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1.
Phys Med Biol ; 63(23): 235021, 2018 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-30511662

RESUMO

Texture analysis (TA) applied to CT imaging is an intensely studied topic and many studies suggested TA potential value in imaging characterisation for diagnostic purposes in different fields. However, often authors do not consider the reproducibility and the robustness versus variations in acquisition parameters; in this work, we wanted to explore the robustness of the TA features extracted from CT images. We scanned a commercial phantom (CIRS model 062M) containing plugs with nine different tissue equivalent electron densities using two different CT scanners of the same vendor and changing tube current (100 and 200 mA without modulation) and peak voltage (80 and 140 kVp). After the segmentation, we extracted TA features with LifeX and data were then statistically analysed using the generic estimate equations (GEE) method. Our results suggest that only seven out of 37 TA features extracted are not affected by variation in acquisition parameters considered in this study: GLRLM lgre, GLRLM srlge, GLRLM lrgle, GLZLM lze, GLZLM lgze, GLZLM szlge, GLZLM lzlge. Definitively, we highlighted the importance of a careful study of the dependence of TA parameters on acquisition modalities and analysis before their application in clinical studies.


Assuntos
Tomografia Computadorizada por Raios X/métodos , Algoritmos , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/instrumentação
2.
Osteoporos Int ; 28(6): 1915-1923, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28243706

RESUMO

This study deals with the role of texture analysis as a predictive factor of radiation-induced insufficiency fractures in patients undergoing pelvic radiation. INTRODUCTION: This study aims to assess the texture analysis (TA) of computed tomography (CT) simulation scans as a predictive factor of insufficiency fractures (IFs) in patients with pelvic malignancies undergoing radiation therapy (RT). METHODS: We performed an analysis of patients undergoing pelvic RT from January 2010 to December 2014, 24 of whom had developed pelvic bone IFs. We analyzed CT-simulation images using ImageJ macro software and selected two regions of interest (ROIs), which are L5 body and the femoral head. TA parameters included mean (m), standard deviation (SD), skewness (sk), kurtosis (k), entropy (e), and uniformity (u). The IFs patients were compared (1:2 ratio) with controlled patients who had not developed IFs and matched for sex, age, menopausal status, type of tumor, use of chemotherapy, and RT dose. A reliability test of intra- and inter-reader ROI TA reproducibility with the intra-class correlation coefficient (ICC) was performed. Univariate and multivariate analyses (logistic regression) were applied for TA parameters observed both in the IFs and the controlled groups. RESULTS: Inter- and intra-reader ROI TA was highly reproducible (ICC > 0.90). Significant TA parameters on paired t test included L5 m (p = 0.001), SD (p = 0.002), k (p = 0.006), e (p = 0.004), and u (p = 0.015) and femoral head m (p < 0.001) and SD (p = 0.001), whereas on logistic regression analysis, L5 e (p = 0.003) and u (p = 0.010) and femoral head m (p = 0.027), SD (p = 0.015), and sex (p = 0.044). CONCLUSIONS: In our experience, bone CT TA could be correlated to the risk of radiation-induced IFs. Studies on a large patient series and methodological refinements are warranted.


Assuntos
Fraturas de Estresse/etiologia , Ossos Pélvicos/lesões , Lesões por Radiação/etiologia , Radioterapia de Alta Energia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Colo do Fêmur/diagnóstico por imagem , Fraturas de Estresse/diagnóstico por imagem , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Ossos Pélvicos/efeitos da radiação , Neoplasias Pélvicas/radioterapia , Valor Preditivo dos Testes , Lesões por Radiação/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Dosagem Radioterapêutica , Radioterapia de Alta Energia/métodos , Medição de Risco/métodos , Tomografia Computadorizada por Raios X/métodos
3.
Eur J Surg Oncol ; 43(4): 642-648, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27889196

