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1.
Artigo em Inglês | MEDLINE | ID: mdl-24109835

RESUMO

Frozen section studies are a useful method to rapidly define tumor malignancy and identify the extent of surgical resection. However, diagnosis with a frozen section is qualitative and sometimes difficult. Therefore a quantitative method for grading tumors is desired. We have already reported a technique of intraoperative flow cytometry (iFC) that supports intraoperative histopathological examination of frozen sections. In this study, we report an advanced system named "Fully Automatic Rapid DNA Ploidy Analyzer" with a tissue pretreatment function and a freeze-dried reagent kit for cell staining. To evaluate our system, we analyzed samples from glioma patients who underwent open surgery for brain tumors. We observed obvious difference of the Malignancy Index (MI) between neoplastic and perilesional brain tissue (26.0 ±22.1% and 4.1 ±2.5%, respectively, P<0.001). Cut-off level for identification of the tumor in the biopsy specimen was 6.8% which provided 86% sensitivity and 81% specificity. We also obtained a good correlation between the MI and histological grade (WHO grading). Our new system also enabled finishing the process from sample preparation to the end of analysis in ten minutes or less. These results demonstrate that our fully automatic rapid DNA ploidy analyzer is feasible for rapid determination of glioma presence in a surgical biopsy sample.


Assuntos
DNA de Neoplasias/análise , Técnicas de Diagnóstico Molecular/instrumentação , Técnicas de Diagnóstico Molecular/métodos , Ploidias , Adulto , Automação , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Feminino , Citometria de Fluxo , Glioma/diagnóstico , Glioma/patologia , Glioma/cirurgia , Humanos , Período Intraoperatório , Masculino , Kit de Reagentes para Diagnóstico
2.
Artigo em Inglês | MEDLINE | ID: mdl-24110939

RESUMO

In aortic vascular surgery, a navigation system must represent the anatomical map of individual patient in order to detect the important artery. To provide a proper fit for positions along the dorsoventral axis, the spinous process was added to a currently used anatomical point set consisting of four anterior body landmarks. In addition, we attempted to reduce the registration error by compensating for alignment errors resulting from variations in tissue thickness at each landmark. The alignment values were examined using a human phantom consisting of a skeleton model with subcutaneous tissue in the semilateral position. Using this method, a phantom simulation and five clinical trials were performed. Target errors were evaluated at the orifice of the intercostal artery. In the phantom simulation, the error at the target point was 4.1 ± 2.7 mm. However, for one patient undergoing thoracoabdominal aortic aneurysm replacement surgery, the target error was 8.0 mm using the proposed method.


Assuntos
Aorta/cirurgia , Imagens de Fantasmas , Cirurgia Assistida por Computador/métodos , Procedimentos Cirúrgicos Vasculares/métodos , Aneurisma da Aorta Torácica/cirurgia , Desenho de Equipamento , Humanos , Cirurgia Assistida por Computador/instrumentação , Procedimentos Cirúrgicos Vasculares/instrumentação
3.
AJNR Am J Neuroradiol ; 34(1): 85-91, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22766670

RESUMO

BACKGROUND AND PURPOSE: Oligodendroglial tumors with 1p/19q LOH are known to show longer patient survival than those without 1p/19q LOH, but the reason for this clinical difference has not been elucidated, to our knowledge. This study was designed to clarify whether uptake of MET correlates with 1p/19q LOH of oligodendroglial tumors. MATERIALS AND METHODS: This study included 102 consecutive patients with supratentorial WHO grade II and III oligodendroglial tumors (39 oligoastrocytic and 63 oligodendroglial tumors) that were resected and diagnosed between January 2008 and August 2011 at Tokyo Women's Medical University Hospital. These patients underwent MET PET T/N ratio measurement before treatment. T/N ratios were calculated by dividing the maximum SUV for the tumor by the mean SUV of the contralateral normal frontal cortex. After surgery, FISH for resected tissues was used to determine 1p/19q LOH. RESULTS: The mean T/N ratio of tumors with 1p/19q LOH was significantly greater than that of tumors without 1p/19q LOH (P = .0166). The threshold T/N ratio value of 2.46 was found to correlate significantly with 1p/19q LOH by univariate (P = .0011) and multivariate analyses (P = .0209) in all tumors. CONCLUSIONS: The T/N ratio on MET PET might be a useful aid to the diagnosis of 1p/19q LOH. Our data add new information on the biology and imaging characteristics of oligodendroglial tumors with 1p/19q LOH.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Cromossomos Humanos Par 19/genética , Cromossomos Humanos Par 1/genética , Glioma/fisiopatologia , Metionina/análogos & derivados , Oligodendroglia/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Glioma/diagnóstico por imagem , Humanos , Perda de Heterozigosidade/genética , Masculino , Metionina/farmacocinética , Pessoa de Meia-Idade , Oligodendroglia/diagnóstico por imagem , Radiografia , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto , Adulto Jovem
4.
Br J Cancer ; 106(12): 1976-9, 2012 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-22588557

