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1.
BMC Med Res Methodol ; 24(1): 20, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38267888

RESUMO

Systematic reviews are an essential tool in identifying knowledge gaps and synthesizing evidence from in vivo animal research to improve human health. The review process follows an explicit and systematic methodology to minimize bias, but is not immune to biases or methodological flaws. Pre-registering a systematic review protocol has several benefits, including avoiding unplanned duplication of reviews, reducing reporting biases, and providing structure throughout the review process. It also helps to align the opinions of review team members and can shield researchers from post-hoc critique. PROSPERO4animals is the international prospective register of systematic reviews (PROSPERO) for the preregistration of systematic review of animal studies. As administrators, here we provide 10 tips to facilitate pre-registration in PROSPERO4animals. These tips address common difficulties that both beginners and experienced researchers may face when pre-registering their systematic review protocols. This article aims to help authors write and register a detailed systematic review protocol on PROSPERO4animals.


Assuntos
Revisões Sistemáticas como Assunto , Animais , Humanos , Pesquisadores
2.
BMC Neurol ; 24(1): 68, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368355

RESUMO

BACKGROUND: Ruptured intracranial aneurysms resulting in subarachnoid haemorrhage can be treated by open surgical or endovascular treatment. Despite multiple previous studies, uncertainties on the optimal treatment practice still exists. The resulting treatment variation may result in a variable, potentially worse, patient outcome. To better inform future treatment strategies, this study aims to identify the effectiveness of different treatment strategies in patients with ruptured intracranial aneurysms by investigating long-term functional outcome, complications and cost-effectiveness. An explorative analysis of the diagnostic and prognostic value of radiological imaging will also be performed. METHODS: This multi-centre observational prospective cohort study will have a follow-up of 10 years. A total of 880 adult patients with a subarachnoid haemorrhage caused by a ruptured intracranial aneurysm will be included. Calculation of sample size (N = 880) was performed to show non-inferiority of clip-reconstruction compared to endovascular treatment on 1 year outcome, assessed by using the ordinal modified Rankin Scale. The primary endpoint is the modified Rankin Scale score and mortality at 1 year after the initial subarachnoid haemorrhage. Patients will receive 'non-experimental' regular care during their hospital stay. For this study, health questionnaires and functional outcome will be assessed at baseline, before discharge and at follow-up visits. DISCUSSION: Despite the major healthcare and societal burden, the optimal treatment strategy for patients with subarachnoid haemorrhage caused by ruptured intracranial aneurysms is yet to be determined. Findings of this comparative effectiveness study, in which in-between centre variation in practice and patient outcome are investigated, will provide evidence on the effectiveness of treatment strategies, hopefully contributing to future high value treatment standardisation. TRIAL REGISTRATION NUMBER: NCT05851989 DATE OF REGISTRATION: May 10th, 2023.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Adulto , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/cirurgia , Estudos Prospectivos , Embolização Terapêutica/métodos , Prognóstico , Resultado do Tratamento , Aneurisma Roto/complicações , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/cirurgia , Estudos Observacionais como Assunto , Estudos Multicêntricos como Assunto
3.
Acta Neurochir (Wien) ; 165(7): 1869-1879, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37289301

