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1.
Radiol Med ; 113(8): 1085-95, 2008 Dec.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-18953635

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética , Femenino , Humanos
2.
Phys Med Biol ; 52(5): 1387-407, 2007 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-17301461

RESUMEN

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.


Asunto(s)
Inteligencia Artificial , Mamografía/instrumentación , Mamografía/métodos , Garantía de la Calidad de Atención de Salud/métodos , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Fantasmas de Imagen , Intensificación de Imagen Radiográfica/instrumentación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
3.
Phys Med Biol ; 51(17): 4233-51, 2006 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-16912379

RESUMEN

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).


Asunto(s)
Algoritmos , Medios de Contraste/química , Yodo/química , Técnica de Sustracción , Relación Dosis-Respuesta a Droga , Humanos , Mamografía/instrumentación , Mamografía/métodos , Fantasmas de Imagen , Control de Calidad , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos
5.
Phys Med Biol ; 48(13): 1945-56, 2003 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-12884927

RESUMEN

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.


Asunto(s)
Diagnóstico por Imagen/métodos , Mamografía/instrumentación , Mamografía/métodos , Algoritmos , Calibración , Medios de Contraste/farmacología , Modelos Estadísticos , Fantasmas de Imagen , Rayos X
6.
J Exp Clin Cancer Res ; 21(3 Suppl): 115-24, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12585665

RESUMEN

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.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Imagen por Resonancia Magnética , Tamizaje Masivo , Adulto , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Reacciones Falso Positivas , Femenino , Gadolinio , Genes BRCA1 , Genes BRCA2 , Predisposición Genética a la Enfermedad , Humanos , Mamografía , Tamizaje Masivo/economía , Persona de Mediana Edad , Mutación , Estudios Prospectivos , Intensificación de Imagen Radiográfica , Ultrasonografía Mamaria
8.
Am J Psychiatry ; 158(3): 489-92, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11229996

RESUMEN

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.


Asunto(s)
Esquizofrenia/epidemiología , Adulto , Factores de Edad , Edad de Inicio , Efecto de Cohortes , Estudios de Cohortes , Comorbilidad , Familia , Femenino , Francia/epidemiología , Registros de Hospitales/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Modelos Genéticos , Prevalencia , Estudios Retrospectivos , Esquizofrenia/diagnóstico , Esquizofrenia/genética , Trastornos Relacionados con Sustancias/diagnóstico , Trastornos Relacionados con Sustancias/epidemiología
9.
Radiol Med ; 98(4): 255-8, 1999 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-10615363

RESUMEN

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.


Asunto(s)
Competencia Clínica , Mamografía , Humanos , Italia , Mamografía/normas , Control de Calidad , Sensibilidad y Especificidad
11.
Radiol Med ; 92(6): 677-81, 1996 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-9122453

RESUMEN

To study ankle and hindfoot involvement, we used Computed Tomography (CT) in 38 rheumatoid arthritis (RA) patients (32 women, 6 men, mean age: 56.3 +/- 10.1 years, mean disease duration: 9.9 +/- 6 years) all presenting a definite clinical disease of these joints. The scans were performed on 3rd generation CT equipment (GE ProSpeed SX), with coronally oriented scans 3 mm thick. Bone erosions and joint space narrowing (present/absent) of both talocrural and posterior talocalcaneal joints were assessed and heel valgus angle was measured. Ankle changes (erosion plus joint narrowing) were observed in 15 patients (39.5%, 17 of 76 lower limbs), talocalcaneal changes in 18 (47.4%, 31 lower limbs) and valgus deformity of the hindfoot in 22 (57.9%, 40 lower limbs). Involvement of talocrural and talocalcaneal joints as well as alignment abnormalities were symmetrical in 13.3%, 77.8% and 81.8% of the cases, respectively. All the CT findings were significantly related to disease duration (p = 0.02) and hindfoot injuries to Ritchie index too (p < 0.05). No relationship with seropositivity was observed. Our study confirms that radiographic changes do not entirely mirror clinical evidence and shows that CT does not represent a routine examination for RA patients, but could be reserved to those with prolonged disease or severe heel deformity to plan surgery.


