Pain Pract
February 2025
Objectives: In this study, the spread of methylene blue was compared between an ultrasound-guided Pericapsular Nerve Group (PENG) block and a double injection technique, where the approach towards the inferomedial acetabulum was added to the latter.
Methods: The two techniques were performed in 11 fresh frozen cadavers. The spread was measured after anatomical dissection in which the supplying femoral and obturator nerves were identified.
Purpose To gain more insight into the pathophysiological mechanisms of visual hallucinations (VHs) in patients with Parkinson disease (PD) by analyzing whole-brain resting-state functional connectivity in PD patients with VH (hereafter, referred to as PD + VH patients) and without VH (hereafter, referred to as PD - VH patients) and control participants. Materials and Methods For this retrospective study, 15 PD + VH patients, 40 PD - VH patients, and 15 control participants from a prospective cohort study were included, which was approved by the local ethics board and written informed consent was obtained from all participants. Functional connectivity was calculated between 47 regions of interests, of which whole-brain and region-specific means were compared by using a general linear model with false discovery rate control for multiple comparisons.
View Article and Find Full Text PDFDamage to fiber tracts connecting the nucleus basalis of Meynert (NBM) to the cerebral cortex may underlie the development of visual hallucinations (VH) in Parkinson's disease (PD), possibly due to a loss of cholinergic innervation. This was investigated by comparing structural connectivity of the NBM using diffusion tensor imaging in 15 PD patients with VH (PD + VH), 40 PD patients without VH (PD - VH), and 15 age- and gender-matched controls. Fractional anisotropy (FA) and mean diffusivity (MD) of pathways connecting the NBM to the whole cerebral cortex and of regional NBM fiber tracts were compared between groups.
View Article and Find Full Text PDFObjective: The pathophysiological mechanisms underlying Parkinson's disease (PD)-related cognitive decline and conversion to PD dementia are poorly understood. In the healthy human brain, stable patterns of posterior-to-anterior cortical information flow have recently been demonstrated in the higher frequency bands using magnetoencephalography (MEG). In this study we estimated PD-related changes in information flow patterns, as well as the contribution of subcortical regions.
View Article and Find Full Text PDFObjective: To evaluate fMRI whole-brain resting-state functional connectivity changes in relation to cognitive decline in Parkinson disease (PD) over a 3-year period.
Methods: Resting-state fMRI scans were acquired in 55 patients with PD (mean age 65.8 years, SD 6.
Objective: To assess the ability of neurophysiologic markers in conjunction with cognitive assessment to improve prediction of progression to dementia in Parkinson disease (PD).
Methods: Baseline cognitive assessments and magnetoencephalographic recordings from 63 prospectively included PD patients without dementia were analyzed in relation to PD-related dementia (PDD) conversion over a 7-year period. We computed Cox proportional hazard models to assess the risk of converting to dementia conveyed by cognitive and neurophysiologic markers in individual as well as combined risk factor analyses.
Although alterations in resting-state functional connectivity between brain regions have previously been reported in Parkinson's disease, the spatial organization of these changes remains largely unknown. Here, we longitudinally studied brain network topology in Parkinson's disease in relation to clinical measures of disease progression, using magnetoencephalography and concepts from graph theory. We characterized whole-brain functional networks by means of a standard graph analysis approach, measuring clustering coefficient and shortest path length, as well as the construction of a minimum spanning tree, a novel approach that allows a unique and unbiased characterization of brain networks.
View Article and Find Full Text PDFThe assessment of resting-state functional connectivity has become an important tool in studying brain disease mechanisms. Here we use magnetoencephalography to longitudinally evaluate functional connectivity changes in relation to clinical measures of disease progression in Parkinson's disease (PD). Using a source-space based approach with detailed anatomical mapping, functional connectivity was assessed for temporal, prefrontal and high order sensory association areas known to show neuropathological changes in early clinical disease stages.
View Article and Find Full Text PDFThe pathophysiological mechanisms of Parkinson's disease (PD)-related dementia (PDD) are still poorly understood. Previous studies using electroencephalography (EEG) and magnetoencephalography (MEG) have demonstrated widespread slowing of oscillatory brain activity as a neurophysiological characteristic of PD-related dementia. Here, we use MEG to longitudinally study early changes in oscillatory brain activity in initially nondemented PD patients that may be associated with cognitive decline.
View Article and Find Full Text PDFThe aim of the present study was to analyze resting-state brain activity in patients with Parkinson's disease (PD), a degenerative disorder of the nervous system. Magnetoencephalography (MEG) signals were recorded with a 151-channel whole-head radial gradiometer MEG system in 18 early-stage untreated PD patients and 20 age-matched control subjects. Artifact-free epochs of 4 s (1250 samples) were analyzed with Lempel-Ziv complexity (LZC), applying two- and three-symbol sequence conversion methods.
View Article and Find Full Text PDFBackground: Obesity is not only associated with metabolic abnormalities, but also with cognitive dysfunction and changes in the central nervous system. The present pilot study was carried out to investigate functional connectivity in obese and non-obese adolescents using magnetoencephalography (MEG).
Methodology/principal Findings: Magnetoencephalographic recordings were performed in 11 obese (mean BMI 38.