RESUMO

BACKGROUND: The Woven Endobridge (WEB) is designed to treat intracranial wide-neck bifurcation aneurysms, preventing subarachnoid hemorrhage. The translational value of animal models used for WEB device testing is unknown. With this systematic review, we aim to identify the existing animal models used in testing the WEB device and compare the efficacy and safety outcomes to those of prospective clinical studies. METHODS: This study was funded by ZonMw: project number 114024133. A comprehensive search was performed in PubMed and in EMBASE via the Ovid interface. The following exclusion criteria were used: 1) not an original full-length research paper, 2) not an in vivo animal study or a human study, 3) no WEB implantation, 4) if in humans: not a prospective study. The SYRCLE risk of bias tool (animal studies) and the Newcastle-Ottawa quality assessment scale for cohort studies (clinical studies) were used to assess risks of bias. A narrative synthesis was performed. RESULTS: Six animal studies and 17 clinical studies met the inclusion criteria. The rabbit elastase aneurysm model was the only animal model used to assess WEB device performance. Safety outcomes were never reported in animal studies. Efficacy outcomes were more heterogeneous in animal studies than in clinical studies, which could be due to limited external validity of the animal models in terms of aneurysm induction and dimensions. Both animal and clinical studies were predominantly single-arm studies, and were at unclear risk of several types of bias. CONCLUSIONS: The rabbit elastase aneurysm model was the only pre-clinical animal model used to assess WEB device performance. Safety outcomes were not evaluated in animal studies and could therefore not be compared to clinical outcomes. Efficacy outcomes were more heterogeneous in animal studies than in clinical studies. Future research should focus on improving methodology and reporting in order to draw accurate conclusions on the performance of the WEB device.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Animais , Humanos , Coelhos , Resultado do Tratamento , Estudos Prospectivos , Procedimentos Endovasculares/métodos , Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Modelos Animais , Estudos Retrospectivos
4.
Neurosurg Focus ; 52(3): E2, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35231892

RESUMO

OBJECTIVE: Delayed cerebral ischemia (DCI) contributes to morbidity and mortality after aneurysmal subarachnoid hemorrhage (aSAH). Continuous improvement in the management of these patients, such as neurocritical care and aneurysm repair, may decrease the prevalence of DCI. In this study, the authors aimed to investigate potential time trends in the prevalence of DCI in clinical studies of DCI within the last 20 years. METHODS: PubMed, Embase, and the Cochrane library were searched from 2000 to 2020. Randomized controlled trials that reported clinical (and radiological) DCI in patients with aSAH who were randomized to a control group receiving standard care were included. DCI prevalence was estimated by means of random-effects meta-analysis, and subgroup analyses were performed for the DCI sum score, Fisher grade, clinical grade on admission, and aneurysm treatment method. Time trends were evaluated by meta-regression. RESULTS: The search strategy yielded 5931 records, of which 58 randomized controlled trials were included. A total of 4424 patients in the control arm were included. The overall prevalence of DCI was 0.29 (95% CI 0.26-0.32). The event rate for prevalence of DCI among the high-quality studies was 0.30 (95% CI 0.25-0.34) and did not decrease over time (0.25% decline per year; 95% CI -2.49% to 1.99%, p = 0.819). DCI prevalence was higher in studies that included only higher clinical or Fisher grades, and in studies that included only clipping as the treatment modality. CONCLUSIONS: Overall DCI prevalence in patients with aSAH was 0.29 (95% CI 0.26-0.32) and did not decrease over time in the control groups of the included randomized controlled trials.


Assuntos
Isquemia Encefálica , Hemorragia Subaracnóidea , Vasoespasmo Intracraniano , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/etiologia , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/cirurgia , Fatores de Tempo
5.
Acta Neurochir (Wien) ; 164(11): 2867-2873, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36149501

RESUMO

PURPOSE: Hydrocephalus requiring permanent CSF shunting after aneurysmal subarachnoid hemorrhage (aSAH) is frequent. It is unknown which type of valve is optimal. This study evaluates if the revision rate of gravitational differential pressure valves (G-DPVs, GAV® system (B Braun)) (G-DPV) is comparable to adjustable pressure valves (Codman Medos Hakim) (APV) in the treatment of post-aSAH hydrocephalus. METHODS: The use of a gravitational differential pressure valve is placed in direct comparison with an adjustable pressure valve system. A retrospective chart review is performed to compare the revision rates for the two valve systems. RESULTS: Within the registry from Radboud University Medical Center, 641 patients with a SAH could be identified from 1 January 2013 until 1 January 2019, whereas at the Heinrich Heine University, 617 patients were identified, totaling 1258 patients who suffered from aSAH. At Radboud University Medical Center, a gravitational differential pressure valve is used, whereas at the Heinrich Heine University, an adjustable pressure valve system is used. One hundred sixty-six (13%) patients required permanent ventricular peritoneal or atrial shunting. Shunt dysfunction occurred in 36 patients: 13 patients of the 53 (25%) of the gravitational shunt cohort, and in 23 of the 113 (20%) patients with an adjustable shunt (p = 0.54). Revision was performed at a mean time of 3.2 months after implantation with the gravitational system and 8.2 months with the adjustable shunt system. Combined rates of over- and underdrainage leading to revision were 7.5% (4/53) for the gravitational and 3.5% (4/113) for the adjustable valve system (p = 0 .27). CONCLUSION: The current study does not show a benefit of a gravitational pressure valve (GAV® system) over an adjustable pressure valve (CODMAN ® HAKIM®) in the treatment of post-aSAH hydrocephalus. The overall need for revision is high and warrants further improvements in care.


