppler ultrasound (SDU) screening, and prophylactic insertion of a vena cava filter (VCF) -- in trauma patients admitted to an intensive care unit (ICU) with severe injuries who were believed to have a contraindication to pharmacological prophylaxis for up to two weeks because of a risk of major bleeding. Data on the probability of deep vein thrombosis (DVT) and pulmonary embolism (PE), and on the effectiveness of the prophylactic strategies, were taken from observational and randomized controlled studies. The probabilities of in-hospital death, ICU and hospital discharge rates, and resource use were taken from a population-based cohort of trauma patients with severe injuries (injury severity scores >12) admitted to the ICU of a regional trauma centre. The incidence of DVT at 12 weeks was similar for the PCD (14.9%) and SDU (15.0%) strategies, but higher for the VCF (25.7%) strategy. Conversely, the incidence of PE at 12 weeks was highest in the PCD strategy (2.9%), followed by the SDU (1.5%) and VCF (0.3%) strategies. Expected mortality and quality-adjusted life years were nearly identical for all three management strategies. Expected health care costs at 12 weeks were Can$55,831 for the PCD strategy, Can$55,334 for the SDU screening strategy, and Can$57,377 for the VCF strategy, with similar trends noted over a lifetime analysis., Conclusions: The attributable mortality due to PE in trauma patients with severe injuries is low relative to other causes of mortality. Prophylactic placement of VCF in patients at high risk of VTE who cannot receive pharmacological prophylaxis is expensive and associated with an increased risk of DVT. Compared to the other strategies, SDU screening was associated with better clinical outcomes and lower costs.

Background and Purpose: Limited data exist on the frequency and outcome of carotid artery disease in Pakistan. Such information would help guide the usefulness of screening for the condition in this low-middle income health care setting., Methods: A prospective, descriptive study was conducted among 3 large teaching hospitals in Karachi, Pakistan. Patients referred for carotid Doppler ultrasound examination were included if they had experienced a stroke or TIA within the previous month. The severity and morphology of carotid disease were characterized by trained technicians using standardized criteria. Demographic and risk factor data were collected at baseline, and the outcome of patients was assessed at least 6 months later., Results: A total of 672 patients underwent bilateral carotid Doppler ultrasound (1344 carotid examinations). The findings revealed 0% to 50% stenosis in 526 (78%), 51% to 69% stenosis in 57 (8%), 70% to 99% stenosis in 82 (12%), and total occlusion in 7 patients (1%). Potentially surgically correctable disease, defined as 70% to 99% carotid artery stenosis, was present in only 79 (12%) patients, of whom 47 (60%) were ipsilateral symptomatic, 15 (20%) asymptomatic, and 17 (20%) had status unknown. Outcome information at >or=6 months follow-up was available for 36 of the 47 (76%) surgically correctable and only 4 of these patients (12%) had undergone surgical or radiological intervention (carotid endarterectomy in 3 patients and carotid stenting in 1 patient)., Conclusions: The frequency of carotid artery disease of at least moderate severity is very low in patients with recent stroke or TIA and there is low utilization of high-cost, carotid intervention procedures in Pakistan. These data raise questions regarding the applicability and cost-effectiveness of routine carotid ultrasound screening in our country and similar population in Asia. The local socio-economic and clinical data do not support routine carotid Doppler ultrasound in every patient with stroke and TIA in Pakistan. Studies are warranted to determine predictors of significant carotid artery stenosis in stroke/TIA patients of our country to develop reliable stroke guidelines appropriate for local population.