RESUMO

BACKGROUND: Core needle biopsy (CNB) plays a crucial role as diagnostic tool for breast cancer (BC). The characterization of biomarkers status before surgical treatment is crucial when primary systemic therapy is a therapeutic option. The aim of this analysis was to report concordance between preoperative CNB and surgical specimen (SS) in evaluating biomarkers and molecular subtypes. METHODS: Data have been collected from a cohort of 101 patients affected by early BC treated at Careggi Florence University Hospital, between January 2014 and March 2015. The conformity between molecular subtype classification was tested using kappa (κ) test. RESULTS: Mean age was 57.5 years (range 29-86). There was concordance between the estrogen receptor (ER) assessment on CNB and SS in 95 cases (94.1%). Concordance of the progesterone receptor (PgR) assessment was observed in 89 cases (88.1%). Concordance for detecting immunohistochemistry-assessed BC molecular subtypes was 87.1% (κ = 0.78). Concerning Ki-67 evaluation, we report a concordance rate of 88.1% (κ = 0.68). The evaluation of luminal A plus luminal B/HER negative subgroup showed a κ-value of 0.65. CONCLUSIONS: CNB showed good accuracy in evaluating hormonal receptors status, HER2, and BC molecular subtypes. Evaluation of Ki67 status was less accurate than other biomarkers; therefore, we recommend that it should be detected both on CNB and SS samples, especially in hormonal positive HER2 negative tumors, in order to avoid a misclassification of tumor subtypes that could lead to an omission of potential effective systemic therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/patologia , Carcinoma Lobular/terapia , Gerenciamento Clínico , Feminino , Humanos , Biópsia Guiada por Imagem , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/terapia , Ultrassonografia Mamária
4.
Eur J Surg Oncol ; 43(4): 680-682, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27567098

RESUMO

The importance of preoperative histological diagnosis in the assessment of breast lesions in women is widely established, but in men with breast lesions histological diagnosis is obtained in a limited number of cases. The aim of this study was to report our single-center experience in a large series of 131 CNB performed for suspicious male breast lesions. Our data confirmed that CNB is an effective method in distinguishing between benign and neoplastic lesions in the male breast, thus validating the few published data. CNB should be a routine part of the unilateral male breast swelling diagnostic assessment, being precious tool for the clinicians for surgery planning or avoidance.


Assuntos
Neoplasias da Mama Masculina/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Carcinoma Papilar/patologia , Ginecomastia/patologia , Mastite/patologia , Neoplasias Unilaterais da Mama/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Biópsia com Agulha de Grande Calibre , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Phys Med ; 32(12): 1712-1716, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27524684

RESUMO

INTRODUCTION: Many studies aimed at validating the application of Dual Energy Computed Tomography (DECT) in clinical practice where conventional CT is not exhaustive. An example is given by bone marrow oedema detection, in which DECT based on water/calcium (W/Ca) decomposition was applied. In this paper a new DECT approach, based on water/cortical bone (W/CB) decomposition, was investigated. MATERIALS AND METHODS: Eight patients suffering from marrow oedema were scanned with MRI and DECT. Two-materials density decomposition was performed in ROIs corresponding to normal bone marrow and oedema. These regions were drawn on DECT images using MRI informations. Both W/Ca and W/CB were considered as material basis. Scatter plots of W/Ca and W/CB concentrations were made for each ROI in order to evaluate if oedema could be distinguished from normal bone marrow. Thresholds were defined on the scatter plots in order to produce DECT images where oedema regions were highlighted through color maps. The agreement between these images and MR was scored by two expert radiologists. RESULTS: For all the patients, the best scores were obtained using W/CB density decomposition. CONCLUSIONS: In all cases, DECT color map images based on W/CB decomposition showed better agreement with MR in bone marrow oedema identification with respect to W/Ca decomposition. This result encourages further studies in order to evaluate if DECT based on W/CB decomposition could be an alternative technique to MR, which would be important when short scanning duration is relevant, as in the case of aged or traumatic patients.


Assuntos
Medula Óssea/diagnóstico por imagem , Osso Cortical/diagnóstico por imagem , Osso Cortical/metabolismo , Edema/diagnóstico por imagem , Edema/metabolismo , Tomografia Computadorizada por Raios X , Água/metabolismo , Adulto , Idoso , Medula Óssea/metabolismo , Estudos de Viabilidade , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
6.
Eur J Surg Oncol ; 40(7): 859-64, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24612651

RESUMO

AIMS: Image-guided 14-gauge (G) core biopsy (CB) has been shown to be an accurate method providing histological diagnosis of breast lesions. The purpose of this study was to evaluate the reliability of image-guided 14-G CB in the diagnosis of phyllodes tumours (PT) reported as B3 category and its accuracy in distinguishing this lesion from fibroadenomas (FA). MATERIALS AND METHODS: The records of 10 000 image-guided 14-G CB of the breast performed from January 2001 to August 2011 at the Diagnostic Senology Unit of Careggi University Hospital were reviewed; 2554 (25.5%) were fibroepithelial lesions: 56 of them (2%) were diagnosed as PT and reported as B3 category. The database of the Pathological Anatomy Unit of Careggi University Hospital was then searched to verify the histological diagnosis after surgical excision. Fifty-one cases of PT diagnosed as B3 category in 51 women were included in the present study. RESULTS: Of the 51 cases of PT diagnosed as B3 category on 14-G CB, 39 (76.5%) lesions were confirmed as PT on SE (30, 4 and 5 as benign, borderline and malignant PT respectively) with a PPV of 76.5%. Twelve lesions (23.5%) were diagnosed as FA after surgical excision. CONCLUSIONS: Our study shows that 14-G CB is a valuable tool, in a preoperative setting, in diagnosing PT.


