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BACKGROUND: Typical propagation-based X-ray phase contrast imaging (PB-PCI) experiments using polyenergetic sources are tested in very ideal conditions: low-energy spectrum (mainly characteristic X-rays), small thickness and homogeneous materials considered weakly absorbing objects, large object-to-detector distance, long exposure times and non-clinical detector. OBJECTIVE: Explore PB-PCI features using boundary conditions imposed by a low power polychromatic X-ray source (X-ray spectrum without characteristic X-rays), thick and heterogenous materials and a small area imaging detector with high low-detection radiation threshold, elements commonly found in a clinical scenario. METHODS: A PB-PCI setup implemented using a microfocus X-ray source and a dental imaging detector was characterized in terms of different spectra and geometric parameters on the acquired images. Test phantoms containing fibers and homogeneous materials with close attenuation characteristics and animal bone and mixed soft tissues (bio-sample models) were analyzed. Contrast to Noise Ratio (CNR), system spatial resolution and Kerma values were obtained for all images. RESULTS: Phase contrast images showed CNR up to 15% higher than conventional contact images. Moreover, it is better seen when large magnifications (>3) and object-to-detector distances (>13 cm) were used. The influence of the spectrum was not appreciable due to the low efficiency of the detector (thin scintillator screen) at high energies. CONCLUSIONS: Despite the clinical boundary condition used in this work, regarding the X-ray spectrum, thick samples, and detection system, it was possible to acquire phase contrast images of biological samples.

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Introducción: el tratamiento de la malformación de Chiari I (MCI) y/o la siringomielia (SM) es controversial. La dinámica cuantitativa del LCR a nivel cráneo espinal es una alternativa que podría orientar la terapéutica. El objetivo de esta publicación es describir 5 casos en donde la utilización de la dinámica de LCR permitió guiar el tratamiento. Material y método: se revisaron las historias clínicas de 5 casos (edad media: 39 años / 3 mujeres y 2 varones). Todos fueron estudiados con RM en contraste de fase. El diagnóstico fue de MCI (1 caso) y SM (3 casos) o solo SM (1 caso). Sólo 2 casos con MCI+SM fueron intervenidos (descompresión + plástica dural). Todos fueron seguidos entre 1,5 y 6 años. Resultados: caso 1 (MCI) la velocidad del LCR fue normal por lo que su cefalea fue tratada médicamente con buenos resultados; caso 2 (MCI+SM) la velocidad estuvo aumentada por lo que fue intervenida controlándose los síntomas y la SM; caso 3 (MCI +SM) la velocidad fue normal siendo su diagnóstico compatible con síndrome post-siringomiélico; caso 4 (SM) la velocidad estuvo aumentada a nivel C5-C6 siendo su diagnóstico compatible con una SM espinal primaria; caso 5 (CMI + SM) luego de la intervención se observó que las velocidades y la SM tardaron 16 meses en normalizarse. Conclusión: en los casos descriptos la dinámica de LCR permitió realizar el diagnóstico correcto, determinar la conveniencia de realizar la cirugía, encontrar la causa y controlar la evolución postoperatoria(AU)

Background: the treatment of Chiari malformation I (CMI) and/or syringomyelia (SM) is controversial. The quantitative dynamics of CSF at the craniospinal level is an alternative that could guide therapy. The objective of this publication is to describe 5 cases in which the use of CSF dynamics allowed guiding the treatment. Methods: the medical records of 5 cases (mean age: 39 years / 3 women and 2 men) were reviewed. All were studied with MRI in phase contrast. The diagnosis was CMI (1 case) and SM (3 cases) or only SM (1 case). Only 2 cases with CMI+SM underwent surgery (decompression + duraplasty). All were followed between 1.5 and 6 years. Results: case 1 (CMI) the velocity of the CSF was normal, so his headache was treated medically with good results; case 2 (CMI+SM) the velocity was increased so it was intervened controlling the symptoms and the SM; case 3 (CMI +SM) the velocity was normal, its diagnosis being compatible with post-syringomyelic syndrome; case 4 (SM) the velocity was increased at the C5-C6 level, its diagnosis being compatible with a primary spinal SM; case 5 (CMI + SM) after the intervention it was observed that the velocities and the SM took 16 months to normalize. Conclusion: in the cases described, the CSF dynamics allowed the correct diagnosis to be made, to determine the advisability of performing surgery, to find the cause and to control the postoperative evolution(AU)

