3-T MR-guided focused ultrasound thalamotomy for tremor in patients with a cardiac pacemaker: case series and review of the literature.

MR-guided focused ultrasound (MRgFUS) has proven its efficacy and safety for the treatment of essential tremor (ET) and/or Parkinson's disease (PD). However, having a cardiac pacemaker has been considered an exclusion criterion for the use of MRgFUS. Only 2 patients with a cardiac pacemaker treated with MRgFUS have been previously reported, both treated using 1.

Magnetic Resonance-Guided Focused Ultrasound (MRgFUS)-Thalamotomy for Essential Tremor: Lesion Location and Clinical Outcomes.

Background: Factors predicting clinical outcomes after MR-guided focused ultrasound (MRgFUS)-thalamotomy in patients with essential tremor (ET) are not well known.

Objective: To examine the clinical outcomes and their relationship with patients' baseline demographic and clinical features and lesion characteristics at 6-month follow-up in ET patients.

Methods: A total of 127 patients were prospectively evaluated at 1 (n = 122), 3 (n = 102), and 6 months (n = 78) after MRgFUS-thalamotomy.

Astrogliosis in aging and Parkinson's disease dementia: a new clinical study with C-BU99008 PET.

The role of astrogliosis in the pathology of brain aging and neurodegenerative diseases has recently drawn great attention. Imidazoline-2 binding sites represent a possible target to map the distribution of reactive astrocytes. In this study, we use C-BU99008, an imidazoline-2 binding sites-specific PET radioligand, to image reactive astrocytes in healthy controls and patients with established Parkinson's disease dementia.

Multimodal brain and retinal imaging of dopaminergic degeneration in Parkinson disease.

Parkinson disease (PD) is a progressive disorder characterized by dopaminergic neurodegeneration in the brain. The development of parkinsonism is preceded by a long prodromal phase, and >50% of dopaminergic neurons can be lost from the substantia nigra by the time of the initial diagnosis. Therefore, validation of in vivo imaging biomarkers for early diagnosis and monitoring of disease progression is essential for future therapeutic developments.

Neuromelanin-MRI to Quantify and Track Nigral Depigmentation in Parkinson's Disease: A Multicenter Longitudinal Study Using Template-Based Standardized Analysis.

Background: Clinical diagnosis and monitoring of Parkinson's disease (PD) remain challenging because of the lack of an established biomarker. Neuromelanin-magnetic resonance imaging (NM-MRI) is an emerging biomarker of nigral depigmentation indexing the loss of melanized neurons but has unknown prospective diagnostic and tracking performance in multicenter settings.

Objectives: The aim was to investigate the diagnostic accuracy of NM-MRI in early PD in a multiprotocol setting and to determine and compare serial NM-MRI changes in PD and controls.

Imaging Cognitive Impairment and Impulse Control Disorders in Parkinson's Disease.

Dementia and mild forms of cognitive impairment as well as neuropsychiatric symptoms (i. e., impulse control disorders) are frequent and disabling non-motor symptoms of Parkinson's disease (PD).

Dissociable effects of age and Parkinson's disease on instruction-based learning.

The cognitive deficits associated with Parkinson's disease vary across individuals and change across time, with implications for prognosis and treatment. Key outstanding challenges are to define the distinct behavioural characteristics of this disorder and develop diagnostic paradigms that can assess these sensitively in individuals. In a previous study, we measured different aspects of attentional control in Parkinson's disease using an established fMRI switching paradigm.

Longitudinal changes in movement-related functional MRI activity in Parkinson's disease patients.

Introduction: Functional brain imaging has shown alterations in the basal ganglia, cortex and cerebellum in Parkinson's disease patients. However, few functional imaging studies have tested how these changes evolve over time. Our study aimed to test the longitudinal progression of movement-related functional activity in Parkinson's disease patients.

Is Chelation Therapy a Potential Treatment for Parkinson's Disease?

