Cognitive functioning in patients with Chiari malformation type I and relationship with neurological manifestations

Abstract

BACKGROUND. The symptom complex of Chiari malformation type I (CMI) is traditionally characterized by the set of cerebrospinal fluid disorders, coordination disorders, brainstem and myelopathic manifestations. Cognitive impairments, as manifestations of CMI, are little-known area. Study of the characteristics of cognitive status in patients with CMI and analysis of relationship between cognitive phenotype and severity of neurological manifestations can become basis for the formation of a more detailed understanding of this pathology. AIM. The aim was to characterize complex of the neuro-neuropsychological spectrum symptoms and their relationship in patients with CMI. MATERIALS AND METHODS. The main group included 105 adult patients with CMI 74 (70.5%) men and 31 (29.5%) women aged 25.616.89 years. The control group included 50 patients without signs of CMI, other organic brain pathology and cognitive disorders of known etiology 31 (62%) men and 19 (38%) women aged 26.365.00 years. The neuroimaging verification of CMI was performed by magnetic resonance imaging of the brain. Clinical assessment consisted of the collecting complaints, anamnestic information and detailed neurological examination. Comprehensive neuropsychological testing was performed by using MMSE, MoCA and TMT (A and B). RESULTS. Dissociation was noted between prevalence of the typical subjective symptoms and frequency of the objective neurological manifestations in patients with CMI. Among the most frequent subjective symptoms in CMI were headaches and neck pain, asthenia, disorders of the coordination sphere, as well as subjective signs of cognitive dysfunction. Objective neurological deficits were mainly represented by cerebellar disorders. Signs of cognitive dysfunction in the form of memory and attention disorders described by patients with CMI in 20% cases were confirmed by the results of complex neuropsychological testing in comparison with a group of healthy respondents. The relationship of the cognitive deficits with presence and severity of the objective neurological, mainly cerebellar, manifestations in patients with CMI was revealed. CONCLUSIONS. The relationship of cognitive dysfunction with the presence and severity of objective neurological, mainly cerebellar, disorders indicate the complexity of neurological and neuropsychological manifestations in CMI. These data suggest an important role of the disturbed anatomy of the cerebellum and its connections with the cerebral cortex in the pathophysiology of a wide range of major clinical manifestations of CMI.