Magnetic resonance imaging and previous cesarean section in placenta accrete spectrum disorder: Predictor model.

OBJECTIVE: To evaluate objective criteria of Magnetic Resonance Imaging (MRI) of Placenta Accreta Spectrum disorder (PAS) analyzing interobserver agreement and to derive a model including imaging and clinical variables to predict PAS. METHODS: A retrospective review including patients submitted to MRI with suspicious findings of PAS on ultrasound. Exclusion criteria were lack of pathology or surgical information and missing or poor-quality MRI. Two radiologists analyzed six MRI features, and significant clinical data were also recorded. PAS confirmed on pathology or during intraoperative findings were considered positive for the primary outcome. Variables were tested through logistic regression models. RESULTS: Final study included 96 patients with a mean age of 33 years and 73.0% of previous C-sections. All MRI features were significantly associated with PAS for both readers. After logistic regression fit, including MRI signs with a moderate or higher interobserver agreement, intraplacental T2 dark band was the most significant radiologic criteria, and ROC analysis resulted in an AUC = 0.782. After including the most relevant clinical data (previous C-section) to the model, the ROC analysis improved to an AUC = 0.893. CONCLUSION: Simplified objective criteria on MRI, including intraplacental T2 dark band associated with clinical information of previous C-sections, had the highest accuracy and was used for a predictive model of PAS.

Enhancement patterns of adrenal nodules on magnetic resonance imaging

ABSTRACT Objective: To compare enhancement patterns of typical adrenal adenomas, lipid-poor adenomas, and non-adenomas on magnetic resonance imaging (MRI). Materials and Methods: Evaluation of adrenal nodules larger than 1.0 cm, with at least 2-year follow-up, evaluated on MRI in January 2007 and December 2016. Two different protocols were included - upper abdomen MRI (delayed phase after 3 minutes) and abdomen and pelvis MRI (delayed phase after 7 minutes) - and nodules were divided in typical adenomas (characterized on out-of-phase MRI sequence), lipid-poor adenomas (based on follow-up imaging stability) and non-adenomas (based on pathological finding or follow-up imaging). T2-weighted and enhancement features were analyzed (absolute and relative washout and enhancement curve pattern), similarly to classic computed tomography equations. Results: Final cohort was composed of 123 nodules in 116 patients (mean diameter of 1.8 cm and mean follow up time of 4 years and 3 months). Of them, 98 (79%) nodules had features of typical adenomas by quantitative chemical shift imaging, and demonstrated type 3 curve pattern in 77%, mean absolute and relative washout of 29% and 16%, respectively. Size, oncologic history and T2-weighted features showed statistically significant differences among groups. Also, a threshold greater than 11.75% for absolute washout on MRI achieved sensitivity of 71.4% and specificity of 70.0%, in differentiating typical adenomas from non-adenomas. Conclusion: Calculating absolute washout of adrenal nodules on MRI may help identifying proportion of non-adenomas.

Enhancement patterns of adrenal nodules on magnetic resonance imaging.

OBJECTIVE: To compare enhancement patterns of typical adrenal adenomas, lipid-poor adenomas, and non-adenomas on magnetic resonance imaging (MRI). MATERIALS AND METHODS: Evaluation of adrenal nodules larger than 1.0 cm, with at least 2-year follow-up, evaluated on MRI in January 2007 and December 2016. Two different protocols were included - upper abdomen MRI (delayed phase after 3 minutes) and abdomen and pelvis MRI (delayed phase after 7 minutes) - and nodules were divided in typical adenomas (characterized on out-of-phase MRI sequence), lipid-poor adenomas (based on follow-up imaging stability) and non-adenomas (based on pathological finding or follow-up imaging). T2-weighted and enhancement features were analyzed (absolute and relative washout and enhancement curve pattern), similarly to classic computed tomography equations. RESULTS: Final cohort was composed of 123 nodules in 116 patients (mean diameter of 1.8 cm and mean follow up time of 4 years and 3 months). Of them, 98 (79%) nodules had features of typical adenomas by quantitative chemical shift imaging, and demonstrated type 3 curve pattern in 77%, mean absolute and relative washout of 29% and 16%, respectively. Size, oncologic history and T2-weighted features showed statistically significant differences among groups. Also, a threshold greater than 11.75% for absolute washout on MRI achieved sensitivity of 71.4% and specificity of 70.0%, in differentiating typical adenomas from non-adenomas. CONCLUSION: Calculating absolute washout of adrenal nodules on MRI may help identifying proportion of non-adenomas.

