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1.
Eur Rev Med Pharmacol Sci ; 27(4): 1625-1632, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36876707

RESUMO

OBJECTIVE: This study examines the role of MTHFR gene polymorphism (rs1801133) in women with lipedema (LIPPY) body composition parameters compared to a control group (CTRL). SUBJECTS AND METHODS: We carried out a study on a sample of 45 LIPPY and 50 women as a CTRL. Body composition parameters were examined by Dual-energy X-ray Absorptiometry (DXA). A genetic test was performed for the MTHFR polymorphism (rs1801133, 677C>T) using a saliva sample for LIPPY and CTRL groups. Mann-Whitney tests evaluated statistically significant differences between four groups (carriers and non-carriers of the MTHFR polymorphism for LIPPY and CTRL groups) on anthropometric/body composition parameters to identify patterns. RESULTS: LIPPY showed significantly higher (p<0.05) anthropometric parameters (weight, BMI, waist, abdominal, hip circumferences) and lower waist/hip ratio (p<0.05) compared to the CTRL group. The association between the polymorphism alleles related to the rs1801133 MTHFR gene and the body composition values LIPPY carriers (+) showed an increase in fat tissue of legs and fat region of legs percentage, arm's fat mass (g), leg's fat mass (g), and leg's lean mass (g) (p<0.05) compared to CTRL (+). Lean/fat arms and lean/fat legs were lower (p<0.05) in LIPPY (+) than in CTRL (+). In the LIPPY (+), the risk of developing the lipedema disease was 2.85 times higher (OR=2.85; p<0.05; 95% confidence interval = 0.842-8.625) with respect to LIPPY (-) and CTRL. CONCLUSIONS: The presence or absence of MTHFR polymorphism offers predictive parameters that could better characterize women with lipedema based on the association between body composition and MTHFR presence.


Assuntos
Lipedema , Metilenotetra-Hidrofolato Redutase (NADPH2) , Feminino , Humanos , Absorciometria de Fóton , Tecido Adiposo , Alelos , Composição Corporal , Lipedema/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética
2.
J Plast Reconstr Aesthet Surg ; 77: 298-308, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36610275

RESUMO

BACKGROUND: The knee region represents a challenging area of soft tissue reconstruction. Specifically, in the context of total knee arthroplasty (TKA) or following high-energy trauma with fractures and hardware fixation, soft tissue defects can expose critical structures such as joint, bone or tendon, besides the implant/plates themselves, with dramatic consequences in terms of postoperative infection and hardware contamination. METHODS: A retrospective study was conducted on a prospectively maintained database from January 2016 to February 2021. Inclusion criteria involved all patients who underwent an implant-associated infection of the knee and upper third of the leg coupled with a soft tissue reconstruction (STR) using the traditional gastrocnemius muscle (GM) pedicled flap or the chimeric GM-MSAP (medial sural artery perforator) flap. RESULTS: Thirty-eight patients were included (group A, GM flap, 22 patients; group B, chimeric GM-MSAP flap, 16 patients). No statistically significant differences were detected in terms of age, comorbidities, defect size, follow-up, and flap complications. A statistically significant difference was seen among the groups in terms of successful flap re-raise (required because of a persistent infection of the implant or in a two-stage procedure setting, including the use of a cemented spacer) in favour of the GM-MSAP group. CONCLUSION: The chimeric GM-MSAP, being safer to reraise if required, can be a significantly more powerful tool in those cases in which a two-stage procedure is planned or when there is a high probability for secondary intervention need, reducing the need to convert to either free flap coverage or amputation.


Assuntos
Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Retalhos Cirúrgicos/irrigação sanguínea , Músculo Esquelético/transplante , Complicações Pós-Operatórias/cirurgia , Retalho Perfurante/irrigação sanguínea , Lesões dos Tecidos Moles/cirurgia
3.
Eur Rev Med Pharmacol Sci ; 24(6): 3236-3244, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32271442