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BACKGROUND: In phase-contrast (PC) MRI, several dual velocity encoding methods have been proposed to robustly increase velocity-to-noise ratio (VNR), including a standard dual-VENC (SDV), an optimal dual-VENC (ODV), and bi- and triconditional methods. PURPOSE: To develop a correction method for the ODV approach and to perform a comparison between methods. STUDY TYPE: Case-control study. POPULATION: Twenty-six volunteers. FIELD STRENGTH/SEQUENCE: 1.5 T phase-contrast MRI with VENCs of 50, 75, and 150 cm/second. ASSESSMENT: Since we acquired single-VENC protocols, we used the background phase from high-VENC (VENCH ) to reconstruct the low-VENC (VENCL ) phase. We implemented and compared the unwrapping methods for different noise levels and also developed a correction of the ODV method. STATISTICAL TESTS: Shapiro-Wilk's normality test, two-way analysis of variance with homogeneity of variances was performed using Levene's test, and the significance level was adjusted by Tukey's multiple post hoc analysis with Bonferroni (P < 0.05). RESULTS: Statistical analysis revealed no extreme outliers, normally distributed residuals, and homogeneous variances. We found statistically significant interaction between noise levels and the unwrapping methods. This implies that the number of non-unwrapped pixels increased with the noise level. We found that for ß = VENCL /VENCH  = 1/2, unwrapping methods were more robust to noise. The post hoc test showed a significant difference between the ODV corrected and the other methods, offering the best results regarding the number of unwrapped pixels. DATA CONCLUSIONS: All methods performed similarly without noise, but the ODV corrected method was more robust to noise at the price of a higher computational time. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 1.

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Objectives.In cardiovascular magnetic resonance, the 3D time-resolved phase-contrast technique, also known as 4D flow, is gaining increasing attention due to applications that exploit three-directional velocity encoding throughout the cardiac cycle. Blood flow volume assessment usually requires an expert to draw regions of interest (ROI) around the vessel cross section, whereas the errors involved in this estimation have not been thoroughly investigated. Our objective is to quantify the influence of ROI sizing, angulation and spatial resolution of the reconstructed plane employed in blood flow measurements using 4D flow.Approach.Three circular ROIs were drawn around the ascending, arch and descending aorta of healthy volunteers (n= 27) and patients with a dilated ascending aorta or bicuspid valve (n= 37). We applied systematic changes of ROI diameter (up to ±10%), tilt angle (up to ±25°) and spatial resolution (from 0.25 to 2 mm) of the reconstructed oblique planes, calculating the effects on net, forward and backward blood flow volumes.Main results.Patients had a larger ascending aorta than healthy volunteers with similar ages and male sex proportion (60 ± 15 y.o. vs 58 ± 16 y.o. and 84% vs 70%, respectively). Higher forward and backward flow volumes were observed in the ascending aorta and the aortic arch of the patients with respect to controls (p< 0.001), whereas net volumes were similar: 74.0 ± 20.8 ml versus 75.7 ± 21.8 ml (p= 0.37), respectively. The ascending aorta was the most sensitive to ROI modifications. Changes of ±10% in the ROI diameter and ±25° in tilt angles produced flow volume differences of up to 9 ml (10%) and 18 ml (15%) in controls and patients, respectively. Modifying the reconstructed planes spatial resolution produced flow volume changes below 2 ml.Significance.Since the setting of the ROI size and plane angle could produce errors that represent up to 20% of the forward and/or backward aortic flow volume, a good standardization for vessel segmentation and plane positioning is desirable.

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Slice shear force (SSF) and laser diffraction, considered faster methodologies, for measuring beef instrumental tenderness and sarcomere length, were compared with reference methodologies Warner-Bratzler shear force (WBSF) and phase contrast microscopy. Striploin samples (n = 74) were analyzed for pH, sarcomere length, instrumental tenderness, myofibrillar fragmentation index, and sensorial tenderness. Pearson's correlation measured the association of meat evaluation methods with residual analysis of the multivariate analysis of variance model. The n-dimensional profile to evaluated methods was presented by biplot to identify the behavior of the correlation between the methods (variables). There was moderate correlation between SSF and WBSF (r = .63; p < .01) and both presented moderate correlation with sensorial tenderness (r = - .62 and -.55, to SSF and WBSF, respectively; p < .01). However, WBSF was more efficient to classify samples as tender (68%) than SSF (47%), comparing with sensorial tenderness (80%). There was a moderate correlation for laser and microscopy for sarcomere length (r = .57; p < .01). Sarcomeres were shorter when measured by laser than microscopy. Either with low correlation coefficients, sarcomere measured by laser (r = .29; p < .05) presented higher correlation with sensorial tenderness than with microscopy (r = .22; p < .10). Results highlighted that SSF was faster and easier to run, while WBSF was more appropriate to classify samples by sensorial tenderness grades. Laser diffraction is more suitable to explain effects on tenderness; however, microscopy revealed results of sarcomere length that were more realistic, once laser can underestimate sarcomeres.