Adrenal cysts of lymphatic origin: A clinical and pathological study of six cases and systematic literature review.

Adrenal cysts are rare, benign, and usually asymptomatic, being detected as an incidental finding on imaging methods. Adrenal Cysts of Lymphatic Origin (ACLO) and Adrenal Lymphangiomas (AL) are types of endothelial cyst and are the most prevalent subtype in this series. This study aims to present a single institutional experience of these rare cysts and compare their features with those found in the review of existing literature on ACLO and AL. Overall, thirteen cases of adrenal cysts were diagnosed and surgically excised during the study period, onto which we performed immunohistochemistry using a panel of antibodies (CD31, CD34, Pan Cytokeratin AE-1/AE-3, Factor VII, D2-40, and ERG). Four cases of ACLO and two AL were found. The lesions predominantly affected right adrenal, and the majority of patients were middle-age females, of Caucasian ethnicity, and asymptomatic. In our literature review, we found 108 cases of ACLO/AL from 57 articles with similar sex and age distribution. The diagnosis and subclassification of adrenal cysts are challenging, and there is a significant overlapping between the definition of ACLO and AL.

Magnetic resonance imaging and previous cesarean section in placenta accrete spectrum disorder: Predictor model

Abstract Objective To evaluate objective criteria of Magnetic Resonance Imaging (MRI) of Placenta Accreta Spectrum disorder (PAS) analyzing interobserver agreement and to derive a model including imaging and clinical variables to predict PAS. Methods A retrospective review including patients submitted to MRI with suspicious findings of PAS on ultrasound. Exclusion criteria were lack of pathology or surgical information and missing or poor-quality MRI. Two radiologists analyzed six MRI features, and significant clinical data were also recorded. PAS confirmed on pathology or during intraoperative findings were considered positive for the primary outcome. Variables were tested through logistic regression models. Results Final study included 96 patients with a mean age of 33 years and 73.0% of previous C-sections. All MRI features were significantly associated with PAS for both readers. After logistic regression fit, including MRI signs with a moderate or higher interobserver agreement, intraplacental T2 dark band was the most significant radiologic criteria, and ROC analysis resulted in an AUC = 0.782. After including the most relevant clinical data (previous C-section) to the model, the ROC analysis improved to an AUC = 0.893. Conclusion Simplified objective criteria on MRI, including intraplacental T2 dark band associated with clinical information of previous C-sections, had the highest accuracy and was used for a predictive model of PAS.

Which criteria can be used to predict benignity in solid renal lesions lower-equal to 2 cm?

PURPOSE: To evaluate magnetic resonance imaging (MRI) criteria of solid renal lesions lower-equal to 2 cm to differentiate benign and malignant tumors, using histopathology as gold standard. METHODS: Three radiologists independently evaluated objective and subjective MRI criteria of focal renal lesions. A total of 105 nodules of patients who had MRI and histopathological results in our institution were included. Subjective criteria evaluated were signal on T2-weighted imaging, presence of microscopic and macroscopic fat, hemosiderin, hemorrhage, central scar, segmented inversion enhancement and enhancement type; objective criteria were gender, ADC value, heterogeneity on T2-weighted imaging and proportion of enhancement in late post-contrast phases. Finally, the readers classified the lesions in probably benign or malignant. Interobserver agreement was evaluated by the Gwet method, and the quantitative variables by intraclass correlation coefficients. To adjust the predictive model, the logistic regression model was used considering the benignity variable as outcome. RESULTS: A total of 26 nodules (24.5%) were benign and 79 (75.2%) were malignant, with size ranging from 7 to 20 mm (median: 14 mm). The most frequent subtype was papillary renal cell carcinoma (RCC) (35.2%), followed by clear-cell RCC (24.8%) and oncocytoma (12.4%). The univariate and multivariate analysis showed, among all categories evaluated, that microscopic fat (p: 0.072), intermediate (p: 0.004) and hyper-enhancement (p: 0.031) and female sex (p: 0.0047) had the best outcome for benignity, within odds ratios of 4.29, 5.75, 4.07 and 2.86, respectively. CONCLUSION: In small solid renal lesions lower-equal to 2 cm, microscopic fat, moderate and hyper-enhancement and female sex were associated with benignity.

The effect of sirolimus on angiomyolipoma is determined by decrease of fat-poor compartments and includes striking reduction of vascular structures.

