Search results for " DOP"
showing 10 items of 770 documents
External polytetrafluoroethylene reinforcement of varicose autologous vein grafts in peripheral bypass surgery produces durable bypass function
2017
Abstract Objective Use of autologous veins as peripheral bypass graft may become critical in the presence of significant varicose degeneration of the harvested vein. External support of such dilated veins with standard polytetrafluoroethylene (PTFE) prostheses was recommended as an option to use these veins for peripheral bypass. A single-center experience with this technique regarding long-term graft function, secondary reinterventions, and potential graft degeneration is presented. Methods Between January 1995 and January 2006, there were 54 patients with varicose veins who underwent 57 consecutive infrainguinal vein bypass operations with PTFE reinforcement in 57 limbs. Indications for s…
Impaired Cerebrovascular Autoregulation in Large Vessel Occlusive Stroke after Successful Mechanical Thrombectomy: A Prospective Cohort Study
2020
Abstract Introduction: Successful thrombectomy improves morbidity and mortality after stroke. The present prospective, observational cohort study investigated a potential correlation between the successful restoration of tissue perfusion by mechanical thrombectomy and intact cerebrovascular autoregulation (CA). Objective: Status of CA in patients with large vessel occlusive stroke after thrombectomy. Methods: After thrombectomy CA was measured using transcranial Doppler ultrasound. For this purpose a moving correlation index (Mxa) based on spontaneous arterial blood pressure fluctuations and corresponding cerebral blood flow velocity changes was calculated. CA impairment was defined by Mxa …
Comparison between local and regional anesthesia in arteriovenous fistula creation.
2011
Purpose Assessment of the effectiveness of Brachial Plexus Block (BPB) via axillary approach compared to regional anesthesia for arteriovenous fistula surgery in patients affected by end-stage renal disease. Methods We compared forty patients randomly divided into two groups. Group A underwent BPB procedure with 15 mL ropivacaine 1% and 10 mL of saline (0.9% NaCl) via axillary approach. Group B received local anesthesia with lidocaine 2%. The forearm blood vessels were assessed by Doppler ultrasonography before and after the intervention. Results BPB performed on Group A was associated with a considerable venous dilation and a significant decrease (48.7%, P<.05) in pulsatility index (PI)…
Arterial and Venous Cerebral Blood Flow Velocities and Their Correlation in Healthy Volunteers and Traumatic Brain Injury Patients.
2020
Few studies have explored the cerebral venous compartment or the correlation between venous and arterial cerebral blood flows. We aimed to correlate cerebral blood flow velocities in the arterial (middle cerebral artery) and venous (straight sinus) compartments in healthy volunteers and traumatic brain injury (TBI) patients. In addition, we determined the normative range of these parameters.A total of 122 healthy volunteers and 95 severe TBI patients of both sexes were included and stratified into 3 age groups as follows: group 1 (aged, 18 to 44 y); group 2 (aged, 45 to 64 y); group 3 (older than 65 y). Transcranial Doppler systolic cerebral blood flow velocity, diastolic cerebral blood flo…
Transcranial Doppler sonography in dementia of Alzheimer type.
1994
The intention of this study was to examine the relation of clinical variables and cognitive dysfunction to cerebrovascular blood flow in a sample of patients with Alzheimer''s disease without any sign or symptom of cardiovascular or cerebrovascular disease. The patients met DSM-III-R criteria for dementia of Alzheimer type. Blood flow velocities in the anterior, middle (MCA) and posterior cerebral arteries were recorded using transcranial Doppler sonography. Several psychometric tests including the Mini-Mental State Examination (MMSE) were performed. The patients’ age correlated significantly with the systolic flow velocity in the left MCA (r = –0.57) explaining 24% of the total variance; t…
Photoreactive flow changes in the posterior cerebral artery in control subjects and patients with occipital lobe infarction.
1995
Background and Purpose Photoreactive flow changes of the posterior cerebral artery (PCA) in control subjects and patients with unilateral occipital lobe infarction were investigated to study the hypothesis that occipital lobe infarction of varying extent leads to a reduced visually activated flow increase in the ipsilateral PCA. Methods Maximum mean flow velocity (MFV) of the PCA was investigated by transcranial Doppler sonography after photic stimulation of the retina. Results In 25 control subjects MFV was increased by 30.6±9.7%. In 13 patients with unilateral occipital lobe infarction the ipsilateral MFV increase was significantly lower than in control subjects. Nine patients with homon…
Blood-brain barrier disruption by low-frequency ultrasound.
2006
Background and Purpose— A recent study showed a dramatic increase in cerebral hemorrhage comprising atypical locations with low-frequency ultrasound–mediated recombinant tissue plasminogen activator–thrombolysis in humans. Here, we provide a possible explanation for this phenomenon by a side effect observed in a study using the similar ultrasound device. Methods— The study was originally undertaken to investigate by transcranial Doppler sonography, positron emission tomography and perfusion MRI whether transcranial application of wide-field low-frequency ultrasound (300 kHz) improves cerebral hemodynamics in patients with cerebral small vessel disease. Results— Showing no clear positive ef…
Comparison of right ventricular longitudinal strain imaging, tricuspid annular plane systolic excursion, and cardiac biomarkers for early diagnosis o…
2012
Aims To determine the role of assessing right ventricular (RV) function, using standard echocardiography and Doppler myocardial imaging (DMI), in the early diagnosis of cardiac amyloidosis and in the prediction of mortality. Methods and results Patients with primary systemic (AL) amyloidosis seen at our institution from 1 February 2004 through 31 October 2005 (N = 249) were categorized by left ventricular thickness and E′ velocity and compared with 38 age- and sex-matched controls. Standard echocardiographic and DMI examination were used to measure echocardiographic parameters of RV function: systolic tissue velocity, strain rate, and strain were determined for basal and middle RV free wall…
Embolic stroke, sinus rhythm and left atrial mechanical function
2004
A 64-year-old man manifested a stroke two years after restoration of sinus rhythm through a radiofrequency catheter ablation. Transesophageal echo- cardiography demonstrated the presence of a thrombus in the left atrial appendage. Left atrial volumes and different parameters of atrial emptying showed that, de- spite the persistence of the sinus rhythm, atrial mechanical function was severely impaired. After atrial ablation procedures echocardiography can be useful to stratify pa- tients according to their risk of developing embolic events and hence be of help in deciding whether or not discontinuation of anticoagulant therapy is the appropri- ate choice.
Involvement of estrogen receptors in the resveratrol-mediated increase in dopamine transporter in human dopaminergic neurons and in striatum of femal…
2011
Treatment with resveratrol (RSV) has been shown to protect vulnerable neurons after various brain injuries and in neurodegenerative diseases. The mechanisms for the effects of RSV in brain are not fully understood, but RSV may affect the expression of various gene products. RSV is structurally related to the synthetic estrogen, diethylstilbestrol so the effects of RSV may be gender-specific. Here we studied the role of RSV in the regulation of dopamine transporter (DAT) in the striatum using male and female mice. The basic levels of DAT in the striatum showed no sex difference, but the levels increased significantly by RSV (20 mg/kg i.p.) in female but not in male mice. Pretreatment of mice…