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PubMedDate not supplied

Utility of stress testing and coronary calcification measurement for detection of coronary artery disease in women.

Accurate and safe diagnostic testing provides the crucial link between detection and optimal management of coronary artery disease (CAD). Noninvasive diagnostic testing for CAD may be less accurate in women than in men. Many noninvasive diagnostic modalities are available for this purpose. An exercise tolerance test provides an assessment of functional capacity and has the advantages of wide availability and low initial cost. However, exercise echocardiography may be the most cost-effective method for the initial assessment of coronary artery disease in intermediate-risk women owing to its higher sensitivity and specificity. Recent studies with electron-beam computed tomography reveal that women with no coronary calcification are very unlikely to have obstructive CAD. In symptomatic women with an intermediate likelihood of CAD, either an exercise treadmill test or exercise echocardiography is appropriate for initial screening and can provide useful prognostic information. Alternatively, an electron-beam computed tomographic scan with a 0 calcium score may spare many women with atypical chest pain or equivocal findings on an exercise tolerance test from undergoing more expensive stress imaging studies or coronary angiography. For high-risk symptomatic women, a more aggressive approach involving coronary angiography appears to be the preferred initial diagnostic strategy.

Algorithms↗
PubMed2002

Comparative analysis of locally adaptive image enhancement for 3D ultrasound images.

In this article we compare methods for locally adaptive preprocessing of 3D ultrasound (US) images and their different capabilities of enhancing diagnostically important anatomical structures. We show that suitability and optimization of methods depend on the objective of the preprocessing task, e.g., slice representation or volume rendering. This article analyzes which features should be used to control the enhancement algorithm For slice representations optimization of local statistics is appropriate to maintain diagnostically important structures. Features with good region separation properties are preferable for volume rendering tasks. We demonstrate our results with US images from clinical examinations.

Algorithms↗
PubMed2006

Comparative analysis between transcranial color duplex sonography and magnetic resonance angiography in patients with stroke.

BACKGROUND: Cerebrovascular diseases are among the most frequent diseases of the central nervous system. There are several diagnostic methods for cerebral blood vessels evaluation. The optimal test is characterized with low risk, availability and diagnostic certainty. Lately, the rapid development of transcranial color duplex sonography (TCCS) and magnetic resonance angiography (MRA) have shown that they are the most useful techniques for non-invasive investigation of cerebral blood vessels. PURPOSE: To compare transcranial color duplex sonography (TCCS) and magnetic resonance angiography (MRA) in the evaluation of patients with stroke. METHODS: Using TCCS, hemodynamic parameters were measured in intracranial arteries in 50 patients with ischemic stroke. Magnetic resonance angiography (MRA) was carried out in all patients during 1-5 days after sonography. According to TCCS findings, patients were divided into the following groups: I) group with normal findings; II) group with occlusion of middle cerebral artery (MCA) branches; III) group with MCA stenosis and IV) group with occlusion of MCA trunk. TCCS findings were compared with MRA findings, which were considered as a golden standard. Sensitivity, specificity, positive predictive value, negative predictive value and the overall accuracy of the test were determined. RESULTS: In all groups of patients, high levels of sensitivity, specificity, positive and negative predictive value were obtained. The certainty of TCCS in determining normal and pathologic findings of the intracranial arteries was at risk level less than 1%. CONCLUSION: TCCS is a safe and secure diagnostic modality which serves for fast and recurrent evaluation of intracranial vessels patency in the acute stroke phase and it is an imaging method with high sensitivity and specificity in determining the steno-occlusive intracranial lesions.

Blood Flow Velocity↗
PubMed2003

The STARD statement for reporting studies of diagnostic accuracy: explanation and elaboration.

The quality of reporting of studies of diagnostic accuracy is less than optimal. Complete and accurate reporting is necessary to enable readers to assess the potential for bias in the study and to evaluate the generalisability of the results. A group of scientists and editors has developed the STARD (Standards for Reporting of Diagnostic Accuracy) statement to improve the reporting the quality of reporting of studies of diagnostic accuracy. The statement consists of a checklist of 25 items and flow diagram that authors can use to ensure that all relevant information is present. This explanatory document aims to facilitate the use, understanding and dissemination of the checklist. The document contains a clarification of the meaning, rationale and optimal use of each item on the checklist, as well as a short summary of the available evidence on bias and applicability. The STARD statement, checklist, flowchart and this explanation and elaboration document should be useful resources to improve reporting of diagnostic accuracy studies. Complete and informative reporting can only lead to better decisions in healthcare.

