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The current study aimed to evaluate the accuracy of diffusion­weighted imaging and morphological aspects at 3 Tesla (T) and 1.5T MRI for diagnosing metastatic lymph nodes (LN) in cervical cancer. A retrospective study was conducted at the Barretos Cancer Hospital. A total of 45 patients with cervical cancer who underwent MRI examination and pelvic and/or para­aortic lymphadenectomy as part of surgical procedure were included. Data regarding LN images included size (short­axis diameters), morphology (usual, rounded or amorphous), appearance (homogeneous or heterogeneous), limits (regular, irregular or imprecise), presence or absence of necrosis, diffusion (normal or greater restriction than expected for normal tissue) and aspect (suspected, undetermined or normal). These findings were compared with histopathological results. According to histology results, among the 45 patients, 14 (31.1%) LNs were tested positive for metastasis and 31 (68.9%) LNs were tested negative. A total of 41 metastatic positive LNs were detected from a total of 976 resected nodes. Twelve patients from the 45 (26.7%) had LN classified as metastatic by histology and suspected by MRI, 26 (57.8%) as negative in both evaluations, 2 (4.4%) as positive by histology and negative by MRI and five (11.1%) as negative by histology and positive by MRI. Based on these results, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were 85.7, 83.9, 70.6, 92.9 and 84.4%, respectively. The Cohen's κ test exposed a general outcome of 0.657 (P<0.05), demonstrating that the two variables (histology and MRI) have substantial concordance. The κ test results between histological and MRI data for paraaortic and pelvic LNs were found to be 1 and 0.657, respectively. Finally, short axis >10 mm, T2 hypointensity, rounded morphology and greater restriction than expected for normal tissues are the four most common MRI findings associated with metastatic LN. The concordance between MRI and histology was substantial, indicating that this method using MRI for diagnosing suspected LN metastasis is reliable. The results of the current study revealed that the most important aspects to be evaluated in MRI include: Short axis >10 mm, T2 hypointensity, rounded morphology and greater restriction than expected for normal tissues. If these four characteristics are present in MRI, histological evaluation is likely to reveal positive lymph node metastasis.

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In this work we model the noise properties of a computed radiography (CR) mammography system by adding an extra degree of freedom to a well-established noise model, and derive a variance-stabilizing transform (VST) to convert the signal-dependent noise into approximately signal-independent. The proposed model relies on a quadratic variance function, which considers fixed-pattern (structural), quantum and electronic noise. It also accounts for the spatial-dependency of the noise by assuming a space-variant quantum coefficient. The proposed noise model was compared against two alternative models commonly found in the literature. The first alternative model ignores the spatial-variability of the quantum noise, and the second model assumes negligible structural noise. We also derive a VST to convert noisy observations contaminated by the proposed noise model into observations with approximately Gaussian noise and constant variance equals to one. Finally, we estimated a look-up table that can be used as an inverse transform in denoising applications. A phantom study was conducted to validate the noise model, VST and inverse VST. The results show that the space-variant signal-dependent quadratic noise model is appropriate to describe noise in this CR mammography system (errors< 2.0% in terms of signal-to-noise ratio). The two alternative noise models were outperformed by the proposed model (errors as high as 14.7% and 9.4%). The designed VST was able to stabilize the noise so that it has variance approximately equal to one (errors< 4.1%), while the two alternative models achieved errors as high as 26.9% and 18.0%, respectively. Finally, the proposed inverse transform was capable of returning the signal to the original signal range with virtually no bias.

