Parkinson's disease (PD) is a prevalent neurodegenerative disorder characterized by both motor and non-motor symptoms, many of which are resistant to currently available treatments. Since the discovery that non-invasive transcranial magnetic stimulation (TMS) can cause dopamine release in PD patients, there has been growing interest in the use of TMS to fill existing gaps in the treatment continuum for PD. This review evaluates the safety and efficacy of a unique multifocal, bilateral Deep TMS protocol, which has been evaluated as a tool to address motor and non-motor symptoms of PD.
View Article and Find Full Text PDFThere is growing interest in accelerated rTMS dosing regimens, wherein multiple sessions of rTMS are applied per day. This Phase IV study evaluated the safety, efficacy, and durability of various accelerated Deep TMS protocols used in clinical practice. Data were aggregated from 111 patients with major depressive disorder (MDD) at 4 sites.
View Article and Find Full Text PDFPhase IV study evaluated Deep TMS for major depression in community settings. Data were aggregated from 1753 patients at 21 sites, who received Deep TMS (high frequency or iTBS) using the H1 coil. Outcome measures varied across subjects and included clinician-based scales (HDRS-21) and self-assessment questionnaires (PHQ-9, BDI-II).
View Article and Find Full Text PDFPrevious investigation of cognitive processes using transcranial magnetic stimulation (TMS) have explored the response to different stimulation parameters such as frequency and coil location. In this study, we attempt to add another parameter by exploiting the spatial profiles of TMS coils to infer regional information concerning reward-related behavior. We used different TMS coils to modulate activity in the prefrontal cortex (PFC) and examined resulting changes in behavior and associated brain activity.
View Article and Find Full Text PDFTranscranial magnetic stimulation (TMS) is a non-invasive technique that has shown high efficacy in the treatment of major depressive disorder (MDD) and is increasingly utilized for various neuropsychiatric disorders. However, conventional TMS is limited to activating only a small fraction of neurons that have components parallel to the induced electric field. This likely contributes to the significant variability observed in clinical outcomes.
View Article and Find Full Text PDFThe FDA cleared deep transcranial magnetic stimulation (Deep TMS) with the H7 coil for obsessive-compulsive disorder (OCD) treatment, following a double-blinded placebo-controlled multicenter trial. Two years later the FDA cleared TMS with the D-B80 coil on the basis of substantial equivalence. In order to investigate the induced electric field characteristics of the two coils, these were placed at the treatment position for OCD over the prefrontal cortex of a head phantom, and the field distribution was measured.
View Article and Find Full Text PDF(1) Background: While the therapeutic efficacy of Transcranial Magnetic Stimulation (TMS) for major depressive disorder (MDD) is well established, less is known about the technique's efficacy for treating comorbid anxiety. (2) Methods: Data were retrospectively analyzed from randomized controlled trials (RCTs) that used Deep TMS with the H1 Coil for MDD treatment. The primary endpoint was the difference relative to sham treatment following 4 weeks of stimulation.
View Article and Find Full Text PDFBackground: Transcranial magnetic stimulation (TMS) is a rapidly expanding technology utilized in research and neuropsychiatric treatments. Yet, conventional TMS configurations affect primarily neurons that are aligned parallel to the induced electric field by a fixed coil, making the activation orientation-specific. A novel method termed rotational field TMS (rfTMS), where two orthogonal coils are operated with a 90° phase shift, produces rotation of the electric field vector over almost a complete cycle, and may stimulate larger portion of the neuronal population within a given brain area.
View Article and Find Full Text PDFHigh-frequency repeated transcranial magnetic stimulation (rTMS) as a treatment for major depressive disorder (MDD) has received FDA clearance for both the figure-of-8 coil (figure-8 coil) and the H1 coil. The FDA-cleared MDD protocols for both coils include high frequency (10-18 Hz) stimulation targeting the dorsolateral prefrontal cortex (dlPFC) at an intensity that is 120% of the right-hand resting motor threshold. Despite these similar parameters, the two coils generate distinct electrical fields (e-fields) which result in differences in the cortical stimulation they produce.
