The Assessment of Basic Features of Electroencephalography in Metabolic Encephalopathies
Abstract
Background: The comparison of the electroencephalography (EEG) data with the patients’ primary diagnosis and the relationship with the prognosis was assessed with this study in the cases that are being followed up with the diagnosis of metabolic encephalopathy (ME).
Methods: A total of 306 patients who were being followed up due to ME between January 2009 and September 2011 were included in the study. The etiologic causes in the cases were detected as hyponatremia in 26.2%, hypoxic ischemic encephalopathy in 23.8%, renal failure in 14.4%, hepatic failure in 11.7%, diabetes mellitus in 8.2%, endocrinopathies except for diabetes mellitus in 8.8%, and hypernatremia in the remaining 6.9%. EEG examinations were performed with two different methods. Firstly, 269 of 367 EEGs were analyzed for baseline activity, divided in six stages.
Results: Another assessment in EEG examination considering abnormal patterns was performed and 281 of 367 EEGs were taken into this assessment; reduction in the alpha, asynchronous slow waves, focal slow activities, triphasic waves, burst-suppression pattern, and generalized or focal spike-sharp activities were observed. There were no differences between the EEG groups statistically by age and sex. There were no statistical associations between diagnoses and the change of consciousness (P = 0.187). There was no significant correlation between EEG findings and diagnostic groups (P = 0.126); however, it was statistically shown that as the impaired consciousness increased, the EEG stages moved forward to worse stages (P < 0.001).
Conclusion: We think that EEG examination does not contribute to the diagnosis of the etiology of the disease; however, it may be useful in follow-ups and prognosis in ME.
J Neurol Res. 2014;4(4):101-109
doi: http://dx.doi.org/10.14740/jnr285w