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OBJECTIVE: To evaluate the difference between early and delayed removal of indwelling urinary catheter after radical hysterectomy (RH) or radical trachelectomy (RT). METHODS: An ambispective study was conducted in early-stage cervical cancer patients who underwent RH or RT. Delayed indwelling urinary catheter removal occurred on a postoperative day (POD) 7 in the retrospective group (January 2012-November 2013), and early removal occurred on POD 1 in the prospective group (May 2014-June 2017). The postvoid residual (PVR) test was performed after indwelling catheter removal in both groups. RESULTS: Our sample included 47 patients in the delayed group and 48 in the early one. There was no difference in age, body mass index, tumor size, histology, stage, surgical approach, and intraoperative and postoperative complications. Indwelling urinary catheter reinsertion was needed in 16 (34%) patients in the delayed group and 12 (25%) in the early group (P = .37), with no statistical difference between the median PVR volumes -82.5 and 45 mL (P = .06), respectively. Seven (14.9%) patients in the delayed group presented with 30-day urinary tract infection vs two (4.2%) in the early group (P = .09). CONCLUSIONS: Early indwelling urinary catheter removal, in regard to the rate of catheter reinsertion and PVR volume, does not differ from delayed removal.

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PURPOSE: To investigate the use of an affine-variance noise model, with correlated quantum noise and spatially dependent quantum gain, for the simulation of noise in virtual clinical trials (VCT) of digital breast tomosynthesis (DBT). METHODS: Two distinct technologies were considered: an amorphous-selenium (a-Se) detector with direct conversion and a thallium-doped cesium iodide (CsI(Tl)) detector with indirect conversion. A VCT framework was used to generate noise-free projections of a uniform three-dimensional simulated phantom, whose geometry and absorption match those of a polymethyl methacrylate (PMMA) uniform physical phantom. The noise model was then used to generate noisy observations from the simulated noise-free data, while two clinically available DBT units were used to acquire projections of the PMMA physical phantom. Real and simulated projections were then compared using the signal-to-noise ratio (SNR) and normalized noise power spectrum (NNPS). RESULTS: Simulated images reported errors smaller than 4.4% and 7.0% in terms of SNR and NNPS, respectively. These errors are within the expected variation between two clinical units of the same model. The errors increase to 65.8% if uncorrelated models are adopted for the simulation of systems featuring indirect detection. The assumption of spatially independent quantum gain generates errors of 11.2%. CONCLUSIONS: The investigated noise model can be used to accurately reproduce the noise found in clinical DBT. The assumption of uncorrelated noise may be adopted if the system features a direct detector with minimal pixel crosstalk.

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In countries where poliomyelitis has been eradicated, Guillain-Barré syndrome (GBS) is the leading cause of acute flaccid paralysis. The range of infections that precede GBS in Brazil is unknown. Campylobacter jejuni infection is the most frequent trigger of GBS worldwide. Given the lack of systematic surveillance of diarrheal diseases, particularly in adults, the incidence of enteritis caused by C. jejuni in developing countries is unknown. From 2014 to 2016, pretreatment serum samples from 63 GBS patients were tested by immunoglobulin M (IgM) enzyme-linked immunosorbent assay for C. jejuni. Campylobacter jejuni IgM antibodies were detected in 17% (11/63) of the samples. There was no association between serological positivity (IgM) for C. jejuni and the occurrence of diarrhea among the investigated cases (P = 0.36). Hygiene measures, basic sanitation, and precautions during handling and preparation of food of animal origin may help prevent acute flaccid paralysis.

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PURPOSE: This work proposes an accurate method for simulating dose reduction in digital mammography starting from a clinical image acquired with a standard dose. METHODS: The method developed in this work consists of scaling a mammogram acquired at the standard radiation dose and adding signal-dependent noise. The algorithm accounts for specific issues relevant in digital mammography images, such as anisotropic noise, spatial variations in pixel gain, and the effect of dose reduction on the detective quantum efficiency. The scaling process takes into account the linearity of the system and the offset of the detector elements. The inserted noise is obtained by acquiring images of a flat-field phantom at the standard radiation dose and at the simulated dose. Using the Anscombe transformation, a relationship is created between the calculated noise mask and the scaled image, resulting in a clinical mammogram with the same noise and gray level characteristics as an image acquired at the lower-radiation dose. RESULTS: The performance of the proposed algorithm was validated using real images acquired with an anthropomorphic breast phantom at four different doses, with five exposures for each dose and 256 nonoverlapping ROIs extracted from each image and with uniform images. The authors simulated lower-dose images and compared these with the real images. The authors evaluated the similarity between the normalized noise power spectrum (NNPS) and power spectrum (PS) of simulated images and real images acquired with the same dose. The maximum relative error was less than 2.5% for every ROI. The added noise was also evaluated by measuring the local variance in the real and simulated images. The relative average error for the local variance was smaller than 1%. CONCLUSIONS: A new method is proposed for simulating dose reduction in clinical mammograms. In this method, the dependency between image noise and image signal is addressed using a novel application of the Anscombe transformation. NNPS, PS, and local noise metrics confirm that this method is capable of precisely simulating various dose reductions.

