Association Between Flow Acceleration in the Carotid Artery and Intracranial Aneurysms.

Objectives: In physiologic pulsatile flow, velocity acceleration is an independent factor determining wall shear stress experienced by the vascular endothelium. The purpose of this study was to evaluate Doppler indices of systolic velocity acceleration in extracranial cerebral vessels and the occurrence of intracranial aneurysms.

Methods: We reviewed medical records and 3.

The neural correlates of perceived energy levels in older adults with late-life depression.

Late-life depression is common among older adults. Although white-matter abnormality is highly implicated, the extent to which the corticospinal tract is associated with the pathophysiology of late-life depression is unclear. The current study aims to investigate the white-matter structural integrity of the corticospinal tract and determine its cognitive and functional correlates in older adults with late-life depression.

The relationships between brain structural changes and perceived loneliness in older adults suffering from late-life depression.

Objective: Late-life depression is a significant health risk factor for older adults, part of which is perceived loneliness. In this voxel-based morphometry study, we examined the relationships between perceived loneliness and depression recurrence.

Methods: Fifty-two older adults were recruited, and they were split into 3 groups: single episode, multiple episodes, or normal control groups, according to their clinical histories.

Dual-phase F-florbetapir positron emission tomography in patients with primary progressive aphasia, Alzheimer's disease, and healthy controls: A preliminary study.

Background/purpose: To determine whether dual-phase F-florbetapir positron emission tomography imaging with perfusion-like and amyloid deposition information can distinguish among primary progressive aphasia (PPA), Alzheimer's disease (AD), and healthy controls (HCs).

Methods: Patients diagnosed with PPA, including four semantic dementia (SD) and two progressive nonfluent aphasia (PNFA), as well as one logopenic variant (LV) of PPA, were studied. All PPA patients, and age-/sex-matched patients with probable AD (n=8) and HCs (n=8) were subjected to dual-phase F-florbetapir imaging.

Digit symbol substitution test score and hyperhomocysteinemia in older adults.

Mounting evidence shows that hyperhomocysteinemia is a risk factor for cognitive decline. This study enrolled subjects with normal serum levels of B12 and folate and performed thorough neuropsychological assessments to illuminate the independent role of homocysteine on cognitive functions.Participants between ages 50 and 85 were enrolled with Modified Hachinski ischemic score of <4, adequate visual and auditory acuity to allow neuropsychological testing, and good general health.

Neural correlates of motor recovery after robot-assisted stroke rehabilitation: a case series study.

Robot-assisted bilateral arm therapy (RBAT) has shown promising results in stroke rehabilitation; however, connectivity mapping of the sensorimotor networks after RBAT remains unclear. We used fMRI before and after RBAT and a dose-matched control intervention (DMCI) to explore the connectivity changes in 6 subacute stroke patients. Sensorimotor functions improved in the RBAT and DMCI groups after treatment.

Alterations of diffusion tensor MRI parameters in the brains of patients with Parkinson's disease compared with normal brains: possible diagnostic use.

Objectives: To investigate the diagnostic performance of diffusion tensor imaging in patients with Parkinson's disease (PD).

Methods: We examined a total of 126 PD patients (68 males/58 females, mean age: 62.0 ±7.

Neuroplastic changes in resting-state functional connectivity after stroke rehabilitation.

Most neuroimaging research in stroke rehabilitation mainly focuses on the neural mechanisms underlying the natural history of post-stroke recovery. However, connectivity mapping from resting-state fMRI is well suited for different neurological conditions and provides a promising method to explore plastic changes for treatment-induced recovery from stroke. We examined the changes in resting-state functional connectivity (RS-FC) of the ipsilesional primary motor cortex (M1) in 10 post-acute stroke patients before and immediately after 4 weeks of robot-assisted bilateral arm therapy (RBAT).

Human amygdala activation by the sound produced during dental treatment: A fMRI study.

