Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STI... more Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STIR and T2 SPAIR-in terms of image quality, as well as in terms of their diagnostic performance in detecting sacroiliac joints (SIJ) active inflammation. Materials and Methods: We included 69 consecutive patients with suspected spondyloarthritis undergoing MRI between 2012 and 2014. The signal-to-noise ratio (SNR) was calculated with the method recommended by the American College of Radiology. Two readers evaluated SIJ MRI following ASAS criteria to assess diagnostic performance regarding the detection of active SIJ inflammation. T1 SPIR Gd+ sequence was used as the reference standard. Results: The mean SNR was 72.8 for the T1 SPIR Gd+ sequence, compared with 14.1 and 37.6 for the STIR and T2 SPAIR sequences, respectively. The sensitivity and specificity of STIR and SPAIR T2 sequences did not show any statistically significant differences, for the diagnosis of sacroiliitis with active infl...
The standard reference to evaluate active inflammation of sacroiliac joints in spondyloarthritis ... more The standard reference to evaluate active inflammation of sacroiliac joints in spondyloarthritis is magnetic resonance imaging (MRI). However, visual evaluation may be challenging to specialists due to clinical variability. In order to improve the diagnosis of inflammatory sacroiliitis we have used image processing and machine learning technics to recognize inflammatory patterns in sacroiliac joints in spectral attenuated inversion recovery (SPAIR) T2-weighted MRI using gray-level, texture and spectral features. Pattern recognition was performed by the ReliefF method for attribute selection and the classifiers K nearest neighbors (with 5 values for K), Multilayer Perceptron artificial neural network, Naive Bayes, Random Forest, and Decision Tree J48. Classification was assessed by the area under the ROC (receiver operating characteristic) curve (AUC), Sensitivity and Specificity, with a 10-fold cross validation. The K nearest neighbors with K = 5 obtained the best performance with A...
Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STI... more Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STIR and T2 SPAIR-in terms of image quality, as well as in terms of their diagnostic performance in detecting sacroiliac joints (SIJ) active inflammation. Materials and Methods: We included 69 consecutive patients with suspected spondyloarthritis undergoing MRI between 2012 and 2014. The signal-to-noise ratio (SNR) was calculated with the method recommended by the American College of Radiology. Two readers evaluated SIJ MRI following ASAS criteria to assess diagnostic performance regarding the detection of active SIJ inflammation. T1 SPIR Gd+ sequence was used as the reference standard. Results: The mean SNR was 72.8 for the T1 SPIR Gd+ sequence, compared with 14.1 and 37.6 for the STIR and T2 SPAIR sequences, respectively. The sensitivity and specificity of STIR and SPAIR T2 sequences did not show any statistically significant differences, for the diagnosis of sacroiliitis with active infl...
International Journal of Computer Assisted Radiology and Surgery
To evaluate the performance of texture-based biomarkers by radiomic analysis using magnetic reson... more To evaluate the performance of texture-based biomarkers by radiomic analysis using magnetic resonance imaging (MRI) of patients with sacroiliitis secondary to spondyloarthritis (SpA). Relevance: The determination of sacroiliac joints inflammatory activity supports the drug management in these diseases. Sacroiliac joints (SIJ) MRI examinations of 47 patients were evaluated. Thirty-seven patients had SpA diagnoses (27 axial SpA and ten peripheral SpA) which was established previously after clinical and laboratory follow-up. To perform the analysis, the SIJ MRI was first segmented and warped. Second, radiomics biomarkers were extracted from the warped MRI images for associative analysis with sacroiliitis and the SpA subtypes. Finally, statistical and machine learning methods were applied to assess the associations of the radiomics texture-based biomarkers with clinical outcomes. All diagnostic performances obtained with individual or combined biomarkers reached areas under the receiver operating characteristic curves ≥ 0.80 regarding SpA related sacroiliitis and and SpA subtypes classification. Radiomics texture-based analysis showed significant differences between the positive and negative SpA groups and differentiated the axial and peripheral subtypes (P < 0.001). In addition, the radiomics analysis was also able to correctly identify the disease even in the absence of active inflammation. We concluded that the application of the radiomic approach constitutes a potential noninvasive tool to aid the diagnosis of sacroiliitis and for SpA subclassifications based on MRI of sacroiliac joints.
Background Currently, magnetic resonance imaging (MRI) is used to evaluate active inflammatory sa... more Background Currently, magnetic resonance imaging (MRI) is used to evaluate active inflammatory sacroiliitis related to axial spondyloarthritis (axSpA). The qualitative and semiquantitative diagnosis performed by expert radiologists and rheumatologists remains subject to significant intrapersonal and interpersonal variation. This encouraged us to use machine-learning methods for this task. Methods In this retrospective study including 56 sacroiliac joint MRI exams, 24 patients had positive and 32 had negative findings for inflammatory sacroiliitis according to the ASAS group criteria. The dataset was randomly split with ~ 80% (46 samples, 20 positive and 26 negative) as training and ~ 20% as external test (10 samples, 4 positive and 6 negative). After manual segmentation of the images by a musculoskeletal radiologist, multiple features were extracted. The classifiers used were the Support Vector Machine, the Multilayer Perceptron (MLP), and the Instance-Based Algorithm, combined with...