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A Brazilian ranch worker with encephalitis and flaccid paralysis was evaluated in the regional Acute Encephalitis Syndromic Surveillance Program. This was the first Brazilian patient who met the Centers for Disease Control and Prevention (CDC) confirmation criteria for West Nile virus disease. Owing to the overlapping of neurological manifestations attributable to several viral infections of the central nervous system, this report exemplifies the importance of human acute encephalitis surveillance. The syndromic approach to human encephalitis cases may enable early detection of the introduction of unusual virus or endemic occurrence of potentially alarming diseases within a region.

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OBJECTIVES: Radical trachelectomy is considered standard of care in patients with early-stage cervical cancer interested in future fertility. The goal of this study was to compare operative, oncologic, and fertility outcomes in patients with early-stage cervical cancer undergoing open vs. minimally invasive radical trachelectomy. METHODS: A retrospective review was performed of patients from four institutions who underwent radical trachelectomy for early-stage cervical cancer from June 2002 to July 2013. Perioperative, oncologic, and fertility outcomes were compared between patients undergoing open vs. minimally invasive surgery. RESULTS: A total of 100 patients were included in the analysis. Fifty-eight patients underwent open radical trachelectomy and 42 patients underwent minimally invasive surgery (MIS=laparoscopic or robotic). There were no differences in patient age, body mass index, race, histology, lymph vascular space invasion, or stage between the two groups. The median surgical time for MIS was 272min [range, 130-441min] compared with 270min [range, 150-373min] for open surgery (p=0.78). Blood loss was significantly lower for MIS vs. laparotomy (50mL [range, 10-225mL] vs. 300mL [50-1100mL]) (p<0.0001). Nine patients required blood transfusion, all in the open surgery group (p=0.010). Length of hospitalization was shorter for MIS than for laparotomy (1day [1-3 days] vs. 4days [1-9 days]) (p<0.0001). Three intraoperative complications occurred (3%): 1 bladder injury, and 1 fallopian tube injury requiring unilateral salpingectomy in the MIS group and 1 vascular injury in the open surgery group. The median lymph node count was 17 (range, 5-47) for MIS vs. 22 (range, 7-48) for open surgery (p=0.03). There were no differences in the rate of postoperative complications (30% MIS vs. 31% open surgery). Among 83 patients who preserved their fertility (33 MIS vs. 50 open surgery), 34 (41%) patients attempted to get pregnant. Sixteen (47%) patients were able to do so (MIS: 2 vs. laparotomy: 14, p=0.01). The pregnancy rate was higher in the open surgery group when compared to the MIS group (51% vs. 28%, p=0.018). However, median follow-up was shorter is the MIS group compared with the open surgery group (25months [range, 10-69] vs. 66months [range, 11-147]). To date, there has been one recurrence in the laparotomy group and none in the MIS group. CONCLUSIONS: Our results suggest that radical trachelectomy via MIS results in less blood loss and a shorter hospital stay. Fertility rates appear higher in patients undergoing open radical trachelectomy.

