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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

Restarting Oral Anticoagulant in Patients with Mechanical Heart Valve(s) and Intracranial Haemorrhage

Alkherayf, Fahad 07 December 2012 (has links)
Patients with mechanical heart valves who present with intracranial haemorrhage are initially treated by reversing their coagulopathy. However, these patients will ultimately require that their oral anticoagulant be restarted. The time at which oral anticoagulants are restarted is critical since restarting too early may increase the risk of recurrent bleeding, while withholding anticoagulants increases the patient’s risk of thromboembolic events. The ideal time to restart patients on their oral anticoagulant medication is defined as the time at which all these risks are minimized. This thesis includes a systematic review and meta-analysis of the literature. The main outcomes were recurrent haematoma, valve thrombosis, stroke and peripheral emboli. Results were stratified by types of intracranial haemorrhage. We also conducted a survey to gain insight into current practices of neurosurgeons and thrombosis experts in Canada and USA when they are faced with deciding on anticoagulant restart times in patients with ICH. Results were stratified by type of intracranial bleed and participants’ characteristics and demographics. The systematic review identified that the ideal time for restarting anticoagulant therapy in patients following an ICH is unknown. Meta-analysis was limited by the heterogeneity of the studies. The survey results indicated that physicians had a wide range of practice and that their practice was dependent on the patient’s clinical features, but many physicians would restart oral anticoagulants between 4 and 14 days after the haemorrhage. For this reason we have proposed a multi centre cohort study to investigate the safety and efficacy of restarting patients on anticoagulation therapy between day 5 and 9 post haemorrhage. A full study protocol is presented in this thesis.
192

Developing a Minimally Invasive Sustained Release System for Glioma Therapy

Kao, Chen-Yu 16 November 2007 (has links)
Malignant brain tumor is one of the most lethal forms of cancers. In the United States alone, approximately 20,500 new cases of primary malignant brain and central nervous system tumors are expected to be diagnosed in 2007 with 12,740 deaths estimated. Treatment of malignant brain tumor remains a major challenge despite recent advance in surgery and other adjuvant therapies, such as chemotherapy. The failure of potential effective chemotherapeutics for brain tumor treatment is usually not due to the lack of potency of the drug, but rather can be attributed to lack of therapeutic strategies capable of overcoming blood brain barrier for effective delivery of drug to the brain tumor. In this thesis, we developed a minimally invasive sustained release system for glioma therapy. The present study was initiated in an effort to incorporated Doxorubicin (DOX) loaded PLGA particle into an agarose gel, which can provide a continuous release of DOX locally to the tumor site. DOX, a toposiomearase II inhibitor, is not currently used clinically for brain tumor treatment because when delivered systemically it does not cross BBB. Our hydrogel particle system can overcome this shortcoming of DOX. The results from this study demonstrate that the DOX/PLGA particle gel system can maintain the bioactivity of DOX and sustained release DOX for at least 15 day in vitro. The result of in vivo study showed the DOX/PLGA particle gel treated group had significantly extend the medium survival of 9L glioma bearing rat from 21 days to 29 days. Therefore, the success experience of this local and sustained delivery device might benefit the development of future glioma therapy strategy.
193

Identifiering och omvårdnadsåtgärder vid intrakraniell hypertension. En observationsstudie.

