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A new self-diagnostic test for biceps femoris muscle strains.

OBJECTIVE: We compared a self-performed diagnostic test that we have been using since 1987, with other commonly used clinical tests for biceps femoris muscle-strain injuries. SETTING: Private practice focusing on sports injuries. PATIENTS: One-hundred forty professional male soccer players (ages 17 to 33 years) with a history and clinical findings of a pulled hamstring muscle (patients with direct trauma were excluded) had an ultrasound-proven grade I or II biceps femoris muscle injury. INTERVENTIONS: In these ultrasound-positive patients, the "taking off the shoe" test (TOST) was performed by the patient himself on both the affected and unaffected legs; and the physician then performed the resisted range of motion, passive range of motion, and active range of motion tests. RESULTS: The TOST had a sensitivity and specificity of 100%, and a positive predictive value and an negative predictive value of 100% for biceps femoris injury as found on ultrasound. The other muscle tests had an average sensitivity of 57%, specificity of 100%, accuracy of 79%, and negative predictive value of 70%. CONCLUSION: This preliminary, nonblinded observational study of the TOST found it to be more reliable than other commonly used clinical tests for hamstring tears. The clinical value of this easy-to-perform test should be evaluated in a prospective fashion.

Adolescent↗

Management strategies and determinants of outcome in acute major pulmonary embolism: results of a multicenter registry.

OBJECTIVES: The present study investigated current management strategies as well as the clinical course of acute major pulmonary embolism. BACKGROUND: The clinical outcome of patients with acute pulmonary embolism who present with overt or impending right heart failure has not yet been adequately elucidated. METHODS: The 204 participating centers enrolled a total of 1,001 consecutive patients. The inclusion criteria were based on the clinical findings at presentation and the results of electrocardiographic, echocardiographic, nuclear imaging and cardiac catheterization studies. RESULTS: Echocardiography was the most frequently performed diagnostic procedure (74%). Lung scan or pulmonary angiography were performed in 79% of clinically stable patients but much less frequently in those with circulatory collapse at presentation (32%, p < 0.001). Thrombolytic agents were given to 478 patients (48%), often despite the presence of contraindications (193 [40%] of 478). The frequency of initial thrombolysis was significantly higher in clinically unstable than in normotensive patients (57% vs. 22%, p < 0.001). Overall in-hospital mortality rate ranged from 8.1% in the group of stable patients to 25% in those presenting with cardiogenic shock and to 65% in patients necessitating cardiopulmonary resuscitation. Major bleeding was reported in 92 patients (9.2%), but cerebral bleeding was uncommon (0.5%). Finally, recurrent pulmonary embolism occurred in 172 patients (17%). CONCLUSIONS: Current management strategies of acute major pulmonary embolism are largely dependent on the degree of hemodynamic instability at presentation. In the presence of severe hemodynamic compromise, physicians often rely on the findings of bedside echocardiography and proceed to thrombolytic treatment without seeking further diagnostic certainty in nuclear imaging or angiographic studies.

Acute Disease↗

Elective coronary angiography and percutaneous coronary intervention during uninterrupted warfarin therapy.

The management of patients anticoagulated with warfarin and referred for coronary angiography presents a substantial challenge to the physician who must minimize risks of periprocedural hemorrhage and thromboembolism. The aim of this study was to evaluate the feasibility and safety of performing diagnostic coronary angiography and percutaneous coronary intervention during uninterrupted warfarin therapy. Patients treated with warfarin were prospectively identified and enrolled in the study. Nineteen diagnostic cardiac catheterizations and six percutaneous coronary interventions were performed in 23 patients. The mean international normalized ratio was 2.4 +/- 0.5 (range, 1.8-3.5). Hemostasis was achieved with AngioSeal following 21 procedures and with Perclose following 4 procedures. No patient experienced a predefined endpoint. Specifically, no patient experienced procedure-related myocardial infarction, major or minor bleeding. We conclude that cardiac catheterization and percutaneous coronary intervention may be considered in the setting of uninterrupted warfarin therapy.

Aged↗

[Heart and sports medicine-history and perspectives].

The origin of sports medicine in the 19th and 20th century is listed. The same applies to the development of devices in the course of performance diagnostics. The required parameters for evaluation of the cardiopulmonary performance ability are mentioned in their historical context.The athlete's heart is described from its beginnings until today in its differently characterized clinical concepts. The secured facts are provided in detail in combination with modern investigation techniques.A particular sports medical merit in the area of cardiology is the investigation of the significance of the body periphery regarding the heart activity. The performance-limiting factors for the local aerobic dynamic endurance are specified in addition to the training methods for performance enhancement and the consequences for heart activity. The paper closes with a short description of the significance of sports medicine for today's rehabilitative cardiology.