Background: Recurrent hemarthroses in hemophilia results in synovitis and joint arthropathy. Primary prophylaxis when universally instituted at current doses can prevent joint deterioration but is expensive. Alternatively, the selective implementation of prophylaxis would require a more sensitive tool for detecting synovitis than possible with clinical surveillance or plain radiographs. Magnetic resonance imaging (MRI) is such a tool and is utilized for the evaluation of hemophilic joint disease (HJD). However, it is expensive, and requires sedation in younger children precluding its utility for monitoring of synovitis. Ultrasonography (USG) with power Doppler (USG-PDS) has been utilized to detect and quantitate synovial vascularity in other arthritides and could provide an equally effective but less costly tool for HJD, particularly in children who would not require sedation., Objectives: To determine whether USG-PDS is comparable to MRI in the evaluation of hemophilic synovitis., Patients: A prospective cohort of 31 subjects including 33 joints (knees, elbows, ankles) underwent dynamic contrast enhanced (DCE)-MRI and USG-PDS., Results: USG-PDS measurements of synovial thickness(r = 0.70, P < 0.0001) and synovial vascularity (r = 0.73, P < 0.0001) correlated strongly with those obtained with DCE-MRI. A cutoff of PDS intensity of 1.3 decibels (dB) per mm(2) was found to yield a sensitivity of 100% and a specificity of 94.1% in 17 joints with/without a history of hemarthroses. Pettersson radiographic scores correlated significantly with synovial thickness in adults but not children., Conclusions: Our data suggest that USG-PDS may be an inexpensive and easily implemented imaging tool for detecting hemophilic synovitis and could be useful in tailoring effective prophylaxis.

Purpose: The current study explores the substitution of ultrasound (US) for magnetic resonance imaging (MRI) of musculoskeletal (MSK) disorders by describing the recent use and costs of MSK imaging in the Medicare population, projecting these trends from 2006 to 2020, and estimating cost-savings involved in substituting MSK US for MSK MRI, when appropriate., Methods: The study used government-published data sets and de-identified Radiology Information System records exempt from institutional review board approval. From 1 year's MSK MRI records (n = 3,621), the proportion of cases in which US could be substituted for MRI was estimated. The use rates for 4 modalities of MSK imaging and average costs were determined from government Medicare data sets from 1996 to 2005. Regression analysis was used to project use rates from 2006 to 2020. The effect on costs of substitution was calculated., Results: For the Medicare population, although there has been a moderate overall increase (25.7%) in MSK imaging, MSK MRI has increased 353.5% from 1996 to 2005. Projected MSK imaging costs in 2020 are $3.6 billion, of which $2.0 billion will be for MRI. A study of 3,621 MSK MRI reports indicates that 45.4% of primary diagnoses and 30.6% of all diagnoses could have been made with MSK US. The substitution of MSK US for MSK MRI, when appropriate, would lead to savings of more than $6.9 billion in the period from 2006 to 2020., Conclusion: MRI MSK use has grown substantially from 1996 to 2005. The substitution of MSK US, when appropriate, would lead to large cost-savings for Medicare.

In 2001, the Agency for Healthcare Research and Quality recommended the use of ultrasound for the placement of central venous catheters (CVCs) as one of their 11 practices to improve patient care. These recommendations were based on the results of several randomized clinical trials showing significantly improved overall success as well as reductions in complications. This article will describe the practical aspects of using ultrasound to guide placement of CVCs in the internal jugular vein in a "how I do it" approach, as well as review the practice management and training aspects related to incorporating ultrasound into daily practice.

Central vascular access is sometimes required for hemodynamic monitoring and infusion of fluids and medications in the pediatric emergency department. In many cases, it is attempted after failed peripheral venous and intraosseous access. Some evidence exists demonstrating benefits of ultrasound (US)-guided central vascular cannulation in adults in emergency departments. With appropriate education in its use, US-guided cannulation of central veins in children is likely to be associated with less complications and greater success. In the pediatric emergency department, the femoral vein is the most practical central venous cannulation site. A sound educational and quality assurance program is necessary for US-guided cannulation in the pediatric emergency department.

