Search results for "Transcranial Doppler"
showing 4 items of 34 documents
Use of middle cerebral velocity and blood pressure for the analysis of cerebral autoregulation at various frequencies: The coherence index
1998
A common component in many protocols for the evaluation of cerebral autoregulation is the comparison of transcranial Doppler ultrasound (TCD) velocities with blood pressure recordings, in which correlations between these two signals correspond to impaired autoregulation. With long data sets and complicated paradigms, however, visual inspection alone cannot adequately distinguish random coincidence from consistent correlation in a statistically valid fashion. We suggest and illustrate the use of the coherence index for this purpose. To illustrate this technique, long-term recordings of TCD velocity and blood pressure were obtained from 6 normal subjects and using 23 data segments from 8 pati…
The percutaneous treatment of Patent Foramen Ovale, an effective and safe therapeutic choice
2013
Introduction: The aim of our study is to evaluate the feasibility, safety and efficacy of the percutaneous closure of PFO (abnormal communication between the right and left atrium). Methods: Between July 2009 and October 2012 percutaneous closure was performed in 37 patients. The presence of PFO was diagnosed through the use of ultrasound techniques: transcranial doppler with contrast (cTCD), transthoracic echocardiography(TTE) and transesophageal echocardiography (TEE). Follow-up was composed consisted of a Holter ECG 7 days after the closure with a 24 hour heart rhythm monitoring, to evaluate eventual arrhythmia cases and programmed controls which included a TTE at 1-3 months, TTE+ cTCD a…
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. …