Comparison of virtual computed tomography enteroscopy using carbon dioxide with small-bowel enteroclysis and capsule endoscopy in patients with small-bowel tuberculosis.

OBJECTIVE: Comparison of virtual CT enteroscopy (VCTE) using carbon dioxide with small-bowel enteroclysis (SBE) and capsule endoscopy (CE) in small-bowel tuberculosis (SBTB). METHODS: This prospective study comprised consecutive patients suspected to have SBTB. VCTE and SBE were performed on the same day and evaluated by independent radiologists. CE was performed within 2 weeks. VCTE was performed following insufflation of carbon dioxide via catheters in the jejunum and anorectum. A contrast-enhanced CT was followed by a delayed non-contrast CT. Image processing was done using virtual colonoscopy software. Findings on VCTE, SBE, and CE were compared. The final diagnosis of SBTB was based on either histopathological or cytological findings, response to antitubercular treatment, or a combination of these. RESULTS: Of the 55 patients in whom VCTE was performed, complete data was available in 52 patients. A final diagnosis of SBTB was established in 37 patients. All patients had VCTE and SBE. CE was performed in 34 patients. Adequate luminal distension was achieved in all patients with SBE and 35 patients with VCTE. SBE showed more strictures in jejunum (10.8%) and ileum (75.7%) compared with VCTE (jejunum, 8.1%, and ileum, 64.9%) and CE (jejunum, 5.9%, and ileum, 61.8%). However, difference was not statistically significant. VCTE revealed a greater length of strictures in both the jejunum and ileum compared with SBE and CE. CONCLUSION: VCTE allows adequate evaluation of the bowel in most patients with SBTB. It allows detection of greater length of abnormality in jejunum and ileum compared with SBE and CE. KEY POINTS: • The use of VCTE using CO2 bowel insufflation in patients with SBTB should be considered. • VCTE allows detection of a greater length of abnormality in the jejunum and ileum.

How accurate is the label "allergic to iodinated contrast agents"?

BACKGROUND: Iodinated contrast agents (ICAs) are crucial to the use of many imaging studies. Reported allergies to ICAs in the medical record can interfere with optimal diagnostic imaging workups. PURPOSE: To investigate the accuracy with which the label "allergic to ICAs" is applied. MATERIAL AND METHODS: The medical records of 500 patients labeled "allergic to ICAs" at a single tertiary care hospital were reviewed. Patients were separated into three groups based on documentation in their medical records, as follows: Group 1, documented hypersensitivity reaction to ICAs; Group 2, documented ICA exposure with non-hypersensitivity adverse event (Group 2a) or without documented reaction (Group 2b); and Group 3, no documented prior exposure to an ICA. We then further reviewed the EMR to determine whether or not patients had subsequent administration of an ICA, whether or not they were given specific premedication, and whether or not they had a subsequent ICA-related event. RESULTS: A total of 16.6% of patients (n = 83) listed as "allergic to ICAs" had a documented hypersensitivity reaction following ICA administration (Group 1) while 58.6% (n = 293) of patients (Group 2) had a documented exposure to ICAs with either: (i) a non-hypersensitivity adverse event (23.5%, n = 69) or (ii) no record of a reaction to ICAs (76.5%, n = 224). The remaining 24.8% (n = 124), Group 3, had no record of exposure to an ICA, yet still carried the label. CONCLUSION: The majority of patients carrying the label "allergic to ICAs" had no record of a prior hypersensitivity reaction to ICAs.

Clinical imaging guidelines part 4: challenges in identifying, engaging and collaborating with stakeholders.

The effective development and use of clinical imaging guidelines requires an understanding of who the stakeholders are, what their interests in the process are, and what roles they should play. If the appropriate stakeholders are not engaged in the right roles, it is unlikely that clinical imaging guidelines will be successfully developed, relied on, and actually used. Some stakeholders are obvious: for the development of clinical imaging guidelines, both imagers and those who request examinations, such as general practitioners, internists, and medical specialists, must be involved. To gain acceptance, other relevant groups are stakeholders, including medical societies, other health care professionals, insurers, health IT experts and vendors, and patients. The role of stakeholders must be dictated by their specific interest. For some, involvement in the creation of guidelines is the right role. For others, such as regulators or insurers, reviews or invitations to comment are required, and for others, such as medical educators, it is probably sufficient to provide information and create awareness. Only through a careful consideration of who the stakeholders are and what are their interests are the successful development, acceptance, and use of clinical imaging guidelines likely to occur. Future efforts must focus on collaboration, particularly among groups that create clinical imaging guidelines and those that can support their use, and on regulatory roles and mandates.