Recurrent bleeding from acute peptic ulcer hemorrhage is problematic. Studies have shown that Doppler ultrasound (DOP-US) is useful in decreasing rebleeding. We analyzed associated costs and outcomes to better define the role of DOP-US versus Conventional (Forrest classification endoscopic stigmata) in the management of acute peptic ulcer bleeding. Two separate decision analyses were constructed. Recurrent bleeding, failed esophagogastroduodenoscopy (EGD) hemostasis, complications, and surgery rates were derived from medical literature. Costs were based on Medicare data. DOP-US is preferred over Conventional in acute peptic ulcer bleeding with average cost savings per patient ranging from 853 dollars (decision-tree modeling) to 1,160 dollars (Monte Carlo simulation). High-dose intravenous proton-pump inhibitors lowered rates of recurrent bleeding for both Conventional and DOP-US, resulting in a lower but still persistent average cost savings per patient for DOP-US (decision-tree modeling = 328 dollars, Monte Carlo simulation = 560 dollars). This decision analyses identified DOP-US as the preferred cost-minimizing strategy in acute peptic ulcer hemorrhage. Results of cost analyses were most dependent on hospitalization costs and recurrent bleeding rates.

Accompanying the rapid growth of interest in percutaneous vascular interventions, there has been increasing interest among cardiologists in performing noninvasive vascular testing using ultrasound. In an attempt to provide recommendations on the best practices in vascular laboratory testing, this report has been prepared by a writing group from the American Society of Echocardiography (ASE) and the Society for Vascular Medicine and Biology. The document summarizes principles integral to vascular duplex ultrasound--including color Doppler, spectral Doppler waveform analysis, power Doppler, and the use of contrast. Appropriate indications and interpretation of carotid artery, renal artery, abdominal aorta, and peripheral artery ultrasound imaging are described. A dedicated section summarizes noninvasive techniques for physiologic vascular testing of the lower extremity arteries--including measurement of segmental pressures and pulse volume plethysmography. The use of exercise testing in the evaluation of peripheral artery disease, ultrasound evaluation of the lower extremities after percutaneous revascularization, and the diagnosis and management of iatrogenic pseudoaneurysm (PSA) is also discussed. A section on the important topic of vascular laboratory accreditation is included. Finally, additional details regarding proper technique for performance of the various vascular tests and procedures are included in the Appendix.

Objectives: To determine whether less invasive imaging tests [ultrasound (US), magnetic resonance angiography (MRA), computed tomographic angiography (CTA) and contrast-enhanced MRA (CEMRA)], alone or combined, could replace intra-arterial angiography (IAA), what effect this would have on strokes and deaths, endarterectomies performed and costs, and whether less invasive tests were cost-effective., Data Sources: Electronic databases covering the years 1980-2003 inclusive, updated to April 2004. Key journals from 1990 to the end of 2002., Review Methods: The authors constituted a panel of experts in stroke, imaging, vascular surgery, statistics and health economic modelling. The accuracy of less invasive carotid imaging was systematically reviewed using Standards for Reporting of Diagnostic Accuracy (STARD) methodology, supplemented by individual patient data from UK primary research and audit studies. A systematic review of the costs of less invasive tests, outpatient clinics, endarterectomy and stroke was performed, along with a microcosting exercise. A model of the process of care following a transient ischaemic attack (TIA)/minor stroke was developed, populated with data from stroke epidemiology studies in the UK, effects of medical and surgical interventions, outcomes, quality of life and costs. A survey of UK stroke prevention clinics provided typical timings. Twenty-two different carotid imaging strategies were evaluated for short- and long-term outcomes, quality-adjusted life-years (QALYs) and net benefit., Results: In 41 included studies (2404 patients, median age 60-65 years), most data were available on 70-99% stenosis. CEMRA was the most accurate [sensitivity 0.94, 95% confidence interval (CI) 0.88 to 0.97; specificity 0.93, 95% CI 0.89 to 0.96], compared with US, MRA and CTA, which were all similar (e.g. for US: sensitivity 0.89, 95% CI 0.85 to 0.92; specificity 0.84, 95% CI 0.77 to 0.89). Data for 50-69% stenoses and on combinations of tests were too sparse to be reliable. There was heterogeneity between studies for all imaging modalities except for CTA. The individual patient data (2416 patients) showed that the literature overestimated test accuracy in routine practice and that, in general, tests perform with higher sensitivity and specificity in asymptomatic than in symptomatic arteries. In the cost-effectiveness model, on current UK timings, strategies allowed more patients to reach endarterectomy very quickly, and where those with 50-69% stenosis would be offered surgery in addition to those with 70-99%, prevented most strokes and produced greatest net benefit. This included most strategies with US as first or repeat test, and not those with IAA. However, the model was sensitive to less invasive test accuracy, cost and timing of endarterectomy. In patients investigated late after TIA, test accuracy is crucial and CEMRA should be used before surgery., Conclusions: In the UK, less invasive tests can be used in place of IAA if radiologists trained in carotid imaging are available. Imaging should be carefully audited. Stroke prevention clinics should reduce waiting times at all stages to improve speed of access to endarterectomy. In patients presenting late after TIA, test accuracy is very important and US results should be confirmed by CEMRA, as patients with 50-69% stenosis are less likely to benefit. More data are required to define the accuracy of the less invasive tests, with improvements made in the data collection methods used and how data are presented. Consideration should also be given to the use of new technologies and randomised trials.

