scholarly journals Comparing Non-invasive Diagnostic Methods for Arteriovenous Fistula Stenosis: A Prospective Study

2020 ◽  
Author(s):  
Sukit Raksasuk ◽  
Satit Rojwatcharapibarn ◽  
Thatsaphan Srithong
Keyword(s):  
Physical Examination ◽  
Doppler Ultrasonography ◽  
Diagnostic Methods ◽  
Dilution Method ◽  
Roc Curve Analysis ◽  
Severe Stenosis ◽  
Discriminative Ability ◽  
Flow Measurements ◽  
Ultrasound Dilution ◽  
Non Invasive

Abstract Background International guidelines recommended screening for AVF stenosis using various non-invasive methods. The previous studies have reported conflicting results. This study aims to evaluate the utility of the different non-invasive AVF flow measurements for detecting AVF stenosis. Methods We evaluated 23 HD patients with the clinical suspicion for AVF stenosis based on physical examination or high venous pressures during. Patients underwent all three non-invasive measurements including ultrasound dilution, urea dilution, and Doppler ultrasonography. Fistulography was performed to confirm the degree of AVF stenosis in all patients. Results Fistulography revealed AVF stenosis in eighteen patients, twelve of whom had severe stenosis (greater than 50% stenosis). About the location of the stenotic lesions, eight were at the inflow site, six at the outflow site, and four at both sites. In those AVFs with severe stenosis, median access flows were 625 mL/min by ultrasound dilution method, 615 mL/min by urea dilution method, and 590 mL/min by Doppler ultrasonography. Receiver operating characteristic (ROC) curve analysis showed that Doppler ultrasonography had a high discriminative ability and the averaged areas under the curves were 0.933 (95% confidence interval [CI], 0.81 to 0.99) for stenosis and 0.929 (95% CI, 0.82 to 0.99) for severe stenosis. The sensitivity of each method for prediction of access stenosis was 73%, 73%, 80% by using the ultrasound dilution, urea dilution, and Doppler ultrasonography methods, respectively. The specificity of each method was 40%, 80%, and 100% respectively. Physical examination showed 80% sensitivity and 80% specificity for detecting AVF stenosis. The combination of non-invasive access flow measurement with physical examination increased the sensitivity for detection of AVF stenosis to 80%, 93%, and 93% respectively. Conclusions Doppler ultrasound combine with physical examination, was more accurate than other non-invasive methods for detection of AVF stenosis.

scholarly journals Comparing Non-invasive Diagnostic Methods for Arteriovenous Fistula Stenosis: A Prospective Study

2020 ◽  
Author(s):  
Sukit Raksasuk ◽  
Satit Rojwatcharapibarn ◽  
Thatsaphan Srithong
Keyword(s):  
Physical Examination ◽  
Doppler Ultrasonography ◽  
Diagnostic Methods ◽  
Dilution Method ◽  
Roc Curve Analysis ◽  
Severe Stenosis ◽  
Discriminative Ability ◽  
Flow Measurements ◽  
Ultrasound Dilution ◽  
Non Invasive

Abstract Background International guidelines recommended screening for AVF stenosis using various non-invasive methods. The previous studies have reported conflicting results. This study aims to evaluate the utility of the different non-invasive AVF flow measurements for detecting AVF stenosis. Methods We evaluated 23 HD patients with the clinical suspicion for AVF stenosis based on physical examination or high venous pressures during. Patients underwent all three non-invasive measurements including ultrasound dilution, urea dilution, and Doppler ultrasonography. Fistulography was performed to confirm the degree of AVF stenosis in all patients. Results Fistulography revealed AVF stenosis in eighteen patients, twelve of whom had severe stenosis (greater than 50% stenosis). About the location of the stenotic lesions, eight were at the inflow site, six at the outflow site, and four at both sites. In those AVFs with severe stenosis, median access flows were 625 mL/min by ultrasound dilution method, 615 mL/min by urea dilution method, and 590 mL/min by Doppler ultrasonography. Receiver operating characteristic (ROC) curve analysis showed that Doppler ultrasonography had a high discriminative ability and the averaged areas under the curves were 0.933 (95% confidence interval [CI], 0.81 to 0.99) for stenosis and 0.929 (95% CI, 0.82 to 0.99) for severe stenosis. The sensitivity of each method for prediction of access stenosis was 73%, 73%, 80% by using the ultrasound dilution, urea dilution, and Doppler ultrasonography methods, respectively. The specificity of each method was 40%, 80%, and 100% respectively. Physical examination showed 80% sensitivity and 80% specificity for detecting AVF stenosis. The combination of non-invasive access flow measurement with physical examination increased the sensitivity for detection of AVF stenosis to 80%, 93%, and 93% respectively. Conclusions Doppler ultrasound combine with physical examination, was more accurate than other non-invasive methods for detection of AVF stenosis.