International Journal of Physical Medicine & Rehabilitation, 2017
Introduction: The International Classification of Functioning, Disability and Health (ICF), descr... more Introduction: The International Classification of Functioning, Disability and Health (ICF), describes the functioning and individuals with particular health condition and how context factors can modulate it. The nontraumatic spinal cord injury (NTSCI) has several effects on the functioning. The ICF Core Set for spinal cord injury (CSSCI) can be an innovative assessment of people with NTSCI functioning, but has not been applied in this context and there are no standardization proposals for its implementation. Objective: To develop a user-friendly instrument based in the International Classification of Functioning, Disability and Health core set for spinal cord injury (CSSCI) to operationalize functioning data of non-traumatic patients. Method: By studying, the particular uses of CSSCI categories to non-traumatic individuals, the researchers developed specific questions with richly described answer alternatives according with the descriptions of ICF qualifiers. For some categories, validated instruments were adapted, for some others new questions were formulated. Results: A questionnaire containing 43 sub-items was developed covering aspects of 9 body functions, 4 body structures, 21 activities and participation and 9 environmental factors. Health professional who tested it did not report difficulties to understand or apply the questionnaire, although it may time consuming. Conclusion: Besides proposing a method to develop ICF based questionnaires, this study developed a functional assessment tool that is very broad in the evaluation of functioning and adds the impact of environmental factors on the overall experience of disability.
Anais do Simpósio Brasileiro de Computação Aplicada à Saúde (SBCAS)
O método referência para avaliar a inflamação nas articulações sacroilíacas (AS) em espondiloartr... more O método referência para avaliar a inflamação nas articulações sacroilíacas (AS) em espondiloartrites é a ressonância magnética (RM). Porém, ele pode apresentar desafios para especialistas devido a sua variabilidade clínica. Neste contexto, este trabalho visa reconhecer padrões inflamatórios de AS em imagens de RM utilizando atributos de níveis de cinza, textura e espectrais. Os atributos foram extraídos de 51 pacientes e selecionados pelo método ReliefF. A classificação foi realizada por métodos de aprendizado de máquina e avaliados pelaárea sob a curva ROC utilizando validação cruzada 10-fold. Resultados mostraram que o método de cinco vizinhos próximos apresentou maior precisão do que os outros classificadores.
This paper contextualizes the environmental reality of the creeks of Manaus along its historic bu... more This paper contextualizes the environmental reality of the creeks of Manaus along its historic building, in particular taking into consideration the changes in the drainage system of the watershed Finch located in the north of Manaus, the main area of growth in recent decades. In this sense, this work aimed to analyze the process of formation of sedimentary tecnógena river bars in that unit as well as to characterize the physical properties based on the gravimetric composition of solid waste and soil analysis through testing and determination of granulometric class's texture. In this sense réalisés tests with soil samples showed the presence of natural sediments: sand, silt and clay and solid waste. The proportion between the two elements corresponds to 96% of natural sediments and 4% of the anthropogenic waste. Regarding the classes of waste was observed by means of gravimetric composition that tecnógena sedimentary bars are constructed of materials: plastic, metal, cloth, rubber, and other organic matter. The ratio of these residues represented in terms of the amount corresponding to 9,016kg value, and the plastic item to be greater, representing 54% of the residues analyzed. Other items that also stood out during weighing were the metal packaging which registered net weight of 1.27 kg, 1.16 kg and fabric rubber with 0,845kg. These results are key to highlight the impacts produced by sedimentary bars in the watershed of the Finch, mainly in relation to the volume of sediment, as these represent direct impact on the flow capacity of rainwater and contributes to the increased risk of flooding and proliferation diseases.
ObjectiveTo evaluate the evolution of the ultrasonographic pubo-femoral distance (PFD) before and... more ObjectiveTo evaluate the evolution of the ultrasonographic pubo-femoral distance (PFD) before and after Pavlik harness treatment for developmental dysplasia of the hip (DDH) in newborns.Patients and methodsTwenty-five patients (16.7 ± 10.4 days; 19 females, six males) diagnosed with DDH and treated using the Pavlik harness were included. Eighteen patients had bilateral, and seven unilateral DDH, with a total of 43 dysplastic hips. The seven non-dysplastic hips in unilateral cases were used for comparison. The PFD was measured in the coronal and axial planes with the hip flexed to approximately 90°, before and after an average of 93 days of treatment. The femoral head coverage was assessed in the coronal plane, and correlated with PFD values.ResultsIn dysplastic hips, the mean PFD decreased from 6.1 ± 1.8 mm to 3.0 ± 0.7 mm in the axial (adjusted difference, 2.9 mm; p < 0.01), and from 5.9 ± 2.0 to 3.0 ± 0.6 mm in the coronal plane (adjusted difference 2.7 mm; p < 0.01). The femoral head coverage increased from 30.8 to 62.1%, and the mean differences of femoral head coverage and PFD were significantly correlated (p < 0.001). There was no difference between treated dysplastic and non-dysplastic hips. There was high intra- and inter-observer agreement for PFD measurements.ConclusionThe PFD decreased significantly after DDH treatment using the Pavlik harness in newborns, and showed significant correlation with the femoral head coverage improvement. PFD might be a reliable tool for monitoring DDH treatment in newborns treated using the Pavlik harness.