Objective: To investigate the impact and cost-effectiveness of carotid ultrasonographic examination on total risk stratification in low-medium risk hypertensive patients in relation to age (< 50 and > 50 years) and gender., Methods: Five hundred and eighty untreated hypertensives classified at low-medium risk, after the routine work-up recommended by the 2003 ESH/ ESC guidelines, were included in the study and total risk was reassessed by adding the results of carotid ultrasonography., Results: According to the stratification based on routine work-up 16.3% of the whole population was considered at low added risk and 83.7% at medium added risk. Carotid subclinical damage was found in 158 patients (27.0%), who were then reclassified in the high-risk stratum. Prevalence rates of patients reclassified in the high-risk stratum as a consequence of carotid damage were as follows: 12.6% in men < 50 years, 14.1% in women < 50 years, 53.0% in men > or = 50 years and 40.1% in women > or = 50 years. The cost per detected case of carotid atherosclerosis was 473 euro in patients < 50 years and 133 euro in those > or = 50 years., Conclusions: Our results show that: (i) the use of carotid ultrasonography allows a much more accurate identification of high-risk individuals; (ii) its impact and cost-effectiveness on the risk stratification process differs markedly according to the age and gender; (iii) the selective use of this procedure in subjects at high risk of target organ damage may substantially improve the cost of primary prevention.

Although childhood primary hypertension (CP-HTN) associated with obesity is considered an earlier manifestation of typical adult-onset primary hypertension (adult-HTN), the recommendations for diagnostic evaluation are not identical in the two conditions. In particular, renal imaging is not recommended in adult-HTN, but is still currently recommended in CP-HTN. In this study, the clinical value of renal imaging in the initial diagnostic evaluation of CP-HTN was determined. A retrospective chart review was conducted of older and overweight children (> 7 years of age) evaluated in the pediatric nephrology clinic at the University of Florida from 1999 to 2004 for hypertension. The final highly selected study group was composed of obese or overweight children (body mass index > 85th percentile for age and gender) with otherwise unremarkable history, physical examination, and urinalysis. Renal imaging was performed (ultrasound in 49, computed tomography in one) in 50 patients (M:F = 28:22; age range, 7-20 years) with clinical features compatible with CP-HTN, and was normal in all patients. In this study, renal imaging did not add any clinical value to the initial evaluation of CP-HTN associated with obesity. Larger studies may confirm that the evaluation of CP-HTN in older obese children could be similar to guidelines for evaluation of adult-HTN.

Background: Three medical conditions--cervical carotid artery disease, atrial fibrillation, and hypertension--cause the majority of strokes. Discovering these silent, immediate causes of stroke through screening, so they can be treated before stroke occurs, can potentially prevent strokes on an epidemiologic scale., Methods: A rapid, accurate, and cost-effective stroke prevention screening (SPS) protocol was developed., Results: The SPS protocol was used to screen 6,073 seniors residing in the central valley of California, at Madigan Army Medical Center, at New York University, and by the American Vascular Association at 68 leading institutions. The screening was estimated to have prevented 30 strokes and to have saved the health care system >$2 million., Conclusions: Implementation of a national SPS for seniors can discover the silent, immediate causes of strokes so they can be managed before stroke occurs and can potentially prevent the majority of strokes that we are currently not preventing.

