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Momani Lina L Department of Electrical Engineering and Electronics, University of Liverpool, Brownlow Hill, Liverpool, L69 3GJ, UK. - - 2008
Hydrocephalus is a neurological disease that manifests itself in an elevated fluid pressure within the brain, and if left untreated, may be fatal. It is currently treated using shunt implants, which consist of a mechanical valve and tubes that regulate the pressure of cerebrospinal fluid (CSF) by draining excess fluid ...
Ufnal Marcin - - 2008
Recently, it was found that hydrogen sulfide (H2S) may serve as an important transmitter in peripheral organs as well as in the brain. The aim of the present study was to evaluate the possible function of H2S in the brain regulation of the circulatory system. Experiments were performed on conscious, ...
Lavinio A A Addenbrooke's Hospital, Academic Neurosurgery, Cambridge, UK. - - 2008
The pathophysiology of hydrocephalus can be modelled and described in terms of altered biomechanical parameters. Shunting is aimed to correct the patient's cerebrospinal fluid dynamics, compensating for inadequate cerebrospinal fluid re-absorption or insufficient volume buffering reserve. Computerized infusion studies implement intracranial pressure and arterial pressure signal processing and model analysis ...
Sahuquillo Juan - - 2008
OBJECTIVE: In the selection of a ventriculoperitoneal cerebrospinal fluid shunt, the intra-abdominal pressure (IAP) is traditionally neglected as a result of the idea that its value is close to 0 mmHg. Our aim was to explore the relationship between body mass index (BMI) and IAP with the goal of providing ...
Stahnisch Frank W - - 2008
François Magendie's (1783-1855) experimental model for measuring blood pressure in animals, which he developed in 1838, had a major impact on French physiology in the nineteenth century, especially upon Etienne-Jules Marey (1830-1904) in Paris. In due course it was also adopted by other European investigators, such as the Leipzig physiologist ...
Mase Mitsuhito - - 2008
BACKGROUND: The pathophysiology of idiopathic normal pressure hydrocephalus (I-NPH) is still unclear and the diagnosis is sometimes difficult. The aim of this study was to assess the biophysics of I-NPH by measuring intracranial compliance using cine MRI. METHODS: The study included patients with I-NPH (I-NPH group, n = 13), brain ...
Fujita Masaaki - - 2008
Reversible posterior leukoencephalopathy syndrome (RPLS) has been identified in several connective tissue diseases. However, there are no reports of RPLS associated with Takayasu arteritis (TA). We report the first case of TA associated with RPLS. A 23-year-old woman presented with sudden headache and vomiting, followed by generalized tonic-clonic seizures and ...
Pickard J D JD Academic Neurosurgery Division, University of Cambridge, P.O. Box 167, Addenbrookes Hospital, Cambridge CB20QQ, UK. - - 2008
Narrowing of the cranial dural venous sinuses has been implicated as contributing to elevated intracranial pressure in idiopathic intracranial hypertension [IIH]. Such narrowing may be either a fixed stenosis or secondary to raised ICP. We have investigated whether narrowing of the venous sinuses may reflect direct coupling between cerebrospinal fluid ...
Czosnyka Z Z Addenbrooke's Hospital, Academic Neurosurgery, Cambridge, UK. - - 2008
Since shunting is almost a purely mechanical treatment that radically affects pressure-volume compensation, patients' cerebrospinal fluid hydrodynamics compensation should be examined before a shunt is implanted. Apart from an opening pressure and a resistance to cerebrospinal fluid outflow, pulse amplitude of intracranial pressure and the content of vasogenic waves are ...
Williams Helen - - 2008
This hypothesis proposes that the difference in head size between the genders has a bearing on disease incidence. Smaller head size predisposes to spina bifida and larger head size predisposes to autism. In the fetus, the posterior fossa has a regulatory influence on maximum intracerebral cerebrospinal fluid (CSF) pressure. CSF ...
Czosnyka Z Z Academic Neurosurgical Unit, Addenbrooke's Hospital, Box 167, Cambridge CB2 0QQ, UK. - - 2008
There is increasing interest in evaluation of the pulse amplitude of intracranial pressure (AMP) in explaining dynamic aspects of hydrocephalus. We reviewed a large number of ICP recordings in a group of hydrocephalic patients to assess utility of AMP. From a database including approximately 2,100 cases of infusion studies (either ...
Dombrowski S M SM Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, OH 44195, USA. - - 2008
Chronic hydrocephalus (CH) is a neurological disease characterized by increased cerebrospinal fluid volume and pressure that is often associated with impaired cognitive function. By and large, CH is a complex and heterogeneous cerebrospinal fluid (CSF) disorder where the exact site of brain insult is uncertain. Several mechanisms including neural compression, ...