The Utility of Non-invasive Tests for Detection of Previous Proximal-vein Thrombosis

1995 ◽  
Vol 73 (04) ◽  
pp. 592-596 ◽  
Author(s):  
Sabina Villalta ◽  
Paolo Prandoni ◽  
Alberto Cogo ◽  
Paola Bagatella ◽  
Andrea Piccioli ◽  
...  
Keyword(s):  
Clinical Evaluation ◽  
Femoral Vein ◽  
Clinical Score ◽  
Diagnostic Methods ◽  
Popliteal Vein ◽  
Venous Reflux ◽  
Study Objective ◽  
Vein Thrombosis ◽  
Non Invasive ◽  
The Common

SummaryBackground. Despite the availability of several diagnostic methods for the detection of deep-vein thrombosis (DVT), the identification of previous episodes of DVT remains a diagnostic challenge.Study objective. To assess the reliability of a combination of a standardized clinical score with three non-invasive tests: compression ultrasonography (CUS), Doppler ultrasound (DUS), and photoplethysmography (PPG), in determining the presence or the absence of previous proximal DVT.Methods. One hundred consecutive unselected outpatients were identified, who had undergone contrast venography six to nine years previously because of the clinical suspicion of DVT (confirmed in 43). They were blindly reinvestigated by a panel of trained operators unaware of venography results. They underwent a clinical evaluation of the lower limb, by applying a standardized score to five symptoms and six signs (grading each item from 0 to 3); a PPG test to determine the venous refilling time; a DUS test to determine the venous reflux separately in the common femoral and the popliteal vein; and a CUS test to determine vein compressibility in the same regions.Results. An abnormal CUS test and/or the demonstration of venous reflux in the popliteal region and/or a high clinical score (≥ 8) identified twenty-four of the 43 (56%) DVT + patients with a specificity of 89%. The combination of normal CUS with the absence of venous reflux in both the common femoral and popliteal vein and a low clinical score excluded previous thrombosis in 45 (79%) of the 57 DVT- patients (negative predictive value, 78%). Abnormal venous reflux in the isolated common femoral vein did not reliably predict the presence or absence of previous DVT. However, this occurred in only 13 (13%) patients. The PPG determination of venous refilling time did not improve the results obtained with the other tests.Conclusions. The combination of a standardized clinical evaluation with the results of CUS and DUS can reliably diagnose or exclude previous proximal-vein thrombosis in almost 90% of patients with previous episodes of suspected DVT.

Diagnosis of helicobacter pylori infection: problems and prospects

2020 ◽  
pp. 54-59
Author(s):  
A. S. Molostova ◽  
N. S. Gladyshev ◽  
A. V. Svarval ◽  
R. S. Ferman ◽  
A. B. Karasyova ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Urease Activity ◽  
Diagnostic Methods ◽  
Study Group ◽  
Biochemical Method ◽  
Antimicrobial Drugs ◽  
Non Invasive ◽  
Number Of Patients ◽  
Pcr Method ◽  
Positive Results

(HP) infection was performed using invasive and non-invasive methods. The study group consisted of 95 patients with dyspepsia. HP infection was detected in 47 patients (49.4 %). The expediency of using a set of diagnostic methods for detecting HP (PCR, immunochromatographic, bacteriological and method for determining urease activity) is proved. Most often (100 %) in patients HP infection was detected in biopsies using the PCR method. Somewhat less frequently it was detected when examining biopsies with an invasive biochemical method (AMA RUT Reader) (82 %) and fecal immunochromatographic method (83 %). Despite the fact that helicobacteriosis was detected bacteriologically in a small number of patients (24 %), this method is of particular value, since it allows you to assess the sensitivity to antimicrobial drugs and probiotics, and does not give false positive results.

