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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.
131

Modelo anatômico de ventriculomegalia para treinamento neuroendoscópico / Ventriculomegaly anatomical models for neuroendoscopy training

Ferreira, Christian Diniz 28 May 2015 (has links)
OBJETIVO: Desenvolver peças anatômicas que simulem uma condição real de ventriculomegalia para serem utilizadas como uma ferramenta no treinamento dos neurocirurgiões nas técnicas de neuroendoscopia e viabilizar estudo anatômico dos ventrículos. MÉTODO: Foram utilizadas vinte peças anatômicas de encéfalo de cadáveres de indigentes, com a aprovação do Comitê de Ética em pesquisa da FMUSP sob o número 046/10. As peças foram retiradas da base do crânio com a persistência da superfície óssea (parte da calvária) para serem submetidas aos seguintes procedimentos: canulação do IV ventrículo por meio da abertura mediana do IV ventrículo (forame de Magendie); tomografias pré-experimento e injeção de água destilada no sistema ventricular. A água injetada estava à temperatura ambiente e os cérebros foram resfriados até 4º C e, após 12 horas, foram congelados a uma temperatura de 0º C (no estado sólido) por 24 horas. Esses procedimentos foram realizados na frequência de três vezes. Após o experimento, foram realizadas tomografias pós-experimento e procedimentos neuroendoscópicos ventriculares. Foram excluídos encéfalos com lesões traumáticas ou antecedentes de enfermidades transmissíveis. Não foram critérios de exclusão o sexo e a idade. Foram avaliadas, nas imagens tomográficas, a variação pré e pós-experimento dos seguintes parâmetros: coeficiente corno frontal/diâmetro interno; índice de Evan; e tamanho do corno temporal. As análises estatísticas foram realizadas no programa SPSS (Statistical Package for the Social Sciences) versão 13, para ambos os grupos. RESULTADOS: A avaliação da relação Corno frontal/Diâmetro interno, antes e pós-experimento apresentou média de 11,98% e 19,46%, respectivamente. Estudo estatístico (t Student) mostrou diferença estatística (t= -5142, gl =19; p < 0,01). O Índice de Evan também apresentou diferença significativa (t = -5,172, gl = 9; p < 0,01) entre os resultados antes (média de 10,86%) e após experimento (média de 18,35%). A análise do tamanho do corno temporal mostrou diferença significativa entre os grupos antes e depois do experimento (t = -2,297, gl = 9; p< 0,01), indicando que o tamanho mediano do Corno Temporal é maior após o experimento (média de 2,65cm). CONCLUSÕES: A exploração das características físico-químicas anômalas da molécula da água pode nos fornecer um bom mecanismo expansor de cavidades ventriculares para a indução de ventriculomegalia em uma peça anatômica de encéfalo, em que o endoscópio poderá ser introduzido pelas vias habituais, podendo, assim, realizar observação anatômica e simular o procedimento cirúrgico com a mesma sensibilidade tátil que irá encontrar no procedimento real / PURPOSE: To develop anatomical models which simulate real conditions of ventriculomegaly and to use them as tools to train neuroendoscopic techniques and allow the study of the ventricles. METHODS: A total of twenty brains, with the approval of the Ethics in Research Committee from FMUSP (046/10) were used to perform this research. The brains were separated from the skull base, but keeping part of the calvaria, and then underwent the following procedures: cannulation of the fourth ventricle through the median open of the fourth ventricle (foramen of Magendie); CT scans performed before the experiment; and then injection of distilled water into the ventricular system. The water was injected at room temperature, and then the brains were cooled to 4ºC. After 12 hours, they were then frozen at 0ºC for 24 hours.These procedures were repeated three times. After the experiment,CT scans were performed after the injections and neuroendoscopic procedures. Brains, which had traumatic injuries or history of infectious diseases, were excluded. Gender and age were not exclusion criteria. The statistical analysis was performed with the SPSS program (Statistical Package for the Social Sciences) version 13, for both groups. To assess the variation of the frontal horn (FH)/internal diameter (ID) coefficient, such as Evan\'s index\'s variation, and to analyze the temporal horn (TH) size, thet-Student test was used. RESULTS: The results of the t-Student test showed that the FH/ID, with an average of 11.98% before the experiment, had significant difference (t = -5.142, gl = 19; p < 0.01) after the experiment, with an average of19.46%. The Evan\'s index also showed a significant difference (t = -5.172, gl = 9; p < 0,01) with an initial average of 10.86% and a final average of 18.35%. The analysis of the temporal horn size showed a significant difference between the size before and after the experiment (t = -2.297, gl = 9; p < 0.01), indicating the significant increase of the temporal horn (with an initial average of 0.02cm and a final average of 2.65cm). CONCLUSIONS: The use of the anomalous physical and chemical characteristics of water can provide us with a good expanding mechanism of the ventricular system, creating ventriculomegaly in anatomical models, allowing the endoscope to be introduced by the usual approaches, to perform anatomical observation, and to simulate a surgical procedure with the same sensitivity of a real procedure
132

