The Poffenberger paradigm is a well-known measure of interhemispheric transfer delays, calculated on the basis of the crossed vs uncrossed reaction time difference (CUD). However, the proper interpretation of CUD is exte...The Poffenberger paradigm is a well-known measure of interhemispheric transfer delays, calculated on the basis of the crossed vs uncrossed reaction time difference (CUD). However, the proper interpretation of CUD is extensively debated in the literature. In this study we used connectivity measures in an attempt to interpret CUD from the perspective of functional connectivity. Accordingly, we tried to define functional couplings in the Poffenberger paradigm; we used a simple choice version of the paradigm, and included a stimulation only (SO) condition for comparison. As an index of functional coupling we employed partial directed coherence, exploiting bilateral grouping of the electrodes to compute intra-and interhemispheric connection weight ratios (CWRs). Our findings indicated modulations in functional weights in relation to the SO condition, rather than the crossed and uncrossed conditions, such that the response executed by the right hemisphere yielded a decrease in intra-, yet an increase in interhemispheric CWRs, whereas the left hemisphere interactions showed connectivity patterns similar to the SO condition irrespective of the side of movement. Overall, our results suggest modulation of connectivity in the same/similar system, which was found to be optimized, in terms of hemispheric asymmetries, to different tasks.
In recent years the cerebellum has been attributed amore important role in higher-level functions than previously believed. We examined a cohort of patients suffering from cerebellar atrophy resulting in ataxia, with two...In recent years the cerebellum has been attributed amore important role in higher-level functions than previously believed. We examined a cohort of patients suffering from cerebellar atrophy resulting in ataxia, with two main objectives: first to investigate which regions of the cerebrum were affected by the cerebellar degeneration, and second to assess whether diffusion magnetic resonance imaging (dMRI) metrics within the medial (MCP) and superior cerebellar peduncle (SCP) - namely fractional anisotropy (FA) and radial diffusivity (RD) - could be used as a biomarker in patients with this condition. Structural and dMRI data of seven patients with cerebellar atrophy (2 with spinocerebellar atrophy type 2, 1 with Friedreich's ataxia, 4 with idiopathic cerebellar ataxia) and no visible cortical lesions or cortical atrophy were investigated with Freesurfer and voxel-based morphometry (VBM) of gray matter (GM) as well as MCP and SCP FA maps. Correlations of MCP and SCP mean FA with ataxia scores and subscores were also evaluated. Freesurfer showed that patients had significantly reduced volume of the thalamus, ventral diencephalon and pallidum. VBM also demonstrated significantly lower local GM volumes in patients, notably in the head of the caudate nucleus, posterior cingulate gyrus and orbitofrontal cortex bilaterally, as well as in Broca's area in the left hemisphere, and a significant increase in RD in the MCP and SCP of both hemispheres. A significant correlation was found between MCP mean FA and total ataxia score (R=-0.7, p=0.03), and subscores for kinetic functions (R=-0.74, p=0.03) and oculomotor disorders (R=-0.70, p=0.04). The regions of the cerebrum found to have significantly lower local GM volumes have been described to be involved in higher-level cerebellar functions such as initiation of voluntary movements, emotional control, memory retrieval and general cognition. Our findings corroborate recent research pointing to a more extensive corticocerebellar system than previously thought. The significant difference in the MCP and SCP dMRI metrics between patients and controls as well as the significant correlation with ataxia total score and subscores support the use of dMRI metrics as an imaging biomarker for cerebellar degeneration and ataxia.
The identification of pathways connecting the cerebral cortex with subcortical structures is critical to understanding how large-scale brain networks operate. The cerebellum, for example, is known to project numerous axo...The identification of pathways connecting the cerebral cortex with subcortical structures is critical to understanding how large-scale brain networks operate. The cerebellum, for example, is known to project numerous axonal bundles to thecerebral cortex passing through the thalamus. This paper focuses on the technical details of cerebello-thalamo-cortical pathway reconstruction using advanced diffusion MRI techniques in humans in vivo. Pathways reconstructed using seed/target placement on super-resolution maps, created with track density imaging (TDI), were compared with those reconstructed by defining regions of interest (ROIs) on non-diffusion weighted images (b0). We observed that the reconstruction of the pathways was more anatomically accurate when using ROIs placed on TDI rather than on b0 maps, while inter-subject variability and reproducibility were similar between the two methods. Diffusion indices along pathways showed a position-dependent specificity that will need to be taken into consideration in future clinical investigations.