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OBJECTIVE: To develop a prognostic model for women who underwent surgical treatment for cervical intraepithelial neoplasia. DESIGN: Cohort study. Patient inclusion and follow-up occurred retrospectively and prospectively. SETTING: Barretos Cancer Hospital, Barretos, São Paulo, Brazil. POPULATION: Women (n = 242) diagnosed with cervical intraepithelial neoplasia who were submitted to conization. METHODS: Immediately prior to surgical treatment, a cervical cytology sample was collected from each individual included in the study by endocervical brushing and stored in a preservative solution with methanol. A human papilloma virus-DNA test was conducted using an aliquot of the endocervical brushings. The surgical specimens were subjected to immunohistochemical analysis of p16 (immunohistochemical analysis 4a) protein expression. MAIN OUTCOME MEASURES: Two-year disease-free survival rates calculated for each study variable. Identified variables in the multivariate Cox model were used for elaboration of prognostic scores. RESULTS: Variables associated with outcome included age (p = 0.033), tobacco use (p < 0.001), final histopathological diagnosis (p = 0.007), surgical margins (p < 0.001), high-risk human papilloma virus status (p = 0.008), human papilloma virus-16 status (p < 0.001) and immunoexpression of p16 in the cytoplasm (p = 0.049). By the Cox model, independent risk factors for disease recurrence/persistence were: tobacco use (hazard risk = 3.0; 95% confidence interval 1.6-5.6), positive surgical margins (hazard risk = 3.2; 95% confidence interval 1.6-6.1), human papilloma virus-16 (hazard risk = 3.3; 95% confidence interval 1.6-6.9) and age over 45 years (hazard risk = 2.7; 95% confidence interval 1.1-6.6). CONCLUSIONS: Establishment of a prognostic score can represent a valuable tool for determining the risk of cervical intraepithelial neoplasia recurrence after conization. The use of clinical (age and tobacco use), pathological (surgical margins) and molecular (human papilloma virus-16 genotyping) factors can facilitate more appropriate patient follow up according to risk stratification.

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A new restoration methodology is proposed to enhance mammographic images through the improvement of contrast features and the simultaneous suppression of noise. Denoising is performed in the first step using the Anscombe transformation to convert the signal-dependent quantum noise into an approximately signal-independent Gaussian additive noise. In the Anscombe domain, noise is filtered through an adaptive Wiener filter, whose parameters are obtained by considering local image statistics. In the second step, a filter based on the modulation transfer function of the imaging system in the whole radiation field is applied for image enhancement. This methodology can be used as a preprocessing module for computer-aided detection (CAD) systems to improve the performance of breast cancer screening. A preliminary assessment of the restoration algorithm was performed using synthetic images with different levels of quantum noise. Afterward, we evaluated the effect of the preprocessing on the performance of a previously developed CAD system for clustered microcalcification detection in mammographic images. The results from the synthetic images showed an increase of up to 11.5 dB (p = 0.002) in the peak signal-to-noise ratio. Moreover, the mean structural similarity index increased up to 8.3 % (p < 0.001). Regarding CAD performance, the results suggested that the preprocessing increased the detectability of microcalcifications in mammographic images without increasing the false-positive rates. Receiver operating characteristic analysis revealed an average increase of 14.1 % (p = 0.01) in overall CAD performance when restored image sets were used.

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A Síndrome de Budd-chiari é caracterizada pela oclusão das veias supra-hepáticas e apresenta inúmeras causas, mas nenhuma delas é identificável em cerca de 60-70% dos pacientes. O diagnóstico é realizado pela suspeita clínica e confirmado por exames complementares, sendo a ultrassonografia com Doppler a mais sensível (85%). A terapia varia desde medicamentos, cirurgias como anastomoses portossistêmicos e transplante hepático até métodos menos invasivos como derivação intra-hepática portossistêmica transjugular (TIPS) e angioplastia. O objetivo desse trabalho é apresentar um paciente portador da SBC submetido à angioplastia transjugular da veia supra-hepática, utilizando via anterógrada (punção através da veia cava inferior trans-hepática, atingindo a veia supra-hepática e recanalizando anterogradamente a veia supra-hepática).

The Budd-chiari syndrome is characterized by occlusion of the supra-hepatic veins and has any causes, but none of them are identifiable by about 60-70% of patients. The diagnosis is made by clinical suspicion and confirmed by additional tests, and the Doppler ultrasound with the most sensitive (85%). The therapy varies from medications, surgeries such as liver transplantation and anastomosis portossistêmicos even less invasive methods like bypass intra-hepatic portosystemic transjugular (TIPS) and angioplasty. The aim of this article is to present a patient of SBC submitted to angioplasty transjugular the above hepatic vein using antegrade route (puncture through the inferior vena cava reaching the above-hepatic vein and the vein recanalizando anterograde above-liver).