Lindgren, Christina, Reimers, Jenny January 2015 (has links)
SAMMANFATTNING Bakgrund Traumatisk skallskada drabbar relativt många och leder till personligt lidande och finansiell belastning för individ och samhälle då majoriteten får en svår till medelsvår funktionsnedsättning efter vårdtiden. På 1970-talet påvisades ett signifikant samband mellan högt ICP och sekundära hjärnskador. I studier där ICP >20 mmHg har förekommit kunde signifikant sämre utfall ses. Syfte Syftet med studien var att med hjälp av omvårdnadsprocessen observera intensivvårdssjuksköterskans identifiering och vidtagande av omvårdnadsåtgärder vid ett högt ICP samt utvärdera de utförda omvårdnadsåtgärderna.  Metod Prospektiv tvärsnittsundersökning, där sju intensivvårdssjuksköterskor och fem patienter observerades med hjälp av ett observationsformulär. Resultat 51(73 %) av de höga ICP normaliserades inom en minut och intensivvårdssjuksköterskan uppskattades ha observerat högt ICP i 50(71 %) av tillfällena inom en minut. 19(27 %) tillfällen observerades inte och 11(65 %) av omvårdnadsåtgärderna skedde inom en minut. Omvårdnadsåtgärder som utfördes var administrering av bolusdos med läkemedel (35 %) eller dränera likvor (35 %). Efter utförd omvårdnadsåtgärd normaliserades högt ICP inom en till två minuter, 7(41 %), och 4(24 %) normaliserades inom två till tre minuter. Slutsats Majoriteten av tillfällena med högt ICP uppmärksammades inom en minut och vanligast förkommande omvårdnadsåtgärderna var administrering av bolusdos sederande läkemedel eller dränera likvor. Av de tillfällen med intrakraniell hypertension som inte blev observerade var enbart ett par tillfällen ihållande i längre än en minut och samtliga normaliserades spontant inom två minuter. Intensivvårdssjuksköterskorna identifierade och effektivt åtgärdade intrakraniell hypertension snabbt, vilket kan bidra till ett bättre utfall för patienterna. / ABSTRACT Background Due to traumatic brain injury a financial burden is placed on the individual as well as the society and personal suffering also occurs. A significant correlation between elevated ICP and secondary injury was found in the 1970s. Significantly worse outcome was found in a numerous of studies where ICP >20mmHg occurred. Objective The aim of this study was to observe intensive care nurses nursing interventions and its efficiency to decrease ICP by using Orem’s Self-care deficit theory. Methods A prospective observational study. Seven intensive care nurses and five patients were observed. Results 51(73%) of the observed ICP >20mmHg were normalized within the minute. The intensive care nurses were estimated to have observed an on-going intracranial hypertension in 50(71 %) within the minute. 19(27 %) went unnoticed and 11(65 %) of the nursing interventions were executed within the minute. Nursing interventions executed were administration of a sedative (35 %), drainage of cerebrospinal fluid (35 %). Elevated ICP was normalized in 7(41 %) within two minutes and 4(24 %) within three minutes due to the nursing intervention. Conclusion Intensive care nurses noticed the majority of occasions with elevated ICP within one minute. The most commonly used nursing intervention was to administrate a sedative or to drain cerebrospinal fluid. All of the elevated ICP that went unnoticed normalized spontaneously within two minutes. The fast identification of and treated intracranial hypertension are likely to have contributed positively in the patient’s outcome.
194

Cerebral blood flow and intracranial pulsatility studied with MRI : measurement, physiological and pathophysiological aspects