Non-Invasive Distinction of Non-Alcoholic Fatty Liver Disease using Urinary Volatile Organic Compound Analysis: Early Results

2015 ◽  
Vol 24 (2) ◽  
pp. 197-201 ◽  
Author(s):  
Ramesh P. Arasaradnam ◽  
Michael McFarlane ◽  
Emma Daulton ◽  
Erik Westenbrink ◽  
Nicola O’Connell ◽  
...  
Keyword(s):  
Liver Disease ◽  
Pilot Study ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
Diagnostic Methods ◽  
Screening Methods ◽  
Alcoholic Fatty Liver ◽  
Non Invasive ◽  
Volatile Organic ◽  
Alcoholic Fatty Liver Disease

Background & Aims: Non-Alcoholic Fatty Liver Disease (NAFLD) is the commonest cause of chronic liver disease in the western world. Current diagnostic methods including Fibroscan have limitations, thus there is a need for more robust non-invasive screening methods. The gut microbiome is altered in several gastrointestinal and hepatic disorders resulting in altered, unique gut fermentation patterns, detectable by analysis of volatile organic compounds (VOCs) in urine, breath and faeces. We performed a proof of principle pilot study to determine if progressive fatty liver disease produced an altered urinary VOC pattern; specifically NAFLD and Non-Alcoholic Steatohepatitis (NASH).Methods: 34 patients were recruited: 8 NASH cirrhotics (NASH-C); 7 non-cirrhotic NASH; 4 NAFLD and 15 controls. Urine was collected and stored frozen. For assay, the samples were defrosted and aliquoted into vials, which were heated to 40±0.1°C and the headspace analyzed by FAIMS (Field Asymmetric Ion Mobility Spectroscopy). A previously used data processing pipeline employing a Random Forrest classification algorithm and using a 10 fold cross validation method was applied.Results: Urinary VOC results demonstrated sensitivity of 0.58 (0.33 - 0.88), but specificity of 0.93 (0.68 - 1.00) and an Area Under Curve (AUC) 0.73 (0.55 -0.90) to distinguish between liver disease and controls. However, NASH/NASH-C was separated from the NAFLD/controls with a sensitivity of 0.73 (0.45 - 0.92), specificity of 0.79 (0.54 - 0.94) and AUC of 0.79 (0.64 - 0.95), respectively.Conclusions: This pilot study suggests that urinary VOCs detection may offer the potential for early non-invasive characterisation of liver disease using 'smell prints' to distinguish between NASH and NAFLD.

CURRENT APPROACH ON CUTANEOUS MELANOMA DIAGNOSTICS

2019 ◽  
Vol 65 (5) ◽  
pp. 638-644
Author(s):  
Mariya Ebert ◽  
Georgiy Gafton ◽  
Grigoriy Zinovev ◽  
I. Gafton
Keyword(s):  
Physical Examination ◽  
Cutaneous Melanoma ◽  
Growth Dynamics ◽  
Current Approach ◽  
Clinical Diagnostics ◽  
Skin Tumors ◽  
Steady Increase ◽  
Non Invasive ◽  
Early Stages ◽  
Other Information

