Brain Volumetry Markers and Cognitive Status in Relapsing-Remitting Multiple Sclerosis /// Мозъчни волуметрични показатели и когнитивен статус при пристъпно-ремитентна множествена склероза

Abstract

Изследването на клиничните прояви на невродегенеративния процес при множествена склероза от различни аспекти може да допринесе за неговото по-задълбочено изучаване и за идентифициране на нови рискови фактори и потенциални маркери, предсказващи хода на заболяването или отделни негови характеристики. Проведено е срезово проучване на волуметрични показатели и когнитивен статус, изследван чрез невропсихологични тестове и събитийно-свързани потенциали, при пациенти с пристъпно-ремитентна множествена склероза. Изследвани са 138 лица: пациенти с пристъпно-ремитентна множествена склероза и контролна група. Всички са отговорили на съставен за целта въпросник и са провели невропсихологично изследване. При част от контингента са извършени волуметрична обработка и анализ на МРТ, изследвани са ССП (Р300). Морфометричните изследвания са извършени чрез високоспециализирани, достъпни, със свободен лиценз софтуерни продукти. Установените показатели на събитийно-свързания потенциал Р300 показват своеобразна картина на значими отклонения при пациентите. Доказва се статистически значимо наличие на когнитивни нарушения и отклонения във волуметричните, електрофизиологичните и някои функционални показатели при пациентите. Получена е нова информация за корелации и причинно-следствени отношения между показателите от изследваните основни групи, в потвърждение на общоприетите концепции за видовете патологични прояви и влиянието им върху оценяваните чрез приложения подход параметри. Утвърдена е цялостна концепция за комплексно изследване на мозъчни волуметрични показатели и когнитивен статус – с невропсихологични тестове и СПП – при пристъпно-ремитентна множествена склероза.

Quantitative assessment of brain atrophy in MS is also used for objective assessment of cognitive disorders that have been studied more and more extensively. In MS, they have a different profile than the one described in neurodegenerative diseases presenting with dementia. This requires the use of specifically designed and tailored neuropsychological instruments, tests and batteries. Additional objective evidence of cognitive dysfunction and neurodegeneration can be searched for by examining event-related potentials (ERP). The method is not routinely used but may show promise in research, especially in combination with other techniques. The study of clinical manifestations of the neurodegenerative process in MS from different aspects - neuroimaging, neuropsychological and electrophysiological, can contribute to its in-depth study and to the identification of new risk factors and potential markers predicting the course of the disease or its individual characteristics. Some quantitative markers have already been applied in studies of novel therapeutic agents and strategies. It has been assumed that measuring the volume of brain structures using appropriate software tools on MRI images would show statistically significant differences between patients with RRMS and a control group, values of patients presumed to be lower. The study of cognitive functions of patients with RRMS and a control group by a dedicated neuropsychological battery would show statistically significant differences. Patients are expected to achieve lower results. ERP study in patients with RRMS would show significantly weaker results of parameters such as latency, amplitude response time and number of wrong presses of the patient button, compared to a control group. There are significant correlations and causal relationships between neuropsychological, volumetric, electrophysiological and functional parameters derived from a study of patients with RRMS. The purpose of this thesis is to conduct cross-sectional study of volumetric performance and cognitive status evaluated by neuropsychological tests and event-related potentials in patients with relapsing-remitting multiple sclerosis, to identify correlations and causal relationships between key indicators and to establish the methods with potential practical importance. 138 individuals were examined: RRMS patients and a control group. Volumetric assessment shows a significantly smaller volume of white matter and subcortical structures in RRMS patients compared to healthy subjects. Neuropsychological assessment demonstrates cognitive impairment in patients with RRMS, affecting information processing speed, visuospatial functions, executive functions, and memory. Patients with RRMS show prolonged latency of P300 compared to healthy subjects. Complex assessment of patients with RRMS using brain volumetry, neuropsychological and functional tests, and ERP, shows impairment in each of the spheres, and provides information on the condition of the patient and on the development of the disease. In patients with RRMS there are correlations and consequential relationships between volumetric, neuropsychological, electrophysiological, and functional parameters. Brain atrophy leads to slower processing of information, to higher degree of disability, to lower amplitude of P300, and to longer time for T25FWT.