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OBJECTIVE: To evaluate the findings of magnetic resonance angiography (MRA) and transcranial Doppler ultrasound (TCD) in patients with a clinical diagnosis of vertebrobasilar insufficiency (VBI). METHOD: From our outpatient neurotology clinic, we selected patients (using the criteria proposed by Grad and Baloh) with a clinical diagnosis of VBI. We excluded patients with any definite cause for vestibular symptoms, a noncontrolled metabolic disease or any contraindication to MRA or TCD. The patients in the study group were sex- and age-matched with subjects who did not have vestibular symptoms (control group). Our final group of patients included 24 patients (study, n=12; control, n=12). RESULTS: The MRA results did not demonstrate significant differences in the findings between our study and control groups. TCD demonstrated that the systolic pulse velocity of the right middle cerebral artery, end diastolic velocity of the basilar artery, pulsatility index (PI) of the left middle cerebral artery, PI of the right middle cerebral artery, and PI of the basilar artery were significantly higher in the study group than in the control group, suggesting abnormalities affecting the microcirculation of patients with a clinical diagnosis of VBI compared with controls. CONCLUSION: MRA failed to reveal abnormalities in patients with a clinical diagnosis of VBI compared with controls. The PI of the basilar artery, measured using TCD, demonstrated high sensitivity (91%) and specificity (91%) for detecting clinically diagnosed VBI.
Subject(s)
Humans , Basilar Artery/diagnostic imaging , Vertebrobasilar Insufficiency/diagnostic imaging , Ultrasonography, Doppler, Transcranial/methods , Magnetic Resonance Angiography , Blood Flow Velocity , MicrocirculationABSTRACT
Abstract Introduction Vertebrobasilar insufficiency is defined as transitory ischemia of the vertebrobasilar circulation. Dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body are the most common symptoms. Objective To review the literature regarding the three available diagnostic testing in patients with dizziness complaints secondary to vertebrobasilar insufficiency (VBI): magnetic resonance angiography; transcranial Doppler ultrasound; and vertebrobasilar deprivation testing. Data Synthesis We selected 28 studies that complied with our selection criteria for appraisal. The most frequent cause of the hemodynamic changes leading to VBI is atherosclerosis. The main clinical symptoms are dizziness, vertigo, headaches, vomit, diplopia, blindness, ataxia, imbalance, and weakness in both sides of the body. Even though arteriography is considered the most important exam to diagnose the disease, the inherent risks of this exam should be taken into consideration. The magnetic resonance angiography has been widely studied and is a good method to identify and localize any occlusions and stenosis in both neck and intracranial great vessels. Conclusion Each patient with a suspected diagnosis of VBI should be individually evaluated and treated, taking in consideration the pros and cons of each diagnostic testing and treatment option.
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ABSTRACT Intracranial hypertension and brain swelling are a major cause of morbidity and mortality of patients suffering from fulminant hepatic failure (FHF). The pathogenesis of these complications has been investigated in man, in experimental models and in isolated cell systems. Currently, the mechanism underlying cerebral edema and intracranial hypertension in the presence of FHF is multi-factorial in etiology and only partially understood. The aim of this paper is to review the pathophysiology of cerebral hemodynamic and metabolism changes in FHF in order to improve understanding of intracranial dynamics complication in FHF.
RESUMO O edema cerebral e a hipertensão intracraniana (HIC) são as principais causas de morbidade e mortalidade de pacientes com insuficiência hepática fulminante (IHF). A patogênese dessas complicações tem sido investigada no homem, em modelos experimentais e em sistemas celulares isolados. Atualmente, o mecanismo subjacente ao edema cerebral e HIC na presença de IHF é multifatorial em etiologia e pouco compreendido na literatura. O objetivo deste trabalho é revisar a fisiopatologia das alterações hemodinâmicas e metabólicas cerebrais na IHF, visando melhorar a compreensão da complicação da hemodinâmica encefálica na IHF.