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PURPOSE OF REVIEW: Four-dimensional (4D)-Flow cardiovascular magnetic resonance (CMR) is three-dimensional, time-resolved, three-directional velocity-encoded magnetic resonance that provides flow velocity data within a volumetric region across the cardiac cycle (CC). The goals of this paper are to review the current clinical applications of this technique; provide an overview of the general physics; discuss key points from the expert consensus document; and present recent advances in the field. The advantages and disadvantages of 4D-Flow CMR in comparison with the standard and gold standard methods are summarized. RECENT FINDINGS: 4D-Flow CMR offers unique insights into cardiac and circulatory physiology with an ability to quantify advanced hemodynamic parameters in a variety of pathologic entities including aortic and pulmonary artery diseases, valvular heart disease, complex congenital heart disease, and extra-thoracic cardiovascular diseases. Recent large cohort studies highlight how it provides information that has clinical impact beyond a better understanding of the disease and that will permit better and more timely management and prognosis. 4D-Flow CMR provides unique qualitative and quantitative flow dynamics information and its impact on cardiac chambers, vessel walls, and myocardium. As scan acquisition and post-processing of 4D-Flow CMR become faster and simpler, the investigational and clinical opportunities will expand dramatically.

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OBJECTIVE: To evaluate an automatic correction method for velocity offset errors in cardiac 4D-flow acquisitions. MATERIALS AND METHODS: Velocity offset correction was done in a plane-by-plane scheme and compared to a volumetric approach. Stationary regions were automatically detected. In vitro experiments were conducted in a phantom using two orientations and two encoding velocities (Venc). First- to third-order models were fit to the time-averaged images of the three velocity components. In vivo experiments included realistic ROIs in a volunteer superimposed to a phantom. In 15 volunteers, blood flow volume of the proximal and distal descending aorta, of the pulmonary artery (Qp) and the ascending aorta (Qs) was compared. RESULTS: Offset errors were reduced after correction with a third-order model, yielding residual phantom velocities below 0.6 cm/s and 0.4% of Venc. The plane-by-plane correction method was more effective than the volumetric approach. Mean velocities through superimposed ROIs of a volunteer vs phantom were highly correlated (r2 = 0.96). The significant difference between proximal and distal descending aortic flows was decreased after correction from 8.1 to - 1.4 ml (p < 0.001) and Qp/Qs reduced from 1.08 ± 0.09 to 1.01 ± 0.05. DISCUSSION: An automatic third-order model corrected velocity offset errors in 4D-flow acquisitions, achieving acceptable levels for clinical applications.

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BACKGROUND: Idiopathic normal pressure hydrocephalus (iNPH) is a cause of dementia that can be reversed when treated timely with cerebrospinal fluid (CSF) diversion. Understanding CSF dynamics throughout the development of hydrocephalus is crucial to identify prognostic markers to estimate benefit/risk to shunts. OBJECTIVE: To explore the cerebral aqueduct CSF flow dynamics with phase-contrast magnetic resonance imaging (MRI) in a novel rodent model of adult chronic communicating hydrocephalus. METHODS: Kaolin was injected into the subarachnoid space at the convexities in Sprague-Dawley adult rats. 11.7-T Bruker MRI was used to acquire T2-weighted images for anatomic identification and phase-contrast MRI at the cerebral aqueduct. Aqueductal stroke volume (ASV) results were compared with the ventricular volume (VV) at 15, 60, 90, and 120 days. RESULTS: Significant ventricular enlargement was found in kaolin-injected animals at all times (P < 0.001). ASV differed between cases and controls/shams at every time point (P = 0.004, 0.001, 0.001, and <0.001 at 15, 60, 90, and 120 days, respectively). After correlation between the ASV and the VV, there was a significant correlation at 15 (P = 0.015), 60 (P = 0.001), 90 (P < 0.001), and 120 days. Moreover, there was a significant positive correlation between the VV expansion and the aqueductal CSF stroke between 15 and 60 days. CONCLUSIONS: An initial active phase of rapid ventricular enlargement shows a strong correlation between the expansion of the VV and the increment in the ASV during the first 60 days, followed by a second phase with less ventricular enlargement and heterogeneous behavior in the ASV. Further correlation with complementary data from intracranial pressure and histologic/microstructural brain parenchyma assessments are needed to better understand the ASV variations after 60 days.