Objective: To assess imaging parameters related to the morphology of the glenohumeral joint in ch... more Objective: To assess imaging parameters related to the morphology of the glenohumeral joint in children with unilateral brachial plexus birth palsy (BPBP), in comparison with those obtained for healthy shoulders. Materials and Methods: We conducted a retrospective search for cases of unilateral BPBP diagnosed at our facility. Only patients with a clinical diagnosis of unilateral BPBP were included, and the final study sample consisted of 10 consecutive patients who were assessed with cross-sectional imaging. The glenoid version, the translation of the humeral head, and the degrees of glenohumeral dysplasia were assessed. Results: The mean diameter of the affected humeral heads was 1.93 cm, compared with 2.33 cm for those of the normal limbs. In two cases, there was no significant posterior displacement of the humeral head, five cases showed posterior subluxation of the humeral head, and the remaining three cases showed total luxation of the humeral head. The mean glenoid version ang...
Study design. Cross-sectional observational study on the relationship between the degrees of disc... more Study design. Cross-sectional observational study on the relationship between the degrees of disc degeneration and sagittal alignment in asymptomatic healthy individuals. Objective. This study sought to determine whether the sagittal spine alignment subtype is related to the prevalence of lumbar disc degeneration. Summary and Background Data. Sagittal balance and spinopelvic parameters might be risk factors for disc degeneration. Methods. A total of 70 asymptomatic participants (36 women and 34 men) without regular physical activity were categorized according to the four subtypes of sagittal alignment proposed by Roussouly. All participants underwent magnetic resonance imaging of the lumbar spine (1.5T) and panoramic radiography of the spine. The degree of disc degeneration was graded using T2-weighted images according to the Pfirrmann classification. Spinopelvic parameters and vertebral curvatures were measured on digital panoramic radiographs using Surgimap software. Interobserver analyses for the Pfirrmann classification and spinopelvic parameters were assessed using the weighted Kappa and intraclass correlation coefficient (ICC), respectively. Results. The Kappa associated with disc degeneration classification was 0.79 (95% confidence intervals 0.72-0.87). The ICCs were excellent, with small confidence intervals for all spinopelvic parameters. The type II group (flat lordosis) showed a higher frequency of degenerated discs at L4-L5 (P ¼ 0.03) than the type IV group (long and curved lumbar spine). No significant differences in disc degeneration were observed among the four subtypes at the other disc levels. We found a negative, moderate correlation between the spinopelvic parameters and the occurrence of disc degeneration in the type II group. Conclusion. The Roussouly subtype II sagittal alignment is significantly associated with disc degeneration at L4-L5 in asymptomatic young adults. Our results support the hypothesis that spinal sagittal alignment plays a role in early disc degeneration.
PURPOSE To evaluate if the acetabular epiphyseal distance (AED) has feasibility and reproducibili... more PURPOSE To evaluate if the acetabular epiphyseal distance (AED) has feasibility and reproducibility comparable to the Graf method METHOD AND MATERIALS A retrospective study from January 2010 to March 2012 included 115 patients (230 hips) at risk for developmental dysplasia of the hip (DDH) and underwent ultrasound (US) evaluation between third and fourth week of life. The Graf modified classification was assessed and the hips were distributed in two groups: non-dysplastic (I, IIA) and dysplastic hips (IIC, III, D, IV). AED in coronal neutral and flexion views was assessed by measuring the distance between the acetabular fossa and the medial surface of the femoral head. For both methods there were two readers, one junior and one experienced radiologist (one and seven years of practice, respectively). Interobserver reliability was calculated by intraclass correlation coefficient (ICC). RESULTS 213 hips were non-dysplastic (ND) and 17 dysplastic (DH). In neutral position, AED in ND was...
To evaluate whether the pubo-femoral distance (PFD) can be used as an accurate screening test to ... more To evaluate whether the pubo-femoral distance (PFD) can be used as an accurate screening test to diagnose developmental dysplasia of the hip (DDH) in an at-risk population compared with the Graf method. Second, to determine whether PFD assessment is feasible and reproducible regardless of the observer&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s experience. IRB approved this retrospective single-institution study. Written informed consent was waived. Between January 2010 and March 2012, 116 neonates at risk for DDH were included. Infants&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; hips were distributed into two groups according to recommendation for treatment: non-dysplastic (ND; Graf I/IIA; 211 hips; 69 females/37 males) and dysplastic hip (DH; Graf IIB/IIC/III/D/IV; 21 hips; 8 females/3 males). One resident and one experienced radiologist reviewed ultrasonography images performed in the fourth week. To compare the groups, Student&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s t and Mann-Whitney tests for normally and non-normally distributed covariates were performed. Accuracy of PFD to diagnose DDH was calculated. Intraclass correlation coefficient (ICC) was calculated to assess inter-observer agreement. Mean PFDs of ND group were 3.09mm at neutral position and 3.64mm with the hip flexed. Mean PFDs of DH group were 6.29mm and 7.59mm, respectively. Sensitivity, specificity, and accuracy of PFD were 94.4%, 93.4%, and 97.2% (cut-off=4.6mm) at neutral position and 94.4%, 89.0%, and 95.5% (cut-off=4.9mm) with hip flexed. ICCs were 0.852 and 0.864, respectively. PFD is comparable with Graf method, enabling physicians to differentiate patients who should undergo treatment from those who should not. PFD can be used as a screening tool for diagnosing DDH with high accuracy, even by inexperienced radiologists.
