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1.
Pediatr Int ; 66(1): e15754, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38924208

RESUMO

BACKGROUND: Recently, reports of endoscopic approaches for neuroblastoma, ganglioneuroblastoma, and ganglioneuroma (peripheral neuroblastic tumor; PNTs) have been increasing. This study aimed to clarify the indications for endoscopic surgery for PNTs. METHODS: Pediatric patients who underwent endoscopic surgery for PNTs at our institution were included in this study. Image-defined risk factors (IDRFs) were analyzed using preoperative computed tomography (CT). RESULTS: Twenty-four patients underwent endoscopic surgery for PNTs. The diagnoses included neuroblastoma (n = 11), ganglioneuroma (n = 10), and ganglioneuroblastoma (n = 3). Regarding the tumor site, there were 18 cases of adrenal tumors, five cases of mediastinal tumors, and one case of retroperitoneal tumors. Image-defined risk factors were positive in eight cases (contacted with a renal vessel, n = 6; compression of principal bronchi, n = 2). Complete resection was accomplished in 21 cases (14 of 16 IDRF-negative cases and seven of eight IDRF-positive cases). All patients survived without recurrence during the follow-up period. CONCLUSIONS: The CT findings of contact with renal vessels and compression of principal bronchi do not seem to be indicators of incomplete resection. An endoscopic approach to PNTs in pediatric patients is feasible with a good prognosis if patients are selected strictly.


Assuntos
Ganglioneuroblastoma , Ganglioneuroma , Neuroblastoma , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Pré-Escolar , Neuroblastoma/cirurgia , Neuroblastoma/diagnóstico , Criança , Lactente , Ganglioneuroma/cirurgia , Ganglioneuroma/diagnóstico , Ganglioneuroblastoma/cirurgia , Ganglioneuroblastoma/diagnóstico , Estudos Retrospectivos , Endoscopia/métodos , Resultado do Tratamento , Adolescente , Seguimentos , Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias do Mediastino/cirurgia , Neoplasias do Mediastino/diagnóstico
2.
Pediatr Int ; 65(1): e15666, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37888751

RESUMO

BACKGROUND: The aim of this study was to clarify the characteristics and outcomes of pediatric patients with solid pseudopapillary neoplasms (SPNs) who underwent pancreatectomy. METHODS: Pediatric patients with SPNs who underwent pancreatectomy at our institution between 1995 and 2020 were included in the study. RESULTS: During the period under review, 12 patients underwent pancreatectomy for SPNs (median age: 10 years; range: 6-15 years). The surgical procedures included pancreatoduodenectomy (n = 2; 16.6%), distal pancreatectomy (n = 3; 25%), and enucleation (n = 7; 58.3%). The most common postoperative complication was postoperative pancreatic fistula (n = 6; 50%). Patients who underwent enucleation tended to have higher postoperative complication rates compared with those who underwent other procedures. All patients were alive without recurrence at the end of the study period. CONCLUSIONS: SPN is associated with a good prognosis, regardless of the surgical procedure. If surgeons select enucleation for pediatric SPNs, they should bear in mind that it is associated with a higher complication rate.


Assuntos
Neoplasias Pancreáticas , Humanos , Criança , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia , Prognóstico , Pâncreas , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Estudos Retrospectivos
3.
Neuroradiology ; 64(1): 151-159, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34351498

