[Clinical and neurochemical aspects of diaphragmatic myoclonus]. / Aspectos clínicos y terapéuticos de las mioclonías diafragmáticas.

The case of a 35-year-old woman with diaphragmatic myoclonus of four year duration is presented. The myoclonus deteriorated with anxiety, menstruation and orthostatism. It was frequently accompanied by urinary retention or incontinence. Several pharmacologic agents were shown to be ineffective until the myoclonus was suppressed with a combination of gabapentin and tiagabine. In this article, the respiratory center is proposed as the original focus of the myoclonus, a deficit of gamma-aminobutyric acid (GABA) in brainstem structures as its neurochemical substrate, and GABAergic enhancement as an effective therapeutic measure. The clinical manifestations, etiology, ancillary studies and treatment of diaphragmatic myoclonus are reviewed. Experimental evidence on the anatomical localization, physiology and neurochemistry of the respiratory center is examined. The authors try to relate some of the patient's clinical findings to the experimental data found in the medical literature. The action mechanisms of gabapentin and tiagabine are examined and these drugs are proposed as effective means of enhancing GABAergic neurotransmission and treating diseases with increased inspiratory drive.

[Painful tonic seizures in multiple sclerosis. Clinical and electromyographic aspects (author's transl)]. / Crisis tónico-dolorosas en la esclerosis múltiple: aspectos clínicos y electromiográficos.

This case report deals with a 29 year-old female patient with a prior history of a vestibular syndrome and elapsing optic neuritis that presented paroxystic episodes of painful tonic contractions affecting the right hemibody, especially the upper limb. In the hand the clinical picture was similar to that of the carpal spasm of tetany. When inducing a crisis with ischemia the electromyogram showed diplets, triplets, and multiplets following the appearance of an interference pattern syncronous with contraction of the hand. Occasionally an interference pattern was observed that was associated only to a subjective sensation of paresthesia. During the crisis and in the intercritical periods the following measurements gave normal results: serum calcium, phosphorus, sodium, potassium, magnesium, pH, and pCO2. The administration of calcium had no effect on the frequency and intensity of the crisis. The response to carbemazepine was dramatic, with complete cessation of the crisis and disappearance of the spontaneous activity in the electromyogram. Interruption of treatment one year later was followed by relapse of the painful tonic crisis. The importance of certain electromyographic features and the therapeutic response to carbemazepine in the differential diagnosis of painful tonic crisis and tetany are emphasized. The existence of two clinical-electromyographic patterns in painful tonic crisis is pointed out.

[Non-surgical forms of cerebellar hematoma (author's transl)]. / Hematoma de cerebelo. Formas no quirúrgicas.

Spontaneous cerebellar hemorrhage is a significant clinical entity because of its important incidence (more than 10 percent of intracranial hemorrhages) and its therapeutic possibilities. The diagnosis of this condition is difficult, but at the presnet time the Emi-scanner easily confirms the diagnosis. The surgical treatment was up until recently the only possible therapeutic approach, and it has been indiscriminately applied to all patients because of the high mortiality rate of this condition (80 percent). Two hypertensive patients who presented spontaneous cerebellar hematomas, verified by the scanner, were not submitted to surgery and both recovered spontaneously without sequelae. The existence of non-surgical forms of spontaneous cerebellar hemorrhage is discussed. Special attention is placed upon the variations in the level of consciousness and the presence or absence of acute hydrocephalus in the scanner in order to indicate the convenience of a surgical procedure.