Asunto(s)
Artritis Reumatoide/diagnóstico por imagen , Articulaciones Tarsianas/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X
12.
Radiol Med ; 92(3): 261-6, 1996 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-8975313

RESUMEN

The authors tested a new equipment containing a phantom to check quality mammographic image and an electronic instrument to measure incident radiation (Phan-EX). The phantom contains objects which have similar characteristics to the details of diagnostic interest and allows an easy and accurate estimation of image quality on the basis of the number of objects detected. The radiation detector, consisting of a solid state photodiode, provides an integer proportional to the input exposure. The results obtained highlighted a good reproducibility of instrument output and a good relationship between these values and the exposure ones obtained with a much more expensive ionization chamber. The device response was linear in varying both the anodic exposure (mAs) and the x-ray tube voltage (varying the energy, the calibration factor varied only by a small percent). The authors conclude that the Phan-EX may be useful for quality assurance of the mammographic unit. Furthermore, they suggest some of its practical applications: daily tests of qualitative of the mammographic unit and the treatment system performance, control of the automatic exposure probe, choice and optimization of exposure and treatment of the film parameters, the determination of the output of the x-ray tube, the evaluation of the sensitivity of different screen/film systems.


Asunto(s)
Mamografía/instrumentación , Mamografía/normas , Diseño de Equipo , Modelos Teóricos , Control de Calidad
14.
Radiology ; 195(1): 239-44, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7892478

RESUMEN

PURPOSE: To determine the feasibility of using synchrotron radiation (SR) in diagnostic mammography. MATERIALS AND METHODS: Monochromatic SR of x-ray beams of selected energies of 14-20 keV were used to obtain mammograms of surgically removed breast specimens that contained tumor nodules. For comparison, conventional mammograms of the same specimens were also obtained. RESULTS: The mammograms obtained with SR had higher contrast and better resolution than did traditional mammograms and demonstrated excellent detail in all cases studied. The mean glandular doses at 17 and 18 keV were 1.56 and 0.83 mGy, respectively, which is compatible with the mean value of 1.41 mGy delivered with the conventional grid apparatus. CONCLUSION: SR mammography appears to be a promising diagnostic imaging technique.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mamografía/métodos , Sincrotrones , Animales , Diseño de Equipo , Femenino , Humanos , Lagartos , Mamografía/instrumentación , Modelos Estructurales , Dosis de Radiación , Tecnología Radiológica
15.
J Ultrasound Med ; 13(11): 855-62, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7837332

RESUMEN

The objective of this study was to verify the accuracy of ultrasonography in assessing the topography, morphology, and extent of synovial proliferation in rheumatoid and psoriatic knee joint synovitis. Findings were compared to those obtained using prospective arthroscopy as the gold standard; in addition, topographically defined sonographic findings before and after arthroscopic synovectomy were compared. Sonographic examination was performed in 12 patients with rheumatoid arthritis (13 knees) and 13 patients with psoriatic arthritis (14 knees) who had synovitis of the knee using an electronic linear transducer (7.5 MHz) or a mechanical sector transducer (10 MHz). This examination was followed within 1 week by arthroscopy, to compare the topography (intra-articular localization) and the morphology (sonographic patterns) of synovial proliferation. In 15 knees undergoing arthroscopic synovectomy, preoperative sonographic measurement of synovial thickness in the suprapatellar, medial parapatellar, and lateral parapatellar recesses was compared with arthroscopic visualization of synovial proliferation; 13 knees were reevaluated 2 months after arthroscopic synovectomy by sonography at the same sites. Three distinct sonographic patterns of synovial proliferation were confirmed by arthroscopic examination: a villonodular aspect in 12 knees; uniform thickening in eight knees, and overlapping layers in seven knees. About 50% of the knees showed more than one sonographic pattern, with no differences in pattern distribution between rheumatoid arthritis and psoriatic arthritis patients. A significant correlation was found between sonographic and arthroscopic evaluations of synovial thickness in the suprapatellar (P < 0.02) and medial parapateoffr recesses (P < 0.02), the sites of maximal synovial proliferation in our patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Artroscopía , Articulación de la Rodilla/diagnóstico por imagen , Sinovitis/diagnóstico por imagen , Adolescente , Adulto , Anciano , Artritis Psoriásica/complicaciones , Artritis Reumatoide/complicaciones , Femenino , Humanos , Articulación de la Rodilla/patología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sinovectomía , Membrana Sinovial/patología , Sinovitis/diagnóstico , Sinovitis/etiología , Sinovitis/cirugía , Ultrasonografía
17.
Radiol Med ; 84(3): 193-7, 1992 Sep.
Artículo en Italiano | MEDLINE | ID: mdl-1410662

