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Eye movement during blinking can be a significant artifact in Event-Related Potentials (ERP) analysis. Blinks produce a positive potential in the vertical electrooculogram (VEOG), spreading towards the posterior direction. Two methods are frequently used to suppress VEOGs: linear regression to subtract the VEOG signal from the electroencephalogram (EEG) and Independent Component Analysis (ICA). However, some information is lost in both. The present algorithm (1) statistically identifies the position of VEOGs in the frontopolar channels; (2) performs EEG averaging for each channel, which results in 'blink templates'; (3) subtracts each template from the respective EEG at each VEOG position, only when the linear correlation index between the template and the segment is greater than a chosen threshold L. The signals from twenty subjects were acquired using a behavioral test and were treated using FilterBlink for subsequent ERP analysis. A model was designed to test the method for each subject using twenty copies of the EEG signal from the subject's mid-central channel (with nearly no VEOG) representing the EEG channels and their respective blink templates. At the same 200 equidistant time points (marks), a signal (2.5 sinusoidal cycles at 1050 ms emulating an ERP) was mixed with each model channel and the respective blink template of that channel, between 500 to 1200 ms after each mark. According to the model, VEOGs interfered with both ERPs and the ongoing EEG, mainly on the anterior medial leads, and no significant effect was observed on the mid-central channel (Cz). FilterBlink recovered approximately 90% (Fp1) to 98% (Fz) of the original ERP and EEG signals for L = 0.1. The method reduced the VEOG effect on the EEG after ERP and blink-artifact averaging in analyzing real signals. The method is straightforward and effective for VEOG attenuation without significant distortion in the EEG signal and embedded ERPs., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Marques Abramov et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Some children with severe microcephaly related to Zika virus infection show affective social-like behavior, such as smiling and rejection to a stranger's lap. Our objective was to check the association between this behavior and the occurrence of Mismatch Response (MMR) in event-related potentials. Twenty eight microcephalic children, aged 1-3 years, were divided in Affect(+) and Affect(-) groups, according to either the presence or absence of affective social-like behavior, respectively, and underwent the OddBall paradigm with vowels as auditory stimuli. MMR was statistically estimated comparing MMR sample means between both groups. The Affect(+) group significantly differed from the Affect(-) group and, as opposed to the latter, showed MMR as Mismatch Negativity (MMN) in the left occipital, left and right posterior temporal, and (especially) the right and median parietal leads. The relationship observed between MMN and affective social-like behavior suggests that these children may have cognitive mechanisms capable of providing some social interaction, despite their profound neurological dysfunction. MMN diagnostic techniques seem to be promising for the triage of microcephalic subjects regarding cognitive functions and for choosing a strategy for some social adaptation., Competing Interests: Declaration of competing interest All authors declare that there are no conflicts of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Electroencephalography (EEG) as a biomarker of neuromodulation by High Definition transcranial Direct Current Stimulation (HD-tDCS) offers promise as both techniques are deployable and can be integrated into a single head-gear. The present research addresses experimental design for separating focal EEG effect of HD-tDCS in the '4-cathode × 1-anode' (4 × 1) montage over the left motor area (C3). We assessed change in offline EEG at the homologous central (C3, C4), and occipital (O1, O2) locations. Interhemispheric asymmetry was accessed for background EEG at standard frequency bands; and for the intermittent photic stimulation (IPS). EEG was compared post- vs pre-intervention in three HD-tDCS arms: Active (2 mA), Sham (ramp up/down at the start and end), and No-Stimulation (device was not powered), each intervention lasting 20 min. The asymmetric background EEG changes were only in the central areas with right-side amplitude spectra prevalence, most pronounced in the no-stimulation arm, where they depended on comparison time-points and were consistent with markers of transition between drowsiness and vigilance - bilateral decrease in the delta and asymmetric central increase in the alpha and beta1 bands. For the active arm, similar but less pronounced changes occurred in the alpha band. In contrast, responses to IPS developed similar asymmetric amplitude increase at four harmonics of the IPS of 3 Hz only in the active arm, against a background of a brain-wide symmetric increase in both active and sham arms. Our protocols and analyses suggest methodological caveats for how EEG of tDCS studies could be conducted to isolate putative brain polarization outcomes., (Copyright © 2019 IBRO. Published by Elsevier Ltd. All rights reserved.)