Melanoma is on the first place in mortality among all skin tumors. Over the past 50 years, there has been a steady increase in the incidence of cutaneous melanoma compared to other types of tumors. Rates of 5-year survival are fairly high, if melanoma is diagnosed in the early stages, which requires adequate diagnostics and treatment. Melanoma diagnostic, especially in the early stages, can be problematic even for an experienced dermatologist. However, primary contact doctor can be any specialty. Melanoma and other skin tumors can be detected by physical examination during treatment for another disease. Phenotypic risks factors, anamnestic data, and physical examination data are important in cutaneous melanoma diagnostics. The sensitivity of clinical diagnosis during a visual examination by an experienced dermatologist is approximately 70 percent. However, dermascopy can significantly increase the accuracy of a clinical diagnostics. In recent years there has been an active research for new non-invasive methods and algorithms for cutaneous melanoma diagnostics. The main goal of non-invasive diagnostics is to determine need for biopsy. This decision should be based on a combination of clinical and dermascopic examinations and other information, including growth dynamics, symptoms and medical history. Thus, an adequate diagnostic of cutaneous melanoma, including non-invasive and invasive methods, is a simple and economically viable way to early detection of cutaneous melanoma and to reduce mortality from this aggressive disease.

Diagnostic Value of Non-Invasive Prenatal Screening of β-thalassemia by Cell Free Fetal DNA and Fetal NRBC

2019 ◽  
Vol 19 (2) ◽  
pp. 105-111
Author(s):  
Nadia Shafei ◽  
Mohammad Saeed Hakhamaneshi ◽  
Massoud Houshmand ◽  
Siavash Gerayeshnejad ◽  
Fardin Fathi ◽  
...  
Keyword(s):  
Sensitivity And Specificity ◽  
Multiple Displacement Amplification ◽  
Diagnostic Value ◽  
Diagnostic Methods ◽  
Beta Thalassemia ◽  
Non Invasive ◽  
Fetal Dna ◽  
Prenatal Diagnostic ◽  
Cell Free Fetal Dna ◽  
Invasive Techniques

Background: Beta thalassemia is a common disorder with autosomal recessive inheritance. The most prenatal diagnostic methods are the invasive techniques that have the risk of miscarriage. Now the non-invasive methods will be gradually alternative for these invasive techniques. Objective: The aim of this study is to evaluate and compare the diagnostic value of two non-invasive diagnostic methods for fetal thalassemia using cell free fetal DNA (cff-DNA) and nucleated RBC (NRBC) in one sampling community. Methods: 10 ml of blood was taken in two k3EDTA tube from 32 pregnant women (mean of gestational age = 11 weeks), who themselves and their husbands had minor thalassemia. One tube was used to enrich NRBC and other was used for cff-DNA extraction. NRBCs were isolated by MACS method and immunohistochemistry; the genome of stained cells was amplified by multiple displacement amplification (MDA) procedure. These products were used as template in b-globin segments PCR. cff-DNA was extracted by THP method and 300 bp areas were recovered from the agarose gel as fetus DNA. These DNA were used as template in touch down PCR to amplify b-globin gen. The amplified b-globin segments were sequenced and the results compared with CVS resul. Results: The data showed that sensitivity and specificity of thalassemia diagnosis by NRBC were 100% and 92% respectively and sensitivity and specificity of thalassemia diagnosis by cff-DNA were 100% and 84% respectively. Conclusion: These methods with high sensitivity can be used as screening test but due to their lower specificity than CVS, they cannot be used as diagnostic test.

Comparison of LBM and FVM in the estimation of LAD stenosis

2021 ◽  
pp. 095441192110169
Author(s):  
Jian Liu ◽  
Yong Yu ◽  
Chenqi Zhu ◽  
Yu Zhang
Keyword(s):  
Stokes Equations ◽  
Flow Simulation ◽  
Diagnostic Methods ◽  
Computational Time ◽  
Speed Ratio ◽  
Maximum Speed ◽  
Fractional Flow ◽  
Local Flow ◽  
Non Invasive ◽  
Flow Reserve

