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1.
Phys Med Biol ; 52(5): 1387-407, 2007 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-17301461

RESUMO

The performance of an automatic software package was evaluated with phantom images acquired by a full-field digital mammography unit. After the validation, the software was used, together with a Leeds TORMAS test object, to model the image acquisition process. Process modelling results were used to evaluate the sensitivity of the method in detecting changes of exposure parameters from routine image quality measurements in digital mammography, which is the ultimate purpose of long-term reproducibility tests. Image quality indices measured by the software included the mean pixel value and standard deviation of circular details and surrounding background, contrast-to-noise ratio and relative contrast; detail counts were also collected. The validation procedure demonstrated that the software localizes the phantom details correctly and the difference between automatic and manual measurements was within few grey levels. Quantitative analysis showed sufficient sensitivity to relate fluctuations in exposure parameters (kV(p) or mAs) to variations in image quality indices. In comparison, detail counts were found less sensitive in detecting image quality changes, even when limitations due to observer subjectivity were overcome by automatic analysis. In conclusion, long-term reproducibility tests provided by the Leeds TORMAS phantom with quantitative analysis of multiple IQ indices have been demonstrated to be effective in predicting causes of deviation from standard operating conditions and can be used to monitor stability in full-field digital mammography.


Assuntos
Inteligência Artificial , Mamografia/instrumentação , Mamografia/métodos , Garantia da Qualidade dos Cuidados de Saúde/métodos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Imagens de Fantasmas , Intensificação de Imagem Radiográfica/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Phys Med Biol ; 51(17): 4233-51, 2006 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16912379

RESUMO

Early manifestation of breast cancer is often very subtle and is displayed in a complex and variable pattern of normal anatomy that may obscure the disease. The use of dual-energy techniques, that can remove the structural noise, and contrast media, that enhance the region surrounding the tumour, could help us to improve the detectability of the lesions. The aim of this work is to investigate the use of an iodine-based contrast medium in mammography with two different double exposure techniques: K-edge subtraction mammography and temporal subtraction mammography. Both techniques have been investigated by using an ideal source, like monochromatic beams produced at a synchrotron radiation facility and a clinical digital mammography system. A dedicated three-component phantom containing cavities filled with different iodine concentrations has been developed and used for measurements. For each technique, information about the minimum iodine concentration, which provides a significant enhancement of the detectability of the pathology by minimizing the risk due to high dose and high concentration of contrast medium, has been obtained. In particular, for cavities of 5 and 8 mm in diameter filled with iodine solutions, the minimum concentration needed to obtain a contrast-to-noise ratio of 5 with a mean glandular dose of 2 mGy has been calculated. The minimum concentrations estimated with monochromatic beams and K-edge subtraction mammography are 0.9 mg ml(-1) and 1.34 mg ml(-1) for the biggest and smallest details, respectively, while for temporal subtraction mammography they are 0.84 mg ml(-1) and 1.31 mg ml(-1). With the conventional clinical system the minimum concentrations for the K-edge subtraction mammography are 4.13 mg ml(-1) (8 mm diameter) and 5.75 mg ml(-1) (5 mm diameter), while for the temporal subtraction mammography they are 1.01 mg ml(-1) (8 mm diameter) and 1.57 mg ml(-1) (5 mm diameter).


Assuntos
Algoritmos , Meios de Contraste/química , Iodo/química , Técnica de Subtração , Relação Dose-Resposta a Droga , Humanos , Mamografia/instrumentação , Mamografia/métodos , Imagens de Fantasmas , Controle de Qualidade , Doses de Radiação , Intensificação de Imagem Radiográfica/métodos
3.
Am J Psychiatry ; 158(3): 489-92, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11229996

RESUMO

OBJECTIVE: The authors address whether a possible age-at-onset cohort effect may have introduced a bias into anticipation studies of schizophrenia. METHOD: A retrospective review of the medical records of all admissions for psychotic disorders (N=877) was conducted. All subjects with a confirmed DSM-IV diagnosis of schizophrenia and age-at-onset data were included (N=419). For analyses, subjects were placed into one of three successive birth cohorts: 1905-1944 (N=96), 1945-1964 (N=200), and 1965-1984 (N=123). RESULTS: The mean age at first appearance of psychotic symptoms and, similarly, the mean age at first hospitalization significantly decreased over time in successive birth cohorts (25.3, 23.3, and 20.4 years, respectively, for age at first appearance of psychotic symptoms). CONCLUSIONS: This potential birth cohort effect for age at onset of schizophrenia needs to be incorporated into genetic models.