Riggo Julius De - - 2007
AIM: The goal of this study was to evaluate selected parameters of the Doppler curve of the pericallosal artery at children with hydrocephalus. METHODS: 12 patients with hydrocephalus were divided into two groups. Group 1 comprised children needing cerebrospinal fluid drainage, and group 2 comprised children without any indication for ...
Halaç Metin - - 2007
Spontaneous intracranial hypotension (SIH) is characterized by severe postural headache and low cerebrospinal fluid (CSF) pressure. Radionuclide cisternography (RC) is of some value in diagnosing CSF leakage causing SIH. However, the sensitivity of RC is too low to demonstrate the site of leakage. In these cases, the early appearance of ...
Bleier Benjamin S - - 2007
OBJECTIVES: To test the feasibility of laser tissue welding as a method of creating an endonasal tissue bond for the purpose of cerebrospinal fluid leak repair. STUDY DESIGN AND SETTING: An 808 nm diode laser was used with a 42% albumin solder to create laser welds in sheep nasal septal ...
Williams Helen - - 2008
Pressure in the central nervous system (CNS) depends upon the volume of tissue that it contains. This includes blood, cerebrospinal fluid (CSF), nerves and any space occupying lesions. The dependency of pressure on volume arises because the CNS is confined by bone. Venous and CSF pressure is linked to overall ...
Soler J M - - 2007
PURPOSE: We evaluated the effect of the alpha1-adrenergic agonist midodrine given orally for anejaculation in spinal cord injured men. MATERIALS AND METHODS: A total of 185 spinal cord injured patients who reported absent ejaculation during sexual intercourse and who failed to respond to penile vibratory stimulation were treated with midodrine ...
Heckmann Josef G - - 2007
OBJECT: The authors evaluated the characteristics of patients with idiopathic intracranial hypertension (IIH), and compared laser scanning tomography (LST) measurements of papilledema with the clinical parameters and cerebrospinal fluid (CSF) opening pressures obtained. METHODS: Twenty-four patients were included in this study; these individuals included 21 women and three men with ...
Sachse Kathleen T - - 2008
Caffeine, the most widely consumed psychoactive drug and a weak adenosine receptor antagonist, can be neuroprotective or neurotoxic depending on the experimental model or neurologic disorder. However, its contribution to pathophysiology and outcome in traumatic brain injury (TBI) in humans is undefined. We assessed serial cerebrospinal fluid (CSF) concentrations of ...
Miyati Tosiaki - - 2007
PURPOSE: To assess the state and dynamics of the intracranial system in idiopathic normal-pressure hydrocephalus (I-NPH), we determined intracranial compliance using magnetic resonance imaging (MRI). MATERIALS AND METHODS: The intracranial compliance index (ICCI), which was defined as the ratio of the peak-to-peak intracranial volume change (ICVC(p-p)) to the peak-to-peak cerebrospinal ...
Eklund Anders A Department of Biomedical Engineering and Informatics, Umeå University Hospital, 90185 Umeå, Sweden. - - 2007
The brain and the spinal cord are contained in a cavity and are surrounded by cerebrospinal fluid (CSF), which provides physical support for the brain and a cushion against external pressure. Hydrocephalus is a disease, associated with disturbances in the CSF dynamics, which can be surgically treated by inserting a ...
Traboulsi Raghida - - 2007
The cochlear aqueduct connecting intralabyrinthine and cerebrospinal fluids (CSF) acts as a low-pass filter that should be able to transmit infrasonic pressure waves from CSF to cochlea. Recent experiments have shown that otoacoustic emissions generated at 1kHz respond to pressure-related stapes impedance changes with a change in phase relative to ...
Vilela Marcelo Duarte - - 2008
BACKGROUND: Paradoxical herniation can occur as a complication of lumbar puncture in patients who had a decompressive craniectomy. The supposed mechanism is the development of a negative pressure gradient that allows the brain to shift toward the infratentorial space with subsequent herniation. Trendelenburg position plus early cranioplasty has been the ...
Budgell Brian S - - 2007
OBJECTIVE: The primary aims of this study were to determine the major frequencies and powers of oscillations in cerebrospinal fluid (CSF) pressure in the anesthetized rat, and determine whether the CSF pressure oscillations correlated with the major oscillation frequencies in the cardiovascular and respiratory systems as proposed by some chiropractic ...