RESUMO

OBJECTIVE: Lipedema is a disorder of adipose tissue characterized by abnormal subcutaneous fat deposition, leading to swelling and enlargement of the lower limbs and trunk. The aim of this study was to evaluate the lipedema phenotype by investigating the role of polymorphisms related to IL-6 (rs1800795) gene in people with diagnosis of lipedema. The second aim was to identify indicators of body composition, useful for a differential analysis between subjects with lipedema and the control group. PATIENTS AND METHODS: Two groups are involved in the study, 45 women with lipedema (LIPPY) and 50 women randomly chosen from the population as Control (CTRL). Clinical and demographical variables recorded include weight, height, body mass index (BMI) and circumference measurements. Body composition (Fat mass, FM; lean mass, LM) was assessed by Dual-energy X-ray Absorptiometry (DXA). The genetic tests for IL-6 (rs18oo795) gene were performed for both groups, using a saliva sample. RESULTS: The study of the relationship between the IL-6 (rs1800795) gene polymorphism, the anthropometric values and the body composition indices has provided the following significant results: subjects with diagnosis of lipedema present statistically significant increased values with regard to weight, BMI, waist, abdomen and hip circumferences, arms, legs and whole FM (% and kg), gynoid FM (kg), legs LM (kg) and ASMMI. Moreover, the value of the waist hip ratio was found to be decreased. CONCLUSIONS: For the first time, we suggested that IL-6 gene polymorphism could characterize subjects with lipedema respect to Normal Weight Obese and obese subjects. The intra-group comparisons (LIPPY carriers vs. LIPPY non-carriers and CTRL carriers vs. CTRL non-carriers) showed no statistically significant values. In contrast, the inter-group comparisons (LIPPY non-carriers vs. CTRL non-carriers and LIPPY carriers vs. CTRL carriers) resulted statistically significant. We have identified other indices, such as leg index, trunk index, abdominal index, total index, that could be promising clinical tools for diagnosis of the lipedema phenotype and for predicting the evolution of the disease.


Assuntos
Interleucina-6/genética , Lipedema/genética , Polimorfismo Genético/genética , Adulto , Feminino , Humanos , Lipedema/diagnóstico , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
5.
Indian J Plast Surg ; 53(3): 423-426, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33402777

RESUMO

The development of a tracheocutaneous fistula (TCF) is a well-documented complication after tracheostomy, especially in chronic morbid patients, in whom tubes or cannulas are left in place over time, or in irradiated patients. Surgical treatments are therefore needed which range from simple curettage and dressings to local skin flaps, muscle flaps and, in the more complex cases, microsurgical free tissue transfers. We present a novel combined technique used to successfully treat recurrent TCFs in irradiated patients, involving a superiorly based turnover fistula flap and a sternocleidomastoid transposition flap.

7.
J Med Vasc ; 42(1): 39-45, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28705446

RESUMO

OBJECTIVES: A novel stent method to simplify treatment of proximal ascending aorta and aortic arch aneurysms was developed and investigated by finite element analysis. Therapy of ascending aortic and aortic arch aneurysms is difficult and challenging and is associated with various complications. METHODS: A 55mm wide×120mm long stent was designed without the stent graft and the stent was deployed by an endovascular method in a virtual patient-specific aneurysm model. The stress-strain analysis and deployment characteristics were performed in a finite element analysis using the Abaqus software. RESULTS: The stent, when embedded in the aortic wall, significantly reduced aortic wall stresses, while preserving the side coronary ostia and side branches in the aortic arch. When tissue growth was modeled computationally over the stent struts the wall stresses in aorta was reduced. This effect became more pronounced when increasing the thickness of the tissue growth. There were no abnormal stresses in the aorta, coronary ostium and at the origin of aortic branches. The stent reduced aneurysm expansion cause by hypertensive condition from 2mm without stenting to 1.3mm after stenting and embedding. CONCLUSION: In summary, we uncovered a simple treatment method using a bare nitinol stent without stent graft in the treatment of the proximal aorta and aortic arch aneurysms, which could eventually replace the complex treatment methods for this disease.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Stents , Simulação por Computador , Procedimentos Endovasculares , Análise de Elementos Finitos , Humanos , Modelos Anatômicos , Desenho de Prótese
8.
Bone Marrow Transplant ; 52(6): 859-862, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28287644