Investigação de variação do número de cópias em fetos portadores de ventriculomegalia e malformação Dandy Walker / Investigation of variation of the number of copies in fetuses with ventriculomegaly and malformation Dandy Walker

Cibele Diedrichs 08 November 2017 (has links)
INTRODUÇÃO: A ventriculomegalia é a malformação congênita de sistema nervoso central (SNC) mais prevalente, e a malformação Dandy Walker (apesar de menos prevalente) é, assim como a ventriculomegalia, uma doença com um importante impacto pré e pós-natal na morbidade e mortalidade fetal. A etiologia dessas patologias é heterogênea e o fator genético está entre as principais causas. A técnica mais usada no período pré-natal para rastreamento genético é o cariótipo por banda G; contudo esta técnica não revela todas as anormalidades genéticas. Portanto, em fetos com alteração morfológica ultrassonográfica detectada e cariotipagem tradicional normal, o estudo molecular pode ser oferecido para uma investigação etiológica e aconselhamento genético. OBJETIVO: Este estudo visa investigar a presença de CNVs (do inglês, copy number variations) utilizando cariotipagem por array em amostras de DNA obtidas de fetos portadores de ventriculomegalia (VM) ou Malformação de Dandy-Walker (MDW), com resultado de cariótipo clássico normal. MÉTODO: Foram selecionadas 29 gestantes com fetos portadores de VM e MDW. Das 29 amostras colhidas, 2 foram excluídas devido PCR positivo para infecções congênitas e outras 3 excluídas devido cariótipo por banda G apresentando anomalias cromossômica. Um total de 24 fetos foram incluídos no estudo, sendo 19 portadores de ventriculomegalia e 5 casos de MDW diagnosticados na ultrassonografia pré-natal. Todos os casos apresentavam cariótipo por banda G normal e PCR negativo para infecções congênitas no líquido amniótico. O DNA fetal foi extraído do cordão umbilical através da cordocentese entre 20 e 34 semanas e foi analisado pelo SNP array. As CNVs encontradas foram comparadas com banco de dados e literatura e posteriormente classificadas patogênicas, significado clínico incerto (VUS; do inglês variation of uncertain clinical significance) ou benignas. RESULTADOS: Nos 5 fetos com MDW a média da idade gestacional do diagnóstico foi de 26,8 semanas (SD 1,78 semanas). Todos os fetos eram do sexo feminino. Encontradas 6 CNVs. Todas consideradas benignas. Nos 19 fetos portadores de VM, a média do diâmetro no nascimento foi de 29,9 mm (DP 15,21mm). A média da idade gestacional do diagnóstico foi de 27 semanas (DP: 3,41 semanas). O sexo masculino representou 57,8% dos casos e o feminino, 42,1%. Foram encontradas 41 CNVs (22 benignas e 16 VUS) além de 15 eventos de perda de heterozigosidade (LOH). Nenhuma CNV foi considerada patogênica. CONCLUSÃO: Foi possível detectar CNVs utilizando cariotipagem por array em 22, dos 24 casos selecionados de VM e MDW; determinar qual a região cromossômica alterada, além de associar essas regiões com genes envolvidos. Os genes envolvidos foram estudados e comparados com o banco de dados. Contudo para correlacionar os achados ultrassonográficos com os achados citogenômicos encontrados ainda necessitamos de mais estudos acumulativos para enriquecer os bancos de dados existentes e melhorar a assistência pré-natal, diagnóstico e prognóstico dos pacientes portadores de ventriculomegalia e malformação Dandy Walker / BACKGROUND: Ventriculomegaly is the most prevalent congenital central nervous system (CNS) anomalies. Dandy Walker malformation (DWM), although lower prevalent, is, like ventriculomegaly, a disease with a significant prenatal and postnatal impact on fetal morbidity and mortality. The etiology of these pathologies is heterogeneous and the genetic factor is among the main causes. The most used technique in the prenatal period for genetic tracing is the K-band karyotype. However, this technique does not reveal all genetic abnormalities. Therefore, in fetuses with detected ultrasound morphological alteration and normal traditional karyotyping, the molecular study may be offered for an etiological investigation and genetic counseling. OBJECTIVE: To investigate copy number variations (CNVs) using a single nucleotide polymorphism (SNP) array and identify changes in chromosomal regions in fetuses with ventriculomegaly (VM). METHOD: Twenty nine pregnant women with fetuses with ventriculomegaly and DWM were selected. Of the 29 samples collected, 2 were excluded due to positive PCR for congenital infections and another 3 excluded due to G-band karyotype presenting chromosomal abnormalities. A total of 24 fetuses were included in the study, 19 of whom had ventriculomegaly and 5 MDW cases diagnosed on prenatal ultrasonography. All cases presented normal G-band karyotype and negative PCR for congenital infections in the amniotic fluid. The fetal DNA was extracted from the umbilical cord by cordocentesis between 20 and 34 weeks and was analyzed by the SNP array. The CNV were compared with databases and literature and then classified into three groups: pathogenic CNVs, CNVs with uncertain clinical significance (VUS) and benign CNVs. RESULTS: In the 5 fetuses with MDW the mean gestational age of the diagnosis was 26.8 weeks (SD 1.78 weeks). All fetuses were female. Found 6 CNVs. All CNVs considered benign. In the 19 fetuses with MV, the mean of the cerebral ventricle diameter at birth was 29.9 mm (SD 15.21 mm). The mean gestational age of the diagnosis was 27 weeks (SD: 3.41 weeks). The male gender represented 57.8% of the cases and female, 42.1%. We found 41 CNVs (22 benign and 16 VUS) in addition to 15 heterozygosity loss (LOH). No CNV was considered pathogenic. CONCLUSION: It was possible to detect CNVs using array in 22 of the 24 selected cases of VM and DWM; determine the altered chromosomal region, and associate these regions with the genes involved. The genes involved were studied and compared to the database. However, to correlate ultrasonographic findings with the cytogenetic anomalies detected, we still need more cumulative studies to enrich existing databases and improve prenatal care, diagnosis and prognosis of patients with VM and DWM
133

