[Guidelines for recording/analyzing quantitative EEG and evoked potentials. Part II: Clinical aspects]. / Recomendações para o registro/interpretação do mapeamento topográfico do eletrencefalograma e potenciais evocados. Parte II: Correlações clínicas.

Digital EEG (DEEG) and quantitative EEG (QEEG) are recently developed tools present in many clinical situations. Besides showing didactic and research utility, they may also have a clinical role. Although a considerable amount of scientific literature has been published related to QEEG, many controversies still subsist regarding its clinical utilization. Clinical applications are: 1. DEEG is already an established substitute for conventional EEG, representing a clear technical advance. 2. Certain QEEG techniques are an established addition to DEEG for: 2a) screening for epileptic spikes or seizures in long-term recordings; 2b) Operation room and intensive care unit EEG monitoring. 3. Certain QEEG techniques are considered possible useful additions to DEEG: 3a) topographic voltage and dipole analysis in epilepsy evaluations; 3b) frequency analysis in cerebrovascular disease and dementia, mostly when other tests have been inconclusive. 4. QEEG remains investigational for clinical use in postconcussion syndrome, learning disability, attention disorders, schizophrenia, depression, alcoholism and drug abuse. EEG brain mapping and other QEEG techniques should be clinically used only by physicians highly skilled in clinical EEG interpretation and as an adjunct to traditional EEG work.

[Technical recommendations for the electroencephalogram (EEG) recording in suspected brain death]. / Recomendações técnicas para o registro do eletrencefalograma (EEG) na suspeita da morte encefálica.

Brazilian Clinical Neurophysiology Society guidelines and pertaining comments concerning electroencephalogram (EEG) recording in suspected brain death are presented. EEG is not intended as a substitute, rather as a complement to neurologic evaluation.

Recomendaçöes referentes ao registro clínico digital do EEG / Recommendations of Digital Clinical Recording (EEG)

Até recentemente o registro do EEG convencional era feito quase exclusivamente em papel, com a análise sendo executada visualmente. Considerando apenas a gravaçäo (aquisiçä) do EEG, pode-se atualmente dividi-la de forma arbitrária em: 1) sistemas convencionais de registro de EEG em papel; 2) sistemas híbridos com registro em papel e a presença de processadores, porém sem registro digital; os processadores podem permitir, por exemplo, a alteraçäo de programas; 3) sistemas do tipo "paperless" näo digital, com registro através de sistema de modulaçäo em "tape"; 4) sistemas de registro digital do EEG (DEEG). A análise do EEG continua sendo feita da forma visual clássica, porém o registro digital permite também executar diferentes tipos de processamento do sinal do DEEG. Estas recomendaçöes, envolvendo apenas aspectos referentes ao registro clínico digital do EEG, representam o trabalho de uma comissäo organizada pelo departamento de mapeamento topográfico da SBNC e visam näo somente delinear requisitos mínimos como também comentá-los do ponto de vista didático

Midazolam for treatment of refractory neonatal seizures. A case report.

Midazolam is a short-acting water soluble benzodiazepine that has been used with an increasing frequency in the last years. Although there are reports on its use in status epilepticus, there is none in the neonatal period. A pre-term (35 w) AGA newborn infant with a severe hypoxic-ischemic encephalopathy secondary to grade III hyaline membrane disease developed status epilepticus in the first 6 hours of life and was successfully treated with midazolam after phenobarbital and phenytoin failed to achieve seizure control. Dosage schedule was 0.2 mg/kg IV, followed by continuous infusion of 0.025 mg/kg/h. Midazolam is an effective drug for neonatal status epilepticus and more experience should accumulate before it can be routinely employed in the neonatal period. This case shows that it is a possible option before using more dangerous drugs, such as thionembutal.

[Neurophysiological evaluation using multimodal sensory evoked potentials in patients in coma: general aspects]. / Avaliação neurofisiológica por potenciais evocados sensoriais multimodais em pacientes em coma aspectos gerais.