RESUMO

BACKGROUND: Translocated in liposarcoma-CCAAT/enhancer binding protein homologous protein (TLS-CHOP) (also known as FUS-DDIT3) chimeric oncoprotein is found in the majority of human myxoid liposarcoma (MLS), but its molecular function remains unclear. METHODS: We knockdowned TLS-CHOP expression in MLS-derived cell lines by a specific small interfering RNA, and analysed the gene expression profiles with microarray. RESULTS: TLS-CHOP knockdown inhibited growth of MLS cells, and induced an anticancer cytokine, melanoma differentiation-associated gene 7 (MDA-7)/interleukin-24 (IL-24) expression. However, double knockdown of TLS-CHOP and MDA-7/IL-24 did not inhibit MLS cell growth. CONCLUSION: Repression of MDA-7/IL-24 expression by TLS-CHOP is required for MLS tumour growth, and TLS-CHOP may become a promising therapeutic target for MLS treatment.


Assuntos
Interleucinas/metabolismo , Lipossarcoma Mixoide/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Proteína FUS de Ligação a RNA/metabolismo , Fator de Transcrição CHOP/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Interleucinas/genética , Lipossarcoma Mixoide/genética , Proteínas de Fusão Oncogênica/genética , Proteína FUS de Ligação a RNA/genética , Fator de Transcrição CHOP/genética
5.
Minim Invasive Neurosurg ; 54(5-6): 286-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22278800

RESUMO

BACKGROUND: Radiosurgical management of large cystic metastatic brain tumors represents a significant challenge. Nevertheless, modified dose planning has shown beneficial results in such cases. METHOD AND RESULTS: "Donut's shape" radiosurgical treatment planning is based on the chain-like application of multiple, small-sized isocenters for selective coverage of the contrast-enhancing tumor capsule and minimal irradiation of the central cystic area. Such an approach was used for the management of large cystic intracranial metastases, which were not accompanied by a significant mass effect and did not require immediate volume reduction. Treatment was done using Leksell Gamma Knife model C with automatic positioning system. The majority of treated lesions showed significant shrinkage after radiosurgery and no major complications were met. CONCLUSION: Large cystic metastatic brain tumors may be successfully treated with gamma knife radiosurgery alone using the proposed "donut's shape" dose planning with coverage of the contrast-enhancing tumor capsule by multiple small-sized isocenters.


Assuntos
Adenocarcinoma/secundário , Adenocarcinoma/cirurgia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Neoplasias Pulmonares/patologia , Procedimentos Neurocirúrgicos/métodos , Radiocirurgia/métodos , Idoso , Evolução Fatal , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/instrumentação , Radiocirurgia/instrumentação , Resultado do Tratamento
6.
Surg Endosc ; 23(9): 2138-42, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19116745

RESUMO

BACKGROUND: Ultrasonically activated devices (USADs) offer excellent coagulating dissection performance and are broadly used, particularly in endoscopic operations. Traditional USADs, however, have fixed linear shape and are thus limited in the directions from which organs can be approached. We have developed a small USAD transducer attached to the tip of an articulating device, offering a new kind of USAD in which the tip can bend as desired. We describe herein an evaluation of the coagulating dissection performance of this new articulating USAD and an in vivo confirmation of clinical usefulness. METHODS: To evaluate coagulating dissection performance, we compared coagulating shearing on porcine splenic arteries between the articulating USAD and a Harmonic Scalpel II (HSII), representing a traditional USAD. Changing the amplitude of vibration between 60 microm and 80 microm and grip force among 1, 2, and 3 N, we measured the time required for division and bursting pressure of coagulating dissection. An in vivo experiment in a pig was also used to confirm the usefulness of the articulating USAD in laparoscopic operations. RESULTS: Division time did not differ significantly between the articulating USAD and HSII with an 80-microm amplitude of vibration and a grip force of 2 or 3 N. Bursting pressure of blood vessels showed no significant difference between articulating USAD and HSII under all experimental conditions. In the in vivo experiment, the new bendable tip of the articulating USAD displayed coagulating dissection performance equivalent to that of the traditional USAD. CONCLUSIONS: We have developed a new articulating USAD that can broaden the range of methods and approaches available for USADs and improve usefulness and safety.


