Search results for " DOP"
showing 10 items of 770 documents
Modelling of the Ischemic Penumbra
1999
What happens to the ischemic penumbra – defined as a territory of critically reduced blood flow in the close neighborhood of an ischemic core – determines outcome after stroke. Currently the pathophysiology of the penumbra is studied predominantly in rat models with occlusion of the middle cerebral artery. Here we propose two other rat models with distinct advantages. One produces a large territory of critical flow reduction in the cortex of one hemisphere without presence of an infarct core: this model is suited to study mediator mechanisms that may transform the penumbra into necrotic tissue. It is produced by occluding one carotid artery and in addition reducing arterial pressure to 50mm…
1043 Evaluation of Pediatric Testes After Surgery by Laser Doppler and White Light Spectroscopy
2012
Aim To evaluate testes after unilateral orchiopexy Laser Doppler and white light spectroscopy and compare microcirculation with contralaterat testis and healthy controls. Methods A combination of the laser Doppler (determination of blood flow) and white light spectroscopy (determination of oxygen saturation and hemoglobin amount) is used to determine microcirculation at two different depth levels non-invasively. Patients were recruited after unilateral orchiopexy. Controls were age-matched boys without relevant disease. Ethical approval was obtained. Results 99 patients were included after unilateral orchiopexy at the age of 3.5 years (+-2.9 years). 65% underwent surgery after their second …
Implementation of computed tomography angiography (CTA) and computed tomography perfusion (CTP) in Polish guidelines for determination of cerebral ci…
2021
Background: Brain death/death by neurologic criteria (BD/DNC) guidelines are routinely analyzed, compared and updated in the majority of countries and are later implemented as national criteria. At the same time, extensive works have been conducted in order to unify clinical procedures and to validate and implement new technologies into a panel of ancillary tests. Recently evaluated computed tomography angiography and computed tomography perfusion (CTA/CTP) seem to be superior to traditionally used digital subtraction angiography (DSA), transcranial Doppler (TCD) and cerebral perfusion scintigraphy for diagnosis of cerebral circulatory arrest (CCA). In this narrative review, we would like t…
Transkranielle Dopplersonographie bei Kopf-Hals-Tumoren*
1991
Transcranial Doppler ultrasound (TCD) recording is a non-invasive diagnostic procedure for the evaluation of the cerebral collateral flow in patients, in whom therapeutic ligation or resection of the common and/or internal carotid artery is planned. Patients are first examined under resting conditions, and then under manual compression of the ipsilateral carotid artery. Since January 1989, 31 ENT and neurosurgical patients have been examined. In all patients an immediate decrease in flow velocity in the middle cerebral artery (mca) of about 25% to 90% was recorded. In 42.8% of the patients the mca flow velocity reached 90% or more of its value under normal conditions within a short period. …
CA125 but not NT-proBNP predicts the presence of a congestive intrarenal venous flow in patients with acute heart failure
2021
Abstract Background Intrarenal venous flow (IRVF) measured by Doppler ultrasound has gained interest as a potential surrogate marker of renal congestion and adverse outcomes in heart failure. In this work, we aimed to determine if antigen carbohydrate 125 (CA125) and plasma amino-terminal pro-B-type natriuretic peptide (NT-proBNP) are associated with congestive IRVF patterns (i.e., biphasic and monophasic) in acute heart failure (AHF). Methods and results We prospectively enrolled a consecutive cohort of 70 patients hospitalized for AHF. Renal Doppler ultrasound was assessed within the first 24-h of hospital admission. The mean age of the sample was 73.5 ± 12.3 years; 47.1% were female, and…
Diagnosis of Endometrial Carcinoma: Predictive Value of Transvaginal Color Doppler
1995
The objective of this study was to determine whether transvaginal ultrasound plus color Doppler flow improve the ability to diagnose endometrial carcinoma and allow better discrimination between benign and malignant endometrial lesions. One hundred thirty women with abnormal uterine bleeding were evaluated with transvaginal color Doppler before fractional dilatation and curettage (D&C). The endometrial line thickness and endometrial characteristics were evaluated by endosonography. The resistive and pulsatile indices of the uterine arteries and of the endometrium were evaluated with transvaginal color Doppler. Following D&C and tissue diagnosis, women were divided into two groups, 62 with a…
Dilation of the ductus venosus by stent implantation increases placental blood perfusion in fetal sheep.
2006
The reduction of resistance to flow in the ductus venous (DV) and a decrease of blood supply to the liver serve for the survival of the fetus during hypoxia. The present study investigated the influence of the increased diameter of the DV on placental blood perfusion.In 15 ewes with twin pregnancies at gestational ages of 117 +/- 4 days, a stent (4 or 5 mm) was placed into the DV of 1 twin (DV(stent) group) under ultrasound guidance. Blood flow rates in the umbilical vein (UV) and DV of both fetuses were measured using Doppler ultrasound. Eight pairs of twin fetuses were included for the final analysis.The dilatation of the DV increased the blood flow volume rate passed through the DV from …
Transesophageal contrast echocardiography is not always the gold standard method in the identification of a patent foramen ovale: A clinical case
2015
In the embryo, Eustachian valve is a crescent-shaped membrane extending from the lower margin of the inferior vena cava and the ostium of the coronary sinus into the right atrium toward fossa ovalis and tricuspid valve. At birth, after the functional closure of the foramen ovale, the Eustachian valve loses its function, reducing to an embryo remnant. According to growing evidence, a persistent Eustachian valve is a frequent finding in patients with a patent foramen ovale (PFO). By directing the blood from the inferior cava to the interatrial septum, it may prevent the spontaneous closure of PFO after birth and indirectly predispose to paradoxical embolism. Transesophageal contrast enhanced …
The progression rate of aortic stenosis: key to tailoring the management and potential target for treatment
2021
: Aortic stenosis is the most frequent valvular disease to require intervention in the western world and has always been featured as a progressive disease. The rate of progression can be assessed by carefully performed Doppler echocardiography and can vary greatly between individuals with a profound impact on prognosis. Unfortunately, the determinants of disease progression had been insufficiently studied and remain challenging to define, particularly in the outpatient setting. Multiple factors have been proposed and tested, but at present, there are no proven therapies to slow the course of the stenotic process. Heart valve clinics may be particularly important to define the progression ra…