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1.
Neurosurgery ; 63(3): 571-8; discussion 578, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18812969

RESUMO

OBJECTIVE: Using ribonucleic acid interference on cultured cell lines, we examined the role of Krev interaction trapped 1 (krit1) and integrin cytoplasmic domain-associated protein-1 alpha (icap1alpha) in beta1-integrin-mediated cell proliferation. METHODS: Upon depletion of either krit1 or icap1alpha in the HeLa cells, umbilical vein endothelial cells, and microvascular endothelial cells, we examined the cell number and proliferation changes in the cells, followed by the evaluation of beta1-integrin-mediated mitogen-activated protein kinase signal pathway and microscopic study. RESULTS: Depletion of krit1 reduces cell number and decreases endothelial cell proliferation. Examination of beta1-integrin signaling downstream of focal adhesion kinase reveals decreased phosphorylation along the extracellular signal-regulated kinase/mitogen-activated protein kinase pathway. Depletion of icap1alpha, a protein known to interact with krit1, has similar effects, suggesting synergistic function. We also show that krit1 colocalizes with icap1alpha in both the nucleus and the cytoplasm; however, most of icap1alpha is found in the nucleus and most of krit1 is found in the cytoplasm at steady state. On depletion of krit1, icap1alpha decreases in the cytoplasm and is no longer detected in the nucleus. CONCLUSION: Both krit1 and icap1alpha act concordantly to play a critical role in beta1-integrin-mediated cell proliferation. Our data further suggest that krit1 both stabilizes and shuttles icap1alpha and thus modulates its regulation of beta1-integrin-mediated signal transduction.


Assuntos
Proliferação de Células , Células Endoteliais/fisiologia , Integrina beta1/fisiologia , Proteínas Associadas aos Microtúbulos/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Células Cultivadas , Citoplasma/química , Citoplasma/metabolismo , Células Endoteliais/citologia , Células HeLa , Humanos , Integrina beta1/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Proteína KRIT1 , Sistema de Sinalização das MAP Quinases/genética , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Proteínas Associadas aos Microtúbulos/genética , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/genética
2.
Comput Aided Surg ; 13(1): 41-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18240054

RESUMO

OBJECTIVE: Microsurgery for the clipping of cerebral aneurysms requires a working knowledge of the anatomy of the cerebral vasculature and its relationship to landmarks on the surface of the brain and along the skull base. However, for more distally located aneurysms of the anterior cerebral artery (ACA), locating the lesion can prove frustrating and may require much more extensive interhemispheric dissection than is otherwise needed for proximal control, exposure of the aneurysm, and clip application. We report a case series of five patients in which frameless stereotaxy and CT angiographic data sets were used to minimize the extent of surgery required to clip distal ACA aneurysms. CLINICAL PRESENTATIONS: Five patients were found to have distal ACA aneurysms during the work-up of subarachnoid hemorrhage or other neurologic symptoms. The patients comprised two with subarachnoid hemorrhage, one with dizziness, one with stroke, and one with migraines and polycystic kidney disease. Each patient was found to have an aneurysm at the pericallosal/callosal marginal junction. INTERVENTION: All five patients underwent a right parasagittal craniotomy and clipping of a distal ACA aneurysm. The location of the craniotomy and subsequent interhemispheric dissection were guided by CT angiographic data sets and computer-assisted frameless stereotaxy. CONCLUSION: Frameless stereotaxy using a CT angiographic data set is a useful adjunct to routine microsurgery in the clipping of distal ACA aneurysms. Its use obviates the need for extensive interhemispheric dissection, allows the surgeon to gain proximal control and expose the aneurysm more efficiently, and should minimize complications related to unwitting aneurysm exposure.