A pilot project exploring the feasibility of enlisting health information & support networks to enable health information seekers, using semantic web middleware

Gardner, Jesse William 27 September 2019 (has links)
My Thesis posits a novel method of utilizing emerging web semantics, through HTML5 markup; to improve experience of Health Information seekers through a framework for creating functional, tailored Health Information Resource Collections potentially hosted by their own Health Information Support Networks; and based upon long-standing principles of online Information Retrieval. Most such organizations have websites, with links to useful Resources. This research exemplifies how to design and to present the Resource Collections as pathfinders to existing online Health Information, adding context to each link, to directly address the needs of each community served. The research appeals to a Needs Analysis process rooted in Everyday Life Information Seeking research methodologies, especially Participatory Action Research. As a pilot project, the Needs Analysis focuses necessarily on the Spina Bifida & Hydrocephalus community – with which the author of the Thesis is intimately familiar as a person living with Hydrocephalus, making the choice of a Participatory Action Research framework ideal – and enlisted just one National (Canada) and one Regional (British Columbia) Association for the same rationale. Results of the Needs Analysis were used to identify necessary Resources, but also to select familiar web tools and technologies for design of the Resource Collection and Resource Cards. At completion, there is a functional Collection of Spina Bifida & Hydrocephalus Resources for researchers, caregivers, or patients with Spina Bifida and/or Hydrocephalus – not limited to members of any organization, but best suited by design to the two through which analysis was done. / Graduate
134

Cerebrospinal Fluid Shunts in Children : Technical Considerations and Treatment of Certain Complications

