Neurologic deterioration in sinking skin flap syndrome after diuretic therapy

2020 ◽  
pp. 10.1212/CPJ.0000000000000859
Author(s):  
Cristina Boccagni ◽  
Sergio Bagnato ◽  
Valerio Alaimo ◽  
Giuseppe Galardi
Keyword(s):  
Regional Blood Flow ◽  
Pathological Condition ◽  
Skin Flap ◽  
Diuretic Therapy ◽  
Epileptic Seizures ◽  
Chronic Fatigue ◽  
Motor Deficits ◽  
Large Bone ◽  
The Brain ◽  
Large Bone Defects

The sinking skin flap syndrome (SSFS), or syndrome of the trephined, is a pathological condition arising from the presence of large bone defects of the skull. Originally described by Grant and Norcross in patients with a skin flap depression following craniectomy [1], SSFS has a multifaceted clinical presentation, including chronic fatigue, headache, dizziness, impaired vigilance, motor deficits, cognitive deficits, epileptic seizures, and visual symptoms [2]. SSFS pathophysiology is related to the atmospheric pressure exerted on the brain through the craniectomy, inducing brain compression, changes in the cerebrospinal fluid (CSF) dynamics, impaired venous return, and decrease in the regional blood flow, alone or in combination [2]. In this report we describe a case of SSFS complicated by paradoxical uncal herniation due to diuretic therapy.

Designing maxillofacial prosthesis for bone reconstruction: an overview

2022 ◽  
Vol 11 (2) ◽  
pp. 1-11
Author(s):  
Oumaima Laghzali ◽  
Gargi Shankar Nayak ◽  
Flavien Mouillard ◽  
Patrick Masson ◽  
Geneviève Pourroy ◽  
...  
Keyword(s):  
Large Area ◽  
Maxillofacial Region ◽  
Element Analysis ◽  
Maxillofacial Prosthesis ◽  
Temporomandibular Joints ◽  
The Finite Element Analysis ◽  
Masticatory System ◽  
Large Bone ◽  
The Brain ◽  
Large Bone Defects

A cranio-maxillofacial region contains several bones and serves to protect and support the area, from the brain to the masticatory system. In this paper the clinical and research aspects of craniomaxillofacial biomaterials have been highlighted to serve as a guide into the wide world of their reconstructions. After a quick look into the anatomy, the review focuses on the causes of large bone defects in this region, and how they influence the designing process of the implant. Since it is a large area to unfold, only the maxillary, the mandible and the temporomandibular joints are highlighted. Understanding the biomechanics of mandible and temporomandibular joints is quite important, as it strongly influences the choice of the biomaterial. Thus, the latest techniques implemented to understand the biomechanics of the mandible are also highlighted. Via the finite element analysis, a simulation can help to identify the forces and the movements of the mandible and to predict the possible outcome of the implantation influencing the choice of the biomaterial.

Complexity Measures of Brain Electrophysiological Activity

2010 ◽  
Vol 24 (2) ◽  
pp. 131-135 ◽  
Author(s):  
Włodzimierz Klonowski ◽  
Pawel Stepien ◽  
Robert Stepien
Keyword(s):  
Brain Activity ◽  
Deterministic Chaos ◽  
Epileptic Seizures ◽  
Eeg Signal ◽  
Eeg Signals ◽  
Complexity Measures ◽  
Electrophysiological Activity ◽  
Signal Complexity ◽  
Physiological Sleep ◽  
The Brain

Over 20 years ago, Watt and Hameroff (1987 ) suggested that consciousness may be described as a manifestation of deterministic chaos in the brain/mind. To analyze EEG-signal complexity, we used Higuchi’s fractal dimension in time domain and symbolic analysis methods. Our results of analysis of EEG-signals under anesthesia, during physiological sleep, and during epileptic seizures lead to a conclusion similar to that of Watt and Hameroff: Brain activity, measured by complexity of the EEG-signal, diminishes (becomes less chaotic) when consciousness is being “switched off”. So, consciousness may be described as a manifestation of deterministic chaos in the brain/mind.

