White matter changes in drug-naïve Parkinson's disease patients with impulse control & probable REM sleep behavior disorders.

Background: According to epidemiological studies, Parkinson's disease (PD) patients with probable REM sleep behavior disorder (pRBD) are more prone to develop impulse control disorders (ICDs), which is shown to be present in drug-naïve PD patients, and vice versa.

Objectives: To investigate white-matter integrity differences, with and without comorbid pRBD and ICDs.

Methods: 149 de-novo PD patients and 30 age- and gender-matched controls from the Parkinson's Progression Markers Initiative were studied.

Impact of Ga-PSMA-11 PET on the Management of Recurrent Prostate Cancer in a Prospective Single-Arm Clinical Trial.

Prostate-specific membrane antigen (PSMA) ligand PET induces management changes in patients with prostate cancer. We aim to better characterize the impact of Ga-PSMA-11 PET (Ga-PSMA PET) on management of recurrent prostate cancer in a large prospective cohort. We report management changes after Ga-PSMA PET, a secondary endpoint of a prospective multicenter trial in men with biochemical recurrence of prostate cancer.

Multiple modality biomarker prediction of cognitive impairment in prospectively followed de novo Parkinson disease.

Objectives: To assess the neurobiological substrate of initial cognitive decline in Parkinson's disease (PD) to inform patient management, clinical trial design, and development of treatments.

Methods: We longitudinally assessed, up to 3 years, 423 newly diagnosed patients with idiopathic PD, untreated at baseline, from 33 international movement disorder centers. Study outcomes were four determinations of cognitive impairment or decline, and biomarker predictors were baseline dopamine transporter (DAT) single photon emission computed tomography (SPECT) scan, structural magnetic resonance imaging (MRI; volume and thickness), diffusion tensor imaging (mean diffusivity and fractional anisotropy), cerebrospinal fluid (CSF; amyloid beta [Aβ], tau and alpha synuclein), and 11 single nucleotide polymorphisms (SNPs) previously associated with PD cognition.

Progression of Regional Microstructural Degeneration in Parkinson's Disease: A Multicenter Diffusion Tensor Imaging Study.

This study aimed to identify the utility of diffusion tensor imaging (DTI) in measuring the regional distribution of abnormal microstructural progression in patients with Parkinson's disease who were enrolled in the Parkinson's progression marker initiative (PPMI). One hundred and twenty two de-novo PD patients (age = 60.5±9) and 50 healthy controls (age = 60.

Diffusion imaging of nigral alterations in early Parkinson's disease with dopaminergic deficits.

Background: This study reports the baseline characteristics of diffusion tensor imaging data in Parkinson's disease (PD) patients and healthy control subjects from the Parkinson's Progression Markers Initiative. The main goals were to replicate previous findings of abnormal diffusion imaging values from the substantia nigra. in a large multicenter cohort and determine whether nigral diffusion alterations are associated with dopamine deficits.

Diffusion tensor imaging of the nigrostriatal fibers in Parkinson's disease.

Background: Parkinson's disease (PD) is histopathologically characterized by the loss of dopamine neurons in the substantia nigra pars compacta. The depletion of these neurons is thought to reduce the dopaminergic function of the nigrostriatal pathway, as well as the neural fibers that link the substantia nigra to the striatum (putamen and caudate), causing a dysregulation in striatal activity that ultimately leads to lack of movement control. Based on diffusion tensor imaging, visualizing this pathway and measuring alterations of the fiber integrity remain challenging.