Assuntos
Dissecação/instrumentação , Hemostase Endoscópica/instrumentação , Ablação por Ultrassom Focalizado de Alta Intensidade/instrumentação , Laparoscopia/métodos , Robótica/instrumentação , Artéria Esplênica/cirurgia , Transdutores , Procedimentos Cirúrgicos Vasculares/instrumentação , Animais , Desenho de Equipamento , Sus scrofa , Procedimentos Cirúrgicos Vasculares/métodos , Vibração
7.
Minim Invasive Neurosurg ; 52(5-6): 216-21, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20077361

RESUMO

INTRODUCTION: The influence of histopathological grade and MIB-1 index of intracranial meningioma on the results of its radiosurgical management is not clear. The objective of the present retrospective study was to make an evaluation of these factors along with an analysis of other variables associated with progression-free survival after gamma knife radiosurgery (GKR). PATIENTS AND METHODS: Thirty-four intracranial meningiomas with known detailed histopathological diagnosis were analyzed. Tumors of WHO histopathological grades I, II, and III were diagnosed in 24, 3, and 7 cases, respectively. The median MIB-1 index was 1.3% (range: 0-31.9%). In 14 cases the MIB-1 index was 3.0% and more. In 26 cases the treatment was done at the time of tumor recurrence. Median volume of the neoplasm at the time of GKR was 4.1 mL (range: 0.4-43.1 mL). Median marginal dose was 12 Gy (range: 8-19 Gy). Median length of follow-up constituted 63 months (range: 19-132 months). RESULTS: Actuarial progression-free survival at 1, 3, 5, and 10 years constituted 100, 94, 83, and 58%, respectively. Histopathological grade II or III (p<0.0001), MIB-1 index 3% and more (p=0.0004), and non-skull base location (p=0.0026) of the tumor showed negative associations with progression-free survival in multivariate analyses. Actuarial progression-free survival at 5 years after GKR for benign and non-benign meningiomas constituted 100 and 45%, respectively (p<0.0001). CONCLUSION: Radiosurgery is a highly effective management option for benign intracranial meningiomas, but growth control of non-benign ones is significantly worse. It requires close neuroradiological follow-up and necessitates the search for modified treatment strategies.


Assuntos
Anticorpos Antinucleares/metabolismo , Anticorpos Monoclonais/metabolismo , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Radiocirurgia , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/imunologia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
8.
Stereotact Funct Neurosurg ; 87(1): 18-24, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19039259

RESUMO

BACKGROUND/AIMS: To identify the pyramidal tract by neuronavigation based on intraoperative diffusion-weighted imaging (iDWI) combined with subcortical stimulation. METHODS: Seven patients with brain tumors near the deep white matter underwent resection surgery using neuronavigation based on iDWI to visualize white matter bundles. Subcortical electrical stimulation was performed and electromyography was measured at the extremities when surgical manipulation came near the position corresponding to the depicted bundle. We validated the bundle depicted on iDWI by considering the responses to subcortical stimulation and the distance between the stimulation site and the depicted bundle. RESULTS: Positive motor-evoked potentials were detected in 5 of 7 patients (8 stimulations) and the distance from the stimulation site to the depicted bundle was 0-4.7 mm (mean +/- SD, 1.4 +/- 2.1 mm). Negative (no) responses were obtained in all patients when the distance was more than 5 mm. The neuronavigation system had an average error of 0.79 +/- 0.25 mm and a maximum error of 2.0 mm (n = 16). CONCLUSION: Neuronavigation based on iDWI combined with subcortical stimulation allowed surgeons to identify the pyramidal tract and avoid inadvertent injury. Our findings demonstrate that the white matter bundles depicted by iDWI can contain the pyramidal tract.


Assuntos
Neoplasias Encefálicas/fisiopatologia , Neoplasias Encefálicas/cirurgia , Imagem de Difusão por Ressonância Magnética/métodos , Potencial Evocado Motor/fisiologia , Período Intraoperatório/métodos , Neuronavegação/métodos , Tratos Piramidais/patologia , Adulto , Mapeamento Encefálico/métodos , Neoplasias Encefálicas/patologia , Córtex Cerebral/fisiopatologia , Estimulação Elétrica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Neuroradiol J ; 22(1): 58-71, 2009 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-24206954