Assuntos
Hidrocefalia , Hemorragia Subaracnóidea , Humanos , Estudos Retrospectivos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/cirurgia , Complicações Pós-Operatórias/cirurgia , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Gravitação , Derivações do Líquido Cefalorraquidiano , Derivação Ventriculoperitoneal
6.
Acta Neurochir (Wien) ; 163(4): 1143-1151, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33387044

RESUMO

BACKGROUND: The need for external cerebrospinal fluid (CSF) drains in aneurysmal subarachnoid haemorrhage (aSAH) patients is common and might lead to additional complications. OBJECTIVE: A relation between the presence of an external CSF drain and complication risk is investigated. METHODS: A prospective complication registry was analysed retrospectively. We included all adult aSAH patients admitted to our academic hospital between January 2016 and January 2018, treated with an external CSF drain. Demographic data, type of external drain used, the severity of the aSAH and complications, up to 30 days after drain placement, were registered. Complications were divided into (1) complications with a direct relation to the external CSF drain and (2) complications that could not be directly related to the use of an external CSF drain referred to as medical complications RESULTS: One hundred and forty drains were implanted in 100 aSAH patients. In total, 112 complications occurred in 59 patients. Thirty-six complications were drain related and 76 were medical complications. The most common complication was infection (n = 34). Drain dislodgement occurred 16 times, followed by meningitis (n = 11) and occlusion (n = 9). A Poisson model showed that the mean number of complications raised by 2.9% for each additional day of drainage (95% CI: 0.6-5.3% p = 0.01). CONCLUSION: Complications are common in patients with aneurysmal subarachnoid haemorrhage of which 32% are drain-related. A correlation is present between drainage period and the number of complications. Therefore, reducing drainage period could be a target for further improvement of care.


Assuntos
Vazamento de Líquido Cefalorraquidiano/epidemiologia , Derivações do Líquido Cefalorraquidiano/efeitos adversos , Drenagem/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Hemorragia Subaracnóidea/cirurgia , Adulto , Idoso , Vazamento de Líquido Cefalorraquidiano/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia
7.
Cochrane Database Syst Rev ; 11: CD009280, 2020 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-33236783

RESUMO

BACKGROUND: Stroke is the second leading cause of death and a major cause of morbidity worldwide. Retrospective clinical and animal studies have demonstrated neuroprotective effects of iron chelators in people with haemorrhagic or ischaemic stroke. This is the first update of the original Cochrane Review published in 2012. OBJECTIVES: To evaluate the effectiveness and safety of iron-chelating drugs in people with acute stroke. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register (2 September 2019), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2019, Issue 9; 2 September 2019), MEDLINE Ovid (2 September 2019), Embase Ovid (2 September 2019), and Science Citation Index (2 September 2019). We also searched ongoing trials registers. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of iron chelators versus no iron chelators or placebo for the treatment of acute stroke, including subarachnoid haemorrhage. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the search results. We obtained the full texts of potentially relevant studies and evaluated them for eligibility. We assessed risk of bias using the Cochrane 'Risk of bias' tool, and the certainty of evidence using the GRADE approach. MAIN RESULTS: Two RCTs (333 participants) were eligible for inclusion; both compared the iron-chelating agent deferoxamine against placebo. Both studies evaluated participants with spontaneous intracerebral haemorrhage. We assessed one study to have a low risk of bias; the other study had potential sources of bias. The limited and heterogeneous data did not allow for meta-analysis of the outcome parameters. The evidence suggests that administration of deferoxamine may result in little to no difference in deaths (8% in placebo vs 8% in deferoxamine at 180 days; 1 RCT, 291 participants; low-certainty evidence). These RCTs suggest that there may be little to no difference in good functional outcome (modified Rankin Scale score 0 to 2) between groups at 30, 90 and 180 days (placebo vs deferoxamine: 67% vs 57% at 30 days and 36% vs 45% at 180 days; 2 RCTs, 333 participants; low-certainty evidence). One RCT suggests that administration of deferoxamine may not increase the number of serious adverse events or deaths (placebo vs deferoxamine: 33% vs 27% at 180 days; risk ratio 0.81, 95 % confidence interval 0.57 to 1.16; 1 RCT, 291 participants; low-certainty evidence). No data were available on any deaths within the treatment period. Deferoxamine may result in little to no difference in the evolution of National Institute of Health Stroke Scale scores from baseline to 90 days (placebo vs deferoxamine: 13 to 4 vs 13 to 3; P = 0.37; 2 RCTs, 333 participants; low-certainty evidence). Deferoxamine may slightly reduce relative oedema surrounding intracerebral haemorrhage at 15 days (placebo vs deferoxamine: 1.91 vs 10.26; P = 0.042; 2 RCTs, 333 participants; low-certainty evidence). Neither study reported quality of life. AUTHORS' CONCLUSIONS: We identified two eligible RCTs for assessment. We could not demonstrate any benefit for the use of iron chelators in spontaneous intracerebral haemorrhage. The added value of iron-chelating therapy in people with ischaemic stroke or subarachnoid haemorrhage remains unknown.