Adaptation, Physiological↗

A clinical comparison of xeroradiography and film radiography for the detection of proximal caries.

Xeroradiographs and conventional film radiographs (D- and E-speed) were compared in a clinical study with the use of 1 complete-mouth radiographs for (1) the presence of interproximal caries and (2) the determination of the depth of interproximal caries with the use of 200 tooth surfaces. In addition, an analysis of correct classification rates making a comparison of the same techniques was conducted. The results with the use of ROC analysis indicated that when a comparison was made of xeroradiography and D- and E-speed film, all techniques were equally useful. A broad range of observer ROC area values was found, indicating that diagnostic performance varies greatly with observer. The results of the diagnostic decisions made on carious surfaces versus noncarious surfaces indicated that all techniques tested were similar: 90% correct for noncarious surfaces and 77% correct for carious surfaces.

Dental Caries↗

A prospective, comparative study of the para-aminobenzoic acid test and faecal elastase 1 in the assessment of exocrine pancreatic function.

BACKGROUND: The assessment of exocrine pancreatic insufficiency is part of the routine work-up of patients with persistent diarrhoea or suspected steatorrhoea. Direct and indirect tests for the diagnosis of exocrine pancreatic insufficiency have their drawbacks. Measurement of faecal elastase 1 by enzyme-linked immunoabsorbent assay is a simple, non-invasive, robust test for exocrine pancreatic insufficiency. METHODS: We performed a prospective comparison of the para-aminobenzoic acid test and faecal elastase 1 test in 45 patients being investigated for diarrhoea or suspected steatorrhoea. Details of clinical suspicion, imaging and response to treatment were recorded. RESULTS: Exocrine pancreatic function was normal in 20 patients with normal para-aminobenzoic acid and faecal elastase 1 levels. Eight patients had exocrine pancreatic insufficiency with low para-aminobenzoic acid and faecal elastase 1 levels, which improved with enzyme supplementation. In 14 of the 15 patients with low or borderline low para-aminobenzoic acid and normal faecal elastase 1 levels, a non-pancreatic cause was found; one patient had a false positive para-aminobenzoic acid test. Two had normal para-aminobenzoic acid but low faecal elastase 1 levels. One improved with pancreatic supplementation, and imaging revealed chronic pancreatitis. The other had a false positive faecal elastase 1 test related to profuse diarrhoea. CONCLUSIONS: Faecal elastase 1 estimation is a simple, non-invasive, robust test of exocrine pancreatic insufficiency, performed on an out-patient stool sample. Its diagnostic performance is superior to that of the para-aminobenzoic acid test in investigating patients with diarrhoea or suspected steatorrhoea.

4-Aminobenzoic Acid↗

PET tracer development--a tale of mice and men.

PET scanning is an emerging technology for the clinical evaluation of many disease processes in man. The vast majority of clinical positron emission tomography (PET) studies are performed using a single tracer, fluorodeoxyglucose. Despite the excellent diagnostic performance of this tracer, it has recognised limitations. New tracers offer the potential to both address these limitations, and to establish new applications for PET. Small animal PET is a logical technique for validating new tracers relevant to human diseases. However, interspecies differences in the handling of chemicals may significantly influence the handling of novel tracers. This requires caution in extrapolating findings in animals to expectations of performance in man. Already there are several examples where biodistribution studies in mice would not have predicted the clinical utility of existing PET tracers. Nevertheless, application of a systematic approach to tracer development is likely to speed transition of new tracers from animals into man.

Animals↗

Efficacy and effectiveness of liver screening program to detect fatty liver in the periodic health check-ups.

