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Dive into the research topics where Alberto Ribeiro de Souza Leão is active.

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Featured researches published by Alberto Ribeiro de Souza Leão.


Radiologia Brasileira | 2007

Reprodutibilidade da classificação ultra-sonográfica de Niamey na avaliação da fibrose periportal na esquistossomose mansônica

Germana Titonelli Santos; Danilo Moulin Sales; Alberto Ribeiro de Souza Leão; José Eduardo Mourão Santos; Luciane Aparecida Köpke de Aguiar; Paulo Eugênio Brant; David Carlos Shigueoka; Ramiro Colleoni Neto; Giuseppe D'Ippolito

OBJETIVO: Medir a concordância intra- e interobservador da classificacao ultra-sonografica qualitativa para graduar a fibrose periportal adotada no encontro de Niamey em 1996. MATERIAIS E METODOS: No periodo de fevereiro de 2005 a marco de 2006 foi realizado estudo prospectivo, observacional e transversal em 30 pacientes esquistossomoticos, sem outras hepatopatias associadas, submetidos a ultra-sonografia abdominal e classificados segundo os criterios de Niamey. Os exames foram realizados por dois radiologistas de forma independente em diferentes momentos: durante o exame dinâmico (primeiro momento) e 30 e 90 dias depois (segundo e terceiro momentos) do exame, por meio da documentacao fotografica analisada em estacao de trabalho. A concordância intra- e interobservador foi avaliada pelo teste kappa. RESULTADOS: A concordância intra-observador medida pelo teste kappa foi 0,43 para o observador 1 e 0,57 para o observador 2. A concordância interobservador durante o estudo dinâmico e na avaliacao fotografica foi, respectivamente, de 0,46 e 0,71. CONCLUSAO: O uso do ultra-som para classificar a fibrose periportal segundo o protocolo de Niamey apresentou uma reprodutibilidade que variou de moderada a substancial.


Radiologia Brasileira | 2008

Mensuração do volume de fluxo portal em pacientes esquistossomóticos: avaliação da reprodutibilidade do ultra-som Doppler

Alberto Ribeiro de Souza Leão; José Eduardo Mourão Santos; Danilo Sales Moulin; David Carlos Shigueoka; Ramiro Colleoni; Giuseppe D'Ippolito

OBJECTIVE: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. MATERIALS AND METHODOS: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearsons correlation coefficient. RESULTS: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearsons correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). CONCLUSION: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement.


Radiologia Brasileira | 2009

Avaliação do volume de fluxo portal em pacientes esquistossomóticos: estudo comparativo entre ressonância magnética e ultrassom Doppler

Alberto Ribeiro de Souza Leão; Danilo Moulin Sales; José Eduardo Mourão Santos; Edson Minoru Nakano; David Carlos Shigueoka; Giuseppe D'Ippolito

OBJECTIVE: To evaluate the agreement between Doppler ultrasonography and magnetic resonance imaging as well as the interobserver reproducibility of both methods in the measurement of portal blood flow in schistosomal patients. MATERIALS AND METHODS: A cross-sectional, observational, self-paired study evaluated 21 patients with schistosomiasis mansoni submitted to measurement of portal blood flow with phase-contrast magnetic resonance imaging and Doppler ultrasonography. RESULTS: A poor intermethod agreement was observed (intraclass correlation coefficient: 34.5% [CI 95%]). On the other hand, the interobserver reproducibility was excellent in the evaluation by magnetic resonance imaging (intraclass correlation coefficient: 99.2% [CI 95%] / Pearsons correlation coefficient: 99.2% / portal blood flow = 0.806) and by Doppler ultrasonography (intraclass correlation coefficient: 80.6 to 93.0% [CI 95%] / Pearsons correlation coefficient: 81.6% to 92.7% / portal blood flow = 0.954, 0.758 and 0.749). CONCLUSION: There is a poor intermethod agreement in the measurement of portal blood flow. Nevertheless, contrast-phase magnetic resonance imaging and Doppler ultrasonography demonstrated to be reproducible methods presenting excellent interobserver agreement in the quantification of portal blood flow in patients with hepatosplenic schistosomiasis-related portal hypertension


Radiologia Brasileira | 2007

Avaliação da concordância entre ressonância magnética de ultra-sonografia na classificação de fibrose periportal em esquitossomóticos, segundo a classificação de Niamey

Eduardo Scortegagna Junior; Alberto Ribeiro de Souza Leão; José Eduardo Mourão Santos; Danilo Moulin Sales; David Carlos Shigueoka; Luciane Aparecida Köpke de Aguiar; Paulo Eugênio Brant; Ramiro Colleoni Neto; Durval Rosa Borges; Giuseppe D'Ippolito

