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At least 199 records · Page 11Linked to original sources
PubMed1992

[Dose requirements for projection techniques in x-ray diagnosis].

The dose required in x-ray diagnosis depends upon the demands made on a diagnostically optimal x-ray film or in fluoroscopy, and upon the technical quality of the equipment. The actual dose requirement, derived from field studies, is juxtaposed on the basis of representative examples with the maximum permissible dose requirement in accordance with the prescribed minimum sensitivity values of the x-ray film. The ideal dose requirement has been stated by Cohen et al. (1981) by a formula basing on parallel beam, maximum quantum yield and Bucky grid effect depending on the signal to noise ratio and object contrast. This was checked by means of contrast detail diagrams measured at the hole phantom, and was additionally compared with measurement results obtained by Wust et al. (1989) with acrylic glass phantoms. The optimal dose requirement is obtained by the maximum technically possible approach to the ideal requirement level. Examples are given, besides for x-ray equipment with Gd2 O2 S screen film systems for grid screen mammography, and new thoracic examination systems for mass screenings. Finally, a few values concerning the dose requirement or the analogous time required for fluorescent screening in angiography and interventional radiology, are stated, as well as for dentistry and paediatric x-ray diagnostics.

Angiography↗
PubMed2001

[CBO guideline 'Breast cancer: screening and diagnosis'].

New developments in the diagnostic procedures for women with an increased risk for, or symptoms related to breast cancer led to development of new guidelines by a working group under the auspices of the Dutch Institute for Health Care Improvement, the Organisation of Comprehensive Cancer Centres and the National Breast Group of the Netherlands. Based on the best available evidence this working group formulated recommendations on the following topics: indications for screening within the population screening programme, screening outside the population screening programme, the diagnostic procedures of symptomatic and asymptomatic lesions in the breast and the organisation of the diagnostic work-up of patients with breast symptoms. The most important recommendations in the guidelines are: individual screening is recommended to certain groups of women who do not participate in the population screening programme, based on their risk profiles; available evidence does not support the extension of the population screening programme to women 40-49 years of age; diagnosis and treatment have to take place in a structured context, the so-called breast team; to guarantee optimal diagnostic procedures a multidisciplinary clinic is mandatory; the diagnostic work-up of breast abnormalities is based on the triple assessment: physical examination, imaging by mammography and/or ultrasound and needle biopsy. For quality-controlled implementation of this guideline, uniform prospective registration of patients, diagnosis and treatment related data is an important condition.

Adult↗
PubMed1992

[Improvement of the diagnostic value of exercise test by heart-rate adjusted segment depression. Value of ST 20/HR index].

One of the new criteria of positivity of exercise stress testing proposed by Detrano and Kligfield is the ST/HR index, obtained by calculating the ratio of additional ST depression on exercise over the corresponding variation in the heart rate. These authors reported that this ratio improved the diagnostic value of the exercise stress test with respect to the traditional ST segment depression, but that the proportion depended on whether the index was measured 80 or 60 ms after the J point. The object of this study was to assess the diagnostic performance of the ST/HR index measured 0, 20, 40, 60 and 80 ms after the J point by automatic analysis and to compare these five diagnostic indices with the classical ST segment depression (standard criterion) by ROC graphs and the Mac Nemar test. One hundred consecutive patients (73 men and 27 women) all symptomatic, underwent submaximal or symptom-limited exercise stress testing and accepted coronary angiography. The prevalence of greater than or equal to 50% coronary stenosis on at least one main vessel was 48%. None had previous myocardial infarction. The ROC graphs and areas under the curve demonstrated generally the superiority of the ST/HR index over the standard criteria. The optimal diagnostic performance was observed when the index was calculated 20 ms after the J point (ST 20/HR index).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

The logic of imaging in spine surgery.

