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At least 1,693 records · Page 94Linked to original sources
PubMed1987

Rapid methods for the molecular diagnosis of infectious diseases: current trends and applications.

Methods for the rapid diagnosis of infectious diseases have become increasingly common in the last decade. The impetus for the development of such techniques has stemmed from the need to provide clinically relevant information without the length of time and complexity inherent to traditional cultivation methods. This is particularly important in high-risk populations for which more effective antibiotics and antiviral compounds are now available. Assay systems for the immunological detection of microbial agents occupy a central role in the molecular diagnosis of infectious diseases and are rapidly appearing on the market. Novel methods of organism detection by nucleic acid hybridization, long considered usable only in highly specialized laboratories, have the potential for use in routine microbiological laboratories and some systems are now commercially available. As more efficient and rapid diagnostics systems are being developed, the selection of the optimal method will depend on the environment in which the system is to be used. Rapid methods for the detection of infectious agents might markedly improve health care in a variety of clinical, laboratory and epidemiologic situations.

Agglutination Tests↗
PubMed1997

Hydro-CT in patients with gastric cancer: preoperative radiologic staging.

A total of 35 patients (age range 35-78 years) with gastric tumors on the lesser curve, or in the antro-pyloric region, underwent angio-CT in the prone position after filling the stomach with 500 ml of water and intravenous administration of glucagon. The films were reviewed by three radiologists independently, staging each tumor according to the TNM classification preoperatively. The overall accuracy of tumor staging ranged between 66-77 %, overstaging between 17-25 %, and understaging between 3-8.5 %. The diagnostic sensitivity, specificity, and accuracy for serosal invasion ranged between 90 and 100, 76 and 84, and 80-88 %, respectively, and the overall accuracy for N staging was 46, 48, and 51 % for the three observers. If, however, N1 and N2 tumors were considered as a single group, N-stage accuracy increased, ranging between 63 and 77 %. The "K test" for analyzing the interobserver agreement was 60 %, i. e., the diagnostic results are reproducible. Water filling of the stomach optimizes visualization of the gastric wall on contrast-enhanced CT. The prone position and drug-induced hypotony allows for good distension without any disturbing artifact reduction obscuring the lower gastric body.

Adult↗
PubMed2000

Volume measurement of cerebral arteriovenous malformations from angiography.

We designed software for measuring the volume of cerebral arteriovenous malformations from angiography and validated it against prescription volumes in radiosurgery. We aimed to create a model for the risk for complications as a function of volume, based on established outcome prediction models for Gamma Knife radiosurgery, but without the need for dose planning. We created an application for computing the volume of cerebral arteriovenous malformations from the intersection of two X-ray cones in stereotactic space. Volume measurements were compared with prescription volumes from dose planning, in phantoms and in patients treated with Gamma Knife radiosurgery for cerebral arteriovenous malformations. Previous studies of 1128 treated patients were used to calculate the risk for complication as a function of the nidus volume. In 63 patients volumes measured with either method correlated, R2 = 0.85. Volume as measured with the intersecting cone model (ICM) correlated with predicted Gamma Knife radiosurgery complication rate, R2 = 0.84. The ICM can thus be used for measurement of AVM volumes less than 10 cm3 from angiography. Outcome models from Gamma Knife radiosurgery may be applied, but with reduced exactness. Standardised AVM volume measurement is valuable for comparing outcome and for quantification of volume reduction after therapy, notably embolisation. Thus the optimal management plan may be selected in conjunction with diagnostic or therapeutic angiography.

Cerebral Angiography↗
PubMedDate not supplied

Frequency of arteriovenous shunts in hepatic cavernous hemangiomas in adults as seen on selective arteriography and postembolization radiography.

PURPOSE: To study the frequency and angiographic findings of arteriovenous shunts (AVS) associated with adult cavernous hemangiomas of the liver (CHL) on hepatic artery digital subtraction angiography (DSA) and optimize the imaging technique of DSA to improve its diagnostic efficacy. METHODS: We retrospectively analyzed 43 intraarterial DSA procedures performed on 30 adults with CHL. Of the 30 patients 22 were found to have an AVS. Transcatheter arterial embolization with Lipiodol (L-TAE) was performed on 21 of these and radiographs were taken immediately after embolization to observe the distribution of the injected iodized oil. The results were compared with those of the AVS found on DSA images. RESULTS: AVS were identified by DSA in 22 (73.3%) of 30 patients. All AVS were located in the peritumoral liver tissue and had a parallel track appearance, or early filling of small draining veins during the arterial phase of DSA. Radiographs taken immediately after L-TAE in 21 of the 22 cases with AVS showed iodized oil filling a few portal branches or draining veins as a result of incompletely occluded shunts in 11 patients. In 10 patients there was complete occlusion and no filling of any vein, or only the originating end of draining veins filled with iodized oil. No evidence of AVS was found in the other eight patients in this series, and in six of these the DSA was not considered diagnostic. CONCLUSION: The present study indicates that AVS are frequently seen in adults with CHL. DSA with high-quality images is helpful in identifying small AVS of CHL. The formation of an AVS in CHL may be closely related to the pathological changes in the peritumoral liver tissue.

