Search results for "shunt"

showing 10 items of 114 documents

Current Concepts and Perspectives on Brain Arteriovenous Malformations: A Review of Pathogenesis and Multidisciplinary Treatment.

2021

Brain arteriovenous malformations (bAVMs) are unusual vascular pathologies characterized by the abnormal aggregation of dilated arteries and veins in the brain parenchyma and for which the absence of a normal vascular structure and capillary bed leads to direct connections between arteries and veins. Although bAVMs have long been believed to be congenital anomalies that develop during the prenatal period, current studies show that inflammation is associated with AVM genesis, growth, and rupture. Interventional treatment options include microsurgery, stereotactic radiosurgery, and endovascular embolization, and management often comprises a multidisciplinary combination of these modalities. T…

Intracranial Arteriovenous Malformationsmedicine.medical_specialtyMicrosurgerymedicine.medical_treatmentNeurosurgeryArteriovenous shuntNervous System MalformationsRadiosurgeryRadiosurgeryPathogenesisArteriovenous malformationMultidisciplinary approachmedicineHumansEmbolizationRetrospective StudiesNatural courseInterventional treatmentbusiness.industryBrainMicrosurgeryAVMEmbolization TherapeuticPathobiologyTreatment OutcomeMultimodalSurgeryNeurology (clinical)NeurosurgeryRadiologybusinessWorld neurosurgery
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Removing Leakage and Surface Recombination in Planar Perovskite Solar Cells

2019

Thin-film solar cells suffer from various types of recombination, of which leakage current usually dominates at lower voltages. Herein, we demonstrate first a three-order reduction of the shunt loss mechanism in planar methylammonium lead iodide perovskite solar cells by replacing the commonly used hole transport layer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) with a better hole-selective polyarylamine. As a result, these cells exhibit superior operation under reduced light conditions, which we demonstrate for the extreme case of moonlight irradiance, at which open-circuit voltages of 530 mV can still be obtained. By the shunt removal we also observe the VOC to dro…

IodideFOS: Physical sciencesEnergy Engineering and Power TechnologyHole transport layerApplied Physics (physics.app-ph)02 engineering and technology010402 general chemistry01 natural sciencesPlanarPEDOT:PSSMaterials ChemistryLeakage (electronics)chemistry.chemical_classificationRenewable Energy Sustainability and the Environmentbusiness.industryPhysics - Applied Physics021001 nanoscience & nanotechnology0104 chemical sciencesFuel TechnologychemistryChemistry (miscellaneous)Optoelectronics0210 nano-technologybusinessShunt (electrical)RecombinationVoltage
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Transjugular intrahepatic portosystemic shunt (TIPS) complications: what diagnostic radiologists should know

2022

Transjugular intrahepatic portosystemic shunt (TIPS) is an effective therapy for portal hypertension complications and can successfully treat variceal bleeding and refractory ascites. Although TIPS is relatively safe, procedural- or shunt-related morbidity can reach 20%, and procedural complications have a fatality rate of 2%. Delayed recognition and treatment of TIPS complications can lead to life-threatening clinical scenarios. Complications can vary from stent migration or malpositioning to nontarget organ injury, TIPS dysfunction, encephalopathy, or liver failure. This review aims to outline the role of diagnostic radiology in assessing post-TIPS complications.[GRAPHICS].

Liver CirrhosisComplicationsRadiological and Ultrasound TechnologyUrologyGastroenterologyEsophageal and Gastric VaricesTransjugular intrahepatic portosystemic shuntImagingTreatment OutcomeHepatic EncephalopathyRadiologistsTIPSHumansRadiology Nuclear Medicine and imagingPortasystemic Shunt Transjugular IntrahepaticGastrointestinal HemorrhageAbdominal Radiology
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TIPS for Prevention of Recurrent Bleeding in Patients with Cirrhosis: Meta-analysis of Randomized Clinical Trials