Spinal imaging has rapidly evolved into a complex diagnostic field requiring specialized expertise. While many imaging modalities reveal portions of a topographic map of the spine necessary for surgery, only magnetic resonance imaging emerges as the imaging modality of widest and most efficacious first choice. With the increasing high-technology sophistication of modern imaging modalities, the spine surgeon must become completely conversant with the radiologic data produced by these imaging techniques. The authors present a logical approach to spinal imaging--an algorithm--based on etiologic classification and aimed at conserving medical resources and developing an optimal diagnostic pathway for spine injury and disease. Spine surgeons are urged to incorporate the interpretative insights of radiologists into the diagnostic process.

Algorithms↗
PubMed1977

Clinical indications and accuracy of gray scale ultrasonography in the patient with suspected biliary tract disease.

One hundred patients with suspected biliary tract disease underwent gray scale cholecystosonography (GSCS) and had diagnostic confirmation by oral cholecystogram (OCG) and/or operation. Ultrasonography demonstrated the gallbladder in 94 of the 100 patients; 2 patients had had previous cholecystectomy and 3 of the 4 remaining patients had documented stones with no confirmation of a nonvisualizing OCG in the other patient. Among the 88 patients with OCG, GSCS findings correlated in 91 per cent (2 per cent false-positive; 7 per cent false-negative). Among the 43 operative patients, GSCS was proven correct in 91 per cent (no false positive; 9 per cent false-negative). Of 12 patients with jaundice GSCS correlated with operative findings in 75 per cent (no false-positive; 25 per cent false-negative). Diagnostic errors occurred in patients with very small biliary calculi, particularly when a single stone was impacted in the cystic duct. Failure to identify the gallbladder with ultrasound signifies probable cholelithiasis in the patient without previous cholecystectomy. On the basis of this experience, we conclude that (1) GSCS is most useful when jaundice or acute illness precludes conventional studies; (2) GSCS provides an inexpensive, quick, accurate means of diagnosing cholelithiasis with a very high specificity (97 per cent) and moderate sensitivity (88 per cent); and (3) GSCS is the optimal diagnostic procedure for evaluating the biliary tract in the acutely ill, jaundiced, vomiting, allergic, and/or pregnant patient.

Biliary Tract Diseases↗
PubMed1999

Sonography in the diagnosis of carpal tunnel syndrome.

OBJECTIVE: The few papers published on the use of sonography in carpal tunnel syndrome suggest it may be a useful diagnostic test. This study aims to prospectively evaluate the use of sonographic measurements of the median nerve in the diagnosis of carpal tunnel syndrome. SUBJECTS AND METHODS: Patients with documented carpal tunnel syndrome and a group of asymptomatic control subjects were enrolled and underwent high-resolution sonography of the carpal tunnel. A small-footprint linear array transducer was used to scan and measure the median nerve cross-sectional area and the maximum transverse and anteroposterior diameters. Data from the patient group and the control group were compared to establish optimal diagnostic criteria for carpal tunnel syndrome. RESULTS: Sixty-eight carpal tunnel syndrome patients (50 women, 18 men) with 102 affected nerves and 68 nerves in 36 asymptomatic controls (23 women, 13 men) were examined. Qualitative assessment alone was found to be unreliable. All measurements showed significant differences between patients and controls. The most predictive measurement was swelling of the median nerve, which was significantly greater in carpal tunnel syndrome patients compared with controls (mean, 0.13 cm2 versus 0.07 cm2). Thus, quantitative assessment of the median nerve provides an accurate diagnostic test (sensitivity, 82%; specificity, 97%), with an area larger than 0.09 cm2 being highly predictive of carpal tunnel syndrome. CONCLUSION: We confirm that median nerve cross-sectional area measurement correlates well with the presence of carpal tunnel syndrome and is both sensitive and specific for the diagnosis.

Carpal Tunnel Syndrome↗
PubMed2005

Antibiotic treatment and the diagnosis of Streptococcus pneumoniae in lower respiratory tract infections in adults.