RESUMO

The present study evaluated the dynamics of metabolic changes in intracranial metastases and distant normal-appearing brain after stereotactic radiosurgery (SRS). Forty neoplasms were evaluated with single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) both before and after treatment. From one to six examinations (median, 3) were done in each individual case during follow-up. At the time of each investigation additional (1)H-MRS was obtained from the normal-appearing brain distant from the radiosurgical target. Investigated metabolites included N-acetylaspartate (NAA), choline-containing compounds (Cho), creatine (Cr), and mobile lipids (Lip). Within the first month after SRS responded tumors showed a statistically significant increase in NAA/Cho ratio, and decrease of Cho content and Lip-to-normal brain Cr (nCr) ratio. By contrast, statistically significant metabolic alterations were not detected in stabilized tumors. Statistically significant volumetric and metabolic changes were not marked between three and 12 months after treatment in non-progressing lesions. Alternatively, decrease of NAA/Cho ratio, NAA content and Cr content, and increase in Lip/nCr ratio and Cho content were evident in progressive neoplasms, and subtle metabolic alterations could be revealed even before the increase in the lesion volume. Metabolic characteristics of normal-appearing brain distant from the radiosurgical target did not show statistically significant changes within the first year after treatment. In conclusion, additional use of serial (1)H-MRS during follow-up after SRS for intracranial metastases permits detailed evaluation of the metabolic tumor response and may be potentially helpful for early prediction of recurrence.

10.
Minim Invasive Neurosurg ; 51(5): 275-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18855292

RESUMO

The objective of the present study was an evaluation of the incidence and risk factors for erroneous histopathological diagnosis of low-grade glioma after stereotactic biopsy. Twenty-eight tumors diagnosed as low-grade glioma after stereotactic biopsy and surgically resected thereafter were analyzed. There were 13 astrocytomas, 7 oligodendrogliomas, and 8 mixed gliomas. All neoplasms had a lobar location. Seven tumors had contrast enhancement on MRI. The number of tissue samples obtained during stereotactic biopsy was one in 19 cases, two in 4, and three or more in 5. Complete diagnostic agreement in tumor typing and grading after stereotactic biopsy and surgical resection was attained in 10 cases (36%). Agreement in tumor typing was marked in 16 cases (57%). Erroneous typing was more frequent in tumors with an MIB-1 index of less than 3% (P = 0.0629) and mixed gliomas (P = 0.0801). Overgrading of WHO grade I tumors was marked in 3 cases (11%) and undergrading of WHO grade III gliomas in 8 cases (28%). Tumor undergrading was more frequent in cases with an MIB-1 index of more than 3% (P = 0.0045). The MIB-1 index detected after stereotactic biopsy was nearly always lower compared with those established after surgical resection (P < 0.0001). In conclusion, the histopathological diagnosis of low-grade glioma established after stereotactic biopsy is associated with a substantial risk of inaccuracy. Tumors with low proliferative activity and mixed gliomas are especially susceptible for erroneous tumor typing. Undergrading of high-grade gliomas may be suspected if the MIB-1 index in the tumor specimen constitutes more, than 3%.


Assuntos
Neoplasias Encefálicas/patologia , Erros de Diagnóstico/estatística & dados numéricos , Glioma/patologia , Adolescente , Adulto , Idoso , Astrocitoma/patologia , Biópsia/estatística & dados numéricos , Encéfalo/patologia , Encéfalo/cirurgia , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Índice Mitótico , Procedimentos Neurocirúrgicos , Variações Dependentes do Observador , Oligodendroglioma/patologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Técnicas Estereotáxicas/estatística & dados numéricos , Adulto Jovem
11.
Minim Invasive Neurosurg ; 51(5): 285-91, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18855294

RESUMO

The availability of the intraoperative MRI and real-time neuronavigation has dramatically changed the principles of surgery for gliomas. Current intraoperative computer-aided technologies permit perfect localization of the neoplasm, precise estimation of its volume, and clear definition of its interrelationships with the eloquent brain structures. This allows maximal tumor resection with minimal risk of postoperative disabilities. Under such conditions the medical treatment has become significantly dependent on the quality of the provided information and can be designated as information-guided management. Therefore, appropriate management of the wide spectrum of the intraoperative medical data and its adequate distribution between members of the surgical team for facilitation of the clinical decision-making is very important for attainment of the best possible outcome. Further progress in advanced neurovisualization, robotics, and comprehensive medical information technology has a great potential to increase the safety of the neurosurgical procedures for parenchymal brain tumors in the eloquent brain areas.