Renal angiomyolipomas hemorrhage is associated with their size and vascular constitution. The effects of sirolimus on different components of angiomyolipomas was analyzed in patients with tuberous sclerosis complex, sporadic lymphangioleiomyomatosis and multiple sporadic angiomyolipomas. Thirty angiomyolipomas from 14 patients treated with sirolimus were retrospectively evaluated. A Hounsfield-unit threshold was used to classify angiomyolipomas in fat-rich, fat-poor and intermediate-fat tumors, and to categorize tumor compartments in fat rich, fat poor, intermediate fat and highly vascularized. Diameter variations were measured to assess the effects on aneurysmatic/ectatic vascular formations. Volume reduction following treatment with sirolimus was higher in fat-poor than fat-rich angiomyolipomas. Tumor reduction was mainly determined by decrease of the fat-poor and highly-vascularized compartments while the volume of the fat-rich compartment increased. Broad liposubstitution was observed in some tumors. A median reduction of 100% (75 to 100) in the diameter of aneurysmatic/ectatic vascular structures was observed. Our study showed that sirolimus reduces the size of angiomyolipomas by decreasing primarily their highly-vascularized and fat-poor compartments. This effect is associated with a remarkable reduction of tumoral aneurysms/ectatic vessels, revealing the likely mechanism responsible for the risk-decreasing effect of mTOR inhibitors on angiomyolipoma bleeding. These findings support the role of mTOR in the development of angiomyolipoma blood vessels.

Prevalence, growth rate and complications of splenic artery aneurysms in chronic liver disease patients.

Background: Chronic liver disease (CLD) patients are at greater risk for developing splenic artery aneurysm (SAA). Treatment for aneurysms > 2.5 cm in this population is considered. However, the procedure might be challenging in CLD patients, and complications may interfere in liver transplantation. We, therefore, sought to estimate the prevalence, growth rate and complications of SAA in patients with CLD. As secondary objective, we sought to evaluate whether those features differ in pre and post transplantation follow-up and among aneurysms with diameters greater or less than 2.5 cm at diagnosis. Patients and methods: We searched for the terms "SAA" and "CLD" on CT or MRI reports from January 2009 to December 2016. Patients with single examination or less than 6 months follow-up were excluded. Results: Fifty nine out of 2050 CLD patients presented SAA (prevalence of 2.9%). Fifteen patients were excluded (due to exclusion criteria). Forty-four CLD patients (mean age 55.9 years) presented 76 SAA (follow-up median of 27.2 months). Aneurysms presented mean size of 1.5 ± 0.74 cm at diagnosis and growth rate of 0.12 ± 0.14 cm/y. Two (4.5%) patients presented mild complications (aneurysm thrombosis). No significant differences were observed in the growth rates of aneurysms < 2.5 cm and ≥ 2.5 cm or in the initial size and growth rates of aneurysms of patients submitted to and not submitted to liver transplantation. Conclusions: The estimated prevalence of SAA in patients with DLC in the Brazilian population is 2.9% (CI95% 2.2-3.6%). Although SAA in CLD patients are less likely to remain stable and grow faster than in general population, aneurysms are usually diagnosed at smaller size and complications are rare. These findings might support conservative management with close surveillance, especially in smaller aneurysms.

A comparative study of ultrasound and cross-sectional imaging for detection of small renal masses: anatomic factors and radiologist's experience.

OBJECTIVE: To evaluate anatomic factors and radiologist's experience in the detection of solid renal masses on ultrasonography. METHODS: We searched for solid renal masses diagnosed on cross-sectional imaging from 2007 to 2017 that also had previous ultrasonography from the past 6 months. The following features were evaluated: nodule size, laterality, location and growth pattern, patient body mass index and radiologist's experience in ultrasound. In surgically resected cases, pathologic reports were evaluated. Unpaired t test and χ2 test were used to evaluate differences among subgroups, using R-statistics. Statistical significance was set at p<0.05. RESULTS: The initial search of renal nodules on cross-sectional imaging resulted in 428 lesions and 266 lesions were excluded. Final cohort included 162 lesions and, of those, 108 (67%) were correctly detected on ultrasonography (Group 1) and 54 (33%) were missed (Group 2). Comparison of Groups 1 and 2 were as follows, respectively: body mass index (27.7 versus 27.1; p=0.496), size (2.58cm versus 1.74cm; p=0.003), laterality (54% versus 59% right sided; p=0.832), location (27% versus 22% upper pole; p=0.869), growth pattern (25% versus 28% endophytic; p=0.131) and radiologist's experience (p=0.300). From surgically resected cases, histology available for Group 1 was clear cell (n=11), papillary (n=15), chromophobe (n=2) renal cell carcinoma, oncocytoma (n=1), and, for Group 2, clear cell (n=7), papillary (n=5) renal cell carcinoma, oncocytoma (n=2), angiomyolipoma, chromophobe renal cell carcinoma, and interstitial pyelonephritis (n=1, each). CONCLUSION: Size was the only significant parameter related to renal nodule detection on ultrasound.