Adult↗
PubMed1999

Endometrial polyps. A clinical study of 245 cases.

OBJECTIVES: Endometrial polyps (EPs) are among the common cases of abnormal uterine bleeding. Hormonal factors may be involved in the pathogenesis as indicated by endometrial abnormalities in patients treated with tamoxifen. This study was designed to analyse the patient characteristics which may be associated with polyp occurrence and assess the diagnostic and therapeutic difficulties. Group of 245 patients was formed to 152 postmenopausal and 93 premenopausal women with EP diagnosed hysteroscopically and confirmed histologically. Evaluated factors were as follows: 1) patient characteristics: age, body mass, systemic hypertension, diabetes mellitus, nulliparity, late menopause, estrogen replacement therapy, and tamoxifen treatment; 2) clinical features of EPs, and 3) the number of curettage's (D & C) and hysteroscopies. RESULTS: Hypertension associated with obesity appears to be an important factor in combination which may play role in the pathogenesis of EPs like the late menopause which was noted in 30% of examined postmenopausal women. An association between EPs and tamoxifen was found in 8% patients with breast cancer. 2. Postmenopausal uterine bleeding and menstrual disorders were prominent clinical symptoms in 44% post- and in 82% of premenopausal women. The other 56% post- and 18% premenopausal patients were asymptomatic. 3. The multiple EPs were present in 26% of postmenopausal and in 15% premenopausal women. 4. Transvaginal ultrasonography supplemented by sonohysterography in cases with abnormal ultrasonographic findings should be the main diagnostic method. 5 Hysteroscopical polypectomy is regarded as the optimal therapy and the removal of the endometrial basalis in the EP origin area prevents persistence or recurrence of EP.

Adult↗
PubMed2004

Laser projection in high-speed glottography for high-precision measurements of laryngeal dimensions and dynamics.

The detection of metric dimensions of laryngeal structures yields valuable information for both clinical and research purposes. The use of a laser projection system combined with a high-speed camera system enables the derivation of absolute spatial dimensions of the larynx. Vocal fold length, vibratory amplitudes and velocity can be derived. This was shown on 13 female and 9 male larynges during phonation of a vowel at different pitches. The vocal fold length, the amplitude of oscillation and the velocity of vibration were analyzed in between pitches of 119 to 236 Hz in the male group and 181 to 555 Hz in the female group. The vocal folds' length ranged from 8.4 to 14.3 mm in the male group and from 7.7 to 15.6 mm in the female group. Corresponding amplitudes varied from 0.33 to 1.24 mm (male) and from 0.38 to 0.82 mm (female). The maximal velocity of vibration was between 0.48 and 0.85 m/s in males and between 0.47 and 1.3 m/s in females without showing significant correlation between each parameter. The described technique enables the detection of absolute spatial laryngeal dimensions of female and male subjects at different pitches. Dynamic processes such as velocity of vibration can be quantified. The detection of metric data serves to optimize biomechanical model computations and provides valuable information in diagnostics and interpretation of organic and non-organic voice disorders.

Adult↗
PubMed2000

Intracavernous sinus ectopic adrenocorticotropin-secreting tumours causing therapeutic failure in transsphenoidal surgery for Cushing's disease.

