Early Alterations in De Novo Parkinson's Disease Revealed by Diffusion Tensor Imaging: Preliminary Study

Abstract

Background/Objectives: Parkinson's disease (PD) is characterized by progressive neurodegeneration affecting both motor and non-motor functions. Identifying early alterations in PD patients before the onset of dopaminergic therapy is crucial for understanding disease progression and developing targeted interventions. This study aimed to investigate early changes in the putamen and thalamus in de novo PD patients using diffusion tensor imaging (DTI) compared to healthy controls. Methods: Thirty-one de novo PD patients and thirty-three healthy controls underwent DTI scanning. Tract-based spatial statistics were used to compare fractional anisotropy (FA) values between groups. Results: De novo PD patients exhibited significantly lower FA values in the right thalamus compared to controls, suggesting alterations in neuronal integrity or fiber degeneration in the early stages of the disease. However, no significant differences were demonstrated for FA values in the putamen between groups. Conclusions: We demonstrated that the FA value in the right thalamus was lower in PD compared with healthy controls. These findings highlight the potential of DTI as a non-invasive tool for detecting early neural changes in PD patients. Further studies would be helpful to assess the clinical utility of serial FA measurements of the subcortical gray matter in objective quantification of disease progression and monitoring of the therapeutic response.

Keywords: Parkinson’s disease; de novo Parkinson’s disease; diffusion tensor imaging; fractional anisotropy; thalamus and putamen.

Figure 1

Interface of the MR Diffusivity tool of the IntelliSpace V 9.0 software used for the analysis of diffusion images. By selecting the values of b = 0 s/mm² and b = 1000 s/mm², the FA maps co-registered to the diffusion-weighted images were generated. Freehand ROIs were drawn on the putamen and elliptical ROIs on the thalami on the b = 0 s/mm² images. For each ROI, the FA values obtained were maximum, minimum, mean and standard deviation. Unit of measurement area mm².

Figure 2

Box-and-whisker plots of FA values in the right and left thalamus between de novo PD patients (PDdn) and healthy controls (C).