Search results for "imagin."
showing 10 items of 7170 documents
Structural brain correlates of IQ changes in bipolar disorder
2006
Background. There is increasing evidence that cognitive deficits are present in bipolar disorder (BP), but their neural correlates have not been fully explored. The aim of this study is to correlate structural brain abnormalities with cognitive performance in BP and to explore differences between clinical subtypes. Method. Thirty-six BP patients (13 men, 23 women) with a mean age of 39 years (range 21–63 years) underwent neuropsychological testing and imaging. Twenty-five patients had bipolar disorder I (BP I) and 11 had bipolar disorder II (BP II). Patients with co-morbid psychiatric diagnosis, drug and alcohol abuse or systemic illness were excluded. Correlations between cognitive perform…
Lithium prevents grey matter atrophy in patients with bipolar disorder: an international multicenter study
2020
AbstractBackgroundLithium (Li) is the gold standard treatment for bipolar disorder (BD). However, its mechanisms of action remain unknown but include neurotrophic effects. We here investigated the influence of Li on cortical and local grey matter (GM) volumes in a large international sample of patients with BD and healthy controls (HC).MethodsWe analyzed high-resolution T1-weighted structural magnetic resonance imaging scans of 271 patients with BD type I (120 undergoing Li) and 316 HC. Cortical and local GM volumes were compared using voxel-wise approaches with voxel-based morphometry and SIENAX using FSL. We used multiple linear regression models to test the influence of Li on cortical an…
[123I]IBZM SPECT in patients treated with typical and atypical neuroleptics: relationship to drug plasma levels and extrapyramidal side effects
1997
[123I]Iodobenzamide (IBZM) is an iodine-labeled dopamine receptor ligand and can be used to visualize brain D2 receptors in humans with single photon emission computerized tomography (SPECT). The ratio of striatal IBZM uptake to uptake in frontal cortex (ST/FC ratio) represents a semiquantitative measure of D2 receptor binding in the striatum. Our study sample included six patients treated with haloperidol (3.0-8.0 mg/day orally; one patient with an average of 0.9 mg/day intramuscularly), five patients with benperidol (9.0-15.0 mg/day orally) and nine patients treated with clozapine (200.0-600.0 mg/day orally). Typical neuroleptics (TNs) and atypical neuroleptics (ANs) were significantly di…
Intraoperative C-arm CT imaging in angular stable plate osteosynthesis of distal radius fractures
2013
The purpose of this study was to analyze the practicability and benefit of intraoperative C-arm computed tomography (CT) imaging in volar plate osteosynthesis of unstable distal radius fractures. During a 1 year period, intraoperative three dimensional (3D) imaging with the ARCADIS Orbic 3D was performed in addition to standard fluoroscopy in 51 cases. The volar angular stable plate oesteosyntheses were analyzed intraoperatively and, if necessary, improved immediately. The duration of the scan and radiation exposure dose were measured. On average, performance of the scan and analysis of the CT dataset took 6.7 minutes. In 31.3% of the surgeries a misplacement of screws was detected and cor…
The value of nuclear medicine for the diagnosis of spine diseases.
1993
Nuclear medicine examinations hold an important position in the diagnosis of diseases of the spine. During the last decade, decisive progress has been made in the field of instrumentation and radiopharmaceutical techniques: the use of high resolution collimators and the introduction of emission computer tomography as examples of improved instrumentation as well as 99m-Technetium red blood cell labelling as a new radiopharmaceutical technique. These present some of the developments responsible for the growing importance of scintigraphical diagnosis. Inflammatory processes of the vertebrae and the surrounding soft tissues can be detected or excluded with high reliability by the use of radionu…
Seventh nerve palsies may be the only clinical sign of small pontine infarctions in diabetic and hypertensive patients
2002
Backgroud: Small brainstem infarctions are increasingly recognized as a cause of isolated ocular motor and vestibular nerve palsies in diabetic and/or hypertensive patients. This raises the question whether there are also isolated 7th nerve palsies due to pontine infarctions in patients with such risk factors for the development of cerebrovascular diseases. Methods: Over an 11-year-period, we retrospectively identified 10 diabetic and/or hypertensive patients with isolated 7th nerve palsies and electrophysiological abnormalities indicating pontine dysfunction. All patients had examinations of masseter and blink reflexes, brainstem auditory evoked potentials, direct current electro-oculograp…
Kinesthetic motor imagery training modulates frontal midline theta during imagination of a dart throw.
2016
Motor imagery (MI) is a frequently used and effective method for motor learning in sports as well as in other domains. Electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) studies indicated that experts within a certain sport exhibit a more pronounced brain activity during MI as compared to novices. Similar to the execution, during MI the motor sequence has to be planned. Thus, the frontal attentional system, in part represented by the frontal midline theta (4-7Hz), is closely related to these processes and presumably plays a major role in MI as well. In this study, a MI dart training and its impact on frontal midline theta activity (fmt) during MI are examined. 53 …
Increased gait variability during robot-assisted walking is accompanied by increased sensorimotor brain activity in healthy people
2019
Abstract Background Gait disorders are major symptoms of neurological diseases affecting the quality of life. Interventions that restore walking and allow patients to maintain safe and independent mobility are essential. Robot-assisted gait training (RAGT) proved to be a promising treatment for restoring and improving the ability to walk. Due to heterogenuous study designs and fragmentary knowlegde about the neural correlates associated with RAGT and the relation to motor recovery, guidelines for an individually optimized therapy can hardly be derived. To optimize robotic rehabilitation, it is crucial to understand how robotic assistance affect locomotor control and its underlying brain act…
Qualitative different memory impairments across frontal lobe subgroups
2006
Recall impairments in patients with lesions to the prefrontal cortex (PFC) have variously been attributed to problems with organisation at encoding, organisation at retrieval and monitoring at retrieval. Neuroimaging and recent theoretical work has associated the left lateral PFC with organisation and strategy production at encoding, and the right lateral PFC with organisation, error detection and monitoring at retrieval. However few lesion studies have been anatomically specific enough to test the direct predictions made by this work. Proactive interference, response to prompting, monitoring and organisational strategies were examined in 34 patients with frontal lobe lesions and 50 healthy…
Brain Function and Upper Limb Outcome in Stroke: A Cross-Sectional fMRI Study
2015
Objective The nature of changes in brain activation related to good recovery of arm function after stroke is still unclear. While the notion that this is a reflection of neuronal plasticity has gained much support, confounding by compensatory strategies cannot be ruled out. We address this issue by comparing brain activity in recovered patients 6 months after stroke with healthy controls. Methods We included 20 patients with upper limb paresis due to ischemic stroke and 15 controls. We measured brain activation during a finger flexion-extension task with functional MRI, and the relationship between brain activation and hand function. Patients exhibited various levels of recovery, but all we…