Assuntos
Desferroxamina/uso terapêutico , Acidente Vascular Cerebral Hemorrágico/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Doença Aguda , Viés , Desferroxamina/efeitos adversos , Acidente Vascular Cerebral Hemorrágico/mortalidade , Humanos , Quelantes de Ferro/efeitos adversos , Fármacos Neuroprotetores/efeitos adversos , Placebos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Eur Radiol ; 29(5): 2724-2726, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30413952

RESUMO

KEY POINTS: Use of algorithms to generate synthetic cases might result in a misrepresentation of the entire population. Training an artificial neural network with a mix of real and synthetic data might lead to non-realistic prediction precision.


Assuntos
Algoritmos , Aneurisma Roto/diagnóstico , Aneurisma Intracraniano/diagnóstico , Redes Neurais de Computação , Feminino , Humanos , Masculino
9.
Br J Neurosurg ; 33(3): 258-260, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28494622

RESUMO

We demonstrate the presence of S100A8 and S100A9 proteins in the wall and thrombosed lumen of an enlarged intracranial aneurysm after flow diverter treatment. These proteins have shown to play an important role in vascular inflammation and may serve as a biomarker and potential therapeutic target for intracranial aneurysms.


Assuntos
Calgranulina A/metabolismo , Calgranulina B/metabolismo , Aneurisma Intracraniano/metabolismo , Aneurisma Intracraniano/cirurgia , Angiografia Digital , Prótese Vascular , Implante de Prótese Vascular , Calgranulina A/análise , Calgranulina B/análise , Embolização Terapêutica , Procedimentos Endovasculares , Feminino , Humanos , Imuno-Histoquímica , Aneurisma Intracraniano/diagnóstico por imagem , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Resultado do Tratamento , Transtornos da Visão/etiologia
10.
Acta Orthop ; 85(6): 600-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25238431

