Transcranial sonography in patients with Parkinson's disease with glucocerebrosidase mutations

The aim of this study was to search for possible differences in the findings of transcranial sonography (TCS) between groups of patients with glucocerebrosidase (GBA)-associated Parkinson's disease (PD) (4 patients with Gaucher disease type 1 and parkinsonism [GD+PD+] and 18 PD patients with heterozygous GBA mutations; [GBA+PD+]) and groups of 12 patients with Gaucher disease type 1 and no signs of parkinsonism (GD+PD-), 9 asymptomatic carriers of heterozygous GBA mutations (GBA+PD-), 32 sporadic PD patients (sPD), and 43 healthy controls.

In all groups of patients, except asymptomatic carriers of heterozygous GBA mutations (mean ± SD: 0.16 ± 0.03 cm(2)), the maximal areas of substantia nigra hyperechogenicity (aSN-max) was higher (GD+PD+: 0.28 ± 0.15 cm(2); GD+PD-: 0.18 ± 0.06 cm(2); GBA+PD+: 0.27 ± 0.06 cm(2); sPD: 0.28 ± 0.10 cm(2)) when compared to controls (0.12 ± 0.08 cm(2)) (p = 0.001). In GBA-associated PD (GD+PD+ and GBA+PD+) and sPD, aSNmax values were very similar. Moderate or marked SN hyperechogenicity was present in 87.5% of sPD patients and in 83% of PD patients with heterozygous GBA mutations, but in only 11.6% of controls, and in 22.2% and 33.3% of patients from GBA+PD- and GD+PD- groups, respectively (p < 0.001). The prevalence of interrupted or missing echogenicity of the brainstem raphe differed between the groups (p = 0.046), while no difference was observed in the diameter of the third ventricle.

TCS findings in GBA-associated PD were consistent to those of patients with sporadic PD.