PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “diagnostic methods”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources

[Diagnostic methods for fetal malformations in the first half of pregnancy].

INTRODUCTION: Fetal abnormalities are the most common cause of perinatal and postnatal death and infant handicap. For this reason prenatal screening (for fetal malformation) has become a routine part of obstetric care in many countries. Most often used are biochemical tests and continuously developing ultrasound diagnostics which makes possible precise analysis of the fetal morphology. There is interesting to establish a noninvasive test for the early detection of fetal malformation in pregnancy which is based on ultrasound examination (NT measurement from the 10th to the 19th weeks, presence of nasal bone in the first trimester ultrasound), correlated with serum concentration of AFP, beta-HCG and oestriol in the second trimester of pregnancy (triple test). The main aim of the study was to establish a diagnostic schema for detection of fetal malformations based on NT measurement in the first and second trimester coupled with triple test performed in the second trimester. MATERIALS AND METHODS: A group of 775 pregnant women from the 10-th week of pregnancy until childbirth has been put under examination. Between the 10th and the 14th and than between 15th and 19th week of pregnancy ultrasound examination with fetal biometry and NT measurement was done. NT measurements have been performed in accordance with the standards worked out by professor K. Nicolaides. At the first ultrasound examination the presence of the nasal bone was observed. The next step was performing the triple test between the 15th and 19th week of pregnancy. On the same day as second ultrasound examination blood was taken to determine the results of the triple test (ELISA method). The obtained results have undergone statistical analysis. RESULTS: The age of women qualified for the examination oscillated between 15 and 45 (over 35 -9.4%). There were 8 fetal malformations recognized all connected with the chromosomal anomalies, namely, 4 Downs syndrome, 2 fetuses with trisomy of the 18th pair of chromosomes and 2 with triploidy. At all physiologic pregnancies nasal bone was seen during first ultrasound examination. The obtained results of nuchal fold measurements and concentrations for the parameters of the triple test have been the basis to calculate medians in the particular weeks of pregnancy. In all the cases of genetic malformations the widening of the nuchal fold above 99 percentile (MoM NT) has been observed. Fetal nasal bone were absent in 62.5% first trimester ultrasound examinations. The risk of the occurrence of a genetic malformation resulting from the mother's age combined with the risk connected with the NT measurements and the results of the triple test for the cut-off point 1:250 (which seems to be the best for this population) gave 100% sensitivity, 0.6% % of false positive results and the positive predictive value of 80%. The above mentioned results are better than the ones which were obtained within the triple test only, where for the previously fixed cut-off point 1:250 sensitivity reached 63%, positive predictive value 25% and 4.4% false positive rate. Performing the so-called integrated test in which the risk of the occurrence of any malformation is estimated on the basis of the NT measurement in the first and the second term of pregnancy seems to be far more useful. CONCLUSIONS: Diagnostic schema for detection of fetal malformations in the first half of pregnancy which is based on ultrasound examination (NT measurement from the 10th to the 19th weeks), correlated with serum concentration of AFP, beta-HCG and oestriol in the second trimester of pregnancy (triple test) is very sensitive and safe method of the prenatal diagnosis leading to significant decrease of the invasive procedures (amniocentesis).

Abnormalities, Multiple↗

[Comparative assessment of diagnostic methods in adenomas of the thyroid gland].

The authors carried out comparative assessment of sensitivity and specificity of ultrasonic examination with color dopper mapping (USE with CDM), thin-needle aspiration biopsy--TAB (palpation- and US-assisted), express histologic examination--(EHE), intraoperative laser autofluorescent spectroscopy (IOLAS) with retrospective assessment by results of elective histologic examination in adenomas of thyroid gland (TG). Medical histories of 135 patients hospitalized with adenomas of TG of follicular cells were analyzed. Based on comparison of USE with CDM and morphologic analysis of TG adenomas three types of specific echographic symptomcomplexes were recognized. USE with CDM in combination with US-assisted TAB was the most effective diagnostic complex before operation. Comparative analysis of results of these methods with express histologic examination showed equal efficacy, that permitted to reject routene EHE. For the first time IOLAS was used as "optic instant-biopsy" for selection of optimum scope of surgery when "follicular neoplasia" was suspected. Combined use of USE with CDM and TAB before operation as well as IOLAS enabled correct diagnosis of the nature of TG lesion, it morphologic type, and based on these data adegnatechoice.