Basic Ideas and Principles for Quantifying Regional Blood Flow with Nuclear Medical Techniques

1996 ◽  
Vol 35 (05) ◽  
pp. 181-185 ◽  
Author(s):  
H. Herzog
Keyword(s):  
Blood Flow ◽  
Nuclear Medicine ◽  
Regional Blood Flow ◽  
Visual Presentation ◽  
Regional Cerebral Blood ◽  
Basic Principles ◽  
Parametric Images ◽  
Major Application ◽  
Basic Ideas ◽  
The Brain

SummaryThe measurement of blood flow in various organs and its visual presentation in parametric images is a major application in nuclear medicine. The purpose of this paper is to summarize the most important nuclear medicine procedures used to quantify regional blood flow. Starting with the first concepts introduced by Fick and later by Kety-Schmidt the basic principles of measuring global and regional cerebral blood are discussed and their relationships are explained. Different applications and modifications realized first in PET- and later in SPECT-studies of the brain and other organs are described. The permeability and the extraction of the different radiopharmaceuticals are considered. Finally some important instrumental implications are compared.

Automated System for Epileptic Seizures Prediction based on Multi-Channel Recordings of Electrical Brain Activity

2018 ◽  
pp. 115-122 ◽  
Author(s):  
V. A. Maksimenko ◽  
A. A. Harchenko ◽  
A. Lüttjohann
Keyword(s):  
Epileptic Seizure ◽  
Brain Activity ◽  
Epileptic Seizures ◽  
Automated System ◽  
Brain Computer Interfaces ◽  
Electrical Brain Activity ◽  
Computer Interfaces ◽  
Prediction And Prevention ◽  
The Brain

Introduction: Now the great interest in studying the brain activity based on detection of oscillatory patterns on the recorded data of electrical neuronal activity (electroencephalograms) is associated with the possibility of developing brain-computer interfaces. Braincomputer interfaces are based on the real-time detection of characteristic patterns on electroencephalograms and their transformation  into commands for controlling external devices. One of the important areas of the brain-computer interfaces application is the control of the pathological activity of the brain. This is in demand for epilepsy patients, who do not respond to drug treatment.Purpose: A technique for detecting the characteristic patterns of neural activity preceding the occurrence of epileptic seizures.Results:Using multi-channel electroencephalograms, we consider the dynamics of thalamo-cortical brain network, preceded the occurrence of an epileptic seizure. We have developed technique which allows to predict the occurrence of an epileptic seizure. The technique has been implemented in a brain-computer interface, which has been tested in-vivo on the animal model of absence epilepsy.Practical relevance:The results of our study demonstrate the possibility of epileptic seizures prediction based on multichannel electroencephalograms. The obtained results can be used in the development of neurointerfaces for the prediction and prevention of seizures of various types of epilepsy in humans. 

scholarly journals Factors related to large bone defects of bipolar lesions and a high number of instability episodes with anterior glenohumeral instability

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Noboru Matsumura ◽  
Kazuya Kaneda ◽  
Satoshi Oki ◽  
Hiroo Kimura ◽  
Taku Suzuki ◽  
...  
Keyword(s):  
Humeral Head ◽  
Glenohumeral Joint ◽  
Three Dimensional ◽  
Clinical Results ◽  
Bone Defects ◽  
Symptom Duration ◽  
Glenohumeral Instability ◽  
Explanatory Variables ◽  
Large Bone ◽  
Large Bone Defects