RESUMO

PURPOSE: Endovascular treatment of posterior communicating artery aneurysms with fetal-type posterior communicating artery originating from the aneurysm dome is often challenging because, with conventional techniques, dense packing of aneurysms for posterior communicating artery preservation is difficult; moreover, flow-diversion devices are reportedly less effective. Herein, we describe a novel method called the λ stenting technique that involves deploying stents into the internal carotid artery and posterior communicating artery. METHODS: Between January 2018 and September 2020, the λ stenting technique was performed to treat eight consecutive cases of aneurysms. All target aneurysms had a wide neck (dome/neck ratio < 2), a fetal-type posterior communicating artery with hypoplastic P1, and a posterior communicating artery originating from the aneurysm dome. The origin of the posterior communicating artery from the aneurysm, relative to the internal carotid artery, was steep (< 90°: V shape). RESULTS: The maximum aneurysm size was 8.0 ± 1.9 mm (6-12 mm). The average packing density (excluding one regrowth case) was 32.7 ± 4.2% (26.8-39.1%). Initial occlusion was complete occlusion in 6 (75.0%) patients and neck remnants in 2 (25.0%) patients. Follow-up angiography was performed at 18.4 ± 11.6 months (3-38 months). There were no perioperative complications or reinterventions required during the study period. CONCLUSION: The λ stenting technique enabled dense coil packing and preservation of the posterior communicating artery. This technique enabled safe and stable coil embolization. Thus, it could become an alternative treatment option for this sub-type of intracranial aneurysms.


Assuntos
Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Artéria Carótida Interna , Angiografia Cerebral , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Estudos Retrospectivos , Stents , Resultado do Tratamento
4.
J Stroke Cerebrovasc Dis ; 31(4): 106332, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35151158

RESUMO

The PulseRider (Cerenovus, Johnson & Johnson Medical Devices, New Brunswick, NJ, USA) is a neck reconstruction device that is used for the treatment of unruptured wide-necked bifurcation aneurysms. Herein, we describe the case of a 51-year-old male patient with a basilar apex aneurysm who was treated with PulseRider but had post-procedural brainstem infarctions caused by one of the proximal markers covering the origin of a perforator. In such cases, repositioning of the PulseRider should be performed to avoid infarctions.


Assuntos
Infartos do Tronco Encefálico , Embolização Terapêutica , Procedimentos Endovasculares , Aneurisma Intracraniano , Infartos do Tronco Encefálico/diagnóstico por imagem , Infartos do Tronco Encefálico/etiologia , Infartos do Tronco Encefálico/terapia , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Masculino , Pessoa de Meia-Idade , Stents , Resultado do Tratamento
5.
Pediatr Int ; 63(9): 1095-1102, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33417724

RESUMO

BACKGROUND: Acetylcholinesterase (AChE) histochemistry has been widely performed for the histopathological diagnosis of Hirschsprung's disease (HD). However, we occasionally come across diagnostic difficulties. We conducted concurrent AChE histochemistry and hematoxylin and eosin (HE) staining to validate the ancillary value of this technique. METHODS: Of 177 patients diagnosed using AChE histochemistry from January 2014 to December 2016, 90 patients underwent formalin-fixed paraffin-embedded HE staining. The histopathological findings and diagnostic abilities were investigated and compared retrospectively. RESULTS: The sensitivity, specificity, accuracy, and kappa index of AChE histochemistry and HE staining were 94.1%, 100%, 98.9%, and 0.964 and 76.5%, 84.9%, 83.3%, and 0.530, respectively. The specificity, accuracy and kappa index of AChE histochemistry were significantly higher than those of HE staining (P < 0.001, <0.001, and <0.05). Hematoxylin and eosin staining supported the suspected diagnosis of total colon aganglionosis at the initial biopsy; furthermore, HE staining helped confirm the distinct shape of ganglion cells and hypertrophic nerve bundles. CONCLUSION: We re-confirmed that AChE histochemistry is an excellent method for diagnosing HD. Although the diagnostic ability of HE staining is limited, it has acceptable utility as an ancillary method. Thus, AChE staining is a useful test and it should be performed together with HE staining.


Assuntos
Acetilcolinesterase , Doença de Hirschsprung , Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , Amarelo de Eosina-(YS) , Feminino , Hematoxilina , Doença de Hirschsprung/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Reto , Estudos Retrospectivos , Coloração e Rotulagem , Adulto Jovem
6.
Surg Today ; 51(2): 181-186, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32577882