Adenoma↗

Quantitative diagnostic methods in osteoporosis: a review.

During the last two decades there have been major advances in the understanding of pathophysiology and in the diagnosis of osteoporosis. There are now, in addition to standard radiographs, a number of different diagnostic modalities available to doctors for the quantitative assessment of bone mass. These methodologies are having an increasingly important role, not only in the clinical diagnosis, but also in the monitoring of patients with osteoporosis. As the population ages there will be an increasing demand for these services, and radiologists need to be aware of the strength and limitations of the different modalities available.

Absorptiometry, Photon↗

[Cerebral findings following cervical spine distortion caused by acceleration mechanism (whiplash injury). Assessment of current diagnostic methods in nuclear medicine].

In any grade of distortion of the cervical spine as a result of acceleration forces in addition to cervical symptoms cerebral symptoms like headache, vertigo, auditory disturbances, tinnitus, disturbances in concentration and memory, difficulties in swallowing, impaired vision and temporo-mandibular dysfunctions may appear. These symptoms can persist and become invalidating. Cerebral single-photon emission tomography (SPECT) and positron emission tomography (PET) enable new diagnostic horizons for neurotraumatology. In this article we summarize the actual findings of these nuclear medical methods in neuropsychologically deficient patients with distortion of the cervical spine as a result of acceleration forces. Especially the latest results of the group of Basle (University Hospital Basle, Clinic of Rehabilitation Rheinfelden, Switzerland) are illustrated. This group found parieto-occipital hypoperfusion by relative quantitation using SPECT and bicisate (Neurolite, ECD). A first pilot study using PET and F-18-fluoro-deoxyglucose (FDG) could verify the above observation. The group's working hypothesis is that parieto-occipital hypoperfusion may be caused by activation of nociceptive afferences from the upper cervical spine. A critical approach to interpreting new functional methods and, on the other hand, openness in new scientific findings may contribute to answering the lasting controversial medico-legal discussion with more objectivity.

Brain↗

Mesenteric vascular disease: a review of diagnostic methods and therapies.

Mesenteric vascular disease is a relatively rare disease; however the morbidity and mortality are significant. Improved diagnosis and treatment of mesenteric obstructive arterial disease and its complications have occurred. Biplanar angiography of the mesenteric arteries remains the best method of diagnosing mesenteric vascular diseases, though duplex sonography of the mesenteric arteries appears to be a valuable screening tool. Magnetic resonance angiography has the potential to improve on the diagnostic accuracy. Mesenteric artery reconstructive surgery remains the treatment of choice. Newer surveillance techniques such as tonometry may enhance perioperative monitoring and consequently improve the results of mesenteric artery reconstructive surgery. Aggressive support medical therapy plays a significant role in the treatment and reduces patient morbidity and mortality in carefully selected cases. There remains a dearth of prospective controlled trials in patients with this condition.

Angiography↗

The evaluation of the common diagnostic methods of hypersensitivity for bee and yellow jacket venom by means of an in-hospital insect sting.

Between 1979 and 1983 230 patients visited our clinic in connection with allergic reactions after insect stings. One hundred six patients were subjected to a diagnostic provocation test with a live insect; 86 of these patients had a history of systemic reactions and a positive skin test and RAST with insect venom. Thirty-one of these patients, including one patient with a negative RAST and another with a negative skin test, demonstrated a generalized reaction and were subjected to immunotherapy with pure insect venom. Comparison of the diagnostic data from 31 patients with reactions with those of the 57 nonreacting patients from the 86 patients aforementioned reveals that at this time only a provocation test with a live insect can provide the evidence of an allergy to insect venom leading to such a severe generalized reaction that admission to probably lifelong immunotherapy is justified. The measurement of the venom-specific IgG, the ratio of IgG/IgE, and (for bee patients) the serum antibody titer against the bee venom components phospholipase A and hyaluronidase did not improve the diagnosis of a current hypersensitivity against insect venom.