Assuntos
Dissecção Aórtica/cirurgia , Aneurisma Intracraniano/cirurgia , Técnicas Estereotáxicas/instrumentação , Idoso , Dissecção Aórtica/patologia , Angiografia , Hemorragia Cerebral/cirurgia , Craniotomia/instrumentação , Feminino , Humanos , Aneurisma Intracraniano/patologia , Microcirurgia/instrumentação , Pessoa de Meia-Idade , Acidente Vascular Cerebral , Hemorragia Subaracnóidea/cirurgia
3.
J Neurosurg ; 107(6): 1080-5, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18077943

RESUMO

OBJECT: The authors of previous studies have shown that admission hyperglycemia or perioperative hyperglycemic events may predispose a patient to poor outcome after aneurysmal subarachnoid hemorrhage (SAH). The results of experimental evidence have suggested that hyperglycemia may exacerbate ischemic central nervous system injury. It remains to be clarified whether a single hyperglycemic event or persistent hyperglycemia is predictive of poor outcome after aneurysmal SAH. METHODS: Ninety-seven patients undergoing treatment for aneurysmal SAH were observed, and all perioperative variables were entered into a database of prospectively recorded data. Daily serum glucose values were retrospectively added. Patients were examined at hospital discharge (14-21 days after SAH onset), and Glasgow Outcome Scale (GOS) scores were prospectively documented. The GOS score at last follow-up was retrospectively determined. Serum glucose greater than 200 mg/dl for 2 or more consecutive days was defined as persistent hyperglycemia. Outcome was categorized as "poor" (dependent function [GOS Score 1-3]) or "good" (independent function [GOS Score 4 or 5]) at discharge. The independent association of 2-week and final follow-up outcome (GOS score) with the daily serum glucose levels was assessed using a multivariate analysis. RESULTS: In the univariate analysis, increasing age, increasing Hunt and Hess grade, hypertension, ventriculomegaly on admission computed tomography scan, Caucasian race, and higher mean daily glucose levels were associated with poor (dependent) 2-week outcome after aneurysmal SAH. In the multivariate analysis, older age, the occurrence of symptomatic cerebral vasospasm, increasing admission Hunt and Hess grade, and persistent hyperglycemia were independent predictors of poor (dependent) outcome 2 weeks after aneurysmal SAH. Admission Hunt and Hess grade and persistent hyperglycemia were independent predictors of poor outcome at last follow-up examination a mean 10 +/- 3 months after aneurysmal SAH. Isolated hyperglycemic events did not predict poor outcome. Patients with persistent hyperglycemia were 10-fold more likely to have a poor (dependent) 2-week outcome and sevenfold more likely to have a poor outcome a mean 10 months after aneurysmal SAH independent of admission Hunt and Hess grade, occurrence of cerebral vasospasm, or all comorbidities. CONCLUSIONS: Patients with persistent hyperglycemia were seven times more likely to have a poor outcome at a mean of 10 months after aneurysmal SAH. Isolated hyperglycemic events were not predictive of poor outcome. Serum glucose levels in the acute setting of aneurysmal SAH may help predict outcomes months after surgery.


Assuntos
Hiperglicemia/etiologia , Hiperglicemia/fisiopatologia , Aneurisma Intracraniano/complicações , Procedimentos Neurocirúrgicos , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/cirurgia , Adulto , Fatores Etários , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Valor Preditivo dos Testes , Prognóstico , Índice de Gravidade de Doença , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Vasoespasmo Intracraniano/complicações , Vasoespasmo Intracraniano/etiologia
4.
Surg Neurol ; 68(4): 443-8; discussion 448, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17905071

RESUMO

BACKGROUND: Anterior sacral meningocele is a rare congenital malformation, whose open surgical treatment is well accepted. We present a laparoscopic approach as an adjunctive approach. METHODS: Five women who underwent laparoscopic transperitoneal surgery were clinically, radiologically, and surgically evaluated. RESULT: All 5 patients underwent laparoscopic transperitoneal surgery and showed satisfactory results. They had no major complications. Three patients had headaches as minor complications, but it was gone in at most 3 days. Decrease in operative time, blood loss, and length of hospitalization were the advantages of the procedure. CONCLUSIONS: The laparoscopic approach to treating anterior sacral meningocele was feasible and safe, with only minor complications.