Can multiparametric magnetic resonance of the prostate avoid biopsies in patients with elevated PSA and surgical indication for benign prostatic enlargement?

INTRODUCTION: To evaluate the clinical dilemma of men with surgical indication due to benign prostatic enlargement (BPE) and concomitant elevated PSA, we analysed if multiparametric magnetic resonance imaging (mpMRI) could safely prescind the prostate biopsy. METHODS: Forty men with surgical indication due to BPE and concomitantly elevated PSA levels were prospectively enrolled and retrospectively analysed. All patients underwent 1.5 Tesla mpMRI prior to TRUS-guided biopsies. In cases where mpMRI was PIRADS 3 with focal lesions, PIRADS 4 or PIRADS 5, additional fragments were obtained with the fusion guided technique. Biopsy histopathological results were used as the standard of reference. Two scenarios were evaluated: scenario 1, considering mpMRI PIRADS 1 and 2 as negative; and scenario 2, considering PIRADS 1, 2 and 3 as negative. Clinically significant prostate cancer (CsPCa) was defined as ISUP ≥ 2. RESULTS: Median age was 68 years, median PSA was 9.41 (6.40-19.54) and median prostatic volume was 116.5 cc (IQR 86.5-155). Scenario 1 mpMRI sensitivity, specificity, PPV, NPV and accuracy for any prostate cancer on prostate biopsy was 76.9%, 63%, 50%, 85% and 67.5%. For csPCa, they were 87.5%, 59.4%, 35%, 95% and 65%, respectively, for the same measures. Scenario 2 the sensitivity, specificity, PPV, NPV and accuracy of mpMRI for any prostate cancer on prostate biopsy was 53.8%, 96.3%, 87.5%, 81.3% and 82.5%. For csPCa, they were 75%, 93.8%, 75%, 93.8% and 90%, respectively, for the same measures. CONCLUSION: Prostate mpMRI may prevent unnecessary biopsies in patients with elevated PSA and surgical indications due to BPE, given its high negative predictive value.

A comparative study of ultrasound and cross-sectional imaging for detection of small renal masses: anatomic factors and radiologists experience / Estudo comparativo de ultrassonografia e métodos seccionais para detecção de pequenas lesões renais: fatores anatômicos e experiência do radiologista

ABSTRACT Objective: To evaluate anatomic factors and radiologist's experience in the detection of solid renal masses on ultrasonography. Methods: We searched for solid renal masses diagnosed on cross-sectional imaging from 2007 to 2017 that also had previous ultrasonography from the past 6 months. The following features were evaluated: nodule size, laterality, location and growth pattern, patient body mass index and radiologist's experience in ultrasound. In surgically resected cases, pathologic reports were evaluated. Unpaired t test and χ2 test were used to evaluate differences among subgroups, using R-statistics. Statistical significance was set at p<0.05. Results: The initial search of renal nodules on cross-sectional imaging resulted in 428 lesions and 266 lesions were excluded. Final cohort included 162 lesions and, of those, 108 (67%) were correctly detected on ultrasonography (Group 1) and 54 (33%) were missed (Group 2). Comparison of Groups 1 and 2 were as follows, respectively: body mass index (27.7 versus 27.1; p=0.496), size (2.58cm versus 1.74cm; p=0.003), laterality (54% versus 59% right sided; p=0.832), location (27% versus 22% upper pole; p=0.869), growth pattern (25% versus 28% endophytic; p=0.131) and radiologist's experience (p=0.300). From surgically resected cases, histology available for Group 1 was clear cell (n=11), papillary (n=15), chromophobe (n=2) renal cell carcinoma, oncocytoma (n=1), and, for Group 2, clear cell (n=7), papillary (n=5) renal cell carcinoma, oncocytoma (n=2), angiomyolipoma, chromophobe renal cell carcinoma, and interstitial pyelonephritis (n=1, each). Conclusion: Size was the only significant parameter related to renal nodule detection on ultrasound.