Quantitative magnetic resonance imaging can be combined with advanced biophysical models to measure microstructural features of white matter. Non-invasive microstructural imaging has the potential to revolutionize neuros...Quantitative magnetic resonance imaging can be combined with advanced biophysical models to measure microstructural features of white matter. Non-invasive microstructural imaging has the potential to revolutionize neuroscience, and acquiring these measures in clinically feasible times would greatly improve patient monitoring and clinical studies of drug efficacy. However, a good understanding of microstructural imaging techniques is essential to set realistic expectations and to prevent over-interpretation of results. This review explains the methodology behind microstructural modeling and imaging, and gives an overview of the breakthroughs and challenges associated with it.
Neuroimaging, both with magnetic resonance imaging (MRI) and positron emission tomography (PET), has gained a pivotal role in the diagnosis of primary neurodegenerative diseases. These two techniques are used as biomarke...Neuroimaging, both with magnetic resonance imaging (MRI) and positron emission tomography (PET), has gained a pivotal role in the diagnosis of primary neurodegenerative diseases. These two techniques are used as biomarkers of both pathology and progression of Alzheimer's disease (AD) and to differentiate AD from other neurodegenerative diseases. MRI is able to identify structural changes including patterns of atrophy characterizing neurodegenerative diseases, and to distinguish these from other causes of cognitive impairment, e.g. infarcts, space-occupying lesions and hydrocephalus. PET is widely used to identify regional patterns of glucose utilization, since distinct patterns of distribution of cerebral glucose metabolism are related to different subtypes of neurodegenerative dementia. The use of PET in mild cognitive impairment, though controversial, is deemed helpful for predicting conversion to dementia and the dementia clinical subtype. Recently, new radiopharmaceuticals for the in vivo imaging of amyloid burden have been licensed and more tracers are being developed for the assessment of tauopathies and inflammatory processes, which may underlie the onset of the amyloid cascade. At present, the cerebral amyloid burden, imaged with PET, may help to exclude the presence of AD as well as forecast its possible onset. Finally PET imaging may be particularly useful in ongoing clinical trials for the development of dementia treatments. In the near future, the use of the above methods, in accordance with specific guidelines, along with the use of effective treatments will likely lead to more timely and successful treatment of neurodegenerative dementias.
Non-invasive mapping of brain functional connectivity (FC) has played a fundamental role in neuroscience, and numerous scientists have been fascinated by its ability to reveal the brain's intricate morphology and functio...Non-invasive mapping of brain functional connectivity (FC) has played a fundamental role in neuroscience, and numerous scientists have been fascinated by its ability to reveal the brain's intricate morphology and functional properties. In recent years, two different techniques have been developed that are able to explore FC in pathophysiological conditions and to provide simple and non-invasive biomarkers for the detection of disease onset, severity and progression. These techniques are independent component analysis, which allows a network-based functional exploration of the brain, and graph theory, which provides a quantitative characterization of the whole-brain FC. In this paper we provide an overview of these two techniques and some examples of their clinical applications in the most common neurodegenerative disorders associated with cognitive decline, including mild cognitive impairment, Alzheimer's disease, Parkinson's disease, dementia with Lewy Bodies and behavioral variant frontotemporal dementia.