Assuntos
Laparoscopia/métodos , Meningocele/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Anestesia Geral , Perda Sanguínea Cirúrgica , Feminino , Cefaleia/epidemiologia , Cefaleia/etiologia , Humanos , Laparoscopia/efeitos adversos , Imageamento por Ressonância Magnética , Síndrome de Marfan/complicações , Meninges/anatomia & histologia , Meninges/cirurgia , Meningocele/diagnóstico por imagem , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Tomografia Computadorizada por Raios X
5.
Neuroradiology ; 49(8): 665-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17558502

RESUMO

We present a novel access for transvenous embolization of a dural arteriovenous fistula of the laterocavernous sinus through the external jugular vein and the pterygoid plexus. The anatomy of the laterocavernous sinus is reviewed, and its clinical implications discussed in light of the case of a patient whose management was modified after identifying this anatomical variation.


Assuntos
Seio Cavernoso , Malformações Vasculares do Sistema Nervoso Central/terapia , Embolização Terapêutica/métodos , Seio Cavernoso/anatomia & histologia , Feminino , Humanos , Pessoa de Meia-Idade
6.
Neurosurgery ; 60(2): 353-9; discussion 359, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17290187

RESUMO

OBJECTIVE: Cerebral cavernous malformations (CCM) are a relatively common autosomal dominant disorder leading to the formation of vascular malformations in the nervous system. Mutations in krit1 and malcavernin, the proteins encoded by the genes at the CCM1 and CCM2 loci, respectively, are responsible for the majority of CCMs. Similar to integrin cytoplasmic domain-associated protein-1alpha, a known krit1 interactor, malcavernin is a phosphotyrosine binding protein. We report here that krit1 also interacts with malcavernin. METHODS: We used two-hybrid analysis, in vivo coimmunoprecipitation, and epitope mapping to explore the interaction between krit1 and malcavernin. Immunocytochemistry was used to study the cellular localization of these proteins. RESULTS: We demonstrate that malcavernin independently binds to two of the three NPXY (asparagine, proline, undetermined/variable amino acid, and tyrosine) motifs in krit1. By immunocytochemistry, malcavernin protein is cytoplasmic at steady state, but shuttles between the nucleus and cytoplasm, despite lacking either a nuclear localization signal or a nuclear export signal in its sequence. CONCLUSION: These data suggest that krit1 interacts with malcavernin through its NPXY motifs and may shuttle it through the nucleus via its nuclear localization signal and nuclear export signals, thereby regulating its cellular function.


Assuntos
Malformações Vasculares do Sistema Nervoso Central/etiologia , Malformações Vasculares do Sistema Nervoso Central/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Animais , Células COS , Malformações Vasculares do Sistema Nervoso Central/patologia , Chlorocebus aethiops , Células HeLa , Humanos , Proteína KRIT1 , Proteínas dos Microfilamentos/genética , Proteínas Associadas aos Microtúbulos/genética , Proteínas Proto-Oncogênicas/genética
7.
Neurosurgery ; 59(4 Suppl 2): ONS347-51; discussion ONS351-2, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17041503

RESUMO

OBJECTIVE: Complex aneurysms arising at the middle cerebral artery (MCA) bifurcation frequently present a microsurgical challenge to effectively obliterate while maintaining patency of the distal MCA branches. These aneurysms are often multilobed, with their long axis aligned with the long axis of the M1 trunk, placing the dome of the aneurysm in the surgeons' line of sight, preventing an unobstructed view of the entire bifurcation and proximal M1 segment. MCA aneurysms often have a broad neck, splaying the bifurcation. An orthogonal interlocking tandem clipping technique, maximizing the use of fenestrated aneurysm clips, is presented as a means to completely obliterate the aneurysm and simultaneously "reconstruct" the MCA bifurcation. CLINICAL PRESENTATIONS AND INTERVENTION: Fifteen complex MCA aneurysms were treated using an interlocking tandem clipping technique. In its simplest application, the blades of the initial aneurysm clip are incorporated into the fenestration of the second clip. Obliteration of the residual aneurysm is achieved with the blades of the second, fenestrated clip. RESULTS: Satisfactory aneurysm obliteration and reconstruction of the MCA bifurcation was achieved in all cases using this technique, with excellent neurological outcomes. CONCLUSION: Morphologically complex multilobed MCA aneurysms can be effectively clipped with "reconstruction" of the normal vascular anatomy using a tandem interlocking clipping technique. A fenestrated clip is used to incorporate the blades of the initial clip, while obliterating the remainder of the aneurysm.