Kurschel Senta - - 2007
OBJECTIVE: To present clinical and morphological findings before and after surgery in a child with Chairi I malformation (CMI) and intra-cranial hypertension (IH). The literature is reviewed and pathophysiologic factors are discussed. CLINICAL PRESENTATION: A 13-year-old obese boy with a 3-week history of headaches, neck pain, torticollis and progressive visual ...
Greitz Dan - - 2007
This study aims to question the generally accepted cerebrospinal fluid (CSF) bulk flow theory suggesting that the CSF is exclusively absorbed by the arachnoid villi and that the cause of hydrocephalus is a CSF absorption deficit. In addition, this study aims to briefly describe the new hydrodynamic concept of hydrocephalus ...
Tullberg M - - 2007
Normal pressure hydrocephalus (NPH) is characterized by disturbed cerebrospinal fluid (CSF) dynamics and white matter lesions (WML). Although the morphology of these lesions is described, little is known about the biochemistry. Our aim was to explore the relationship between ventricular CSF markers, periventricular WML and postoperative clinical outcome in patients ...
Weigang E - - 2007
BACKGROUND: Paraplegia remains the most dreaded complication following thoracoabdominal aortic repair. We investigated the efficacy of cerebrospinal fluid drainage as a spinal cord-protecting modality. We also evaluated the correlation between the frequency of cerebrospinal fluid drainage and the Crawford classification. METHODS: Spinal cord function was monitored during 20 open surgical ...
Yoshitani Kenji - - 2007
BACKGROUND: Previous studies documented that near-infrared spectroscopy values were affected by factors related to optical path length, such as hemoglobin concentration, the differential path length factor, skull thickness (t-skull), and the area of the cerebrospinal fluid layer (a-CSFL). Lately, the NIRO-100 (Hamamatsu Photonics, Hamamatsu, Japan) has provided a tissue oxygen ...
Andersson Nina - - 2007
Outflow conductance (C(out)) is important for predicting shunt responsiveness in patients with suspected idiopathic adult hydrocephalus syndrome (IAHS). C (out) is determined by performing an infusion test into the cerebrospinal fluid system, and the reliability of the test is dependent on the measurement time. The objective of this study was ...
Olmez Akgün - - 2007
Increased intracranial pressure can rarely be the initial symptom in subacute sclerosing panencephalitis (SSPE). We examined cerebrospinal fluid (CSF) pressures and their correlation with clinical features in 58 patients with SSPE. CSF pressure varied between 50 and 500 mmH2O, mean 210.9+/-103.7 mmH2O. Twenty-five (42%) patients had pressures above 200 mmH2O ...
Yamamoto Masami - - 2007
Thoracoamniotic shunting in fetal pleural effusion has poor results, with an overall survival of less than 50% when hydrops is associated. Those cases without hydrops presented the best evolution, but the indication in these cases remains controversial. We present a dichorionic diamniotic twin pregnancy at 29 weeks' with right pleural ...
Czosnyka Marek M Academic Neurosurgical Unit, Addenbrooke's Hospital, Cambridge, United Kingdom. mc141@medschl.cam.ac.uk - - 2007
Apart from its mean value, the pulse waveform of intracranial pressure (ICP) is an essential element of pressure recording. The authors reviewed their experience with the measurement and interpretation of ICP pulse amplitude by referring to a database of recordings in hydrocephalic patients. The database contained computerized pressure recordings from ...
Cresswell A B - - 2007
A better understanding of intra-abdominal hypertension with relation to the liver is vital to the management of all forms of liver pathophysiology. Supporting good hepatic function within the critically ill patient is important not only in maintaining synthetic function, but also in avoiding the multi-organ complications of liver dysfunction. The ...
Kaiser Gernot M - - 2007
Cerebral oedema and encephalopathy have been noted to occur frequently in patients severely ill or dying after trauma, ischaemia, infections or even metabolic disorders. The objective of the present study was to establish continuous monitoring of the intracranial pressure (ICP) and sampling of cerebrospinal fluid (CSF) for further investigations in ...
Lavinsky Jacó - - 2007
BACKGROUND: Choroidal folds may be caused by several underlying ocular and orbital diseases; they are classified as idiopathic when no obvious cause is found. The objective of this study was to determine whether acquired choroidal folds are associated with idiopathic intracranial hypertension. METHODS: In this observational case series, three patients ...
Whiteley W W Division of Clinical Neurosciences, University of Edinburgh, UK. - - 2006
We prospectively recorded CSF opening pressure in 242 adults who had a lumbar puncture with concomitant measurement of weight and height. The 95% reference interval for lumbar CSF opening pressure was 10 to 25 cm CSF. Body mass index had a small but clinically insignificant influence on CSF opening pressure.