Abstract Background Significant bone defects are associated with poor clinical results after surgical stabilization in cases of glenohumeral instability. Although multiple factors are thought to adversely affect enlargement of bipolar bone loss and increased shoulder instability, these factors have not been sufficiently evaluated. The purpose of this study was to identify the factors related to greater bone defects and a higher number of instability episodes in patients with glenohumeral instability. Methods A total of 120 consecutive patients with symptomatic unilateral instability of the glenohumeral joint were retrospectively reviewed. Three-dimensional surface-rendered/registered models of bilateral glenoids and proximal humeri from computed tomography data were matched by software, and the volumes of bone defects identified in the glenoid and humeral head were assessed. After relationships between objective variables and explanatory variables were evaluated using bivariate analyses, factors related to large bone defects in the glenoid and humeral head and a high number of total instability episodes and self-irreducible dislocations greater than the respective 75th percentiles were evaluated using logistic regression analyses with significant variables on bivariate analyses. Results Larger humeral head defects (P < .001) and a higher number of total instability episodes (P = .032) were found to be factors related to large glenoid defects. On the other hand, male sex (P = .014), larger glenoid defects (P = .015), and larger number of self-irreducible dislocations (P = .027) were related to large humeral head bone defects. An increased number of total instability episodes was related to longer symptom duration (P = .001) and larger glenoid defects (P = .002), and an increased number of self-irreducible dislocations was related to larger humeral head defects (P = .007). Conclusions Whereas this study showed that bipolar lesions affect the amount of bone defects reciprocally, factors related to greater bone defects differed between the glenoid and the humeral head. Glenoid defects were related to the number of total instability episodes, whereas humeral head defects were related to the number of self-irreducible dislocations.

Neurospect Findings in Patients Exposed to Neurotoxic Chemicals

1994 ◽  
Vol 10 (4-5) ◽  
pp. 561-571
Author(s):  
Gunnar Heuser ◽  
Ismael Mena ◽  
Francisca Alamos
Keyword(s):  
Elderly Patients ◽  
Qualitative Analysis ◽  
Right Hemisphere ◽  
Young Patients ◽  
Chronic Fatigue ◽  
Psychiatric Symptomatology ◽  
Elderly Individuals ◽  
Parietal Lobes ◽  
The Right ◽  
The Brain

Exposures to neurotoxic chemicals such as pesticides, glues, solvents, etc. are known to induce neurologic and psychiatric symptomatology. We report on 41 patients 16 young patients (6 males, 10 females, age 34 8 yrs.) and 25 elderly patients (9 males, 16 females, age 55 7 yrs). Fifteen of them were exposed to pesticides, and 29 to solvents. They were studied with quantitative and qualitative analysis of regional cerebral bood flow (rCBF), performed with 30 mCi of Xe-133 by inhalation, followed by 30 mCi of Tc-HMPAO given intravenously. Imaging was performed with a brain dedicated system, distribution of rCBF was assessed with automatic ROI definition, and HMPAO was normalized to maximal pixel activity in the brain. Results of Xe rCBF are expressed as mean and S.D. in ml/min/100g, and HMPAO as mean and S.D. uptake per ROI, and compared with age-matched controls 10 young and 20 elderly individuals. Neurotoxics HMPAO Uptake Young Elderly R. Orbital frontal R. Dorsal frontal .70 .66 p < 0.05 R. Temporal .64 p < 0.001 R. Parietal .66 .66 We conclude that patients exposed to chemicals present with diminished CBF, worse in the right hemisphere, with random presentation of areas of hypoperfusion, more prevalent in the dorsal frontal and parietal lobes. These findings are significantly different from observations in patients with chronic fatigue and depression, suggesting primary cortical effect, possibly due to a vasculitis process.

Regional blood flow in the brain and spinal cord of hypothermic rats

1989 ◽  
Vol 257 (3) ◽  
pp. H785-H790
Author(s):  
T. Sakamoto ◽  
W. W. Monafo
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Brain Stem ◽  
Regional Blood Flow ◽  
Experimental Conditions ◽  
Pentobarbital Sodium ◽  
Arterial Blood ◽  
Group A ◽  
Group B ◽  
The Brain