The pathogenesis of endotoxemic tubular dysfunction with failure in urine concentration is poorly... more The pathogenesis of endotoxemic tubular dysfunction with failure in urine concentration is poorly understood. Urea plays an important role in the urinary concentrating mechanism and expression of the urea transporters UT-A1, UT-A2, UT-A3, UT-A4 and UT-B is essential for tubular urea reabsorption. The present study attempts to assess the regulation of renal urea transporters during severe inflammation in vivo. Materials and methods By agreement of the animal protection committee C57BL/6J, mice were injected with lipopolysaccharides (LPS, 10 mg/kg) or proinflammatory cytokines. Hemodynamic, renal parameters and the expression of renal urea transporters were investigated. To clarify the role of cytokines and renal ischemia in the regulation of renal urea transporters, experiments were performed with cytokine knockout mice, mice treated with low-dose LPS (1, 5 mg/kg) as a sepsis model without induction of hypotension, glucocorticoid-treated mice, and mice with renal artery clipping serving as a model for renal ischemia. Results and discussion LPS-injected mice (10 mg/kg) presented with reduced glomerular filtration rate, fractional urea excretion and inner medulla osmolality associated with a marked decrease in expression of UT-A1, UT-A2, UT-A3, UT-A4 and UT-B (Figure ). Similar alterations were observed after application of TNFα, IL-1β, IFNγ or IL-6. LPS-induced downregulation of urea transporters was not affected in knockout mice with deficient TNFα, IL-receptor-1, IFNγ or IL-6. Glucocorticoid treatment inhibited LPS-induced increases of tissue TNFα, IL-1β, IFNγ or IL-6 concentration, diminished LPS-induced renal dysfunction and attenuated the downregulation of renal urea transporters. Injection of low-dose LPS (1, 5 mg/kg) also led to renal dysfunction paralleled by a downregulation of renal urea transporters without alterations in blood pressure. Renal ischemia induced by renal artery clipping did not influence the expression of urea transporters. Conclusion Our findings demonstrate downregulation of renal urea transporters that probably accounts for tubular dysfunction during sepsis. Furthermore, they suggest that downregulation of Figure 1 (abstract P1) Effect of lipopolysaccharide (LPS) (10 mg/kg), dexamethasone (10 mg/kg) and the combination of both on UT-A1, UT-A2, UT-A3, UT-A4 and UT-B mRNA in the kidney 6, 12 and 24 hours after intraperitoneal injection. Values are related to signals obtained for β-actin mRNA and presented as the percentage of vehicle control. Mean ± SEM of six animals per group. *P < 0.05 versus control, # P < 0.05 versus LPS treatment. S2
Background and purpose: Sepsis is a systemic inflammatory response resulting from the inability o... more Background and purpose: Sepsis is a systemic inflammatory response resulting from the inability of the host to restrict local infection. The failure of neutrophil migration to the infection site is one of the mechanisms involved in this process. Recently, it was demonstrated that this event is mediated by nitric oxide (NO). The present study addresses the possibility that peroxynitrite (ONOO-), a NO-derived powerful oxidizing and nitrating compound, could also be involved in neutrophil migration failure. Experimental approach: Male C57Bl/6 mice were subjected to moderate (MSI) or severe (SSI) septic injury, both induced by cecal ligation and puncture (CLP). The leukocyte rolling and adhesion in the mesentery was evaluated by intravital microscopy. Cytokines (TNF-a and MIP-1a) were measured by ELISA and 3-nitrotyrosine (3-NT) by immunofluorescence. Key results: Compared with saline pretreatment of SSI mice, pre-treatment with uric acid, a ONOOscavenger, partially restored the failure of neutrophil rolling, adhesion and migration to the site of infection. These mice also presented low circulating bacterial counts and diminished systemic inflammatory response. Pretreatment with uric acid reduced 3-NT labelling in leukocytes in mesenteric tissues and in neutrophils obtained from peritoneal exudates. Finally, uric acid pretreatment enhanced significantly the survival rate in the SSI mice. Similarly, treatment with FeTPPs, a more specific ONOOscavenger, re-established neutrophil migration and increased mice survival rate. Conclusions and implications: These results indicate that ONOOcontributed to the reduction of neutrophil/endothelium interaction and the consequent failure of neutrophil migration into infection foci and hence susceptibility to severe sepsis.