Wåhlin, Anders January 2012 (has links)
During each cardiac cycle pulsatile arterial blood inflates the vascular bed of the brain, forcing cerebrospinal fluid (CSF) and venous blood out of the cranium. Excessive arterial pulsatility may be part of a harmful mechanism causing cognitive decline among elderly. Additionally, restricted venous flow from the brain is suggested as the cause of multiple sclerosis. Addressing hypotheses derived from these observations requires accurate and reliable investigational methods. This work focused on assessing the pulsatile waveform of cerebral arterial, venous and CSF flows. The overall aim of this dissertation was to explore cerebral blood flow and intracranial pulsatility using MRI, with respect to measurement, physiological and pathophysiological aspects. Two-dimensional phase contrast magnetic resonance imaging (2D PCMRI) was used to assess the pulsatile waveforms of cerebral arterial, venous and CSF flow. The repeatability was assessed in healthy young subjects. The 2D PCMRI measurements of cerebral arterial, venous and CSF pulsatility were generally repeatable but the pulsatility decreased systematically during the investigation. A method combining 2D PCMRI measurements with invasive CSF infusion tests to determine the magnitude and distribution of compliance within the craniospinal system was developed and applied in a group of healthy elderly. The intracranial space contained approximately two thirds of the total craniospinal compliance. The magnitude of craniospinal compliance was less than suggested in previous studies. The vascular hypothesis for multiple sclerosis was tested. Venous drainage in the internal jugular veins was compared between healthy controls and multiple sclerosis patients using 2D PCMRI. For both groups, a great variability in the internal jugular flow was observed but no pattern specific to multiple sclerosis could be found. Relationships between regional brain volumes and potential biomarkers of intracranial cardiac-related pulsatile stress were assessed in healthy elderly. The biomarkers were extracted from invasive CSF pressure measurements as well as 2D PCMRI acquisitions. The volumes of temporal cortex, frontal cortex and hippocampus were negatively related to the magnitude of cardiac-related intracranial pulsatility. Finally, a potentially improved workflow to assess the volume of arterial pulsatility using time resolved, four-dimensional phase contrast MRI measurements (4D PCMRI) was evaluated. The measurements showed good agreement with 2D PCMRI acquisitions. In conclusion, this work showed that 2D PCMRI is a feasible tool to study the pulsatile waveforms of cerebral blood and CSF flow. Conventional views regarding the magnitude and distribution of craniospinal compliance was challenged, with important implications regarding the understanding of how intracranial vascular pulsatility is absorbed. A first counterpoint to previous near-uniform observations of obstructions in the internal jugular veins in multiple sclerosis was provided. It was demonstrated that large cardiac- related intracranial pulsatility were related to smaller volumes of brain regions that are important in neurodegenerative diseases among elderly. This represents a strong rationale to further investigate the role of excessive intracranial pulsatility in cognitive impairment and dementia. For that work, 4D PCMRI will facilitate an effective analysis of cerebral blood flow and pulsatility.
195

Vaikų sunkios galvos smegenų traumos baigčių prognoziniai veiksniai / Prognostic factors of outcome after severe traumatic brain injury in children

Grinkevičiūtė, Dovilė 26 September 2008 (has links)
Atliktas perspektyvusis stebėjimo tyrimas, kurio metu buvo tirti sunkią galvos smegenų traumą patyrę vaikai, gydyti KMUK Vaikų intensyviosios terapijos skyriuje. Pacientų būklė pagal GBS vertinta išvykstant iš gydymo įstaigos ir po šešių mėnesių. Darbo tikslas Nustatyti sunkią galvos smegenų traumą patyrusių vaikų ligos baigčių prognozinius veiksnius. Darbo uždaviniai 1. Įvertinti ankstyvas ir vėlyvas sunkią galvos traumą patyrusių vaikų ligos baigtis. 2. Nustatyti sunkią galvos traumą patyrusių vaikų vidinio kaukolės slėgio ir smegenų perfuzinio slėgio ryšį su ligos baigtimis. 3. Nustatyti sunkią galvos traumą patyrusių vaikų traumos pobūdžio ryšį su ligos baigtimis. 4. Nustatyti paciento būkės vertinimo skalių ir laboratorinių tyrimų kritines reikšmes ir jų prognozinę vertę. 5. Nustatyti laboratorinių tyrimų kritines reikšmes ir jų prognozinę vertę. Išgyveno 80,5 proc. sunkią galvos smegenų traumą patyrusių vaikų. Išvykstant iš gydymo įstaigos 50 proc. pacientų, o po šešių mėnesių – 24,2 proc. pacientų traumos baigtis buvos bloga. Įtakos traumos baigtims turėjo kraujavimas po kietuoju smegenų dangalu, smegenų edema, kaukolės kaulų lūžiai. Nustatytos laktatų, gliukozės kiekio kraujo serume, vaikų traumų skalės, Glazgo komų skalės ir vaikų mirštamumo indekso 2 kritinės reikšmės, prognozuojančios mirtį, blogą baigtį išvykstant iš gydymo įstaigos ir po šešių mėnesių. Dekompresinė kraniotomija, atlikta, kai VKS = 24,5 mmHg,o SPS = 46.5 mmHg ligos baigčių nepakeitė. / The prospective observational study involved children after severe traumatic brain injury treated in Pediatric Intensive Care Unit of Kaunas University of Medicine Hospital. The outcome according to Glasgow Outcome Scale was assessed on discharge and after six months The aim of the study was to determine the prognostic factors in children after severe traumatic brain injury. The objectives of the study: 1. To evaluate early and late outcomes in children after severe traumatic brain injury 2. To evaluate the relation of intracranial pressure and cerebral perfusion pressure with outcome in children after severe traumatic brain injury. 3. To evaluate the relation between type of injury and outcome. 4. To determine the threshold values for trauma scoring scales and to evaluate their prognostic significance. 5. To determine the threshold values for laboratory findings and to evaluate their prognostic significance. The survival rate was 80.5 %.half of patients had bad outcome on discharge and 24.4 % – had bad outcome after six months. The prognostic factors of outcome for children after severe traumatic brain injury were subdural hemorrhage, cerebral edema and skull fracture. Threshold values of Pediatric Trauma Score, Glasgow Coma Score and Pediatric index of Mortality 2 for death and bad outcomes on discharge and after six months were ascertained. Decompressive craniectomy performed at ICP ≥ 24.5 mmHg, CPP ≤ 46.5 mmHg had no impact on outcome in children after severe traumatic... [to full text]
196