In Attention Deficit Hyperactivity disorder (ADHD), fMRI studies show asymmetric alterations: widespread hypoactivation in anterior cortical areas and hyperactivation in some posterior regions, and the latter is considered to be related to compensatory processes. In Posner's attentional networks, an important role is attributed to functional interhemispheric asymmetries. The psychophysiological Attention Network Test (ANT), which measures the efficiency of the alerting, orienting, and executive networks, seems particularly informative for ADHD. Potentials related to ANT stimuli (ANT-RPs) have revealed reduced cognitive potential P3 in ADHD. However, there are no studies associated with asymmetry of ANT-RPs. In the present study, conducted with 20 typically developing boys and 19 boys with ADHD, aged 11-13 years, the efficiency of the three Posner's networks regarding performance and amplitude asymmetries in ANT-RPs was evaluated according to the arithmetic difference of these parameters between different cue and target presentation conditions. The results were correlated to Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) scores. Regarding accuracy and intraindividual variation in reaction time, ADHD subjects showed lower efficiency of executive and alerting network, and this effect was correlated with DSM. Regarding alerting network, ANT-RPs in ADHD did not have the right-side amplitude prevalence in the temporal regions, which was observed in controls. In all ANT conditions, significantly higher asymmetries were observed in ADHD than in controls in the occipital regions 40-200 ms after target onset. Their amplitude in ADHD subjects was inversely proportional to DSM scores of inattentiveness and directly proportional to accuracy and efficiency of the executive network. The results suggest impaired alerting and executive networks in ADHD and compensatory occipital mechanisms., Competing Interests: The authors have declared that no competing interests exist.

Objective: To estimate whether the "Diagnostic and Statistical Manual of Mental Disorders" (DSM) is biologically accurate for the diagnosis of Attention Deficit/ Hyperactivity Disorder (ADHD) using a biological-based classifier built by a special method of multivariate analysis of a large dataset of a small sample (much more variables than subjects), holding neurophysiological, behavioral, and psychological variables., Methods: Twenty typically developing boys and 19 boys diagnosed with ADHD, aged 10-13 years, were examined using the Attentional Network Test (ANT) with recordings of event-related potentials (ERPs). From 774 variables, a reduced number of latent variables (LVs) were extracted with a clustering of variables method (CLV), for further reclassification of subjects using the k-means method. This approach allowed a multivariate analysis to be applied to a significantly larger number of variables than the number of cases., Results: From datasets including ERPs from the mid-frontal, mid-parietal, right frontal, and central scalp areas, we found 82% of agreement between DSM and biological-based classifications. The kappa index between DSM and behavioral/psychological/neurophysiological data was 0.75, which is regarded as a "substantial level of agreement"., Discussion: The CLV is a useful method for multivariate analysis of datasets with much less subjects than variables. In this study, a correlation is found between the biological-based classifier and the DSM outputs for the classification of subjects as either ADHD or not. This result suggests that DSM clinically describes a biological condition, supporting its validity for ADHD diagnostics., Competing Interests: The authors declare there are no competing interests.

Objective: To study the effect of prenatal Zika virus (ZV) infection on brainstem function reflected in brainstem auditory evoked potentials (BAEPs)., Methods: In a cross-sectional study in 19 children (12 girls) with microcephaly related to ZV infection, aged between 12 and 62 weeks, the brainstem function was examined through BAEPs. The latencies of wave peaks I, III, and V of the left and right ears (n = 37) were standardized according to normative data, and compared between them by 2-tailed t test. The confounding variables (cephalic perimeter at the born and chronological age) were correlated with the normalized latencies using Pearson test., Results: All patients showed, in general, clear waveforms, with latencies within 3 SDs of the normative values. However, statistically increased latencies of waves I and III (I > III, p = 0.031) were observed, relative to wave V ( p < 0.001), the latter being closer to respective normative value. The latency of wave I was observed to increase with age ( r = 0.45, p = 0.005). The waves, in turn, did not depend on cephalic perimeter., Conclusions: These results are consistent with the functional normality of the brainstem structure and its lack of correlation with microcephaly, suggesting that the disruption produced by the ZV infection does not act in the cell proliferation phase, but mostly in the processes of neuronal migration and differentiation in the telencephalon., (© 2018 American Academy of Neurology.)