To determine whether the current liver screening program for fatty liver has sufficient scientific evidence to justify its continued implementation. The liver screening program to detect fatty liver was performed on 411 Japanese workers utilizing serum aspartate aminotransferase (ALT), alanine aminotransferase (AST), and gammaglutamyl transpeptidase (gamma-GTP). Based on the preceding studies, subjects with viral and alcohol hepatitis were excluded from the evaluation. The diagnosis of fatty liver was based on ultrasound findings. The program was evaluated by efficacy and effectiveness; efficacy was measured according to the receiver operating characteristic (ROC) curves in comparison with the Body Mass Index (BMI). Effectiveness, based on the efficacy determinations, was assessed by means of the positive predictive value (PPV) test performance, the disease characteristics, and the program price. The diagnostic performances of ALT and BMI were nearly acceptable but far from excellent. The areas under the curves of the two indices were 0.69 and 0.63, respectively and these were statistically equivalent. The PPV ranged from 15 to 28% where the prevalence of fatty liver was 12.3%. The price of the program was estimated at US 4 dollars per person based on the medical reimbursement fee rate. The efficacy of the liver screening program was found to be insufficient and BMI monitoring may provide a more suitable and inexpensive alternative. Furthermore, the effectiveness of the program is open to question, considering the generally benign prognosis of the disease in the absence of any accompanying morbid conditions and the high price of the program.

Adult↗

Usefulness of CT in patients with intestinal obstruction who have undergone abdominal surgery for malignancy.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of CT in determining the causes of intestinal obstruction in patients who have undergone abdominal surgery for malignancy. MATERIALS AND METHODS: We analyzed the CT scans of 55 patients with benign (n = 26) or malignant (n = 29) intestinal obstruction that developed after abdominal surgery for malignancy. After calculating the diagnostic accuracy of interpretations by three radiologists, we compared CT findings for benign and malignant intestinal obstructions with respect to peritoneal involvement patterns and other ancillary findings. Multivariate logistic regression analysis was used to determine the diagnostic performance of CT in revealing causes of obstruction. RESULTS: Diagnostic accuracies of the three radiologists were 67%, 75%, and 78%. CT findings indicating malignant obstruction were a mass at the site of obstruction or prior surgery, lymphadenopathy, or an abrupt transition zone and irregular bowel wall thickening at obstructed sites (p < .05). Conversely, the chance for benign obstruction increased when CT revealed mesenteric vascular changes, a large amount of ascites, or a smooth transition zone and smooth bowel wall thickening at the obstructed site (p < .05). With multivariate logistic regression analysis using two variables (a mass at the site of obstruction or prior surgery and lymphadenopathy), we calculated the overall accuracy of CT as 84% (46/55 patients). CONCLUSION: CT is useful in differentiating benign from malignant intestinal obstructions in patients who have undergone abdominal surgery for malignancy. However, CT has limitations in patients not having a demonstrable peritoneal mass.

Abdomen↗

Comparison of thyrotropin assays by relative operating characteristic analysis.

We compared two versions of a commercial double-site immunoradiometric assay for human thyrotropin, one of them claimed to show superior ability in apportioning euthyroid and hyperthyroid populations. Relative operating characteristic (ROC) analysis permits the calculation of the area under the ROC curve as an unbiased unit measure of diagnostic validity, and also yields an optimal decision point for separating the two populations, based on relative prevalences and locally perceived utilities of test outcomes. We examined 48 hyperthyroid and 50 euthyroid subjects with the original assay and with a later version from the same manufacturer and conclude that the latter demonstrates a small but significant superiority in diagnostic performance throughout the clinical range of interest. Furthermore, peak diagnostic efficacy is attained when the boundary between the two populations is set at 0.3 mIU/L. At this decision point, sensitivity is 58%, specificity is 96%, and the predictive value of a positive test is 75%.

Adult↗

Improved capacity of exercise electrocardiography in the detection of coronary artery disease by focusing on diagnostic variables during the early recovery phase.

The temporal distribution of the diagnostic information for the detection of coronary artery disease (CAD) provided by exercise-induced electrocardiographic (ECG) ST-segment amplitude changes in different ECG leads in men and women has not been fully investigated. To shed further light in this area, 1877 electrocardiograms selected from 8322 patients undergoing a routine exercise test on a bicycle ergometer were evaluated. ST-segment amplitude and the difference between heart rate-matched recovery and exercise ST-segment amplitudes (ST/HR difference) were measured. Coronary artery disease was verified angiographically in 669 patients and excluded in 1208 patients by angiography (n = 119), by myocardial scintigraphy (n = 250), or on clinical grounds (n = 839). The diagnostic performance of the 2 ECG methods used was assessed by constructing receiver operating characteristic curves for each sampling point every 12 seconds during 10 minutes of recovery as well as the last 4 minutes of exercise for the ST-segment amplitude. ST-segment amplitude performed better after exercise than during exercise and best within the first 2 minutes of recovery. Its diagnostic ability did not differ from the ST-amplitude hysteresis assessed by the difference between recovery ST-segment amplitude and exercise ST-segment amplitude at matched heart rate. Both methods performed better in men and the diagnostic information appeared mainly in leads I, -aVR, II, V 4 , V 5 , and V 6 . The best discrimination of CAD is provided by analysis of ST-segment amplitude changes in 6 specific leads early during the recovery phase. This information should be targeted by exercise ECG diagnostic methods.