Assuntos
Esquizofrenia/epidemiologia , Adulto , Fatores Etários , Idade de Início , Efeito de Coortes , Estudos de Coortes , Comorbidade , Família , Feminino , França/epidemiologia , Registros Hospitalares/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Modelos Genéticos , Prevalência , Estudos Retrospectivos , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
4.
Phys Med Biol ; 48(13): 1945-56, 2003 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-12884927

RESUMO

A dual-energy technique which employs the basis decomposition method is being investigated for application to digital mammography. A three-component phantom, made up of plexiglas, polyethylene, and water, was doubly exposed with the full-field digital mammography system manufactured by General Electric. The 'low' and 'high' energy images were recorded with a Mo/Mo anode-filter combination and a Rh/Rh combination, respectively. The total dose was kept within the acceptable levels of conventional mammography. The first hybrid images obtained with the dual-energy algorithm are presented in comparison with a conventional radiograph of the phantom. Image-quality characteristics at contrast cancellation angles between plexiglas and water are discussed. Preliminary results show that a combination of a standard Mo-anode 28 kV radiograph with a Rh-anode 49 kV radiograph provides the best compromise between image-quality and dose in the hybrid image.


Assuntos
Diagnóstico por Imagem/métodos , Mamografia/instrumentação , Mamografia/métodos , Algoritmos , Calibragem , Meios de Contraste/farmacologia , Modelos Estatísticos , Imagens de Fantasmas , Raios X
5.
J Exp Clin Cancer Res ; 21(3 Suppl): 115-24, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12585665

RESUMO

This report presents the preliminary results of the first phase (21 months) of a multi-centre, non-randomised, prospective study, aimed at evaluating the effectiveness of contrast-enhanced magnetic resonance imaging (MRI), X-ray mammography (XM) and ultrasound (US) in early diagnosis of breast cancer (BC) in subjects at high genetic risk. This Italian national trial (coordinated by the Istituto Superiore di Sanità, Rome) so far recruited 105 women (mean age 46.0 years; median age 51.0; age range 25-77 years), who were either proven BRCA1 or BRCA2 mutation carriers or had a 1 in 2 probability of being carriers (40/105 with a previous personal history of BC). Eight cases of breast carcinomas were detected in the trial (mean age 55.3 years, median age 52.5; age range 35-70 years; five with previous personal history of BC). All trial-detected BC cases (8/8) were identified by MRI, while XM and US correctly classified only one. MRI had one false positive case, XM and US none. Seven "MRI-only" detected cancers (4 invasive, 3 in situ) occurred in both pre- (n = 2) and post-menopausal (n = 5) women. With respect to the current XM screening programmes addressed to women in the age range 50-69 years, the global incidence of BC in the trial (7.6%) was over ten-fold higher. The cost per "MRI-only" detected cancer in this particular category of subjects at high genetic risk was substantially lower than that of an XM-detected cancer in the general women population. These preliminary results confirmed that MRI is a very useful tool to screen subjects at high genetic risk for breast carcinoma, not only in pre-, but also in post-menopausal age, with a low probability of false positive cases.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética , Programas de Rastreamento , Adulto , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Reações Falso-Positivas , Feminino , Gadolínio , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Humanos , Mamografia , Programas de Rastreamento/economia , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Intensificação de Imagem Radiográfica , Ultrassonografia Mamária
6.
Tumori ; 73(5): 457-61, 1987 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-3686678

RESUMO

The authors report on a multicentric consecutive series of 382 cases of primary breast cancer detected before the age of 40 years. Physical examination (PE) was always performed, whereas other diagnostic tests were performed in selected cases, namely mammography (M) in 334, fine needle aspiration cytology (CYT) in 188 and thermography (TH) in 123 cases. Single tests showed a high rate of false-negative/benign cases (PE, 0.23; M, 0.26; CYT, 0.37 and TH, 0.50), especially when the T1 subgroup was considered (PE, 0.34; M, 0.38; CYT, 0.42 and TH, 0.78). The poor results recorded for TH make its current diagnostic use highly questionable. The policy of extensive biopsy of all "dubious" benign lesions on PE allowed for the detection of 41 of 382 cancers and reduced the PE false-negative/benign rate to 0.12 for the total or 0.15 for T1 cancers, although about 80 unnecessary biopsies for each cancer detected were performed in this way. The association of PE to one or more tests resulted in even lower false-negative rates (0.06 for the total, 0.10 for T1 cancers). The authors criticize the aggressive policy of extensive biopsy recommendation based only on a dubious report on PE alone and stress the opportunity of the routine association of M and CYT to PE, since this combination seems to achieve a higher breast cancer detection rate even in this age group.


