Clinical StudyStriatal silent lacunar infarction is associated with changes to the substantia nigra in patients with early-stage Parkinson's disease: A diffusion kurtosis imaging study

- Nearly 50% Parkinson's disease (PD) patients older than 50 suffered from striatal silent lacunar infarction (SSLI).
- SSLI is associated with changes to the substantia nigra (SN) in PD patients.
- Structural changes to the SN could be detected by diffusion kurtosis imaging.
- Structural changes to the SN become more obvious with an increase in SSLI lesions.
- It was implied that SSLI might aggravate the motor disorder of patients with PD.

A recent study has shown that striatal silent infarction may occur secondary to the degeneration of dopaminergic neurons in the substantia nigra (SN) of mice. However, it is uncertain whether this phenomenon occurs in patients with early-stage Parkinson's disease (PD) and can be detected by diffusion kurtosis imaging (DKI). A total of 72 untreated patients with early-stage PD underwent conventional MRI and DKI. Participants were divided into control and striatal silent lacunar infarction (SSLI) groups. The differences in mean kurtosis (MK) values of the SN, Hoehn-Yahr (H-Y) staging, and Unified Parkinson's Disease Rating Scale (UPDRS) III score between groups, were analyzed. Linear regression analysis was used to correlate age, SSLI count, silent lacunar infarction count in other brain areas and age-related white matter change score with MK values of the SN. Spearman correlation coefficient analysis was used to correlate MK values of the SN and SSLI count with H-Y staging and UPDRS III score. There was no significant difference in the severity of disease between two groups; however, MK values of the SN with SSLI present were significantly higher than in SN without SSLI. In addition, SSLI count had linear correlation with MK values of the SN, which had positive correlation with H-Y-staging and UPDRS III score. SSLI is associated with structural changes to the SN in patients with early-stage PD, detectable by DKI, and may aggravate their motor impairments.