Arnell, Kai January 2007 (has links)
<p>Ventriculo-peritoneal shunting is the most commonly used method for the treatment of paediatric hydrocephalus. Despite improved shunts and surgical techniques there are still complications. This retrospective study focuses on diagnoses and treatment of shunt malfunction and infections. Cost/benefit of using an adjustable shunt was assessed. Two adjustable cerebrospinal fluid shunts and their compatible antisiphon devices were compared in-vitro.</p><p>In 21 of 46 children the standard shunt was changed to an adjustable one due to over-drainage. Adjustment of the shunt was performed in 73% of the children thereby avoiding surgery in several cases. This was a financial advantage.</p><p>Ascites or an abdominal pseudocyst without infection was detected in eight children due to resorption difficulties. A ventriculo-atrial shunt was inserted for a period of time. In three children it could successfully be reverted to a ventriculo-peritoneal.</p><p>In six children papilloedema was the only sign of shunt dysfunction. At revision the intracranial pressure ranged from 25 to 52 cm H<sub>2</sub>O. Fundoscopic examination in children older than 8 years may detect symptomless shunt malfunction.</p><p>During a 13-year period 39 shunt infections were diagnosed. Skin bacteria were found in 80%. Prolonged and anaerobic cultures increased the detection rate by more than one third. The intraventricular infections were treated with intraventricular and systemic antibiotics resulting in quick sterilisation. No relapses were encountered. In five older children with distal catheter infection <i>Propionibacterium acne</i> was found. These were treated with intravenous antibiotics and exchanging of the shunt system.</p><p>Strata NSC<sup>TM</sup> and Codman Hakim<sup>TM</sup> worked according to the manufacturers except at the lowest setting. The resistance was below and in the lower range of the physiological one respectively. The antisiphon device of Strata shunt had to be placed in line with shunt to function properly. </p>
135

Cerebrospinal Fluid Shunts in Children : Technical Considerations and Treatment of Certain Complications

Arnell, Kai January 2007 (has links)
Ventriculo-peritoneal shunting is the most commonly used method for the treatment of paediatric hydrocephalus. Despite improved shunts and surgical techniques there are still complications. This retrospective study focuses on diagnoses and treatment of shunt malfunction and infections. Cost/benefit of using an adjustable shunt was assessed. Two adjustable cerebrospinal fluid shunts and their compatible antisiphon devices were compared in-vitro. In 21 of 46 children the standard shunt was changed to an adjustable one due to over-drainage. Adjustment of the shunt was performed in 73% of the children thereby avoiding surgery in several cases. This was a financial advantage. Ascites or an abdominal pseudocyst without infection was detected in eight children due to resorption difficulties. A ventriculo-atrial shunt was inserted for a period of time. In three children it could successfully be reverted to a ventriculo-peritoneal. In six children papilloedema was the only sign of shunt dysfunction. At revision the intracranial pressure ranged from 25 to 52 cm H2O. Fundoscopic examination in children older than 8 years may detect symptomless shunt malfunction. During a 13-year period 39 shunt infections were diagnosed. Skin bacteria were found in 80%. Prolonged and anaerobic cultures increased the detection rate by more than one third. The intraventricular infections were treated with intraventricular and systemic antibiotics resulting in quick sterilisation. No relapses were encountered. In five older children with distal catheter infection Propionibacterium acne was found. These were treated with intravenous antibiotics and exchanging of the shunt system. Strata NSCTM and Codman HakimTM worked according to the manufacturers except at the lowest setting. The resistance was below and in the lower range of the physiological one respectively. The antisiphon device of Strata shunt had to be placed in line with shunt to function properly.
136

Analysis of ICP pulsatility and CSF dynamics : the pulsatility curve and effects of postural changes, with implications for idiopathic normal pressure hydrocephalus / Analys av ICP-pulsationer och CSF-dynamik : pulsationskurvan och effekter av ändrad kroppsposition, med implikationer för idiopatisk normaltryckshydrocefalus