Assuntos
Biópsia com Agulha de Grande Calibre , Neoplasias da Mama/patologia , Fibroadenoma/patologia , Biópsia Guiada por Imagem/métodos , Tumor Filoide/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Estudos de Coortes , Diagnóstico Diferencial , Feminino , Fibroadenoma/diagnóstico , Fibroadenoma/cirurgia , Hospitais Universitários , Humanos , Imuno-Histoquímica , Itália , Mastectomia/métodos , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Tumor Filoide/diagnóstico , Tumor Filoide/cirurgia , Cuidados Pré-Operatórios/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos
7.
Eur J Surg Oncol ; 40(3): 277-81, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24388742

RESUMO

BACKGROUND: The dislocation of the malignant cells along the needle tract during breast cancer (BC) diagnosis has been demonstrated by several studies. However, the published experiences that relate the diagnostic technique with sentinel node (SN) involvement are few and controversial. The aim of our analysis was to evaluate the impact of different techniques for preoperative BC biopsy among prognostic factors of metastases occurrence in SN. MATERIALS AND METHODS: We reviewed the institutional clinical database of our Center. A total of 674 patients were diagnosed between February 1999 and December 2006 with invasive BC. SN metastases classification followed the 2002 American Joint Committee on Cancer (AJCC) TNM pathological staging: macrometastases, micrometastases, isolated tumor cells or negative. Only macrometastases and micrometastases were considered positive. Concerning fine-needle aspiration cytology, we used disposable needles of the size of 21-27 G. For percutaneous biopsy we used cutting needle type "tru-cut"; the Gauge needle ranged between 14 and 20. RESULTS: At univariate analysis of specific parameters using positive SN as outcome, percutaneous diagnostic technique did not affect significantly the SN positivity (p = 0.60). At multivariate models only central quadrant lesion (p = 0.005) and lymph vascular invasion (LVI) presence (p < 0.0001) maintained the statistical significance as risk factor for positive SN status. Polytomic logistics models showed that only LVI maintained the statistical significance both for prediction of micrometastases and macrometastases. CONCLUSIONS: Our analysis showed that different techniques used for BC diagnosis did not influence SN status.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/secundário , Micrometástase de Neoplasia/patologia , Inoculação de Neoplasia , Biópsia de Linfonodo Sentinela/efeitos adversos , Biópsia de Linfonodo Sentinela/métodos , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biópsia por Agulha Fina/efeitos adversos , Biópsia por Agulha Fina/métodos , Neoplasias da Mama/mortalidade , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/mortalidade , Carcinoma Intraductal não Infiltrante/cirurgia , Distribuição de Qui-Quadrado , Estudos de Coortes , Bases de Dados Factuais , Equipamentos Descartáveis , Feminino , Humanos , Imuno-Histoquímica , Incidência , Linfonodos/patologia , Metástase Linfática , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/patologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Análise de Sobrevida
8.
Q J Nucl Med Mol Imaging ; 56(3): 299-308, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22695340

RESUMO

AIM: Previous positron emission tomography (PET) [18F]fluorodeoxyglucose ([18F]FDG) studies in Parkinson's disease (PD) demonstrated that moderate to late stage patients display widespread cortical hypometabolism, whereas early stage PD patients exhibit little or no cortical changes. However, recent studies suggested that conventional data normalization procedures may not always be valid, and demonstrated that alternative normalization strategies better allow detection of low magnitude changes. We hypothesized that these alternative normalization procedures would disclose more widespread metabolic alterations in de novo PD. METHODS: [18F]FDG PET scans of 26 untreated de novo PD patients (Hoehn & Yahr stage I-II) and 21 age-matched controls were compared using voxel-based analysis. Normalization was performed using gray matter (GM), white matter (WM) reference regions and Yakushev normalization. RESULTS: Compared to GM normalization, WM and Yakushev normalization procedures disclosed much larger cortical regions of relative hypometabolism in the PD group with extensive involvement of frontal and parieto-temporal-occipital cortices, and several subcortical structures. Furthermore, in the WM and Yakushev normalized analyses, stage II patients displayed more prominent cortical hypometabolism than did stage I patients. CONCLUSION: The use of alternative normalization procedures, other than GM, suggests that much more extensive cortical hypometabolism is present in untreated de novo PD patients than hitherto reported. The finding may have implications for our understanding of the basic pathophysiology of early-stage PD.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Idoso , Estudos de Casos e Controles , Feminino , Fluordesoxiglucose F18 , Glucose/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade
9.
Breast ; 21(2): 159-64, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21944431

