826: ASSESSMENT OF CEREBRAL AUTOREGULATION USING INVASIVE AND NONINVASIVE METHODS OF ICP MONITORING

Among possible causes of visual impairment or headache experienced by astronauts in microgravity or postflight and that hamper their performance, elevated intracranial pressure (ICP) has been invoked but never measured for lack of noninvasive methods. The goal of this work was to test two noninvasive methods of ICP monitoring using in-ear detectors of ICP-dependent auditory responses, acoustic and electric, in acute microgravity afforded by parabolic flights. The devices detecting these responses were handheld tablets routinely used in otolaryngology for hearing diagnosis, which were customized for ICP extraction and serviceable by unskilled operators. These methods had been previously validated against invasive ICP measurements in neurosurgery patients. The two methods concurred in their estimation of ICP changes with microgravity, i.e., 11.0 ± 7.7 mmHg for the acoustic method ( n = 7 subjects with valid results out of 30, auditory responses being masked by excessive in-flight noise in 23 subjects) and 11.3 ± 10.6 mmHg for the electric method ( n = 10 subjects with valid results out of 10 tested despite the in-flight noise). These results agree with recent publications using invasive access to cerebrospinal fluid in parabolic flights and suggest that acute microgravity has a moderate average effect on ICP, similar to body tilt from upright to supine, yet with some subjects undergoing large effects whereas others seem immune. The electric in-ear method would be suitable for ICP monitoring in circumstances and with subjects such that invasive measurements are excluded. NEW & NOTEWORTHY In-ear detectors of intracranial pressure-dependent auditory responses allow intracranial pressure to be monitored noninvasively during acute microgravity. The average pressure increase during 20-s long sessions in microgravity is 11 mmHg, comparable with an effect of body tilt. However, intersubject variability is large, with subjects who repeatedly experience from nothing to twice the average effect. A systematic in-flight use would allow the relationship between space adaptation syndrome and ICP to be established or dismissed.

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Cleavage of Human Embryos: Options and Diversity

Acta Naturae ◽

10.32607/20758251-2016-8-3-88-96 ◽

2016 ◽

Vol 8 (3) ◽

pp. 88-96

Author(s):

Yu. K. Doronin ◽

I. V. Senechkin ◽

L. V. Hilkevich ◽

M. A. Kurcer

Keyword(s):

Time Lapse ◽

Reproductive Technologies ◽

Human Embryos ◽

Imaging Data ◽

Noninvasive Methods ◽

Topographic Features ◽

Time Parameters ◽

Embryo Cleavage ◽

Time Lapse Imaging ◽

Developmental Dynamics

In order to estimate the diversity of embryo cleavage relatives to embryo progress (blastocyst formation), time-lapse imaging data of preimplantation human embryo development were used. This retrospective study is focused on the topographic features and time parameters of the cleavages, with particular emphasis on the lengths of cleavage cycles and the genealogy of blastomeres in 2- to 8-cell human embryos. We have found that all 4-cell human embryos have four developmental variants that are based on the sequence of appearance and orientation of cleavage planes during embryo cleavage from 2 to 4 blastomeres. Each variant of cleavage shows a strong correlation with further developmental dynamics of the embryos (different cleavage cycle characteristics as well as lengths of blastomere cycles). An analysis of the sequence of human blastomere divisions allowed us to postulate that the effects of zygotic determinants are eliminated as a result of cleavage, and that, thereafter, blastomeres acquire the ability of own syntheses, regulation, polarization, formation of functional contacts, and, finally, of specific differentiation. This data on the early development of human embryos obtained using noninvasive methods complements and extend our understanding of the embryogenesis of eutherian mammals and may be applied in the practice of reproductive technologies.

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Complex use of noninvasive methods for estimating microcirculation of the blood and oxidative metabolism on the big sting finger in patients with diabetes, such as permeable diagnostic diagnostics diagnostics, patients with diable diagnosis

Endocrine Abstracts ◽

10.1530/endoabs.63.p606 ◽

2019 ◽

Author(s):

Michael Shinkin Mikhail ◽

Mktrumyan Ashot ◽

Zvenigorodskaya Larisa

Keyword(s):

Oxidative Metabolism ◽

Noninvasive Methods ◽

Patients With Diabetes

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A review of the methods to assess cerebral autoregulation

Human Health and Medical Engineering ◽

10.2495/hhme130121 ◽

2014 ◽

Author(s):

Cun-Ling Lv ◽

Ying-Qi Xing ◽

Zhen-Ni Guo ◽

Yi Yang

Keyword(s):

Cerebral Autoregulation

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Multimodal Monitoring of Cerebral Autoregulation After Pediatric Brain Injury

Case Medical Research ◽

10.31525/ct1-nct04242602 ◽

2020 ◽

Author(s):

Keyword(s):

Brain Injury ◽

Cerebral Autoregulation ◽

Multimodal Monitoring ◽

Pediatric Brain Injury ◽

Pediatric Brain

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Preoperative MRI findings and prediction of diagnostic utility of foramen ovale electrodes

Journal of Neurosurgery ◽

10.3171/2018.12.jns182093 ◽

2020 ◽

Vol 132 (3) ◽

pp. 692-699 ◽

Cited By ~ 1

Author(s):

Sarah K. Bick ◽

Marjan S. Dolatshahi ◽

Benjamin L. Grannan ◽

Andrew J. Cole ◽

Daniel B. Hoch ◽

...

Keyword(s):

Minimally Invasive ◽

Treatment Decision ◽

Temporal Lobectomy ◽

Categorical Variables ◽

Continuous Variables ◽

Foramen Ovale ◽

Mri Findings ◽

Noninvasive Methods ◽

Diagnostic Modality ◽

Diagnostic Investigations

OBJECTIVEForamen ovale electrodes (FOEs) are a minimally invasive method to localize mesial temporal seizures in cases in which noninvasive methods are inconclusive. The objective of this study was to identify factors predicting the ability of FOEs to yield a diagnosis in order to determine optimal candidates for this procedure.METHODSAll cases of diagnostic investigations performed with FOEs at the authors’ institution between 2005 and 2017 were reviewed. FOE investigation was defined as diagnostic if it led to a treatment decision. Demographic and clinical variables for diagnostic and nondiagnostic investigations were compared using a Wilcoxon rank-sum test for continuous variables and Fisher’s exact test for categorical variables.RESULTSNinety-three patients underwent investigations performed with FOEs during the study period and were included in the study. FOE investigation was diagnostic in 75.3% of cases. Of patients who underwent anterior temporal lobectomy following diagnostic FOE evaluation, 75.9% were Engel class I at last follow-up (average 40.1 months). When the diagnostic and nondiagnostic FOE groups were compared, patients who had diagnostic investigations were more likely to be male (57.1% male vs 26.1% in the nondiagnostic group, p = 0.015). They were also more likely to have temporal lesions on preoperative MRI (p = 0.018).CONCLUSIONSFOEs are a useful, minimally invasive diagnostic modality resulting in a treatment decision in 75% of cases. Male patients and patients with temporal lesions on MRI may be most likely to benefit from FOE investigation.

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