Monitoring of clinical imaging guidelines part 3: norms, standards, and regulations.

It is known that the use of imaging in clinical situations is not always optimal, leading to suboptimal health care and potential radiation risk. There may be overuse of imaging, underuse, or use of the wrong modality. The use of clinical imaging guidelines is likely to improve the use of imaging, but roadblocks exist. Some of these relate to regulatory oversight and mandates. There is wide variation by country and region in the regulatory setting, ranging from actual absence of regulatory authorities to mandated availability of clinical imaging guidelines in the European Community. Collaborative efforts to ensure that clinical imaging guidelines are at least available is a good starting point. Regulatory oversight and support are necessary to ensure the use of clinical imaging guidelines. Regulations should address 3 areas: availability, clinical utilization, and adherence to and revision of guidelines. The use of both internal and external audits, with the aim of both use of and adherence to guidelines and quality improvement, is the best tool for enhancing use. The major challenges that need to be addressed, collaboratively, to ensure the dissemination and use of clinical imaging guidelines are the development of regulations, of regulatory structures that can be effectively deployed, and of benchmarks for adherence and for utility.

Clinical imaging guidelines part 2: Risks, benefits, barriers, and solutions.

A recent international meeting was convened by two United Nations bodies to focus on international collaboration on clinical appropriateness/referral guidelines for use in medical imaging. This paper, the second of 4 from this technical meeting, addresses barriers to the successful development/deployment of clinical imaging guidelines and means of overcoming them. It reflects the discussions of the attendees, and the issues identified are treated under 7 headings: ■ Practical Strategy for Development and Deployment of Guidelines; ■ Governance Arrangements and Concerns with Deployment of Guidelines; ■ Finance, Sustainability, Reimbursement, and Related Issues; ■ Identifying Benefits and Radiation Risks from Radiological Examinations; ■ Information Given to Patients and the Public, and Consent Issues; ■ Special Concerns Related to Pregnancy; and ■ The Research Agenda. Examples of topics identified include the observation that guideline development is a global task and there is no case for continuing it as the project of the few professional organizations that have been brave enough to make the long-term commitment required. Advocacy for guidelines should include the expectations that they will facilitate: (1) better health care delivery; (2) lower cost of that delivery; with (3) reduced radiation dose and associated health risks. Radiation protection issues should not be isolated; rather, they should be integrated with the overall health care picture. The type of dose/radiation risk information to be provided with guidelines should include the uncertainty involved and advice on application of the precautionary principle with patients. This principle may be taken as an extension of the well-established medical principle of "first do no harm."

2013 appropriate utilization of cardiovascular imaging: a methodology for the development of joint criteria for the appropriate utilization of cardiovascular imaging by the American College of Cardiology Foundation and American College of Radiology.

The American College of Radiology (ACR) and the American College of Cardiology Foundation (ACCF) have jointly developed a method to define appropriate utilization of cardiovascular imaging. The primary role of this method is to create a series of documents to define the utility of cardiovascular imaging procedures in relation to specific clinical questions, with the aim of defining what, if any, imaging tests are indicated to help to determine diagnosis, treatment, or outcome. The methodology accomplishes this aim through the application of systematic evidence reviews integrated with expert opinion by means of a rigorous Delphi process. By obtaining broad input during the development process from radiologists, cardiologists, primary care physicians, and other stakeholders, these documents are intended to provide practical evidence-based guidance to ordering providers, imaging laboratories, interpreting physicians, patients, and policymakers as to optimal cardiovascular imaging utilization. This document details the history, rationale, and methodology for developing these joint documents for appropriate utilization of cardiovascular imaging.

2013 appropriate utilization of cardiovascular imaging: a methodology for the development of joint criteria for the appropriate utilization of cardiovascular imaging by the American College of Cardiology Foundation and American College of Radiology.

The American College of Radiology (ACR) and the American College of Cardiology Foundation (ACCF) have jointly developed a method to define appropriate utilization of cardiovascular imaging. The primary role of this method is to create a series of documents to define the utility of cardiovascular imaging procedures in relation to specific clinical questions, with the aim of defining what, if any, imaging tests are indicated to help to determine diagnosis, treatment, or outcome. The methodology accomplishes this aim through the application of systematic evidence reviews integrated with expert opinion by means of a rigorous Delphi process. By obtaining broad input during the development process from radiologists, cardiologists, primary care physicians, and other stakeholders, these documents are intended to provide practical evidence-based guidance to ordering providers, imaging laboratories, interpreting physicians, patients, and policymakers as to optimal cardiovascular imaging utilization. This document details the history, rationale, and methodology for developing these joint documents for appropriate utilization of cardiovascular imaging.