Adolescent↗

Diagnostic methods for Chlamydia trachomatis disease in neonates.

Chlamydia trachomatis is an obligate intracellular parasite responsible for many clinical syndromes, including neonatal conjunctivitis and pneumonia. The gold standard of diagnosis has been isolation in cell culture. However, this requires days of processing. Several rapid diagnostic tests are available. Giemsa staining of conjunctival smears, enzyme immunoassay, and the fluorescein-conjugated monoclonal antibody test. Both the EIA and the FA tests show promise as ideal rapid diagnostic tests. Treatment of chlamydial conjunctivitis must focus upon the eradication of nasopharyngeal carriage as well as cure of ophthalmic symptoms. The need for nasopharyngeal eradication is underscored by the fact that it is the source for chlamydial pneumonia as well as for conjunctival re-infection. Clinical studies have shown that oral erythromycin estolate or ethylsuccinate suspension 50 mg/kg/day twice-daily or four times a day for 14 to 21 days are the therapeutic regimens of choice. Neonatal ocular prophylaxis is currently under study. One per cent silver nitrate does not prevent chlamydial conjunctivitis but preliminary studies do show favorable results with topical erythromycin. Nevertheless, neither 1 per cent silver nitrate nor topical erythromycin eradicate nasopharyngeal carriage, elimination of which is necessary for the prevention of neonatal chlamydial pneumonia.

Conjunctivitis, Inclusion↗

[New possibilities of radiologic diagnostic methods for diseases of the spinal column using spinal computer tomography].

During the last there years (from May 1981 to March 1984) we performed 1368 CT examinations of the spine, 447 of the cervical, 264 of the thoracic and 657 of the lumbar vertebral column. 30% of the CT examination of the lumbar spine revealed a prolapse of an intervertebral disk. In 38% of the cases involving the thoracic spine metastases were seen. We diagnosed fractures in 10% of the cervical spine and 11% of the thoracic spine examinations. Posttraumatic or postoperative intravertebral haemorrhage was hardly ever diagnosed in our patients (1.9% of the cases). Spinal trauma: The anterior-posterior and lateral plain films continue to be the mainstay of radiographic screening in spinal injury. Nevertheless, the degree of injury is underestimated in a significant number of patients with spinal trauma if conventional radiography is the only diagnostic approach. For further clarification CT proved to be the fastest and best method to recognise the causes and extent of compression of the vertebral canal. CT has attained a high degree of accuracy in the diagnosis of prolapse of intervertebral disks, replacing myelography if the findings are unequivocally established. CT should also be preferred to myelography in suspected recurrent prolapse. Localisation, shape and density are criteria for differentiating between scarification and prolapse via CT. The results show that CT has opened up new possibilities in the diagnosis of spinal diseases and has resulted in a reorientation of the diagnostic approach.

Humans↗

Diagnostic methods for deep vein thrombosis.

Clinical diagnosis of deep vein thrombosis (DVT) is unreliable, and treatment should not be undertaken without objective confirmation. The traditional 'gold standard' for the diagnosis of DVT has been venography, but ultrasonic imaging has now replaced venography as the new diagnostic standard in many hospitals. A variety of noninvasive physiologic tests are also useful in selected circumstances. These include plethysmography, Doppler flow studies, radioisotope tests, thermography and peripheral blood tests which reflect activation of coagulation or thrombolysis. We describe the clinical application of these diagnostic procedures, both for symptomatic patients suspected to have DVT and for asymptomatic patients at high risk for DVT. The selection of an appropriate diagnostic modality depends upon institutional capabilities, cost-effectiveness and individual patient circumstances.

Computer Systems↗

[Application of interdisciplinary collaboration, new diagnostic methods and therapeutic procedures in dental surgery].

The authors, based on their own experience, draw attention to the necessity of interdisciplinary collaboration in the diagnosis and treatment of patients who need a surgical operation in the orofacial and craniofacial region. They draw attention to new diagnostic and therapeutic procedures and possibilities, and to the advantages of computer technique and the part played by microelectronics in stomato-surgical practice.

Computer Systems↗

[Culture based diagnostic methods for tuberculosis].

