RESUMO
Abstract Introduction: Triphasic waves (TW) constitute an electroencephalographic pattern associated with certain kinds of encephalopathy. Brain atrophy may be a predisposing factor linked with TW. Objective: To compare the degree of brain atrophy and white matter disease between patients with acute encephalopathy with and without TW. Methods: A retrospective observational study including adult patients with encephalopathy, with and without TW, hospitalized between 2016 and 2017. The degree of brain atrophy and white matter lesion were defined using the Global Cortical Atrophy and Age Related White Matter Changes (ARWMC) scales, respectively. Scores were compared between groups. Mortality rates were registered. Results: Sixteen patients with TW were identified matched by age and sex with 30 patients without TW. The mean age was 80 years in the TW group. Women represented 87.5%. Multifactorial encephalopathy was the most frequent diagnosis followed by metabolic encephalopathy. Patients with TW had more brain atrophy (10.43 vs 6.9, p= 0.03). Mean ARWMC was 9.43±6.5 and 8.5 ±7.89 in patients with and without TW respectively (p= 0.5). Mortality rate was higher in the TW group (31.25 vs 6.66% p= 0.02). Conclusions: Patients with acute encephalopathy and TW had higher degree of cerebral atrophy. It is possible that this structural alteration predisposes to the appearance of TW. There was no significant difference in white matter lesion degree. The mortality of the TW group was high, so future studies are necessary to determine their prognostic value.
Resumen Introducción: Las ondas trifásicas (OT) constituyen un patrón electroencefalográfico asociado con diversas encefalopatías. La atrofia cerebral podría predisponer a su aparición. Objetivo: Comparar el grado de atrofia cerebral y de lesión de sustancia blanca en pacientes con encefalopatía aguda con y sin OT. Métodos: Estudio observacional retrospectivo, incluyó pacientes adultos con encefalopatía aguda con y sin OT internados entre 2016 y 2019. El grado de atrofia cerebral y de lesión de sustancia blanca se definieron según las escalas Global Cortical Atrophy y Age Related White Matter Changes (ARWMC), respectivamente. Se compararon los puntajes entre grupos. Se registró la mortalidad. Resultados: Se identificaron 16 pacientes con OT y 30 sin OT pareados según edad y sexo. La edad promedio del grupo con OT fue 80 años. El 87.5% fueron mujeres. La encefalopatía multifactorial fue el diagnóstico más frecuente seguido de la encefalopatía metabólica. El grado de atrofia fue mayor en pacientes con OT (10.43 vs 6.9, p= 0.03). El puntaje ARWMC fue 9.43 ±6.5 y 8.5 ±7.89 en pacientes con y sin OT respectivamente (p= 0.5). La mortalidad fue mayor en el grupo con OT (31.25 vs 6.66% p= 0.02). Conclusiones: Pacientes con encefalopatía aguda y OT tuvieron mayor grado de atrofia cerebral. Dicha alteración estructural podría relacionarse con la aparición de OT. No hubo diferencias significativas en el grado de lesión de sustancia blanca. La mortalidad del grupo con OT fue elevada. Son necesarios estudios para determinar su valor pronóstico.
RESUMO
Periodic electroencephalographic (EEG) patterns consist of discharges usually epileptiform in appearance, which occur at regular intervals, in critical patients. They are commonly classified as periodic lateralized epileptiform discharges (PLEDs), bilateral independent PLEDs or BIPLEDs, generalized epileptiform discharges (GPEDs) and triphasic waves. Stimulus-induced rhythmic, periodic or ictal discharges (SIRPIDs) are peculiar EEG patterns, which may be present as periodic discharges. The aim of this study is to make a review of the periodic EEG patterns, emphasizing the importance of their recognition and clinical significance. The clinical significance of the periodic EEG patterns is uncertain, it is related to a variety of etiologies, and many authors suggest that these patterns are unequivocally epileptogenic in some cases. Their recognition and classification are important to establish an accurate correlation between clinical, neurological, laboratorial and neuroimaging data with the EEG results.
Padrões eletrencefalográficos (EEG) periódicos consistem em descargas geralmente epileptiformes em aparência, que ocorrem a intervalos regulares, em pacientes críticos. Esses padrões são habitualmente classificados como descargas epileptiformes periódicas lateralizadas (PLEDs), PLEDs bilaterais e independentes ou BIPLEDs, descargas epileptiformes periódicas generalizadas (GPEDs) e ondas trifásicas. Descargas rítmicas, periódicas ou ictais induzidas por estímulos (SIRPIDs) são padrões eletrencefalográficos peculiares, que podem se apresentar como descargas periódicas. O objetivo deste estudo é fazer uma revisão dos padrões EEG periódicos, enfatizando a importância do seu reconhecimento e seu significado clínico. O significado clínico dos padrões EEG periódicos é incerto. Está relacionado a uma variedade de etiologias e muitos autores sugerem que tais padrões sejam inequivocamente de natureza epileptogênica em alguns casos. O seu reconhecimento e classificação são importantes para estabelecer uma correlação acurada entre dados clínicos, neurológicos, laboratoriais e de neuroimagem com os resultados de EEG.