Assuntos
Neoplasias Encefálicas/cirurgia , Biologia Computacional/métodos , Glioma/cirurgia , Monitorização Intraoperatória/métodos , Neuronavegação/métodos , Cirurgia Assistida por Computador/métodos , Centros Médicos Acadêmicos/tendências , Biologia Computacional/tendências , Tomada de Decisões Assistida por Computador , Feminino , Humanos , Complicações Intraoperatórias/prevenção & controle , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/tendências , Monitorização Intraoperatória/instrumentação , Monitorização Intraoperatória/tendências , Neuronavegação/instrumentação , Neuronavegação/tendências , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Procedimentos Neurocirúrgicos/tendências , Robótica/instrumentação , Robótica/métodos , Robótica/tendências , Segurança/normas , Técnicas Estereotáxicas/instrumentação , Técnicas Estereotáxicas/tendências , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/tendências , Tóquio
12.
AJNR Am J Neuroradiol ; 29(10): 1867-71, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18687745

RESUMO

BACKGROUND AND PURPOSE: The relationship of (11)C-methionine (MET) uptake and tumor activity in low-grade gliomas (those meeting the criteria for World Health Organization [WHO] grade II gliomas) remains uncertain. The aim of this study was to compare MET uptake in low-grade gliomas and to analyze whether MET positron-emission tomography (PET) can estimate tumor viability and provide evidence of malignant transformation. MATERIALS AND METHODS: We studied glioma metabolic activity in 49 consecutive patients with newly diagnosed grade II gliomas by using MET PET before surgical resection. On MET PET, we measured tumor/normal brain uptake ratio (T/N ratio) in 21 diffuse astrocytomas (DAs), 12 oligodendrogliomas (ODs), and 16 oligoastrocytomas (OAs). We compared MET T/N ratio among these 3 tumors and investigated possible correlation with proliferative activity, as measured by Mib-1 labeling index (LI). RESULTS: MET T/N ratios of DA, OD, and OA were 2.11 +/- 0.87, 3.75 +/- 1.43, and 2.76 +/- 1.27, respectively. The MET T/N ratio of OD was significantly higher than that of DA (P < .005). In comparison of MET T/N ratios with the Mib-1 LI, a significant correlation was shown in DA (r = 0.63; P < .005) but not in OD and OA. CONCLUSION: MET uptake in DAs may be closely associated with tumor viability, which depends on increased amino acid transport by an activated carrier-mediated system. DAs with lower MET uptake were considered more quiescent lesions, whereas DA with higher MET uptake may act more aggressively.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/metabolismo , Glioma/diagnóstico por imagem , Glioma/metabolismo , Metionina/farmacocinética , Adulto , Radioisótopos de Carbono/farmacocinética , Feminino , Humanos , Masculino , Invasividade Neoplásica , Cintilografia , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
13.
Minim Invasive Neurosurg ; 51(3): 140-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18521784

RESUMO

Optimal management of cavernous sinus hemangiomas remains unclear. Total microsurgical removal of these neoplasms may be extremely difficult due to their rich vascularization. Three cases of cavernous sinus hemangioma treated with low-dose Gamma Knife radiosurgery are presented. Marginal dose varied from 10 to 13 Gy. Treatment planning and radiation dosimetry were done with a goal of conformal and selective coverage of the lesion with 50% prescription isodose line using multiisocenter technique. In all cases significant shrinkage of the neoplasm was marked at 3 months after treatment. Mean volume reduction at 12 months after radiosurgery was 60% (range: 45-75%). In all patients the shrinkage of the neoplasm was accompanied by notable improvement of the preexistent oculomotor nerve palsy. No radiosurgery-related complications were met during follow-up. In conclusion, low-dose Gamma Knife radiosurgery seems to be very effective for management of cavernous sinus hemangiomas, and can be considered as a treatment modality of choice for these lesions.


Assuntos
Neoplasias Encefálicas/cirurgia , Seio Cavernoso/cirurgia , Hemangioma Cavernoso do Sistema Nervoso Central/cirurgia , Neuronavegação , Radiocirurgia , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , Seio Cavernoso/patologia , Diagnóstico Diferencial , Feminino , Seguimentos , Hemangioma Cavernoso do Sistema Nervoso Central/diagnóstico , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Imagem por Ressonância Magnética Intervencionista , Masculino , Microcirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/cirurgia , Reoperação , Tomografia Computadorizada por Raios X
14.
Minim Invasive Neurosurg ; 51(2): 63-6, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18401815