Anais Principais do Simpósio Brasileiro de Computação Aplicada à Saúde (SBCAS 2020)
In an attempt to aid the subtyping of spondyloarthritis (SpA), this work assessed neural nets and... more In an attempt to aid the subtyping of spondyloarthritis (SpA), this work assessed neural nets and magnetic resonance imaging (MRI) features to predict SpA. Patients underwent SPAIR and STIR MRI sequences. Radiologists manually segmented sacroiliac joints images for extracting MRI features. A neural net used these features to predict SpA. The STIR-based model yielded higher performance than SPAIR to diagnose SpA, although no statistical difference was found between them. The SPAIR model yielded an area under the curve of 0.83 to differentiate axial and peripheral subtypes, while STIR yielded 0.57 (p < 0.05 on curves difference). Therefore, neural nets modeled with SPAIR-extracted features distinguished SpA using a single MRI exam of the sacroiliac joints.
Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STI... more Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STIR and T2 SPAIR-in terms of image quality, as well as in terms of their diagnostic performance in detecting sacroiliac joints (SIJ) active inflammation. Materials and Methods: We included 69 consecutive patients with suspected spondyloarthritis undergoing MRI between 2012 and 2014. The signal-to-noise ratio (SNR) was calculated with the method recommended by the American College of Radiology. Two readers evaluated SIJ MRI following ASAS criteria to assess diagnostic performance regarding the detection of active SIJ inflammation. T1 SPIR Gd+ sequence was used as the reference standard. Results: The mean SNR was 72.8 for the T1 SPIR Gd+ sequence, compared with 14.1 and 37.6 for the STIR and T2 SPAIR sequences, respectively. The sensitivity and specificity of STIR and SPAIR T2 sequences did not show any statistically significant differences, for the diagnosis of sacroiliitis with active infl...
The standard reference to evaluate active inflammation of sacroiliac joints in spondyloarthritis ... more The standard reference to evaluate active inflammation of sacroiliac joints in spondyloarthritis is magnetic resonance imaging (MRI). However, visual evaluation may be challenging to specialists due to clinical variability. In order to improve the diagnosis of inflammatory sacroiliitis we have used image processing and machine learning technics to recognize inflammatory patterns in sacroiliac joints in spectral attenuated inversion recovery (SPAIR) T2-weighted MRI using gray-level, texture and spectral features. Pattern recognition was performed by the ReliefF method for attribute selection and the classifiers K nearest neighbors (with 5 values for K), Multilayer Perceptron artificial neural network, Naive Bayes, Random Forest, and Decision Tree J48. Classification was assessed by the area under the ROC (receiver operating characteristic) curve (AUC), Sensitivity and Specificity, with a 10-fold cross validation. The K nearest neighbors with K = 5 obtained the best performance with A...
Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STI... more Objective: To compare two different fat-saturated magnetic resonance imaging (MRI) techniques-STIR and T2 SPAIR-in terms of image quality, as well as in terms of their diagnostic performance in detecting sacroiliac joints (SIJ) active inflammation. Materials and Methods: We included 69 consecutive patients with suspected spondyloarthritis undergoing MRI between 2012 and 2014. The signal-to-noise ratio (SNR) was calculated with the method recommended by the American College of Radiology. Two readers evaluated SIJ MRI following ASAS criteria to assess diagnostic performance regarding the detection of active SIJ inflammation. T1 SPIR Gd+ sequence was used as the reference standard. Results: The mean SNR was 72.8 for the T1 SPIR Gd+ sequence, compared with 14.1 and 37.6 for the STIR and T2 SPAIR sequences, respectively. The sensitivity and specificity of STIR and SPAIR T2 sequences did not show any statistically significant differences, for the diagnosis of sacroiliitis with active infl...
International Journal of Computer Assisted Radiology and Surgery
To evaluate the performance of texture-based biomarkers by radiomic analysis using magnetic reson... more To evaluate the performance of texture-based biomarkers by radiomic analysis using magnetic resonance imaging (MRI) of patients with sacroiliitis secondary to spondyloarthritis (SpA). Relevance: The determination of sacroiliac joints inflammatory activity supports the drug management in these diseases. Sacroiliac joints (SIJ) MRI examinations of 47 patients were evaluated. Thirty-seven patients had SpA diagnoses (27 axial SpA and ten peripheral SpA) which was established previously after clinical and laboratory follow-up. To perform the analysis, the SIJ MRI was first segmented and warped. Second, radiomics biomarkers were extracted from the warped MRI images for associative analysis with sacroiliitis and the SpA subtypes. Finally, statistical and machine learning methods were applied to assess the associations of the radiomics texture-based biomarkers with clinical outcomes. All diagnostic performances obtained with individual or combined biomarkers reached areas under the receiver operating characteristic curves ≥ 0.80 regarding SpA related sacroiliitis and and SpA subtypes classification. Radiomics texture-based analysis showed significant differences between the positive and negative SpA groups and differentiated the axial and peripheral subtypes (P < 0.001). In addition, the radiomics analysis was also able to correctly identify the disease even in the absence of active inflammation. We concluded that the application of the radiomic approach constitutes a potential noninvasive tool to aid the diagnosis of sacroiliitis and for SpA subclassifications based on MRI of sacroiliac joints.