Algorithms↗
PubMed2003

The STARD statement for reporting studies of diagnostic accuracy: explanation and elaboration.

The quality of reporting of studies of diagnostic accuracy is less than optimal. Complete and accurate reporting is necessary to enable readers to assess the potential for bias in the study and to evaluate the generalizability of the results. A group of scientists and editors has developed the STARD (Standards for Reporting of Diagnostic Accuracy) statement to improve the reporting the quality of reporting of studies of diagnostic accuracy. The statement consists of a checklist of 25 items and flow diagram that authors can use to ensure that all relevant information is present. This explanatory document aims to facilitate the use, understanding, and dissemination of the checklist. The document contains a clarification of the meaning, rationale, and optimal use of each item on the checklist, as well as a short summary of the available evidence on bias and applicability. The STARD statement, checklist, flowchart, and this explanation and elaboration document should be useful resources to improve reporting of diagnostic accuracy studies. Complete and informative reporting can only lead to better decisions in health care.

Algorithms↗
PubMed2003

The STARD statement for reporting studies of diagnostic accuracy: explanation and elaboration. The Standards for Reporting of Diagnostic Accuracy Group.

The quality of reporting of studies of diagnostic accuracy is less than optimal. Complete and accurate reporting is necessary to enable readers to assess the potential for bias in a study and to evaluate the generalisability of the results. A group of scientists and editors has developed the STARD (Standards for Reporting of Diagnostic Accuracy) statement to improve the quality of reporting of studies of diagnostic accuracy. The statement consists of a checklist of 25 items and flow diagram that authors can use to ensure that all relevant information is present. This explanatory document aims to facilitate the use, understanding and dissemination of the checklist. The document contains a clarification of the meaning, rationale and optimal use of each item on the checklist, as well as a short summary of the available evidence on bias and applicability. The STARD statement, checklist, flowchart, and this explanation and elaboration document should be useful resources to improve the reporting of diagnostic accuracy studies. Complete and informative reporting can only lead to better decisions in health care.

Advisory Committees↗
PubMedDate not supplied

MRI of patellar articular cartilage: evaluation of an optimized gradient echo sequence (3D-DESS).

Our purpose was to evaluate the diagnostic efficacy of a gradient-echo sequence optimized for cartilage imaging in patellar cartilage abnormalities and to compare it to a standard turbo-spin-echo sequence. Fifty-eight consecutive patients who underwent, within 3 months both MRI and arthroscopy or surgery, were included in the investigation. Two radiologists specializing in musculoskeletal imaging independently assessed axial three-dimensional double-echo steady state (3D-DESS) gradient-echo images and sagittal proton- and T2-weighted turbo-spin-echo images with regard to retropatellar cartilage abnormalities. Possible findings were: 0: normal, 1: cartilage softening, and 2: lesion of the articular surface. Inter- and intraobserver variability was assessed. For cartilage softening, the axial 3D-DESS sequence had a sensitivity of 73%, a specificity of 75%, and an accuracy of 70%. The corresponding results for the sagittal turbo-spin-echo sequence were 53%, 65%, and 62%. For surface lesions, the results for the 3D-DESS sequence were 43%, 92%, and 83% and for the turbo-spin-echo sequence were 60%, 92%, and 86%. Intra- and interobserver agreement was moderate (k = 0.59 and 0.45 [DESS], 0.6 and 0.46 [turbo -spin-echo]). We conclude that the 3D-DESS sequence is moderately accurate in detecting patellar cartilage abnormalities. Compared with the sagittal turbo-spin-echo sequence, the axial 3D-DESS sequence is superior in diagnosing cartilage softening but not surface lesions.

Adolescent↗
PubMed2006

How do I perform a lumbar puncture and analyze the results to diagnose bacterial meningitis?