RESUMO Objetivo: Avaliar os fatores anatômicos e a experiência do radiologista na detecção de massas renais sólidas na ultrassonografia. Métodos: Buscamos massas renais sólidas diagnosticadas em imagens seccionais, de 2007 a 2017, que também tivessem ultrassonografia prévia nos últimos 6 meses. As seguintes características foram avaliadas: tamanho do nódulo, lateralidade, localização e padrão de crescimento, índice de massa corporal do paciente e experiência do radiologista em ultrassonografia. Nos casos com ressecção cirúrgica, os laudos de patologia foram analisados. O teste t não pareado e o teste χ2 foram utilizados para avaliar as diferenças entre os subgrupos, usando R-statistics. A significância estatística foi estabelecida em p<0,05. Resultados: A pesquisa inicial de nódulos renais achados em imagens seccionais resultou em 428 lesões, com 266 exclusões. A coorte final incluiu 162 lesões e, destas, 108 (67%) foram detectadas corretamente na ultrassonografia (Grupo 1), e 54 (33%) não foram identificadas (Grupo 2). A comparação dos Grupos 1 e 2 mostrou índice de massa corporal (27,7 versus 27,1; p=0,496), tamanho (2,58cm versus 1,74cm; p=0,003), lateralidade (54% versus 59% no lado direito; p=0,832), localização (27% versus 22% no polo superior; p=0,869), padrão de crescimento (25% versus 28% endofítico; p=0,131) e experiência do radiologista (p=0,300). A histologia disponível para o Grupo 1 foi carcinoma renal de células claras (n=11), papilar (n=15), cromófobo (n=2), oncocitoma (n=1), e, para o Grupo 2, carcinoma renal de células claras (n=7), papilar (n=5), oncocitoma (n=2), angiomiolipoma, cromófobo e pielonefrite intersticial (n=1, cada). Conclusão: O tamanho foi o único parâmetro significativo relacionado à detecção de nódulos renais no ultrassom.

Morphologic criteria of vermiform appendix on computed tomography and a possible risk of developing acute appendicitis.

OBJECTIVE: To evaluate the correlation of morphological criteria of the cecal appendix using computed tomography (CT) and the possible risk of developing acute appendicitis. MATERIALS AND METHODS: Cases were defined as patients with surgically confirmed acute appendicitis who had undergone CT at least twice: at diagnosis and at least one month prior. Controls were defined as emergency patients with abdominal pain who had undergone abdominal CT that excluded acute appendicitis and had also undergone CT at least one month before. RESULTS: 100 cases and 100 controls were selected for inclusion in the final analysis. Comparisons between the cases and controls revealed the following: mean transverse diameter of 0.6 cm (range, 0.4-1.0 cm) versus 0.6 cm (range, 0.6-0.8 cm; p = 0.37); mean length of 6.6 cm (range, 3.5-9.7 cm) versus 6.6 cm (range, 4.5-8.3 cm; p = 0.87); mean angle of 100° (range, 23-178°) versus 86° (range, 43-160°; p = 0.01); vertical descending orientation in 56% versus 45% (p = 0.2); absence of gas in 69% versus 77% (p = 0.34); and presence of an appendicolith in 17% versus 8% (p = 0.08). CONCLUSION: Hypothetical risk factors for obstruction of the vermiform appendix detected on CT were not associated with acute appendicitis. That suggests that factors other than those related to mechanical obstruction are implicated in the pathogenesis of acute appendicitis.

OBJETIVO: Avaliar a correlação de critérios morfológicos do apêndice cecal por tomografia computadorizada (TC) e o risco de apendicite aguda. MATERIAIS E MÉTODOS: Casos foram definidos como apendicite aguda confirmada cirurgicamente que tiveram pelo menos dois exames de TC: um no diagnóstico de apendicite aguda e outro no mínimo um mês antes. O grupo controle foi definido como pacientes emergenciais com dor abdominal com TC de abdome excluindo apendicite aguda e com TC prévia pelo menos um mês antes. RESULTADOS: 100 casos e 100 controles foram selecionados. A comparação das variáveis dos casos e controles revelou: diâmetro transverso médio de 0,6 cm (faixa: 0,4-1,0 cm) versus 0,6 (faixa: 0,6-0,8 cm) (p = 0,37); comprimento médio de 6,6 cm (faixa: 3,5-9,7 cm) versus 6,6 cm (faixa: 4,5-8,3 cm) (p = 0,87); ângulo médio de 100° (faixa: 23-178°) versus 86° (faixa: 43-160°) (p = 0,01); orientação descendente em 56% versus 45% (p = 0,2); ausência de gás em 69% versus 77% (p = 0,34) e presença de apendicólito em 17% versus 8% (p = 0,08). CONCLUSÃO: Fatores obstrutivos hipotéticos do apêndice cecal na TC não foram associados a apendicite aguda. Isso sugere que outros fatores diferentes de obstrução mecânica podem estar implicados na gênese da apendicite aguda.

