Patient exposure and image quality of low-dose pulmonary computed tomography angiography: comparison of 100- and 80-kVp protocols

OBJECTIVE: Measures to reduce radiation exposure and injected iodine mass are becoming more important with the widespread and often repetitive use of pulmonary CT angiography (CTA) in patients with suspected pulmonary embolism. In this retrospective study, we analyzed the capability of 2 low-kilovoltage CTA-protocols to achieve these goals. MATERIALS AND METHODS: Ninety patients weighing less than 100 kg were examined by a pulmonary CTA protocol using either 100 kVp (group A) or 80 kVp (group B). Volume and flow rate of contrast medium were reduced in group B (75 mL at 3 mL/s) compared with group A (100 mL at 4 mL/s). Attenuation was measured in the central and peripheral pulmonary arteries, and the contrast-to-noise ratios (CNR) were calculated. Entrance skin dose was estimated by measuring the surface dose in an ovoid-cylindrical polymethyl methacrylate chest phantom with 2 various dimensions corresponding to the range of chest diameters in our patients. Quantitative image parameters, estimated effective dose, and skin dose in both groups were compared by the t test. Arterial enhancement, noise, and overall quality were independently assessed by 3 radiologists, and results were compared between the groups using nonparametric tests. RESULTS: Mean attenuation in the pulmonary arteries in group B (427.6 +/- 116 HU) was significantly higher than in group A (342.1 +/- 87.7 HU; P < 0.001), whereas CNR showed no difference (group A, 20.6 +/- 7.3 and group B, 22.2 +/- 7.1; P = 0.302). Effective dose was lower by more than 40% with 80 kVp (1.68 +/- 0.23 mSv) compared with 100 kVp (2.87 +/- 0.88 mSv) (P < 0.001). Surface dose was significantly lower at 80 kVp compared with 100 kVp at both phantom dimensions (2.75 vs. 3.22 mGy; P = 0.027 and 2.22 vs. 2.73 mGy; P = 0.005, respectively). Image quality did not differ significantly between the groups (P = 0.151). CONCLUSIONS: Using 80 kVp in pulmonary CTA permits reduced patient exposure by 40% and CM volume by 25% compared with 100 kVp without deterioration of image quality in patients weighing less than 100 kg.

Implementation of Evidence-Based Practices for Treatment of Alcohol and Drug Disorders: The Role of the State Authority

The current climate of increasing performance expectations and diminishing resources, along with innovations in evidence-based practices (EBPs), creates new dilemmas for substance abuse treatment providers, policymakers, funders, and the service delivery system. This paper describes findings from baseline interviews with representatives from 49 state substance abuse authorities (SSAs). Interviews assessed efforts aimed at facilitating EBP adoption in each state and the District of Columbia. Results suggested that SSAs are concentrating more effort on EBP implementation strategies such as education, training, and infrastructure development, and less effort on financial mechanisms, regulations, and accreditation. The majority of SSAs use EBPs as a criterion in their contracts with providers, and just over half reported that EBP use is tied to state funding. To date, Oregon remains the only state with legislation that mandates treatment expenditures for EBPs; North Carolina follows suit with legislation that requires EBP promotion within current resources.

A comparison of patient characteristics and 30-day mortality outcomes after transcatheter aortic valve implantation and surgical aortic valve replacement for the treatment of aortic stenosis: a two-centre study