OBJECTIVE: To analyze the possible influence of antibiotic treatment on the results of different diagnostic tests for the diagnosis of lower respiratory tract infections with Streptococcus pneumoniae. MATERIAL AND METHODS: A prospective cohort of 159 unselected adult immunocompetent patients admitted to Silkeborg County Hospital in Denmark with community-acquired lower respiratory tract infections underwent microbiological investigations with fiber-optic bronchoscopy with bronchoalveolar lavage, blood and sputum culture and urine antigen test for type-specific polysaccharide capsular antigens of S. pneumoniae. RESULTS: When stratified for antibiotic treatment prior to microbiological sampling, three different groups of patients with documented or probable infection with S. pneumoniae could be identified. The first group comprised 14 patients who were culture positive in one or more culture tests, where most (11/14) did not receive any antibiotic treatment within 24 hours of sampling. The second group consisted of nine patients with a positive urine antigen test where 8/9 and 9/9 received antibiotic treatment 24 and 48 hours, respectively, prior to urine sampling. Only a single patient was positive in both systems, making a total of 22 patients with documented pneumococcal infection. As a positive culture test was dependent on the absence of antibiotic treatment, whereas a positive urine antigen test depended on antibiotic treatment within 48 hours, the two tests were complementary in the diagnosis of infection with S. pneumoniae. The third group of patients with probable pneumococcal infection were identified as 26% and 20% of the remaining 137 patients with unknown or known non-pneumococcal etiology, respectively, who received recent antibiotic treatment within 2-4 weeks of diagnostic sampling. By comparison, 0% (p < 0.01) with documented pneumococcal infection received antibiotic treatment in weeks 2-4 prior to microbiological sampling. As such a further eight patients should be expected to have infection with S. pneumoniae but would test negative in both culture tests and the urine antigen test because of antibiotic treatment within weeks 2-4 prior to sampling. CONCLUSION: The diagnosis of infection with S. pneumoniae is very dependent on whether or not recent (within 2-4 weeks) or immediate (within 48 hours) antibiotic treatment has been given prior to microbiological sampling of patients. The results suggest an optimized diagnostic strategy with, if possible, sampling for culture prior to antibiotic treatment, while sampling for pneumococcal antigens should wait 24-48 hours for antibiotic treatment.

Adult↗
PubMed2006

Diagnosing ankylosing spondylitis.

This article focuses on the early diagnosis and effective management of ankylosing spondylitis (AS), a disease that is not uncommon and that can cause early retirement and severe functional disability. AS, like most other rheumatologic diseases, has no diagnostic gold standard. Correct diagnosis depends largely on a constellation of clinical symptoms and signs in addition to radiological findings. Early diagnosis has become all the more important because effective therapies are available: tumor necrosis factor antagonists that suppress disease activity and improve functional ability in patients with AS refractory to conventional drug therapy. The biologic agents are probably even more effective if given early. Inflammation of the sacroiliac joints and the spine is a common, early feature and possibly the most frequent first manifestation of disease. Therefore, its early detection is important, and magnetic resonance imaging has proven useful in this regard. To optimize diagnostic accuracy of early disease, it is crucial to use a comprehensive approach and have a deep understanding of the disease and its clinical picture. The clinician should gather a complete history, paying close attention to all the elements of this multisystem disease, as well as judiciously ordering laboratory testing and imaging. New strategies are being developed to assist primary care physicians in their screening for these patients, which in turn should result in early referral to rheumatologists and early diagnosis.

Adult↗
PubMed1994

[CA 15-3 and breast cancer].

The precise clinical value of CA 15-3 antigen has yet to be determined. With no role in screening for early breast cancer and, even if CA 15-3 seems to be correlated with bulky initial tumor burden, it appears to have no independent prognostic value. The clinical interest of CA 15-3 remains the early detection of the first recurrence. In this regard, more than 75% of first recurrences (all sites included) are associated with a significant rise in CA 15-3 levels, with a particular sensitivity for bone, liver, and lung metastases but which appears lower for locoregional recurrences. More sensitive and specific than CEA, and this whatever the site of recurrence, the rise of CA 15-3 may precede the clinically or radiologically diagnostic of recurrence by a mean lead time from 6 to 9 months. Furthermore CA 15-3 is a reliable marker for clinical course and seems to be of potential interest in monitoring disease follow-up during therapy. In the situation of a clinically isolated elevation of CA 15-3, which investigations, if any, have to be done?, and if negative must do we initiate a treatment for a "biological recurrence"? All these questions remain still opened, and today on consensual attitude can be recommended. In this issue, only results of well-designed prospective trials could help us to determine more rationally, an optimal diagnostic and therapeutic strategy.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1975

Applications of diagnostic ultrasound and radionuclides to cardiovascular diagnosis. Part I. Acquired cardiovascular disease in the adult.