Assuntos
Neoplasias da Mama/diagnóstico , Adulto , Fatores Etários , Biópsia por Agulha , Reações Falso-Negativas , Feminino , Humanos , Mamografia , Exame Físico , Estudos Retrospectivos , Termografia
7.
Minerva Med ; 74(39): 2309-11, 1983 Oct 13.
Artigo em Italiano | MEDLINE | ID: mdl-6657099

RESUMO

Tuberculosis of the breast is quite rare. Three cases, histologically proved, are reported; one of them was associated with a carcinoma. Clinical and radiological tools can hardly differentiate tubercular from tumoral nodules.


Assuntos
Doenças Mamárias/patologia , Tuberculose dos Genitais Femininos/patologia , Idoso , Doenças Mamárias/diagnóstico , Neoplasias da Mama/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Tuberculose dos Genitais Femininos/diagnóstico
8.
Minerva Med ; 68(24): 1655-62, 1977 May 12.
Artigo em Italiano | MEDLINE | ID: mdl-865706

RESUMO

Respiratory function investigations (spirometry, capillary haemogasanalysis and Xenon 133), before and after dialysis, have been carried out in 10 uraemic patients. Methods of investigation and the results showing a post-dialysis improvement of the lung ventilation and perfusion function, are described.


Assuntos
Diálise Renal , Testes de Função Respiratória/métodos , Uremia/fisiopatologia , Adolescente , Adulto , Humanos , Masculino , Fluxo Expiratório Máximo , Pessoa de Meia-Idade , Consumo de Oxigênio , Fatores de Tempo , Uremia/terapia , Relação Ventilação-Perfusão
9.
Chir Ital ; 28(6): 616-23, 1976 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-1029525

RESUMO

The appearance of a dehiscence after an operation of oesophageal resection and reconstruction with stomach, jejunum or colon, constitutes a highly serious event frequently leading to the patient's death. Early recognition of dehiscence is therefore important for the purpose of starting adequate therapy as quickly as possible and preventing the rise and establishment of those lesions which condition an irreversible trend of the clinical condition. In this note the means today available for early diagnosis fo fistula, with particular reference to early radiological examination, are discussed. Early diagnosis and adequate prompt treatment may, in our opinion, lead to an improvement in the poor results reported by a number of surgical schools.


Assuntos
Colo/cirurgia , Fístula Esofágica/diagnóstico , Esôfago/cirurgia , Gastrectomia , Deiscência da Ferida Operatória/diagnóstico , Neoplasias Esofágicas/cirurgia , Estenose Esofágica/cirurgia , Esofagite Péptica/complicações , Humanos , Complicações Pós-Operatórias
10.
Recenti Prog Med ; 80(9): 455-9, 1989 Sep.
Artigo em Italiano | MEDLINE | ID: mdl-2595075

RESUMO

It is well established that food ingestion induces increased thermogenesis, but the site in man of this increased heat production is still not known. Recent data suggest that brown adipose tissue or the liver may have an important role in this phenomenon. Since recent research provides some evidence to suggest that activation of thermogenesis in a specific organ or tissue may determine increased skin temperature in the surrounding region, we have studied skin temperature in the dorsal interscapular and in the liver regions using infra-red thermography in groups of normal and obese subjects before and after administration of oral glucose. In a separate group of normal subjects we studied oxygen consumption before and after glucose administration. While oral glucose produced a clear increase in thermogenesis, no ascertainable variation was observed in body temperature and, therefore, of heat dispersion in any of the regions studied in either normal or obese subjects.