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Machu Picchu Inca sanctuary (Cusco Region, Peru) was constructed on a granitic plateau, better known as Vilcabamba batholith. One of the most important carved granitic rocks from this archaeological site is the Sacred Rock, used by Inca citizens for religious rituals. Due to the location and climatic conditions, different rocks from this archaeological site are affected by biocolonizations. Concretely, the Sacred Rock shows flaking and delamination problems. In this work, a non-destructive multi analytical methodology has been applied to determine the possible role of the biodeteriogens, forming the biological patina on the Sacred Rock, in the previously mentioned conservation problems. Before characterizing the biological patina, a mineralogical characterization of the granitic substrate was conducted using X-ray Diffraction, Raman microscopy (RM) and micro energy dispersive X-ray fluorescence spectrometry. For the identification of the main biodeteriogens in the biofilm, Phase Contrast Microscopy was used. RM also allowed to determine the distribution (imaging) and the penetration (depth profiling) of the biogenic pigments present in the biopatina. Thanks to this study, it was possible to asses that some colonizers are growing on inner areas of the rock, reinforcing their possible assistance in the delamination. Moreover, the in-depth distribution of a wide variety of carotenoids in the patinas allowed to approach the penetration ability of the main biodeteriogens and the diffusion of these biogenic pigments to the inner areas of the rocky substrate.

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The relative pressure difference across stenotic blood vessels serves as an important clinical index for the diagnosis of many cardiovascular diseases. While the clinical gold standard for relative pressure difference measurements is invasive catheterization, Phase-Contrast Magnetic Resonance Imaging has emerged as a promising tool for enabling a noninvasive quantification, by linking highly spatially resolved velocity measurements with relative pressures via the incompressible Navier-Stokes equations. In this work, we provide a review and analysis of current methods for relative pressure estimation and propose 3 additional techniques. Methods are compared using synthetic data from numerical examples, and sensitivity to subsampling and noise was explored. Through our analysis, we verify that the newly proposed approaches are more robust with respect to spatial subsampling and less sensitive to noise and therefore provide improved means for estimating relative pressure differences noninvasively.

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Microtomography using synchrotron sources is a useful tool in biological imaging research since the phase coherence of synchrotron beams can be exploited to obtain images with high contrast resolution. This work is part of a series of works using phase contrast synchrotron microtomography in the study of Rhodnius prolixus head, the insect vector of Chagas' disease, responsible for about 12,000 deaths per year. The control of insect vector is the most efficient method to prevent this disease and studies have shown that the use of triflumuron, a chitin synthesis inhibitor, disrupted chitin synthesis during larval development and it's an alternative method against insect pests. The aim of this work was to investigate the biological effects of treatments with triflumuron in the ecdysis period (the moulting of the R. prolixus cuticle) using the new imaging beamline IMX at LNLS (Brazilian Synchrotron Light Laboratory). Nymphs of R. prolixus were taken from the Laboratory of Biochemistry and Physiology of Insects, Oswaldo Cruz Foundation, Brazil. Doses of 0.05mg of triflumuron were applied directly to the abdomen on half of the insects immediately after feeding. The insects were sacrificed 25days after feeding (intermoulting period) and fixed with glutaraldehyde. The results obtained using phase contrast synchrotron microtomography in R. prolixus showed amazing images of the effects of triflumuron on insects in the ecdysis period, and the formation of the new cuticle on those which were not treated with triflumuron. Both formation and malformation of this insect's cuticle have never been seen before with this technique.