AIMS: It is unclear whether transcatheter aortic valve implantation (TAVI) addresses an unmet clinical need for those currently rejected for surgical aortic valve replacement (SAVR) and whether there is a subgroup of high-risk patients benefiting more from TAVI compared to SAVR. In this two-centre, prospective cohort study, we compared baseline characteristics and 30-day mortality between TAVI and SAVR in consecutive patients undergoing invasive treatment for aortic stenosis. METHODS AND RESULTS: We pre-specified different adjustment methods to examine the effect of TAVI as compared with SAVR on overall 30-day mortality: crude univariable logistic regression analysis, multivariable analysis adjusted for baseline characteristics, analysis adjusted for propensity scores, propensity score matched analysis, and weighted analysis using the inverse probability of treatment (IPT) as weights. A total of 1,122 patients were included in the study: 114 undergoing TAVI and 1,008 patients undergoing SAVR. The crude mortality rate was greater in the TAVI group (9.6% vs. 2.3%) yielding an odds ratio [OR] of 4.57 (95%-CI 2.17-9.65). Compared to patients undergoing SAVR, patients with TAVI were older, more likely to be in NYHA class III and IV, and had a considerably higher logistic EuroSCORE and more comorbid conditions. Adjusted OR depended on the method used to control for confounding and ranged from 0.60 (0.11-3.36) to 7.57 (0.91-63.0). We examined the distribution of propensity scores and found scores to overlap sufficiently only in a narrow range. In patients with sufficient overlap of propensity scores, adjusted OR ranged from 0.35 (0.04-2.72) to 3.17 (0.31 to 31.9). In patients with insufficient overlap, we consistently found increased odds of death associated with TAVI compared with SAVR irrespective of the method used to control confounding, with adjusted OR ranging from 5.88 (0.67-51.8) to 25.7 (0.88-750). Approximately one third of patients undergoing TAVI were found to be potentially eligible for a randomised comparison of TAVI versus SAVR. CONCLUSIONS: Both measured and unmeasured confounding limit the conclusions that can be drawn from observational comparisons of TAVI versus SAVR. Our study indicates that TAVI could be associated with either substantial benefits or harms. Randomised comparisons of TAVI versus SAVR are warranted.

Endoleak detection with CT angiography in an abdominal aortic aneurysm phantom: effect of tube energy, simulated patient size, and physical properties of endoleaks

To analyze the detection of endoleaks with low-tube-voltage computed tomographic (CT) angiography.

Optimal Workflow and Process-Based Performance Measures for Endovascular Therapy in Acute Ischemic Stroke: Analysis of the Solitaire FR Thrombectomy for Acute Revascularization Study.

BACKGROUND AND PURPOSE We report on workflow and process-based performance measures and their effect on clinical outcome in Solitaire FR Thrombectomy for Acute Revascularization (STAR), a multicenter, prospective, single-arm study of Solitaire FR thrombectomy in large vessel anterior circulation stroke patients. METHODS Two hundred two patients were enrolled across 14 centers in Europe, Canada, and Australia. The following time intervals were measured: stroke onset to hospital arrival, hospital arrival to baseline imaging, baseline imaging to groin puncture, groin puncture to first stent deployment, and first stent deployment to reperfusion. Effects of time of day, general anesthesia use, and multimodal imaging on workflow were evaluated. Patient characteristics and workflow processes associated with prolonged interval times and good clinical outcome (90-day modified Rankin score, 0-2) were analyzed. RESULTS Median times were onset of stroke to hospital arrival, 123 minutes (interquartile range, 163 minutes); hospital arrival to thrombolysis in cerebral infarction (TICI) 2b/3 or final digital subtraction angiography, 133 minutes (interquartile range, 99 minutes); and baseline imaging to groin puncture, 86 minutes (interquartile range, 24 minutes). Time from baseline imaging to puncture was prolonged in patients receiving intravenous tissue-type plasminogen activator (32-minute mean delay) and when magnetic resonance-based imaging at baseline was used (18-minute mean delay). Extracranial carotid disease delayed puncture to first stent deployment time on average by 25 minutes. For each 1-hour increase in stroke onset to final digital subtraction angiography (or TICI 2b/3) time, odds of good clinical outcome decreased by 38%. CONCLUSIONS Interval times in the STAR study reflect current intra-arterial therapy for patients with acute ischemic stroke. Improving workflow metrics can further improve clinical outcome. CLINICAL TRIAL REGISTRATION: URL http://www.clinicaltrials.gov. Unique identifier: NCT01327989.

