Neuroimaging acquisition

A conventional head MRI at 3.0‐T (Sigma, GE Medical Systems, Milwaukee, WI, USA) was performed on 141 PD patients who were currently on medication. FLAIR images were used to grade WMH. FLAIR sequence images were acquired with the following parameters:turbo spin echo, repeat time (TR) = 8000 ms, echo time (TE) = 340 ms, T1 = 2400 ms, matrix = 256×256, slice thickness = 1 mm, 170 slices, and voxel size = 1.0 × 1.0 × 1.0 mm³. Head MRI scans were evaluated by two experienced neurologists who were blind to the clinical status of each patient. The Fazekas visual semiquantitative rating scale was used to easily assess the severity and location of WMH. The locations of WMH were divided into two different types: periventricular hyperintensities (PVH) and deep white matter hyperintensities (DWMH). PVH were graded as 0 = absence, 1 = “caps” or pencil‐thin lining, 2 = smooth “halo,” or 3 = irregular PVH extending into the deep white matter. DWMH were rated as 0 = absence, 1 = punctate foci, 2 = beginning confluence of foci, or 3 = large confluent areas ^[6].The Fazekas WMH score was the total of the deep and periventricular WMH scores (Figure 2).

Representative T2‐FLAIR images of WMH A: PVH grade 1 and DWMH grade 1; B: PVH grade 2 and DWMH grade 2; C: PVH grade 3 and DWMH grade 3. Abbreviations: WMH, white matter hyperintensities; PVH, periventricular hyperintensities; DWMH, deep subcortical white matter hyperintensities.