Investigation of gradient echo MRI for blood vessel imaging and susceptibility-weighted imaging in the human brain

Eissa, Amir Unknown Date
No description available.
197

Restarting Oral Anticoagulant in Patients with Mechanical Heart Valve(s) and Intracranial Haemorrhage

Alkherayf, Fahad 07 December 2012 (has links)
Patients with mechanical heart valves who present with intracranial haemorrhage are initially treated by reversing their coagulopathy. However, these patients will ultimately require that their oral anticoagulant be restarted. The time at which oral anticoagulants are restarted is critical since restarting too early may increase the risk of recurrent bleeding, while withholding anticoagulants increases the patient’s risk of thromboembolic events. The ideal time to restart patients on their oral anticoagulant medication is defined as the time at which all these risks are minimized. This thesis includes a systematic review and meta-analysis of the literature. The main outcomes were recurrent haematoma, valve thrombosis, stroke and peripheral emboli. Results were stratified by types of intracranial haemorrhage. We also conducted a survey to gain insight into current practices of neurosurgeons and thrombosis experts in Canada and USA when they are faced with deciding on anticoagulant restart times in patients with ICH. Results were stratified by type of intracranial bleed and participants’ characteristics and demographics. The systematic review identified that the ideal time for restarting anticoagulant therapy in patients following an ICH is unknown. Meta-analysis was limited by the heterogeneity of the studies. The survey results indicated that physicians had a wide range of practice and that their practice was dependent on the patient’s clinical features, but many physicians would restart oral anticoagulants between 4 and 14 days after the haemorrhage. For this reason we have proposed a multi centre cohort study to investigate the safety and efficacy of restarting patients on anticoagulation therapy between day 5 and 9 post haemorrhage. A full study protocol is presented in this thesis.
198

Using foam-extend to assess the influence of fluid-structure interaction on the rupture of intracranial aneurysms /