Hip fracture is common in the elderly and it is usually associated with comorbidities and physiological changes which may have an impact on functioning and quality of life. The concept of resilience may explain why this...Hip fracture is common in the elderly and it is usually associated with comorbidities and physiological changes which may have an impact on functioning and quality of life. The concept of resilience may explain why this impact varies among patients. The aim of this open, prospective cohort study was to explore the relationships between resilience, frailty and quality of life in orthopedic rehabilitation patients, and also to assess whether these factors might affect rehabilitation outcome. Eighty-one patients, older than 60 years, underwent a multidisciplinary assessment at the beginning and at the end of the rehabilitation period following orthopedic surgery to the lower limb. The assessments were performed using the Resilience Scale, the Multidimensional Prognostic Index (as a measure of frailty), the WHO Quality of Life-BRIEF, the Geriatric Depression Scale, and the Functional Independence Frailty and resilience in an older population. The role of resilience during rehabilitation after orthopedic surgery in geriatric patients with multiple comorbidities Measure (as a measure of the rehabilitation outcome). A negative correlation between disability and resilience emerged and this association interacted with frailty level. We also found that resilience and quality of life are positive predictors of functional status at discharge.
The purpose of this study was to quantitatively compare the effects, on walking performance, of end-effector robotic rehabilitation locomotor training versus intensive training with a treadmill in Parkinson's disease (PD...The purpose of this study was to quantitatively compare the effects, on walking performance, of end-effector robotic rehabilitation locomotor training versus intensive training with a treadmill in Parkinson's disease (PD). Fifty patients with PD were randomly divided into two groups: 25 were assigned to the robot-assisted therapy group (RG) and 25 to the intensive treadmill therapy group (IG). They were evaluated with clinical examination and 3D quantitative gait analysis [gait profile score (GPS) and its constituent gait variable scores (GVSs) were calculated from gait analysis data] at the beginning (T0) and at the end (T1) of the treatment. In the RG no differences were found in the GPS, but there were significant improvements in some GVSs (Pelvic Obl and Hip Ab-Add). The IG showed no statistically significant changes in either GPS or GVSs. The end-effector robotic rehabilitation locomotor training improved gait kinematics and seems to be effective for rehabilitation in patients with mild PD.
Takotsubo cardiomyopathy (TTS) is a peculiar clinical condition often affecting postmenopausal women after a stressful trigger. The underlying mechanisms have not been completely elucidated but several hypotheses have be...Takotsubo cardiomyopathy (TTS) is a peculiar clinical condition often affecting postmenopausal women after a stressful trigger. The underlying mechanisms have not been completely elucidated but several hypotheses have been advanced, with catecholamine cardiotoxicity, microvascular dysfunction and coronary artery spasm each suggested to play a role. The incidence of stroke after TTS appears to range from 0% to 7.7%, and interestingly TTS has been described as both a cause and a complication of stroke. We sought to assess the incidence and predictors of stroke during the index event (peri-index event stroke) in a heterogeneous TTS population. We conducted a retrospective descriptive study reviewing patients who were discharged with a diagnosis of TTS from the Einstein Medical Center, Philadelphia, PA and Danbury Hospital, Danbury, CT in the period between 2003 and 2014. A total of Incidence and predictors of stroke during the index event in an ethnically diverse Takotsubo cardiomyopathy population 206 patients met the modified Mayo Clinic criteria and were included in the study. The patients' overall mean age was 67.8 years; 87% (n=179) were females and 25% (n=53) were African Americans. The following incidence rates were found: stroke 7%, in-hospital heart failure 26.7%, and in-hospital death 7%. On multivariate analysis independent predictors (expressed as odds ratios with 95% confidence intervals) of periindex event stroke were: i) African American race (OR 3.2, 95% CI 1.2-10.2, p=0.048); ii) hypertension (OR 10.5, 95% CI 1.3-88, p=0.03). ACE inhibitor use was a protective factor for developing peri-index event stroke (OR 0.15, 95% CI 0.04-0.5, p=0.001). There was a trend towards dual antiplatelet therapy (DAPT) being protective for stroke (OR 0.3, 95% CI 0.05-1.1, p=0.08). The incidence of peri-index event stroke was 7%. African American race and hypertension were found to be independent predictors of peri-index event stroke. Prospective clinical trials are needed to confirm these findings and to better determine the impact of hypertension as a risk factor for stroke and to assess the role of DAPT in preventing it.