Coronary Angiography↗

Performance of tPSA and f/tPSA for prostate cancer in Chinese. A systematic review and meta-analysis.

Performing a systematic review and meta-analysis to evaluate the diagnostic performance of the total prostate-specific antigen (tPSA) tests for diagnosis of prostate cancer among Chinese. Literatures related to diagnosis of prostate cancer by tPSA and the ratio of free to total PSA (f/tPSA) being retrieved in five electronic databases. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio (DOR) were pooled using random effects models. Summary receiver operating characteristic curves (SROC) used to summarize overall test performance. In total 10 studies meeting the inclusion criteria, 2256 patients were included. Among them 423 were patients of prostate cancer compared to 1833 were patients of benign prostate hyperplasia (BPH). The pooled sensitivity and specificity of tPSA>4.0 ng/ml, tPSA>10.0 ng/ml and f/tPSA<0.15 as threshold for the diagnosis of prostate cancer were heterogeneity. The areas under SROC (AUC) were 80, 85 and 87%, respectively (P<0.05). The pooled DOR were 8.44(95%CI: 4.45 approximately 16.00), 9.94(95%CI: 4.15 approximately 23.77) and 13.75(95%CI: 6.35 approximately 29.76), respectively (P<0.05). chi(2) test used for testing the heterogeneity. tPSA and f/tPSA made an important performance for diagnosis of prostate cancer in decade among Chinese. The use of f/tPSA<0.15 as threshold maintain a high prognostic accuracy for prostate cancer.

Asian People↗

The performance of SolarScan: an automated dermoscopy image analysis instrument for the diagnosis of primary melanoma.

OBJECTIVE: To describe the diagnostic performance of SolarScan (Polartechnics Ltd, Sydney, Australia), an automated instrument for the diagnosis of primary melanoma. DESIGN: Images from a data set of 2430 lesions (382 were melanomas; median Breslow thickness, 0.36 mm) were divided into a training set and an independent test set at a ratio of approximately 2:1. A diagnostic algorithm (absolute diagnosis of melanoma vs benign lesion and estimated probability of melanoma) was developed and its performance described on the test set. High-quality clinical and dermoscopy images with a detailed patient history for 78 lesions (13 of which were melanomas) from the test set were given to various clinicians to compare their diagnostic accuracy with that of SolarScan. SETTING: Seven specialist referral centers and 2 general practice skin cancer clinics from 3 continents. Comparison between clinician diagnosis and SolarScan diagnosis was by 3 dermoscopy experts, 4 dermatologists, 3 trainee dermatologists, and 3 general practitioners. PATIENTS: Images of the melanocytic lesions were obtained from patients who required either excision or digital monitoring to exclude malignancy. MAIN OUTCOME MEASURES: Sensitivity, specificity, the area under the receiver operator characteristic curve, median probability for the diagnosis of melanoma, a direct comparison of SolarScan with diagnoses performed by humans, and interinstrument and intrainstrument reproducibility. RESULTS: The melanocytic-only diagnostic model was highly reproducible in the test set and gave a sensitivity of 91% (95% confidence interval [CI], 86%-96%) and specificity of 68% (95% CI, 64%-72%) for melanoma. SolarScan had comparable or superior sensitivity and specificity (85% vs 65%) compared with those of experts (90% vs 59%), dermatologists (81% vs 60%), trainees (85% vs 36%; P =.06), and general practitioners (62% vs 63%). The intraclass correlation coefficient of intrainstrument repeatability was 0.86 (95% CI, 0.83-0.88), indicating an excellent repeatability. There was no significant interinstrument variation (P = .80). CONCLUSIONS: SolarScan is a robust diagnostic instrument for pigmented or partially pigmented melanocytic lesions of the skin. Preliminary data suggest that its performance is comparable or superior to that of a range of clinician groups. However, these findings should be confirmed in a formal clinical trial.

Algorithms↗

Performance of an immunoenzymatic assay for Cryptosporidium diagnosis of fecal samples.