Culture methods providing isolates for identification and drug susceptibility testing, still represent the gold standard for the definitive diagnosis of tuberculosis, although the delay in obtaining results still remains a problem. Traditional solid media are recommended for use along with liquid media in primary isolation of mycobacteria. At present, a number of elaborate culture systems are available commercially. They range from simple bottles and tubes such as MGIT (BD Diagnostic Systems, USA), Septi-Chek AFB (BD, USA) and MB Redox (Biotest Diagnostics, USA) to semiautomated system (BACTEC 460TB, BD, USA) and fully automated systems (BACTEC 9000 MB [BD, USA], BACTEC MGIT 960 [BD, USA], ESP Culture System II [Trek Diagnostics, USA], MB/BacT ALERT 3D System [BioMérieux, NC], TK Culture System [Salubris Inc, Turkey]). Culture methods available today are sufficient to permit laboratories to develop an algoritm that is optimal for patients and administrative needs. In this review article, the culture systems used for the diagnosis of tuberculosis, their mechanisms, advantages and disadvantages have been discussed under the light of recent literature.

Algorithms↗

The integration of molecular diagnostic methods into the clinical laboratory.

Since the advent of the polymerase chain reaction in the mid-1980s, molecular diagnosis has become an important component of the services offered by many clinical laboratories. This presentation reviews selected applications of molecular methods in various sections and specialties of the clinical laboratory, and assesses the intellectual and technical qualifications and resources that traditional clinical laboratories can bring, and are bringing, to performance of molecular diagnostic tests. Special requirements for performance of molecular assays, in terms of both technical matters and clinical approaches, are also considered. Finally, attention is given to several contemporary factors that are tending to slow growth of molecular diagnosis in the clinical laboratory, and to other factors that are having a contrary effect, tending to promote growth in this area. A decision by an individual laboratory concerning the extent of its participation in molecular diagnosis should be based on recognition of the essential requirements for satisfactory performance of molecular testing, and a realistic appraisal of the laboratory's ability to meet these requirements.

Clinical Laboratory Techniques↗

A user's inter-laboratory comparison of broodfish screening for infectious pancreatic necrosis virus using molecular and conventional diagnostic methods.

Individual testing and subsequent removal of eggs from infectious pancreatic necrosis virus (IPNV)-positive parents is required for export of salmonid eggs to some farming countries. Testing by cell culture requires more than three weeks before the eggs can be released from quarantine and incurs significant logistic problems and costs. The feasibility of the RT-PCR testing method as offered by several laboratories was therefore evaluated during the current inter-laboratory comparison study. Frozen kidney sub-samples from 100 motherfish of Atlantic salmon (Salmo salar L.) were shipped to three diagnostic laboratories (A, B and C) for testing by RT-PCR and cell culture. Of the 100 examined samples, all proved IPNV-negative by cell culture. Thirty samples were positive by RT-PCR analyses, but only four of these samples were RT-PCR positive in two laboratories and none in any of the three laboratories. From a disease management point of view, the RT-PCR test outcomes gave no reasonable guidance as to which fish were truly infected and which batches of fertilised eggs should be discarded. This is clearly an unacceptable situation and calls for new research to standardise sample conservation, RNA extraction procedures and amplification techniques, to estimate method sensitivity and specificity, and to validate the method's performance and robustness to support disease control measures in salmonid aquaculture.

Animals↗

[Bronchoalveolar lavage--a diagnostic method in chronic nonspecific bronchopulmonary diseases in childhood? 2. Studies of cellular and humoral parameters in BAL irrigation fluid].

With a view of the pathogenesis of chronic bronchopulmonary diseases the interrelations between infections and evolving defense system are of interest, they are perhaps detectable by means of diagnostic bronchoalveolar lavage. We carried out cytodifferentiation, investigated adenosine deaminase activities and interleukin 1 formation of macrophages, determined immunoglobulin concentrations (secretory IgA), lysozyme, alpha 2-macroglobulin, alpha 1-antitrypsin, albumin. Because the cytodifferentiation yields insight into topical inflammatory reactions, shows diagnostic useful informations in single cases and because it is simple to carry out we can recommend it for each bronchological examination. There were no results specific for any disease group for parameters mentioned above.

Adenosine Deaminase↗