The New Test of Odor Pleasantness (NTOP) evaluates the hedonicity of olfactory stimulants. The aim of this study was to compare results of the NTOP, the Sniffin' Sticks test, and the Odorized Marker Test (OMT) in patient...The New Test of Odor Pleasantness (NTOP) evaluates the hedonicity of olfactory stimulants. The aim of this study was to compare results of the NTOP, the Sniffin' Sticks test, and the Odorized Marker Test (OMT) in patients with Parkinson's disease (PD). The study sample comprised 30 PD patients (mean age 71±7.36 years) and the control group made up of 31 non-PD subjects (mean age 68±12.39 years). Sociodemographic data, medical history and tests of cognitive function were investigated. Olfaction was evaluated using the NTOP, Sniffin' Sticks test and OMT. The PD patients, compared with the control group, recorded significantly lower scores on all three tests: NTOP (p=0.00), Sniffin' Sticks (p=0.02), OMT (p=0.00). The NTOP was the test preferred by 55% of the subjects. This preference was more marked in the PD group. This study shows that the NTOP is a valuable method within the complex array of olfactory screening tools used in PD.
Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by ventricular dilation accompanied by a progressive triad of a gait disturbance, "dementia" and incontinence. We retrospectively evaluated cogn...Idiopathic normal pressure hydrocephalus (iNPH) is a syndrome characterized by ventricular dilation accompanied by a progressive triad of a gait disturbance, "dementia" and incontinence. We retrospectively evaluated cognitive profile, and its relationship with disease variables, in 64 iNPH patients. The iNPH group performed significantly worse than the control group on all neuropsychological tests, except for verbal memory (within the normal range). The patients were subdivided into four groups: group 1 (42%: global cognitive impairment); group 2 (24%: frontosubcortical dysfunction); group 3 (17%: isolated deficit of a single cognitive domain); group 4 (17%: no cognitive impairment). Group 1 was older, with a significantly longer disease duration and more severe motor disease, while groups 3 and 4 were younger and presented milder motor impairment and a shorter disease duration. These data suggest parallel progression of cognitive and motor impairment in iNPH; early shunt surgery might prevent the development, in older age, of dementia in these patients.
The aim of this study was to investigate a Brazilian family carrying full penetrance alleles for Huntington's disease (HD) in order to correlate each member's genetic and clinical features. To this end, the following sca...The aim of this study was to investigate a Brazilian family carrying full penetrance alleles for Huntington's disease (HD) in order to correlate each member's genetic and clinical features. To this end, the following scales were administered in each patient: the Beck Depression Inventory, the Mini-Mental State Examination (MMSE) and the Unified Huntington's Disease Rating Scale (UHDRS). The patterns of CAG and CCG polymorphic regions in the HTT gene were determined, the disease burden score was calculated, and genotypes were correlated with phenotypes within this family. We suggest that HD duration, the number of years of formal education, and UHDRS status variables can explain 96.6% of the MMSE variability in HD patients. A strong significant correlation was found between the disease burden score and the UHDRS (r = 0.76; p-value = 0.049) and the MMSE (r = -0.90; p-value = 0.006). The correlations between CAG allele size and the three clinical evaluations performed in the HD patients were not statistically significant.
Women with epilepsy (WWE) face specific challenges throughout their lifespan due to the effects of seizures and antiepileptic drugs on hormonal function, potentially affecting both sexual and reproductive health. This re...Women with epilepsy (WWE) face specific challenges throughout their lifespan due to the effects of seizures and antiepileptic drugs on hormonal function, potentially affecting both sexual and reproductive health. This review article addresses the most common issues of practical relevance to clinicians treating WWE: epidemiology and clinical presentations (including catamenial epilepsy), contraception, reproductive and sexual dysfunction, pregnancy, lactation, menopause-related issues (including bone health), and mental health aspects. Awareness of these gender-specific issues and implementation/adaptation of effective interventions for WWE results in significantly improved health-related quality of life in this patient population.