We evaluated the diagnostic performance of a Cryptosporidium immunoenzymatic assay (ELISA). Fecal samples were collected from 94 HIV-seropositive patients. All specimens were processed with a commercially-available ELISA to detect C. parvum specific coproantigen and with a modified Ziehl-Neelsen stain (ZNm) microscope exam. Overall, sensitivity of the immunoenzymatic test was 100%, with a specificity of 96%; positive and negative predictive values were 89% and 100%, respectively. The commercial ELISA and ZNm proved to be valuable diagnostic tools for Cryptosporidium infection.

AIDS-Related Opportunistic Infections↗

Diagnostic and analytical performance of a screening panel for allergy.

Worldwide, allergic diseases are increasing in prevalence and incidence. Early assessment of the immunoglobulin E (IgE) sensitisation status has a major impact on clinical outcome and selection of therapeutic options. Recently, a number of new IgE-detecting test systems have entered the market, including screening tests allowing identification of a wide spectrum of sensitising allergens. We evaluated the analytical and diagnostic performance of the newly developed Allergy Screen test panel for atopy (Mediwiss Analytic, Moers, Germany). The evaluation was performed for four major respiratory and four major nutritional allergens in 142 patients with clinical suspicion of respiratory and/or food allergies. For all allergens, the test showed acceptable concordance to the skin-prick test and the in vitro IgE CAP system (Pharmacia, Freiburg, Germany). The analytical performance was acceptable, with CVs between 2 and 8% in the positive range and good dilution linearity (R=0.9735). Imprecision in the low IgE concentration range dramatically improved by lowering the cut-off value to 0.2 IU/mL IgE. In conclusion, the Allergy Screen panel yields reliable results in the detection of allergic sensitisation to common allergens.

Adolescent↗

Performance specifications for diagnostic x-ray equipment.

The specification of performance characteristics for diagnostic x-ray equipment involves an interplay between purchaser and supplier which often results in inadequate understanding of imaging requirements by the supplier, and unfulfilled expectations by the purchaser. A statement of performance specifications has been prepared and accompanies requests for bids distributed to suppliers. The statement is described in its general form; modifications bay be needed to adapt it to a specific radiographic system.

Humans↗

A failure to improve radiologists' performances in diagnosing pulmonary lesions by a computer-aided approach.

A traditional radiological evaluation of five lung diseases and their computer-aided diagnosis with Bayes' approach, were based on the plain chest film. Parameters of diagnostic performance for 12 radiologists, who made 1224 diagnoses by each method, were compared. Under the conditions of this study the use of a computer-aided method did not improve radiologists' performances independently of their diagnostic ability and experience.

Bronchial Neoplasms↗

A new Doppler signal enhancing agent for flow assessment in breast lesions.

OBJECTIVE: To determine the diagnostic performance of SonoVue (Bracco) in the enhancement of Doppler signals in breast lesions and in the improvement of diagnostic accuracy. METHODS: This multicenter study included 220 patients undergoing investigations of parenchymal lesions, 40 of which had breast tumors. After a baseline Doppler examination, intravenous doses of 0.3, 0.6, 1.2 and 2.4 ml SonoVue were injected. Doppler signal quality before and after injection was compared. Off-site assessment of the global quality of Doppler signal and duration of clinical useful enhancement, as well as off-site and on-site evaluation of quality of color and spectral Doppler, were performed. On-site evaluation of diagnostic accuracy was also carried out. Safety assessments included monitoring of adverse events up to 24 h following the last injection of SonoVue. RESULTS: On-site evaluations: baseline Doppler was conclusive in only 4/21 carcinomas and in 2/17 benign lesions. Enhanced Doppler improved differential diagnosis in 20/21 carcinomas and in 9/12 benign lesions. Time to color enhancement was 0.55 min for the lowest and 0.35 min for the highest dose. The total duration of enhancement was 3.47 min for the lowest and 5.62 min for the highest dose, respectively. Off-site assessment: SonoVue improved the quality of Doppler blood flow information both in parenchymal and focal lesions. Statistically significant changes from baseline in global quality of Doppler investigations were observed at all four SonoVue doses (P<0.05). The duration of clinically useful signal enhancement increased with doses and a significant dose relationship was obtained (P<0.001). Mild adverse events were observed in two patients only. CONCLUSION: The results obtained from this study, following both off-site and on-site assessment, demonstrate that the administration of SonoVue to patients with focal breast lesions provides significant improvement over the baseline of Doppler signal quality and a clinically useful duration of signal enhancement, related to the dose. SonoVue was shown to be a safe and well-tolerated compound.

Adult↗