Noninvasive sensory evoked potentials (SEP) performed at bedside in the Intensive Care Unit for patients in coma can be helpful in establishing both a diagnosis and a prognosis. Based on a more than 6-year experience on this subject, the authors discuss general aspects concerning these EP, their probable known generators, and propose a classification depicting different aspects observed for flash visual EP (F-VEP), brainstem auditory EP (BAEP), and median nerve somato-sensory EP (SSEP). Isolated, SSEP shows the best diagnostic and prognostic performance. Nevertheless, the authors consider that multimodality SEP are even better than any isolated EP study; cross-correlating information generated through a horizontal (F-VEP), a vertical (SSEP), and a pathway focusing brainstem in greater detail (BAEP) allows the neurophysiological establishment of the level of lesion in the CNS from a better perspective; besides, SEP can help setting the diagnosis of brain (encephalic) death, and the diagnosis of particular problems concerning each pathway. Notwithstanding, most important is prognosis definition, and the findings are summarized. Abnormal BAEP implies bad prognosis, as would be expected considering the severity of a brainstem lesion; on the other hand, a normal BAEP per se does not allow a precise definition, resting on other EP the role prognosis characterization. SSEP if bilaterally normal or only mildly abnormal imply good prognosis; bilateral absence of SSEP thalamo-cortical components has always carried a bad prognosis, since younger patients may at best evolve into a persistent vegetative state; SSEP intermediary results are more often accompanied by variable evolution. FVEP results parallel those of SSEP.

[Auditory evoked potentials in the monitoring of 15 laser microsurgeries of the brain stem]. / Potencial evocado auditivo na monitorização de 15 microlaser cirurgias do tronco cerebral.

Based upon the results observed in 15 patients submitted to tumor resection by the CO2 microlaser technique and submitted to brain stem auditive evoked potential (BAEP) intraoperative determination, the authors emphasize the importance of the technique. BAEP during the intraoperative period and the ultrasonic control of removal of tumors proved useful in the 15 cases of brain stem tumors or tumor adherent to it. Morbidity and mortality are described, and the important changes in BAEP that precede bradycardia are detailed. The importance of advances obtained through BAEP in peroperative control in such surgeries is stressed.

Potencial evocado: generalidades. / Evoked potencials: generalities

Apos definir o metodo e conceituar brevemente os 3 tipos principais de potencial evocado (visual, auditivo e somatossensitivo), sao discutidos aspectos do registro do PE, bem como as caracteristicas gerais dos sistemas utilizados nesse registro, procurando-se ressaltar a importancia fundamental de cada laboratorio de eletrofisiologia clinica proceder a normalizacao do metodo, antes de sua utilizacao no exame de pacientes. Por fim, sao citados alguns exemplos mais comuns de patologias onde a avalicao pelos PE acrescenta importantes subsidios ao diagnostico

Potencial evocado visual por padrao reverso. / Visual evoked potencial pattern reversal

Em 10 individuos normais de ambos os sexos foram estudados potenciais evocados visuais por padrao reverso (PEV-PR) com diferentes angulos visuais. Apos os estimulos monoculares, foram obtidas curvas reprodutiveis, apresentando componentes de latencias bem definidas, negativo ao redor dos 75 ms (N75), positivo ao redor dos l00 ms (Pl00) e negativo ao redor dos 120 ms (N120). Os dados normativos obtidos mostraram-se concordantes com os referidos na literatura consultada, permitindo assim a utilizacao do estudo do PEV-PR na avaliacao objetiva de patologias das vias opticas. Sao discutidas constancia e variabilidade dos componentes, bem como alteracoes introduzidas pelos diferentes angulos visuais estudados

Potencial evocado auditivo:tronco cerebral (estudo normativo). / Auditory evoked potentials:brain stem (normative study)

Em 10 individuos normais, adultos, de ambos os sexos, foram estudados os potenciais evocados auditivos - tronco cerebral (PEA-TC) usando-se cliks monoaurais por rarefacao com 60dB nivel de sensacao; o registro foi realizado em um canal, entre o vertex e a orelha ipsilateral. Os picos positivos, proeminentes e constantes no vertex foram numerados em algarismos romanos de I a VII, de acordo com a ja classica nomenclatura proposta por Jewett. Foi dada enfase ao estudo das latencias interpicos (LIP), particularmente I-III (tempo de conducao bulbo-pontino), III-V (tempo de conducao ponto-mesencefalico), I-IV e I-V (tempo de conducao central). Foram discutidas constancia e variabilidade das ondas, assim como aspectos gerais relativos a amplitude e morfologia. Os dados normativos obtidos mostraram-se concordantes com os referidos na literatura medica consultada, permitindo assim a aplicacao clinica do estudo dos PEA-TC na avaliacao objetiva de patologias interessando primaria ou secundariamente as vias auditivas no tronco cerebral