Objectives: To examine the cost-effectiveness of Doppler ultrasonography in high-risk pregnancies., Methods: An analysis was made of the cost-effectiveness of Doppler ultrasonography in high-risk pregnancies in relation to different organizational models. National costs of Doppler ultrasonography for singleton pregnancies with intrauterine growth retardation were estimated for three models. The cost-effectiveness analysis was based on results from a meta-analysis on clinical effects, patient costs, immediate health care costs, and costs per "saved" perinatal death., Results: In the decentralized model (the current situation in Denmark), incremental health care costs were estimated to be 13.5 million DKK, with patient costs set at zero. In the regional and centralized models, the estimated costs were 9.3 million/0.9 million DKK and 3.4 million/2.6 million DKK, respectively. The incremental costs were more than outweighed by the savings made from significant reductions in obstetric interventions. The centralized model dominated the other two models in the cost-effective analysis. In the decentralized model, the costs of avoiding one perinatal death were estimated to be 1 million DKK. The sensitivity analysis suggested that the cost-effectiveness ratio differed considerably, depending on the assumptions used, although the rank order of the three models did not change., Conclusions: The cost-effectiveness analysis showed that a centralized model with five obstetric centers offering Doppler ultrasonography dominates the regional and decentralized models. However, even with the decentralized model (which reflects the current situation in Denmark), the costs of avoiding one perinatal death would seem to be reasonable. In view of the paucity of available cost and effects data and the sensitivity of the results to changes in the assumptions made, more reliable information is needed before a decision can be made regarding the organization of Doppler ultrasonography for high-risk pregnancies.

Objectives: To estimate the need for and the costs of carotid Doppler and carotid endarterectomy after stroke or TIA in non-selected hospitalized patients., Material and Methods: During 25 months hospitalized patients with stroke or TIA, in whom carotid endarterectomy could be relevant, were examined with carotid Doppler. If a significant stenosis was found, they were further evaluated for surgery. Based on our results, the requirement for future carotid endarterectomy and Doppler screening was estimated, and the costs of the procedures calculated., Results: Among 1351 patients 703 were screened with carotid Doppler. Forty-five had severe (70-99%) stenosis of the relevant carotid artery. Only 3 were operated on. The future costs of screening were estimated under different assumptions., Conclusion: Carotid endarterectomy is expensive due to the large number of patients screened with carotid Doppler per operated patient. A careful clinical selection of patients for screening is necessary.

Purpose: The purpose of this study was to evaluate the impact of Medicare coverage limitations and claim denials on noninvasive vascular diagnostic testing., Methods: All Medicare claims for noninvasive vascular diagnostic studies from January 1, 1999, to December 31, 1999, were identified from the hospital billing database according to Current Procedural Terminology codes for carotid artery duplex ultrasound scan, venous duplex ultrasound scan, and lower-extremity arterial Doppler scan. Reasons for Medicare denial of payment for these tests were reviewed and a cost analysis was performed., Results: During the 1-year period, there were 1096 noninvasive vascular diagnostic studies performed on Medicare patients. Of these 1096 tests, 176 (16.1%) were denied by Medicare (19.6% of 408 carotid duplex ultrasound scans, 16.8% of 345 venous duplex ultrasound scans, and 11.1% of 343 lower-extremity arterial Doppler scans). Of the noninvasive vascular tests denied by Medicare, an abnormal result was present in 72.5% of carotid duplex ultrasound scans, 32.8% of venous duplex ultrasound scans, and 78.9% of lower-extremity arterial Doppler scans. Overall, 88.1% of all initially denied claims (N = 176) were ultimately reimbursed by Medicare after resubmission, including 77.1% of the 118 claims denied based on compliance rules for "medical necessity.", Conclusion: Because of coverage limitations, Medicare denials of noninvasive vascular diagnostic tests can lead to potential uncompensated physician and hospital technical fees if denied claims are unrecognized. Vascular laboratories performing these tests need to review compliance with Medicare guidelines. Improvements may need to be made at both the provider and Medicare carrier levels in obtaining reimbursement for appropriately ordered noninvasive vascular diagnostic studies.