OBJECTIVE: To evaluate the reproducibility of magnetic resonance imaging and the agreement between ultrasound and magnetic resonance imaging in the classification of periportal fibrosis in patients with schistosomiasis based on Niameys qualitative criteria. MATERIALS AND METHODS: A prospective, double-blinded study was conducted between February 2005 and June 2006 with 20 patients (10 men and 10 women, with ages ranging between 24 and 60 years, mean age 42.7 years) diagnosed with schistosomiasis mansoni. Both ultrasound and magnetic resonance images were independently evaluated by two experienced observers. Interobserver agreement was evaluated for findings of periportal fibrosis on magnetic resonance images and in a comparison between magnetic resonance and ultrasound images. RESULTS: The analysis of magnetic resonance images showed total interobserver agreement in 14 patients (70%). The comparison between ultrasound and magnetic resonance imaging showed agreement between images in only six cases (30%) by observer 1, and in eight cases (40%) by observer 2. CONCLUSION: Magnetic resonance imaging presents a good reproducibility in the evaluation of periportal fibrosis in later stages of schistosomiasis, however, the correlation between magnetic resonance imaging and ultrasound is poor.


Memorias Do Instituto Oswaldo Cruz | 2010

Interobserver variability of ultrasound parameters in portal hypertension

Patrícia Moreno Sebastianes; Danilo Moulin Sales; José Eduardo Mourão Santos; Alberto Ribeiro de Souza Leão; Juliana Dantas da Costa; Kenji Takemoto; Julia Capobianco; Alexandre Sérgio de Araújo Bezerra; Giuseppe D'Ippolito

The aim of this study was to assess interobserver agreement of ultrasound parameters for portal hypertension in hepatosplenic mansonic schistosomiasis. Spleen size, diameter of the portal, splenic and superior mesenteric veins and presence of thrombosis and cavernous transformation were determined by three radiologists in blinded and independent fashion in 30 patients. Interobserver agreement was measured by the kappa index and intraclass correlation coefficient. Interobserver agreement was considered substantial (kappa = 0.714-0.795) for portal vein thrombosis and perfect (kappa = 1) for cavernous transformation. Interobserver agreement measured by the intraclass correlation coefficient was excellent for longitudinal diameter of the spleen (r = 0.828-0.869) and splenic index (r = 0.816-0.905) and varied from fair to almost perfect for diameter of the portal (r = 0.622-0.675), splenic (r = 0.573-0.913) and superior mesenteric (r = 0.525-0.607) veins. According to the results, ultrasound is a highly reproducible method for the main morphological parameters of portal hypertension in schistosomiasis patients.


Radiologia Brasileira | 2009

Correlação interobservador das alterações morfológicas das vias biliares em pacientes com esquistossomose mansoni pela colangiorressonância magnética

Danilo Moulin Sales; José Eduardo Mourão Santos; David Carlos Shigueoka; Alberto Ribeiro de Souza Leão; Ramiro Colleoni Neto; Durval Rosa Borges; Giuseppe D'Ippolito; Jacob Szejnfeld

OBJECTIVE: To describe changes of the biliary tree demonstrated by magnetic resonance cholangiography (MRC) in patients with the hepatosplenic presentation of schistosomiasis mansoni, and evaluating the interobserver agreement in the detection of schistosomal cholangiopathy. MATERIALS AND METHODS: Prospective, cross-sectional study involving 24 patients with hepatosplenic schistosomiasis and 6 healthy patients (control group) submitted to biliary tree evaluation by MRC. The following changes of the biliary tree were considered: distortion, thinning, stenosis, dilation and irregularity. The interobserver agreement in the detection of biliary tree changes was calculated with the McNemars test and the kappa index of agreement (κ). RESULTS: The interobserver agreement in the detection of distortion and thinning of the biliary tree was almost perfect (κ = 0.867; confidence interval [CI] 95% [0.512-1.0] and κ = 0.865; CI 95% [0.51-1.0], respectively). There was a substantial agreement for stenosis (κ = 0.78; CI 95% [0.424-1.0]), moderate agreement for dilation (κ = 0.595; CI 95% [0.247-0.942]) and mild agreement for thinning (κ = 0.229; CI 95% [0.095-0.552]). CONCLUSION: In a decreasing order of frequency, the changes of the biliary tree were observed: distortion, thinning, stenosis, dilation and irregularity. The interobserver agreement for signs of schistosomal cholangiopathy was almost perfect for distortion and thinning, and substantial for stenosis.


Radiologia Brasileira | 2007

Patologias do compartimento iliopsoas: avaliação radiológica

Alberto Ribeiro de Souza Leão; Raquel Portugal Guimarães Amaral; Thiago Giansante Abud; Guilherme Tadeu Sauaia Demarchi; Edison de Oliveira Freire Filho; Paulo Rogério Novack; Flávio do Amaral Campos; José Eduardo Mourão Santos; David Carlos Shigueoka; Artur da Rocha Corrêa Fernandes; Jacob Szejnfeld; Giuseppe D'Ippolito