Assuntos
Aneurisma Intracraniano/cirurgia , Procedimentos de Cirurgia Plástica/instrumentação , Procedimentos de Cirurgia Plástica/métodos , Instrumentos Cirúrgicos , Procedimentos Cirúrgicos Vasculares/instrumentação , Procedimentos Cirúrgicos Vasculares/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Resultado do Tratamento
8.
J Neurosurg ; 105(2 Suppl): 134-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16922075

RESUMO

Ionizing radiation therapy is associated with pathological vascular changes in intracranial vessels, most commonly in the form of vessel thrombosis and occlusion. The development of an intracranial aneurysm following such therapy, however, is far less common. In this report the authors describe a 24-year-old man in whom a distal middle cerebral artery aneurysm developed 15 years after radiotherapy, which was given as adjuvant treatment following resection of a medulloblastoma. The patient underwent a craniotomy for microsurgical trapping of the aneurysm and was discharged without any neurological deficit. This case serves to remind clinicians of the possibility, albeit rare, that intracranial aneurysms may form following cranial radiotherapy.


Assuntos
Neoplasias Cerebelares/radioterapia , Aneurisma Intracraniano/etiologia , Meduloblastoma/radioterapia , Radioterapia/efeitos adversos , Adulto , Angiografia Cerebral , Humanos , Aneurisma Intracraniano/cirurgia , Imageamento por Ressonância Magnética , Masculino , Artéria Cerebral Média/patologia , Artéria Cerebral Média/cirurgia
9.
Neurosurgery ; 58(6): 1066-73; discussion 1066-73, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16723885

RESUMO

OBJECTIVE: Clinical and experimental evidence suggests that hyperglycemia lowers the neuronal ischemic threshold, potentiates stroke volume in focal ischemia, and is associated with morbidity and mortality in the surgical critical care setting. It remains unknown whether hyperglycemia during carotid endarterectomy (CEA) predisposes patients to perioperative stroke and operative related morbidity and mortality. METHODS: The clinical and radiological records of all patients undergoing CEA and operative day glucose measurement from 1994 to 2004 at an academic institution were reviewed and 30-day outcomes were assessed. The independent association of operative day glucose before CEA and perioperative morbidity and mortality were assessed via multivariate logistic regression analysis. RESULTS: One thousand two hundred and one patients with a mean age of 72 +/- 10 years (748 men, 453 women) underwent CEA (676 asymptomatic, 525 symptomatic). Overall, stroke occurred in 46 (3.8%) patients, transient ischemic attack occurred in 19 (1.6%), myocardial infarction occurred in 19 (1.6%), and death occurred in 17 (1.4%). Increasing operative day glucose was independently associated with perioperative stroke or transient ischemic attack (Odds ratio [OR], 1.005; 95% confidence interval [CI], 1.00-1.01; P = 0.03), myocardial infarction (OR, 1.01; 95% CI, 1.004-1.016; P = 0.017), and death (OR, 1.007; 95% CI, 1.00-1.015; P = 0.04). Patients with operative day glucose greater than 200 mg/dl were 2.8-fold, 4.3-fold, and 3.3-fold more likely to experience perioperative stroke or transient ischemic attack (OR, 2.78; 95% CI, 1.37-5.67; P = 0.005), myocardial infarction (OR, 4.29; 95% CI, 1.28-14.4; P = 0.018), or death (OR, 3.29; 95% CI, 1.07-10.1; P = 0.037), respectively. Median and interquartile range length of hospitalization was greater for patients with operative day glucose greater than 200 mg/dl (4 d [interquartile range, 2-15 d] versus 3 d [interquartile range, 2-7 d]; P < 0.05). CONCLUSION: Independent of previous cardiac disease, diabetes, or other comorbidities, hyperglycemia at the time of CEA was associated with an increased risk of perioperative stroke or transient ischemic attack, myocardial infarction, and death. Strict glucose control should be attempted before surgery to minimize the risk of morbidity and mortality after CEA.