RESUMO

BACKGROUND AND PURPOSE: The bone impaction grafting technique restores bone defects in total hip replacement. Porous titanium particles (TiPs) are deformable, like bone particles, and offer better primary stability. We addressed the following questions in this animal study: are impacted TiPs osteoconductive under loaded conditions; do released micro-particles accelerate wear; and are systemic titanium blood levels elevated after implantation of TiPs? ANIMALS AND METHODS: An AAOS type-III defect was created in the right acetabulum of 10 goats weighing 63 (SD 6) kg, and reconstructed with calcium phosphate-coated TiPs and a cemented polyethylene cup. A stem with a cobalt chrome head was cemented in the femur. The goats were killed after 15 weeks. Blood samples were taken pre- and postoperatively. RESULTS: The TiP-graft layer measured 5.6 (SD 0.8) mm with a mean bone ingrowth distance of 2.8 (SD 0.8) mm. Cement penetrated 0.9 (0.3-1.9) mm into the TiPs. 1 reconstruction showed minimal cement penetration (0.3 mm) and failed at the cement-TiP interface. There were no signs of accelerated wear, metallic particle debris, or osteolysis. Median systemic titanium concentrations increased on a log-linear scale from 0.5 (0.3-1.1) parts per billion (ppb) to 0.9 (0.5-2.8) ppb (p=0.01). INTERPRETATION: Adequate cement pressurization is advocated for impaction grafting with TiPs. After implantation, calcium phosphate-coated TiPs were osteoconductive under loaded conditions and caused an increase in systemic titanium concentrations. However, absolute levels remained low. There were no signs of accelerated wear. A clinical pilot study should be performed to prove that application in humans is safe in the long term.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/efeitos adversos , Prótese de Quadril/efeitos adversos , Osteólise/etiologia , Falha de Prótese/efeitos adversos , Titânio/efeitos adversos , Animais , Transplante Ósseo/efeitos adversos , Transplante Ósseo/métodos , Fosfatos de Cálcio/farmacologia , Cimentação/métodos , Materiais Revestidos Biocompatíveis/farmacologia , Modelos Animais de Doenças , Cabras , Teste de Materiais , Polietileno/farmacologia , Porosidade , Procedimentos de Cirurgia Plástica/efeitos adversos , Titânio/sangue
11.
Front Bioeng Biotechnol ; 11: 1204643, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600319

RESUMO

Objectives: The goal of this project is to explore the views, expectations and preferences of patients with an unruptured intracranial aneurysm regarding the use of AR in patient education. Methods: To gain an in-depth understanding of the patients' perspective, a face-to-face interview study was conducted using an interview protocol with a predefined topic list. All interviews were audio-recorded and transcribed verbatim afterwards. Transcripts were analyzed using thematic content analyses. Coding was performed using Atlas.ti software. Results: Seventeen interviews were conducted. The views, expectations and preferences of patients regarding patient education with AR could be subdivided into 15 categories, which could be grouped into 4 general themes: 1) experiences with current patient education, 2) expectations of AR in patient education, 3) opportunities and limitations of AR, and 4) out-of-hospital use of an AR application. Patients' expectations were predominantly positive regarding improving patients' understanding of their medical situation and doctor-patient communication. Discusssion: This study suggests that patients with unruptured intracranial aneurysms are open to receive patient education regarding their disease with AR. Patients expect that AR models can help patients with intra-cranial aneurysms better understand their disease, treatment options and risks. Additionally, patients expect AR could improve doctor-patient communication.

12.
J Neurointerv Surg ; 15(2): 163-171, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35393338

RESUMO

BACKGROUND: The eCLIPs bifurcation remodelling system is a non-circumferential implant that bridges the neck from outside of a bifurcation aneurysm. The goal of the multicenter, post-marketing European eCLIPs Safety, FeasIbility, and Efficacy Study (EESIS), was to present the efficacy and safety results of the eCLIPs device after 365 days of follow-up. METHODS: All patients were to receive an eCLIPs in conjunction with coils. The study was conducted according to good clinical practices and included independent adjudication of safety and efficacy outcomes. RESULTS: Twenty patients were enrolled at four European centers. Mean age was 60 years (range 41-74) and aneurysms were located at the basilar tip (n=19) and carotid tip (n=1). Average aneurysm dome height was 6.0 mm (range 2.0-15.0). Mean neck length was 5.1 mm (range 2.6-8.5). The technical success rate was 90% (18 of 20). No major territorial strokes or deaths occurred between the index procedure and after 365 days of follow-up. Complete occlusion was achieved in 60% of patients (12 of 20 patients) and 67% of patients with an eCLIPs device (12 of 18) after 365 days of follow-up. Adequate occlusion (complete occlusion and neck remnant) was achieved in 80% of patients (16 of 20 patients) and 89% of patients with an eCLIPs device (16 of 18 patients) after 365 days of follow-up. CONCLUSION: In this small series, treatment with eCLIPs was feasible, safe, and efficacious, considering the challenging nature of the aneurysms. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov NCT02607501.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Estudos de Viabilidade , Próteses e Implantes , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos
13.
PLoS One ; 18(12): e0293353, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38134125