RESUMO

Acute GvHD (aGvHD) is a life-threatening complication of hematopoietic stem cell transplantation. Frontline therapy for aGvHD consists of corticosteroid administration. However, ∼25% of the patients have a steroid-refractory disease, a sign of poor prognosis. An alternative therapy for steroid-refractory aGvHD is infusion of mesenchymal stromal cells (MSCs). Herein, we report the results of 46 patients treated with MSC infusion as salvage therapy for steroid-refractory aGvHD III/IV (78% grade IV). Patients received a median cumulative dose of MSCs of 6.81 × 106/kg (range, 0.98-29.78 × 106/kg) in a median of 3 infusions (range, 1-7). Median time between the onset of aGvHD and the first MSC infusion was 25.5 days (range, 6-153). Of the patients, 50% (23/46) presented clinical improvement. Of these, 3 patients (13%) had complete response, 14 (61%) had partial response and 6 (26%) had transient partial response. The estimated probability of survival at 2s year was 17.4%. Only 2 patients (4.3%) presented acute transient side effects (nausea/vomiting and blurred vision) during cell infusion. No patient had late or severe side effects because of MSC infusion. These results suggest that this therapeutic modality is safe and should be considered for steroid-refractory aGvHD, especially in countries where other second-line agents are less available.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Mesenquimais , Doença Aguda , Adolescente , Adulto , Idoso , Aloenxertos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/terapia , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Esteroides/administração & dosagem , Taxa de Sobrevida
9.
Transfus Med ; 26(4): 297-300, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27237104

RESUMO

OBJECTIVES: Evaluate whether poor mobilisers had delayed haematopoietic (neutrophil and platelet) recovery despite receiving similar cell dose as good mobilisers. BACKGROUND: Autologous haematopoietic progenitor cell (HPC) transplantation is indicated to treat some haematological malignancies. This procedure requires HPC mobilisation from bone marrow to peripheral blood. Cell dose is important for a fast haematological recovery. Despite being poor mobilisers, some patients can collect enough cell numbers for transplantation. RESULTS: Fifteen poor mobiliser patients (peak of CD34+ cells ≤10 µL(-1) in peripheral blood) were transplanted at our institution. Haematological recovery (neutrophil ≥ 500 µL(-1) ) in this group was compared to that observed in the group of 16 patients of good mobilisers (peak of CD34+ cells ≥20 µL(-1) in peripheral blood) who received similar cell dose (2·637 ± 0·1744 × 10(6) kg(-1) vs 2·727 ± 0·1746 × 10(6) kg(-1) ; P = 0·7177). The poor mobiliser group had neutrophil and platelet recovery later than the good mobiliser group (on day 12, range 9-14 vs day 10, range 9-22, P = 0·0381 for neutrophil, and on day 22·89 ± 11·16 and 14·08 ± 4·821, P = 0·0193 for platelet). Mortality rates and transfusion requirements were not different between the groups. CONCLUSION: Poor mobilisers have delayed neutrophil and platelet recovery after autologous HPC transplantation despite having received the same cell dose as good mobilisers.


Assuntos
Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas , Adulto , Idoso , Autoenxertos , Intervalo Livre de Doença , Feminino , Neoplasias Hematológicas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
10.
Artigo em Inglês | MEDLINE | ID: mdl-26208183

RESUMO

The trend towards realistic numerical models of (pathologic) patient-specific vascular structures brings along larger computational domains and more complex geometries, increasing both the computation time and the operator time. Hexahedral grids effectively lower the computational run time and the required computational infrastructure, but at high cost in terms of operator time and minimal cell quality, especially when the computational analyses are targeting complex geometries such as aneurysm necks, severe stenoses and bifurcations. Moreover, such grids generally do not allow local refinements. As an attempt to overcome these limitations, a novel approach to hexahedral meshing is proposed in this paper, which combines the automated generation of multi-block structures with a grid-based method. The robustness of the novel approach is tested on common complex geometries, such as tree-like structures (including trifurcations), stenoses, and aneurysms. Additionally, the performance of the generated grid is assessed using two numerical examples. In the first example, a grid sensitivity analysis is performed for blood flow simulated in an abdominal mouse aorta and compared to tetrahedral grids with a prismatic boundary layer. In the second example, the fluid-structure interaction in a model of an aorta with aortic coarctation is simulated and the effect of local grid refinement is analyzed.