ACR Appropriateness Criteria® acute chest pain--suspected pulmonary embolism.

Pulmonary embolism (PE) remains a common and important clinical condition that cannot be accurately diagnosed on the basis of signs, symptoms, and history alone. In the absence of high pretest probability and with a negative high-sensitivity D-dimer test, PE can be effectively excluded; in other situations, diagnostic imaging is necessary. The diagnosis of PE has been facilitated by technical advancements and multidetector computed tomography pulmonary angiography, which is the major diagnostic modality currently used. Ventilation and perfusion (V/Q) scans remain largely accurate and useful in certain settings. Lower-extremity ultrasound can substitute by demonstrating deep vein thrombosis; however, if negative, further studies to exclude PE are indicated. In all cases, correlation with the clinical status, particularly with risk factors, improves not only the accuracy of diagnostic imaging but also overall utilization. Other diagnostic tests have limited roles. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The development and review of the guidelines include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Long-term outcomes of transposed basilic vein arteriovenous fistulae.

The need for reliable, long-term hemodialysis vascular access remains critical. To determine the long-term outcomes of transposed basilic vein arteriovenous fistulae (BVT) and their comparability with other vascular accesses, we determined retrospectively the primary and secondary patency rates in 58 BVT and in a total of 58 arteriovenous fistulae (AVF) and arteriovenous grafts (AVG) at a single center. Fifty-eight BVT were placed in 57 individuals, 69% after prior vascular access failure. Ten BVT failed before initial use and 2 patients expired with functioning accesses before dialysis initiation. In all 58 BVT, 46.8+/-10.8% functioned at 3 years, with median survival 30.8 months. Limiting analyses to the 46 BVT that were ultimately accessed, 3-year primary and secondary patency rates were 38.3+/-7.7% and 56.5+/-12.6%, respectively. Lower ejection fraction (p=0.054) and greater numbers of prior permanent dialysis catheters (p=0.005) were present in those with failed BVT. Compared with AVF, BVT had similar 3-year primary and secondary patency rates. The secondary patency rate was significantly better for BVT vs. AVG over the observation period; at 3 years, the rates were 56.5+/-12.6% vs. 9.1+/-6.0% (p=0.002), respectively. Basilic vein arteriovenous fistulae are valuable hemodialysis accesses. Although nearly 20% of newly placed BVT will not function before first use, those that are functional have median survivals exceeding 6 years, and 38% will not require intervention within 3 years of initial use.

Cost determinants of percutaneous and surgical interventions for treatment of intermittent claudication from the perspective of the hospital.

PURPOSE: To identify pretreatment predictors of procedural costs in percutaneous and surgical interventions for intermittent claudication due to aortoiliac and/or femoropopliteal disease. METHODS: A retrospective study was conducted in 97 consecutive patients who underwent percutaneous or surgical interventions over 15 months at a tertiary care center. Nineteen clinical predictive variables were collected at baseline. Procedural costs (outcome) were assessed from the perspective of the hospital by direct calculation, not based on ratios of costs-to-charges. A multivariable regression model was built to identify significant cost predictors. Follow-up information was obtained to provide multidimensional assessment of clinical outcome, including technical success (arteriographic score) and clinical result (changes in ankle-brachial pressure index; cumulative patency, mortality, and complication rates). RESULTS: The linear regression model shows that procedural costs per patient are 25% lower in percutaneous patients (versus surgical), 42% lower for patients without rest pain than for those with, 28% lower if treated lesions are unilateral (versus bilateral), 12% lower if the treated lesion is stenotic rather than occlusive, 34% higher in sedentary patients, and 11% higher in patients with a history of cardiac disease. After a mean clinical follow-up >2 years, between-group differences between percutaneous and surgical patients were small and of limited significance in all dimensions of clinical outcome. CONCLUSION: Predictors of clinical outcome are different from predictors of costs, and one should include both types of variables in the decision-making process. The choice of percutaneous versus surgical strategy, the presence of rest pain, and the bilaterality of the culprit lesions were the main pretreatment determinants of procedural costs. When possible choices of treatment strategy overlap, percutaneous treatment should provide an acceptable result that is less expensive (although not equal to surgery).

Non-surgical salvage of thrombosed arterio-venous fistulae: a case series and review of the literature.

