[The early postoperative period in patients with tumors of the posterior cranial fossa]. / Rannii posleoperatsionnyi period u bol'nykh s opukholiami zadnei cherepnoi iamki.

The studies carried out during an early postoperative period in patients with posterior fossa tumors were made to analyse the role of the degree and the level of brain stem damages in formation of cerebral reactions. The three groups of cases were selected in accordance with the course of the postoperative period: 1.1-with exitus letalis (irreversible damages); 1.2-rehabilitation in persistent focal damages; 2-restoration with functional safety of brain stem. Differences of the integral cerebral reactions (the state of consciousness, emotional-affective disorders, awakening state) as well as the brain stem syndromes (formation of pathological systems, reciprocal relations between intact and destroyed brain stem structures) and diencephalic-subcortical syndromes were considered.

[The effect of the brain stem structures on the shaping of the functional state of the human cerebral hemispheres (data from complex clinico-electroencephalographic and neuropsychological research)]. / Vliianie stvolovykh struktur na formirovanie funktsional'nogo sostoianiia bol'shikh polusharii golovnogo mozga cheloveka (dannye kompleksnogo kliniko-élektroéntsefalograficheskogo i neiropsikhologicheskogo issledovaniia).

To study the influence of the brainstem on formation of the functional state of the left and right brain hemispheres clinical electrophysiological examination of 13 patients with focal brainstem lesions (neurinoma of the auditory nerve) was carried out before and after surgery. The result were compared with neuropsychological data. Definite correlation was revealed between the changes in coherent structure of EEG and neuropsychological estimation of the functional state of brain areas. The brainstem was shown to be more intimately functionally connected with the left hemisphere than with the right one. The regional specificity within the left hemisphere was determined by the form of cerebral decompensation.

[Computed tomography in the diagnosis of complications in the early postoperative period in patients with tumors of the posterior cranial fossa]. / Komp'iuternaia tomografiia v diagnostike oslozhnenii v rannem posleoperatsionnom periode u bol'nykh s opukholiami zadnei cherepnoi iamki.

The authors analyse the results of clinico-CT studies in complicated course of the early postoperative period in 104 patients (87 adults and 17 children) with tumors of the posterior cranial fossa (PCF). According to the histological structure and predominant topography of the neoplasm, the cases were divided into 46 extracerebral parastem tumors (meningiomas, neurinomas, chordomas, cholesteatomas) among which 24 extended supratentorially and 22 to Blumenbach's clivus; 23 gliomas of the cerebellum and fourth ventricle; 16 primary gliomas of the stem; 19 other new growths (hemangioblastomas, hamartomas, choroid papillomas, germinomas). A common factor was coexistence of the main complicating condition--circulatory disorder in the stem with edema and dislocation of the stem, disturbed spatial relations between the PCF structures. Dynamic CT studies allowed the authors to differentiate 3 main variants of pathological changes differing in the character of cerebral circulatory disorders: 1st--a wide zone of reduced density in the brain stem; the extent of this zone in the orocaudal direction and its relation to the diameter of the stem (dorsal, ventral, lateral parts) varied; 2nd--combination of zones of reduced density in the stem and cerebellum with hemorrhagic inclusions--multiple "punctate" inclusions or in the form of blood clots; 3rd--in mosaic pattern of the ischemic foci in the stem and cerebellum there was a prevalence of hemorrhages in the form of multiple small extravasations of blood at different levels of the stem, in the subcortical parts, blood clots in the seat of the tumor, hemotamponade of the brain ventricles.(ABSTRACT TRUNCATED AT 250 WORDS)

[The intercentral relations of cortical bioelectrical activity in the human brain after surgical interventions on brain stem formations]. / Mezhtsentral'nye otnosheniia korkovoi bioélektricheskoi aktivnosti mozga cheloveka posle operativnogo vmeshatel'stva na stvolovykh obrazovaniiakh.

In the process of dynamic study of cortical bioelectrical activity and indices of its intercentral interaction in 52 neurosurgical patients with focal lesion on the brainstem level, the dependence was shown of the CNS reactions to the operative intervention on the character and degree of damage. Variants were described of compensatory neurodynamic reconstructions of electrical processes in observations with transient, stable and irreversible pathological foci of brainstem localization.

[The locked-in patient and the characteristics of the electrical activity of his brain]. / "Zapertyi chelovek" (locked-in) i osobennosti élektricheskoi aktivnosti ego golovnogo mozga.

"Locked-in" state differs from the known states characterized by the motor activity blockade, preservation of conscience of speech contact, despite the fact that connection with outer world during this state is limited only by vertical movements of eyes and eyelids in response to speech signals. Three "locked-in" men were studied at different stages of development of this state. Spectral-coherent analysis of the EEG was conducted. The most typical for the developed state of the "locked-in" man is a uniform change of the intercentral EEG relations. In the motor areas of the cortex alpha-activity and its links are not formed (coherence in alpha-range is zero) while high and low frequencies are coherent. In the visual areas, in contrast, the alpha-rhythm is coherent. Distinct interhemispheric asymmetry of coherent connections appears. In the right hemisphere a decrease of coherence level is sharp and even, in the left one--in occipito-temporal parts the level remains close to norm, while in the frontal parts of the cortex it decreases.