Combined quantitative analysis of the nigro-striata system in multiple system atrophy and Parkinson's disease.

Degeneration of the nigrostriatal system occurs in multiple system atrophy (MSA) and Parkinson's disease (PD) via distinct pathological mechanisms. Here, we investigated nigrostriatal degeneration in MSA and PD by combining a newly developed method for evaluating the regional accumulation of dopamine transporter single-photon emission computed tomography (DAT SPECT) and individual voxel-based morphometry adjusting covariates (iVAC). We recruited 17 MSA patients and 13 PD patients, and compared their clinical and imaging indices.

Decreased heart rate variability in sympathetic dominant states in Parkinson's disease and isolated REM sleep behavior disorder.

Introduction: Parkinson's disease (PD) presents with decreased heart rate variability (HRV) from its early stages. However, most of its evidence originates from HRV measurements in parasympathetic dominant states. In this study, we aimed to examine whether HRV in sympathetic dominant states during the head-up tilt table test (HUT) serves as a marker of autonomic dysfunction in PD and isolated REM sleep behavior disorder (iRBD).