Assuntos
Estenose das Carótidas/complicações , Estenose das Carótidas/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Endarterectomia das Carótidas/mortalidade , Hiperglicemia/complicações , Infarto do Miocárdio/etiologia , Acidente Vascular Cerebral/etiologia , Idoso , Feminino , Humanos , Incidência , Ataque Isquêmico Transitório/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/epidemiologia , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
10.
Neurosurgery ; 58(5): 945-51; discussion 945-51, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16639331

RESUMO

OBJECTIVE: Experimental evidence suggests that intercellular adhesion molecule-1 mediated leukocyte extravasation contributes to the pathogenesis of cerebral vasospasm. Simvastatin, an HMG-CoA reductase inhibitor, decreases intercellular adhesion molecule-1 expression and competitively inhibits leukocyte intercellular adhesion molecule-1 binding. We hypothesized that administration of simvastatin after the onset of subarachnoid hemorrhage (SAH) would attenuate perivascular granulocyte migration and ameliorate cerebral vasospasm in a rabbit model of SAH. METHODS: New Zealand white rabbits (n = 15) underwent injection of autologous blood into the cisterna magna or sham surgery followed by subcutaneous injection of simvastatin (40 mg/kg) or vehicle 30 minutes, 24 hours, and 48 hours after SAH or sham surgery. Seventy-two hours later, basilar artery lumen diameter was measured by in situ perfusion/fixation and image analysis. CD-18 monoclonal antibody stained perivascular granulocytes and macrophages were counted under light microscopy. RESULTS: In vehicle treated rabbits, mean +/- standard deviation basilar artery diameter was reduced 3 days after SAH (n = 5) versus sham (n = 5) rabbits (0.49 +/- 0.08 mm versus 0.75 +/- 0.03 mm, P < 0.01). After SAH, mean +/- standard deviation basilar artery diameter was greater in simvastatin (n = 5) treated rabbits versus vehicle (n = 5) (0.63 +/- 0.04 mm versus 0.49 +/- 0.08 mm, P < 0.01). In vehicle treated rabbits, SAH resulted in an increase in the mean +/- standard deviation perivascular CD18 cell count (sham-vehicle, 2.8 +/- 2; SAH-vehicle 90 +/- 27; P < 0.01). Subcutaneous administration of simvastatin attenuated this increase in perivascular CD18-positive cells after SAH (SAH statin, 41.6 +/- 13; SAH vehicle, 90 +/- 27; P < 0.001). CONCLUSION: Subcutaneous administration of simvastatin after the onset of SAH attenuates perivascular granulocyte migration and ameliorates basilar artery vasospasm after experimental SAH in rabbits. 5-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, such as simvastatin, may potentially serve as agents in the prevention of cerebral vasospasm after SAH.


Assuntos
Sinvastatina/administração & dosagem , Hemorragia Subaracnóidea/patologia , Vasoespasmo Intracraniano/patologia , Vasoespasmo Intracraniano/prevenção & controle , Animais , Movimento Celular/efeitos dos fármacos , Coelhos , Hemorragia Subaracnóidea/complicações , Vasoespasmo Intracraniano/etiologia
11.
Neurosurgery ; 58(5): 952-60; discussion 952-60, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16639332

