Search results for "Shunting"

Rifampin-impregnated silicone catheters: a potential tool for prevention and treatment of CSF shunt infections.

2003

Background: Infection continues to be one of the major complications of cerebro-spinal fluid shunting procedures. Recent insights in the pathophysiological mechanism of these foreign body infections have elucidated the difficulty of achieving successful treatment without device removal. The development of a rifampin-impregnated silicone catheter yielded excellent results in infection prevention and treatment in vitro as well as in an animal model. Patients and Methods: Here, we describe the application of this device in two patients with a complicated course of shunt infection. Results: In one patient the rifampin-impregnated shunt system was implanted after external drainage to prevent fur…

PROSAIKA: A prospective multicenter registry with the first programmable gravitational device for hydrocephalus shunting

2015

Abstract Objective Cerebrospinal fluid (CSF) overdrainage is a major problem in shunt therapy for hydrocephalus. The adjustable gravitational valve proSA allows for the first time a targeted compensation for overdrainage in the upright position without interfering with the differential pressure valve. To evaluate benefit, safety and reliability, the multicenter prospective registry PROSAIKA was conducted in 10 German neurosurgical centers. Methods Between March 2009 and July 2010, 120 hydrocephalic patients undergoing first time shunt implantation or shunt revision using proSA entered the study. 93 patients completed the 12 months follow-up. Results Hydrocephalus symptoms were improved in 8…

Arterial O2-Partial Pressure at Positve Endexpiratory Pressure in Hyperoxia for Verification of Patent Foramen Ovale?

1990

As a rule, during anaesthesia a time dependent increase in pulmonary shunting occurs even in states of normal lung function. Therefore positive end-expiratory pressure ventilation (PEEP) is often used to decrease intrapulmonary right/left shunting (RL shunt) and thus to increase arterial O2 partial pressure (paO2) without increasing the inspiratory oxygen fraction.

TRESK channel contributes to depolarization-induced shunting inhibition and modulates epileptic seizures.

2020

Glutamatergic and GABAergic synaptic transmission controls excitation and inhibition of postsynaptic neurons, whereas activity of ion channels modulates neuronal intrinsic excitability. However, it is unclear how excessive neuronal excitation affects intrinsic inhibition to regain homeostatic stability under physiological or pathophysiological conditions. Here, we report that a seizure-like sustained depolarization can induce short-term inhibition of hippocampal CA3 neurons via a mechanism of membrane shunting. This depolarization-induced shunting inhibition (DShI) mediates a non-synaptic, but neuronal intrinsic, short-term plasticity that is able to suppress action potential generation and…

Intraoperative monitoring of cerebral blood flow during ventricular shunting in hydrocephalic pediatric patients.

1995

Several studies have demonstrated lowered cerebral blood flow (CBF) in patients with hydrocephalus and symptoms of raised intracranial pressure. Ventricular shunting in such cases permits a sudden increase in CBF. The pathophysiology of functional brain deficit secondary to hydrocephalus is little understood. Improvement of the patient's clinical status after drainage of CSF suggests that cerebral dysfunction is not necessarily due to permanent brain damage. In fact, it improves rapidly after ventricular taps. In view of this it would be helpful to monitor cerebral perfusion. The transcranial Doppler (TCD) ultrasonography technique allows real-time monitoring of the intracranial circulation…

Letter: Cerebrospinal Fluid Shunting Improves Long-Term Quality of Life in Idiopathic Normal Pressure Hydrocephalus.

2020

Effect of depolarizing GABAA-mediated membrane responses on excitability of Cajal-Retzius cells in the immature rat neocortex

2011

In immature neurons activation of ionotropic GABA receptors induces depolarizing membrane responses due to a high intracellular Cl− concentration ([Cl−]i). However, it is difficult to draw conclusions about the functional consequences of subthreshold GABAergic depolarizations, since GABAergic membrane shunting and additional effects on voltage-dependent ion channels or action potential threshold must be considered. To systematically investigate factors that determine the GABAergic effect on neuronal excitability we performed whole cell patch-clamp recordings from Cajal-Retzius cells in immature rat neocortex, using [Cl−]i between 10 and 50 mM. The effect of focal GABA application was quant…

Hypoplasia of the posterior mitral valve leaflet: Don't forget to look beyond the mitral valve.

2020

Hypoplasia of the posterior mitral valve leaflet (PMVL) is a very rare finding in adulthood and can coexist with other congenital heart defects. In this image, a transesophageal echocardiography (TOE) carried out on a 59-year-old woman with a 2-month history of dyspnea revealed a hypoplastic PMVL causing severe mitral regurgitation associated with a secundum-type atrial septal defect (ASD) with left-to-right shunting. This case demonstrates how essential 3-dimensional TOE is for a comprehensive assessment of the mitral valve and to improve the diagnostic accuracy of concomitant congenital heart abnormalities.

Cerebral arachnoid cyst: a lesion of the child's brain.

1989

39 patients with 42 arachnoid cysts have been reviewed in a retrospective study. All kinds of arachnoid cysts reported in the literature were also found in this study. These consist mainly of congenital primary and post-traumatic secondary cysts. Cysts which cause no major neurological deficits require conservative treatment of symptoms only. Cysts which cause major symptoms because of their space occupying nature, however, require surgical treatment. Craniotomy with removal of membranes to allow free physiological circulation of CSF is the treatment of choice in our hands. Cysto-peritoneal shunting is an alternative procedure for patients in a poor condition. More than 50% (23 out of 39 ca…

Investigation of the Temperature Sensitivity of 20-Years Old Field-Aged Photovoltaic Panels Affected by Potential Induced Degradation

2022

One effect of moisture ingress on solar panels is potential induced degradation (PID). Solar panels affected by PID experience large leakage currents between the solar cells and the module’s frame, which leads to substantial power degradation. In the present work, the temperature coefficients of 3 old PV panels affected by PID were investigated. In the electroluminescence images, solar cells nearer to the edge of the modules appear darker due to ohmic shunting. IR thermal images acquired under clear sky outdoor conditions show that the majority of the warmer cells (hotspots) were located closer to the edge of the modules. The difference in cell temperature (∆T) due to PID effect…