Shunt flow of arteriovenous fistulas from plantar artery

Objective The purpose of this study was to visualize the shunt flow of arteriovenous fistulas (AVFs) passing towards the top side of the foot from the plantar artery. Methods Colour-flow duplex Doppler ultrasonography was performed in 112 patients who consulted an outpatient clinic with varicose veins and/or symptoms such as foot oedema, dullness, cramp and coldness. Thirteen age-and sex-matched healthy subjects served as controls. Results AVFs were detected in 86 of 112 patients (77%). They were also detected in 10 (77%) of 13 healthy subjects. The shunt flow pattern consisted of two phases of flow corresponding to systole and diastole, and the diastolic fraction of time–velocity integral was larger, although the peak flow velocity in systole was higher than that in diastole. Conclusion Colour-flow duplex Doppler ultrasonography is useful for non-invasive visualization of the shunt flow of AVFs connecting the plantar artery with the venous arch of the top side of the foot.

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Duplex doppler ultrasonography in the diagnosis of deep venous thrombosis of the lower extremities

Medicinski pregled ◽

10.2298/mpns0602011v ◽

2006 ◽

Vol 59 (1-2) ◽

pp. 11-14 ◽

Cited By ~ 2

Author(s):

Viktorija Vucaj-Cirilovic ◽

Kosta Petrovic ◽

Olivera Nikolic ◽

Viktor Till ◽

Dijana Niciforovic ◽

...

Keyword(s):

Venous Thrombosis ◽

Deep Venous Thrombosis ◽

Doppler Ultrasonography ◽

Varicose Veins ◽

Color Doppler ◽

Lower Extremities ◽

Postthrombotic Syndrome ◽

Duplex Doppler ◽

Age Range

Introduction. The aim of this study was to investigate the role of duplex Doppler ultrasonography in diagnosis of deep venous thrombosis (DVT) of the lower extremities. Material and methods. During a 2-year period, 860 patients were examined by duplex Doppler sonography. Among these, 619(72%) were women and 241 (28%) men, with the age-range of 16-91; (mean 56,2) years. Siemens Versa Pro color doppler was used, with 7MHz transducers. Findings were categorized into four categories: 1. deep venous thrombosis (DVT); 2. pathology predominantly related to superficial veins without DVT; 3. pathology of superficial and deep veins; 4. normal findings. Results. 185 (21%) patients had DVT, 366 (42.5%) patients had pre?dominant pathology of superficial veins: postthrombotic syndrome, superficial thrombophlebitis and varicose veins. 128 (14.9%) patients had pathology of superficial and deep veins. Normal findings were found in 181 (21.1%) patients. Conclusions. Various vascular and nonvascular diseases may mimic deep venous thrombosis, and that is why US should be used whenever possible to avoid unnecessary anticoagulant therapy. .

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Gastroepiploic artery coronary bypass graft: non-invasive patency evaluation using color and duplex Doppler ultrasonography

European Journal of Cardio-Thoracic Surgery ◽

10.1016/s1010-7940(96)01076-7 ◽

1997 ◽

Vol 11 (1) ◽

pp. 134-139 ◽

Cited By ~ 3

Author(s):

Stefaan Gryspeerdt ◽

Lieven Van Hoe ◽

Luc Mertens ◽

Guy Marchal ◽

Luc Stockx ◽

...

Keyword(s):

Doppler Ultrasonography ◽

Bypass Graft ◽

Coronary Bypass ◽

Gastroepiploic Artery ◽

Non Invasive ◽

Coronary Bypass Graft ◽

Duplex Doppler

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Value of duplex doppler ultrasonography in non-invasive assessment of children with chronic liver disease

World Journal of Gastroenterology ◽

10.3748/wjg.v16.i48.6139 ◽

2010 ◽

Vol 16 (48) ◽

pp. 6139 ◽

Cited By ~ 7

Author(s):

Mortada HF El-Shabrawi

Keyword(s):

Liver Disease ◽

Chronic Liver Disease ◽

Doppler Ultrasonography ◽

Chronic Liver ◽

Non Invasive ◽

Duplex Doppler

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Value of duplex Doppler ultrasonography for the evaluation of dysfunctional hemodialysis access arteriovenous fistulas prior to endovascular interventions

Journal of Clinical Ultrasound ◽

10.1002/jcu.22601 ◽

2018 ◽

Vol 46 (8) ◽

pp. 503-511 ◽

Cited By ~ 1

Author(s):

Isik Conkbayir ◽

Pinar Celtikci ◽

Onur Ergun ◽

Hasan Ali Durmaz

Keyword(s):

Doppler Ultrasonography ◽

Hemodialysis Access ◽

Arteriovenous Fistulas ◽

Endovascular Interventions ◽

Duplex Doppler

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Is non-invasive diagnosis of esophageal varices in patients with compensated hepatic cirrhosis possible by duplex Doppler ultrasonography?

Indian Journal of Gastroenterology ◽

10.1007/s12664-016-0630-7 ◽

2016 ◽

Vol 35 (1) ◽

pp. 60-66 ◽

Cited By ~ 6

Author(s):

Ritwik Chakrabarti ◽

Debraj Sen ◽

Vikram Khanna

Keyword(s):

Esophageal Varices ◽

Doppler Ultrasonography ◽

Hepatic Cirrhosis ◽

Non Invasive ◽

Duplex Doppler

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The role of Doppler ultrasonography in vascular access surveillance—controversies continue

The Journal of Vascular Access ◽

10.1177/1129729820928174 ◽

2021 ◽

pp. 112972982092817

Author(s):

Jan Malik ◽

Carlo Lomonte ◽

Mario Meola ◽

Cora de Bont ◽

Robert Shahverdyan ◽

...