RESUMO

OBJECTIVE: Diethylenetriamine/nitric oxide (DETA/NO) has been shown to be an effective treatment for delayed posthemorrhagic vasospasm when released abluminally from ethylene-vinyl acetate copolymer (EVAc). However, the observed mortality associated with this drug warrants further investigation. To establish a maximum tolerable dose, this study evaluated the toxicity of DETA/NO released from EVAc in a dose-escalation series in cynomolgus monkeys (Macaca fascicularis). METHODS: DETA/NO was incorporated into EVAc at a 20:80 dry weight ratio (DETA/NO:EVAc). A total of 13 animals underwent a right frontotemporal craniotomy for placement of a single polymer delivering no drug (n = 3), 0.5 +/- 0.1 mg/kg (n = 3), 0.9 +/- 0.1 mg/kg (n = 3), 1.9 +/- 0.2 mg/kg (n = 3), or a 3.2 mg/kg dose (n = 1) into the subarachnoid space. RESULTS: The animal receiving the highest dose of DETA/NO (3.2 mg/kg) died 46 hours after surgery. The remaining animals survived for the planned duration of the study. One animal in the group receiving the 1.9 mg/kg dose experienced a seizure 25 hours after surgery and remained lethargic for 2 days before making a complete recovery. The remaining animals exhibited no adverse behavioral effects. Histopathological examination of brain tissue revealed hemorrhagic and ischemic changes at doses above 0.9 mg/kg. No evidence of vascular wall pathology or infection was observed in any animal. CONCLUSION: The greatest amount of DETA/NO safely delivered from EVAc copolymer to the subarachnoid space of the cynomolgus monkey is approximately 1.0 mg/kg. These findings show that continuous intracisternal delivery of DETA/NO is a safe and potentially effective strategy for prophylactic treatment of delayed cerebral vasospasm.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Doadores de Óxido Nítrico/administração & dosagem , Polímeros/administração & dosagem , Triazenos/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Preparações de Ação Retardada/administração & dosagem , Macaca fascicularis , Masculino , Espaço Subaracnóideo/efeitos dos fármacos
12.
J Neurosurg ; 103(4): 745-51, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16266059

RESUMO

OBJECT: Results of prior studies in rats and rabbits show that the alteration of vasomotor tone in vasospasm following periadventitial blood exposure may be reversed, at least in part, by the administration of compounds releasing nitric oxide (NO). The authors have now generalized this finding to nonhuman primates. METHODS: Ten cynomolgus monkeys underwent cerebral angiography before and 7 days following the induction of subarachnoid hemorrhage (SAH) by the placement of 2 to 3 ml clotted autologous blood around the supraclinoid carotid, proximal anterior cerebral, and proximal middle cerebral arteries. An ethylene vinyl acetate copolymer, either blank (five animals) or containing 20% w/w (Z)-1-[2-(2-aminoethyl)-N-(2-aminoethyl)amino]diazen-1-ium-1,2-diolate (DETA/NO, 4.3 mg/kg; five animals) was placed adjacent to the vessels at the time of surgery. Animals were killed on Day 7 post-SAH following repeated cerebral angiography. The mean percentage of control vascular areal fraction was calculated from angiograms. Cerebral vessels were sectioned and the mean percentage of lumen patency was calculated. One animal that had received the DETA/NO polymer died prior to repeated angiography. In the remaining animals, DETA/NO caused a significant decrease in vasospasm compared with controls, according to both angiographic (84.8 +/- 8.6 compared with 56.6 +/- 5.2%, respectively, p < 0.05) and histological studies (internal carotid artery 99.3 +/- 1.8 compared with 60.1 +/- 4.4%, respectively, p < 0.001; middle cerebral artery 98.4 +/- 3 compared with 56.1 +/- 3.7%, respectively, p < 0.001; and anterior cerebral artery 89.2 +/- 8.5 compared with 55.8 +/- 6.3%, respectively, p < 0.05). CONCLUSIONS: The controlled release of DETA/NO is effective in preventing delayed cerebral vasospasm in an SAH model in nonhuman primates. The death of one animal in the treatment group indicates that the present dosage is at the threshold between therapeutic efficacy and toxicity.


Assuntos
Hemorragia Subaracnóidea/complicações , Triazenos/administração & dosagem , Triazenos/farmacologia , Vasoespasmo Intracraniano/prevenção & controle , Animais , Angiografia Cerebral/veterinária , Preparações de Ação Retardada , Macaca fascicularis , Masculino , Doadores de Óxido Nítrico , Polivinil , Hemorragia Subaracnóidea/veterinária , Fatores de Tempo , Vasoespasmo Intracraniano/fisiopatologia , Vasoespasmo Intracraniano/veterinária
13.
Surg Neurol ; 64(4): 321-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16229089