RESUMO

Hirschsprung's disease (HD) is a congenital disease manifesting various degrees of functional bowel obstruction caused by the absence of enteric ganglion cells, which are usually absent in the colonic segment of the HD patient. Because the aganglionic segment of HD always includes the rectum, pathological diagnosis can be made using a rectal sample. HD should be diagnosed as early as possible because serious complications, such as acute enterocolitis or toxic megacolon, can develop without a definitive diagnosis and appropriate treatment. In the mid-1900s, HD was diagnosed by HE staining of specimens obtained by full-thickness biopsy. Since then, the combination of rectal mucosal biopsy and rubeanic acid-amplificated AChE staining has been brought about by the following milestones: the discovery that the submucosal plexus and the intermuscular plexus had the same level of nerve migration; the findings of research on acetylcholine (ACh) and acetylcholinesterase (AChE) in the intestinal tract; and the establishment of a rubeanic acid amplification method. Consequently, the diagnostic rate of HD improved dramatically in the 1980s. This review outlines the history of diagnostic methods for HD, the roles of ACh and AChE in the intestine, and the method of AChE staining.


Assuntos
Acetilcolinesterase/análise , Doença de Hirschsprung/diagnóstico , Doença de Hirschsprung/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Reto/metabolismo , Reto/patologia , Coloração e Rotulagem/métodos , Biomarcadores/análise , Biópsia/instrumentação , Biópsia/métodos , Humanos , Recém-Nascido , Tioamidas
7.
Asian J Endosc Surg ; 15(1): 235-239, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34008334

RESUMO

INTRODUCTION: Late-onset congenital diaphragmatic hernia constitutes 10%-36% of congenital diaphragmatic hernias. They qualify for endoscopic treatment including both thoracoscopic and laparoscopic approaches because this type of patient is in relatively stable condition compared with neonatal cases. However, single incision laparoscopic approach has not been reported. We herein report an infantile case of late-presenting diaphragmatic hernia who underwent single incision laparoscopic repair using an oval-shaped multichannel port device. MATERIALS AND SURGICAL TECHNIQUE: A 2 month old female infant had sudden onset dyspnea with cyanosis and was diagnosed as having left diaphragmatic hernia (Bochdalek hernia) by chest X-ray. As her respiratory condition became stable under conservative treatment using combination of decompression of the gastrointestinal tract and mild sedation, we electively planned laparoscopic repair. Preoperative enhanced computed tomography imaging found that herniated organs were stomach, spleen, pancreatic tail, small intestine and right colon. The patient also had an umbilical hernia, so we decided to perform single incision repair through this umbilical hernia. Three trocars were introduced using an oval-shaped multichannel port device and herniated organs were reduced by gentle manipulation. The defect of the diaphragm was closed by bi-hand needle driving for upper and lower limb using a stay suture. The umbilical hernia was also repaired. Postoperative course was uneventful and no recurrence was recognized. DISCUSSION: Wider trocar separation was achieved using the oval-shaped device, making the needle driving easier to perform. By using an oval-shaped multichannel port device and ingenuity of needle driving, single incision repair of infant diaphragmatic hernia was enabled.


Assuntos
Hérnia Hiatal , Hérnias Diafragmáticas Congênitas , Laparoscopia , Abdome , Diafragma , Feminino , Hérnias Diafragmáticas Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido
8.
Radiol Case Rep ; 17(1): 115-118, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34777675

RESUMO

Intracranial chondrosarcomas located in the region of the posterior clinoid process have not been focused on. Here, we report the case of a 29-year-old woman with a skull base tumor in that region. Seven years after the diagnosis, the tumor had grown and showed calcification and tumor stain; chondrosarcoma, posterior clinoid meningioma, and chordoma were suspected. The patient underwent subtotal tumor resection, and the histopathological study revealed that the tumor was a low-grade chondrosarcoma. Chondrosarcomas can be located in the region of the posterior clinoid process, and not only chordomas but also posterior clinoid meningiomas should be considered as a differential diagnosis of tumors located in that region, especially when the tumor has calcification or receives a vascular supply.