CONTEXT: Diagnostic lumbar punctures (LPs), commonly used to rule out meningitis, are associated with adverse events. OBJECTIVE: To systematically review the evidence about diagnostic LP techniques that may decrease the risk of adverse events and the evidence about test accuracy of cerebrospinal fluid (CSF) analysis in adult patients with suspected bacterial meningitis. DATA SOURCES: We searched the Cochrane Library, MEDLINE (using Ovid and PubMed) from 1966 to January 2006 and EMBASE from 1980 to January 2006 without language restrictions to identify relevant studies and identified others from the bibliographies of retrieved articles. STUDY SELECTION: We included randomized trials of patients aged 18 years or older undergoing interventions to facilitate a successful diagnostic LP or to potentially reduce adverse events. Studies assessing the accuracy of biochemical analysis of the CSF for possible bacterial meningitis were also identified. DATA EXTRACTION: Two investigators independently appraised study quality and extracted relevant data. For studies of the LP technique, data on the intervention and the outcome were extracted. For studies of the laboratory diagnosis of bacterial meningitis, data on the reference standard and test accuracy were extracted. DATA SYNTHESIS: We found 15 randomized trials. A random-effects model was used for quantitative synthesis. Five studies of 587 patients compared atraumatic needles with standard needles and found a nonsignificant decrease in the odds of headache with an atraumatic needle (absolute risk reduction [ARR], 12.3%; 95% confidence interval [CI], -1.72% to 26.2%). Reinsertion of the stylet before needle removal decreased the risk of headache (ARR, 11.3%; 95% CI, 6.50%-16.2%). The combined results from 4 studies of 717 patients showed a nonsignificant decrease in headache in patients who were mobilized after LP (ARR, 2.9%; 95% CI, -3.4 to 9.3%). Four studies on the accuracy of biochemical analysis of CSF in patients with suspected meningitis met inclusion criteria. A CSF-blood glucose ratio of 0.4 or less (likelihood ratio [LR], 18; 95% CI, 12-27]), CSF white blood cell count of 500/muL or higher (LR, 15; 95% CI, 10-22), and CSF lactate level of 31.53 mg/dL or more (> or =3.5 mmol/L; LR, 21; 95% CI, 14-32) accurately diagnosed bacterial meningitis. CONCLUSIONS: These data suggest that small-gauge, atraumatic needles may decrease the risk of headache after diagnostic LP. Reinsertion of the stylet before needle removal should occur and patients do not require bed rest after the procedure. Future research should focus on evaluating interventions to optimize the success of a diagnostic LP and to enhance training in procedural skills.

Adult↗
PubMed1996

[Staged diagnosis of anorectal incontinence].

The complex function of the anal sphincter is established by different functional compartments. Additionally a wide range of incontinence therapies-surgical and conservative-are possible. Therefore a differentiated diagnostic procedure is necessary to indicate the optimal, individual therapy: symptom-orientated step-by-step incontinence diagnostic program. This starts with a basic coloproctological evaluation using patient's history, continence scores, inspection, palpation, proctoscopy and rectoscopy. Functional and morphological evaluation is done by anorectal manometry, endosonography and neurologic procedures. Only in special cases the following procedures are necessary in addition: defecography, transit-time studies, magnetic resonance imaging, colonoscopy, gynecological and urological diagnostics.

Diagnosis, Differential↗
PubMed1985

[Evaluation of the effectiveness of preoperative polychemotherapy of nephroblastomas in children by angiography, ultrasonic tomography and computed tomography].

The results of preoperative polychemotherapy of nephroblastoma in 14 children are presented. Ultrasonic tomography, computed tomography and angiography were performed in all the patients before and after medication. The findings on the efficacy of polychemotherapy were assessed on the basis of surgical evidence and, in particular, resected material examination. A high diagnostic value of all the methods was demonstrated and criteria of the effectiveness of preoperative polychemotherapy as evaluated by application of ultrasonic and computed tomography and angiography were worked out. Optimal terms of carrying out diagnostic procedures in patients with nephroblastoma during preoperative treatment are suggested.

Angiography↗
PubMed1985

Clinical magnetic resonance imaging with nuclear medicine correlation.

The current role of magnetic resonance imaging (MRI) in different organ systems is discussed and compared to nuclear medicine and to other available clinical diagnostic modalities. The value of optimizing radiofrequency pulse sequence selection to provide additional tissue characterization is also described. The results of nuclear medicine and MRI studies in 56 patients are compared to evaluate the clinical diagnostic contribution of each imaging modality for various pathological processes. In addition, the state-of-the-art MRI systems and future development in MRI technology with its potential contribution is defined.

Abdomen↗
PubMed1981

The role of nocturnal penile tumescence in differentiating between organic and psychogenic impotence: the first stage of validation.