Assuntos
Regulação da Temperatura Corporal , Glucose/fisiologia , Obesidade/fisiopatologia , Termografia , Adulto , Ingestão de Alimentos , Feminino , Humanos , Região Lombossacral , Masculino , Pessoa de Meia-Idade , Temperatura Cutânea
18.
Radiol Med ; 113(8): 1085-95, 2008 Dec.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-18953635

RESUMO

The clinical use of breast magnetic resonance (MR) imaging is increasing, especially for applications requiring paramagnetic contrast-agent injection. This document presents a synthetic list of acceptable indications with potential advantages for women according to evidence from the literature and the expert opinion of the panel that developed this statement. We generally recommend that breast MR imaging be performed in centres with experience in conventional breast imaging [mammography and ultrasonography (US)] and needle-biopsy procedures (under stereotactic or US guidance) as well as in breast MR imaging and second-look US for findings not revealed by conventional imaging performed before MR imaging. In our opinion, there is no evidence in favour of breast MR imaging as a diagnostic tool to characterise equivocal findings at conventional imaging when needle-biopsy procedures can be performed, nor for the study of asymptomatic, non-high-risk women with negative conventional imaging. After a description of technical and methodological requirements, we define the indications and limitations of breast MR imaging for surveillance of high-risk women, local staging before surgery, evaluation of the effect of neoadjuvant chemotherapy, breast previously treated for carcinoma, carcinoma of unknown primary syndrome, nipple discharge and breast implants.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética , Feminino , Humanos
19.
Radiol Med ; 98(4): 255-8, 1999 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-10615363

RESUMO

PURPOSE: We evaluated the results obtained by 130 Italian radiologists undergoing a proficiency test of clinical mammography. MATERIAL AND METHODS: Radiologists were invited to report a series of 100 mammograms (two views), including 32 cancers and 78 non-cancers, with limited information regarding age, subjective symptoms, and findings at palpation. Sensitivity and specificity were then calculated. The test was validated by a panel of experts, and standards for test sufficiency were established on that basis (sensitivity > 80%, specificity > 85%). The tested radiologists differed by mammographic practice (average = 5.7 years, range 0.5-18), total number of mammograms read (average = 8,784, range 300-50,000) and per year (average = 1,535 range 300-5,000). RESULTS: Sensitivity (standard > 80%, average 81.1%, range 39-100%) and specificity (standard > 85%, average 84.0%, range 38-98%) standards were reached by 79 (60.8%) and 81 (62.3%) radiologists, respectively. Overall, only 37 (28.5%) radiologists passed the test (reached both standards). Mammographic practice (years of experience) (chi 2 for trend 5.26, p = 0.02), total mammograms read (chi 2 5.86, p = 0.05), and mammograms read per year (chi 2 8.07, p = 0.01) significantly correlated with a sufficient test. DISCUSSION: The evaluated sample is rather large but not necessarily representative of Italian radiologists. Had the sample been selected, there is no way to know if the results would have been biased towards a better or worse figure with respect to the national average. A significant correlation was found with reading experience (the best results were obtained by operators with > 10,000 films read and with > 2,000 films read/year), as which is important because most Italian radiologists reporting mammography usually read a limited number of cases. CONCLUSIONS: These results on such a wide sample of radiologists, possibly representative of the national average, are disappointing, and suggest that the average quality of mammography reporting in Italy may not be up to standards. Thus, we suggest that quality control program for clinical mammography not only test the equipment but include training and accreditation of radiologists.


Assuntos
Competência Clínica , Mamografia , Humanos , Itália , Mamografia/normas , Controle de Qualidade , Sensibilidade e Especificidade
20.
Radiol Med ; 77(6): 626-30, 1989 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-2756179

RESUMO

Aseptic osteonecrosis has been described in many and dissimilar pathologic conditions--most frequently as the aftermath of fractures or dislocations; in falciform anemia, obesity, alcoholism; in diseases requiring constant and heavy corticosteroid therapy, and also following renal transplantation. Many of these pathologies, especially alcoholism, diabetes, uremia, and collagen vascular diseases, have a common denominator: peripheral neuropathy, which is believed to be a pathogenetic factor supporting osteonecrosis. The authors analyze 3 cases of aseptic osteonecrosis of the femoral head in cancer patients treated with vincristine and/or vinblastine. Since in these subjects severe and persistent neuropathy preceded the onset of osteonecrosis, a possible relationship is postulated between the vincristine/vinblastine treatment and the onset of femoral head osteonecrosis, through the pathogenetic mechanism of peripheral neuropathy.


Assuntos
Artropatia Neurogênica/induzido quimicamente , Necrose da Cabeça do Fêmur/etiologia , Vimblastina/efeitos adversos , Vincristina/efeitos adversos , Adulto , Artropatia Neurogênica/complicações , Neoplasias Ósseas/tratamento farmacológico , Feminino , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Linfoma/tratamento farmacológico , Masculino , Neoplasias do Mediastino/tratamento farmacológico , Pessoa de Meia-Idade , Osteoma Osteoide/tratamento farmacológico , Radiografia , Teratoma/tratamento farmacológico
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