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Cerebral ischemia is a frequent and dangerous consequence of some cerebrovascular diseases. Ischaemia may be used also electively in the course of neurosurgery. Therefore new possible ways are sought how to reduce the danger of ischaemia or to prevent it. In the submitted paper some methods of neuroprotection are described and their potential or actual applicability in clinical neurosurgery are discussed. In addition to influencing the brain cell and pretentious methods in the sphere of molecular biology and genetics the induction of systemic hypertension supplemented alternatively by other methods such as hypothermia, the use of mannitol, haemodilution and hypervolaemia seem natural. A higher blood pressure helps to make leptomeningeal and cortical anastomoses patent and strengthens the collateral circulation from marginal zones of ischaemia, penumbra to the ischaemic centre and to prevent thus cerebral infarction.

The authors refer in their paper to previous discussions on methodological problems associated with the application of Doppler continuous ultrasonography in neonatological practice. The methodological investigation was made in a group of twelve neonates with a mean birth weight of 2028 g and gestational age of 33.3 weeks. All were examined at the age of three weeks when the postpartum adaptation is already completed and the clinical condition is stabilized. After perfect mastering of the technique of measurement, the authors found that the mean error of assessment of PI on the internal carotid artery was 3.6%, on its siphon 2.7% and on the anterior cerebral artery 2.7%. The mean error of measurement for MVF on the same arteries was 7.7%, 13.7% and 6.1% resp. The greatest error was for EDFV on the internal carotid artery 11.7% on its siphon 15.8% and on the anterior cerebral artery 6.1%. The smallest mean error of assessment of all three parameters was on the anterior cerebral artery, the greatest error on the siphon of the internal carotid artery. On the investigated arteries no significant lateral difference was recorded. The mean values of PI, MFV and EDFV have a declining trend in the direction towards the periphery, i.e. in the direction from the internal carotid artery to the anterior cerebral artery. These trends were also confirmed in individual children. The authors assume that the method of continuous Doppler ultrasonography is despite limitations, inherent to its nature, suited for use in neonatological practice.