9.
J Pediatr Surg ; 57(7): 1269-1273, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35393117

RESUMO

BACKGROUND: Immaturity of ganglia (IG), an allied disorder of Hirschsprung disease (AD-HSCR), develops as neonatal ileus, but the dysmotility spontaneously resolves after several months. The diagnosis of IG using HE staining is often difficult. We herein report a new pathological finding of IG called the 'palisading-like pattern', which may be helpful for improving the diagnostic accuracy. METHODS: Cases of IG that were managed over the past 28 years were retrospectively reviewed. We investigated the clinical course and pathological findings for Hematoxylin-Eosin (HE) staining. The conventional diagnostic criteria for IG were (1) a normal or slightly increased number of ganglion cells and (2) ganglion cells with small nuclei. RESULTS: Among the 155 cases, 28 were diagnosed with IG, and 10 were retrospectively confirmed by HE staining. A palisading-like pattern was confirmed at the time of the initial ileostomy (median age, 2.5 days), and the palisading-like pattern had completely disappeared by the time of stoma closure (median age, 215 days) in all 10 cases. A palisading-like pattern is not present in other diseases. CONCLUSIONS: Even if immunostaining data are not available for a further analysis, the detection of a palisading-like pattern on HE staining makes an accurate diagnosis possible. LEVEL OF EVIDENCE: LEVEL IV.


Assuntos
Doença de Hirschsprung , Obstrução Intestinal , Pré-Escolar , Gânglios/patologia , Doença de Hirschsprung/diagnóstico , Doença de Hirschsprung/patologia , Humanos , Ileostomia , Recém-Nascido , Obstrução Intestinal/patologia , Plexo Mientérico/patologia , Estudos Retrospectivos
10.
Cerebrovasc Dis ; 26(4): 388-96, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18753744

RESUMO

BACKGROUND: Our objective was to set up a management-oriented classification for paraclinoid aneurysms, and then design and apply a simplified management scheme according to each group defined by this classification. METHODS: Paraclinoid aneurysms were classified as group I (supraophthalmic artery), group II (ophthalmic artery) and group III (infraophthalmic artery) aneurysms intradurally. Between January 2005 and December 2006, 86 cases with 89 paraclinoid aneurysms were treated. There were 35 (40.2%) aneurysms in group I (20 in group Ia, 15 in group Ib), 32 (36.8%) in group II and 20 (23%) in group III. RESULTS: In group I aneurysms, 20 (57.1%) were treated by clipping or/and wrapping, while 15 (42.9%) were managed by coiling. In group II aneurysms, 20 (62.5%) were treated by clipping and 12 (37.5%) by coiling. The contralateral approach was performed for 4 (6%) aneurysms in groups I and II. All 20 group III aneurysms were treated by coiling. The overall rate of permanent complications was 4.6%. The rate of complete occlusion was 92.5% in surgical cases and 55.6% in endovascular ones. The overall outcomes in the treatment of paraclinoid aneurysms were excellent (GOS = 5, 95.4%). CONCLUSION: Based on our modified classification of paraclinoid aneurysms, a simplified management scheme was designed and applied. For group I (supraophthalmic artery) and group II (ophthalmic artery) aneurysms, surgical clipping or/and wrapping should be the first choice of treatment, while for group III (infraophthalmic artery) aneurysms, endovascular coiling should be the best modality. Additionally, individualizing the treatment planning might contribute to better results.


Assuntos
Embolização Terapêutica , Aneurisma Intracraniano , Procedimentos Neurocirúrgicos/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Idoso , Feminino , Humanos , Aneurisma Intracraniano/classificação , Aneurisma Intracraniano/cirurgia , Aneurisma Intracraniano/terapia , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Artéria Oftálmica/cirurgia , Instrumentos Cirúrgicos
11.
Technol Health Care ; 25(5): 831-842, 2017 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-29103055

RESUMO

BACKGROUND: Stent placement can change the hemodynamics in basilar artery aneurysms. However, the effects of the stent placement can depend on the angle of vessel bifurcation. OBJECTIVE: The hemodynamics in and near the aneurysm are investigated for two angles of vessel bifurcation and two stent models. Some statistical indexes are calculated to evaluate the effects of the stent placements on the possibility of aneurysm rupture. METHODS: Computational fluid dynamics simulations and phantom model experiments are performed. The angle between the basilar and posterior cerebral arteries is set to 90 and 135 degrees. The single stent and Y stent models are tested in addition to the case without stent placement. RESULTS: The velocity in the aneurysm in the Y stent case is smaller than that in the no stent and single stent cases when the angle is 135 degrees. High OSI and low AFI areas often appear at the same locations, and the area is larger in the single stent case than in the no stent and Y stent cases. CONCLUSIONS: The Y stent placement promotes hemostasis and thrombosis in the basilar artery aneurysm, whereas the single stent placement can enhance the growth and rupture.