Qvarlander, Sara January 2013 (has links)
The volume defined by the rigid cranium is shared by the brain, blood and cerebrospinal fluid (CSF). With every heartbeat the arterial blood volume briefly increases and venous blood and CSF are forced out of the cranium, leading to pulsatility in CSF flow and intracranial pressure (ICP). Altered CSF pulsatility has been linked to idiopathic normal pressure hydrocephalus (INPH), which involves enlarged cerebral ventricles and symptoms of gait/balance disturbance, cognitive decline and urinary incontinence that may be improved by implantation of a shunt. The overall aim of this thesis was to investigate the fluid dynamics of the CSF system, with a focus on pulsatility, and how they relate to INPH pathophysiology and treatment. Mathematical modelling was applied to data from infusion tests, where the ICP response to CSF volume manipulation is measured, to analyse the relationship between mean ICP and ICP pulse amplitude (AMP) before and after shunt surgery in INPH (paper I-II). The observed relationship, designated the pulsatility curve, was found to be constant at low ICP and linear at high ICP, corresponding to a shift from constant to ICP dependent compliance (paper I). Shunt surgery did not affect the pulsatility curve, but shifted baseline ICP and AMP along the curve towards lower values. Patients who improved in gait after surgery had significantly larger AMP reduction than those who did not, while ICP reduction was similar, suggesting that improving patients had baseline ICP in the linear zone of the curve before surgery. Use of this phenomenon for outcome prediction was promising (paper II). The fluid dynamics of an empirically derived pulsatility-based predictive infusion test for INPH was also investigated, with results showing strong influence from compliance (paper III). Clinical ICP data at different body postures was used to evaluate three models describing postural effects on ICP. ICP decreased in upright positions, whereas AMP increased. The model describing the postural effects based on hydrostatic changes in the venous system, including effects of collapse of the jugular veins in the upright position, accurately predicted the measured ICP (paper IV). Cerebral blood flow and CSF flow in the aqueduct and at the cervical level was measured with phase contrast magnetic resonance imaging, and compared between healthy elderly and INPH (paper V). Cerebral blood flow and CSF flow at the cervical level were similar in INPH patients and healthy elderly, whereas aqueductal CSF flow differed significantly. The pulsatility in the aqueduct flow was increased, and there was more variation in the net flow in INPH, but the mean net flow was normal, i.e. directed from the ventricles to the subarachnoid space (paper V). In conclusion, this thesis introduced the concept of pulsatility curve analysis, and provided evidence that pulsatility and compliance are important aspects for successful shunt treatment and outcome prediction in INPH. It was further confirmed that enhanced pulsatility of aqueduct CSF flow was the most distinct effect of INPH pathophysiology on cerebral blood flow and CSF flow. A new model describing postural and hydrostatic effects on ICP was presented, and the feasibility and potential importance of measuring ICP in the upright position in INPH was demonstrated. / <p>Forskningsfinansiär: </p><p>European Union, ERDF: Objective 2, Northern Sweden (grant no. 158715-CMTF). </p>
137

Measurements in Idiopathic Normal Pressure Hydrocephalus : Computerized neuropsychological test battery and intracranial pulse waves

Behrens, Anders January 2014 (has links)
Idiopathic Normal Pressure Hydrocephalus (INPH) is a condition affecting gait, cognition and continence. Radiological examination reveals enlarged ventricles of the brain. A shunt that drains CSF from the ventricles to the abdomen often improves the symptoms. Much research on INPH has been focused on identifying tests that predict the outcome after shunt surgery. As part of this quest, there are attempts to find measurement methods of intracranial parameters that are valid, reliable, tolerable and safe for patients. Today's technologies for intracranial pressure (ICP) measurement are invasive, often requiring a burr-hole in the skull. Recently, a method for non-invasive ICP measurements was suggested: the Pulsatile Index (PI) calculated from transcranial Doppler data assessed from the middle cerebral artery. In this thesis the relation between PI and ICP was explored in INPH patients during controlled ICP regulation by lumbar infusion. The confidence interval for predicted ICP, based on measured PI was too large for the method to be of clinical utility. In the quest for better predictive tests for shunt success in INPH, recent studies have shown promising results with criteria based on cardiac related ICP wave amplitudes. The brain ventricular system, and the fluid surrounding the spinal cord are in contact. In this thesis it was shown that ICP waves could be measured via lumbar subarachnoid space, with a slight underestimation. One of the cardinal symptoms of hydrocephalus is cognitive impairment. Neuropsychological studies have demonstrated cognitive tests that are impaired and improve after shunt surgery in INPH patients. However, there is currently no standardized test battery and different studies use different tests. In response, in this thesis a fully automated computerized neuropsychological test battery was developed. The validity, reliability, responsiveness to improvement after shunt surgery and feasibility for testing INPH patients was demonstrated. It was also demonstrated that INPH patients were impaired in all subtests, compared to healthy elderly.
138

Η προγνωστική αξία της προσωρινής εξωτερικής οσφυικής παροχέτευσης με βαλβίδα μέσης πίεσης, στον υδροκέφαλο φυσιολογικής πίεσης / The predictive value of a temporary external lumbar drainage with medium pressure valve in normal pressure hydrocephalus