Assuntos
Aorta Abdominal/ultraestrutura , Modelos Cardiovasculares , Animais , Aorta Abdominal/metabolismo , Hemodinâmica , Camundongos
11.
Transplant Proc ; 47(8): 2548-51, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26518969

RESUMO

BACKGROUND: There is no standard treatment for patients with severe anemia who refuse blood transfusion or cannot receive red blood cells. CASE REPORT: After an orthotopic liver transplantation, an elderly Jehovah's Witness who refused blood transfusion presented with severe acute anemia with hemorrhagic shock. The calculated red blood cell loss was near 70%. Associated with surgical treatment and supportive measures, the patient was treated with high-dose erythropoietin and ferric carboxymaltose. RESULTS: The patient presented a rapid increase in hemoglobin concentration and reticulocyte count with resolution of hemorrhagic shock after the proposed pharmacologic treatment combined with local hemostatic measures. She was transferred to a low-risk unit 4 days after transplantation and was discharged from the hospital on day 10. The hemoglobin concentration was normal 35 days after the bleeding event. CONCLUSION: This case demonstrated that a protocol with high-dose erythropoietin and ferric carboxymaltose may be an option for patients with severe anemia who refuse blood transfusion or cannot receive red blood cells.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/administração & dosagem , Compostos Férricos/uso terapêutico , Testemunhas de Jeová , Transplante de Fígado/efeitos adversos , Maltose/análogos & derivados , Anemia/etiologia , Transfusão de Sangue/estatística & dados numéricos , Feminino , Humanos , Maltose/uso terapêutico , Pessoa de Meia-Idade , Contagem de Reticulócitos , Choque Hemorrágico/tratamento farmacológico , Choque Hemorrágico/etiologia , Resultado do Tratamento , Recusa do Paciente ao Tratamento
12.
Ann Hematol ; 94(8): 1319-26, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25869029

RESUMO

In the present analysis, we evaluated whether in elderly acute myeloid leukemia (AML) patients (>60 years), minimal residual disease (MRD) assessed by flow cytometry may have a role in guiding choice of postremission strategies. We analyzed 149 young and 61 elderly adults who achieved morphological CR after induction course of EORTC/GIMEMA protocols. Elderly patients reached a postconsolidation MRD negative status less frequently than younger ones (11 vs 28 %, p = 0.009). MRD negativity resulted in a longer 5-year disease-free survival (DFS) both in elderly (57 vs 13 %, p = 0.0197) and in younger patients (56 vs 31 %, p = 0.0017). Accordingly, 5-year cumulative incidence of relapse (CIR) of both elderly (83 vs 42 %, p = 0.045) and younger patients (59 vs 24 % p = NS) who were MRD positive doubled that of MRD negative ones. Nevertheless, CIR of MRD negative elderly patients was twofold higher than that of younger MRD negative ones (42 vs 24 %, p = NS). In conclusion, elderly patients in whom chemotherapy yields a MRD negative CR have duration of DFS and rate of CIR significantly better than those who remain MRD positive. Nonetheless, the high CIR rate observed in the elderly suggests that MRD negativity might have different therapeutic implications in this population than in the younger counterpart.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Fatores Etários , Idoso , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Indução de Remissão , Prevenção Secundária/métodos , Adulto Jovem
13.
Ann Oncol ; 25(1): 57-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24276029

RESUMO

BACKGROUND: Risk-reducing mastectomy (RRM) decreases breast cancer (BC) risk in BRCA1/2 mutation carriers by up to 95%, but the Italian attitude towards this procedure is reluctant. PATIENTS AND METHODS: This is an observational study with retrospective design, using quantitative and qualitative research methods, aimed at evaluating the attitude towards RRM by rapid genetic counselling and testing (RGCT), at the time of BC diagnosis, compared with traditional genetic counselling and testing (TGCT), after previous BC surgery. Secondary aims were to investigate patient satisfaction after RRM and the rate of occult tumour in healthy breasts. A total of 1168 patients were evaluated: 1058 received TGCT, whereas 110 underwent RGCT. RESULTS: In TGCT, among 1058 patients, 209 (19.7%) mutation carriers were identified, with the rate of RRM being 4.7% (10 of 209). Conversely in RGCT, among 110 patients, 36 resulted positive, of which, 15 (41.7%) underwent bilateral mastectomy at the BC surgery time, showing an overall good satisfaction, measured by interpretative phenomenological analysis 12 months after the intervention. CONCLUSIONS: Our study shows that RGCT in patients with a hereditary profile is associated with a high rate of RRM at the BC surgery time, this being the pathway offered within a multidisciplinary organization.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Aconselhamento Genético , Testes Genéticos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Feminino , Humanos , Itália , Mastectomia , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-22149183