Background Currently, magnetic resonance imaging (MRI) is used to evaluate active inflammatory sa... more Background Currently, magnetic resonance imaging (MRI) is used to evaluate active inflammatory sacroiliitis related to axial spondyloarthritis (axSpA). The qualitative and semiquantitative diagnosis performed by expert radiologists and rheumatologists remains subject to significant intrapersonal and interpersonal variation. This encouraged us to use machine-learning methods for this task. Methods In this retrospective study including 56 sacroiliac joint MRI exams, 24 patients had positive and 32 had negative findings for inflammatory sacroiliitis according to the ASAS group criteria. The dataset was randomly split with ~ 80% (46 samples, 20 positive and 26 negative) as training and ~ 20% as external test (10 samples, 4 positive and 6 negative). After manual segmentation of the images by a musculoskeletal radiologist, multiple features were extracted. The classifiers used were the Support Vector Machine, the Multilayer Perceptron (MLP), and the Instance-Based Algorithm, combined with...
International Journal of Physical Medicine & Rehabilitation, 2017
Introduction: The International Classification of Functioning, Disability and Health (ICF), descr... more Introduction: The International Classification of Functioning, Disability and Health (ICF), describes the functioning and individuals with particular health condition and how context factors can modulate it. The nontraumatic spinal cord injury (NTSCI) has several effects on the functioning. The ICF Core Set for spinal cord injury (CSSCI) can be an innovative assessment of people with NTSCI functioning, but has not been applied in this context and there are no standardization proposals for its implementation. Objective: To develop a user-friendly instrument based in the International Classification of Functioning, Disability and Health core set for spinal cord injury (CSSCI) to operationalize functioning data of non-traumatic patients. Method: By studying, the particular uses of CSSCI categories to non-traumatic individuals, the researchers developed specific questions with richly described answer alternatives according with the descriptions of ICF qualifiers. For some categories, validated instruments were adapted, for some others new questions were formulated. Results: A questionnaire containing 43 sub-items was developed covering aspects of 9 body functions, 4 body structures, 21 activities and participation and 9 environmental factors. Health professional who tested it did not report difficulties to understand or apply the questionnaire, although it may time consuming. Conclusion: Besides proposing a method to develop ICF based questionnaires, this study developed a functional assessment tool that is very broad in the evaluation of functioning and adds the impact of environmental factors on the overall experience of disability.
Anais do Simpósio Brasileiro de Computação Aplicada à Saúde (SBCAS)
O método referência para avaliar a inflamação nas articulações sacroilíacas (AS) em espondiloartr... more O método referência para avaliar a inflamação nas articulações sacroilíacas (AS) em espondiloartrites é a ressonância magnética (RM). Porém, ele pode apresentar desafios para especialistas devido a sua variabilidade clínica. Neste contexto, este trabalho visa reconhecer padrões inflamatórios de AS em imagens de RM utilizando atributos de níveis de cinza, textura e espectrais. Os atributos foram extraídos de 51 pacientes e selecionados pelo método ReliefF. A classificação foi realizada por métodos de aprendizado de máquina e avaliados pelaárea sob a curva ROC utilizando validação cruzada 10-fold. Resultados mostraram que o método de cinco vizinhos próximos apresentou maior precisão do que os outros classificadores.
This paper contextualizes the environmental reality of the creeks of Manaus along its historic bu... more This paper contextualizes the environmental reality of the creeks of Manaus along its historic building, in particular taking into consideration the changes in the drainage system of the watershed Finch located in the north of Manaus, the main area of growth in recent decades. In this sense, this work aimed to analyze the process of formation of sedimentary tecnógena river bars in that unit as well as to characterize the physical properties based on the gravimetric composition of solid waste and soil analysis through testing and determination of granulometric class's texture. In this sense réalisés tests with soil samples showed the presence of natural sediments: sand, silt and clay and solid waste. The proportion between the two elements corresponds to 96% of natural sediments and 4% of the anthropogenic waste. Regarding the classes of waste was observed by means of gravimetric composition that tecnógena sedimentary bars are constructed of materials: plastic, metal, cloth, rubber, and other organic matter. The ratio of these residues represented in terms of the amount corresponding to 9,016kg value, and the plastic item to be greater, representing 54% of the residues analyzed. Other items that also stood out during weighing were the metal packaging which registered net weight of 1.27 kg, 1.16 kg and fabric rubber with 0,845kg. These results are key to highlight the impacts produced by sedimentary bars in the watershed of the Finch, mainly in relation to the volume of sediment, as these represent direct impact on the flow capacity of rainwater and contributes to the increased risk of flooding and proliferation diseases.