In ERP studies of cognitive processes during attentional tasks, the cue signals containing information about the target can increase the amplitude of the parietal cue P3 in relation to the 'neutral' temporal cue, and reduce the subsequent target P3 when this information is valid, i.e. corresponds to the target's attributes. The present study compared the cue-to-target P3 ratios in neutral and visuospatial cueing, in order to estimate the contribution of valid visuospatial information from the cue to target stages of the task performance, in terms of cognitive load. The P3 characteristics were also correlated with the results of individuals' performance of the visuospatial tasks, in order to estimate the relationship of the observed ERP with spatial reasoning. In 20 typically developing boys, aged 10-13 years (11.3±0.86), the intelligence quotient (I.Q.) was estimated by the Block Design and Vocabulary subtests from the WISC-III. The subjects performed the Attentional Network Test (ANT) accompanied by EEG recording. The cued two-choice task had three equiprobable cue conditions: No cue, with no information about the target; Neutral (temporal) cue, with an asterisk in the center of the visual field, predicting the target onset; and Spatial cues, with an asterisk in the upper or lower hemifield, predicting the onset and corresponding location of the target. The ERPs were estimated for the mid-frontal (Fz) and mid-parietal (Pz) scalp derivations. In the Pz, the Neutral cue P3 had a lower amplitude than the Spatial cue P3; whereas for the target ERPs, the P3 of the Neutral cue condition was larger than that of the Spatial cue condition. However, the sums of the magnitudes of the cue and target P3 were equal in the spatial and neutral cueing, probably indicating that in both cases the equivalent information processing load is included in either the cue or the target reaction, respectively. Meantime, in the Fz, the analog ERP components for both the cue and target stimuli did not depend on the cue condition. The results show that, in the parietal site, the spatial cue P3 reflects the processing of visuospatial information regarding the target position. This contributes to the subsequent "decision-making", thus reducing the information processing load on the target response, which is probably reflected in the lower P3. This finding is consistent with the positive correlation of parietal cue P3 with the individual's ability to perform spatial tasks as scored by the Block Design subtest., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In search for the functional counterpart of the alternative Probst and sigmoid bundles, considered as morphological evidence of neuroplasticity in callosal dysgenesis, electroencephalographic (EEG) coherence analysis was combined with high resolution and diffusion tensor magnetic resonance imaging. Data of two patients with callosal agenesis, plus two with typical partial dysgenesis with a remnant genu, and one atypical patient with a substantially reduced genu were compared to those of fifteen neurotypic controls. The interhemispheric EEG coherence between homologous nontemporal brain regions corresponded to absence or partial presence of callosal connections. A generalized coherence reduction was observed in complete acallosal patients, as well as coherence preservation in the anterior areas of the two patients with a remnant genu. jThe sigmoid bundles found in three patients with partial dysgenesis correlated with augmented EEG coherence between anterior regions of one hemisphere and posterior regions of the other. These heterologous (crossed) interhemispheric connections were asymmetric in both imaging and EEG patterns, with predominance of the right-anterior-to-left-posterior connections over the mirror ones. The Probst bundles correlated with higher intrahemispheric long-distance coherence in all patients. The significant correlations observed for the delta, theta and alpha bands indicate that these alternative pathways are functional, although the neuropsychological nature of this function is still unknown.

The EEG coherence among 14 scalp points during intermittent photic stimulation at 11 fixed frequencies of 3-24 Hz was studied in 14 boys with autism, aged 6-14 years, with relatively intact verbal and intellectual functions, and 19 normally developing boys. The number of interhemispheric coherent connections pertaining to the 20 highest connections of each individual was significantly lower in autistic patients than in the control group at all the EEG beta frequencies corresponding to those of stimulation. The coefficient of coherence values between homologous occipital, parietal and central areas at the same frequencies were also lower in the autistic group in both mono- and bipolar montages due to a deficit in reactive photic driving increase. No differences between the groups were observed in the spontaneous EEG.

Design: A randomized prospective study., Patients and Methods: The study included 87 children aged from 5 to 18, ASA I-II. The patients were divided into two groups. We assessed the impact of reamberin 1.5% (succinate-containing infusion solution) on the level of metabolism and recovery after surgery in patients of main group (n = 44) and control group (n = 43) during different surgeries. All patients received general anaesthesia with sevoflurane, fentanyl, and rocuronium., Results: Reamberin 1.5% promotes to increase the level of basal metabolism in the early postoperative period, decreases the duration of awakening periods, improves recovery of motor activity and adequate breathing.

The present paper reports a clinical case of local syphilitic meningoencephalitis known as Argyll-Robertson syndrome and manifested in the form of acute sensorineural loss of hearing. The patient was a 46 year old resident of the city of Irkutsk. He experienced the sharp impairment of hearing involving both ears with the accompanying feeling of dizziness, disturbed orientation of the locomotorbehaviour, the lurching gate, subfebrility, the loss of the ability to speak and write. The diagnosis was based on the presence of anisocoria, the absence of consensual pupillary reaction to the light, weak atropine action on the pupils, well expressed positive results of the VRDL (blood) and RW (liquor) tests, an enhanced signal from the left temporal region in the T-2 regime during MRI, positive hearing dynamics within 12 hours after the onset of anti-inflammatory, antibacterial and infusion therapy. The specific feature of the clinical case being considered is differential diagnostics was performed with the purpose of distinguishing it from otogenic brain abscess associated with chronic left-hand mesotympanitis.

Research Objective: To compare haemodynamic effects of general anaesthesia in combination with epidural block and without it during kidney transplantation in Pediatric patients., Methods: 61 Pediatric patients undergoing kidney transplantation were divided into two groups. General anaesthesia with sevoflurane, propofol, phentanilum and regional ropivacaine epidural block were used in the group 1. General anaesthesia was used only in the group 2. Haemodynamic parameters were assessed: Arterial blood pressure, stroke volume, central venous pressure and cardiac index., Results: Both techniques of anaesthesia were adequate., Conclusion: regional ropivacaine epidural block and general anaesthesia combination provides more stable haemodynamic parameters than general anaesthesia single use.

The effect of reamberin (1.5% solution of succinic acid and ion complex) on the oxygenation status of the brain was studied in children aged 1 - 14 years during recovery from anesthesia. It is established that reamberin in a dose of 2 ml/kg administered twice at the end of an operation increases the fraction of oxidized hemoglobin and cytochrome oxidase and enhances the regional saturation of brain tissue with oxygen, which is indicative of an increase in the potential of metabolism activation in neurons.