[14C]butanol tissue uptake was used to measure simultaneously regional blood flow in three regions of the brain (cerebral and cerebellar hemispheres and brain stem) and in five levels of the spinal cord in 10 normothermic rats (group A) and in 10 rats in which rectal temperature had been lowered to 27.7 +/- 0.3 degrees C by applying ice to the torso (group B). Pentobarbital sodium anesthesia was used. Mean arterial blood pressure varied minimally between groups as did arterial pH, PO2, and PCO2. In group A, regional spinal cord blood flow (rSCBF) varied from 49.7 +/- 1.6 to 62.6 +/- 2.1 ml.min-1.100 g-1; in brain, regional blood flow (rBBF) averaged 74.4 +/- 2.3 ml.min-1.100 g-1 in the whole brain and was highest in the brain stem. rSCBF in group B was elevated in all levels of the cord by 21-34% (P less than 0.05). rBBF, however, was lowered by 21% in the cerebral hemispheres (P less than 0.001) and by 14% in the brain as a whole (P less than 0.05). The changes in calculated vascular resistance tended to be inversely related to blood flow in all tissues. We conclude that rBBF is depressed in acutely hypothermic pentobarbital sodium-anesthetized rats, as has been noted before, but that rSCBF rises under these experimental conditions. The elevation of rSCBF in hypothermic rats confirms our previous observations.

scholarly journals Bedside examination of the vestibular and ocular motor system in patients with acute vertigo or dizziness

2019 ◽  
Vol 3 (2) ◽  
pp. 2514183X1988615
Author(s):  
Alexander A Tarnutzer ◽  
Marianne Dieterich
Keyword(s):  
Diagnostic Testing ◽  
Initial Assessment ◽  
Head Impulse Test ◽  
Motor Deficits ◽  
Ocular Motor ◽  
Bedside Examination ◽  
Life Threatening ◽  
Ocular Motor System ◽  
Bedside Tests ◽  
The Brain

In the initial assessment of the patient with acute vertigo or dizziness, both structured history-taking and a targeted bedside neuro-otological examination are essential for distinguishing potentially life-threatening central vestibular causes from those of benign, self-limited peripheral labyrinthine origin and thus for deciding on further diagnostic testing. In this article, the key elements of the vestibular and ocular motor examination, which should be obtained at the bedside in these acutely dizzy patients, will be discussed. Specifically, this will include the following five domains: ocular stability for (I) nystagmus and for (II) eye position (skew deviation), (III) the head-impulse test (HIT), (IV) postural stability, and (V) ocular motor deficits of saccades, smooth pursuit eye movements, and optokinetic nystagmus. We will also discuss the diagnostic accuracy of specific combinations of these bedside tests (i.e. HIT, testing for nystagmus and vertical divergence, referred to as the H.I.N.T.S. three-step examination), emphasizing that the targeted neuro-otological bedside examination is more sensitive for identifying central causes in acute prolonged vertigo and dizziness than early MRI of the brain.

scholarly journals Vascularization of Nanohydroxyapatite/Collagen/Poly(L-lactic acid) Composites by Implanting Intramuscularly In Vivo

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Hai Wang ◽  
Xiao Chang ◽  
Guixing Qiu ◽  
Fuzhai Cui ◽  
Xisheng Weng ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Orthopaedic Surgery ◽  
Bone Substitutes ◽  
Bone Defects ◽  
Large Defect ◽  
Natural Bone ◽  
Composition And Structure ◽  
Large Bone ◽  
Large Bone Defects

It still remains a major challenge to repair large bone defects in the orthopaedic surgery. In previous studies, a nanohydroxyapatite/collagen/poly(L-lactic acid) (nHAC/PLA) composite, similar to natural bone in both composition and structure, has been prepared. It could repair small sized bone defects, but they were restricted to repair a large defect due to the lack of oxygen and nutrition supply for cell survival without vascularization. The aim of the present study was to investigate whether nHAC/PLA composites could be vascularized in vivo. Composites were implanted intramuscularly in the groins of rabbits for 2, 6, or 10 weeks (n=5×3). After removing, the macroscopic results showed that there were lots of rich blood supply tissues embracing the composites, and the volumes of tissue were increasing as time goes on. In microscopic views, blood vessels and vascular sprouts could be observed, and microvessel density (MVD) of the composites trended to increase over time. It suggested that nHAC/PLA composites could be well vascularized by implanting in vivo. In the future, it would be possible to generate vascular pedicle bone substitutes with nHAC/PLA composites for grafting.

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