Παναγιωτόπουλος, Βασίλειος 26 June 2007 (has links)
Σποραδικές μελέτες περιγράφουν την προσωρινή εξωτερική οσφυϊκή παροχέτευση του ΕΝΥ, ως μία δοκιμασία υψηλής ακριβείας όσον αφορά στην πρόβλεψη του κλινικού αποτελέσματος μετά από κοιλιοπεριτοναϊκή παροχέτευση στους ασθενείς με ΥΦΠ. Παρόλα αυτά, σε μία πιο πρόσφατη μελέτη από τους Walchenbach και συνεργάτες, εκτιμήθηκε ότι η θετική προγνωστική αξία της ΕΟΠ ήταν υψηλή, ενώ η αρνητική χαμηλή. Δια ταύτα, πραγματοποιήσαμε μία προοπτική μελέτη με σκοπό να εκτιμήσουμε την προγνωστική αξία μιάς προσωρινής εξωτερικής οσφυικής παροχέτευσης (ΕΟΠ), η οποία ρυθμίζει την εκροή ΕΝΥ μέσω μιάς βαλβίδας μέσης πίεσης μονόδρομης ροής, σε ασθενείς με υδροκέφαλο φυσιολογικής πίεσης (ΥΦΠ). Είκοσι επτά 27 ασθενείς με ΥΦΠ εισήχθησαν στη Νευροχειρουργική Κλινική του ΠΓΝΠ και υπεβλήθησαν σε τοποθέτηση προσωρινής εξωτερικής οσφυικής παροχέτευσης (ΕΟΠ), η οποία ρυθμίζει την εκροή ΕΝΥ μέσω μιάς βαλβίδας μέσης πίεσης, για 5 ημέρες. 22 ασθενείς υπεβλήθησαν τελικά σε κοιλιοπεριτοναϊκή παροχέτευση με βαλβίδα μέσης πίεσης, βασιζόμενοι σε κλινικά και ακτινολογικά κριτήρια, ανεξαρτήτως του αποτελέσματος της ΕΟΠ. Κλινική εκτίμηση των διαταραχών της βάδισης, της ούρησης και της νόησης, όπως επίσης και ακτινολογική εκτίμηση, πραγματοποιήθηκε προ και μετά την δοκιμασία της ΕΟΠ καθώς και 3 μήνες μετά την ΚΠΠ. Είκοσι δύο 22 ασθενείς υπεβλήθησαν τελικά σε κοιλιοπεριτοναϊκή παροχέτευση και πληρούσαν τα κριτήρια για να συμπεριληφθούν τελικά στη μελέτη. Χρησιμοποιώντας ένα εγκεκριμένο σύστημα βαθμολόγησης, η συνολική βελτίωση μετά τη δοκιμασία ΕΟΠ συσχετιζόταν καλά με τη βελτίωση 3 μήνες μετά την μόνιμη ΚΠΠ. (Spearman’ s rho = 0,462, p=0,03). Όταν θεωρήσαμε κάθε βαθμό βελτίωσης ως θετική ανταπόκριση, η δοκιμασία ΕΟΠ-βαλβίδας μέσης πίεσης είχε υψηλή θετική προγνωστική αξία για κάθε μία ανεξάρτητη κλινική παράμετρο (διαταραχές της βάδισης 94%, 95% CI 71%-100%, ακράτεια στην ούρηση 100%, 95% CI 66%-100%, διαταραχές της νόησης 100%, 95% CI 66-100%), ενώ η αρνητική προγνωστική αξία ήταν χαμηλή (<50%) εκτός από τις διαταραχές της νόησης (85%, 95% CI 55%-98%). Η ανωτέρω μελέτη συμπεραίνει ότι η δοκιμασία της ΕΟΠ-βαλβίδας μέσης πίεσης, θα πρέπει να θεωρείται ένα αξιόπιστο κριτήριο για την προεγχειρητική επιλογή υδροκεφαλικών ασθενών φυσιολογικής πίεσης που βελτιώνονται κλινικά μετά την τοποθέτηση ΚΠΠ. Σε περίπτωση αρνητικής δοκιμασίας ΕΟΠ-βαλβίδας μέσης πίεσης, θα πρέπει να διενεργείται περαιτέρω διερεύνηση με επιπρόσθετες διαγνωστικές δοκιμασίες. / Although sporadic studies have described temporary external cerebrospinal fluid (CSF) lumbar drainage as a highly accurate test in predicting the outcome after ventricular shunting in normal pressure hydrocephalus (NPH) patients, a more recent study reports that the positive predictive value of external lumbar drainage (ELD) is high but the negative predictive value is deceptively low. Therefore, we conducted a prospective study in order to evaluate the predictive value of a continuous ELD, with CSF outflow controlled by medium pressure valve, in NPH patients. Twenty-seven patients with presumed NPH were admitted to our department and CSF drainage was carried out by a temporary (ELD), with CSF outflow controlled by medium pressure valve for five days. Twenty-two patients received a ventriculo¬peritoneal shunt with medium pressure valve based upon preoperative clinical and radiographic criteria of NPH, regardless of ELD outcome. Clinical evaluation of gait disturbances, urinary incontinence and mental status, and radiological evaluation with brain CT was performed prior to and after ELD test, as well as three months after shunting. Twenty-two patients were finally shunted and included in this study. In a three-month follow-up, using a previously validated score system, overall improvement after permanent shunting correlated well with improvement after ELD test (Spearman’s rho=0.462, p=0.03). When considering any degree of improvement as a positive response, ELD test yielded high positive predictive values for all individual parameters (gait disturbances 94%, 95% CI 71%-100%, urinary incontinence 100%, 95% CI 66%-100%, and mental status 100%, 95% CI 66%-100%) but negative predictive values were low (<50%) except for cognitive impairment (85%, 95% CI 55%-98%). This study suggests that a positive ELD-valve system test should be considered a reliable criterion for preoperative selection of shunt-responsive NPH patients. In case of a negative ELD-valve system test, further investigation of the presumed NPH patients with additional tests should be performed.
139