BACKGROUND: The major cause of surgical failure in the treatment of Cushing's disease lies in unsuccessful identification of adenomas. In the present study, we investigated the pathogenesis of negative exploration in transsphenoidal surgery for Cushing's disease by analyzing neuro-imaging studies, endocrinological examination and selective venous sampling. METHODS: Thirty patients with ACTH-dependent Cushing's syndrome that met the endocrinological criteria for Cushing's disease were treated by transsphenoidal microsurgery. Depending on positive or negative identification of adenomas during the surgery, selective adenomectomy, partial hypophysectomy or subtotal hypophysectomy was performed. FINDINGS: All nine patients who underwent selective adenomectomy showed endocrinological remission and did not need any hormone replacement therapy. Of the 12 patients who underwent partial hypophysectomy, 11 showed normalization of hypercortisolism but seven needed permanent replacement of hydrocortisone. Four patients underwent subtotal hypophysectomy because no adenoma could be identified in spite of detailed exploration, and three of them showed remission but with permanent requirements of hydrocortisone and other pituitary hormones. Five patients, whose hypercortisolism persisted after initial surgery, underwent total hypophysectomy as secondary transsphenoidal surgery, and only one of them showed endocrinological remission. Of the six patients with surgical failure, four were thought to be rare cases in whom the ACTH-secreting tumours may have occurred ectopically in the cavernous sinus without direct contact with the pituitary gland. Endocrinologically, these four patients showed a low or no response to corticotropin releasing hormone (CRH) stimulation, and for three of them, radiation therapy to the sellar region including the cavernous sinus was effective for persistent hypercortisolemia. INTERPRETATION: Recognition of an ectopic intracavernous sinus ACTH-secreting tumour as a pathological entity for Cushing's disease may not only enhance the diagnostic accuracy but also be important for determining the optimal surgical mode for persistent Cushing's disease.

Adenoma↗
PubMed2002

Enhanced interfaces for web-based enterprise-wide image distribution.

Modern Web browsers support image distribution with two shortcomings: (1) image grayscale presentation at client workstations is often sub-optimal and generally inconsistent with the presentation state on diagnostic workstations and (2) an Electronic Patient Record (EPR) application usually cannot directly access images with an integrated viewer. We have modified our EPR and our Web-based image-distribution system to allow access to images from within the EPR. In addition, at the client workstation, a grayscale transformation is performed that consists of two components: a client-display-specific component based on the characteristic display function of the class of display system, and a modality-specific transformation that is downloaded with every image. The described techniques have been implemented in our institution and currently support enterprise-wide clinical image distribution. The effectiveness of the techniques is reviewed.

Computer Systems↗
PubMed1992

Medical therapy for gastroesophageal reflux disease.

Gastroesophageal reflux disease (GERD) remains a ubiquitous problem, although therapeutic options continue to evolve. Effective therapy calls for understanding the pathogenesis. Key factors associated with GERD include incompetence of the lower esophageal sphincter, esophageal clearance, gastric contents, tissue resistance, and potency of the refluxate. Phase-type directed therapy remains the best treatment approach and histamine (H2)-receptor antagonists are now the cornerstone of therapy for patients not responsive to conservative measures. In a subset of patients with severe esophagitis who do not respond to conventional H2-receptor antagonist therapy, efficacy has been demonstrated with high-dose therapy. The acid suppressant omeprazole, highly effective in erosive esophagitis, is the drug of choice for esophagitis resistant to H2-receptor antagonists. Despite effective forms of therapy, relapse rates are high in patients with severe GERD, and maintenance therapy typically is required. With near uniformity, efficacy end points for these agents have been directed toward relief of heartburn, regurgitation, and dyspepsia. Few data exist correlating relief of GERD and improvement of chest pain. Although therapeutic strategies for treating GERD have improved, empiric treatment of suspected GERD in the patient with noncardiac chest pain does not appear to be the optimal approach and should be reserved for cases where diagnostic testing is limited or unavailable.

Chest Pain↗
PubMed2005

Treatment planning for multiunit restorations--the use of diagnostic planning to predict implant and esthetic results in patients with congenitally missing teeth.

Patients afflicted with congenitally missing teeth are a unique patient population for consideration of treatment with osseointegrated implants. Frequently, these patients have limited development of the alveolar process and differences in spatial position relative to the opposing arch, which places emphasis on ancillary treatment with orthodontics and oral surgery. A thorough diagnostic workup should include an interdisciplinary approach to ensure optimal treatment and timing of treatment in those who are developing. This article outlines considerations for treating these types of patients and scenarios of treatment paths frequently taken to restore the partially dentate and edentulous to esthetics and function.

Anodontia↗
PubMedDate not supplied

Magnification endoscopy as a reliable tool for the early diagnosis of rejection in living related small bowel transplants: a case report.

