[Objective auditory evaluation by evoked potentials]. / Avaliação auditiva objetiva através de potenciais evocados.

We have analyzed 1300 Auditory Brain-Stem Response Audiometry exams. The patients were distributed according to criteria related to age, clinical presentation, hearing impairment risk-factors and hearing thresholds. The results were divided into five groups of hearing thresholds: normal hearing (threshold response obtained up to 25 dBHL); mild hearing loss (25-50 dBHL); moderate hearing loss (50-70 dBHL); severe hearing loss (70-90 dBHL); and without response to acoustic stimuli. We have studied the risk-factors related to gestation, delivery and neonatal period, family history of hearing loss, hearing apparatus malformations, craniofacial anomalies, certain modalities of infectious diseases, hearing impairment associated syndromes, and the use of some kind of drugs. Cerebral palsy, neuropsychomotor development retardation and cases without known antecedents were also studied. The main results of our study show: 82.8% incidence of hearing impairment; the late performance of examinations to evidence a definite hearing loss as 54.1% of the examined patients were at ages ranging from one to three years old; 54.0% of total cases have not presented any language development; the risk-factor "Congenital Rubeola" has the expressive incidence of 14.8% and the distribution of this value into hearing threshold ranges has shown an exponential increase which demonstrates a close correlation between that disease and hearing impairment.

[Multiple sclerosis: objective criteria of diagnosis]. / Esclerose múltipla: critérios objetivos de diagnóstico.

The frequency of multiple sclerosis in Brasil is assumed to be lower than in some geographically comparable regions, but internationally available objective diagnostic criteria are not generally used. We have reviewed a number of such criteria and applied those of Poser and colleagues to all patients who could be examined specifically for this study; who had been under our care between 1982-87; with clinically satisfactory history, physical exam, ancillary investigations and follow-up; with enough information to warrant immunosuppressive therapy with azathioprine, methyl-prednisolone or cyclophosphamide. There were 35 (88%) females and 5 (12%) males, with clinically definite (85%), probable (10%) disease according to Poser and cols, as well as 2 patients with chronic progressive disease. Age at time of study was 39 +/- 11 years, age at onset had been 32 +/- 10 years, and length of history was 6 +/- 7 years (mean +/- sd). Mode of onset was a disturbance of gait in 50%, of vision in 25% and dizziness in 10%. Physical exam at time of study showed motor deficits in 92.5%, sensory in 67.5%, ocular visual in 65%, spastic bladder in 35%, and vestibulo-cerebellar disturbances in 32%. Visual evoked responses were abnormal in 65% of 31 cases, auditory in 23% of 22 cases, and somatosensory in 80% of 20 cases. This study shows that international diagnostic criteria, specifically those of Poser and colleagues are applicable in Brasil, providing clear guidelines for diagnosis of multiple sclerosis. We suggest objective diagnostic criteria form the backbone of teaching about the disease, at various levels of medical education. Their wide utilization will in due time provide conditions for epidemiological, clinical and therapeutic studies which have not as yet been carried out in this country.

[Spinal cord infarction: clinical, electrophysiologic and laboratory diagnosis]. / Infarto medular: diagnóstico clínico, eletrofisiológico e laboratorial.

In the international, but more so in the latin-american, medical literature infarction of the spinal cord has been rarely described except in relationship with surgery of the abdominal aorta. The objective of this report is to describe the diagnostic approach including clinical, electrophysiological, imaging and cerebrospinal fluid criteria. With these methods 17 cases were diagnosed between 1982 and 1989, one related to surgery of the abdominal aorta. This series suggests that infarction of the spinal cord is a more common clinical entity than presently considered. Its rarity may be due to a high diagnostic threshold related to the perception that there is no specific therapy.

[Thymectomy and immunosuppression in myasthenia gravis: a prospective study]. / Timectomia e imunossupressão em miastenia gravis: estudo prospectivo.

Between 1982 and 1988 24 women and 6 men with myasthenia gravis were included in a prospective and standardized diagnostic and therapeutic protocol. Age varied between 10 and 74 years (34 +/- 16, mean +/- standard deviation). Three patients with the ocular form were treated with pyridostigmine. Four patients with the generalized form and advanced age received steroids and/or azathioprine. Twenty-three patients with the generalized form underwent thymectomy followed by prednisone and/or azathioprine. One patient died after complex thymectomy for invasive thymoma. Another died soon after admission in myasthenic/cholinergic crisis. Two other patients had minor complications of thymectomy. Of 19 patients followed for 1-60 (mean 24) months, 11 (58%) are in remission, one of them without any medication.

Mitochondrial myopathy and myoclonic epilepsy.

The authors describe a family (mother, son and two daughters) with mitochondrial myopathy. The mother was asymptomatic. Two daughters had lactic acidosis and myoclonic epilepsy, mild dementia, ataxia, weakness and sensory neuropathy. The son suffered one acute hemiplegic episode due to an ischemic infarct in the right temporal region. All the patients studied had hypertension. EEG disclosed photomyoclonic response in the proband patient. Muscle biopsy disclosed ragged-red fibers and abnormal mitochondria by electron microscopy. Biochemical analysis showed a defect of cytochrome C oxidase in mitochondria isolated from skeletal muscle. Several clinical and genetic aspects of the mitochondrial encephalomyopathies are discussed.

Anestesia quantitativa em sistema fechado. / Quantitative anesthesia in closed circuit

Os autores, considerando a poluicao ambiental e a consequente necessidade de se instalar equipamentos caros e nem sempre eficientes para eliminar o ar expirado pelos pacientes, preconizam o uso de sistemas fechados e com baixos fluxos de gases para administracao de anestesia inalatoria Procuram demonstrar em seu trabalho, que a tecnica preconizada por Lowe e estimulante, pois nao requer equipamentos sofisticados, e os calculos matematicos podem ser perfeitamente simplificados. Chamam principalmente atencao a nao necessidade de equipamentos, tais como vaporizadores calibrados de alto custo, e da economia que este tipo de anestesia traz para os pacientes. Acreditam que seja mais difundida principalmente nos paises em desenvolvimento