The study investigates the influence of Voluven 6% and HAES-steril 10% on the hemodynamics and organism water balance of 40 children from 3 months to 17 years of age, which were divided into two groups according to the type of the administered colloid. It is acquired that infusion of colloids with 1:3 ratio compared to crystalloids in general volume of infused liquids (Voluven 6% in the dose of 5 ml/kg/hour in case of median blood loss of 15% of the total circulating blood volume during two hour long surgery and HAES-steril 10% in the dose of 4 ml/kg/hour in case of the blood loss up to 25% of TCBV) allows to effectively neutralize hemodynamic changes based upon administration of anesthetic agents and intraoperative fluid loss. While administration of Voluven 6% is accompanied by significant, statistically accurate decrease of lower limb impedance, which indicates the increased amount of water in them, HAES-steril 10% administration leads to redistribution of water in the body segments with its predominant significant increase in the torso.

The research is based on the analysis of 50 cases of anesthesia during reconstructive surgeries in children. The anesthesia was based on inhalation of sevolflurane and injection of fentanyl by the bolus infusion scheme. During the different stages of anesthesia the opioid concentration in plasma was measured. Analysis of hemodynamic parameters showed no statistically significant differences in changes in performance, indicating the steady flow of anesthesia. Infusion of fentanyl provided a smooth, gradual decrease in its concentration in plasma, while analgesia remained adequate. The combination of sevoflurane in a concentration of 1.3 MAC and infusion of fentanyl to a total dose 6 mkg/kg/h was effective in provisioning stable anesthesia in the given category of patients with surgical pathology.

The possibility of using 1.5% succinic acid solution (reamberin) in order to activate recovery from anesthesia was studied in a group of 91 patients aged 1-14 years. Based on clinical data and BIS-index, it is established that the administration of reamberin during exit from anesthesia stage shortens the wake-up period, decreases the time of restoration of the motor activity and adequate respiration, and accelerates brain function recovery.

Objective: Examination of the EEG photic driving coherence during intermittent photic stimulation in autistic patients with relatively intact verbal and intellectual functions in order to enhance the likely latent interhemispheric asymmetry in neural connectivity., Methods: Fourteen autistic boys, aged 6-14years, free of drug treatment, with I.Q. 91.4+/-22.8, and 19 normally developing boys were subject to stimulation of 12 fixed frequencies of 3-27Hz. The number of high coherent connections (HCC) (coherence >0.6-0.8) was estimated among 7 leads in each hemisphere., Results: In contrast to the spectral characteristics showing the right hemisphere deficit in the photic driving reactivity, the number of HCC differentiated the groups only in the left hemisphere where it was higher in autistics at the EEG frequencies corresponding to those of stimulation at 6-27Hz without asymmetry at other frequencies, the left-side prevalence increasing with frequency. No asymmetry was observed in the resting state., Conclusions: Spectral and coherence characteristics of the EEG photic driving show different aspects of latent abnormal interhemispheric asymmetry in autistics: the right hemisphere "hyporeactivity" and potential "hyperconectivity" of likely compensatory nature in the left hemisphere., Significance: The EEG photic driving can reveal functional topographic alterations not present in the spontaneous EEG., (Copyright (c) 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)

The paper analyzes the publications dedicated to the problem of agitation after inhalation anesthesia with sevofluorane. A brief explanation of the conception "agitation" is given in the context of interpretation of explanatory and psychological dictionaries. According to most of the analyzed papers, it is concluded that the incidence of the postanesthetic agitation syndrome occurs after anesthesia with sevofluorane than after that with halothane. The leading risk factors of agitation are preschool age, significant psychoemotional lability in the preoperative period (difficult parting with parents), fear. The efficiency of the preventive measures given in the analyzed paper is disputable. These include opioids (fentanyl), benzodiazepines (midasolam), clonidine, ketamine, dexmedotomidine, nitrous oxide, propofol, etc. The authors conclude that this problem is of no high significance in the aspect of priority, the width and safety of sevofluorane use in the anesthetic maintenance of children although it by far needs further more detailed study.

In 14 autistic boys, aged 6-14 years, free of drug treatment, with relatively intact verbal functions and without severe or moderate mental retardation (I.Q. 91.4+/-22.8), intermittent photic stimulation at 11 fixed frequencies of 3-24 Hz revealed latent deficiency of the right hemisphere in the photic driving reactivity, predominantly at the fast alpha and beta frequencies of stimulation. The left-side prevalence was observed: 1) in the total number of driving peaks evaluated for the first four harmonics in the EEG spectra of 14 cortical areas and 2) in the driving amplitude in the spectra of the 2 occipital areas. As compared to 21 normally developing boys matched on age who did not show interhemispheric asymmetry in the driving reactivity, the autistic patients had significantly lower driving characteristics only in the right hemisphere. There were no significant differences between the autistic and control groups in the spontaneous EEG spectra of the occipital areas in the resting state.

