Parkinson’s disease patterns in neurodegeneration with brain iron accumulation
Aim: to evaluate the association of iron deposition in the structures of the extrapyramidal system with the clinical picture patterns in patients with various stages of Parkinson’s disease (PD). Patients and Methods: the study included 92 patients with PD (42 patients with stage II according to the Hoehn and Yahr scale, and 50 patients with stage III according to the Hoehn and Yahr scale). All patients underwent comprehensive clinical and neuropsychological testing according to the following scales: Unified Parkinson’s Disease Rating Scale (UPDRS), Freezing of Gait Questionnaire (FOGQ), Gait and Balance Scale (GABS), Frontal Assessment Battery (FAB), Mini-Mental State Examination (MMSE), Beck’s Depression Inventory. Also, all patients underwent magnetic resonance imaging (MRI) of the head using the Magnetom Trio A Tim 3.0 Tesla magnetic resonance tomograph with a susceptibility weighted imaging (SWI). ROI: substantia nigra (SN), nucleus ruber (NR), putamen, pale globe (PG), head of the caudate nucleus (CN), dentate body (DB). During SWI, the signal strength from each studied area was manually measured. Results: statistically significant differences were found in the UPDRS and its sections, FOGQ, GABS, MMSE and FAB, between patients with stage II and III PD according to the Hoehn and Yahr scale. Statistically significant differences in signal strength indicators from the right and left SNs, right and left putamens, left PG, right and left CNs were revealed among the studied groups. Correlation analysis results showed that iron deposition in the structures of the extrapyramidal system with the UPDRS and its sections results predominated in patients with stage II according to the Hoehn and Yahr scale; in patients with stage III - with the UPDRS III, FOGQ, GABS, MMSE, FAB and Beck’s Depression Inventory. Conclusion: a gradual increase in the brain iron accumulation in the PD progression was revealed. Multiple associations of iron deposition in the structures of the extrapyramidal system with various patterns of the clinical picture were revealed in patients with both stages II and III according to the Hoehn and Yahr scale. The combined use of complex clinical and neuropsychological examination with MRI of the head in SWI mode allows to assess the role of iron in the PD pathogenesis, identify biomarkers of disease progression and the development of its motor and non-motor manifestations.