Noninvasive methods have become an important part of the diagnostic process for evaluation of cardiovascular anatomy and function in adults and in the young. Because there is a multiplicity of noninvasive methods presently available, in some cases with overlapping capabilities, there has been some confusion as to which constitutes the method of choice in a given clinical circumstance. The reviews that follow outline some of the practical strengths and limitations of two methods (echocardiography and radionuclide cardiography), hopefully thereby providing some rationale for choosing the more appropriate technique in the approach to specific clinical problems. We have found that the information available from radionuclide and from ultrasound studies frequently is complementary and that the most optimal diagnostic results often are obtained when they are combined. Since advances in technique and improvements in instrumentation are occurring continually in both of these areas, we have tried to provide only an overview. Further investigations and clinical experience will help to define the specificity, sensitivity, and capabilities of these methods in terms of present and future applications.

Aortic Valve Insufficiency↗
PubMed1999

Fluoroscopic landmarks for optimal visualization of the proximal renal arteries.

PURPOSE: To accurately determine the in vivo orientation of the origin of the renal arteries from the aorta relative to a fluoroscopic bony landmark for optimal diagnostic arteriography and renal artery stent placement. MATERIALS AND METHODS: One hundred sixty abdominal computed tomography (CT) scans of patients in eight age groups (20-90 years) were reviewed to determine the angle of the origins of the renal arteries from the aorta relative to the long axis of the L-1 spinous process (L1SP). RESULTS: The right renal artery arises ventrally at an angle of 30 degrees (standard deviation [SD] = 15 degrees) from a plane orthogonal to the long axis of the L1SP. The left renal artery arises dorsally at an angle of 7 degrees (SD = 13 degrees) relative to the same plane. CONCLUSIONS: The optimal initial angle for angiographic evaluation of the origin of the renal artery and for renal artery stent placement is 30 degrees left anterior oblique (LAO) relative to the L1SP for the right renal artery and 7 degrees LAO for the left renal artery. Unfortunately, there is variability in the angle of the renal artery origins from the aorta which cannot be controlled for using this technique. In some patients, additional views will be necessary to optimally depict the origins of the renal arteries.

Adult↗
PubMed2000

[Acute headache--diagnostic considerations].

Acute headache may be the presenting symptom of several conditions. Sometimes, a headache with an abrupt onset and unusual severity may occur, experienced by the patient as the worst headache ever. The diagnostic evaluation primarily aims at ruling out subarachnoid haemorrhage (SAH), as well as other serious causes of acute headache, such as meningitis or stroke. The clinical examination should immediately be followed by cerebral computed tomography (CT). A CT scan will reveal 95% of SAHs, provided that it is performed within the first 24 hours after headache onset. If the CT scan is normal, a lumbar puncture should follow, preferably 12 hours after the onset of headache, unless infectious meningitis is suspected. If infectious meningitis is strongly suspected, lumbar puncture should be performed without delay. The spinal fluid should be investigated by spectrophotometry, in order to obtain optimal diagnostic accuracy for SAH. This article briefly reviews the various conditions that may present with an acute headache.

Acute Disease↗
PubMed1997

Noninvasive determination of liver collagen content in chronic hepatitis. Multivariate regression modeling with blood chemical parameters as variables.

