We designed SWAN-based algorithm for assessment the pattern of ferromagnetic substances spatial distribution in brain tissue in patients with Parkinson disease. We achieved high diagnostic accuracy in identification of microhemorrhagic changes. In 27 of the 43 patients with PD were observed hemorrhagic lesions in the chronic phase. In the control group, such changes were not observed. In addition, patients with PD had specific localization of lesions (in the epiphysis and vascular plexus).
We designed SWAN-based algorithm for assessment the pattern of ferromagnetic substances spatial distribution in brain tissue in patients with Parkinson disease. We achieved high diagnostic accuracy in identification of microhemorrhagic changes. In 27 of the 43 patients with PD were observed hemorrhagic lesions in the chronic phase. In the control group, such changes were not observed. In addition, patients with PD had specific localization of lesions (in the epiphysis and vascular plexus).
Parkinson’s disease (PD) is among the most prevalent neurodegenerative conditions. Despite decades of investigations, its cause remains unknown and the molecular pathways of neurodegeneration remain poorly understood [1]. The prevalence of Parkinson Disease in industrialised countries is generally estimated at 0.3% of the entire population and about 1% in people over 60 years of age [2]. At the moment, there is no non-invasive procedure for early diagnosis of BP. The development of quantitative MRI has made them useful for the diagnosis of Parkinson Disease [3, 4]. Quantitative Mapping of Magnetic Susceptibility (SWAN) is a non-invasive MRI protocol that measures the spatial distribution of magnetic sensitivity in tissue. This method is highly sensitive to the level of iron in tissues, including posthemorrhagic foci [5].
Purpose of the study.
Objective: to study the diagnostic capabilities of SWAN technology in evaluating pathological processes and microfocal lesions of the central nervous system, in patients with Parkinson's disease.
Materials and methods.
SWAN technology was implemented on a high-field MR-scanner (General Electric Discovery MR750W, 3.0 T). The study was performed in 43 patients with Parkinson's disease of the State Scientific-Research Institute of Physiology and Basic Medicine clinic. The control group (without PD) included 100 healthy volunteers. An analysis of the foci of anomalous accumulation of iron-containing elements (as a consequence of microhemorrhages) in the morphometric plan (linear dimensions), with the evaluation of the form factor was done.
Results.
The usage of SWAN technology combined with structural MRI allowed to achieve improved accuracy of diagnosis of micro-hemorrhagic changes in patients with PD and verify the pathological mechanisms of micro-hemorrhages (presence micro-varicose or micro-hemangiomatous changes in cerebral vessels, the presence of asymmetry in cerebral blood flow and / or blood outflow, the presence of manifestations of increased venous and / or intracranial pressure, a combination of micro -hemorrhagic and ischemic manifestations). In 27 (62.7%) 43 (100%) patients with PD posthemorrhagic foci were observed in the chronic phase, in the basal ganglia, in 9 (20.9%) in the right basal ganglia and in 18 (41.8%) in left basal nuclei, as well as foci in the epiphysis 5 (11.6%) and in the vascular plexus 4 (9.3%). At the same time the localization of foci in the pituitary and in the vascular plexuses was definitive for patients with PD. In the control group, such changes were not observed.
The conclusion.
Thus, the measurement of the intensity of microhemorrhagic changes with the use of SWAN in patients with PD showed a high frequency of foci of abnormal accumulation of iron-containing elements. Accordingly, SWAN can be used as an additional method for early diagnosis of BP, highly sensitive to the accumulation of iron-containing components in the brain tissues.
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