Assuntos
Artéria Basilar/cirurgia , Hemodinâmica/fisiologia , Aneurisma Intracraniano/cirurgia , Artéria Cerebral Posterior/cirurgia , Stents/normas , Trombose/fisiopatologia , Trombose/cirurgia , Humanos , Guias de Prática Clínica como Assunto
12.
Med Biol Eng Comput ; 54(5): 831-41, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26438390

RESUMO

This paper presents a novel hybrid medical stent device. This hybrid stent device formed by fractal mesh structures provides a flow-diverting effect and stent-assisted coil embolization. Flow-diverter stents decrease blood flow into an aneurysm to prevent its rupture. In general, the mesh size of a flow-diverter stent needs to be small enough to prevent blood flow into the aneurysm. Conventional flow-diverter stents are not available for stent-assisted coil embolization, which is an effective method for aneurysm occlusion, because the mesh size is too small to insert a micro-catheter for coil embolization. The proposed hybrid stent device is capable of stent-assisted coil embolization while simultaneously providing a flow-diverting effect. The fractal stent device is composed of mesh structures with fine and rough mesh areas. The rough mesh area can be used to insert a micro-catheter for stent-assisted coil embolization. Flow-diverting effects of two fractal stent designs were composed to three commercially available stent designs. Flow-diverting effects were analyzed using computational fluid dynamics (CFD) analysis and particle image velocimetry (PIV) experiment. Based on the CFD and PIV results, the fractal stent devices reduce the flow velocity inside an aneurism just as much as the commercially available flow-diverting stents while allowing stent-assisted coil embolization.


Assuntos
Embolização Terapêutica/instrumentação , Fractais , Hemorreologia , Stents , Aneurisma/terapia , Prótese Vascular , Simulação por Computador , Imagens de Fantasmas , Desenho de Prótese , Fluxo Pulsátil
13.
AJNR Am J Neuroradiol ; 26(6): 1366-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15956499

RESUMO

Electrocardiographically (ECG) gated multisection helical CT images were obtained in 23 patients with ruptured intracranial aneurysms. 4D-CTA (3D CT angiography plus phase data) images were generated by ECG-gated reconstruction. Four patients showed pulsation of an aneurysmal bleb. Clipping was performed in two of these patients, and the rupture site matched the pulsatile bleb seen in 4D-CTA.


Assuntos
Angiografia/métodos , Eletrocardiografia , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/fisiopatologia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aneurisma Intracraniano/patologia , Masculino , Pessoa de Meia-Idade , Pulso Arterial
14.
Clin Nucl Med ; 27(9): 633-7, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12192280

RESUMO

PURPOSE: The authors obtained noninvasive quantitative measurements of regional cerebral blood flow using Tc-99m L,L-ethyl cysteinate dimer (Tc-99m ECD) SPECT to evaluate cerebral collateral circulation during balloon test occlusion (BTO) of the internal carotid artery and vertebral artery (VA). METHODS: Five cases associated with an aneurysm and a brain tumor were investigated. After 10 minutes of BTO, a bolus of Tc-99m ECD was injected intravenously and radionuclide angiography was performed. The balloon remained inflated for an additional 5 minutes. After radionuclide angiography was completed, brain SPECT imaging was performed. For quantitative analysis, regions of interest were defined on the transverse images on each side of the anterior cerebral artery and middle cerebral artery territories in cases of occlusion of the internal carotid artery. Regions of interest were defined for the posterior cerebral artery territory and cerebellum in cases of occlusion of the VA. The percentage activity change during BTO was calculated. RESULTS: In two of the three patients in whom BTO of the internal carotid artery was performed, the percentage activity reduction of more than 30% was noted in the anterior cerebral and middle cerebral artery territories. These two patients underwent bypass grafting before carotid occlusion. In one of the two patients in whom BTO of the VA was performed, the percentage activity reduction of 16% was noted in the posterior cerebral artery territory. This patient underwent bypass grafting before occlusion of the VA. CONCLUSION: This noninvasive and quantitative method of cerebral blood flow measurement using Tc-99m ECD during BTO appears to have the potential to help select patients who may tolerate temporary or permanent arterial occlusion.