RESUMO

BACKGROUND: Digital subtraction angiography (DSA) is considered the gold standard in the evaluation of cerebrovascular structures. Recently, 3-dimensional DSA (3D-DSA) has been increasingly used to obtain detailed information about the morphology and dimensions of intracranial aneurysms. We report the case of a patient who presented with a distal pericallosal artery aneurysm, which appeared by 2D imaging to be a fusiform, possible mycotic aneurysm. This was then revealed to be a saccular bifurcation aneurysm by 3D-DSA. This additional information changed the treatment plan for this patient from medical management to a surgical approach. CASE DESCRIPTION: The patient is a 56-year-old man with a history of hypertension and alcohol abuse with withdrawal seizures, who presented with a large intracranial hemorrhage on initial computed tomography scan. After stabilization with intracranial pressure management, the patient underwent magnetic resonance angiography and 4-vessel DSA. These initial studies showed a distal, fusiform pericallosal aneurysm consistent with a mycotic aneurysm. Rotational DSA was then used to generate 3D images of the structure that revealed a saccular bifurcation aneurysm. This enabled the decision to offer operative treatment rather than conservative medical management. DISCUSSION: This report highlights the value of 3D-DSA in establishing the appropriate treatment plan for patients with unique cerebral aneurysms. The higher resolution images used in this case provided information that was crucial in shifting the treatment focus from medical management, for what appeared to be a mycotic aneurysm by traditional DSA, to surgical intervention, for a clear hemodynamic aneurysm at a vessel bifurcation seen with 3D-DSA. Accurate pre-interventional evaluation and differential diagnosis are critical to designing the most effective lowest risk treatment plan. The standard method in the diagnosis of cerebral aneurysms has been DSA. Yet, higher resolution images of unclear or high-risk aneurysms are often required to guide clinical decision making. The emergence of new, less invasive endovascular techniques for securing intracranial aneurysms has placed greater emphasis on precisely defining the shape and dimensions of an aneurysm. Three-dimensional DSA is currently the highest resolution imaging modality available for the evaluation of intracranial aneurysms. CONCLUSION: 3D-DSA was used to evaluate a small, distal pericallosal artery aneurysm and revealed a saccular bifurcation aneurysm not visualized with magnetic resonance angiography and conventional DSA. This additional resolution permitted the team to consider a surgical approach for a patient who would otherwise have been treated medically. This high-resolution technique is particularly useful in guiding clinical decision making in the context of aneurysms that carry a relatively broad differential diagnosis, potentially high interventional risk, and unclear morphology.


Assuntos
Angiografia Digital/métodos , Artéria Cerebral Anterior/diagnóstico por imagem , Artéria Cerebral Anterior/patologia , Imageamento Tridimensional , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Convulsões por Abstinência de Álcool , Alcoolismo/complicações , Angiografia Digital/normas , Artéria Cerebral Anterior/cirurgia , Corpo Caloso/irrigação sanguínea , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Humanos , Hipertensão/complicações , Processamento de Imagem Assistida por Computador/métodos , Aneurisma Intracraniano/cirurgia , Hemorragia Intracraniana Hipertensiva/etiologia , Masculino , Pessoa de Meia-Idade
14.
Neurosurgery ; 57(1 Suppl): 160-3; discussion 160-3, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15987583

RESUMO

Not infrequently, patients with bilateral cerebral aneurysms are encountered. In such patients, the ability to treat bilateral aneurysms through a unilateral approach spares the patient the risk and inconvenience associated with a separate craniotomy. The contralateral approach for aneurysm repair is technically feasible and safe in appropriately selected patients. Herein, we review our technique for maximizing contralateral exposure and clipping contralateral aneurysms through the four anatomic triangles that serve as corridors in this approach.


Assuntos
Aneurisma Intracraniano/cirurgia , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Medição de Risco/métodos , Humanos , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Prognóstico , Fatores de Risco , Resultado do Tratamento
15.
Neurosurgery ; 57(1 Suppl): 164-7; discussion 164-7, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15987584

RESUMO

Arteriovenous malformations are a heterogeneous group of intra-axial central nervous system vascular lesions consisting of tangles of abnormal arteriovenous connections without intervening capillary beds. The heterogeneity of arteriovenous malformations is described by the Spetzler-Martin grading scale, a scale that also forms the basis for clinical decision making. The microsurgical treatment of appropriately selected supratentorial arteriovenous malformations is based on the tenets of circumferential isolation and transection of arterial feeders, preservation of vessels en passant and surrounding functional neural tissue, and skeletonization and transection of venous drainage.