Iron loading in some brain regions occurs in Parkinson's Disease (PD), and it has been considered that its removal by iron chelators could be an appropriate therapeutic approach. Since neuroinflammation with microgliosis is also a common feature of PD, it is possible that iron is sequestered within cells as a result of the "anaemia of chronic disease" and remains unavailable to the chelator. In this review, the extent of neuroinflammation in PD is discussed together with the role played by glia cells, specifically microglia and astrocytes, in controlling iron metabolism during inflammation, together with the results of MRI studies.

Iron and inflammation: in vivo and post-mortem studies in Parkinson's disease.

In these present studies, in vivo and and post-mortem studies have investigated the association between iron and inflammation. Early-stage Parkinson's disease (PD) patients, of less than 5 years disease duration, showed associations of plasmatic ferritin concentrations with both proinflammatory cytokine interleukin-6 and hepcidin, a regulator of iron metabolism as well as clinical measures. In addition ratios of plasmatic ferritin and iron accumulation in deep grey matter nuclei assessed with relaxometry T2* inversely correlated with disease severity and duration of PD.

Longitudinal functional connectivity changes related to dopaminergic decline in Parkinson's disease.

Background: Resting-state functional magnetic resonance imaging (fMRI) studies have demonstrated that basal ganglia functional connectivity is altered in Parkinson's disease (PD) as compared to healthy controls. However, such functional connectivity alterations have not been related to the dopaminergic deficits that occurs in PD over time.

Objectives: To examine whether functional connectivity impairments are correlated with dopaminergic deficits across basal ganglia subdivisions in patients with PD both cross-sectionally and longitudinally.

Parkinson's disease laterality: a C-PE2I PET imaging study.

Asymmetry of striatal dopaminergic deficits and motor symptoms is a typical characteristic of idiopathic Parkinson's disease (PD). This study aims to characterise the trend of asymmetry in moderate-stage PD. We performed a 19-month longitudinal study in 27 patients with PET-CT imaging and appropriate clinical assessments.

Nigrostriatal dopamine transporter availability, and its metabolic and clinical correlates in Parkinson's disease patients with impulse control disorders.

Purpose: Previous studies in patients with Parkinson's disease (PD) and impulse control disorders (ICDs) have produced heterogeneous results regarding striatal dopamine transporter (DaT) binding and activity in the mesocorticolimbic network. Our aim here was to study the relationship between striatal DaT availability and cortical metabolism, as well as motor, behavioural and cognitive features of PD patients with ICD.

Methods: In a group of PD patients with ICD (PD-ICD, n = 16) and 16 matched PD patients without ICD (PD-noICD, n = 16), DaT single-photon emission computed tomography (SPECT) imaging (DaTSCAN) was used to study DaT availability in predefined striatal volumes of interest (VOIs): putamen, caudate nucleus and ventral striatum (VS).

Relationship between neuromelanin and dopamine terminals within the Parkinson's nigrostriatal system.

Parkinson's disease is characterized by the progressive loss of pigmented dopaminergic neurons in the substantia nigra and associated striatal deafferentation. Neuromelanin content is thought to reflect the loss of pigmented neurons, but available data characterizing its relationship with striatal dopaminergic integrity are not comprehensive or consistent, and predominantly involve heterogeneous samples. In this cross-sectional study, we used neuromelanin-sensitive MRI and the highly specific dopamine transporter PET radioligand, 11C-PE2I, to assess the association between neuromelanin-containing cell levels in the substantia nigra pars compacta and nigrostriatal terminal density in vivo, in 30 patients with bilateral Parkinson's disease.

Protocol of a single group prospective observational study on the diagnostic value of 3T susceptibility weighted MRI of nigrosome-1 in patients with parkinsonian symptoms: the N3PD study (nigrosomal ron maging n Parkinson's disease).