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PURPOSE: Phase-contrast mammography with synchrotron radiation is an innovative X-ray imaging practice that improves the identification of breast lesions. Previous studies have proven the superiority of the mammography images taken in the phase-contrast modality using synchrotron radiation beams as compared with images taken in conventional mammography by subjective analyses. However, to our knowledge, no previous study has compared different acquisition systems in order to quantify this improvement by means of objective robust indicators. In this research, we intend to quantify the superiority of phase-contrast imaging by means of objective metrics of image quality. METHODS: Images from the American College of Radiology Mammographic Accreditation Phantom were obtained at hospitals, in two digital mammography equipment and at the Elettra synchrotron radiation facility (Trieste, Italy), using free space propagation phase-contrast modality. Regions of interest were selected to analyze image quality at the fibers (phase object) and masses (area object) simulated on the phantom by means of the signal-to-noise ratio, the figure of merit, the contrast and the edge visibility. RESULTS: The image contrast and edge visibility were significantly higher at the phase-contrast modality as compared with digital mammography equipment. The figure of merit using phase-contrast modality was higher for the fibers and comparable for the masses. CONCLUSION: The results showed an improvement of the contrast and edge visibility in phase-contrast images. These improvements may be important in the detection of small lesions and details.

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Non-destructive quality assessment of food prior to processing is desirable in commercial facilities due to its non-invasive nature, for economic reasons and for its safety appeals. Grading Brazil nuts in this way allows for the separation of undesirable nuts to avoid contamination during the automatic nut-shelling process. The aim of this study was to evaluate the feasibility of X-ray phase contrast enhanced imaging in assessing nut quality. For this goal, details of the imaging technique are described and phase contrast X-ray and microtomography imaging of nut samples are investigated. Both high quality (i.e. sound) nuts as well as treated nuts were examined. It was concluded that both the X-ray imaging and tomography techniques have the potential to discriminate morphological features of the nut and to identify sound kernels from atypical ones. Larger nuts and nuts with a larger gap area between shell and kernel were concluded to have more atypical formations. Both techniques also seemed promising for use in automatic sorting lines. However, by using microtomography, the visualization of finer formations not noticeable in the X-ray images was possible. Further studies shall be carried out to investigate the nature of these formations, how they affect nut quality and their evolution with storage time.(AU)

Atualmente os grandes centros comerciais de processamento de alimentos buscam a avaliação prévia da qualidade dos produtos através de técnicas não destrutivas, devido aos apelos econômicos e de segurança alimentar. A classificação de castanhas-do-brasil através desta avaliação permite a separação das castanhas indesejáveis com a finalidade de evitar contaminações durante o processo de extração da amêndoa. O objetivo desse estudo foi avaliar a viabilidade do uso da imagem de raios-X, obtida através da técnica de contraste de fase para avaliação da qualidade da castanha. Para este objetivo, detalhes da técnica de são descritos e amostras de castanhas-do-brasil são investigadas pelas técnicas de imageamento por microtomografia e por contraste de fase de raios-X. São utilizadas castanhas saudáveis e castanhas tratadas, sendo estas últimas utilizadas com o objetivo de identificar modificações. Concluiu-se que ambas as imagens de radiografia e de tomografia de raios-X, apresentam um grande potencial para discriminar características morfológicas das castanhas e selecionar amostras saudáveis das tratadas. Dentro do conjunto de amostragem, castanhas grandes e castanhas que apresentam espaços maiores entre casca e amêndoa, mostraram formações atípicas. Ambas as técnicas mostraram-se também promissoras para serem utilizadas em linhas de produção automatizadas. Não obstante...(AU)

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Non-destructive quality assessment of food prior to processing is desirable in commercial facilities due to its non-invasive nature, for economic reasons and for its safety appeals. Grading Brazil nuts in this way allows for the separation of undesirable nuts to avoid contamination during the automatic nut-shelling process. The aim of this study was to evaluate the feasibility of X-ray phase contrast enhanced imaging in assessing nut quality. For this goal, details of the imaging technique are described and phase contrast X-ray and microtomography imaging of nut samples are investigated. Both high quality (i.e. sound) nuts as well as treated nuts were examined. It was concluded that both the X-ray imaging and tomography techniques have the potential to discriminate morphological features of the nut and to identify sound kernels from atypical ones. Larger nuts and nuts with a larger gap area between shell and kernel were concluded to have more atypical formations. Both techniques also seemed promising for use in automatic sorting lines. However, by using microtomography, the visualization of finer formations not noticeable in the X-ray images was possible. Further studies shall be carried out to investigate the nature of these formations, how they affect nut quality and their evolution with storage time.