RESUMO

Integration of intraoperative diffusion-weighted imaging (iDWI) into neuronavigation can be potentially useful for identification of the pyramidal tract during surgery for parenchymal brain lesions. The technique of iDWI using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. For image acquisition, a specially designed solenoid radiofrequency receiver coil integrated with a modified Sugita head holder (head-holder coil) was used. While the sensitivity characteristics of the head-holder coil were found to be 29% lower compared to a diagnostic quadrature head coil, they were sufficient to obtain iDWI images of good quality. The relationship between the angle of the motion probe gradient (MPG) pulse to the vertical axis and pyramidal tract contrasting were examined in 4 healthy men with a mean age of 30+/-5.7 years. The contrast ratio reached a maximum when the MPG pulse was applied exactly in the anteroposterior direction. The difference of the contrast ratio between right and left sides was not statistically significant. Pyramidal tract visualization became worse and the contrast ratio was reduced when the MPG pulse was applied at different angles to the vertical axis; the reduction rate varied from 20.1 to 27.9% for each 15 degrees of rotation irrespective of its side. In conclusion, the developed scanning protocol for iDWI using an originally designed head-holder coil allowed effective visualization of the pyramidal tracts using an intraoperative MR scanner of low magnetic field strength.


Assuntos
Encéfalo/anatomia & histologia , Imagem de Difusão por Ressonância Magnética/métodos , Monitorização Intraoperatória/métodos , Neuronavegação/métodos , Tratos Piramidais/anatomia & histologia , Adulto , Biomarcadores , Campos Eletromagnéticos , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Magnetismo , Masculino , Neuroanatomia/métodos , Procedimentos Neurocirúrgicos/métodos , Reprodutibilidade dos Testes
15.
Minim Invasive Neurosurg ; 51(2): 67-71, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18401816

RESUMO

Precise identification and preservation of the pyramidal tract during surgery for parenchymal brain tumors is of crucial importance for the avoidance of postoperative deterioration of the motor function. The technique of intraoperative diffusion-weighted imaging (iDWI) using an intraoperative MR scanner of low magnetic field strength (0.3 Tesla) has been developed. Its clinical usefulness and efficacy were evaluated in 10 surgically treated patients with gliomas (5 men and 5 women, mean age: 41.2+/-13.9 years). iDWI permitted visualization of the pyramidal tract on the non-affected side in all 10 cases, and on the affected side in 8 cases. Motion artifacts were observed in four patients, but were not an obstacle to identification of the pyramidal tract. Good correspondence of the anatomical landmarks localization on iDWI and T (1)-weighted imaging was found. All participating neurosurgeons agreed that, in the majority of cases, iDWI was very useful for localization of the pyramidal tract and for clarification of its spatial relationships with the tumor. In conclusion, image quality and accuracy of the iDWI obtained with an MR scanner of low magnetic field strength (0.3 Tesla) are sufficient for possible incorporation into an intraoperative neuronavigation system. The use of iDWI in addition to structural iMRl and subcortical functional mapping with electrical stimulation can potentially result in a reduction of the postoperative morbidity after aggressive surgical removal of lesions located in the vicinity to the motor white matter tracts.


Assuntos
Neoplasias Encefálicas/diagnóstico , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Glioma/diagnóstico , Monitorização Intraoperatória/métodos , Neuronavegação/métodos , Tratos Piramidais/anatomia & histologia , Adulto , Idoso , Biomarcadores , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Campos Eletromagnéticos , Feminino , Glioma/patologia , Glioma/cirurgia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Complicações Intraoperatórias/prevenção & controle , Magnetismo , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/métodos , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
16.
AJNR Am J Neuroradiol ; 29(6): 1176-82, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18388218

RESUMO

BACKGROUND AND PURPOSE: Positron-emission tomography (PET) is a useful tool in oncology. The aim of this study was to assess the metabolic activity of gliomas using (11)C-methionine (MET), [(18)F] fluorodeoxyglucose (FDG), and (11)C-choline (CHO) PET and to explore the correlation between the metabolic activity and histopathologic features. MATERIALS AND METHODS: PET examinations were performed for 95 primary gliomas (37 grade II, 37 grade III, and 21 grade IV). We measured the tumor/normal brain uptake ratio (T/N ratio) on each PET and investigated the correlations among the tracer uptake, tumor grade, tumor type, and tumor proliferation activity. In addition, we compared the ease of visual evaluation for tumor detection. RESULTS: All 3 of the tracers showed positive correlations with astrocytic tumor (AT) grades (II/IV and III/IV). The MET T/N ratio of oligodendroglial tumors (OTs) was significantly higher than that of ATs of the same grade. The CHO T/N ratio showed a significant positive correlation with histopathologic grade in OTs. Tumor grade and type influenced MET uptake only. MET T/N ratios of more than 2.0 were seen in 87% of all of the gliomas. All of the tracers showed significantly positive correlations with Mib-1 labeling index in ATs but not in OTs and oligoastrocytic tumors. CONCLUSION: MET PET appears to be useful in evaluating grade, type, and proliferative activity of ATs. CHO PET may be useful in evaluating the potential malignancy of OTs. In terms of visual evaluation of tumor localization, MET PET is superior to FDG and CHO PET in all of the gliomas, due to its straightforward detection of "hot lesions".