The gold standard for intraoperative evaluation of lower-extremity bypass grafts has been angiography. Limitations of this technique include inability to measure flow dynamics, violation of graft integrity, cost, and length of assessment time. The goal of this study was to evaluate duplex scanning as an alternative modality for intraoperative graft assessment. Our study group comprised of 19 consecutive patients undergoing infrainguinal bypass procedures at our institution between March 1999 and March 2000. Intraoperative angiography was compared with duplex scanning by evaluating parameters of assessment time, graft flow velocities, serum creatinine levels, and 30-day graft patency rates. Mean study times were the following: cut-film angiography, 22 +/- 1.8 minutes; real-time fluoroscopy, 17 +/- 2.5 minutes; and duplex imaging, 10.4 +/- 1.1 minutes. As noted duplex imaging times as compared with radiographic modalities were significantly shorter (P < 0.05). There was a substantial cost difference between angiography ($650) and duplex scanning ($350). A 100 per cent correlation of study findings was noted between angiography and duplex scanning. No significant change in pre- versus postoperative creatinine levels was found. We conclude that duplex scanning is an effective modality and provides reliable intraoperative vascular graft assessment data in a community hospital setting. Advantages include a shorter study time, lower cost, flow dynamic data acquisition, and avoidance of mechanical graft trauma.

Small formed elements and gas bubbles in flowing blood, called microemboli, can be detected using Doppler ultrasound. In this application, a pulsed constant-frequency ultrasound signal insonates a volume of blood in the middle cerebral artery, and microemboli moving through its sample volume produce a Doppler-shifted transient reflection. Current detection methods include searching for these transients in a short-time Fourier transform (STFT) of the reflected signal. However, since the embolus transit time through the Doppler sample volume is inversely proportional to the embolus velocity (Doppler-shift frequency), a matched-filter detector should in principle use a wavelet transform, rather than a short-time Fourier transform, for optimal results. Closer examination of the Doppler shift signals usually shows a chirping behavior apparently due to acceleration or deceleration of the emboli during their transit through the Doppler sample volume. These variations imply that a linear wavelet detector is not optimal. We apply linear and quadratic time-frequency and time-scale detectors to a set of noise-corrupted embolus data. Our results show improvements of about 1 dB using the time-scale detectors versus an STFT-based detector signifying that embolus detection is best approached as a time-scale problem. A time-scale-chirp detector is also applied and is found to have the overall best performance by about 0.5-0.7 dB while coming fairly close (about 0.75 dB) to a theoretical upper bound.

Purpose: Studies have confirmed an association between idiopathic deep vein thrombosis (DVT) and malignant tumors. We assessed the usefulness of routine abdominal sonography in patients with idiopathic DVT to detect malignant tumors and other relevant findings., Methods: We retrospectively analyzed abdominal sonograms and records from 135 consecutive patients with confirmed idiopathic DVT and interviewed patients and their physicians during the follow-up period (mean, 30 months). Malignancy and other clinically relevant findings determined by sonography were tabulated, and the cost of each malignancy detected by abdominal sonography in this study was calculated., Results: Malignant tumors were found in 14 patients (10%), 7 by routine abdominal sonography, 3 by other means during hospitalization, and 4 during the follow-up period. Other clinically relevant findings detected by routine abdominal sonography were found in 33 patients (24%). The estimated cost of discovering malignancy by using screening abdominal sonography was approximately US$3,000/malignancy., Conclusions: Abdominal sonography was useful in detecting a variety of clinically relevant findings in addition to half of the malignant tumors found in our study.

Hemodialysis access failure is a major cause of morbidity for patients with end stage renal disease with costs in excess of $743 million annually. Color-flow doppler ultrasound is the only mobile noninvasive technique that provides direct visual imaging of the access and measurement of access flow. Doppler ultrasound can identify patients at increased risk of future thrombosis and allow preventive intervention. Prospective trials show that ultrasound-based access management programs can decrease thrombosis rates, prolong access longevity, and decrease the cost of hemodialysis access management. It should be included as part of a coordinated program of hemodialysis management.

