High frequency oscillations (HFOs) are recognized as biomarkers for epileptogenic brain tissue. A remaining challenge for epilepsy surgery is the prospective classification of tissue sampled by individual electrode contacts. We analysed long-term invasive recordings of 20 consecutive patients who subsequently underwent epilepsy surgery.
View Article and Find Full Text PDFHigh frequency oscillations (HFOs, 80-500 Hz) in invasive EEG are a biomarker for the epileptic focus. Ripples (80-250 Hz) have also been identified in non-invasive MEG, yet detection is impeded by noise, their low occurrence rates, and the workload of visual analysis. We propose a method that identifies ripples in MEG through noise reduction, beamforming and automatic detection with minimal user effort.
View Article and Find Full Text PDFObjective: Fast ripples (FR, 250-500Hz) in the intraoperative corticogram have recently been proposed as specific predictors of surgical outcome in epilepsy patients. However, online FR detection is restricted by their low signal-to-noise ratio. Here we propose the integration of low-noise EEG with unsupervised FR detection.
View Article and Find Full Text PDFObjective: High frequency oscillations (HFOs) and in particular fast ripples (FRs) in the post-resection electrocorticogram (ECoG) have recently been shown to be highly specific predictors of outcome of epilepsy surgery. FR visual marking is time consuming and prone to observer bias. We validate here a fully automatic HFO detector against seizure outcome.
View Article and Find Full Text PDFObjective: The somatosensory evoked potential (SEP) elicited by median nerve stimulation consists of the N20 peak together with the concurrent high frequency oscillation (HFO, > 500 Hz). We describe the conditions for HFO detection in ECoG and scalp EEG in intraoperative recordings.
Methods: During neurosurgical interventions in six patients under propofol anesthesia, the SEP was recorded from subdural electrode strips (15 recordings) and from scalp electrodes (10/15 recordings).
Objective: We hypothesized that high frequency oscillations (HFOs) with irregular amplitude and frequency more specifically reflect epileptogenicity than HFOs with stable amplitude and frequency.
Methods: We developed a fully automatic algorithm to detect HFOs and classify them based on their morphology, with types defined according to regularity in amplitude and frequency: type 1 with regular amplitude and frequency; type 2 with irregular amplitude, which could result from filtering of sharp spikes; type 3 with irregular frequency; and type 4 with irregular amplitude and frequency. We investigated the association of different HFO types with the seizure onset zone (SOZ), resected area and surgical outcome.
Objectives: High frequency oscillations (HFOs) have been proposed as a new biomarker for epileptogenic tissue. The exact characteristics of clinically relevant HFOs and their detection are still to be defined.
Methods: We propose a new method for HFO detection, which we have applied to six patient iEEGs.
An experience with using autologous bone marrow mononuclears for regeneration of the heart was analyzed in 97 patients in whom the intracoronary transplantation of autologous mononuclear bone marrow cells was performed. The results were estimated in terms up to 5 years and compared with a group of 37 patients who underwent only conservative treatment. A distinct positive dynamic of clinical and echocardiographic indices in the main group was noted in a subgroup of patients with a decreased ejection fraction (EF less than 50%) as compared with an analogous subgroup of patients in the control group.
View Article and Find Full Text PDFVestn Khir Im I I Grek
August 2012
The main group included 17 patients with distal lesion of the coronary bed in whom the performance of complete direct myocardium revascularization was not possible. The autologous bone marrow mononuclears were administered to the main group patients at the period from 2008 to 2010. The control group consisted of 10 patients given standard medicamentous therapy.
View Article and Find Full Text PDFSince 2003 intracoronary administration of autologous bone marrow mononuclear cells has been performed in 119 patients with inoperable coronary artery disease, 53 of which had reduced ejection function that was gradually increased after injection of mononuclear bone marrow cells. By the 6th year the difference between the median of systolic and diastolic sizes of the left ventricle decreased by 12 and 14 mm respectively. In the control group the dynamics of changes of these indices at the same period was of negative character.
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