RESUMO

The purpose of this study was to evaluate the reliability of image-guided 14-gauge needle core biopsy in the diagnosis of radial scar without associated atypical epithelial proliferation, by comparison with definitive histological diagnosis on surgical excision. The records of 8792 consecutive image-guided 14-gauge needle core biopsy of the breast performed from January 1996 to December 2009 were reviewed. Forty-nine cases of radial scar without associated atypical epithelial proliferation were identified and compared with definitive histological diagnosis on surgical excision. The definitive histological diagnosis on surgical excision confirmed the results of image-guided 14-gauge needle core biopsy in 36 of 49 cases (73.5%), in 9 cases (18.3%) radial scar was associated with atypical epithelial proliferation, while 4 cases out of 49 cases were upgraded to carcinoma (3 cases of ductal carcinoma in situ and one case of invasive lobular carcinoma), with an underestimation rate of 8.2%. A diagnosis of radial scar without associated atypical epithelial proliferation on image-guided 14-gauge needle core biopsy does not exclude a malignancy on surgical excision; consequently during the multidisciplinary discussion further assessment by surgical excision or vacuum-assisted excision, as recently reported, needs to be considered to obtain a definitive histological diagnosis.


Assuntos
Doenças Mamárias/diagnóstico , Neoplasias da Mama/patologia , Mama/patologia , Carcinoma in Situ/patologia , Cicatriz/diagnóstico , Adulto , Idoso , Biópsia por Agulha , Doenças Mamárias/patologia , Proliferação de Células , Cicatriz/patologia , Células Epiteliais , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
10.
Phys Rev Lett ; 93(23): 232701, 2004 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-15601152

RESUMO

Peripheral and semiperipheral collisions have been studied in the system 93Nb+93Nb at 38A MeV. The evaporative and midvelocity components of the light charged particle and intermediate mass fragment emissions have been carefully disentangled. In this way it was possible to obtain the average amount not only of charge and mass, but also of energy, pertaining to the midvelocity emission, as a function of an impact parameter estimator. This emission has a very important role in the overall balance of the reaction, as it accounts for a large fraction of the emitted mass and for more than half of the dissipated energy. As such, it may give precious clues on the microscopic mechanism of energy transport from the interaction zone toward the target and projectile remnants.

11.
Ital J Anat Embryol ; 105(1): 1-50, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10829568

RESUMO

We measured by ultrasound the spleen, the kidneys, the pancreas in 323 children (age 0-12), the thyroid in 60 children of same age range, and all these organs in 180 adults (in adults we measured additionally the testis, the gallbladder and the choledochus). Children and adults were all healthy, without evidence of pathologies potentially involving these organs. The children have been selected looking at clinical and hematological parameters, while the adults have been selected among a military population, that is the most significant sample of healthy young adults. We measured the length, the transversal diameter and the thickness of the spleen, kidneys, pancreas, testis and thyroid, the diameter of the choledochus and the maximum length of the gallbladder (pre and post stimulus). We found a good correlation between age and dimensions for pancreas, kidneys and spleen in children, representing the progressive growth of these organs. Our data represent an assessment of the normal dimensions of these organs in vivo by means of ultrasound, and therefore they are an useful tool to discriminate pathologically enlarged or reduced organs, both in children and in adults.