Background: The accuracy and convenience of venous ultrasound (VU) to exclude deep vein thrombosis (DVT) has led to indiscriminate use and low positive yield rates., Methods: A total of 256 patients were referred from our emergency department (ED) for stat VU during a 2-year period (1995 to 1996). The VUs were interpreted as normal in 198 (77%). Positive findings were discovered in 58 (23%), with DVT accounting for 43 (17%). Retrospective multivariant analysis was used to identify predictive indicators., Results: Unilateral leg swelling/edema identified 36 of 40 (90%) patients with DVT and 8 of 10 (80%) with other thrombotic disorders (saphenous and/or chronic venous thrombosis). A history of leg pain with prior DVT or recent trauma < or =3 days' duration increased DVT duration to 98% (39 of 40). Using these criteria, a 47% charge reduction would have been recognized., Conclusions: Improving ED screening criteria can safely increase yield rate and reduce charges with minimal loss of VU sensitivity.

Objectives: To investigate the effectiveness of two alternative vein-graft surveillance strategies. In the first strategy surveillance was restricted to patients with a possible higher risk of significant stenosis development, i.e., those with a moderate stenosis identified early after the operation. In the second strategy the effects of reducing the number of duplex tests per patient was examined., Patients and Methods: In a prospective study in three vascular surgical departments 300 patients (300 femoropopliteal or distal grafts) underwent duplex surveillance during the first year after the operation. The duplex-derived PSV-ratio was considered to represent the degree of stenosis. Arteriographic confirmation of suspected stenoses was routinely obtained, and patients without a suspected graft stenosis underwent a consented arteriogram during the first postoperative year. The decision to perform a graft revision was taken on the basis of an arteriographic stenosis of at least 70% diameter reduction. In the first strategy graft categories were defined on the basis of the first postoperative duplex examination: grafts with a PSV-ratio < 1.5, grafts with a PSV-ratio < 1.5-2.0, grafts with a PSV-ratio of 2.0-2.5, grafts with PSV-ratios 2.5-3.0, and grafts with PSV-ratios > 3.0. The primary patency rate at 12 months was compared for these categories. In the second alternative strategy the number of examinations and the percentage of event causing de novo stenoses were analysed per surveillance interval., Results: The presence of moderate abnormalities at the initial duplex scan did not identify patients with a high risk of an event, as initial PSV-ratios of 1.5-2.0 and 2.0-2.5 (early mild-moderate lesions) had comparable 12-month primary patencies to patients with a PSV-ratio < 1.5 (completely normal grafts): (63%, 73%, and 71%, respectively). The interval incidence of event causing de novo stenoses was 8% of the total number of duplex tests performed at 3 months, and 8% at 6 months after the operation. In patients who had no previous intervention for stenosis and had a normal bypass during the first 6 months postoperatively, a sharp drop in this incidence was seen at 9 and 12 months, with event causing de novo stenoses observed in only 2% and 1% of all duplex tests., Conclusions: All patients should be included in a surveillance program, as the presence of a normal vein graft at the first duplex examination does not rule out the subsequent development of graft stenosis. The duration of the surveillance period may be restricted to the first 6 months after operation in patients who have a normal bypass during that time period, as only few stenoses will be missed by this policy.

Unilateral parathyroid exploration with adenoma removal and identification of a normal parathyroid gland is an accepted surgical approach for the treatment of patients with primary hyperparathyroidism. This study prospectively evaluated the ability of high-resolution sonography to localize adenomas preoperatively and the effect of this localization on operative time and cost in 37 previously untreated patients undergoing surgical treatment for primary hyperparathyroidism. The sensitivity and positive predictive value of the sonographic examination were 84% and 90%, respectively. A true positive sonographic examination decreased surgical time by an average of 40 minutes and reduced operative charges by $564, including the cost of the test ($156). In experienced hands high-resolution sonography can be a cost-effective means of localizing parathyroid adenomas where unilateral exploration is considered an accepted surgical approach.