To evaluate the diagnostic utility of blood biochemical parameters in assessing degree of hepatic fibrosis, serum levels of aminoterminal type III procollagen peptide (P III P), type IV collagen (IV-collagen), 7S domain of type IV collagen (7S-collagen), and hyaluronan (HA) were measured in 54 patients with chronic viral liver disease. Liver collagen content was quantified by a computer-assisted image analysis method. Significant correlations were found between the amount of collagen in the liver and serum levels of P III P (r = 0.482; P < 0.02), IV-collagen (r = 0.705; P < 0.001), 7S-collagen (r = 0.771; P < 0.001), and HA (r = 0.595; P < 0.001). To optimize diagnostic efficacy, we applied multivariate regression analysis to the combined results obtained for these blood biochemical parameters and some additional laboratory tests. The correlation coefficient obtained from the application of this model was 0.809. To measure the predictive value of the proposed model, we used it to estimate collagen content in an additional 16 patients with chronic liver disease and compared the estimated to the actual amount of collagen determined by direct measurement. The correlation coefficient was 0.937. These results suggest that application of the model would be useful for the assessment of collagen content of fibrotic liver.

Adult↗
PubMed2006

Venous thromboembolic disease: a single-centre case series study.

AIM: The epidemiology of venous thromboembolism in children has likely changed since first being described a decade ago because of evolving management strategies and a greater awareness of predisposing factors for thrombosis in children. The Royal Children's Hospital commenced a 4-year prospective registry of venous thrombosis in 1999 to determine the current Australian epidemiology of venous thrombosis in infants and children. METHODS: A prospective, single-centre registry was established to determine the prevalence, aetiology, diagnostic criteria, management and outcome of venous thromboembolism in an Australian tertiary paediatric centre. RESULTS: The incidence of venous thrombosis was 8.0/10 000 hospital admissions. Fifty-eight per cent of infants and 49% of children were male. Seventy-seven per cent of venous thromboses in infants were associated with central venous cannulation compared with 47% in children. Doppler ultrasonography was the most frequently used diagnostic tool. Treatment strategies varied between age groups. The all-cause mortality rate for infants and children in this study was 8.4% (direct thrombus-related mortality 0%). Fifteen per cent of all patients demonstrated complete resolution of their venous thrombosis at discharge, with 48% demonstrating complete resolution at follow-up assessment. Fifteen per cent of patients experienced significant thrombosis-related morbidity at follow-up assessment. CONCLUSION: In this single-centre registry, venous thrombosis in infants and children occurred with greater frequency than has previously been reported and its epidemiology varied. Central venous catheterisation continues to be a common precipitant to venous thrombosis. Optimal diagnostic and treatment interventions for venous thromboembolism have not yet been determined for infants and children, despite the significant incidence of long-term sequelae.

Adolescent↗
PubMed2000

[Diagnostic and therapeutic consequences of kidney injuries in pediatric blunt abdominal trauma].

Renal lesions are frequently encountered in blunt pediatric abdominal trauma. In this retrospective study, we analyzed the incidence of renal trauma in these trauma patients to determine which diagnostic and therapeutic approaches were most predictive. From 1976 to 1996, 308 children sustaining blunt abdominal trauma were admitted to our department. Patients were evaluated using abdominal paracentesis, ultrasonography, and urinary analysis. In specific cases, i.v. urography, CT scan, and/or angiography were applied. We used the Organ Injury Scale (OIS) for classification of renal trauma into five grades. We encountered 69 serious abdominal traumas. Thirty-six patients sustained renal lesions grade 2 (G2) or higher; 20 children were polytraumatized. There were 67 renal lesions with 28 G1, 22 G2, 8 G3, 5 G4, 1 G5, and 3 lesions of the urinary tract. Ultrasonography and urinary analysis were found to be optimal diagnostic means for screening and observing the course of renal lesions. For lesions G2 or higher, CT scan was the most reliable in classifying and diagnosing renal lesions. This superseded i.v. urography. If no contrast medium was excreted in the CT scan, angiography was indicated. Only ten patients proceeded to operative therapy. During the period reviewed, a shift from operative to conservative treatment was notable with a tendency toward minimally invasive therapy. If lesions were G4 or G5, operative treatment was always indicated.

Abdominal Injuries↗
PubMed1992

Small bronchogenic carcinomas presenting as solitary pulmonary nodules. Bioptic approach guided by CT-positive bronchus sign.