The finite volume method (FVM)-based computational fluid dynamics (CFD) technology has been applied in the non-invasive diagnosis of coronary artery stenosis. Nonetheless, FVM is a time-consuming process. In addition to FVM, the lattice Boltzmann method (LBM) is used in fluid flow simulation. Unlike FVM solving the Navier–Stokes equations, LBM directly solves the simplified Boltzmann equation, thus saving computational time. In this study, 12 patients with left anterior descending (LAD) stenosis, diagnosed by CTA, are analysed using FVM and LBM. The velocities, pressures, and wall shear stress (WSS) predicted using FVM and LBM for each patient is compared. In particular, the ratio of the average and maximum speed at the stenotic part characterising the degree of stenosis is compared. Finally, the golden standard of LAD stenosis, invasive fractional flow reserve (FFR), is applied to justify the simulation results. Our results show that LBM and FVM are consistent in blood flow simulation. In the region with a high degree of stenosis, the local flow patterns in those two solvers are slightly different, resulting in minor differences in local WSS estimation and blood speed ratio estimation. Notably, these differences do not result in an inconsistent estimation. Comparison with invasive FFR shows that, in most cases, the non-invasive diagnosis is consistent with FFR measurements. However, in some cases, the non-invasive diagnosis either underestimates or overestimates the degree of stenosis. This deviation is caused by the difference between physiological and simulation conditions that remains the biggest challenge faced by all CFD-based non-invasive diagnostic methods.

scholarly journals Metal Oxide Nanorods-Based Sensor Array for Selective Detection of Biomarker Gases

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1922
Author(s):  
Gwang Su Kim ◽  
Yumin Park ◽  
Joonchul Shin ◽  
Young Geun Song ◽  
Chong-Yun Kang
Keyword(s):  
Real Time ◽  
Sensor Array ◽  
High Sensitivity ◽  
Gas Analysis ◽  
Diagnostic Methods ◽  
Real Time Monitoring ◽  
Non Invasive ◽  
Sensitivity And Selectivity ◽  
Breath Gas Analysis ◽  
Angle Method

The breath gas analysis through gas phase chemical analysis draws attention in terms of non-invasive and real time monitoring. The array-type sensors are one of the diagnostic methods with high sensitivity and selectivity towards the target gases. Herein, we presented a 2 × 4 sensor array with a micro-heater and ceramic chip. The device is designed in a small size for portability, including the internal eight-channel sensor array. In2O3 NRs and WO3 NRs manufactured through the E-beam evaporator’s glancing angle method were used as sensing materials. Pt, Pd, and Au metal catalysts were decorated for each channel to enhance functionality. The sensor array was measured for the exhaled gas biomarkers CH3COCH3, NO2, and H2S to confirm the respiratory diagnostic performance. Through this operation, the theoretical detection limit was calculated as 1.48 ppb for CH3COCH3, 1.9 ppt for NO2, and 2.47 ppb for H2S. This excellent detection performance indicates that our sensor array detected the CH3COCH3, NO2, and H2S as biomarkers, applying to the breath gas analysis. Our results showed the high potential of the gas sensor array as a non-invasive diagnostic tool that enables real-time monitoring.

scholarly journals Biological autoluminescence for assessing oxidative processes in yeast cell cultures

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Petra Vahalová ◽  
Kateřina Červinková ◽  
Michal Cifra
Keyword(s):  
Reactive Oxygen Species ◽  
Light Emission ◽  
Reactive Oxygen ◽  
Modern Medicine ◽  
Diagnostic Methods ◽  
Pathological State ◽  
Oxygen Species ◽  
Non Invasive ◽  
Oxidative Processes ◽  
Physical And Chemical

AbstractNowadays, modern medicine is looking for new, more gentle, and more efficient diagnostic methods. A pathological state of an organism is often closely connected with increased amount of reactive oxygen species. They can react with biomolecules and subsequent reactions can lead to very low endogenous light emission (biological autoluminescence—BAL). This phenomenon can be potentially used as a non-invasive and low-operational-cost tool for monitoring oxidative stress during diseases. To contribute to the understanding of the parameters affecting BAL, we analyzed the BAL from yeast Saccharomyces cerevisiae as a representative eukaryotic organism. The relationship between the BAL intensity and the amount of reactive oxygen species that originates as a result of the Fenton reaction as well as correlation between spontaneous BAL and selected physical and chemical parameters (pH, oxygen partial pressure, and cell concentration) during cell growth were established. Our results contribute to real-time non-invasive methodologies for monitoring oxidative processes in biomedicine and biotechnology.

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