Subject(s)
Humans , Brain Edema/etiology , Cerebrovascular Circulation/physiology , Liver Failure, Acute/complications , Intracranial Hypertension/etiology , Brain Edema/physiopathology , Hepatic Encephalopathy/etiology , Hepatic Encephalopathy/physiopathology , Hepatic Encephalopathy/metabolism , Liver Failure, Acute/physiopathology , Liver Failure, Acute/metabolism , Intracranial Hypertension/physiopathologyABSTRACT
ABSTRACT Introduction Treatment of hydrocephalus is accomplished primarily through a ventricular-peritoneal shunt (VPS). This study aims to describe the application of retrograde ventricle-sinus shunt (RVSS) in patients with hydrocephalus after surgical treatment of myelomeningocele. Method A prospective, randomized and controlled pilot study. We consecutively enrolled 9 patients with hydrocephalus after surgical repair of myelomeningocele from January 2010 to January 2012. These patients underwent elective RVSS or VPS. Five underwent RVSS and 4 underwent VPS. Patients were followed for one year with quarterly evaluations and application of transcranial Doppler. Results RVSS group showed outcomes similar to those of VPS group. Doppler revealed significant improvement when comparing preoperative to postoperative period. RVSS group had significantly higher cephalic perimeter than VPS group. Neuropsychomotor development, complications and subjective outcomes did not differ between groups. Conclusion RVSS shunt is viable; it is an alternative option for the treatment of hydrocephalus.
RESUMO O tratamento da hidrocefalia é realizado principalmente através de uma derivação ventrículo-peritoneal (DVP). Nosso objetivo é descrever a aplicação da derivação ventrículo-sinusal retrógrada (DVSR) em pacientes com hidrocefalia após o tratamento cirúrgico de mielomeningocele. Método Estudo prospectivo, randomizado e controlado. Selecionados consecutivamente 9 pacientes com hidrocefalia após correção cirúrgica de mielomeningocele de janeiro de 2010 a janeiro de 2012. Eles foram submetidos à DVSR ou DVP. Cinco foram submetidos à DVSR e 4 à DVP. Foram seguidos por 1 ano com realização trimestral de avaliações e aplicação do Doppler transcraniano. Resultados O grupo DVSR apresentou desfechos semelhantes ao grupo DVP. O Doppler mostrou melhora significativa quando comparado o pré-operatório com o pós-operatório. O grupo DVSR apresentou perímetro cefálico significativamente maior que o grupo DVP. O desenvolvimento neuropsicomotor e complicações não diferiram entre os grupos. Conclusão A derivação ventrículo-sinusal retrógrada é viável; ela é uma opção para o tratamento de hidrocefalia.
Subject(s)
Female , Humans , Infant , Male , Hydrocephalus/surgery , Meningomyelocele/surgery , Ventriculoperitoneal Shunt/methods , Hydrocephalus/etiology , Meningomyelocele/complications , Prospective Studies , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
Objetivo: Neste trabalho temos o objetivo de avaliar a acura?cia do sistema de aferic?a?o da pressão intracraniana (PIC) epidural com microchip. Me?todos: Foram estudados 27 sui?nos sob anestesia geraI, devidamente assistidos com monitoração ventilatória e hemodina?mica. Durante o experimento foi reproduzido um processo expansivo intracerebral programado no lobo frontal direito. O experimento constou de tre?s grupos (A, B e C) com hipertensão intracraniana gerada com balão reproduzindoum hematoma intracerebral. Em todos os grupos foram calibrados os para?metros normais: os dois sistemas de PIC foram comparados e estudados quanto a? correlação dos valores aferidos. Resultados: O comportamento médio da PIC ao longo dos momentos de avaliac?a?o foi estatisticamente diferente entre os grupos (p < 0,001). A reprodução de ressangramento resultou em elevac?a?o significativa da PIC (p < 0,001). Avaliando-se a acura?cia comparativa geral, verificou-se um coeficiente de correlação intraclasse de 0,8. Conclusa?o: O modelo de hipertensa?o intracraniana por bala?o em sui?nos e? facti?vel e confia?vel na gerac?a?o de hipertensa?o intracraniana. O sistema de aferic?a?o de pressa?o intracranianaepidural apresenta elevado coeficiente de correlac?a?o com o sistema de aferic?a?o parenquimatoso na avaliac?a?o global.
Objective: In this paper we aim to evaluate the accuracy of the measurement with microchip epidural system. Methods: Twenty-seven pigs with were studied, under generaI anesthesia, properly assisted with ventilation and hemodynamic monitoring. During the experiment, we have simulated frontal intracerebral expansive process. The experiment consisted of three groups (A, B and C) with intracranial hypertension generated with the simulation of an intracerebral hematoma. The two systems were compared andstudied as the correlation of the measured values. Results: The average behavior of the increased intracranial pressure (ICP) over the time points are statistically different between groups (p < 0.001). The simulation of rebleeding resulted in a significant increase in ICP (p < 0.001). Evaluating the overall comparative accuracy there was an intraclass correlation coefficient of 0.8. Conclusion: The model of intracranial hypertension balloon in pigs is feasible and reliable in generating intracranial hypertension. The system for measuring intracranial epidural pressure has a high correlation coefficient with the system parenchymal gauging the overall evaluation.