The paper presents different investigators' data on the use of the bispectral (BIS) index in children during anesthetic maintenance and intensive care. The most of publications deal with the use of the BIS index during anesthesia with sevoflurane, which shows its high efficiency in estimating the depth of sleep. There are positive aspects in the use of the BIS index in the evaluation of sedative tolerance and central nervous system function, when brain death is diagnosed, cerebral oxygenation adequateness, etc. Data are given on the ambiguity of BIS index values in infants less than a year of age.

Amplified spontaneous emission intensity and gain spectra in polarized light have been measured in a dye doped nematic liquid crystal for different orientation of its optical axis and pump intensity. A possibility for switching the gain of the liquid crystal by an external electric field is shown experimentally. The liquid crystal materials with field controlled gain can be used in microlasers and light micro-amplifiers in both planar and waveguiding geometry.

In the present work, a commonly used index for evaluating the Event-Related Synchronization and Desynchronization (ERS/ERD) in the EEG was expressed as a function of the Spectral F-Test (SFT), which is a statistical test for assessing if two sample spectra are from populations with identical theoretical spectra. The sampling distribution of SFT has been derived, allowing hence ERS/ERD to be evaluated under a statistical basis. An example of the technique was also provided in the EEG signals from 10 normal subjects during intermittent photic stimulation.

The authors examined central and cerebral hemodynamics in children during gynecological laparoscopic interventions. The course of 64 anesthesias was analyzed in girls aged 3 to 16 years, who had undergone laparoscopic surgery. Central hemodynamics was studied by tetrapolar rheography on a Diamant apparatus; cerebral oximetry was examined on a Critikon RedOx Monitor 2020 device. The findings demonstrate that pneumoperitoneum application causes immediate cardiovascular changes. Transfer of patients to Trendelenburg's position had a beneficial impact on central hemodynamics, by facilitating the normalization of venous return, thus maintaining cardiac output. Central hemodynamic disorders promptly affected cerebral blood volume and oxygen status. After pneumoperitoneum application, there was an average of 3% reduction in regional cerebral tissue saturation.

The investigation evaluated the effect of various volatile anesthetics on cerebral blood volume and oxygen status in sick children at the stage of anesthesia induction. Ninety-two children were distributed into 3 groups: Groups 1 (n = 36) and 2 (n = 24) underwent stepwise induction with halothane and enflurane, respectively. Group 3 (n = 32) had vital capacity rapid inhalation induction with sevoflurane. Cerebral oximetry (NIRS method) was used to measure the content of hydroxyhemoglobin, deoxyhemoglobin, the total level of hemoglobin and to assess regional cerebral tissue saturation (rSO2). Halothane was ascertained to increase cerebral blood volume by 20.5% whereas enflurane and sevoflurane increased it only by 8.8 and 9.0%, respectively. In all cases, the value of rSO2 remained comparatively high, by exceeding the baseline level by 3-5%.

Due to the multidisciplinary character of psychophysiology, the problem of comparability of psychological and physiological phenomena of different natures and levels of organization has always been raised. This requires the interaction of theory and methodology to appropriately address the specifics of the psychophysiological paradigm, all the while maintaining their grounding in the actual psychological and physiological concepts. The history of EEG studies of mental activity shows that a weak theoretical basis at certain stages can result not only in methodological crises but can also affect empirical data collection and interpretation. An adequate theory can lend strong support to the methodology with "brain-oriented" structuring of psychological tasks and such a theory improves the neurophysiological informative value of the EEG parameters referring to the psychological characteristics of mental processes etc. On the other hand, the great importance of the EEG recording and processing techniques can result in overrating technological progress, hence frequently holding back meaningful interpretation and construction of a comprehensive psychophysiological conceptual framework. This in turn causes demands for higher material and intellectual outlays, due to overspecialization in research, and results in work duplication as well as the creation of a fragmentary knowledge structure. This article illustrates how the multidisciplinary interaction of theory and methodology, when focused on theoretical problems, can yield a series of concepts with escalating levels of integration, bringing together such different branches of psychophysiology as the study of functional states and of individual differences. As a result, this extends the theoretical model based on normal material to encompass borderline constitutional psychopathology.

Intermittent photic stimulation (IPS) is an important functional test, which can induce the photic driving in the electroencephalogram (EEG). It is capable of enhancing latent oscillations manifestations not present in the resting EEG. However, for adequate quantitative evaluation of the photic driving, these changes should be assessed on a statistical basis. With this aim, the sampling distribution of spectral F test was investigated. On this basis, confidence limits of the SFT-estimate could be obtained for different practical situations, in which the signal-to-noise ratio and the number of epochs used in the estimation may vary. The technique was applied to the EEG of 10 normal subjects during IPS, and allowed detecting responses not only at the fundamental IPS frequency but also at higher harmonics. It also permitted to assess the strength of the photic driving responses and to compare them in different derivations and in different subjects.

The problems of hypothermia in the perioperative period, which are one of the most important ones in pediatric practice, in babies in particular, are solved, by using a broad spectrum of methods for preventing and correcting the patients' thermal balance. Convection heating systems exercise an on-line control over the baby's thermal regime during a surgical intervention and intensive care. The authors' own experience allows these systems to be recommended for wide practical application in the activities of anesthesiology and intensive care services.