ObjectiveTo evaluate the evolution of the ultrasonographic pubo-femoral distance (PFD) before and... more ObjectiveTo evaluate the evolution of the ultrasonographic pubo-femoral distance (PFD) before and after Pavlik harness treatment for developmental dysplasia of the hip (DDH) in newborns.Patients and methodsTwenty-five patients (16.7 ± 10.4 days; 19 females, six males) diagnosed with DDH and treated using the Pavlik harness were included. Eighteen patients had bilateral, and seven unilateral DDH, with a total of 43 dysplastic hips. The seven non-dysplastic hips in unilateral cases were used for comparison. The PFD was measured in the coronal and axial planes with the hip flexed to approximately 90°, before and after an average of 93 days of treatment. The femoral head coverage was assessed in the coronal plane, and correlated with PFD values.ResultsIn dysplastic hips, the mean PFD decreased from 6.1 ± 1.8 mm to 3.0 ± 0.7 mm in the axial (adjusted difference, 2.9 mm; p < 0.01), and from 5.9 ± 2.0 to 3.0 ± 0.6 mm in the coronal plane (adjusted difference 2.7 mm; p < 0.01). The femoral head coverage increased from 30.8 to 62.1%, and the mean differences of femoral head coverage and PFD were significantly correlated (p < 0.001). There was no difference between treated dysplastic and non-dysplastic hips. There was high intra- and inter-observer agreement for PFD measurements.ConclusionThe PFD decreased significantly after DDH treatment using the Pavlik harness in newborns, and showed significant correlation with the femoral head coverage improvement. PFD might be a reliable tool for monitoring DDH treatment in newborns treated using the Pavlik harness.
Objective: To assess imaging parameters related to the morphology of the glenohumeral joint in ch... more Objective: To assess imaging parameters related to the morphology of the glenohumeral joint in children with unilateral brachial plexus birth palsy (BPBP), in comparison with those obtained for healthy shoulders. Materials and Methods: We conducted a retrospective search for cases of unilateral BPBP diagnosed at our facility. Only patients with a clinical diagnosis of unilateral BPBP were included, and the final study sample consisted of 10 consecutive patients who were assessed with cross-sectional imaging. The glenoid version, the translation of the humeral head, and the degrees of glenohumeral dysplasia were assessed. Results: The mean diameter of the affected humeral heads was 1.93 cm, compared with 2.33 cm for those of the normal limbs. In two cases, there was no significant posterior displacement of the humeral head, five cases showed posterior subluxation of the humeral head, and the remaining three cases showed total luxation of the humeral head. The mean glenoid version ang...
Study design. Cross-sectional observational study on the relationship between the degrees of disc... more Study design. Cross-sectional observational study on the relationship between the degrees of disc degeneration and sagittal alignment in asymptomatic healthy individuals. Objective. This study sought to determine whether the sagittal spine alignment subtype is related to the prevalence of lumbar disc degeneration. Summary and Background Data. Sagittal balance and spinopelvic parameters might be risk factors for disc degeneration. Methods. A total of 70 asymptomatic participants (36 women and 34 men) without regular physical activity were categorized according to the four subtypes of sagittal alignment proposed by Roussouly. All participants underwent magnetic resonance imaging of the lumbar spine (1.5T) and panoramic radiography of the spine. The degree of disc degeneration was graded using T2-weighted images according to the Pfirrmann classification. Spinopelvic parameters and vertebral curvatures were measured on digital panoramic radiographs using Surgimap software. Interobserver analyses for the Pfirrmann classification and spinopelvic parameters were assessed using the weighted Kappa and intraclass correlation coefficient (ICC), respectively. Results. The Kappa associated with disc degeneration classification was 0.79 (95% confidence intervals 0.72-0.87). The ICCs were excellent, with small confidence intervals for all spinopelvic parameters. The type II group (flat lordosis) showed a higher frequency of degenerated discs at L4-L5 (P ¼ 0.03) than the type IV group (long and curved lumbar spine). No significant differences in disc degeneration were observed among the four subtypes at the other disc levels. We found a negative, moderate correlation between the spinopelvic parameters and the occurrence of disc degeneration in the type II group. Conclusion. The Roussouly subtype II sagittal alignment is significantly associated with disc degeneration at L4-L5 in asymptomatic young adults. Our results support the hypothesis that spinal sagittal alignment plays a role in early disc degeneration.
PURPOSE To evaluate if the acetabular epiphyseal distance (AED) has feasibility and reproducibili... more PURPOSE To evaluate if the acetabular epiphyseal distance (AED) has feasibility and reproducibility comparable to the Graf method METHOD AND MATERIALS A retrospective study from January 2010 to March 2012 included 115 patients (230 hips) at risk for developmental dysplasia of the hip (DDH) and underwent ultrasound (US) evaluation between third and fourth week of life. The Graf modified classification was assessed and the hips were distributed in two groups: non-dysplastic (I, IIA) and dysplastic hips (IIC, III, D, IV). AED in coronal neutral and flexion views was assessed by measuring the distance between the acetabular fossa and the medial surface of the femoral head. For both methods there were two readers, one junior and one experienced radiologist (one and seven years of practice, respectively). Interobserver reliability was calculated by intraclass correlation coefficient (ICC). RESULTS 213 hips were non-dysplastic (ND) and 17 dysplastic (DH). In neutral position, AED in ND was...