RESUMO

Carotid artery stenting (CAS) has emerged as a minimally invasive alternative to endarterectomy but its use in clinical treatment is limited due to the post-stenting complications. Haemodynamic actors, related to blood flow in the stented vessel, have been suggested to play a role in the endothelium response to stenting, including adverse reactions such as in-stent restenosis and late thrombosis. Accessing the flow-related shear forces acting on the endothelium in vivo requires space and time resolutions which are currently not achievable with non-invasive clinical imaging techniques but can be obtained from image-based computational analysis. In this study, we present a framework for accurate determination of the wall shear stress (WSS) in a mildly stenosed carotid artery after the implantation of a stent, resembling the commercially available Acculink (Abbott Laboratories, Abbott Park, Illinois, USA). Starting from angiographic CT images of the vessel lumen and a micro-CT scan of the stent, a finite element analysis is carried out in order to deploy the stent in the vessel, reproducing CAS in silico. Then, based on the post-stenting anatomy, the vessel is perfused using a set of boundary conditions: total pressure is applied at the inlet, and impedances that are assumed to be insensitive to the presence of the stent are imposed at the outlets. Evaluation of the CAS outcome from a geometrical and haemodynamic perspective shows the presence of atheroprone regions (low time-average WSS, high relative residence time) colocalised with stent malapposition and stent strut interconnections. Stent struts remain unapposed in the ostium of the external carotid artery disturbing the flow and generating abnormal shear forces, which could trigger thromboembolic events.


Assuntos
Artérias Carótidas/cirurgia , Stents , Fenômenos Biomecânicos , Artérias Carótidas/fisiopatologia , Estenose das Carótidas/cirurgia , Simulação por Computador , Análise de Elementos Finitos , Hemodinâmica , Humanos , Stents/efeitos adversos , Estresse Mecânico
15.
J Biomech ; 46(2): 345-53, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23159095

RESUMO

Although arterio-venous grafts (AVGs) are the second best option as long-term vascular access for hemodialysis, they suffer from complications caused by intimal hyperplasia, mainly located in vessel regions of low and oscillating wall shear stress. However, certain flow patterns in the bulk may reduce these unfavorable hemodynamic conditions. We therefore studied, with computational fluid dynamics (CFD), the impact of a helical AVG design on the occurrence of (un)favorable hemodynamic conditions at the venous anastomosis. Six CFD-models of an AVG in closed-loop configuration were constructed: one conventional straight graft, and five helical designed grafts with a pitch of 105 mm down to 35 mm. At the venous anastomosis, disturbed shear was assessed by quantifying the area with unfavorable conditions, and by analyzing averaged values in a case-specific patch. The bulk hemodynamics were assessed by analyzing the kinetic helicity in and the pressure drop over the graft. The most helical design scores best, being instrumental to suppress disturbed shear in the venous segment. There is, however, no trivial relationship between the number of helix turns of the graft and disturbed shear in the venous segment, when a realistic closed-loop AVG model is investigated. Bulk flow investigation showed a marked increase of helicity intensity in, and a moderate pressure drop over the AVG by introducing a lower pitch. At the venous anastomosis, unfavorable hemodynamic conditions can be reduced by introducing a helical design. However, due to the complex flow conditions, the optimal helical design for an AVG cannot be derived without studying case by case.


Assuntos
Prótese Vascular , Modelos Cardiovasculares , Desenho de Prótese/métodos , Fluxo Pulsátil , Estresse Fisiológico , Humanos , Resistência ao Cisalhamento
16.
J Mech Behav Biomed Mater ; 13: 129-39, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22842656

RESUMO

The presented study details the virtual deployment of a bifurcated stent graft (Medtronic Talent) in an Abdominal Aortic Aneurysm model, using the finite element method. The entire deployment procedure is modeled, with the stent graft being crimped and bent according to the vessel geometry, and subsequently released. The finite element results are validated in vitro with placement of the device in a silicone mock aneurysm, using high resolution CT scans to evaluate the result. The presented work confirms the capability of finite element computer simulations to predict the deformed configuration after endovascular aneurysm repair (EVAR). These simulations can be used to quantify mechanical parameters, such as neck dilations, radial forces and stresses in the device, that are difficult or impossible to obtain from medical imaging.