Martino Cinnera A, Bonnì S, Iosa M
… +4 more, Ponzo V, Fusco A, Caltagirone C, Koch G
Funct Neurol
· 2016 · PMID 27358225
Multimodal treatments are emerging as effective approaches for motor recovery in traumatic brain injury (TBI). Various evidence has demonstrated that repetitive transcranial magnetic stimulation (rTMS) may improve outcom...Multimodal treatments are emerging as effective approaches for motor recovery in traumatic brain injury (TBI). Various evidence has demonstrated that repetitive transcranial magnetic stimulation (rTMS) may improve outcomes in people with motor disorders. Behavioral gains from rTMS protocols may be maximized when brain stimulation is coupled with carefully designed occupational/physical therapy. We present the case of a 25-year-old man with chronic TBI (a bilateral corticosubcortical parieto-occipital lesion) who underwent three weeks of cerebellar intermittent theta burst stimulation (iTBS), a form of rTMS, combined with neurorehabilitation treatment. The Fugl-Meyer Assessment (FMA), Berg Balance Scale (BBS), Jebsen-Taylor Hand Function Test, and accelerometer gait analysis were administered before and after treatment. The results showed improvements in balance performance (BBS: T0=47; T1=53; +10.72%), motor recovery (FMA: T0=93/100; T1=96/100; +3.00%), step length (T0=50.4±7.2; T1=53.8±2.2 cm, p<0.001), and walking speed (T0=0.87±0.06; T1=0.91±0.04 m/sec,p<0.001). Combined cerebellar rTMS and neurore-Clinical effects of non-invasive cerebellar magnetic stimulation treatment combined with neuromotor rehabilitation in traumatic brain injury. A single case study. habilitation seems to be a promising treatment for motor and balance dysfunctions in TBI patients.
Complications after unilateral acquired brain injury (ABI) can affect various areas of expertise causing (depending on the location of the lesion) impairment in occupational performance. The aim of this study was to anal...Complications after unilateral acquired brain injury (ABI) can affect various areas of expertise causing (depending on the location of the lesion) impairment in occupational performance. The aim of this study was to analyze and compare the concepts of occupational performance and functional independence, both before and after a multicomponent intervention including occupational therapy, in persons with unilateral brain damage. This was a longitudinal quasi-experimental pretest post-test study in a sample of 58 patients with unilateral brain injury (28 with traumatic brain injury and 30 with ischemic stroke). The patients' level of independence was measured using the short version of the International Classification of Functioning, Disability and Health. We also measured quality of performance using the Assessment of Motor and Process Skills. The findings of this study showed that patients with injury in the right hemisphere improved more than those with left hemisphere damage (p<0.001). All the patients with ABI, especially those with right-sided injury, derived benefit from the multicomponent intervention, except in the area of motor skills. More research is needed on the specific techniques that might address such skills.
The aim of this study was to determine cerebrospinal fluid (CSF) characteristics after an unprovoked first seizure (UFS). We reviewed the medical records of 71 patients with UFS who underwent lumbar puncture, and examine...The aim of this study was to determine cerebrospinal fluid (CSF) characteristics after an unprovoked first seizure (UFS). We reviewed the medical records of 71 patients with UFS who underwent lumbar puncture, and examined the CSF parameters. Each CSF parameter was evaluated separately for potential correlations with the other study variables. We observed an overall frequency of CSF abnormalities of 35.2%. CSF protein was the most common abnormal parameter (31%) and showed significant positive correlations with male gender (p=0.037) and older age (p=0.007). Only seven patients (9.9%) had an abnormal cell count (5-40 cells/μl). Higher CSF cell counts were found to predict a longer hospitalization period (p=0.005). No relationship with abnormal EEG findings could be established (p=0.169). This study is one of the few to evaluate postictal CSF parameters in a clinical setting, and to our knowledge the first to investigate these parameters specifically in the emergency department. The development of a rapid, easy-to-use test that does not require extensive laboratory equipment to differentiate UFS from other conditions could be of great value in everyday clinical practice.