View Article and Find Full Text PDFUnlabelled: The blood-brain barrier is a highly selective anatomical and functional interface allowing a unique environment for neuro-glia networks. Blood-brain barrier dysfunction is common in most brain disorders and is associated with disease course and delayed complications. However, the mechanisms underlying blood-brain barrier opening are poorly understood.
View Article and Find Full Text PDFHuman proprioception is essential for motor control, yet its central processing is still debated. Previous studies of passive movements and illusory vibration have reported inconsistent activation patterns related to proprioception, particularly in high-order sensorimotor cortices. We investigated brain activation specific to proprioception, its laterality, and changes following stroke.
View Article and Find Full Text PDFBackground: Currently available TMS stimulators have a single channel operating a single coil.
Objective: To outline and present physical and physiological benefits of a novel convenient multi-channel stimulator, comprising five channels, where the stimulation parameters of each channel are independently controllable.
Methods: Simultaneous and sequential operation of various channels was tested in healthy volunteers.
Objective: To compare the ability of an H-coil and figure-8 coil to stimulate different motor cortex regions.
Methods: The resting (rMT) and active (aMT) motor thresholds were measured for the right hand APB and leg AHB muscles in 10 subjects, using an H-coil and a figure-8 coil. The electric field distribution induced by the coils was measured in a head model.
Fluids Barriers CNS
February 2013
The blood-brain barrier (BBB) is a functional and structural barrier separating the intravascular and neuropil compartments of the brain. It characterizes the vascular bed and is essential for normal brain functions. Dysfunction in the BBB properties have been described in most common neurological disorders, such as stroke, traumatic injuries, intracerebral hemorrhage, tumors, epilepsy and neurodegenerative disorders.
View Article and Find Full Text PDFPurpose: To measure renal adenosine triphosphate (ATP) (bioenergetics) during hypotensive sepsis with or without angiotensin II (Ang II) infusion.
Methods: In anaesthetised sheep implanted with a renal artery flow probe and a magnetic resonance coil around one kidney, we induced hypotensive sepsis with intravenous Escherichia coli injection. We measured mean arterial pressure (MAP), heart rate, renal blood flow RBF and renal ATP levels using magnetic resonance spectroscopy.
Objective: 2 Childhood-onset type 1 diabetes is associated with neurocognitive deficits, but there is limited evidence to date regarding associated neuroanatomical brain changes and their relationship to illness variables such as age at disease onset. This report examines age-related changes in volume and T2 relaxation time (a fundamental parameter of magnetic resonance imaging that reflects tissue health) across the whole brain.
Research Design And Methods: Type 1 diabetes, N = 79 (mean age 20.
Objectives: To investigate if low-dose lithium may counteract the microstructural and metabolic brain changes proposed to occur in individuals at ultra-high risk (UHR) for psychosis.
Methods: Hippocampal T2 relaxation time (HT2RT) and proton magnetic resonance spectroscopy ((1)H-MRS) measurements were performed prior to initiation and following three months of treatment in 11 UHR patients receiving low-dose lithium and 10 UHR patients receiving treatment as usual (TAU). HT2RT and (1)H-MRS percentage change scores between scans were compared using repeated measures ANOVA and correlated with behavioural change scores.
We highlight a fundamental difference between voxel-based methods that interrogate signal intensity directly and those that interrogate morphometric features; we discuss how signal intensity changes might erroneously affect morphometric measures, and we provide some guidance for selection of appropriate methods to address particular hyphotheses. Our discussion is motivated by a recent application of voxel-based morphometry methods to T2-weighted images (T2-Voxel Based Morphometry; T2-VBM). In this context we discuss alternative approaches including Voxel-Based T2-Relaxometry (VBR) and Voxel Based Iterative Sensitivity analysis of T2-Weighted Images (VBIS-T2).
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