Modelo anatômico de ventriculomegalia para treinamento neuroendoscópico / Ventriculomegaly anatomical models for neuroendoscopy training

Christian Diniz Ferreira 28 May 2015 (has links)
OBJETIVO: Desenvolver peças anatômicas que simulem uma condição real de ventriculomegalia para serem utilizadas como uma ferramenta no treinamento dos neurocirurgiões nas técnicas de neuroendoscopia e viabilizar estudo anatômico dos ventrículos. MÉTODO: Foram utilizadas vinte peças anatômicas de encéfalo de cadáveres de indigentes, com a aprovação do Comitê de Ética em pesquisa da FMUSP sob o número 046/10. As peças foram retiradas da base do crânio com a persistência da superfície óssea (parte da calvária) para serem submetidas aos seguintes procedimentos: canulação do IV ventrículo por meio da abertura mediana do IV ventrículo (forame de Magendie); tomografias pré-experimento e injeção de água destilada no sistema ventricular. A água injetada estava à temperatura ambiente e os cérebros foram resfriados até 4º C e, após 12 horas, foram congelados a uma temperatura de 0º C (no estado sólido) por 24 horas. Esses procedimentos foram realizados na frequência de três vezes. Após o experimento, foram realizadas tomografias pós-experimento e procedimentos neuroendoscópicos ventriculares. Foram excluídos encéfalos com lesões traumáticas ou antecedentes de enfermidades transmissíveis. Não foram critérios de exclusão o sexo e a idade. Foram avaliadas, nas imagens tomográficas, a variação pré e pós-experimento dos seguintes parâmetros: coeficiente corno frontal/diâmetro interno; índice de Evan; e tamanho do corno temporal. As análises estatísticas foram realizadas no programa SPSS (Statistical Package for the Social Sciences) versão 13, para ambos os grupos. RESULTADOS: A avaliação da relação Corno frontal/Diâmetro interno, antes e pós-experimento apresentou média de 11,98% e 19,46%, respectivamente. Estudo estatístico (t Student) mostrou diferença estatística (t= -5142, gl =19; p < 0,01). O Índice de Evan também apresentou diferença significativa (t = -5,172, gl = 9; p < 0,01) entre os resultados antes (média de 10,86%) e após experimento (média de 18,35%). A análise do tamanho do corno temporal mostrou diferença significativa entre os grupos antes e depois do experimento (t = -2,297, gl = 9; p< 0,01), indicando que o tamanho mediano do Corno Temporal é maior após o experimento (média de 2,65cm). CONCLUSÕES: A exploração das características físico-químicas anômalas da molécula da água pode nos fornecer um bom mecanismo expansor de cavidades ventriculares para a indução de ventriculomegalia em uma peça anatômica de encéfalo, em que o endoscópio poderá ser introduzido pelas vias habituais, podendo, assim, realizar observação anatômica e simular o procedimento cirúrgico com a mesma sensibilidade tátil que irá encontrar no procedimento real / PURPOSE: To develop anatomical models which simulate real conditions of ventriculomegaly and to use them as tools to train neuroendoscopic techniques and allow the study of the ventricles. METHODS: A total of twenty brains, with the approval of the Ethics in Research Committee from FMUSP (046/10) were used to perform this research. The brains were separated from the skull base, but keeping part of the calvaria, and then underwent the following procedures: cannulation of the fourth ventricle through the median open of the fourth ventricle (foramen of Magendie); CT scans performed before the experiment; and then injection of distilled water into the ventricular system. The water was injected at room temperature, and then the brains were cooled to 4ºC. After 12 hours, they were then frozen at 0ºC for 24 hours.These procedures were repeated three times. After the experiment,CT scans were performed after the injections and neuroendoscopic procedures. Brains, which had traumatic injuries or history of infectious diseases, were excluded. Gender and age were not exclusion criteria. The statistical analysis was performed with the SPSS program (Statistical Package for the Social Sciences) version 13, for both groups. To assess the variation of the frontal horn (FH)/internal diameter (ID) coefficient, such as Evan\'s index\'s variation, and to analyze the temporal horn (TH) size, thet-Student test was used. RESULTS: The results of the t-Student test showed that the FH/ID, with an average of 11.98% before the experiment, had significant difference (t = -5.142, gl = 19; p < 0.01) after the experiment, with an average of19.46%. The Evan\'s index also showed a significant difference (t = -5.172, gl = 9; p < 0,01) with an initial average of 10.86% and a final average of 18.35%. The analysis of the temporal horn size showed a significant difference between the size before and after the experiment (t = -2.297, gl = 9; p < 0.01), indicating the significant increase of the temporal horn (with an initial average of 0.02cm and a final average of 2.65cm). CONCLUSIONS: The use of the anomalous physical and chemical characteristics of water can provide us with a good expanding mechanism of the ventricular system, creating ventriculomegaly in anatomical models, allowing the endoscope to be introduced by the usual approaches, to perform anatomical observation, and to simulate a surgical procedure with the same sensitivity of a real procedure
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Derivação ventriculosinusal retrógrada em lactentes com hidrocefalia após correção de mielomeningocele / Retrograde ventriculosinus shunt in infants with hydrocephalus after treatment of myelomeningocele