1999

To compare the effects of transjugular intrahepatic portosystemic shunt (TIPS) creation with those of endoscopic treatment with or without propranolol administration (i.e, conventional treatment) on recurrent bleeding, encephalopathy, and mortality by using meta-analysis of 11 published randomized clinical trials.Data from 11 relevant studies were retrieved by means of computerized and manual search. The combinability of the studies was assessed in terms of clinical and statistical criteria. Data were extracted on the basis of the intention-to-treat principle, and treatment effects were measured as risk differences between TIPS creation and conventional treatment. Pooled estimates were comp…

Liver CirrhosisMalemedicine.medical_specialtyCirrhosismedicine.medical_treatmentEncephalopathyEsophageal and Gastric Variceslaw.inventionRandomized controlled trialRecurrenceRisk FactorslawSclerotherapymedicineSclerotherapyHumansRadiology Nuclear Medicine and imagingbusiness.industryLiver DiseasesHemostasis EndoscopicMiddle Agedmedicine.diseaseSurgeryHepatic EncephalopathyMeta-analysisPortal hypertensionFemalePortasystemic Shunt Transjugular IntrahepaticGastrointestinal HemorrhageVaricesbusinessTransjugular intrahepatic portosystemic shuntRadiology
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Transjugular Intrahepatic Portosystemic Shunt for Refractory Ascites: A Meta-analysis of Individual Patient Data

2007

Several randomized controlled trials have compared a transjugular intrahepatic portosystemic shunt (TIPS) with large-volume paracentesis in cirrhotic patients with refractory ascites. Although all agree that TIPS reduces the recurrence rate of ascites, survival is controversial. The aim of this study was to compare the effects of TIPS and large-volume paracentesis in cirrhotic patients with refractory ascites by means of meta-analysis of individual patient data from 4 randomized controlled trials.The study population consisted of 305 patients: 149 allocated to TIPS and 156 to paracentesis. Cumulative probabilities of transplant-free survival and of hepatic encephalopathy (HE) were estimated…

Liver CirrhosisMalemedicine.medical_specialtymedicine.medical_treatmentKaplan-Meier EstimateGastroenterologySpontaneous bacterial peritonitisModel for End-Stage Liver DiseaseHepatorenal syndromeRisk FactorsInternal medicineAscitesmedicineParacentesisHumansParacentesisHepatic encephalopathyAgedFirst episodeHepatologymedicine.diagnostic_testbusiness.industrySodiumGastroenterologyAscitesBilirubinPatient dataMiddle Agedmedicine.diseaseLiver TransplantationSurgeryTreatment OutcomeMeta-analysisHepatic EncephalopathyRegression AnalysisFemaleRefractory ascitesPortasystemic Shunt Transjugular Intrahepaticmedicine.symptombusinessTransjugular intrahepatic portosystemic shuntGastroenterology
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Reply to: “Freiburg index of post-TIPS survival (FIPS) a valid prognostic score in patients with cirrhosis but also an advisor against TIPS?”

2021

Liver Cirrhosismedicine.medical_specialtyCirrhosisIndex (economics)Hepatologybusiness.industryPrognosismedicine.diseasePrognostic scoreText miningInternal medicinemedicineHumansIn patientPortasystemic Shunt Transjugular IntrahepaticbusinessJournal of Hepatology
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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…

MaleIntracranial PressureUltrasonography Doppler TranscranialVentriculoperitoneal ShuntPostoperative ComplicationsCerebrospinal Fluid PressureMonitoring Intraoperativemedicine.arterymedicineHumansCerebral perfusion pressureChildTranscranial doppler Hydrocephalus pediatric patientsbusiness.industrySettore MED/27 - NeurochirurgiaBrainInfantGeneral Medicinemedicine.diseaseHydrocephalusTranscranial DopplerShuntingmedicine.anatomical_structureCerebral blood flowVentricleAnesthesiaPediatrics Perinatology and Child HealthMiddle cerebral arteryCerebral ventriclecardiovascular systemFemaleNeurology (clinical)businessBlood Flow VelocityHydrocephalus
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Late, giant brachial artery aneurysm following hemodialysis fistula ligation in a renal transplant patient: case report and literature review.