Assuntos
Encéfalo/cirurgia , Malformações Arteriovenosas Intracranianas/diagnóstico , Malformações Arteriovenosas Intracranianas/cirurgia , Microcirurgia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Neurocirúrgicos/métodos , Medição de Risco/métodos , Humanos , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Prognóstico , Fatores de Risco , Resultado do Tratamento
16.
Neurosurgery ; 57(1 Suppl): 184-90; discussion 184-90, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15987587

RESUMO

OBJECTIVE: Adhesion and migration of leukocytes into the periadventitial space play a role in the pathophysiology of vasospasm after subarachnoid hemorrhage (SAH). Intercellular adhesion molecule-1 is a determinant cell adhesion molecule involved in this process. Ibuprofen has been shown to inhibit intercellular adhesion molecule-1 upregulation and prevent vasospasm in animal models of SAH. In this study, we report the toxicity and efficacy of locally delivered ibuprofen incorporated into controlled-release polymers to prevent vasospasm in a monkey model of SAH. METHODS: Ibuprofen was incorporated into ethylene-vinyl acetate (EVAc) polymers at 45% loading (wt:wt). For the toxicity study, cynomolgus monkeys (n = 5) underwent surgical implantation of either blank/EVAc polymers (n = 3) or 45% ibuprofen/EVAc polymers (n = 2) in the subarachnoid space, were followed up for 13 weeks, and were killed for histopathological analysis. For the efficacy study, cynomolgus monkeys (n = 14) underwent cerebral angiography 7 days before and 7 days after surgery and SAH and were randomized to receive either a 45% ibuprofen/EVAc polymer (n = 7; mean dose of ibuprofen, 6 mg/kg) or blank EVAc polymers (n = 7) in the subarachnoid space. Angiographic vasospasm was determined by digital image analysis. Student's t test was used for analysis. RESULTS: Animals implanted with ibuprofen polymers showed no signs of local or systemic toxicity. Animals treated with ibuprofen polymers had 91 +/- 9% lumen patency of the middle cerebral artery, compared with 53 +/- 11% of animals treated with blank/EVAc polymers (P < 0.001). CONCLUSION: Ibuprofen polymers are safe and prevent angiographic vasospasm after SAH in the monkey model. These findings support the role of cell adhesion molecules and inflammation in the pathophysiology of vasospasm.


Assuntos
Preparações de Ação Retardada/administração & dosagem , Modelos Animais de Doenças , Ibuprofeno/administração & dosagem , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/prevenção & controle , Animais , Angiografia Cerebral , Preparações de Ação Retardada/efeitos adversos , Ibuprofeno/efeitos adversos , Macaca fascicularis , Masculino , Veículos Farmacêuticos/administração & dosagem , Veículos Farmacêuticos/efeitos adversos , Polivinil , Resultado do Tratamento , Vasoespasmo Intracraniano/diagnóstico por imagem
18.
Neurosurgery ; 56(1 Suppl): 172-7; discussion 172-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15799807

RESUMO

Basilar apex region aneurysms are among the most complex cerebral aneurysms. They are not, however, among the most common aneurysms, and increased use of endovascular treatment has further decreased the number of patients with these lesions who undergo surgery. Nonetheless, not all basilar apex aneurysms are amenable to coil embolization, and neurosurgeons must be prepared to treat patients with basilar apex aneurysms surgically. We prefer an orbitozygomatic craniotomy and transsylvian approach. Meticulous exercise of the basic tenets of aneurysm surgery (proximal vascular control, sharp dissection, and preservation of perforating vessels) is crucial to optimal patient outcomes.


Assuntos
Craniotomia/métodos , Aneurisma Intracraniano/cirurgia , Microcirurgia/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Humanos , Aneurisma Intracraniano/fisiopatologia
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