Search results for "specificity"
showing 10 items of 2234 documents
Analysis of radiolucent gallstones by computed tomography for in vivo estimation of stone components.
1990
. Successful oral litholytic and other non-operative therapies of gallstones require exact determination of the stone components. Since computed tomography (CT) provides highly sensitive measurement of density, we performed a study to evaluate whether CT measurement of stone density allows a prediction of the composition of radiolucent gallstones. Twenty-eight patients presenting with 29 radiolucent gallbladder (n= 17) or common bile duct stones (n=12) were included. Prior to operative or endo-scopic therapy the attenuation values (Hounsfield Units, HU) were assessed in vivo by CT under standardized conditions (Somatom II, 125 KV, 130 mAs). After surgical or endoscopic stone removal the con…
Plain film, CT and MRI sensibility in the evaluation of intraorbital foreign bodies in an in vitro model of the orbit and in pig eyes.
2000
Detection and characterization of intraorbital foreign bodies (IFB) is fundamental in acute trauma setting, preventing inflammatory sequelae or complications related to IFB movements when a MRI study is planned. Papers concerning plain film and CT sensibility in IFB detection show controversial results. For this reason we investigated plain film, CT and MRI sensibility in the evaluation of IFB. For an in vitro model, specimens of dry and fresh wood, glass, iron, plastic and graphite were immersed in animal lard and in a 0.9 % sodium chloride plus 3.5 g/dl human serum albumin solution. Specimens of different size and nature where also implanted into enucleated pig eyes. Air bubbles were intr…
Imaging of Ventriculoperitoneal Shunt Complications: Comparison of Whole Body Low-Dose Computed Tomography and Radiographic Shunt Series.
2016
OBJECTIVE To determine diagnostic value and radiation exposure of low-dose computed tomography (LD-CT) compared to radiographic shunt series (SS) for the detection of ventriculoperitoneal (VP) shunt complications. METHODS Fourteen VP shunts were implanted in 7 swine cadavers. Mechanical complications were induced in 50% of VP shunts. Low-dose CT (80 kVp, 10 mAs, Pitch = 1.5) and SS were acquired. Dose area product (DAP) and effective doses for SS and LD-CT were collected. Scoring of diagnostic confidence and blinded readings of SS and CT data were performed. RESULTS The sensitivity of LD-CT was high (0.97; 95% confidence interval, 0.91-1.00) with excellent interobserver agreement (κ = 0.88)…
Accuracy of automatic airway morphometry in computed tomography-correlation of radiological-pathological findings.
2010
Abstract Objectives Airway morphology shows characteristic changes in different pathologies. This study assesses the accuracy of a current automatic airway assessment technique by correlating CT images of porcine airways to histological slices of the same localization. Materials and methods Four isolated and ventilated porcine lungs were frozen in a liquid nitrogen bath and examined with a CT scanner (MDCT). This technique both preserved normal radiomorphological appearance and made it possible to slice the specimens for histological examination for subsequent correlation. The parameters wall thickness (WT), wall percentage (WP), and total diameter (TD) were assessed by computer-aided measu…
Prosurvival effect of human wild-type alpha-synuclein on MPTP-induced toxicity to central but not peripheral catecholaminergic neurons isolated from …
2010
In the present work we report the generation of a new line of alpha-synuclein (alpha-SYN) transgenic mice in which the human wild-type alpha-SYN cDNA is expressed under the control of a tyrosine hydroxylase (TH) promoter. We provide evidence that the ectopic protein is found in TH expressing neurons of both central and peripheral nervous systems. The transgene is expressed very early in development coinciding with the activity of the TH promoter and in the adult brain the human protein distributes normally to the nerve endings and cell bodies of dopaminergic nigral neurons without any evidence of abnormal aggregation. Our results indicate that expression of human wild-type alpha-SYN does no…
Value of routine abdominal and lymph node sonography in the follow-up of breast cancer patients.
1994
Abstract Objective: The aim of this study was to review usefulness and intervals for abdominal sonography during the follow-up of breast cancer patients. Additionally, we assessed the value of regional lymph node sonography in patients with possible locoregional recurrence. Subjects: Retrospectively, 2657 abdominal ultrasound examinations of 414 patients and 299 sonographic examinations of the regional lymph nodes in 227 patients after surgical treatment for breast cancer were evaluated. Results: Follow-up abdominal sonography revealed metastases in 6.8% of patients, and in 1% of examinations. There was no dependence on the initial T- or N-stage. At sonography of the regional lymph nodes in…
Prospective comparison of CT angiography of the legs with intraarterial digital subtraction angiography.
1996
The aim of this study was to determine the accuracy of CT angiography (CTA) with a single spiral acquisition for the diagnosis of arterial stenoses and occlusion in patients with peripheral vascular occlusive disease.In a prospective study, intraarterial digital subtraction angiography and i.v. CTA from the groin to the lower calves were performed on 50 patients with vascular occlusive disease. Maximum-intensity-projection images in multiple views were produced. The accuracy of CTA with and without analysis of the axial scans was determined with digital subtraction angiography as the standard.The sensitivities of CTA were 100% for the diagnosis of femoral artery occlusion, 100% for the dete…
D-dimer testing: advantages and limitations in emergency medicine for managing acute venous thromboembolism
2007
Patients with suspected deep vein thrombosis (DVT) or pulmonary embolism (PE) are frequently admitted to an Emergency Department (ED) for initial evaluation. However, management of patients with suspicion of acute venous thromboembolism (VTE) in this clinical setting can be difficult; in fact symptoms and signs of DVT are non-specific and can be found in a broad spectrum of non-thrombotic disorders. An accurate and timely objective diagnosis is necessary for immediate and correct identification of patients with acute VTE, while avoiding the bleeding risk associated with unnecessary anticoagulant therapy in patients where DVT or PE have been ruled out. The diagnostic approach to patients wit…
The effect of Dextransulfate 500 on the pathogenesis of herpes simplex virus infections in weanling mice
1978
Intraperitoneal (i.p.) injection of Dextran Sulfate (D.S.) 500 during a limited period of time influences the course of herpes simplex-virus-infections. D.S.500 was found to reduce the resistance of mice for some herpes simplex-virus strains (Len, L3-2s, Haase) if given between 16 hours before and 2 hours after i.p. infection. The decrease of resistance could be correlated with an increase of the virus content of liver, spleen, brain and spinal cord. Injection of herpes simplex-virus-specific immune serum counteracted the effect of D.S.500 on the course of infections. Conversely, D.S.500 increased the resistance of mice to another group of herpes simplex-viruses (strains D-316, Thea, DD), i…
Localization of the bradykinin B2 receptor in uterus, bladder and Madin-Darby canine kidney cells
1997
Kinins are biologically active peptides that act through specific receptors, B1 and B2. Here we describe the localization of the bradykinin B2 receptor in Madin-Darby canine kidney cells and in the uterus and urinary bladder of rat or human origin. We discuss the suitability of anti-peptide antibodies to assess the tissue distribution of bradykinin B2 receptors.