2012

Brachial artery aneurysm (BAA) following long-standing arteriovenous fistula ligation after renal transplantation is uncommon. Herein, we describe the case of a 64-year-old man who developed a giant symptomatic BAA 21 years after ligation of the fistula. He was submitted to surgical excision of the aneurysm followed by interposition prosthetic graft.

MalePulmonary and Respiratory Medicinemedicine.medical_specialtyBrachial ArteryFistulamedicine.medical_treatmentArteriovenous fistulaSettore MED/22 - Chirurgia VascolareArteriovenous Shunt SurgicalAneurysmRenal Dialysismedicine.arterymedicineHumanscardiovascular diseasesBrachial arteryLigationbusiness.industryBrachial artery aneurysm Renal transplantation Dialysis Surgical bypassGeneral MedicineMiddle Agedmedicine.diseaseAneurysmKidney TransplantationSurgeryTransplantationCardiothoracic surgerycardiovascular systemSurgeryRadiologyHemodialysisCardiology and Cardiovascular MedicineLigationbusiness
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CSF shunt infections in children

1993

The incidence of shunt infections and possible risk factors was investigated by chart analysis. From 1986 to 1989 350 shunt procedures were performed including 273 ventriculoperitoneal shunts and 75 ventriculoatrial shunts. Twenty-eight infectious episodes (8%) occurred in 25 patients during a median follow-up time of 20 months. For 204 patients the follow-up time could be prolonged until September 1992. In these patients no infectious episodes occurred in the extended observation period. In 24 cases (85.7%) a causative organism could be isolated. The infecting organisms were gram-positive cocci in 22 cases (78.6%) and gram-negative bacilli in two cases. The main signs and symptoms were fev…

MaleReoperationMicrobiology (medical)medicine.medical_specialtyAbdominal painAdolescentmedicine.drug_classAntibioticsVentriculoperitoneal ShuntRecurrenceRisk FactorsmedicineHumansHeart AtriaDerivationChildGram-Positive Bacterial InfectionsAntibacterial agentbusiness.industryInfant NewbornInfantGeneral Medicinemedicine.diseaseCerebrospinal Fluid ShuntsAnti-Bacterial AgentsSurgeryHydrocephalusInfectious DiseasesChild PreschoolEtiologyFemalemedicine.symptomGram-Negative Bacterial InfectionsComplicationbusinessShunt (electrical)Follow-Up StudiesHydrocephalusInfection
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Antibiotic single-dose prophylaxis of shunt infections.

1989

Shunt infections after implantation or revision of a shunt for CSF drainage in hydrocephalic patients are serious complications. In view of their frequency, this study investigated the efficacy of prophylactic administration of a single dose of the antibiotic cefazedone in reducing in the post-operative infection rate. Fifty children of up to 14 years of age suffering from hydrocephalus of various etiologies were treated prophylactically and compared with a similar untreated group. The diagnosis of infection was based mainly on microbiological and clinical observations and investigations. Classical infection parameters were also recorded and evaluated, but played only a secondary role in es…

Malemedicine.medical_specialtyAdolescentmedicine.drug_classmedicine.medical_treatmentAntibioticsInfectionsDrug Administration ScheduleCefazedoneCefazolinmedicineHumansDerivationProspective StudiesChildChemotherapyInfection Controlbusiness.industryInfant NewbornInfantDrug Resistance MicrobialGeneral Medicinemedicine.diseaseCerebrospinal Fluid ShuntsHydrocephalusShunt (medical)SurgeryAnti-Bacterial AgentsAnesthesiaChild PreschoolSurgeryFemaleNeurology (clinical)NeurosurgeryComplicationbusinessmedicine.drugNeurosurgical review
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