Assuntos
Ducto Colédoco/diagnóstico por imagem , Vesícula Biliar/diagnóstico por imagem , Rim/diagnóstico por imagem , Pâncreas/diagnóstico por imagem , Baço/diagnóstico por imagem , Testículo/diagnóstico por imagem , Adolescente , Adulto , Envelhecimento , Criança , Pré-Escolar , Ducto Colédoco/anatomia & histologia , Ducto Colédoco/crescimento & desenvolvimento , Feminino , Vesícula Biliar/anatomia & histologia , Vesícula Biliar/crescimento & desenvolvimento , Humanos , Lactente , Recém-Nascido , Rim/anatomia & histologia , Rim/crescimento & desenvolvimento , Masculino , Pâncreas/anatomia & histologia , Pâncreas/crescimento & desenvolvimento , Valores de Referência , Baço/anatomia & histologia , Baço/crescimento & desenvolvimento , Testículo/anatomia & histologia , Testículo/crescimento & desenvolvimento , Ultrassonografia
12.
Radiology ; 210(2): 399-403, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10207421

RESUMO

PURPOSE: To compare the performance of artificial neural networks (ANNs) with that of multiple logistic regression (MLR) models for predicting ovarian malignancy in patients with adnexal masses by using transvaginal B-mode and color Doppler flow ultrasonography (US). MATERIALS AND METHODS: A total of 226 adnexal masses were examined before surgery: Fifty-one were malignant and 175 were benign. The data were divided into training and testing subsets by using a "leave n out method." The training subsets were used to compute the optimum MLR equations and to train the ANNs. The cross-validation subsets were used to estimate the performance of each of the two models in predicting ovarian malignancy. RESULTS: At testing, three-layer back-propagation networks, based on the same input variables selected by using MLR (i.e., women's ages, papillary projections, random echogenicity, peak systolic velocity, and resistance index), had a significantly higher sensitivity than did MLR (96% vs 84%; McNemar test, p = .04). The Brier scores for ANNs were significantly lower than those calculated for MLR (Student t test for paired samples, P = .004). CONCLUSION: ANNs might have potential for categorizing adnexal masses as either malignant or benign on the basis of multiple variables related to demographic and US features.


Assuntos
Redes Neurais de Computação , Neoplasias Ovarianas/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adulto , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Neoplasias Ovarianas/epidemiologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores/estatística & dados numéricos
13.
Br J Obstet Gynaecol ; 105(8): 917-20, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9746387

RESUMO

The aim of this study was to evaluate the potential effectiveness of maternal serum pregnancy-associated plasma protein A (PAPP-A) and free beta-hCG in combination with nuchal translucency thickness in first trimester screening for Down's syndrome. Maternal serum levels of PAPP-A and free beta-hCG were assayed in stored sera from 32 Down's syndrome and 200 unaffected pregnancies. Fetal nuchal translucency was measured by ultrasound at the time of blood sampling. Screening of Down's syndrome using a combination of maternal age, PAPP-A, free beta-hCG and nuchal translucency would achieve a detection rate of 75.8% for a false positive rate of 5%.


Assuntos
Gonadotropina Coriônica/sangue , Síndrome de Down/diagnóstico , Pescoço/embriologia , Proteína Plasmática A Associada à Gravidez/análise , Diagnóstico Pré-Natal/métodos , Adulto , Síndrome de Down/sangue , Reações Falso-Positivas , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Sensibilidade e Especificidade
14.
Ultrasound Obstet Gynecol ; 9(4): 248-52, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9168573

RESUMO

Our purpose was to compare two different methods of expressing nuchal translucency (NT) measurements in first-trimester screening for trisomy 21: the difference in millimeters from the median of nuchal translucency (delta value: delta NT) and the multiple of the expected median (MoM). Fetal nuchal translucency was measured in 32 fetuses with trisomy 21 and in 3180 normal fetuses at 9-13 weeks' gestation. For each fetus, the measured nuchal translucency was expressed both as a delta value and MoM. The effectiveness of the MoM-Gaussian vs. the delta value method in modifying the age-specific risk for trisomy 21 was compared by using both the maternal age distribution of our study population and the age distribution of a general obstetric population. The use of the MoM-Gaussian approach led to a reduction in the false-positive rate at a given detection rate, both in the study population (by 1.2-15.2%) and in the general population (by 0.4-2.4%). Our results suggest that the use of the MoM-Gaussian method might confer a potential advantage on the screening performance of nuchal translucency in combination with maternal age by decreasing the false-positive rate. Further studies in larger unselected populations will be needed to confirm the effectiveness of this approach.


Assuntos
Aberrações Cromossômicas/diagnóstico , Síndrome de Down/diagnóstico , Ultrassonografia Pré-Natal/métodos , Adulto , Fatores Etários , Transtornos Cromossômicos , Síndrome de Down/diagnóstico por imagem , Síndrome de Down/genética , Feminino , Idade Gestacional , Humanos , Cariotipagem , Pessoa de Meia-Idade , Gravidez , Primeiro Trimestre da Gravidez , Diagnóstico Pré-Natal , Fatores de Risco
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