During dental treatments, patients may experience negative emotions associated with the procedure. This study was conducted with the aim of using functional magnetic resonance imaging (fMRI) to visualize cerebral cortical stimulation among dental patients in response to auditory stimuli produced by ultrasonic scaling and power suction equipment. Subjects (n = 7) aged 23-35 years were recruited for this study.

A simple method to improve the quality of diffusion-weighted magnetic resonance imaging with rapid histologic correlation in a murine model.

Diffusion-weighted magnetic resonance imaging (DW-MRI) has been used extensively in biomedical research. However, this technique has often suffered from distortion artifacts because of the magnetic field inhomogeneity surrounding the tissues. Histology is important for validating MRI interpretations, but correlating MRIs with tissue samples is challenging.

Magnetic-resonance imaging for kinetic analysis of permeability changes during focused ultrasound-induced blood-brain barrier opening and brain drug delivery.

Focused ultrasound (FUS) with the presence of microbubbles has been shown to induce transient and local opening of the blood-brain barrier (BBB) for the delivery of therapeutic molecules which normally cannot penetrate into the brain. The success of FUS brain-drug delivery relies on its integration with in-vivo imaging to monitor kinetic change of therapeutic molecules into the brain. In this study, we developed a dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) technique for kinetic analysis of delivered molecules during FUS-BBB opening.

Tract-based spatial statistics: application to mild cognitive impairment.

Rationale And Objectives: The primary objective of the current investigation was to characterize white matter integrity in different subtypes of mild cognitive impairment (MCI) using tract-based spatial statistics of diffusion tensor imaging.

Materials And Methods: The study participants were divided into 4 groups of 30 subjects each as follows: cognitively healthy controls, amnestic MCI, dysexecutive MCI, and Alzheimer's disease (AD). All subjects underwent a comprehensive neuropsychological assessment, apolipoprotein E genotyping, and 3-tesla MRI.

Impact of coexisting coronary artery disease on the occurrence of cerebral ischemic lesions after carotid stenting.

Background: Coronary artery disease (CAD) may coexist with extracranial carotid artery stenosis (ECAS), but the influence of CAD on procedure-related complications after carotid artery stenting (CAS) has not been well investigated. The study aimed to determine the impact of CAD on the occurrence of peri-CAS cerebral ischemic lesions on diffusion-weighted imaging (DWI) scanning.

Methods: Coronary angiography was performed within six months before CAS.

Sex dimorphism of cortical water diffusion in normal aging measured by magnetic resonance imaging.

Background: The purpose of this study was to examine sex dimorphism in water diffusion in the brain throughout the normal aging process by magnetic resonance imaging.

Methods: Diffusion-weighted images covering the majority of the brain were acquired from 77 healthy participants. Both the mean water diffusivity and diffusion kurtosis were calculated from the cortical regions and parcellated according to the template in anatomical automatic labeling.

Increased brain amyloid deposition in patients with a lifetime history of major depression: evidenced on 18F-florbetapir (AV-45/Amyvid) positron emission tomography.

Purpose: The literature suggests that a history of depression is associated with an increased risk of developing Alzheimer's disease (AD). The aim of this study was to examine brain amyloid accumulation in patients with lifetime major depression using (18)F-florbetapir (AV-45/Amyvid) PET imaging in comparison with that in nondepressed subjects.

Methods: The study groups comprised 25 depressed patients and 11 comparison subjects who did not meet the diagnostic criteria for AD or amnestic mild cognitive impairment.

Discrimination between Alzheimer's disease and mild cognitive impairment using SOM and PSO-SVM.

In this study, an MRI-based classification framework was proposed to distinguish the patients with AD and MCI from normal participants by using multiple features and different classifiers. First, we extracted features (volume and shape) from MRI data by using a series of image processing steps. Subsequently, we applied principal component analysis (PCA) to convert a set of features of possibly correlated variables into a smaller set of values of linearly uncorrelated variables, decreasing the dimensions of feature space.

Regional amyloid deposition in amnestic mild cognitive impairment and Alzheimer's disease evaluated by [18F]AV-45 positron emission tomography in Chinese population.