Assuntos
Análise de Elementos Finitos , Stents , Enxerto Vascular/instrumentação , Aneurisma da Aorta Abdominal/cirurgia , Teste de Materiais , Desenho de Prótese , Silicones
17.
J Biomech ; 45(8): 1353-9, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22483228

RESUMO

There is a growing interest in virtual tools to assist clinicians in evaluating different procedures and devices for endovascular treatment. In the present study we use finite element analysis to investigate the influence of stent design and vessel geometry for stent assisted coiling of intracranial aneurysms. Nine virtual stenting procedures were performed: three nitinol stent designs ((i) an open cell stent resembling the Neuroform, (ii) a generic stiff and (iii) a more flexible closed cell design), were deployed in three patient-specific cerebral aneurysmatic vessels. We investigated the percentage of strut area covering the aneurysm neck, the straightening induced on the cerebrovasculature by the stent placement (quantified by the reduction in tortuosity), and stent apposition to the wall (quantified as the percentage of struts within 0.2mm of the vessel). The results suggest that the open cell design better covers the aneurysm neck (11.0±1.1%) compared to both the stiff (7.8±1.6%) and flexible (8.7±1.6%) closed cell stents, and induces less straightening of the vessel (-5.1±1.6% vs. -42.9±9.8% and -26.9±11.9% ). The open cell design has, however, less struts apposing well to the vessel wall (56.0±6.4%) compared to the flexible (73.4±4.6%) and stiff (70.4±5.1%) closed cell design. With the presented study, we hope to contribute to and improve aneurysm treatment, using a novel patient specific environment as a possible pre-operative tool to evaluate mechanical stent behavior in different vascular geometries.


Assuntos
Artérias Cerebrais/fisiopatologia , Artérias Cerebrais/cirurgia , Circulação Cerebrovascular , Aneurisma Intracraniano/fisiopatologia , Aneurisma Intracraniano/cirurgia , Modelos Cardiovasculares , Stents , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Prótese Vascular , Artérias Cerebrais/patologia , Simulação por Computador , Desenho Assistido por Computador , Análise de Falha de Equipamento , Humanos , Aneurisma Intracraniano/patologia , Desenho de Prótese , Resultado do Tratamento
18.
Ann Biomed Eng ; 40(3): 729-41, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22009313

RESUMO

The purpose of this study is to investigate how the imposition of personalized, non-invasively measured blood flow rates as boundary conditions (BCs) influences image-based computational hemodynamic studies in the human aorta. We extracted from 4D phase-contrast MRI acquisitions of a healthy human (1) the geometry of the thoracic aorta with supra-aortic arteries and (2) flow rate waveforms at all boundaries. Flow simulations were carried out, and the implications that the imposition of different BC schemes based on the measured flow rates have on wall shear stress (WSS)-based indicators of abnormal flow were analyzed. Our results show that both the flow rate repartition among the multiple outlets of the aorta and the distribution and magnitude of the WSS-based indicators are strongly influenced by the adopted BC strategy. Keeping as reference hemodynamic model the one where the applied BC scheme allowed to obtain a satisfactory agreement between the computed and the measured flow rate waveforms, differences in WSS-based indicators up to 49% were observed when the other BC strategies were applied. In conclusion, we demonstrate that in subject-specific computational hemodynamics models of the human aorta the imposition of BC settings based on non-invasively measured flow rate waveforms influences indicators of abnormal flow to a large extent. Hence, a BCs set-up assuring realistic, subject-specific instantaneous flow rate distribution must be applied when BCs such as flow rates are prescribed.


Assuntos
Aorta Torácica/fisiologia , Modelos Cardiovasculares , Aorta Torácica/anatomia & histologia , Engenharia Biomédica , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Hemodinâmica , Humanos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Resistência ao Cisalhamento
20.
Tech Coloproctol ; 16(4): 315-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21678070

RESUMO

Stapled hemorrhoidopexy is a widely used surgical technique for treating hemorrhoids, although severe complications have been reported. The authors report a rare case of extensive ascending intramural hematoma of the sigmoid colon complicating stapled hemorrhoidopexy, with perforation and hemoperitoneum. Diagnosis was established at CT scan and treatment consisted of drainage, suturing, and diverting colostomy. This reported case is the ninth described in the literature, but, so far, it is not known what preventive measures to use in order to avoid such a rare complication. Adoption of a correct surgical technique remains the step of utmost importance in order to prevent such a severe postoperative complication.


Assuntos
Hematoma/etiologia , Hemoperitônio/etiologia , Hemorroidectomia/métodos , Perfuração Intestinal/etiologia , Doenças do Colo Sigmoide/etiologia , Grampeamento Cirúrgico , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Tomografia Computadorizada por Raios X
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