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1.
AJNR Am J Neuroradiol ; 34(5): 1028-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23179653

RESUMO

BACKGROUND AND PURPOSE: Seizures are a common presentation in patients with brain arteriovenous malformations, but the pathogenesis of seizures remains poorly understood. The purpose of our study was to analyze various morphologic and hemodynamic characteristics of unruptured BAVMs presenting primarily with seizures and, on the basis of these, to propose a scoring system to predict seizures in patients with BAVMs. MATERIALS AND METHODS: In a retrospective review of our BAVM data base from 2000 to 2009, after excluding patients with ruptured BAVMs, we classified patients into 2 groups, those with and without seizures at presentation. Clinical, angiographic, and hemodynamic characteristics on cerebral angiograms of all these patients were studied. The association between various angioarchitectural variables and seizure presentation was examined, and these results were used to guide the development of criteria to predict presentation with seizures. RESULTS: Of 1299 patients in our data base, we finally analyzed 33 patients with unruptured BAVMs with seizures and 45 patients with unruptured AVMs without seizures. Location, fistulous component in the nidus, venous outflow stenosis, and the presence of a long pial course of the draining vein were identified as the strongest predictors of seizures. The proposed scoring system had good predictability of presentation with seizures. CONCLUSIONS: Specific angioarchitectural characteristics of unruptured BAVMs may predict occurrence of seizures and may help in targeted treatment.


Assuntos
Algoritmos , Angiografia Cerebral/métodos , Malformações Arteriovenosas Intracranianas/diagnóstico , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Convulsões/diagnóstico , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Criança , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/complicações , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Convulsões/etiologia , Sensibilidade e Especificidade , Adulto Jovem
2.
Ultrasound Obstet Gynecol ; 38(6): 630-4, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21404357

RESUMO

OBJECTIVES: To evaluate diagnostic performance of intracranial translucency (IT) for detection of open spina bifida and interobserver agreement for visualization of IT during the 11-13-week scan. METHODS: A retrospective study was undertaken in a tertiary referral center. Two hundred 11-13-week scans for nuchal translucency, performed by sonographers certified by The Fetal Medicine Foundation, U.K., were reviewed independently for IT by two expert observers. When IT was not seen, the observers determined whether this was due to poor IT image quality or the presence of spina bifida. Discordant cases were reviewed by a third observer and the majority decision was used for analysis. All observers were blinded to individual pregnancy outcome and the number of cases with spina bifida. RESULTS: There were 191 normal fetuses, eight fetuses with open spina bifida and one with closed spina bifida (this case was excluded from analysis). IT was seen in 150 fetuses and all were normal. In six of the 49 cases in which IT was not seen, IT non-visibility was attributed to open spina bifida; among these cases, four fetuses had open spina bifida and two were normal. In the remaining 43 cases (including 39 normal fetuses), IT non-visibility was attributed to inadequate image quality. Sensitivity was 50% (4/8) and specificity was 99% (150/152). Concordance between the two observers concerning IT visibility was 79%, (κ = 0.47, representing moderate agreement). CONCLUSION: There was moderate interobserver agreement for visualization of IT on images obtained for nuchal translucency measurement at 11-13 weeks. When IT was confidently seen, open spina bifida could be excluded. However, non-visibility of IT correctly diagnosed only 50% of fetuses with open spina bifida.


Assuntos
Quarto Ventrículo/diagnóstico por imagem , Medição da Translucência Nucal/métodos , Espinha Bífida Cística/diagnóstico por imagem , Adulto , Estatura Cabeça-Cóccix , Feminino , Quarto Ventrículo/anormalidades , Quarto Ventrículo/embriologia , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Gravidez , Primeiro Trimestre da Gravidez , Estudos Retrospectivos , Espinha Bífida Cística/embriologia , Adulto Jovem
3.
Phys Med Biol ; 55(5): 1363-80, 2010 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-20145292

RESUMO

Increased pixel noise and streak artifact reduce CT image quality and limit the potential for radiation dose reduction during CT of the thoracic inlet. We propose to quantify the pixel noise of mediastinal structures in the thoracic inlet, during low-dose (LDCT) and ultralow-dose (uLDCT) thoracic CT, and assess the utility of new software (quantum denoising system and BOOST3D) in addressing these limitations. Twelve patients had LDCT (120 kV, 25 mAs) and uLDCT (120 kV, 10 mAs) images reconstructed initially using standard mediastinal and lung filters followed by the quantum denoising system (QDS) to reduce pixel noise and BOOST3D (B3D) software to correct photon starvation noise as follows: group 1 no QDS, no B3D; group 2 B3D alone; group 3 QDS alone and group 4 both QDS and B3D. Nine regions of interest (ROIs) were replicated on mediastinal anatomy in the thoracic inlet, for each patient resulting in 3456 data points to calculate pixel noise and attenuation. QDS reduced pixel noise by 18.4% (lung images) and 15.8% (mediastinal images) at 25 mAs. B3D reduced pixel noise by approximately 8% in the posterior thorax and in combination there was a 35.5% reduction in effective radiation dose (E) for LDCT (1.63-1.05 mSv) in lung images and 32.2% (1.55-1.05 mSv) in mediastinal images. The same combination produced 20.7% reduction (0.53-0.42 mSv) in E for uLDCT, for lung images and 17.3% (0.51-0.42) for mediastinal images. This quantitative analysis of image quality confirms the utility of dedicated processing software in targeting image noise and streak artifact in thoracic LDCT and uLDCT images taken in the thoracic inlet. This processing software potentiates substantial reductions in radiation dose during thoracic LDCT and uLDCT.