The electroencephalogram amplitude spectra at 11 fixed frequencies of intermittent photic stimulation of 3 to 24 Hz were combined into driving "profiles" for 14 scalp points in 8 male and 7 female normal subjects aged 9 to 17 years. The driving response varied over frequency and was detected in 70 to 100% of cases in the occipital areas (maximum) and in 27 to 77% of cases in the frontal areas (minimum) using as a criterion peak amplitude 20% higher than those of the neighbors. Each subject responded, on average, to 9.7 +/- 1.15 intermittent photic stimulation frequencies in the right occipital area and to 6.8 +/- 1.97 frequencies in the right frontal area. Most of the driving responses (in relation to the previous background) were significant according to the spectral F-test (alpha = 0.05), which also detected changes in some cases of low amplitude responses not revealed by the peak criterion. The profiles had two maxima in the alpha and theta bands in all leads. The latter was not present in the background spectra in the posterior areas and was less pronounced in the anterior ones. The weight of the profile theta maximum increased towards the frontal areas where the two maxima were similar, while the profile amplitudes decreased. The profiles repeated the shape of the background spectra, except for the theta band. The interhemispheric correlation between profiles was high. The theta driving detected in all areas recorded suggests a generalized influence of the theta generators in prepubertal and pubertal subjects.

The efficiency of nutritive therapy was analyzed in cases of 37 patients with gastrointestinal pathologies. Group 1 comprised 12 patients with fistulas of different etiologies and localizations; and group 2 comprised 15 patients with esophageal pathologies, including 7 children with esophageal atresia and 8 children with post-burn cicatricial stenosis of the esophagus. A method of nutrition-status correction by means of both enteral and parenteral feeding is suggested on the basis of examination findings comprising both clinical and laboratory-and-instrumental data. Preparations for parenteral feeding, i.e. 10-20% fatty emulsions, 10% amino acids solutions and 15-20% glucose solutions, were made use of. Enteral diets: semi-element oligopeptide solutions, like Nutrilon pepti TSC, Alphare. Balanced mixtures: sour-milk Nan, AL 110, Nutrizon, Nutridrink. Practical recommendations were defined, on the basis of study results, as to the therapeutic feeding schemes during the in-hospital treatment stages.

Forty-seven children, aged 2 to 12, with different pathologies, who underwent the abdominal aortography with the bolus introduction of 60% verografin, i.e. a radiopaque contrast agent (RCA), 2-3 ml/kg for 2-3 sec. The osmolar index of blood went up sharply, diuresis increased 7-fold and the aldosterone content topped 2-fold the original level. Simultaneously, the plasma concentration of ketamine was reducing by 2 times faster than in children who were not administered RCA. An additional introduction of an anesthetic made on minute 3 after RCA injection was suggested to modify the anesthesia management scheme.

Bio-impedancemetry, based on the ability of tissues to carry electric current, was used to evaluate the water balance in the bodies of children at laparoscopic surgical interventions. The clinical cause of 67 anesthesias in children, aged 5 to 14, operated by using the laparoscopic technique was analyzed. It was established, through assessing a combination of changes in the studied indices, that the application of the pneumoperitoneum is the most significant factor in the pathogenesis of occurring changes. The stage in question was accompanied by maximal changes in the studied parameters: an increase in the body impedance, a decrease in the limb impedance, reduced cardiac discharge and stroke volume, a reduced cardiac beat rate (CBR) and a high arterial pressure (AP). The position of a patient on the surgical plate was another important factor affecting the changes in the studied parameters. After a prolonged stay in Fovler's position led to an outflow of fluid from the lower limbs in children, which was confirmed by a limb reduced impedance. After the horizontal position was recovered, the impedance went up.

In order to identify latent bioelectrical oscillators, 15 normal subjects (aged 9-17 years, 8 males, 7 females) were subjected to intermittent photic stimulation. The EEG amplitude spectra corresponding to the 11 fixed frequencies of stimulation presented (3-24 Hz) were combined to form "profiles" of the driving reaction in the right occipital area. The driving response varied with frequency, and was demonstrable in 70-100% of cases (using as criterion peak amplitudes 20% larger than those of the neighbors). The strongest responses were observed at the frequency closest to the alpha peak of the resting EEG. A secondary profile maximum was in the theta band. In 10 subjects, this maximum exceeded half the alpha peak (with an average of 72.4% of the alpha peak), while in the resting spectra, theta amplitudes were much lower than the alpha maxima. This responsiveness in theta activity seems to be characteristic of prepubertal and pubertal subjects. The profiles and resting EEG spectra showed a highly significant Pearson's correlation, with the peak in the theta band of the profiles being the main difference observed between them. The correlation coefficient was significantly correlated with the ratio of the maxima in the theta and alpha bands (R = -0.77, P<0.001). The correlation coefficient between profile and resting spectrum may be a useful indicator in screening methods used to reveal latent cerebral oscillators. Profiles for the second and third harmonics were correlated with those of the first harmonic (fundamental frequency), when considering the corresponding EEG frequencies. Peak frequencies in all three profiles were close to those of the individual's background alpha rhythm, and peak amplitudes in higher harmonics were not much lower than those of the fundamental frequency (mean values of 84 and 63%, for second and third harmonics, respectively).