A study was conducted to assess the validity of nocturnal penile tumescence (NPT) as a means of distinguishing between psychogenic and organic erectile failure (impotence). On the basis of independent clinical criteria, patients were assigned to one of four diagnostic categories--organic impotence, psychogenic impotence, mixed etiology, and uncertain etiology. The NPT characteristics of the patients in the organic and psychogenic groups were compared and decision rules formulated in order to provide optimal discrimination between the two diagnostic categories. A decision rule based on the maximum erectile response observed for each patient led to the correct diagnosis in 80% of cases. Accuracy was increased to 95% when a decision rule based on the maximum frequency of nocturnal erections was employed. The clinical value and limitations of NPT as a diagnostic procedure are discussed.

Adult↗
PubMed1993

[Probability in medicine].

The term "probability", apparently vague, is defined as the ratio of favourable and all cases, e. g. 1/4. Sometimes is expressed as "odds", in the above example 1:3. Mathematical (a priori) probability is calculated according to the following consideration: during accidental tossing of an intact coin the probability of head is 1/2. Statistical (a posteriori) probability is assessed experimentally. If randomization is not respected, the result is doubtful. We call it bias. Probabilities are multiplied (added) if one and (or) another phenomenon should occur. Phenomena which occur or do not occur are frequently governed by binomial division. According to the law of large numbers the a posteriori probability will become the closer to the a priori probability, the larger the number of experiments. Forecasts based on probability are made possible by interferential statistics. In this respect they differ from mere statistical description. Thus optimal decision is achieved under conditions of uncertainty, typical for medicine. This applies to diagnosis as well as treatment. In this way a cut-off value can be selected for a given diagnostic test to achieve an optimal combination of the resulting sensitivity and specificity and the probability of disease (health) in case of a positive (negative) finding can be expressed. The results of statistical testing (e. g. the effectiveness of treatment) is as a rule presented by means of the probability value p, as compared with error alpha which should be assessed in advance. It is, however, necessary to respect also an alternative hypothesis. The latter is unfortunately formulated only rarely.

Probability↗
PubMed1990

Papillary transitional-cell carcinoma of the upper urinary tract: a cytological review.

Urinary cytology is a well-accepted diagnostic procedure for bladder carcinomas but it is utilized less frequently for diagnosis of upper urinary tract tumors. Accurate diagnosis depends on a suitable specimen as well as knowledge of diagnostic traps. This review article with several case studies emphasizes the various techniques used to obtain optimal samples, correct interpretative criteria, and diagnostic pitfalls. Technological advances for objective grading and predicting the biological behavior of tumors are also discussed.

Aged↗
PubMed2002

Diagnosis and management of infectious esophagitis associated with human immunodeficiency virus infection.

Esophageal disease is a common complication and cause of morbidity in patients with human immunodeficiency virus (HIV) infection. Opportunistic infections are the leading cause of esophageal complaints and may be a predictor of poor long-term prognosis, presumably as a reflection of severe underlying HIV immunodeficiency. The esophagus may be the site of the first acquired immunodeficiency syndrome (AIDS)-defining opportunistic illness in a large number of patients. Barium esophagography and upper gastrointestinal endoscopy are diagnostic modalities, commonly used to evaluate esophageal complaints in patients with AIDS. Treatment for most etiologies of esophagitis generally has a high degree of success, with a resultant improvement in quality of life. In addition to optimizing antiretroviral therapy, a thorough diagnostic assessment of every HIV-infected patient with esophageal complaints is warranted, followed by timely and appropriate treatment.

AIDS-Related Opportunistic Infections↗
PubMed1995

Optimization of apple allergen preparation for in vivo and in vitro diagnostics.

The aim of our investigation was to obtain a well-characterized active apple extract suitable for both in vivo and in vitro diagnostics by a technically simple method. For this purpose, apple extracts were prepared by homogenization in potassium phosphate buffer or by precipitation in organic solvents and resolubilization in potassium phosphate buffer in the presence or in the absence of enzyme inhibitors. These extracts were comparatively investigated by means of SDS-PAGE, two-dimensional electrophoresis, immunoblotting, RAST inhibition, and prick test. The in vitro investigations indicated that extracts prepared by precipitation in organic solvents (diacetone alcohol) at -20 degrees C have a higher allergen activity than those prepared by extraction in aqueous solutions. From the in vivo tests (prick test), it was concluded that application of inhibitors of cytoplasmic enzymes (phenol oxidases, peroxidases, proteases) already during extraction is an essential precondition for active prick test solutions. Correspondingly, the extract obtained by solvent precipitation in the presence of enzyme inhibitors appeared to be most suitable for clinical application.

Allergens↗