Oliveira, Iago Lessa January 2017 (has links)
Orientador: José Luiz Gasche / Resumo: Aneurismas são anormalidades formadas em algumas partes do sistema vascular humano e se caracterizam por regiões dilatadas e finas da parede arterial. Um dos tipos mais comuns ocorre no interior das artérias que chegam ao cérebro, no chamado círculo de Willis. Estes casos de aneurismas intracranianos são extremamente perigosos, pois em caso de rompimento podem ocasionar hemorragia cerebral, com consequente morte ou presença de sequelas permanentes no paciente. As causas dos aneurismas vêm sendo investigadas há tempos, e os pesquisadores concordam que os fenômenos hemodinâmicos têm papel fundamental na formação, crescimento e ruptura do aneurisma cerebral. Entretanto, os procedimentos experimentais para se conhecer melhor as características do escoamento de sangue no interior do aneurisma ainda são de difícil realização. A partir do desenvolvimento de técnicas de mapeamento do sistema vascular cerebral, pôde-se obter a geometria de aneurismas de modo que métodos numéricos na solução de problemas de escoamento passaram a ser utilizados. A partir de então, diversas pesquisas vêm sendo feitas visando a investigação da influência das variáveis biológicas e hemodinâmicas na ruptura do aneurisma. Entretanto, apenas recentemente foi dado foco na influência da interação fluido-estrutura que existe neste problema, devido a flexibilidade da parede da artéria. Assim, usando geometrias de aneurismas específicos de pacientes, simulamos o escoamento sanguíneo utilizando o pacote open-source... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Aneurysms are abnormalities formed in some regions of the human vascular system and are characterized by dilated and thin regions of the arterial wall. One of the most common types occurs inside the brain arteries in the so-called circle of Willis. These intracranial aneurysms are extremely dangerous, because in case of rupture they can cause sub-arachnoid hemorrhage, with consequent death or presence of permanent damage to the patient. Causes of aneurysms have been investigated for a long time, and researchers agree that hemodynamic effects play a key role in the formation, growth, and rupture of brain aneurysms. However, the experimental procedures to better understand the characteristics of blood flow within the aneurysm are still difficult to perform. With the development of scanning techniques of the cerebral vascular system, it has been possible to obtain the geometry of aneurysms and then with that numerical methods for the solution of blood flow have begun to be used. Since then, several researchers have been investigating the influence of biological and hemodynamic variables on aneurysms rupture. However, it has been only in the last decade that the influence of fluid-structure interaction, due to the flexibility of the artery wall, on those variables has been investigated. In this context and using patient-specific aneurysm geometries, we simulated the blood flow using the opensource library foam-extend, which uses a partitioned methodology to numerically solve the ... (Complete abstract click electronic access below) / Résumé: Les anévrismes sont des anomalies formées sur certaines régions du système vasculaire humain et sont caractérisés par des régions dilatées de la paroi artérielle, avec une petite épaisseur. L’un des types les plus communs se produit à l’intérieur des artères de la base du cerveau, dans le cercle de Willis. Ces cas d’anévrismes intracrâniens sont extrêmement dangereux car ils peuvent provoquer une hémorragie sous-arachnoïdienne en cas de rupture, avec la mort ou la présence d’un dommage définitif pour le patient. Les causes d’anévrismes sont étudiées depuis longtemps et des recherches reconnaissent que les effets hémodynamiques jouent un rôle clé dans la formation, la croissance, et la rupture des anévrismes intracrâniens. Cependant, les procédures expérimentales pour mieux comprendre les caractéristiques de l’écoulement du sang dans l’anévrisme sont encore difficiles à réaliser. Avec le développement de techniques des images du système vasculaire cérébral, il a été possible d’obtenir la géométrie des anévrismes, donc des méthodes numériques ont commencé à être utilisées pour la solution de l’écoulement dans les anévrismes, et alors plusieurs recherches ont étudié l’influence des variables biologiques et hémodynamiques sur la rupture de l’anévrisme. Cependant, ce n’est que dans la dernière décennie que l’influence de l’interaction fluide-structure, due à la flexibilité de la paroi de l’artère, sur ces variables a été étudiée. Dans ce contexte et à l’aide de géométries d’anévri... (Résumé complet accès életronique ci-dessous) / Mestre
199

Hemodynamic changes in intracranial aneurysms due to stent-induced vascular remodeling /