RESUMEN

The Breast Section of the Italian Society of Radiology set up a cooperative study which included 17 Departments of Radiology and Breast Diagnosis in order to evaluate the diagnostic accuracy of US versus mammography in nonpalpable breast lesions. From January 1, 1989 to december 31, 1990, 400 nonpalpable breast lesions (142 benign lesions, 59 in situ and 199 infiltrating carcinomas) were detected by mammography and/or US; they had questionable/suspicious findings which called for further investigation by means of cytology and/or histology. US proved much less sensitive in non-palpable carcinomas than mammography (49.2% vs 93.8%), also in younger women, and failed to detect 50% of the benign/malignant nonpalpable lesions identified by mammography. US sensitivity was directly related to lesion diameter and probe frequency: 38.7% in infiltrating carcinomas < or = 5 mm vs 56.8% in those > 10 mm; 12% in the patients examined with a 5-MHz probe vs 57.7% in those examined with a > or = 7.5-MHz probe. Furthermore, the most significant US patterns of nonpalpable lesion were irregular contours, posterior attenuation and irregular internal echoes, while an irregular skin line and Cooper ligaments had no significant relation with carcinoma. Thus, breast US cannot be used as a screening test on asymptomatic patients not even on young women with radiologically dense breasts. On the contrary, US performed with high-frequency probes is useful in the assessment of nonpalpable lesions identified by mammography, and allows, in many cases, US-guided cytology and preoperative localization.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Mamografía , Ultrasonografía Mamaria , Adulto , Carcinoma/diagnóstico , Carcinoma in Situ/diagnóstico , Estudios de Evaluación como Asunto , Femenino , Humanos , Italia , Persona de Mediana Edad , Sensibilidad y Especificidad
19.
Radiol Med ; 83(3): 206-8, 1992 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-1579665

RESUMEN

The authors compare the accuracy and other indicators of efficiency of ten centers (1,784 total cases) performing stereotaxic cytology and adhering to a multicentric study aimed at validating a quality control system for this diagnostic procedure. The results from single centers were compared with average results. No significant differences were observed for most centers from the average sensitivity (86%), specificity (91%), positive predictive value of a dubious (57%) or positive (96%) cytologic report, inadequacy rate on malignant (6%) or benign (11%) lesions, and benign/malignant biopsy ratio (0.63). Some significant differences from the average values indicated the need for some centers to review different phases of the diagnostic process, namely to verify the accuracy of sampling sites (low sensitivity with good specificity and predictivity), to review the criteria for cytologic diagnosis (specificity less than 90%, low predictive value or higher predictive value for dubious compared with positive reports), to optimize the impact of cytology on the final decision (lack of reduction of benign/malignant biopsy ratio). Periodic check of the above parameters is proposed as a routine quality control of this diagnostic procedure.


Asunto(s)
Enfermedades de la Mama/patología , Neoplasias de la Mama/patología , Técnicas Estereotáxicas , Estudios de Seguimiento , Humanos , Valor Predictivo de las Pruebas , Control de Calidad , Sensibilidad y Especificidad
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