Assuntos
Oclusão com Balão/métodos , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Cisteína/análogos & derivados , Tomografia Computadorizada de Emissão de Fóton Único , Encéfalo/fisiopatologia , Artéria Carótida Interna/diagnóstico por imagem , Circulação Cerebrovascular , Circulação Colateral , Aneurisma Coronário/diagnóstico por imagem , Aneurisma Coronário/terapia , Feminino , Humanos , Masculino , Neoplasias Meníngeas/irrigação sanguínea , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/irrigação sanguínea , Meningioma/diagnóstico por imagem , Pessoa de Meia-Idade , Compostos de Organotecnécio , Cuidados Pré-Operatórios/métodos , Angiografia Cintilográfica/métodos , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Artéria Vertebral/diagnóstico por imagem
16.
Int J Med Robot ; 9(2): 213-22, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23483681

RESUMO

BACKGROUND: The development of new diagnostic technologies for cerebrovascular diseases requires an understanding of the mechanism behind the growth and rupture of cerebral aneurysms. To provide a comprehensive diagnosis and prognosis of this disease, it is desirable to evaluate wall shear stress, pressure, deformation and strain in the aneurysm region, based on information provided by medical imaging technologies. METHODS: In this research, we propose a new cyber-physical system composed of in vitro dynamic strain experimental measurements and computational fluid dynamics (CFD) simulation for the diagnosis of cerebral aneurysms. A CFD simulation and a scaled-up membranous silicone model of a cerebral aneurysm were completed, based on patient-specific data recorded in August 2008. In vitro blood flow simulation was realized with the use of a specialized pump. A vision system was also developed to measure the strain at different regions on the model by way of pulsating blood flow circulating inside the model. RESULTS: Experimental results show that distance and area strain maxima were larger near the aneurysm neck (0.042 and 0.052), followed by the aneurysm dome (0.023 and 0.04) and finally the main blood vessel section (0.01 and 0.014). These results were complemented by a CFD simulation for the addition of wall shear stress, oscillatory shear index and aneurysm formation index. Diagnosis results using imaging obtained in August 2008 are consistent with the monitored aneurysm growth in 2011. CONCLUSION: The presented study demonstrates a new experimental platform for measuring dynamic strain within cerebral aneurysms. This platform is also complemented by a CFD simulation for advanced diagnosis and prediction of the growth tendency of an aneurysm in endovascular surgery.


Assuntos
Artérias Cerebrais/fisiopatologia , Circulação Cerebrovascular , Aneurisma Intracraniano/fisiopatologia , Modelos Cardiovasculares , Pressão Arterial , Velocidade do Fluxo Sanguíneo , Simulação por Computador , Cibernética/métodos , Módulo de Elasticidade , Dureza , Humanos , Resistência ao Cisalhamento , Resistência à Tração , Resistência Vascular
17.
Asian J Neurosurg ; 7(4): 159-65, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23559981