RESUMO

BACKGROUND: Reliably capturing sub-millimeter vessel wall motion over time, using dynamic Computed Tomography Angiography (4D CTA), might provide insight in biomechanical properties of these vessels. This may improve diagnosis, prognosis, and treatment decision making in vascular pathologies. PURPOSE: The aim of this study is to determine the most suitable image reconstruction method for 4D CTA to accurately assess harmonic diameter changes of vessels. METHODS: An elastic tube (inner diameter 6 mm, wall thickness 2 mm) was exposed to sinusoidal pressure waves with a frequency of 70 beats-per-minute. Five flow amplitudes were set, resulting in increasing sinusoidal diameter changes of the elastic tube, measured during three simulated pulsation cycles, using ECG-gated 4D CTA on a 320-detector row CT system. Tomographic images were reconstructed using one of the following three reconstruction methods: hybrid iterative (Hybrid-IR), model-based iterative (MBIR) and deep-learning based (DLR) reconstruction. The three reconstruction methods where based on 180 degrees (half reconstruction mode) and 360 degrees (full reconstruction mode) raw data. The diameter change, captured by 4D CTA, was computed based on image registration. As a reference metric for diameter change measurement, a 9 MHz linear ultrasound transducer was used. The sum of relative absolute differences (SRAD) between the ultrasound and 4D CTA measurements was calculated for each reconstruction method. The standard deviation was computed across the three pulsation cycles. RESULTS: MBIR and DLR resulted in a decreased SRAD and standard deviation compared to Hybrid-IR. Full reconstruction mode resulted in a decreased SRAD and standard deviations, compared to half reconstruction mode. CONCLUSIONS: 4D CTA can capture a diameter change pattern comparable to the pattern captured by US. DLR and MBIR algorithms show more accurate results than Hybrid-IR. Reconstruction with DLR is >3 times faster, compared to reconstruction with MBIR. Full reconstruction mode is more accurate than half reconstruction mode.


Assuntos
Angiografia por Tomografia Computadorizada , Interpretação de Imagem Radiográfica Assistida por Computador , Angiografia por Tomografia Computadorizada/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Angiografia/métodos , Algoritmos , Processamento de Imagem Assistida por Computador , Doses de Radiação
14.
Brain Sci ; 12(5)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35624990

RESUMO

Intracranial aneurysms are pouch-like extrusions from the vessels at the base of the brain which can rupture and cause a subarachnoid hemorrhage. The pathophysiological mechanism of aneurysm formation is thought to be a consequence of blood flow (hemodynamic) induced changes on the endothelium. In this study, the results of a personalized aneurysm-on-a-chip model using patient-specific flow parameters and patient-specific cells are presented. CT imaging was used to calculate CFD parameters using an immersed boundary method. A microfluidic device either cultured with human umbilical vein endothelial cells (HUVECs) or human induced pluripotent stem cell-derived endothelial cells (hiPSC-EC) was used. Both types of endothelial cells were exposed for 24 h to either 0.03 Pa or 1.5 Pa shear stress, corresponding to regions of low shear and high shear in the computational aneurysm model, respectively. As a control, both cell types were also cultured under static conditions for 24 h as a control. Both HUVEC and hiPSC-EC cultures presented as confluent monolayers with no particular cell alignment in static or low shear conditions. Under high shear conditions HUVEC elongated and aligned in the direction of the flow. HiPSC-EC exhibited reduced cell numbers, monolayer gap formation and cells with aberrant, spread-out morphology. Future research should focus on hiPSC-EC stabilization to allow personalized intracranial aneurysm models.