Matheus Fernandes de Oliveira 27 March 2017 (has links)
INTRODUÇÃO. Atualmente, o tratamento da hidrocefalia é realizado principalmente através de uma Derivação ventrículo-peritoneal (DVP). Este estudo tem como objetivo descrever a aplicação da derivação ventrículosinusal retrógrada (DVSR) em pacientes com hidrocefalia após o tratamento cirúrgico de mielomeningocele. MÉTODO. Estudo prospectivo, randomizado e controlado. Foram selecionados consecutivamente 9 pacientes com hidrocefalia após correção cirúrgica de mielomeningocele de janeiro de 2010 a janeiro de 2012. Os pacientes foram submetidos à DVSR ou DVP eletiva. Cinco submetidos à DVSR e 4 à DVP, sendo seguidos por 1 ano com realização trimestral de avaliações clínicas, de imagem e aplicação do Doppler transcraniano. RESULTADOS. Os pacientes tratados com DVSR apresentaram desfechos clínicos semelhantes aos do grupo de 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, complicações e desfechos centrados nos pacientes não diferiram entre os grupos. CONCLUSÕES. A técnica cirúrgica da derivação ventrículo-sinusal retrógrada é viável; ela é uma opção alternativa para o tratamento de hidrocefalia / INTRODUCTION. Currently, 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 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. These patients were followed for one year with quarterly clinical and image evaluations and application of transcranial Doppler. RESULTS. Patients treated with RVSS showed clinical outcomes similar to those of VPS group. Doppler showed significant improvement when comparing preoperative to the postoperative period. RVSS group showed significantly higher cephalic perimeter than VPS group. Neuropsychomotor development, complications and subjective outcomes did not differ between groups. CONCLUSIONS. Surgical technique of retrograde ventricle-sinus shunt is viable; it is an alternative option for the treatment of hydrocephalus

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