A utilização da eletroencefalografia quantitativa como ferramenta de diagnóstico e de pesquisa clínica em pacientes ambulatoriais e em estado de coma

Abstract

The objective of the present study was to evaluate the usefulness of quantitative electroencephalography (EEGq) tracing in different study models. Five different study models were performed with the use of EEGq. The first and second models evaluated the ability of the method to be used with an adjuvant tool in the differential diagnosis of co morbidities in children and teenager with school difficulties. In the second and third models, the ability of the method to assess the presence of aggressive symptoms in children with ADHD (model 3) and as a tool for discernment of mild cognitive impairment in children with low school performance due to mild cognitive impairment. In the fifth model the usefulness of the method in the evolutionary follow-up of patients in coma was evaluated. The results: For model one: it was observed that children with school difficulties with marked difficulties in reading, writing and calculus presented to EEG lower mean frequencies in the center-parietal-temporal regions when compared with children with learning disabilities who did not present this symptom, Children with learning disabilities with behavioral disorders present EEGq with higher average frequencies in the frontal regions when compared to children with school difficulties without behavioral disorder. For model two: children with severe reading, writing and calculus disorders, especially younger ones, had lower mean frequencies in most regions of the scalp when compared to patients with school difficulties who did not have such difficulties. The same is observed in young children with speech impairments. Patients with behavioral problems have higher mean frequencies in the frontal regions, when compared to children with school difficulties without behavior problems. Children with clear signs of cognitive impairment have lower average frequencies in posterior regions, compared to patients with school difficulties without symptoms of cognitive deficits, patients with severe attention deficit have lower average frequencies in the left temporal region. For model 3: dysfunctional anger in children with ADHD leads to increased EEG frequencies and low variance when compared to EEG frequencies associated with children with ADHD without dysfunctional anger. For model 4: Signal processing by the mean frequency calculation allowed to observe differences between the EEGs of children with school difficulties with and without mild cognitive impairment, and children with school difficulties who have mild cognitive deficits presented lower frequencies in their EEGs. For model 5: The rhythms that stood out most positively in the distinction of the state of consciousness were Alpha and Delta, thus enhancing a type of quantifier of distinction. Regarding the topographic analysis of the cortex, the frontal electrodes were generally more efficient in terms of state differentiation, followed by the electrodes of the central region. In this sense, from the point of view of coherence, the pairs of electrodes FP1-FP2, F3-F4 and O1-O2 allow a better differentiation of the coma state with respect to neurological normality.