Brainstem auditory evoked potentials (BAEPs) pathology in topographical diagnosis of posterior fossa lesions.

The authors tried to determine the level of the brainstem where possible generators of various BAEPs waves could be situated by correlating clinical neurological symptomatology and/or cranial computed tomography findings of 195 patients with posterior fossa lesions with distinct BAEPs waves pathology. Results of statistical analysis showed a significant dependence between the levels of lesions as revealed by clinical symptomatology and/or cranial computed tomography and distinct BAEPs waves I-V pathology. Only indirect proof exists for the supratentorial origin of waves VI and VII. Because of the frequently normal function of hearing, as revealed by routine audiometry, in every group of patients with distinct BAEPs waves pathology, the authors also suggest that structures not involved in behavioral mechanisms of hearing could participate in BAEPs waves generation.

Pathology of wave III of brainstem auditory evoked potentials (BAEPs).

In a group of 195 consecutively examined patients with brainstem neurological symptomatology parameters of the wave III BAEPs were pathological in 20 patients. In 70% of them the clinical symptomatology and/or the cranial computed tomography examination results pointed to a lesion at the level of pontomedullary junction and lower pons Varoli where according to the recent opinion the possible generators of this BAEP wave are situated (superior olivary complex, nuclei cochleares, corpus trapezoideum). These results support the supposed localization of possible generators of the wave III BAEPs.

Neuroscience in Czechoslovakia.

The collapse of the communist regime in Czechoslovakia revealed not only the disastrous state of the Czechoslovak economy but also the serious problems that Czechoslovak science faces. Understanding the present situation and determining the best way to improve it requires careful analysis of the development of science during the past 40 years.

Trace element distribution in human eye.

A hundred samples of four types of eye tissues and hair from a set of 10 donors from the city of Prague were analyzed using INAA. The hair samples of the set of donors were taken as the indicator of the environmental conditions. Within the framework of the set of results obtained for 30 chosen elements, the differences between various types of tissues and sex were tested. The lowest trace element deposition was found for the lens tissue. The iris differs predominantly by the higher contents, particularly of metal elements. Slightly higher contents of practically all trace elements under study were found in all eye tissues taken from male donors.

[Diplopia in fractures of the orbital floor]. / Diplopie u zlomenin spodiny ocnice.

Based on their own experience with surgical treatment of 43 patients with fractures of the orbital floor, the authors discuss the problem of early operation in relation to the development of residual diplopia. They evaluate the functional result by the size of the visual field where diplopia occurred. In confirmed fractures of the orbit they recommend operation as early as possible after the injury. All patients were operated by the method of transantral reposition of the orbital floor. Satisfactory functional results were achieved in all operated patients. None of them had diplopia in the primary position of the eyes. The best results were achieved in patients operated early (residual diplopia in 10%), where none of the patients had diplopia in the visual field beneath 30 degrees.

[Prophylactic treatment of vasospasm with nimodipine in subarachnoid hemorrhage]. / Profylaktická liecba vazospazmu nimodipinom u subarachnoideálneho krvácania.

Nimodipine, a calcium antagonist, was administered to 33 patients with subarachnoidal haemorrhage as prophylaxis of late ischaemic neurological deficiency. Despite the relatively high frequency of vasospasm during repeated angiographic examinations (27%), the general therapeutic effect in the group of treated patients was favourable. 52% patients improved and had no or only a minimal neurological deficit. Possible mechanisms of the favourable effect of nimodipine in subarachnoidal haemorrhage are mentioned in the discussion.

Brainstem auditory evoked potentials (BAEPs), pathology of wave IV.

In a group of 134 consecutive patients with brainstem symptomatology wave IV was bilaterally absent in 69%. Bilateral absence of this wave can be considered as a normal state. Only absence of wave IV on one side with its presence on the other side was appraised as pathologic. Asymmetries of the latency and amplitude could not be taken into consideration because of the lack of normative data for this wave. Computer tomography showed in our pathologic cases lesions in the pons, oblongata and cerebellum. The clinical semiology was extensive and multiform pointing in 84% to a pontine origin, in 16% to a lesion of the midbrain or oblongata. A possible lesion of the pons was in accordance with its functional anatomy as well as with the supposed origin of wave IV (superior olivar complex, lateral lemniscal nucleus). In 62% of cases the pathology of wave IV was present without impairment of auditory functions. The pathology of wave IV was considered as little sensitive and little specific.

[Periodic discharges in clinical electroencephalography]. / Periodické výboje v klinickej elektroencefalografii.

The authors recorded generalized and focal periodic discharges in 49 EEG tracings from 27 patients aged 5 to 75 years. According to the shape of the waves and their complexes generalized periodic discharges were formed by slow waves, sharp waves or spikes, triphasic waves and periodic activity of the "suppression burst" type. Focal periodic discharges had the shaps of slow waves and so-called periodic lateralized epileptiform discharges. Six patients suffered from Creutzfeldt-Jacob's disease and from herpetic encephalitis. Four had an acute cerebrovascular attack. Three suffered from subacute sclerotizing panencephalitis. Other conditions found included metabolic brain damage, post-traumatic purulent meningitis, anoxic encephalopathy and partial motor convulsions. Different types of periodic discharges were found in the same disease and even in the same patient and conversely one type of periodic discharges is found in different diseases. The authors assume that periodic discharges are not specific, have a different aetiology but obviously a common pathophysiological mechanism. From the EEG alone conclusions on the aetiology can be drawn only with a limited probability. It is necessary to use a comprehensive approach in their evaluation, taking account age, the clinical picture and development as well as results of other examinations. The 70.3% mortality in the group provides evidence that periodic discharges are a serious finding as regards the prognosis of the disease.