Background: To compare the neocortical amyloid loads among cognitively normal (CN), amnestic mild cognitive impairment (aMCI), and Alzheimer's disease (AD) subjects with [(18)F]AV-45 positron emission tomography (PET).

Materials And Methods: [(18)F]AV-45 PET was performed in 11 CN, 13 aMCI, and 12 AD subjects to compare the cerebral cortex-to-whole cerebellum standard uptake value ratios (SUVRs) of global and individual volumes of interest (VOIs) cerebral cortex. The correlation between global cortical [(18)F]AV-45 SUVRs and Mini-Mental State Examination (MMSE) scores was analyzed.

A comparison of benign and inflammatory manifestations of Tolosa-Hunt syndrome.

Background: Tolosa-Hunt syndrome (THS) manifests as a benign or an inflammatory type disease. The nosography differences between these types remain to be elucidated. We aimed to analyze and compare the clinical presentations of benign and inflammatory THS.

Noninvasive monitoring of microvascular changes with partial irradiation using dynamic contrast-enhanced and blood oxygen level-dependent magnetic resonance imaging.

Purpose: The microvasculature of a tumor plays an important role in its response to radiation therapy. Dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) and blood oxygen level-dependent (BOLD) MRI are both sensitive to vascular characteristics. The present study proposed a partial irradiation approach to a xenograft tumor to investigate the intratumoral response to radiation therapy using DCE and BOLD MRI.

Abnormal neural activity in partially remitted late-onset depression: an fMRI study of one-back working memory task.

Only half of the geriatric patients with major depressive disorder (MDD) can reach full remission after treatment of half a year. This study was designed to examine the neural responses in the partial responders of late-onset MDD. We used 3-Tesla functional magnetic resonance imaging to assess the patterns of cerebral activation/deactivation in the performance of a one-back version of the n-back working memory task.

Effect of growth hormone therapy on Taiwanese children with growth hormone deficiency.

Background/purpose: Human growth hormone (GH) has been successfully used in children with GH deficiency (GHD). However, there are few published data on the effect of GH in Taiwanese children with GHD.

Methods: We performed a retrospective cohort study to identify factors influencing the effect of GH therapy on ethnic Chinese children with GHD in Taiwan.

Seizures and multiple sclerosis in Chinese patients: a clinical and magnetic resonance imaging study.

Purpose: Epileptic seizures in Chinese patients with multiple sclerosis (MS) have not been studied extensively. We investigated the clinical, laboratory, and imaging findings for Chinese patients with MS who had experienced seizures.

Methods: A total of 93 (57.

Cortical involvement in a gait-related imagery task: comparison between Parkinson's disease and normal aging.

Purpose: We employed imaginary tasks to investigate the neurophysiology of gait in patients with Parkinson's disease (PD) using functional magnetic resonance imaging (fMRI).

Methods: Cortical activation of gait-related imagery was explored in 13 PD patients, 13 age-matched controls (Old), and 14 young volunteers (Young) using fMRI. The tasks included gait initiation, stepping over an obstacle and gait termination using an event-related design.

Blind estimation of the arterial input function in dynamic contrast-enhanced MRI using purity maximization.

Uncertainty in arterial input function (AIF) estimation is one of the major errors in the quantification of dynamic contrast-enhanced MRI. A blind source separation algorithm was proposed to determine the AIF by selecting the voxel time course with maximum purity, which represents a minimal contamination from partial volume effects. Simulations were performed to assess the partial volume effect on the purity of AIF, the estimation accuracy of the AIF, and the influence of purity on the derived kinetic parameters.

Periventricular nodular heterotopia and cardiovascular defects.

Background: Periventricular nodular heterotopia (PNH) is a rare congenital anomaly of the brain presenting as nodular heterotopia along the paraventricular region. Ten cases of PNH complicated by aortic aneurysm have been reported in the literature, and 9 of them also had symptoms of Ehlers-Danlos syndrome (EDS). This study investigated the association of PNH and cardiovascular anomalies in Asians.