There were studied 14 children (mean age 5.71 +/- 0.60 years, body weight 18.95 +/- 3.50 kg, height 101.0 +/- 4.03 cm) with initially normal osmotic and volumic status. Plasma osmolarity, blood aldosterone level, aqueous compartments balance were (evaluated by segmented bioimpedance spectrometry), urine osmolarity and diuresis were investigated after bolus injection of x-ray contrast agent (RCA) urografin-60% (mean volume 2 ml/kg for 2-4 sec). A statistically significant gradual decrease in the total volume of water (TVW) in the organism was observed, with 8.53% deficiency of TVW by the second hour after RCA injection in comparison with the initial level. TVW deficiency developed as the result of diuresis which increased 7-fold in the presence of increased plasma osmolarity after injection of RCA bolus. Correction of the volume of circulating blood and plasma was carried out mainly at the expense of intracellular liquid, whose deficiency was actually 4.5 times higher than of extracellular liquid. Bioimpedance spectrometry indicated centralized redistribution of water in the organism, as TVW deficiency was mainly due to water in the limbs. The results indicate the need in infusion therapy after RCA injection in order to correct the resultant water deficit.

The study was carried out on 13 children (2-12 years) subjected to abdominal aortography. The children were divided into 2 groups. Changes in plasma concentrations of ketamine and its metabolism were evaluated during anesthesia after bolus injection of ionic highly osmolar and nonionic low-osmolar x-ray contrast agents (RCA). Injection of an RCA bolus was associated with a 2-fold more rapid drop of the anesthetic concentration in the blood, increase of renal clearance of ketamine and its metabolites; the osmotic effect of ionic highly osmolar and nonionic low-osmolar RCA on ketamine pharmacokinetics virtually did not differ.

Near infrared spectroscopy (NIRS) was used for noninvasive measurement of oxyhemoglobin (O2Hb) and total hemoglobin (tHb) in cerebral tissue and for evaluating local hemoglobin saturation with oxygen (rSO2) and cytochrome oxidase (Cytaa3) redox status in 68 children (6-14 years) during intravenous induction anesthesia with various anesthetics. Monoanesthesia with ketamine essentially increased the level of tHb and rSO2 and decreased the oxidized Cytaa3 fraction. Combined induction with ketamine and midazolame and propofol induction did not cause notable changes in the values of cerebral oxymetry.

A new method, spectroscopy in a spectrum approximating the infrared, was used in children during total anesthesia for evaluating the oxygen status and blood content of the brain. This method shows in the real time mode the content of total hemoglobin and its fractions oxyhemoglobin and deoxyhemoglobin in brain tissue. Oxidative (RedOx) status of cerebral cell cytochrome oxidase was assessed. A total of 128 children aged 7 months to 14 years were observed throughout total anesthesia. The method is highly informative and can be used for monitoring the degree of oxygenation, tissue respiration, and blood filling of the brain during total anaesthesia in children and for evaluating the effects of various anesthetics on these parameters.

Background: Various methods of detecting cancer with fluorescence have been developed. One type of fluorescence is based on the tumor-localizing properties of certain dyes. However, the phototoxicity of most known tumor-localizing dyes hinders the safe use of such diagnostic methods. The authors have developed a fluorescence imaging system to detect the distribution of a nontoxic dye, fluorescein, and they have evaluated the feasibility of the system by using it to detect oral dysplastic lesions in hamsters., Methods: Dysplasia was induced in the cheek pouches of hamsters by application of the carcinogen 9,10-dimethyl-1,2-benzantracene. Fluorescein was administered to the hamsters either intravenously or orally before the fluorescence examination. The endoscopic fluorescence system produced dye-distribution images of both treated and control pouches. Two fluorescence images in different spectral regions were processed for each dye image. Biopsy material from both pouches was examined histopathologically., Results: The accumulation of fluorescein was detected in 22 of 23 specimens containing dysplastic lesions., Conclusions: These results demonstrate the utility of this fluorescein accumulation method in the detection of dysplasia. The accumulation of fluorescein in dysplastic lesions may point to acidification of interstitial medium in such lesions.

On the basis of 1800 examinations of tumor cells the authors show possibility for accumulation of luminescent dye uranine by malignant cells. The conception of the mechanism of its accumulation, confirmed by the studies of reinoculated tumors of rats (60 examinations) is presented. Of 821 patients with ulcers of the stomach 641 had no luminescence; at repeated examination cancer and ulcer were revealed in 7 of them. Malignant transformation was verified by histologic method in 102 of 180 patients with luminescent ulcers. In 22 patients intestinal metaplasia was detected in the luminescence areas and in 40--there was a rough epitnelial dysplasia. At the examination of these patients two years later, cancer of the stomach at the sites of previously revealed luminescence was detected in 15 patients (26.3%).