To evaluate the utility of the CT bronchus sign in making a choice between transbronchial biopsy (TBB) and transthoracic needle aspiration (TTNA) as the first diagnostic procedure in a patient with a solitary pulmonary nodule (SPN), we reviewed the results of TBB and TTNA in 26 patients who had a bronchogenic carcinoma less than 3 cm, studied with thin-section CT. The patients were divided into two groups. Group 1 included ten cases with a third- to fifth-order bronchus sign. Group 2 included two cases with a sixth-order bronchus sign and 14 cases with absence of a bronchus sign. TBB was performed in all the patients; conversely, TTNA was carried out in 22 patients. In group 1, TBB gave a diagnostic yield in eight (80 percent) of ten patients, while TTNA was positive in three (42 percent) of seven patients (p > 0.05). Conversely, in group 2, results of TBB were normal in all the patients, while TTNA gave a diagnosis in 10 (66 percent) of 15 patients (p < 0.05). We think that TBB should be considered the method of choice in diagnosing SPNs associated with a third- to fifth-order bronchus sign; conversely, TTNA is more useful than TBB in diagnosing SPNs in the presence of a more peripheral bronchus sign or with the absence of a bronchus sign. In conclusion, we suggest routine evaluation with thin-section CT of each SPN to optimize diagnostic management.

Biopsy, Needle↗
PubMed2001

Evaluation of serologic disease markers in a population-based cohort of patients with ulcerative colitis and Crohn's disease.

BACKGROUND: The sensitivity of assays for antineutrophil cytoplasmic antibody (ANCA), anti-Saccharomyces cerevisiae antibody (ASCA), and antipancreatic antibody (PAB) in different laboratories is unknown. Likewise, the sensitivity and diagnostic usefulness of these assays in patients with inflammatory bowel disease (IBD) in the community is unknown. METHODS: An incidence cohort of 290 patients with IBD were offered participation in the study. Blood was obtained from 162 patients (56%) (83 with ulcerative colitis, 79 with Crohn's disease) who agreed to participate. ANCA was determined in five laboratories. ASCA in two laboratories, and PAB in one laboratory. RESULTS: In ulcerative colitis, the sensitivity of ANCA determined in five laboratories varied widely, ranging from 0-63%. In Crohn's disease, the sensitivity of ASCA determined in two laboratories did not vary significantly, ranging from 39-44%; and the sensitivity of PAB determined in one laboratory was 15%. The optimal diagnostic usefulness was obtained from one laboratory where the positive predictive values of a positive ANCA assay combined with a negative ASCA assay for ulcerative colitis, and a negative ANCA combined with a positive ASCA for Crohn's disease, were 75% and 86%, respectively. CONCLUSIONS: In patients with IBD, the sensitivity of ANCA varied widely in different laboratories, whereas the prevalence of ASCA was similar. The positive predictive values of the ANCA assay combined with the ASCA assay for ulcerative colitis and Crohn's disease are high enough to be clinically useful.

Adolescent↗
PubMed1998

Effect of operationalized computer diagnosis on the therapeutic results of sumatriptan in general practice.

A multicenter test was conducted to investigate the effectiveness of the selective serotonin agonist sumatriptan in patients with the computerized headache diagnosis of migraine. A computer program was used for diagnostic evaluation of patients attending a general practice because of headache. The results of the analysis were taken as a direct decision on therapy. If the patients satisfied the criteria for migraine, they were given subcutaneous sumatriptan for treating three migraine attacks. The patients were able to use the study medication under outpatient conditions. The therapeutic efficacy of the medicine was recorded in a headache diary. A total of 91 patients were included in the study at 22 practices in Germany. An average of four patients per practice were recruited. In the first migraine attack treated, headache improvement was experienced by 77.7% of the patients treated. In the second and third attacks an improvement was experienced by 93.5% and 89.8%, respectively. The results show that by optimizing diagnostic reliability with the aid of the computer program a high response rate can be achieved under practice conditions using the selective serotonin agonist sumatriptan. Since the computer program described permits a specific diagnosis, it improves the prospects of effective headache therapy in the individual patient. Thus treatment based on this approach can reduce inputs of time and money in migraine therapy.

Adolescent↗