Subject(s)
Animals , Cerebral Hemorrhage , Intracranial Hypertension , Intracranial Pressure , Epidural Space , Models, AnimalABSTRACT
Objective Intracranial hypertension (IH) develops in approximately 50% of all patients with severe traumatic brain injury (TBI). Therefore, it is very important to identify a suitable animal model to study and understand the pathophysiology of refractory IH to develop effective treatments. Methods We describe a new experimental porcine model designed to simulate expansive brain hematoma causing IH. Under anesthesia, IH was simulated with a balloon insufflation. The IH variables were measured with intracranial pressure (ICP) parenchymal monitoring, epidural, cerebral oximetry, and transcranial Doppler (TCD). Results None of the animals died during the experiment. The ICP epidural showed a slower rise compared with parenchymal ICP. We found a correlation between ICP and cerebral oximetry. Conclusion The model described here seems useful to understand some of the pathophysiological characteristics of acute IH. .
Objetivo A hipertensão intracraniana (HIC) ocorre em até 50% de todos os pacientes com traumatismo cranioencefálico (TCE). Por isso, é importante estabelecer um modelo animal adequado para estudar a fisiopatologia da HIC refratária, com a perspectiva de desenvolver tratamentos eficazes. Métodos Os animais foram submetidos a um protocolo padrão de anestesia. A hipertensão intracraniana foi estabelecida através de insuflação de um balão. As variáveis HIC foram medidas com a pressão intracraniana (PIC) do parênquima, oximetria, epidural e doppler transcraniano. Resultados A PIC epidural apresentou elevação mais lenta, comparada com a PIC parenquimal. Houve correlação entre a PIC e a oximetria cerebral. O registro da PIC, oximetria e índice de pulsatilidade foi realizado em todos os animais sem dificuldade. Conclusão O modelo descrito parece ser útil para a compreensão de algumas características fisiopatológicas na HIC aguda. .
Subject(s)
Animals , Disease Models, Animal , Intracranial Hypertension/physiopathology , Neurophysiological Monitoring/methods , Acute Disease , Algorithms , Oximetry , Pilot Projects , Reference Values , Reproducibility of Results , Swine , Time Factors , Ultrasonography, Doppler, TranscranialABSTRACT
Brain metastases (BM) are one of the most common intracranial tumors and surgical treatment can improve both the functional outcomes and patient survival, particularly when systemic disease is controlled. Image-guided BM resection using intraoperative exams, such as intraoperative ultrasound (IOUS), can lead to better surgical results. METHODS: To evaluate the use of IOUS for BM resection, 20 consecutives patients were operated using IOUS to locate tumors, identify their anatomical relationships and surgical cavity after resection. Technical difficulties, complications, recurrence and survival rates were noted. RESULTS: IOUS proved effective for locating, determining borders and defining the anatomical relationships of BM, as well as to identify incomplete tumor resection. No complications related to IOUS were seen. CONCLUSION: IOUS is a practical supporting method for the resection of BM, but further studies comparing this method with other intraoperative exams are needed to evaluate its actual contribution and reliability.
As metástases cerebrais (MC) são os tumores intracranianos mais frequentes e seu tratamento cirúrgico pode melhorar a sobrevida e a funcionalidade do paciente, especialmente quando a doença sistêmica está controlada. A ressecção das MC guiada por imagens de exames intraoperatórios, como ultrassom intraoperatório (USIO), pode levar a melhores resultados cirúrgicos. MÉTODOS: Avaliar o uso do USIO nas ressecções de MC de 20 pacientes para localizar os tumores, avaliar suas relações anatômicas e a cavidade cirúrgica após o procedimento. As dificuldades técnicas, complicações, recorrência e taxa de sobrevivência foram anotadas em cada caso. RESULTADOS: USIO foi eficaz para localizar, delinear e definir as relações anatômicas das MC, assim como a ocorrência de ressecção incompleta. Não foram encontradas complicações relacionadas ao uso do USIO. CONCLUSÃO: USIO é um método auxiliar prático para as ressecções de MC, porém outros estudos ainda se fazem necessários para avaliar sua real contribuição nesses procedimentos.