Introduction: Parkinson's disease (PD) is the most common movement disorder in the elderly and is characterised clinically by bradykinesia, tremor and rigidity. Diagnosing Parkinson's can be difficult especially in the early stages. High-resolution nigrosome MRI offers promising diagnostic accuracy of patients with established clinical symptoms; however, it is unclear whether this may help to establish the diagnosis in the early stages of PD, when there is diagnostic uncertainty.

Patterns of grey matter loss associated with motor subscores in early Parkinson's disease.

Classical motor symptoms of Parkinson's disease (PD) such as tremor, rigidity, bradykinesia, and axial symptoms are graded in the Movement Disorders Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) III. It is yet to be ascertained whether parkinsonian motor symptoms are associated with different anatomical patterns of neurodegeneration as reflected by brain grey matter (GM) alteration. This study aimed to investigate associations between motor subscores and brain GM at voxel level.

C-PE2I and F-Dopa PET for assessing progression rate in Parkinson's: A longitudinal study.

Background: F-dopa PET measuring aromatic l-amino acid decarboxylase activity is regarded as the gold standard for evaluating dopaminergic function in Parkinson's disease. Radioligands for dopamine transporters are also used in clinical trials and for confirming PD diagnosis. Currently, it is not clear which imaging marker is more reliable for assessing clinical severity and rate of progression.

Iron metabolism and its detection through MRI in parkinsonian disorders: a systematic review.

Iron deposition in the brain normally increase with age, but its accumulation in certain regions is observed in a number of neurodegenerative diseases including Parkinson's disease (PD) and other parkinsonisms. Whether iron overload leads to dopaminergic neuronal death in the SN of PD patients or is instead simply a by-product of the neurodegenerative progression is still yet to be ascertained. Magnetic resonance imaging (MRI) is a non-invasive method to assess brain iron content in PD patients.

Brain iron chelation by deferiprone in a phase 2 randomised double-blinded placebo controlled clinical trial in Parkinson's disease.

Parkinson's disease (PD) is associated with increased iron levels in the substantia nigra (SNc). This study evaluated whether the iron chelator, deferiprone, is well tolerated, able to chelate iron from various brain regions and improve PD symptomology. In a randomised double-blind, placebo controlled trial, 22 early onset PD patients, were administered deferiprone, 10 or 15 mg/kg BID or placebo, for 6 months.

Neuromelanin in parkinsonian disorders: an update.

Neuromelanin (NM) is a dark pigment that accumulates linearly with aging in substantia nigra (SN) and locus coeruleus (LC). The dual protective and toxic role of NM has been hypothesized according to its intraneuronal or extraneuronal deposition. The melanized dopaminergic neurons in SN and LC seem to have special vulnerability to neurodegeneration in Parkinson's disease (PD).

Motor associations of iron accumulation in deep grey matter nuclei in Parkinson's disease: a cross-sectional study of iron-related magnetic resonance imaging susceptibility.

Background And Purpose: To determine whether iron deposition in deep brain nuclei assessed using high-pass filtered phase imaging plays a role in motor disease severity in Parkinson's disease (PD).

Methods: Seventy patients with mild to moderate PD and 20 age- and gender-matched healthy volunteers (HVs) underwent susceptibility-weighted imaging on a 3 T magnetic resonance imaging scanner. Phase shifts (radians) in deep brain nuclei were derived from high-pass filtered phase images and compared between groups.

MM2 subtype of sporadic Creutzfeldt-Jakob disease may underlie the clinical presentation of progressive supranuclear palsy.

The classical presentation of sporadic Creutzfeldt-Jakob disease (sCJD) is rapid progressive dementia often associated with myoclonus and ataxia followed by death in less than a year from diagnosis. The few patients in the literature who presented with parkinsonism and who were suspected to have progressive supranuclear palsy (PSP) all ran a malignant course and most of them died within 3 years of diagnosis. We screened the Queen Square Brain Bank database and, among 213 patients with a clinical diagnosis of PSP, we found ten patients with 3 years or less disease duration, including one patient with CJD pathology.