Open issues in transcatheter aortic valve implantation. Part 1: patient selection and treatment strategy for transcatheter aortic valve implantation.

An exponential increase in the use of transcatheter aortic valve implantation (TAVI) in patients with severe aortic stenosis has been witnessed over the recent years. The current article reviews different areas of uncertainty related to patient selection. The use and limitations of risk scores are addressed, followed by an extensive discussion on the value of three-dimensional imaging for prosthesis sizing and the assessment of complex valve anatomy such as degenerated bicuspid valves. The uncertainty about valvular stenosis severity in patients with a mismatch between the transvalvular gradient and the aortic valve area, and how integrated use of echocardiography and computed tomographic imaging may help, is also addressed. Finally, patients referred for TAVI may have concomitant mitral regurgitation and/or coronary artery disease and the management of these patients is discussed.

Enduring effects of evidence-based psychotherapies in acute depression and anxiety disorders versus treatment as usual at follow-up — A longitudinal meta-analysis

This meta-analysis examined the enduring efficacy of evidence-based psychotherapies (EBP) in comparison to treatment as usual (TAU) by examining effects from termination to follow-up for acute anxiety and depression in an adult outpatient population. It was hypothesized that EBPs might extend their efficacy at follow-up assessment (Tolin, 2010). METHOD: Longitudinal multilevel meta-analyses were conducted that examined the magnitude of difference between EBP and TAU. Targeted (disorder-specific) outcomes were examined, along with dropout rates at follow-up assessments. RESULTS: A total of 15 comparisons (including 30 repeated effect sizes [ES]) were included in this meta-analysis (average of 8.9 month follow-up). Small to moderate ES differences were found to be in favor of EBPs at 0-4 month assessments (Hedges' g=0.40) and up to 12-18 month assessments (g=0.20), indicating no extended efficacy at follow-up. However, the TAU-conditions were heterogeneous, ranging from absence of minimal mental health treatment to legitimate psychotherapeutic interventions provided by trained professionals, the latter of which resulted in smaller ES differences. Furthermore, samples where substance use comorbidities were not actively excluded indicated smaller ES differences. TAU-conditions produced slightly higher dropout rates than EBP-conditions. CONCLUSION: Findings indicate small and no extended superiority of EBP for acute depression and anxiety disorders in comparison to TAU at follow-up assessment. There are a limited number of studies investigating the transportability and lasting efficacy of EBP compared to TAU, especially to TAU with equivalent conditions between treatment groups.

Therapists under influence – Patient strategies and therapist reactions

Therapists having a positive influence on patients is a common view of psychotherapy. There is, however, an influence of patients on therapists too, which has received less attention. The more restricted and rigid patients are, the more limited the interpersonal behavior of others with which the get along well. In line with social psychological, interpersonal and clinical models they try to bring the therapist into an interpersonal position which suits them well. With 60 patients, common strategies have been rated: Good mood, Positive feedback, Negative feedback, Agenda setting, Provoking a response from the therapist, Negative reports about third persons, Fait accompli, Supplication, Self-promotion, Avoidance of contents, und Emotional avoidance. The rating procedure, frequencies, and therapist reactions upon these patient strategies will be reported

[Body-packer ; body-stuffer - a medical challenge]

Since the seventies, the practice of drug smuggling in the form of body packing has increased in the Western world. The goal of our study was to present an algorithm for the safe management of intracorporal drug transport based on clinical experience and current evidence. The retrospective study, conducted over the past four years in our hospital prison, analyzes and discusses the diagnostic and therapeutic concepts. Thirty-four patients hospitalized 37 times in a 48-month period were included. In 28 patients drug packages were identified. Only two patients suffered from serious complications. The study demonstrates that following a specifically designed management algorithm based on clinical experience and principles of evidence-based medicine can optimize risk management, improve quality assurance and patient safety.