Common pitfalls in renal mass evaluation: a practical guide.

More than half of patients over 50 years of age have had at least one focal renal lesion detected as an incidental finding during an ultrasound, computed tomography, or magnetic resonance imaging examination. Although the majority of such lesions can be easily detected and correctly characterized, misdiagnoses may occur and are often related to methodological limitations, inappropriate imaging protocols, or misinterpretation. This pictorial essay provides recommendations on how to recognize benign and malignant renal processes that can be potentially missed or mischaracterized in imaging studies.

Mais da metade dos pacientes com mais de 50 anos de idade pode ter pelo menos uma lesão renal focal detectada de modo incidental em estudos de imagem, como ultrassonografia, tomografia computadorizada ou ressonância magnética. Embora a maioria dessas lesões possa ser facilmente caracterizada, erros de diagnóstico podem ocorrer e geralmente estão relacionados a limitações de métodos, protocolos de imagem inadequados e interpretação incorreta. Este ensaio iconográfico aborda recomendações sobre como reconhecer e interpretar lesões focais renais em estudos de imagem.

Common pitfalls in renal mass evaluation: a practical guide / Armadilhas comuns na avaliação da massa renal: um guia prático

Abstract More than half of patients over 50 years of age have had at least one focal renal lesion detected as an incidental finding during an ultrasound, computed tomography, or magnetic resonance imaging examination. Although the majority of such lesions can be easily detected and correctly characterized, misdiagnoses may occur and are often related to methodological limitations, inappropriate imaging protocols, or misinterpretation. This pictorial essay provides recommendations on how to recognize benign and malignant renal processes that can be potentially missed or mischaracterized in imaging studies.

Resumo Mais da metade dos pacientes com mais de 50 anos de idade pode ter pelo menos uma lesão renal focal detectada de modo incidental em estudos de imagem, como ultrassonografia, tomografia computadorizada ou ressonância magnética. Embora a maioria dessas lesões possa ser facilmente caracterizada, erros de diagnóstico podem ocorrer e geralmente estão relacionados a limitações de métodos, protocolos de imagem inadequados e interpretação incorreta. Este ensaio iconográfico aborda recomendações sobre como reconhecer e interpretar lesões focais renais em estudos de imagem.

Morphologic criteria of vermiform appendix on computed tomography and a possible risk of developing acute appendicitis / Critérios morfológicos do apêndice cecal na tomografia computadorizada e possível risco de desenvolver apendicite aguda

Abstract Objective: To evaluate the correlation of morphological criteria of the cecal appendix using computed tomography (CT) and the possible risk of developing acute appendicitis. Materials and Methods: Cases were defined as patients with surgically confirmed acute appendicitis who had undergone CT at least twice: at diagnosis and at least one month prior. Controls were defined as emergency patients with abdominal pain who had undergone abdominal CT that excluded acute appendicitis and had also undergone CT at least one month before. Results: 100 cases and 100 controls were selected for inclusion in the final analysis. Comparisons between the cases and controls revealed the following: mean transverse diameter of 0.6 cm (range, 0.4-1.0 cm) versus 0.6 cm (range, 0.6-0.8 cm; p = 0.37); mean length of 6.6 cm (range, 3.5-9.7 cm) versus 6.6 cm (range, 4.5-8.3 cm; p = 0.87); mean angle of 100° (range, 23-178°) versus 86° (range, 43-160°; p = 0.01); vertical descending orientation in 56% versus 45% (p = 0.2); absence of gas in 69% versus 77% (p = 0.34); and presence of an appendicolith in 17% versus 8% (p = 0.08). Conclusion: Hypothetical risk factors for obstruction of the vermiform appendix detected on CT were not associated with acute appendicitis. That suggests that factors other than those related to mechanical obstruction are implicated in the pathogenesis of acute appendicitis.