Assuntos
Neoplasias Encefálicas/metabolismo , Colina/farmacocinética , Fluordesoxiglucose F18/farmacocinética , Glioma/metabolismo , Metionina/farmacocinética , Tomografia por Emissão de Pósitrons/métodos , Adulto , Neoplasias Encefálicas/diagnóstico por imagem , Radioisótopos de Carbono/farmacocinética , Feminino , Perfilação da Expressão Gênica/métodos , Glioma/diagnóstico por imagem , Humanos , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacocinética , Distribuição Tecidual
17.
Neuroradiol J ; 21(3): 338-49, 2008 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-24256903

RESUMO

The usefulness of proton magnetic resonance spectroscopy ((1)H-MRS) for glioma grading is not clear, particularly due to the absence of standard criteria for data analysis. Previously we had developed an original classification of the pathological (1)H-MRS spectra based on the identification of the predominant metabolite peak, N-acetylaspartate (NAA) for Type I, choline-containing compounds (Cho) for Type II, and mobile lipids (Lip) for Type III, and presence or absence of other metabolite peaks: lactate (Lac), Lip, or Cho. The present study evaluated the effectiveness of this classification in grading of previously non-treated gliomas. A total of 38 low-grade and 33 high-grade neoplasms were investigated. Four tumors had (1)H-MRS spectra Type I, and all of those were low-grade. Three tumors had (1)H-MRS spectra Type III, and all those were glioblastomas. Fifteen tumors with (1)H-MRS spectra Type II had a Lip/NAA ratio more than 1 (Type II C with moderate elevation of lipids), and 12 of those neoplasms were high-grade. The differences in distribution of high-grade and low-grade gliomas among another 49 gliomas with (1)H-MRS spectra Type II did not depend on the presence of Lac and/or Lip peaks, and in this subgroup NAA/Cho ratio was also evaluated. Inclusion of both characteristics (type of the (1)H-MRS spectrum and NAA/Cho ratio with defined cut-off level of 0.6) into the diagnostic algorithm yielded 72% diagnostic accuracy (95% confidence interval: 62%-82%) in discriminating high-grade and low-grade neoplasms. In conclusion, pattern analysis of the pathological (1)H-MRS spectra using the proposed classification along with evaluation of NAA/Cho ratio might be helpful for non-invasive glioma grading.

18.
Minim Invasive Neurosurg ; 50(4): 233-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17948183

RESUMO

Metabolic characteristics of intracranial metastases, detected with proton magnetic resonance spectroscopy (1H-MRS) have known associations with clinical predictors of tumor response to radiosurgery. Therefore, it can be suspected that the metabolic profile of the neoplasm by itself might have some prognostic significance for the outcome after irradiation. Twenty-six intracranial metastases, which underwent metabolic evaluation with single-voxel 1H-MRS before gamma knife radiosurgery (GKR) and were followed for at least 3 months after treatment, were selected for retrospective analysis. The tumors most frequently originated from the lungs (9 cases), breast (7 cases), colon and rectum (5 cases). The average volume of the investigated intracranial neoplasm was 5.4+/-2.0 mL. The average marginal irradiation dose was 18.6+/-2.3 Gy. The mean follow-up after GKR constituted 8.0+/-5.5 months. Tumor response to GKR was identified in 13 cases on average 2.2+/-1.8 months after treatment. Local recurrence was marked in 10 cases on average 8.7+/-4.1 months after treatment. None of the investigated 1H-MRS metabolic parameters of intracranial metastases showed a statistically significant association with the outcome after GKR. The negative results of the present study make doubtful the predictive value of metabolic characteristics of intracranial metastases, detected with single-voxel 1H-MRS, for the outcome after radiosurgery.


Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma/secundário , Carcinoma/cirurgia , Metabolismo Energético/fisiologia , Espectroscopia de Ressonância Magnética/métodos , Radiocirurgia/métodos , Idoso , Neoplasias Encefálicas/diagnóstico , Carcinoma/diagnóstico , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico , Metástase Neoplásica/fisiopatologia , Metástase Neoplásica/terapia , Valor Preditivo dos Testes , Prognóstico , Prótons , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento
19.
Acta Neurochir Suppl ; 98: 67-75, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17009703

RESUMO

BACKGROUND: Radical resection of gliomas can increase patient's survival. There is known concern, however, that aggressive tumour removal can result in neurological morbidity. The objective of the present study was to evaluate the usefulness of low magnetic field strength (0.3 Tesla) open intraoperative magnetic resonance imaging (iMRI) for complete resection of glioma with emphasis on functional outcome. METHODS: From 2000 to 2004, 96 patients with intracranial gliomas underwent tumour resection with the use of iMRI in Tokyo Women's Medical University. There were 50 men and 46 women; mean age was 39 years. Tumour volume varied from 1.2 ml to 198 ml (median: 36.5 mL). Resection rate and postoperative neurological status were compared between control group (46 cases, operated on during the initial period after installation of iMRI), and study group (50 most recent cases, in whom surgery was done using established treatment algorithm and improved image quality). FINDINGS: Overall, mean resection rate was 93%, and medial residual tumour volume was 0.17 ml. Total tumour removal was achieved in 44 cases (46%). Compared to control group, resection rate in the study group was significantly higher (91%, vs. 95%; P < 0.05), whereas residual tumour volume was significantly smaller (1.7 mL vs. 0.025 mL; P < 0.001). Nine patients in the control group (20%) and 24 in the study group (48%) experienced temporary postoperative neurological deterioration (P < 0.01), however, the rate of permanent morbidity evaluated 3 months after surgery did not differ significantly between the groups investigated (13% vs. 14%). CONCLUSIONS: Use of iMRI during surgery for intracranial gliomas permits to attain aggressive tumour resection with good functional outcome. Nevertheless, surgical experience with the iMRI system, establishment of treatment algorithm, and improvement of image quality are of paramount importance for optimal results.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Imageamento por Ressonância Magnética/métodos , Neuronavegação , Cirurgia Assistida por Computador , Adulto , Neoplasias Encefálicas/patologia , Feminino , Seguimentos , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
20.
Kidney Int ; 70(3): 486-95, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16788697

RESUMO

Direct maxacalcitol (OCT) injection into a parathyroid gland (PTG) ameliorates several important etiologic factors of resistance to medical treatments for secondary hyperparathyroidism (s-HPT): the upregulations of vitamin D receptor (VDR) and Ca-sensing receptor (CaSR) in PTGs and the regression of PTG hyperplasia by the induction of apoptosis. In this study, we evaluated the bone histomorphology on the basis of maintaining these effects in advanced s-HPT. Five/six nephrectomized Sprague-Dawley rats were fed a high-phosphorus and low-calcium diet for 8 weeks. These rats were divided into four treatment groups: (1) basic uremic (at the baseline), (2) direct OCT single injection into PTGs (DI-OCT) followed by OCT intravenous administration for 4 weeks (IV-OCT), (3) direct vehicle injection and IV-OCT, and (4) no treatment for an additional 4 weeks. The effects of these treatments on serum intact-parathyroid hormone (PTH) level, PTG weight, VDR and CaSR expression levels in PTGs, and bone histomorphometric parameters were investigated. In the DI-OCT+IV-OCT group, the significant decrease in serum intact-PTH level was maintained by the following IV-OCT. A significant decrease in PTG weight and the upregulations of VDR and CaSR expression levels in PTGs were also observed. Bone histomorphometric analysis showed significant improvements in osteitis fibrosa in both cancellous and cortical bones. However, these findings were not observed in the other groups. These results suggest that osteitis fibrosa caused by advanced s-HPT can be successfully reversed by a control of PTH at an appropriate level through the improvement of PTG hyperplasia as induced by DI-OCT+IV-OCT.


Assuntos
Antineoplásicos/farmacologia , Calcitriol/análogos & derivados , Distúrbio Mineral e Ósseo na Doença Renal Crônica/tratamento farmacológico , Hiperparatireoidismo Secundário/tratamento farmacológico , Animais , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Calcitriol/farmacologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/etiologia , Distúrbio Mineral e Ósseo na Doença Renal Crônica/patologia , Hiperparatireoidismo Secundário/complicações , Hiperparatireoidismo Secundário/patologia , Hiperplasia , Imuno-Histoquímica , Injeções Intralesionais , Falência Renal Crônica/complicações , Masculino , Tamanho do Órgão , Glândulas Paratireoides/patologia , Hormônio Paratireóideo/genética , Periósteo/metabolismo , Periósteo/patologia , Antígeno Nuclear de Célula em Proliferação/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Receptores de Detecção de Cálcio/genética , Receptores de Detecção de Cálcio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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