The purpose was to determine whether magnification endoscopy (ME) accurately diagnosed rejection in living related small bowel transplants (LRSBTx) during initial morphological adaptation of segmental intestinal grafts. The small bowel recipient was a 44-year-old woman with short gut syndrome following multiple bowel surgeries for familial adenomatous polyposis. ME was enhanced by chromoendoscopy staining. Bowel mucosa was washed with acetic acid and stained with methylene blue for optimal visualization of mucosal villi and to improve the diagnostic yield of biopsies. The recipient underwent surveillance ME with biopsy 16 times through the ileostomy in the first 9 months following transplantation. The recipient developed diarrhea in the postoperative course, which led to the suspicion of rejection. ME findings of patchy villus blunting were consistent with biopsy samples that showed mild acute cellular rejection. Episodes of rejection were treated with high-dose immunosuppressants and steroids. Reversal of rejection was monitored by follow-up ME, which showed increased length of villi and normalization of morphology. Biopsy confirmed these findings. The first endoscopy, at 5 days posttransplant, showed no evidence of intestinal ischemia. LRSBTx involves early morphological adaptation of the recipient small bowel mucosa, characterized by an increased length of villi. ME is a reliable technique to follow adaptation and detect early rejection. The superior imaging of small bowel mucosa created by ME chromoendoscopy enables early diagnosis and delivery of more prompt antirejection therapy to prevent progression of rejection. ME also confirmed that segmental LRSBTx caused minimal ischemic injury to the recipient.

Adenomatous Polyposis Coli↗
PubMed2004

An interlaboratory comparison of immunohistochemistry and PCR methods for detection of Neospora caninum in bovine foetal tissues.

Seven European laboratories contributed to a multi-centre evaluation of detection techniques for Neospora caninum in bovine foetuses. Six laboratories participated in immunohistochemistry (IHC) testing. All seven laboratories participated in PCR testing, but the results from one laboratory were not included in the analysis, because of contamination problems in the preparation of the samples. A coded panel of tissue sections from 36 infected and non-infected foetuses was used to evaluate the IHC detection of parasites. A coded panel consisting of 44 homogenized foetal brain samples from natural bovine abortion cases and 32 spiked samples were used to evaluate the PCR methods. Inclusion of a duplicate dilution series of spiked samples was used to evaluate detection limits and repeatability. IHC methods had a relatively low sensitivity, but a high specificity. There was considerable variation in IHC results between participating laboratories, which may be partly explained by examination practices that depended on the experience of the operator. In addition, the use of different antibody reagents, different antibody dilutions, and different enzymatic treatments of tissues may have contributed to the observed variation. PCR methods generally had a higher sensitivity than IHC methods and also a high specificity. The agreement between the majority scores of IHC and PCR methods was low. False positive PCR results indicated contamination problems in some instances. Agreement between the PCR results of the various laboratories was better, compared with the IHC results. There appeared to be no clear relationship between the PCR format (i.e. single or nested) and diagnostic sensitivity. Consequently, an improvement of diagnostic performance of PCR might possibly be achieved by optimizing DNA extraction methods.

Abortion, Veterinary↗
PubMed2003

Pathology of malignant melanoma.

Understanding the fundamental aspects of the pathology of melanoma is crucial for the surgeon to deliver optimal care to the patient with melanoma. Pathology provides diagnostic data, offers prognostic information, and, to a large extent, directs management. This article reviews several aspects of the pathology of melanoma, with special relevance to the surgeon, including benign clinicopathologic simulators of melanoma, fundamental concepts of the pathology of melanoma, histopathologic prognostic factors of melanoma, approach to lymph nodes, and implications of the revised staging system.

Diagnosis, Differential↗
PubMedDate not supplied

Research uses of neuropathological data.

The study of relationships between neuropathological characteristics and behavioral, structural, chemical, and molecular variables offers immense promise for understanding the basic pathophysiology of Alzheimer's disease. This position paper examines the need for standardized procedures and quantitation if neuropathological data are to be optimally useful among laboratories investigating the biology of Alzheimer's disease. These requirements include standardized fixation, embedding, sectioning, staining, brain regions and sampling methods. In addition, the definition of the structures to be quantified, such as plaque type(s), needs to be rigorously specified. Unbiased stereological methods for quantification should be used. These needs for optimal research utility exceed the needs and practicality for diagnostic purposes, suggesting a two-tiered approach to the neuropathology of Alzheimer's disease: diagnostic and research.

Aged↗
PubMed2002

Lung cancer evolution to preinvasive management.