Santos, Gabriel Bertacco dos. January 2018 (has links)
Orientador: José Luiz Gasche / Resumo: Originalmente, stents foram projetados para agir como barreiras mecânicas, impedindo a herniação de coils para a artéria-mãe. Recentemente, estudos mostraram que a atual geração de stents intracranianos auto-expansíveis altera a geometria local das artérias: um fenômeno com efeitos hemodinâmicos em parte incompreendidos. Nós realizamos simulações numéricas para avaliar a influência da remodelagem arterial induzida por stent sobre a hemodinâmica em aneurismas intracranianos. As simulações foram realizadas utilizando o software open-source OpenFOAM. O sangue foi modelado como fluido Newtoniano incompressível e as paredes arteriais foram consideradas rígidas. Para quantificar as alterações hemodinâmicas, avaliamos os parâmetros wall shear stress, WSS, e oscillatory shear index, OSI. Quatro geometrias reais de aneurismas intracranianos em bifurcações foram utilizadas. Em um aneurisma na bifurcação da artéria comunicante anterior (ACoA), um stent foi implantando, levando ao endireitamento das artérias que o receberam. Após o procedimento, os níveis de WSS e OSI aumentaram aproximadamente 60% e 25%, respectivamente. Em dois aneurismas em bifurcações da artéria cerebral média (MCA), dois stents foram implantados em uma configuração em “Y”, resultando em um endireitamento de ambas as artérias-filhas. O WSS máximo na superfície do aneurisma aumentou aproximadamente 5% em um dos casos e 22% no outro. Em outro aneurisma em uma bifurcação da MCA, um stent foi implantado, resultando no en... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Stents were first designed to act as mechanical barriers, preventing coil herniation into the parent artery. The current generation of self-expanding intracranial stents has recently been shown to change the local vascular geometry, a phenomenon with unclear hemodynamic effects. We carried out numerical simulations to assess the role of stent-induced vascular remodeling in modifying intraaneurysmal hemodynamics. Simulations were performed using the open-source software OpenFOAM. Blood was assumed to behave as an incompressible Newtonian fluid; vessel walls were assumed to be rigid. Wall shear stress, WSS, and oscillatory shear index, OSI, were evaluated to quantify the hemodynamic changes in the aneurysm sac. Four pre- and post-stent patient-specific geometries of intracranial bifurcation aneurysm were used. In one aneurysm at the anterior communicating artery (ACoA) bifurcation, a single stent was deployed, resulting in straightening of the host vessels. After stenting, WSS and OSI increased by approximately 60% and 25%, respectively. In two aneurysms at middle cerebral artery (MCA) bifurcations, two stents in a “Y” configuration were deployed, resulting in straightening of both daughter arteries. The maximum WSS on the aneurysm surface increased by approximately 5% in one case and 22% in the other. In another aneurysm at a bifurcation of the MCA, a single stent was deployed, resulting in straightening of the host vessels. After stenting, WSS and OSI reduced by approximately... (Complete abstract click electronic access below) / Mestre
200

Comparação entre diferentes sequências de ressonância magnética na detecção de calcificações em pacientes portadores de neurocisticercose / Comparison between different magnetic resonance sequences in the detection of calcifications in patients with neurocysticercosis

