Search results for " Map"
showing 10 items of 2344 documents
Erfassung von Neurotransmitterinteraktionen mit PET und SPECT durch pharmakologische Challenge-Paradigmen
2000
Functional brain imaging with positron emission tomography (PET) and single photon emission computerized tomography (SPECT) enables the in vivo study of specific neurochemical processes in the context of normal regulatory mechanisms and pathophysiological alterations of the brain. By combining these methods with pharmacological challenge-paradigms, the study of functional interactions of different neurotransmitter systems is possible. This review will present data from animal and healthy volunteer studies as well as first data from investigations in different patient populations with regard to this research direction. Especially, interactions of different neurotransmitter systems with the d…
Mathematical Modeling for Neuropathic Pain: Bayesian Linear Regression and Self-Organizing Maps Applied to Carpal Tunnel Syndrome
2020
A better understanding of the connection between risk factors associated with pain and function may assist therapists in optimizing therapeutic programs. This study applied mathematical modeling to analyze the relationship of psychological, psychophysical, and motor variables with pain, function, and symptom severity using Bayesian linear regressions (BLR) and self-organizing maps (SOMs) in carpal tunnel syndrome (CTS). The novelty of this work was a transfer of the symmetry mathematical background to a neuropathic pain condition, whose symptoms can be either unilateral or bilateral. Duration of symptoms, pain intensity, function, symptom severity, depressive levels, pinch tip grip force, a…
Non-invasive Spatial Mapping of Frequencies in Atrial Fibrillation: Correlation With Contact Mapping
2021
[EN] Introduction: Regional differences in activation rates may contribute to the electrical substrates that maintain atrial fibrillation (AF), and estimating them non-invasively may help guide ablation or select anti-arrhythmic medications. We tested whether non-invasive assessment of regional AF rate accurately represents intracardiac recordings. Methods: In 47 patients with AF (27 persistent, age 63 +/- 13 years) we performed 57-lead non-invasive Electrocardiographic Imaging (ECGI) in AF, simultaneously with 64-pole intracardiac signals of both atria. ECGI was reconstructed by Tikhonov regularization. We constructed personalized 3D AF rate distribution maps by Dominant Frequency (DF) ana…
Risk Stratification by nrTMS Language Mapping
2017
Resecting language-eloquent brain lesions is a major challenge in neurosurgery since we need to weight the risks of worsening the patients’ functional integrity and achieving a maximum safe resection. Although relevant functional brain structures can be identified intraoperatively by direct cortical mapping during awake surgery, a preoperative identification of functional anatomy is recommended in order to gauge surgical risks, evaluate resectability, plan the surgical approach, and identify potential starting points for intraoperative stimulation mapping.
Recurrence quantification analysis as a tool for complex fractionated atrial electrogram discrimination
2012
International audience; Atrial fibrillation is the most encountered pathology of the heart rate. The reasons of its occurrence and its particular characteristics remain unknown, resulting from complex phenomena interaction. From these interactions emerges Complex Fractionated Atrial Electrograms (CFAE) which are useful for the ablation procedure. This study presents a method based on nonlinear data analysis, the Recurrence Quantification Analysis (RQA) applied on intracardiac atrial electrograms to detect CFAE particularities. The results obtained on areas previously tagged by a cardilogist show a good sensitivity to CFAE. Combination of RQA features offers a larger discrimination potential…
A topodiagnostic investigation on body lateropulsion in medullary infarcts.
2005
Body lateropulsion may occur without signs of vestibular dysfunction and vestibular nucleus involvement. The authors examined 10 such patients with three-dimensional brainstem mapping. Body lateropulsion without limb ataxia reflected an impairment of vestibulospinal postural control caused by a lesion of the descending lateral vestibulospinal tract, whereas body lateropulsion with limb ataxia was probably the consequence of impaired or absent proprioceptive information caused by a lesion of the ascending dorsal spino-cerebellar tract.
Visual mismatch negativity for changes in orientation - a sensory memory-dependent response
2008
It remains unclear whether the mismatch negativity of event-related potentials (ERPs) in vision resembles its auditory counterpart in terms of memory relatedness. We recorded ERPs to visual bars in adult humans engaged in an auditory task. In one condition, a bar ('standard') repeated at 400- or 1100-ms non-stimulated intervals was rarely (P = 0.1) replaced by another bar of a different orientation ('deviant'). In the other condition (400-ms intervals), the occurrences of the standards were replaced by 10 (P = 0.1 each) bars of different orientations, including that of the deviant ('control-deviant'). Deviants shifted ERPs towards negative polarity relative to standards in occipital electro…
Mapping of the human visual cortex using image-guided transcranial magnetic stimulation
2002
We describe a protocol using transcranial magnetic stimulation (TMS) to systematically map the visual sensations induced by focal and non-invasive stimulation of the human occipital cortex. TMS is applied with a figure of eight coil to 28 positions arranged in a 2x2-cm grid over the occipital area. A digitizing tablet connected to a PC computer running customized software, and audio and video recording are used for detailed and accurate data collection and analysis of evoked phosphenes. A frameless image-guided neuronavigational device is used to describe the position of the actual sites of the stimulation coils relative to the cortical surface. Our results show that TMS is able to elicit p…
Indocyanine Green-Enhanced Colorectal Surgery—between Being Superfluous and Being a Game-Changer
2020
Nowadays, surgical innovations incorporate new technological conquests and must be validated by evidence-based medicine. The use of augmented reality-assisted indocyanine green (ICG) fluorescence has generated a myriad of intraoperative applications such as demonstration of key anatomical landmarks, sentinel lymph nodes, and real-time assessment of local blood flow. This paper presents a systematic review of the clinical evidence regarding the applications of ICG near-infrared (NIR) fluorescence in colorectal surgery. After we removed duplicate publications and screened for eligibility, a total of 36 articles were evaluated: 23 on perfusion assessment, 10 on lymph node mapping, and 3 on int…
Innovation in Neurosurgery: The Concept of Cognitive Mapping
2019
In recent years, advances in cortical-subcortical mapping, intraoperative neurophysiology, and neuropsychology have increased the ability to remove intrinsic brain tumors, expanding indications and maximizing the extent of resection. This has provided a significant improvement in progression-free survival, time of malignant transformation (in low-grade gliomas), and overall survival. Although current techniques enable preservation of language and motor functions during surgery, the maintenance of a complex set of functions defined with the term cognition is not always achievable. Cognition is defined as every neural process underlying a high human function and includes motor haptic and visu…