RESUMO

BACKGROUND: Computer-based simulation is necessary to clarify the hemodynamics in brain aneurysm. Specifically for endovascular treatments, the effects of indwelling intravascular devices on blood stream need to be considered. The most recent technology used for cerebral aneurysm treatment is related to the use of flow diverters to reduce the amount of flow entering the aneurysm. To verify the differences of flow reduction, we analyzed multiple Enterprise stents and two kinds of flow diverters. MATERIALS AND METHODS: In this research, we virtually modeled three kinds of commercial intracranial stents (Enterprise, Silk, and Pipeline) and mounted to fit into the vessel wall, and deployed across the neck of an IC-ophthalmic artery aneurysm. Also, we compared the differences among multiple Enterprise stents and two flow diverters in a standalone mode. RESULTS: From the numerical results, the values of wall shear stress and pressure are reduced in proportion to the size of mesh, especially in the inflow area. However, the reduced velocity within the aneurysm sac by the multiple stents is not as significant as the flow diverters. CONCLUSIONS: This is the first study analyzing the flow alterations among multiple Enterprise stents and flow diverters. The placement of small meshed stents dramatically reduced the aneurysmal fluid movement. However, compared to the flow diverters, we did not observe the reduction of flow velocity within the aneurysm by the multiple stents.

18.
Asian J Neurosurg ; 7(3): 109-15, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23293665

RESUMO

Hemodynamic factors are thought to play important role in the initiation, growth, and rupture of cerebral aneurysms. However, hemodynamic features in the residual neck of incompletely occluded aneurysms and their influences on recanalization are rarely reported. This study characterized the hemodynamics of incompletely occluded aneurysms that had been confirmed to undergo recanalization during long-term follow-up using computational fluid dynamic analysis. A ruptured left basilar-SCA aneurysm was incompletely occluded and showed recanalization during 11 years follow-up period. We retrospectively characterized on three-dimensional MR angiography. After subtotal occlusion, the flow pattern, wall shear stress (WSS), and velocity at the remnant neck changed during long-term follow-up period. Specifically, high WSS region and high blood flow velocity were found near the neck. Interestingly, these area of the remnant neck coincided with the location of aneurysm recanalization. High WSS and blood flow velocity were consistently observed near the remnant neck of incompletely occluded aneurysm, prone to future recanalization. It will suggest that hemodynamic factors may play important roles in aneurismal recurrence after endovascular treatment.

19.
Asian J Neurosurg ; 6(1): 45-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22059104

RESUMO

Carotid cavernous fistula (CCF) is an abnormal arteriovenous communication in the cavernous sinus. Direct CCF results from a tear in the intracavernous carotid artery. Typically, it has a high flow and usually presents with oculo-orbital venous congestive features such as exophthalmos, chemosis, and sometimes oculomotor or abducens cranial nerve palsy. Indirect CCF generally occurs spontaneously with subtle signs. We report a rare case of spontaneous direct CCF in childhood who did not have the usual history of craniofacial trauma or connective tissue disorder but presented with progressive chemosis and exophthalmos of the right eye. This report aims also to describe the safety and success of transvenous embolization with coils of the superior ophthalmic vein and cavernous sinus through the inferior petrosal sinus.

20.
Cerebrovasc Dis ; 23(5-6): 381-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17406106

RESUMO

BACKGROUND: A limited series of patients with aneurysm were reviewed retrospectively to analyze strategies for integrating microsurgical and endovascular techniques in the management of complex, surgically intractable aneurysms. METHODS: Four patients were managed in Fujita Health University with a multimodality approach: intentional reconstruction of the aneurysm neck followed by endovascular coiling. RESULTS: A total of 5 aneurysms were treated, of which 3 were large or giant in size, and 3 were fusiform or multilobulated. Complete angiographic obliteration was confirmed in 4 aneurysms (80%). All patients had a good outcome (Glasgow Outcome Scale score 5; mean follow-up, 64 months). CONCLUSION: As for complex, surgically intractable aneurysms, the intentional reconstruction of the aneurysm neck followed by endovascular coiling should be considered more often.


Assuntos
Revascularização Cerebral , Embolização Terapêutica , Aneurisma Intracraniano/terapia , Adulto , Velocidade do Fluxo Sanguíneo , Angiografia Cerebral , Revascularização Cerebral/instrumentação , Circulação Cerebrovascular , Feminino , Humanos , Aneurisma Intracraniano/patologia , Aneurisma Intracraniano/fisiopatologia , Aneurisma Intracraniano/cirurgia , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Instrumentos Cirúrgicos , Resultado do Tratamento , Grau de Desobstrução Vascular
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