The iliopsoas compartment, a posterior boundary of the retroperitoneum, is comprised of the psoas major, psoas minor and iliac muscles. The symptoms picture in patients presenting with pathological involvement of this compartment may show a wide range of nonspecific clinical presentations that may lead to delayed diagnosis. However, in the search of an etiological diagnosis, it is already known that inflammation, tumors, and hemorrhages account for almost all the lesions affecting the iliopsoas compartment. By means of a retrospective analysis of radiological studies in patients with iliopsoas compartment lesions whose diagnosis was confirmed by anatomopathological evaluation or clinical follow-up, we have reviewed its anatomy as well as the main forms of involvement, with the purpose of identifying radiological signs that may help to narrow down the potential differential diagnoses. As each lesion is approached we will discuss the main radiological findings such as presence of gas in pyogenic abscesses, bone destruction and other bone changes of vertebral bodies in lesions secondary to tuberculosis, involvement of fascial planes in cases of neoplasms, and differences in signal density and intensity of hematomas secondary to hemoglobin degradation, among others. So, we have tried to present cases depicting the most frequent lesions involving the iliopsoas compartment, with emphasis on those signs that can lead us to a more specific etiological diagnosis.Limite posterior do retroperitonio, o compartimento iliopsoas localiza-se externamente ao mesmo, sendo composto dos musculos psoas maior, psoas menor e iliaco. O quadro de sintomas dos pacientes com acometimento patologico deste compartimento e amplo e inespecifico, podendo haver importante atraso no diagnostico. Entretanto, na busca do diagnostico etiologico das alteracoes do compartimento iliopsoas, sabemos que as infeccoes, os tumores e as hemorragias respondem pela quase totalidade das lesoes. Por meio da avaliacao retrospectiva de exames radiologicos de pacientes com patologias do iliopsoas e que tiveram o diagnostico confirmado por exame anatomopatologico ou acompanhamento clinico, revisamos a anatomia deste compartimento, assim como as suas principais formas de acometimento, identificando sinais que auxiliem na diferenciacao dos potenciais diagnosticos diferenciais. Na abordagem de cada patologia discutiremos os principais sinais radiologicos, como a presenca de gas em abscessos piogenicos, alteracoes osseas em corpos vertebrais nas lesoes secundarias a tuberculose, comprometimento dos planos fasciais nas lesoes tumorais e diferencas na densidade e intensidade de sinal dos hematomas nas diferentes fases de degradacao da hemoglobina, entre outros. Dessa forma, procuramos apresentar casos que exemplifiquem as doencas mais frequentes do compartimento iliopsoas, destacando a importância dos seus diferentes sinais, aproximando-nos de um diagnostico etiologico especifico.


Radiologia Brasileira | 2006

Definição do nível da junção ureterovesical pela tomografia computadorizada

Edison de Oliveira Freire Filho; Alberto Ribeiro de Souza Leão; Julia Capobianco; Jacob Szejnfeld; Giuseppe D'Ippolito

OBJECTIVE: To define, by means of computed tomography, the level of ureteral implantation into de bladder. MATERIALS AND METHODS: We have measured the distances from the ureteral meatus to the acetabulum, and to the superior margin of the pubic symphysis, as well as the bladder volume, using contrast enhanced computed tomography of the pelvis in 46 patients (31 male and 15 female) in the age range between 18 and 45 years, with at least one of the ureteres filled with excreted contrast material. The Student t test has been applied to determine eventual statistically significant differences between groups. RESULTS: The level of ureteral implantation into the bladder was, on average, 10.6 ± 8.1 mm below the acetabular roof, and 29.7 ± 9.5 mm above the superior margin of the pubic symphysis. In patients with bladder repletion volume of 200 ml, the level of ureteral implantation into the bladder was, respectively, on average, 11.6 ± 7.3 mm and 10.2 ± 8.4 mm below the acetabular roof (p = 0.61), and 28.3 ± 7.3 mm and 30.3 ± 10.2 mm above the superior margin of the pubic symphysis (p = 0.52), and in male and female men patients, respectively, on average, 11.8 ± 8.0 mm and 8.3 ± 8.0 mm below the acetabular roof (p = 0.17), and 27.7 ± 9.2 mm and 33.9 ± 8.8 mm above the superior margin of the pubic symphysis (p = 0.34). CONCLUSION: Calcifications located < 3 cm below the acetabular roof and < 1.5 cm above the superior margin of the pubic symphysis probably do not represent ureteral calculi. Vesical repletion or sex have no significant influence on the ureteral meatus position.


Rev. imagem | 2005

Comprometimento de orgãos sólidos abdominais por linfoma

Edison de Oliveira Freire Filho; Alberto Ribeiro de Souza Leão; Jacob Szejnfeld; Giuseppe D'Ippolito


Rev. imagem | 2005

Aspectos radiológicos das alterações esplênicas: como diferenciá-las

Alberto Ribeiro de Souza Leão; Edison de Oliveira Freire Filho; Jacob Szejnfeld; Giuseppe D´Ippolito

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Giuseppe D'Ippolito

Federal University of São Paulo

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David Carlos Shigueoka

Federal University of São Paulo

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Danilo Moulin Sales

Federal University of São Paulo

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Jacob Szejnfeld

Federal University of São Paulo

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Ramiro Colleoni Neto

Federal University of São Paulo

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Durval Rosa Borges

Federal University of São Paulo

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Julia Capobianco

Federal University of São Paulo

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