Assuntos
Artefatos , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos , Radiografia Torácica/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Reprodutibilidade dos Testes , Software
4.
Oncology ; 73(5-6): 305-10, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18493157

RESUMO

PURPOSE: It was the aim of this study to assess the risk of lung cancer in postmenopausal women who received hormone replacement therapy (HRT). EXPERIMENTAL DESIGN: This case-control study involves women who received medical services at Roswell Park Cancer Institute (RPCI) in Buffalo, New York, between 1982 and 1998, and who agreed to complete an epidemiological questionnaire. Participants with missing smoking data were excluded. The case group consisted of 595 women with primary lung cancer. Controls included 1,195 women, randomly selected from a pool of 5,845 eligible individuals, who received medical services at RPCI for non-neoplastic conditions; they had come to RPCI with a suspicion of neoplastic disease, but were diagnosed with neither benign nor malignant conditions. Controls were frequency matched 2:1 to cases on 5-year age intervals and exposure to smoking (ever/never). Cases and controls were comparable for age (means 61.3 and 61.0 years) and ever smoking (90%). RESULTS: There were more former smokers among the cases (67 vs. 59% in controls); cases were less likely to be high school educated, were thinner, and were less likely to report HRT use compared with controls. Overall, hormone use was associated with a significant reduction in risk of lung cancer (adjusted odds ratio = 0.67; 95% confidence interval 0.53-0.85). Stratified analyses showed significant reductions in lung cancer risk in former smokers and women with normal to low body mass index. CONCLUSION: This study supports the hypotheses that there is a protective effect of HRT use on lung cancer risk in women.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Terapia de Reposição de Estrogênios/efeitos adversos , Neoplasias Pulmonares/induzido quimicamente , Adulto , Idoso , Idoso de 80 Anos ou mais , Peso Corporal , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Obesidade/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Fumar/efeitos adversos , Inquéritos e Questionários
5.
Int J Gynecol Cancer ; 16 Suppl 1: 211-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16515593

RESUMO

It is unclear whether smoking is a risk factor for epithelial ovarian cancer, although some studies have suggested that it may be associated with an increased risk of mucinous tumors. This study investigated the effect of smoking and environmental tobacco smoke (ETS) on ovarian cancer risk among 434 women with primary epithelial ovarian, peritoneal, or fallopian cancers and 868 age- and region-matched hospital controls with nonneoplastic conditions. All participants completed a comprehensive epidemiologic questionnaire. Results indicate that decreased risk of ovarian cancer was associated with being a nonsmoker exposed to ETS (adjusted odds ratio [aOR] 0.68, 95% confidence interval [CI] 0.46-0.99), a former smoker (aOR 0.76, 95% CI 0.53-1.10), or a current smoker (aOR 0.53, 95% CI 0.32-0.88). A similar protective effect was noted for smokers with moderate or high exposure based on smoking intensity, duration, and cumulative exposure, as well as for never smokers exposed to ETS. Results did not differ substantially by histologic subtype. Although prevailing theories of ovarian cancer etiology implicate incessant ovulation, characteristics of the study population suggest that anovulation was not the protective mechanism in this study. Immunosuppression by nicotine or upregulation of enzymes that metabolize carcinogens may be responsible for the effects observed.


Assuntos
Neoplasias Epiteliais e Glandulares/etiologia , Neoplasias Ovarianas/etiologia , Fumar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Fatores de Risco
6.
Cancer Epidemiol Biomarkers Prev ; 10(8): 903-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11489759

RESUMO

Analgesics have been shown to reduce risk for colorectal cancer. Results from three recent reports (D. W. Cramer et al., Lancet, 351: 104-107, 1998; C. Rodriguez et. al., Lancet, 352: 1354-1355, 1998; L. Rosenberg et al., Cancer Epidemiol. Biomark. Prev., 9: 933-937, 2000) suggest that these drugs might be associated with decreased risk for ovarian cancer. In this hospital-based case-control study, we compared 547 patients with ovarian cancer to 1094 age-matched patients with nonneoplastic conditions. All of the participants received treatment at the Roswell Park Cancer Institute between 1982 and 1998 and completed a comprehensive epidemiological questionnaire that included information on demographics, life-style factors, and reproductive characteristics as well as frequency and duration of aspirin and acetaminophen use. Women who reported that they had used one or more of these agents at least once a week for at least 6 months were classified as analgesic users. Logistic regression was used to compute crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Aspirin users were not at reduced risk of ovarian cancer compared with nonusers (adjusted OR, 1.00; CI, 0.73-1.39). There was also no evidence of a decrease in risk as a function of greater frequency of use or prolonged duration of use. Regular acetaminophen use was associated with a reduced risk (adjusted OR, 0.56; 95% CI, 0.34-0.86), and risk reductions were observed for women with the greatest frequency of use (adjusted OR, 0.32; 95% CI, 0.09-1.08) and longest duration of use (adjusted OR, 0.51; 95% CI, 0.27-0.97). These data suggest that regular use of acetaminophen, but not aspirin, may be associated with lower risk of ovarian cancer.


Assuntos
Acetaminofen/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Neoplasias Ovarianas/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Fatores de Risco
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