Resumo Objetivo: Avaliar a correlação de critérios morfológicos do apêndice cecal por tomografia computadorizada (TC) e o risco de apendicite aguda. Materiais e Métodos: Casos foram definidos como apendicite aguda confirmada cirurgicamente que tiveram pelo menos dois exames de TC: um no diagnóstico de apendicite aguda e outro no mínimo um mês antes. O grupo controle foi definido como pacientes emergenciais com dor abdominal com TC de abdome excluindo apendicite aguda e com TC prévia pelo menos um mês antes. Resultados: 100 casos e 100 controles foram selecionados. A comparação das variáveis dos casos e controles revelou: diâmetro transverso médio de 0,6 cm (faixa: 0,4-1,0 cm) versus 0,6 (faixa: 0,6-0,8 cm) (p = 0,37); comprimento médio de 6,6 cm (faixa: 3,5-9,7 cm) versus 6,6 cm (faixa: 4,5-8,3 cm) (p = 0,87); ângulo médio de 100° (faixa: 23-178°) versus 86° (faixa: 43-160°) (p = 0,01); orientação descendente em 56% versus 45% (p = 0,2); ausência de gás em 69% versus 77% (p = 0,34) e presença de apendicólito em 17% versus 8% (p = 0,08). Conclusão: Fatores obstrutivos hipotéticos do apêndice cecal na TC não foram associados a apendicite aguda. Isso sugere que outros fatores diferentes de obstrução mecânica podem estar implicados na gênese da apendicite aguda.

Comparative study between monoexponential and biexponential diffusion weighted imaging sequences in multiparametric prostate magnetic resonance imaging.

OBJECTIVE: To compare qualitatively and quantitatively, in terms of image quality, a new biexponential diffusion sequence protocol with the standard monoexponential diffusion protocol on multiparametric prostate magnetic resonance imaging. METHODS: This study had a prospective data collection and cross-sectional analysis. Between August and November 2017, a total of 70 patients who underwent multiparametric prostate magnetic resonance imaging due to clinical suspicion of prostatic neoplasia were recruited. The images obtained were evaluated by two independent readers regarding subjective/qualitative criteria (six criteria) and objective/quantitative criteria (three criteria), always comparing the monoexponential to biexponential acquisition protocols. The results were compared by statistical analysis (interobserver agreement - Gwet coefficient; analysis of the qualitative variables - Stuart-Maxwell test; and analysis of the quantitative variables - Wilcoxon test). RESULTS: After exclusion of four patients, the final sample consisted of 66 patients. A good/excellent inter observer agreement was stablished for subjective criteria (except in one criteria). For the qualitative analysis the amount of good or excellent evaluations was higher for the monoexponential protocol (except in one category), with evidence of significant differences for three criteria (diffusion weighted imaging global quality; diffusion weighted imaging signal-to-noise ratio; and apparent diffusion coefficient signal-to-noise ratio). For the quantitative data analysis, the monoexponential protocol showed less variability of the anteroposterior diameters, meaning less distortion of the images, and better estimated signal-to-noise ratio. CONCLUSION: In our data, the quality of the images of the monoexponential standard diffusion sequence was qualitatively and quantitatively superior to those of the biexponential diffusion weighted imaging sequence.

Progression rate in Bosniak category IIF complex renal cysts.

OBJECTIVE: To evaluate progression rate of Bosniak category IIF complex renal cysts and the malignancy rate among surgically resected cysts. MATERIALS AND METHODS: We performed a database search for complex renal cysts classified as Bosniak category IIF on computed tomography or magnetic resonance imaging between January 2008 and April 2016. Follow-up examinations (computed tomography or magnetic resonance imaging) were used in order to evaluate progression (Bosniak category reclassification) and stability, the latter being defined as remaining stable for a minimum of six months. Pathology reports were used as the reference to assess the malignancy rate of surgically resected cysts. RESULTS: A total of 152 cysts in 143 patients were included in the final analysis. Seven cysts (4.6%) were reclassified on follow-up studies, and mean time to progression was 20 months (range, 1 month to 4 years). Three cysts were surgically resected. All three were diagnosed as low-grade malignant renal cell carcinomas (RCCs): one clear cell RCC and two papillary RCCs. The remaining 145 cysts remained unchanged after a mean follow-up period of 28 months (range, 6 to 118 months). CONCLUSION: The progression rate in Bosniak category IIF cysts was low. Even lesions that were upgraded on follow-up remained stable, indicating an indolent behavior. Our data support the idea of conservative management of Bosniak IIF renal cyst.