Atualmente os grandes centros comerciais de processamento de alimentos buscam a avaliação prévia da qualidade dos produtos através de técnicas não destrutivas, devido aos apelos econômicos e de segurança alimentar. A classificação de castanhas-do-brasil através desta avaliação permite a separação das castanhas indesejáveis com a finalidade de evitar contaminações durante o processo de extração da amêndoa. O objetivo desse estudo foi avaliar a viabilidade do uso da imagem de raios-X, obtida através da técnica de contraste de fase para avaliação da qualidade da castanha. Para este objetivo, detalhes da técnica de são descritos e amostras de castanhas-do-brasil são investigadas pelas técnicas de imageamento por microtomografia e por contraste de fase de raios-X. São utilizadas castanhas saudáveis e castanhas tratadas, sendo estas últimas utilizadas com o objetivo de identificar modificações. Concluiu-se que ambas as imagens de radiografia e de tomografia de raios-X, apresentam um grande potencial para discriminar características morfológicas das castanhas e selecionar amostras saudáveis das tratadas. Dentro do conjunto de amostragem, castanhas grandes e castanhas que apresentam espaços maiores entre casca e amêndoa, mostraram formações atípicas. Ambas as técnicas mostraram-se também promissoras para serem utilizadas em linhas de produção automatizadas. Não obstante...

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Introdução: A sedimentoscopia urinária com microscópio munido com contraste de fase (MCF) deveria ser a primeira etapa na determinação da origemdas hematúrias. Objetivo: Avaliar discrepâncias nas descrições dos parâmetros urinários relacionados à origem das hematúrias, comparando as descrições do nefrologista (Nef) e do profissional de análises clínicas (PAC). Métodos: Urinas de pacientes com glomerulopatias (GP) confirmadas por biópsia renal foram analisadas sob MCF, por um Nef e um PAC, ambos sem conhecimento prévio da origem das amostras. Cilindros hemáticos, acantocitúria ou células G1 >5% e dismorfismo eritrocitário foram utilizados na localização glomerular das hematúrias. Resultados: Dos 28 pacientes, 13 pacientes (46,4%) apresentavam glomerulonefrites não proliferativas e 15 (53,6%) glomerulonefrites proliferativas. Comparativamente ao PAC, o Nef identificou maior número de hemácias (mediana/mL de urina, 80.000 vs 4.800, p=0,001), maior número de cilindros hemáticos (39,3% vs 0%, p=0,001), maior freqüência de acantocitúria ou células G1 >5% (35,7% vs. 7,14%, p=0,021) e de dismorfismo eritrocitário (96,2% vs 7,14%, p<0,001). As discrepâncias dos resultados permaneceram após a separação das glomerulopatias em proliferativas e não proliferativas. Conclusão: Os parâmetros urinários que caracterizam a origem da hematúria foram mais freqüentemente identificados pelo nefrologista e sugerem que a urinálise, pela sua simplicidade e grande valor informativo, deveria ser incluída obrigatoriamente nos programas de treinamento em nefrologia.

Introduction: In the assessment of hematuria, the first step should be the identification of the origin of the bleeding, which can be done easily by analyzing the urine under phase-contrast microscopy. Obective: To assess the discrepancy of reports of the urinary parameters utilized in the localization of the glomerular origin of hematuria, comparing reports by the nephrologists and by the clinical laboratory technologist. Methods: Urines of patients with biopsy proven glomerulonephritis were assessed under phase-contrast microscopy by a nephrologist and a clinical laboratory technologist, both without previous knowledge of the origin of the samples. Red blood cell (RBC) casts, urinary acanthocytes or G1 cells >5%, and erithrocyte dysmorphism were used tolocalize the glomerular bleeding. Results: Among 28 patients, 13 (46.4%) had non proliferative glomerulonephritis and 15 (53.6%) had proliferative glomerulonephritis. Relatively to the clinical laboratory technologist, the nephrologist identified more RBC (median of 80.000 vs 4.800, p= 0.001), more RBC casts (39.3% vs 0%, p=0.001), more urinary acanthocytes or G1 cells >5% (35.7% vs 7.14%, p=0.021) and more dysmorphic RBC (96.2% vs 7.14%,p<0.001). The discrepancies of the reports were maintained after the separation of the glomerulonephritis in proliferative and non proliferative. Conclusion: The urinary parameters used in characterization of the origin of the hematuria were more frequently identified by the nephrologist, and suggest that the urinalysis, a simple and very informative test, should be mandatory in programs of training in nephrology.

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