Cancer screening measures generally are accepted for cervical, breast, and colon cancer. With prostate cancer screening, the practice is used broadly, but the evidence for this approach is not established clearly. The aggregate clinical experience with these screening procedures provides a useful precedent to consider in designing a new approach to lung cancer screening. For instance, formidable logistic issues exist in responsibly evaluating the vast at-risk population for lung cancer. Obvious issues include the needs for cost-economy and precise classification procedures. In the field of cervical cancer screening, recent developments in automated image analysis highlight the potential for improving the precision of diagnosis by moving beyond traditional manual cytomorphologic evaluation. The authors have outlined how the overexpression of hnRNP A2/B1 was associated significantly with the eventual development of lung cancer, as corroborated by several independent studies. In discussing this marker, they reviewed several issues with relevance to the general challenge in using biomarkers as screening tools for lung cancer. The experience with cervical cancer screening informs the development of a cellular diagnostic screening platform for lung cancer. Issues such as optimized cell preparation, reproducibility, and assay precision are fundamental to the success of the platform for lung cancer detection. The recent Institute of Medicine study of health care delivery provides an excellent point of departure in outlining the global infrastructure that will be necessary in the evolution of a prevention-oriented lung cancer care system. The power of early detection in saving lives from cancer is reflected in the fact that more people die from a single cancer without any validated screening tool (i.e., lung cancer) than die from the aggregate of the four other major cancers, including breast cancer, colon cancer, prostate cancer, and cervical cancer cases--which all have more established early detection approaches. New technologies may provide an opportunity to engage lung cancer routinely at a fundamentally early stage in its natural history, which may provide an opportunity for clinicians to reconsider what may be the best way to manage lung cancer. Further sustained efforts will be required to define the true value of these new approaches through clinical trials as the specialty moves responsibly to routine preventative care of individuals at risk for lung cancer.

Aerosols↗
PubMed1996

Spiral (helical) CT of the renal vasculature.

The renal arteries are among the most challenging of the major aortic branches to image with spiral CT. Optimization of CT acquisition parameters is critical to creating diagnostic renal CT angiograms. When careful attention is paid to prescribing these examinations, renal CT angiography can be a very useful, noninvasive alternative to conventional angiography for the assessment of renal artery stenosis, screening of potential renal donors, planning repair of ureteropelvic junction stenoses, and identification of relevant renal artery relationships to abdominal aortic lesions. This review outlines important technical considerations for performing renal CT angiography and examines currently published data on the utility of spiral CT in a variety of clinical conditions.

Angiography↗
PubMed1997

The effect of normalization in reducing variability in regional wall thickening.

This study was performed to evaluate a new method for measuring regional left ventricular wall thickening in terms of its variability, normal range, and diagnostic sensitivity. Two-dimensional echocardiographic images in the parasternal short-axis view of 44 normal patients and 17 patients with recent myocardial infarction were analyzed. Regional wall thickness was measured according to the centerline method at 100 chords. Wall thickening at each chord i was calculated as the change in wall thickness between end diastole and end systole at chord i, normalized by the average end-diastolic thickness of the wall segment extending from chord (i - n) to chord (i + n). Five widths of the normalization segment, defined as (2n + 1), were tested: 1 (baseline method), 5, 11, 15, and 21 chords. Widening the normalization segment significantly reduced point-to-point variability by up to 20% (p = 0.0001) evenly over the entire left ventricular contour. The magnitude of reduction approached a plateau at a normalization segment width of 11 chords. The normal mean and standard deviation for regional wall thickening were also reduced slightly but significantly in a progressive and uniform manner. The apparent severity of hypokinesis worsened by up to 0.1 +/- 0.1 SD (p = 0.006) as the normalization segment was widened. The circumferential extent of hypokinesis was not lengthened significantly until the normalization segment was 21 chords wide. The magnitude of hyperkinesis was unchanged. Normalizing over a wider segment of the myocardium reduces variability in the measurement of wall thickening, widens the separation between normal patients and those with disease, and enhances the diagnostic accuracy of quantitative two-dimensional echocardiography. The optimal normalization segment width is 11 chords.

Echocardiography↗
PubMed1998

Clinical diagnosis of heterozygous dystrophin gene deletions by fluorescence in situ hybridization.

Two-thirds of patients affected by Duchenne or Becker muscular dystrophy (DMD/BMD) carry large intra-genic deletions in the dystrophin gene. In males, the deletions can be efficiently detected using multiplex polymerase chain reaction (PCR) and Southern blotting. In contrast, deletion detection in carrier females is complicated by the presence of a normal gene copy on the second X-chromosome. We have analyzed the boundaries of 570 deletions and 34 duplications in the dystrophin gene identified in the São Paulo and Leiden diagnostic laboratories. The data were used to select an optimal set of cosmid probes for the detection of the most frequently deleted areas of the dystrophin gene. Six cosmids were evaluated in fluorescence in situ hybridization (FISH) experiments to assess deletions in 21 heterozygous deletion-carriers and nine controls. No discrepancy was found between the FISH analysis and the molecular data, demonstrating the accuracy of the technique for carrier detection in Duchenne and Becker muscular dystrophy.

DNA Probes↗