OBJETIVO: Avaliar a taxa de progressão das lesões císticas renais complexas Bosniak II-F e a taxa de neoplasia maligna nas lesões ressecadas cirurgicamente. MATERIAIS E MÉTODOS: Realizamos uma pesquisa no banco de dados da nossa instituição reunindo lesões císticas renais complexas classificadas como Bosniak II-F em exames de tomografia computadorizada ou ressonância magnética, de janeiro de 2008 a abril de 2016. Foram utilizados exames de acompanhamento (tomografia computadorizada ou ressonância magnética) para avaliar a progressão na categoria Bosniak, com um mínimo de seis meses de estabilidade. Os relatórios de patologia foram utilizados como referência para avaliar a taxa de neoplasia maligna de lesões ressecadas cirurgicamente. RESULTADOS: Um total de 152 lesões em 143 pacientes foi incluído na análise final. Sete lesões foram reclassificadas em estudos de acompanhamento (4,6%) e o tempo médio de progressão foi de 20 meses (1 mês a 4 anos). Três pacientes tiveram cistos ressecados cirurgicamente, todos diagnosticados como carcinoma de células renais: um do subtipo células claras e dois papilíferos, todos de baixo grau. As 145 lesões restantes permaneceram inalteradas, com seguimento médio de 28 meses (6 a 118 meses). CONCLUSÃO: A taxa de progressão nos cistos categoria Bosniak II-F foi baixa. Mesmo as lesões que tiveram upgrade da categoria de Bosniak no seguimento permaneceram estáveis, indicando um comportamento indolente. Nossos dados apoiam a ideia de tratamento conservador do cisto renal Bosniak II-F.

Progression rate in Bosniak category IIF complex renal cysts / Taxa de progressão de lesões císticas renais complexas Bosniak II-F

Abstract Objective: To evaluate progression rate of Bosniak category IIF complex renal cysts and the malignancy rate among surgically resected cysts. Materials and Methods: We performed a database search for complex renal cysts classified as Bosniak category IIF on computed tomography or magnetic resonance imaging between January 2008 and April 2016. Follow-up examinations (computed tomography or magnetic resonance imaging) were used in order to evaluate progression (Bosniak category reclassification) and stability, the latter being defined as remaining stable for a minimum of six months. Pathology reports were used as the reference to assess the malignancy rate of surgically resected cysts. Results: A total of 152 cysts in 143 patients were included in the final analysis. Seven cysts (4.6%) were reclassified on follow-up studies, and mean time to progression was 20 months (range, 1 month to 4 years). Three cysts were surgically resected. All three were diagnosed as low-grade malignant renal cell carcinomas (RCCs): one clear cell RCC and two papillary RCCs. The remaining 145 cysts remained unchanged after a mean follow-up period of 28 months (range, 6 to 118 months). Conclusion: The progression rate in Bosniak category IIF cysts was low. Even lesions that were upgraded on follow-up remained stable, indicating an indolent behavior. Our data support the idea of conservative management of Bosniak IIF renal cyst.

Resumo Objetivo: Avaliar a taxa de progressão das lesões císticas renais complexas Bosniak II-F e a taxa de neoplasia maligna nas lesões ressecadas cirurgicamente. Materiais e Métodos: Realizamos uma pesquisa no banco de dados da nossa instituição reunindo lesões císticas renais complexas classificadas como Bosniak II-F em exames de tomografia computadorizada ou ressonância magnética, de janeiro de 2008 a abril de 2016. Foram utilizados exames de acompanhamento (tomografia computadorizada ou ressonância magnética) para avaliar a progressão na categoria Bosniak, com um mínimo de seis meses de estabilidade. Os relatórios de patologia foram utilizados como referência para avaliar a taxa de neoplasia maligna de lesões ressecadas cirurgicamente. Resultados: Um total de 152 lesões em 143 pacientes foi incluído na análise final. Sete lesões foram reclassificadas em estudos de acompanhamento (4,6%) e o tempo médio de progressão foi de 20 meses (1 mês a 4 anos). Três pacientes tiveram cistos ressecados cirurgicamente, todos diagnosticados como carcinoma de células renais: um do subtipo células claras e dois papilíferos, todos de baixo grau. As 145 lesões restantes permaneceram inalteradas, com seguimento médio de 28 meses (6 a 118 meses). Conclusão: A taxa de progressão nos cistos categoria Bosniak II-F foi baixa. Mesmo as lesões que tiveram upgrade da categoria de Bosniak no seguimento permaneceram estáveis, indicando um comportamento indolente. Nossos dados apoiam a ideia de tratamento conservador do cisto renal Bosniak II-F.