Attempts to salvage thrombosed hemodialysis arterio-venous fistulae (AVF) using interventional techniques are not universally performed. Patients often require temporary dialysis catheters pending creation of a new vascular access. We determined the long-term outcome of interventional (non-surgical) repair of completely thrombosed AVF in 49 consecutive accesses (22 radio-cephalic, 1 radio-basilic, 19 brachio-cephalic, and 7 brachio-basilic) referred for an intervention within 48 hours of thrombosis. Subjects were 65% male (32), with mean +/- SD age 63.7 +/- 13.5 years (range 33-91), 51% African-American (25), 47% Caucasian (23) and 65% had diabetes (32). Overall, 96% (47/49) of thrombosed AVF were salvaged with complications observed in four cases (two extravasations of contrast; two radial artery emboli), with no serious long-term sequelae. Interventional procedures included 34 venous angioplasties, 11 venous angioplasties with stenting and two combined venous and arterial angioplasties. The primary and secondary patency rates for all salvaged AVF were 50.5 +/- 8.7%, 72.5 +/- 7.8% at 1 year, and 43.3 +/- 10%, 55.4 +/- 12.7% at 2 years, respectively. The median estimate to first intervention after the declot procedure was 14.7 months. The median estimate for continued function exceeded 23.1 months. There was no significant statistical difference in the primary (p = 0.73) and secondary patency rates (p = 0.057) for forearm vs. upper arm AVF. We conclude that interventional repairs should routinely be employed to salvage newly thrombosed AVF. The vast majority of these individuals can avoid receiving dialysis catheters or placement of a new dialysis vascular access.

Günther Tulip filter retrievability multicenter study including CT follow-up: final report.

PURPOSE: To evaluate the safety and effectiveness of retrieval of the Günther Tulip inferior vena cava (IVC) filter. MATERIALS AND METHODS: This was a nonrandomized, single-armed, multicenter prospective investigation. Patients at temporary high risk for pulmonary embolism (PE) or deep vein thrombosis (DVT) who did not require a permanent filter were eligible. Forty-one patients received 42 Günther Tulip filters: 22 men and 19 women with a mean age of 47.7 years. Indications for filter placement included prophylaxis, PE, and DVT. Three months after filter retrieval, contrast agent-enhanced computed tomography of the abdomen, jugular vein ultrasonography, and clinical follow-up were performed. RESULTS: The filter retrieval rate was 57% (23 of 41). Günther Tulip filters were removed at a mean of 11.1 days (range, 2-14 d). The technical and clinical success rates for filter retrieval were both 100%. One placement complication and two protocol deviations occurred. These patients were excluded in terms of retrieval-related outcomes. One case of PE occurred with a filter in place, and one filter migrated to the heart. There were no acute complications caused by filter retrieval. At 3-month follow-up, there was no recurrent PE, DVT, jugular vein occlusion, or IVC stenosis or occlusion. CONCLUSION: In this multicenter study, retrieval of the Günther Tulip filter was safe and without recurrent thromboembolic events or evidence of IVC or jugular vein damage at 3-month follow-up.

Operating expenses for the diagnosis and treatment of peripheral vascular disease in an academic interventional radiology department: cost calculations according to a microeconomic method.

PURPOSE: A correct understanding of the true costs of a procedure is necessary to make informed decisions in cost-effectiveness analyses. The actual comprehensive costs of performing cardiovascular and interventional radiology (CVIR) procedures were analyzed in the present study, as opposed to charges or ratios of costs to charges (RCCs), as often used in the literature. MATERIALS AND METHODS: Costs included labor, equipment, administration, facility establishment and maintenance, overhead, and consumable supplies. Cost identification was initially performed with use of an hourly rate that reflected the cost of operating the CVIR section. This was then combined with the costs of the consumable supplies used during each type of procedure. Eight types of vascular procedures were studied in 235 consecutive patients to determine mean procedure duration and supplies consumption. Costs were then compared with charges and RCCs of these procedures. RESULTS: The hourly rate for operating one angiography suite was 690 dollars. Average cost by procedure, including hourly rate plus consumable supplies, were: aortic arteriogram, 1,442 dollars; aortobifemoral arteriogram, 1,554 dollars; unilateral limb arteriogram, 1,307 dollars; simple iliac or femoropopliteal angioplasty, 2,119 dollars; arterial stent placement, 2,780 dollars; percutaneous thrombectomy, 1,998 dollars; arterial in situ thrombolysis, 3,133 dollars; and arteriogram after thrombolysis, 926 dollars. RCCs calculated for each procedure ranged from 0.39 (thrombectomy) to 1.92 (control arteriography during or after thrombolysis) and were lower than expected based on previous reports. CONCLUSIONS: The average actual costs of several common diagnostic and therapeutic procedures for peripheral vascular occlusive disease were established, allowing determination of the relative importance of different cost components. This methodology may serve as a template for future cost analyses.