Gislaine Cristina Lopes Machado Porto 06 April 2018 (has links)
Introdução: Neurocisticercose (NCC) é a principal causa evitável de epilepsia adquirida no mundo. NCC, além de ser, a doença parasitária mais comum do SNC, representa um importante problema de saúde pública, especialmente em países em desenvolvimento. Estudos de neuroimagem são cruciais no diagnóstico e planejamento terapêutico da NCC. Apesar da ressonância magnética (RM) fornecer maior número e detalhe de informações sobre a doença, a tomografia computadorizada (TC) ainda é o método mais sensível na detecção de calcificação intracraniana, o achado radiológico mais comum da NCC. Objetivo: Comparar performance das sequências de RM ponderadas em suscetibilidade magnética na identificação de calcificações intracranianas em pacientes com NCC. Métodos: Estudo prospectivo, unicêntrico, no qual 57 indivíduos foram submetidos a TC e RM de crânio. Todos os indivíduos foram provenientes do Ambulatório de Doenças Infecciosas do Departamento de Neurologia do Hospital das Clínicas - Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), com diagnóstico confirmado de NCC. O protocolo de RM incluiu uma sequência convencional 2D gradiente eco (2D-GRE) e duas relativamente novas sequências de suscetibilidade magnética: susceptibilityweighted imaging (SWI) e principles of echo shifting with a train of observations (PRESTO). A TC foi considerada método padrão de referência. Dois neurorradiologistas, cegos para os dados clínicos e demais achados radiológicos, analisaram independentemente as sequências 2D-GRE, SWI e PRESTO quanto à presença, número e localizações de calcificações intracranianas atribuídas a NCC. Resultados: Foram identificadas, pela TC, 739 lesões calcificadas relacionadas a NCC em 50 dos 57 indivíduos incluídos no estudo. A média de lesões calcificadas por paciente foi de 12,9 (± 19,8). A médias de lesões encontradas pelas sequências de suscetibilidade magnética, obtido através da média dos resultados dos observadores, foi de 10,8 (± 17,5) para PRESTO, 10,6 (± 17,3) para SWI e 8,3 (± 13,6) para 2D-GRE. Neste quesito não houve diferença estaticamente significativa entre PRESTO e SWI (p = 0,359) e ambos foram superiores a 2D-GRE (p < 0,05). A concordância foi fraca a moderada, provavelmente devido ao alto número de lesões falso-positivas encontradas (490), das quais 53,9% representavam lesões relacionadas a NCC em estágios não calcificados. A sensibilidade e especificidade das sequências estudadas em identificar corretamente indivíduos com NCC em estágio calcificado foi respectivamente de 85% e 100% para 2D-GRE, 90% e 100% para SWI e 93% e 100% para PRESTO. Conclusão: As sequências SWI, PRESTO e 2D-GRE apresentam boa sensibilidade na identificação de lesões calcificadas em pacientes com NCC. As sequências SWI e PRESTO tiveram melhor performance do que 2D-GRE. Todas as sequências estudadas mostrarem-se apropriadas para identificar indivíduos com NCC no estágio de calcificação. Sequências ponderadas em suscetibilidade magnética podem ajudar no entendimento da história natural, fisiopatologia e achados de imagem da NCC / Background: Neurocysticercosis (NCC) is the main preventable cause of acquired epilepsy. NCC, besides being the most common parasitic disease of the CNS, is an important public health problem, mainly in developing countries. Neuroimaging studies are crucial in the diagnosis and therapeutic planning of NCC. Although magnetic resonance imaging (MRI) provides countless and more detailed information about the disease, computed tomography (CT) is still the most sensitive method for detecting intracranial calcification, the most common radiological finding of NCC. Purpose: To compare the diagnostic performance of susceptibility-weighted MRI sequences in identification of intracranial calcifications in patients with NCC. Methods: A prospective study with 57 subjects who underwent CT and MRI of the brain. All individuals came from Department of Neurology of the Hospital das Clínicas - Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP), with a stablished diagnosis of NCC. The MRI protocol included a conventional 2D gradient echo sequence (2D-GRE) and two relatively new susceptibility-weighted sequences: susceptibility-weighted imaging (SWI) and principles of echo shifting with a train of observations (PRESTO). CT was considered the standard reference method. Two neuroradiologists, blinded to clinical data and other radiological findings, independently analyzed the 2D-GRE, SWI and PRESTO sequences on behalf to presence, number and sites of intracranial calcifications attributed to NCC. Results: A total of 739 NCC-related calcified lesions were identified by CT in 50 of the 57 subjects included in the study. The mean number of calcified lesions per patient was 12.9 (± 19.8). The mean number of lesions found by the susceptibility-weighted MRI sequences, obtained through the mean of the observers\' results, was 10.8 (± 17.5) for PRESTO, 10.6 (± 17.3) for SWI and 8.3 (± 13.6) for 2D-GRE. There was no statistically significant difference between PRESTO and SWI (p = 0.359) and both were superior to 2D-GRE (p < 0.05). The concordance was weak to moderate, probably due to the high number of false-positive lesions found (490), of which 53.9% represented NCC-related lesions in non-calcified stages. The sensitivity and specificity of the sequences studied in correctly identifying individuals with calcified NCC were 85% and 100% respectively for 2D-GRE, 90% and 100% for SWI and 93% and 100% for PRESTO. Conclusion: SWI, PRESTO and 2D-GRE sequences have good sensitivity in the identification of calcified lesions in patients with NCC. SWI and PRESTO performed better than 2DGRE. All sequences studied are suitable for identifying individuals with NCC in the calcified stage. The new susceptibility-weighted MRI sequences may help in understanding the natural history, pathophysiology and imaging findings of NCC

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