Keyword(s):

Doppler Ultrasonography ◽

Blood Stream ◽

Chronic Hemodialysis ◽

Arteriovenous Fistulas ◽

Duplex Doppler ◽

Current Guidelines ◽

Time Diagnosis ◽

Lower Morbidity ◽

Ultrasound Surveillance

Chronic hemodialysis therapy required regular entry into the patient’s blood stream with adequate flow. The use of arteriovenous fistulas and grafts is linked with lower morbidity and mortality than the use of catheters. However, these types of accesses are frequently affected by stenoses, which decrease the flow and lead to both inadequate dialysis and access thrombosis. The idea of duplex Doppler ultrasound surveillance is based on the presumption that in-time diagnosis of an asymptomatic significant stenosis and its treatment prolongs access patency. Details of performed trials are conflicting, and current guidelines do not support ultrasound surveillance. This review article summarizes the trials performed and focuses on the reasons of conflicting results. We stress the need of precise standardized criteria of significant access stenosis and the weakness of the metaanalyses performed.

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Cerebellar rTMS and PAS effectively induce cerebellar plasticity

Scientific Reports ◽

10.1038/s41598-021-82496-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Martje G. Pauly ◽

Annika Steinmeier ◽

Christina Bolte ◽

Feline Hamami ◽

Elinor Tzvi ◽

...

Keyword(s):

Motor Cortex ◽

Healthy Subjects ◽

Primary Motor Cortex ◽

Cortical Excitability ◽

Motor Evoked Potentials ◽

Repetitive Transcranial Magnetic Stimulation ◽

Premotor Cortex ◽

Motor Pathways ◽

Non Invasive ◽

Cerebellar Plasticity

AbstractNon-invasive brain stimulation techniques including repetitive transcranial magnetic stimulation (rTMS), continuous theta-burst stimulation (cTBS), paired associative stimulation (PAS), and transcranial direct current stimulation (tDCS) have been applied over the cerebellum to induce plasticity and gain insights into the interaction of the cerebellum with neo-cortical structures including the motor cortex. We compared the effects of 1 Hz rTMS, cTBS, PAS and tDCS given over the cerebellum on motor cortical excitability and interactions between the cerebellum and dorsal premotor cortex / primary motor cortex in two within subject designs in healthy controls. In experiment 1, rTMS, cTBS, PAS, and tDCS were applied over the cerebellum in 20 healthy subjects. In experiment 2, rTMS and PAS were compared to sham conditions in another group of 20 healthy subjects. In experiment 1, PAS reduced cortical excitability determined by motor evoked potentials (MEP) amplitudes, whereas rTMS increased motor thresholds and facilitated dorsal premotor-motor and cerebellum-motor cortex interactions. TDCS and cTBS had no significant effects. In experiment 2, MEP amplitudes increased after rTMS and motor thresholds following PAS. Analysis of all participants who received rTMS and PAS showed that MEP amplitudes were reduced after PAS and increased following rTMS. rTMS also caused facilitation of dorsal premotor-motor cortex and cerebellum-motor cortex interactions. In summary, cerebellar 1 Hz rTMS and PAS can effectively induce plasticity in cerebello-(premotor)-motor pathways provided larger samples are studied.

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OPTICAL SENSOR SYSTEM FOR THE NON-INVASIVE ASSESSMENT OF ARTERIAL STIFFNESS QUANTIFIED BY FOURTH DERIVATIVE OF PHOTOPLETHYSMOGRAM

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237215500210 ◽

2015 ◽

Vol 27 (03) ◽

pp. 1550021

Author(s):

S. Mohanalakshmi ◽

A. Sivasubramanian

Keyword(s):

Arterial Stiffness ◽

Elastic Properties ◽

Healthy Subjects ◽

Vascular System ◽

Augmentation Index ◽

Cardiac Risk ◽

Contour Analysis ◽

Non Invasive ◽

Asymmetrical Shape ◽

Fourth Derivative

Arterial stiffness, resulting in loss of the elastic properties of arteries walls, is an indicator of cardiovascular risk, though the presence of disease is not clinically evident. Augmentation index is an important biomarker of arterial stiffness by which the cardiac risk of the patient can be diagnosed. The current paper outlines the non-invasive assessment of arterial stiffness by analyzing the morphology or contour of PhotoPlethysmoGraph (PPG) signal. PPG pulse was optically acquired with the developed photometric measurement device and the desired features were extracted to determine PPG augmentation Index (PAI) through advanced signal processing implemented in MATLAB. PAI was quantified by the fourth derivative of the signal by enhancing the location of inflection point (augmentation point) after conditioning the signal by efficient pre-processing and filtering techniques. The results reveal that the statistical distribution of PAI for healthy subjects presents a very low value and a very tight distribution. On the contrary, patients have a higher value of PAI and a wide asymmetrical shape of distribution. This work also establishes the usefulness of PPG contour analysis in the investigation of changes in the elastic properties of the vascular system. In conclusion, PAI has revealed to be a non-invasive indicator for arterial stiffness assessments.

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