In 67 borderline psychiatric patients suffering from schizotypal/slowly developing schizophrenic disorders and 18 patients suffering from cyclothymia, the factor structure of the period (interval-amplitude) parameters of the EEG proved to be similar to that obtained in normal subjects during mental activity and reported in part I (Lazarev, Int. J. Psychophysiol., 28 (1998) 77-98). However, 51 patients with schizotypal disorders with a predominance of asthenic-like symptomatology, characterized by mild thought disorders with difficulty in focusing attention, were distinguished from normal subjects, cyclothymic patients and other patients of schizotypy without well-defined asthenic symptoms by significantly increased values of EEG Factor II which was positively related to the index-presence in epoch, frequency and regularity of low-amplitude beta-waves, and reduced values of an EEG Factor III which was positively correlated with mean alpha-period and theta-index. According to normative data (part I; Lazarev, Int. J. Psychophysiol., 28 (1998) 77-98), this probably reflects a neurodynamic imbalance between an excess of 'cortical excitation' (Factor II) and a deficit of 'active selective inhibition' (Factor III). This imbalance appears to be opposite to the changes in values of these factors found in normal subjects during focusing attention and motor automation, when compared with relaxed wakefulness. The functional properties of Factors II and III ascribed on the basis of psychological testing suggest that such an imbalance could reflect a predominance of successively organised associative mental processes over the selective inhibition of irrelevant associations. This could cause difficulties in voluntary attention, mental automation and in the performance of simultaneous mental operations. In most cases, there was no difference in Factor I which was positively related to the index, amplitude and regularity of alpha-activity and wave amplitudes in other bands, and negatively related to the indices and mean periods of delta- and theta-waves, the factor presumed to depict 'general activation'.

The potentialities of cerebral oximetry in the para-infrared band as a means of neuromonitoring are assessed. The method is highly informative for selecting the treatment strategy during the acute period of craniocerebral injury and cerebrovascular diseases. Simultaneous analysis of intracranial pressure, central hemodynamics, and cerebral oximetry permits differentiation of mechanisms of intracranial hypertension and its compensation. Increase of rSO2 in increased intracranial pressure corresponds to brain hyperemia, its decrease to cerebral ischemia. A long trend of rSO2 changes is informative for disease prediction.

In 95 normal subjects, a separate evaluation of the amplitude and frequency parameters of EEG by period analysis made it possible to reveal, using factor analysis, four independent groups of parameters--the EEG factors, two of which being independent of the amplitude fluctuations. They were considered as integral EEG characteristics of qualitatively different neurophysiological processes. Decrease of Factor I values during mental activity (called 'general activation') reflected an intercorrelated desynchronization of the wave amplitudes in all the bands, a decrease of alpha-index (percentage presence in epoch) and regularity together with parallel increase of the indices and mean periods of delta- and theta-waves. This generalized reaction has shown 'non-specific' dependence upon novelty and difficulty of the tasks and stimuli with certain task-specific topographical distribution. An increase of values of regional Factor Ia in the anterior areas was caused by delta- and theta-amplitude synchronization, more pronounced during matching the rhymes (MR) than in mental multiplication (MM). An increase of Factor II values (related to increase of the index, frequency and regularity of beta-activity and called 'cortical excitation', CE) was more expressed during MR, whereas an increase of Factor III values (an increase of mean alpha-period and theta-index called 'active selective inhibition', ASI) was characteristic of MM, the latter reaction being evident in the right hemisphere. During analysis of external sound stimuli and rhythmical clenching of a fist, an increase of Factor III values was accompanied by decrease of Factor II values [corrected]; in the motor activity, such reciprocal reaction being localized in the central areas contralateral to the hand moved . Neuropsychological analysis suggests that CE correlates with associative and successively organized mental operations involving search for memory traces and ASI presumably relates to different aspects of mental selectivity such as simultaneous mental operations, voluntary attention and mental automation, the latter two cases being supported by parallel reduction of CE.

Diprivan was a component of anesthesia for angiographic studies and x-ray endovascular treatment in 30 patients aged 4 months to 16 years. Patients with diseases of the head and neck (hemangiomas and arteriovenous dysplasias), thoracic and abdominal cavities and kidneys (portal hypertension, pancreatic cysts, developmental defects, renal injuries, etc.), and limbs (angiodysplasias, traumatic injuries to the vessels, developmental defects of the vessels, etc.) were examined. Use of various methods of examination, including mathematical analysis of cardiac rhythm, demonstrated the stability of anesthesia and negligible fluctuations in the principal hemodynamic parameters. Hence, diprivan is an effective and perspective agent which may be included in anesthesiological protocols for children undergoing angiographic diagnosis and x-ray endovascular treatment.

It is shown that Ultravist makes it possible to receive clear visualization of vessel channel in the zone "of interest" without changing functional conditions of heart vascular system and biochemical blood parameters (level of erythrocytes, bilirubine, urine nitrogen, activity of aspartataminotransferase). In concentration 30 mg/ml in vitro and in vivo Ultravist decreases a viscosity limit not affecting other rheological properties of blood. A mechanism of the found Ultravist effect and prospects of its application in practice for children are considered.