Wilson Robin K - - 2006
Normal pressure hydrocephalus (NPH) is a reversible disorder characterized by gait impairment, subcortical dementia, and urinary urgency and incontinence associated with impaired cerebrospinal fluid circulation and ventriculomegaly. Treatment with shunt surgery is most likely to increase mobility, and may also improve dementia and urinary symptoms. An international, independent study group ...
Brean A - - 2006
We report a 48-year-old man treated for acute subarachnoid hemorrhage (SAH) wherein intracranial pressure (ICP) was measured simultaneously within the ventricular cerebrospinal fluid (CSF) and the brain parenchyma (PAR). Single pressure waves within the continuous pressure signal were identified with determination of the single wave parameters pulse amplitude (i.e. pressure ...
Bradley William G WG - - 2006
PURPOSE: To determine if normal pressure hydrocephalus (NPH) could result from decreased resorption of cerebrospinal fluid (CSF) by the arachnoidal villi, leading to benign external hydrocephalus [BEH] in infancy, followed by deep white matter ischemia (DWMI) in late adulthood (the more hydrophilic environment increasing resistance to CSF flow through the ...
Clarke Michelle J - - 2006
Low-pressure hydrocephalus is an extremely rare condition. Authors of the few previous reports on this subject have suggested that symptoms are gradual in onset and successfully treated. In this report the authors presented two unique cases of very low pressure hydrocephalus in which the patients experienced rapid deterioration requiring negative-pressure ...
Voigtmann Th - - 2006
Whether glass formation is mainly driven by temperature or by pressure is an open question that is now being addressed in high-pressure experiments. Here we propose that some insight into these questions could be gained by comparing in a suitable manner with colloidal glass-transition data. Based on such a comparison, ...
Stephensen Hannes - - 2006
OBJECTIVE: To record the levels of intracranial pressure (ICP) during wakefulness and sleep in hydrocephalic adults and to correlate the ICP levels with symptoms and degree of improvement after surgical treatment. METHODS: ICP and patient behavior were registered overnight (17-26 h) in 29 patients with noncommunicating and 26 with communicating ...
Grzybowski Deborah M - - 2006
PURPOSE: To describe and validate an in vitro model of the arachnoid granulation (AG) outflow pathway for cerebrospinal fluid (CSF), by using human AG cells grown on a filter membrane support and perfused in a modified Ussing chamber at pressures analogous to normal human intracranial pressures. METHODS: Human AG cells ...
Jivraj Sana - - 2006
PURPOSE: Labetalol is an effective antihypertensive medication frequently used to treat systemic hypertension in acute care settings, including the management of hypertension associated with a subarachnoid hemorrhage. We present a case of profound hypotension, refractory to inotropic and vasopressor therapy following an iv infusion of labetalol. CLINICAL FEATURES: Initiation of ...
Huh Pil-Woo - - 2006
OBJECT: The various terms used to describe subdural fluid collection--"external hydrocephalus", "subdural hygroma", "subdural effusion", "benign subdural collection", and "extraventricular obstructive hydrocephalus"-reflect the confusion surrounding the diagnoses of these diseases. Differentiating external hydrocephalus from simple subdural hygroma may be difficult, but the former appears to be a distinct clinical entity ...
Wirth Benedikt - - 2006
We formulate in general terms the equations for axisymmetric and fully 3D models of a hydrocephalic brain. The model is developed using small strain poroelasticity that includes non-linear permeability. The axisymmetric model is solved for four ventricle shapes, an ellipsoid, a 'peanut' shape, a 'cross' shape and a 'bone' shape. ...
Grundmann Sebastian - - 2006
A growing number of patients suffer from peripheral artery disease (PAD). Current therapies are often limited by the extent of vascular pathology and the occurrence of restenosis after angioplasty. The stimulatory effect of growth factor administration on collateral vessel formation (arteriogenesis) has evolved as a potential new treatment for this ...
Greitz Dan - - 2006
The pathophysiology of syringomyelia development is not fully understood. Current prevailing theories suggest that increased pulse pressure in the subarachnoid space forces cerebrospinal fluid (CSF) through the spinal cord into the syrinx. It is generally accepted that the syrinx consists of CSF. The here-proposed intramedullary pulse pressure theory instead suggests ...
Factora Ronan - - 2006
The Adams triad (gait impairment, dementia, and urinary incontinence) of normal pressure hydrocephalus (NPH) is well known, but other illnesses present with similar symptoms. Accurate diagnosis of this rare disorder depends on careful evaluation. A ventriculoperitoneal shunt is the only effective therapy, and deciding whether the patient will benefit is ...
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