15.
Brain Sci ; 12(3)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35326350

RESUMO

BACKGROUND: patients with a subarachnoid hemorrhage (SAH) might need a flow diverter (FD) placement for complex acutely ruptured intracranial aneurysms (IAs). We conducted a meta-analysis and developed a prediction model to estimate the favorable clinical outcome after the FD treatment in acutely ruptured IAs. METHODS: a systematic literature search was performed from 2010 to January 2021 in PubMed and Embase databases. Studies with more than five patients treated with FDs within fifteen days were included. In total, 1157 studies were identified. The primary outcome measure was the favorable clinical outcome (mRS 0-2). Secondary outcome measures were complete occlusion rates, aneurysm rebleeding, permanent neurologic deficit caused by procedure-related complications, and all-cause mortality. A prediction model was constructed using individual patient-level data. RESULTS: 26 retrospective studies with 357 patients and 368 aneurysms were included. The pooled rates of the favorable clinical outcome, mortality, and complete aneurysm occlusion were 73.7% (95% CI 64.7-81.0), 17.1% (95% CI 13.3-21.8), and 85.6% (95% CI 80.4-89.6), respectively. Rebleeding occurred in 3% of aneurysms (11/368). The c-statistic of the final model was 0.83 (95% CI 0.76-0.89). All the studies provided a very low quality of evidence. CONCLUSIONS: FD treatment can be considered for complex ruptured IAs. Despite high complication rates, the pooled clinical outcomes seem favorable. The prediction model needs to be validated by larger prospective studies before clinical application.

16.
Tissue Eng Part B Rev ; 28(6): 1169-1179, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34915758

RESUMO

The large number of animal models used in spinal cord injury (SCI) research complicates the objective selection of the most appropriate model to investigate the efficacy of biomaterial-based therapies. This systematic review aims to identify a list of relevant animal models of SCI by evaluating the confirmation of SCI and animal survival in all published SCI models used in biomaterials research up until April 2021. A search in PubMed and Embase based on "spinal cord injury," "animal models," and "biomaterials" yielded 4606 papers, 393 of which were further evaluated. A total of 404 individual animal experiments were identified based on type of SCI, level of SCI, and the sex, species, and strain of the animals used. Finally, a total of 149 unique animal models were comparatively evaluated, which led to the generation of an evidence-based list of well-documented mid-thoracic rat models of SCI. These models were used most often, clearly confirmed SCI, and had relatively high survival rates, and therefore could serve as a future starting point for studying novel biomaterial-based therapies for SCI. Furthermore, the review discusses (1) the possible risk of bias in SCI animal models, (2) the difficulty in replication of such experiments due to frequent poor reporting of the methods and results, and (3) the clinical relevance of the currently utilized models. Systematic review registration: The study was prospectively registered in PROSPERO, registration number CRD42019141162. Impact statement Studies on biomaterial-based therapies within the field of spinal cord injury (SCI) research show a large inconsistency concerning the selection of animal models. This review goes beyond summarizing the existing gaps between experimental and clinical SCI by systematically evaluating all animal models used within this field. The models identified by this work were used most often, clearly confirmed SCI, and had a relatively high survival rate. This evidence-based list of well-documented animal models will serve as a practical guideline in future research on innovative biomaterial-based therapies for SCI.


Assuntos
Materiais Biocompatíveis , Traumatismos da Medula Espinal , Animais , Ratos , Materiais Biocompatíveis/uso terapêutico , Traumatismos da Medula Espinal/terapia , Modelos Animais de Doenças
17.
Pain Med ; 12(6): 988; author reply 989, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21676157

RESUMO

Article: Bogduk Nikolai, MacVicar J, Borowczyk J. The pain of vertebral compression fractures can arise in the posterior elements. Pain Med 2010;11:1666-73.


Assuntos
Fraturas por Compressão/fisiopatologia , Dor/fisiopatologia , Fraturas da Coluna Vertebral/fisiopatologia , Coluna Vertebral/fisiopatologia , Feminino , Humanos , Masculino
18.
Arch Orthop Trauma Surg ; 131(5): 711-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21161665

RESUMO

BACKGROUND: Electron beam melting (E-beam) is a new technology to produce 3-dimensional surface topographies for cementless orthopedic implants. METHODS: The friction coefficients of two newly developed E-beam produced surface topographies were in vitro compared with sandblasted E-beam and titanium plasma sprayed controls. Bone ingrowth (direct bone-implant contact) was determined by implanting the samples in the femoral condyles of 6 goats for a period of 6 weeks. RESULTS: Friction coefficients of the new structures were comparable to the titanium plasma sprayed control. The direct bone-implant contact was 23.9 and 24.5% for the new surface structures. Bone-implant contact of the sandblasted and titanium plasma sprayed control was 18.2 and 25.5%, respectively. CONCLUSIONS: The frictional and bone ingrowth properties of the E-beam produced surface structures are similar to the plasma-sprayed control. However, since the maximal bone ingrowth had not been reached for the E-beam structures during the relatively short-term period, longer-term follow-up studies are needed to assess whether the E-beam structures lead to a better long-term performance than surfaces currently in use, such as titanium plasma spray coating.