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Pileflebite é uma complicação incomum das infecções intra-abdominais e está associada à alta mortalidade. A patogenia ainda não está esclarecida. O diagnóstico permanece difícil e frequentemente é tardio, uma vez que a clínica é inespecífica e é necessário um elevado grau de suspeição. Na maioria dos casos, o prognóstico é favorável. O fator mais importante é a precocidade no diagnóstico e a imediata antibioticoterapia específica. Relatamos um caso de um paciente com diagnóstico de pileflebite mesentérica secundária à diverticulite colônica.

Pylephlebitis is a uncommon complications of intraabdominalsuppuration and associated with high mortality. The pathogenic is not clear and diagnosis remains delay because of its nonspecific symptoms and is necessary high clinical suspicion. In the major of cases the prognostic is favorable. The most important determinants for the prognosis is earlydiagnosis and adequate medical. We report a case of patient with diagnosis of mesenteric Pylephlebitis secondary a colonic diverticulitis.

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JUSTIFICATIVA E OBJETIVOS: A paracoccidioidomicose é uma doença granulomatosa crônica causada por um fungo e acomete principalmente os pulmões e a pele. A clínica é variada e o envolvimento do sistema nervoso central (SNC) é raro. Quando não diagnosticada e tratada oportunamente pode levar às formas disseminadas graves e letais. O objetivo desse estudo foi demonstrar as características clínicas da rara apresentação dessa doença. RELATO DO CASO: Paciente do sexo masculino, 26 anos, imunocompetente, apresentava paracoccidiodomicose recidivante com envolvimento do SNC. CONCLUSÃO: Apesar de ser uma doença rara, deve-se ter em mente que a neuroparacoccidiodomicose pode atingir pacientes imunocompetentes. Portanto deve-se fazer o diagnóstico e o tratamento de forma precoce.

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JUSTIFICATIVA E OBJETIVOS: A doença de Weber Christianou paniculite lobular idiopática é uma doença rara, que se apresenta com inflamação recorrente da camada adiposa da pele. O objetivo deste estudo foi descrever o quadro clínico dessa doença e informar sobre sua presença e impacto na qualidade de vida dos pacientes. RELATO DO CASO: Paciente do sexo feminino, portadora dessa doença, que ficou 20 anos sem diagnóstico, mas quando se detectou sua presença foi possível a remissão. CONCLUSÃO: A importância do caso descrito está em demonstrar como a falta de diagnóstico interfere na qualidade devida dos pacientes, portanto é bom lembrar que doenças raras acontecem e seu diagnóstico só é feito quando se pensam em hipóteses e diagnósticos diferenciais, quesitos esses indispensáveis para o exercício da clínica médica.

BACKGROUND AND OBJECTIVES: Weber Christian disease or idiopathic lobular pannicullitis is a skin condition that features recurring inflammation in the fat layer of the skin. The aim of this article is to describe this rare pathology, the clinical findings and remember your presence and their impact on patient's quality of life. CASE REPORT: Female patient, we report a case of patient with Weber Christian disease that was undiagnosed for 20 years and, when it was done it was possible to remission of the disease. CONCLUSION: The importance of the case described is to demonstrate how the lack of diagnosis interfere with the quality of life of patients and we always remember that rare diseases occurand their diagnosis is only made when thinking about chance and differential diagnosis, these questions essential to the exercise of clinical practice.

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Tumores carcinóides têm origem nas células neuroendócrinas e foram descritos há cerca de cem anos por Lubarsch. Sua incidência gira em torno de 0,7 caso/100.000 habitantes. A localização pancreática é rara com incidência de 0,75% dos tumores carcinóides do trato digestivo. O objetivo desse trabalho é relatar caso de paciente portador de tumor carcinóide pancreático tratado através de ressecção tumoral por via laparoscópica.

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