Assuntos
Ligas/química , Substitutos Ósseos/química , Próteses e Implantes , Titânio/química , Animais , Elétrons , Feminino , Cabras , Imageamento Tridimensional , Teste de Materiais/métodos , Porosidade , Propriedades de Superfície
19.
Brain Sci ; 11(6)2021 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067446

RESUMO

BACKGROUND: Automated cerebrospinal fluid (CSF) drainage systems allow for the mobilization of patients with an external CSF drain. The aim of this study is to describe the implementation of an automated CSF drainage system in neurosurgical patients with external CSF drains. METHODS: A feasibility study was performed using an automated CSF drainage system (LiquoGuard®7, Möller Medical GmbH, Fulda, Germany) in adult neurosurgical patients treated with external lumbar or external ventricular drains between December 2017 and June 2020. Limited mobilization was allowed-patients were allowed to adjust their inclined beds, sit in chairs and walk under the supervision of a nurse or physical therapist. The primary outcome was the number of prematurely terminated drainage sessions. RESULTS: Twenty-three patients were included. Drainage was terminated prematurely in eight (35%) patients. In three (13%) of these patients, drainage was terminated due to signs of hydrocephalus. Pressure-controlled drainage in patients with external lumbar drains (ELD) showed inaccurate pressure curves, which was solved by using volume-controlled drainage in ELD patients. CONCLUSION: The implementation of an automated CSF drainage system (LiquoGuard®7) for CSF drainage allows for early mobilization in a subset of patients with external CSF drains. External lumbar drains require volume-based drainage rather than differential pressure-dependent drainage.

20.
World Neurosurg ; 154: e185-e198, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246826

RESUMO

BACKGROUND: Detection of multiple intracranial aneurysms (MIAs) in patients with aneurysmal subarachnoid hemorrhage (aSAH) is common and the optimal management of the additional unruptured intracranial aneurysms (UIA) is often a matter of debate. We calculate the incidence and the factors associated with subsequent aSAHs from untreated additional aneurysms in a single-center group of patients with aSAH and MIAs. METHODS: Charts of patients with MIAs admitted to our neurosurgery department for aSAH between January 2000 and March 2020 were retrospectively reviewed. Incidence rate and factors associated with subsequent aSAHs were calculated with univariable and multivariable analyses. RESULTS: Of the unruptured aneurysms, 50% were preventively treated. During a median follow-up of 3 years, 20 of 174 patients (11.5%) presented with a second aSAH. Incidence of rupture of an additional untreated aneurysm was 18.05 per 1000 person/years (confidence interval, 10.69-30.47). Rupture incidence of an additional aneurysm located in the anterior circulation was 32.70 per 1000 person/years and 40.73 per 1000 person/years in the posterior circulation. Presence of untreated mirror and de novo aneurysms increased the risk of overall subsequent aSAHs by 16.9-fold and 7.6-fold, respectively. Most untreated additional aneurysms causing a subsequent aSAH were smaller than 7 mm (73.3%), with middle cerebral artery being the most frequent location (40.0%). CONCLUSIONS: Incidence of subsequent aSAHs is high in patients with aSAH-MIA. Untreated mirror and de novo aneurysms are associated with higher rupture risk. Longer follow-up and prophylactic treatment of asymptomatic aneurysms at higher rupture risk are recommended to prevent the significant poor outcome of subsequent aSAHs.


Assuntos
Aneurisma Intracraniano/patologia , Hemorragia Subaracnóidea/patologia , Adulto , Idoso , Aneurisma Roto/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/epidemiologia , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/patologia , Procedimentos Neurocirúrgicos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/etiologia , Resultado do Tratamento
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