To evaluate whether the pubo-femoral distance (PFD) can be used as an accurate screening test to ... more To evaluate whether the pubo-femoral distance (PFD) can be used as an accurate screening test to diagnose developmental dysplasia of the hip (DDH) in an at-risk population compared with the Graf method. Second, to determine whether PFD assessment is feasible and reproducible regardless of the observer&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s experience. IRB approved this retrospective single-institution study. Written informed consent was waived. Between January 2010 and March 2012, 116 neonates at risk for DDH were included. Infants&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; hips were distributed into two groups according to recommendation for treatment: non-dysplastic (ND; Graf I/IIA; 211 hips; 69 females/37 males) and dysplastic hip (DH; Graf IIB/IIC/III/D/IV; 21 hips; 8 females/3 males). One resident and one experienced radiologist reviewed ultrasonography images performed in the fourth week. To compare the groups, Student&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s t and Mann-Whitney tests for normally and non-normally distributed covariates were performed. Accuracy of PFD to diagnose DDH was calculated. Intraclass correlation coefficient (ICC) was calculated to assess inter-observer agreement. Mean PFDs of ND group were 3.09mm at neutral position and 3.64mm with the hip flexed. Mean PFDs of DH group were 6.29mm and 7.59mm, respectively. Sensitivity, specificity, and accuracy of PFD were 94.4%, 93.4%, and 97.2% (cut-off=4.6mm) at neutral position and 94.4%, 89.0%, and 95.5% (cut-off=4.9mm) with hip flexed. ICCs were 0.852 and 0.864, respectively. PFD is comparable with Graf method, enabling physicians to differentiate patients who should undergo treatment from those who should not. PFD can be used as a screening tool for diagnosing DDH with high accuracy, even by inexperienced radiologists.
The pathogenesis of endotoxemic tubular dysfunction with failure in urine concentration is poorly... more The pathogenesis of endotoxemic tubular dysfunction with failure in urine concentration is poorly understood. Urea plays an important role in the urinary concentrating mechanism and expression of the urea transporters UT-A1, UT-A2, UT-A3, UT-A4 and UT-B is essential for tubular urea reabsorption. The present study attempts to assess the regulation of renal urea transporters during severe inflammation in vivo. Materials and methods By agreement of the animal protection committee C57BL/6J, mice were injected with lipopolysaccharides (LPS, 10 mg/kg) or proinflammatory cytokines. Hemodynamic, renal parameters and the expression of renal urea transporters were investigated. To clarify the role of cytokines and renal ischemia in the regulation of renal urea transporters, experiments were performed with cytokine knockout mice, mice treated with low-dose LPS (1, 5 mg/kg) as a sepsis model without induction of hypotension, glucocorticoid-treated mice, and mice with renal artery clipping serving as a model for renal ischemia. Results and discussion LPS-injected mice (10 mg/kg) presented with reduced glomerular filtration rate, fractional urea excretion and inner medulla osmolality associated with a marked decrease in expression of UT-A1, UT-A2, UT-A3, UT-A4 and UT-B (Figure ). Similar alterations were observed after application of TNFα, IL-1β, IFNγ or IL-6. LPS-induced downregulation of urea transporters was not affected in knockout mice with deficient TNFα, IL-receptor-1, IFNγ or IL-6. Glucocorticoid treatment inhibited LPS-induced increases of tissue TNFα, IL-1β, IFNγ or IL-6 concentration, diminished LPS-induced renal dysfunction and attenuated the downregulation of renal urea transporters. Injection of low-dose LPS (1, 5 mg/kg) also led to renal dysfunction paralleled by a downregulation of renal urea transporters without alterations in blood pressure. Renal ischemia induced by renal artery clipping did not influence the expression of urea transporters. Conclusion Our findings demonstrate downregulation of renal urea transporters that probably accounts for tubular dysfunction during sepsis. Furthermore, they suggest that downregulation of Figure 1 (abstract P1) Effect of lipopolysaccharide (LPS) (10 mg/kg), dexamethasone (10 mg/kg) and the combination of both on UT-A1, UT-A2, UT-A3, UT-A4 and UT-B mRNA in the kidney 6, 12 and 24 hours after intraperitoneal injection. Values are related to signals obtained for β-actin mRNA and presented as the percentage of vehicle control. Mean ± SEM of six animals per group. *P < 0.05 versus control, # P < 0.05 versus LPS treatment. S2
Background and purpose: Sepsis is a systemic inflammatory response resulting from the inability o... more Background and purpose: Sepsis is a systemic inflammatory response resulting from the inability of the host to restrict local infection. The failure of neutrophil migration to the infection site is one of the mechanisms involved in this process. Recently, it was demonstrated that this event is mediated by nitric oxide (NO). The present study addresses the possibility that peroxynitrite (ONOO-), a NO-derived powerful oxidizing and nitrating compound, could also be involved in neutrophil migration failure. Experimental approach: Male C57Bl/6 mice were subjected to moderate (MSI) or severe (SSI) septic injury, both induced by cecal ligation and puncture (CLP). The leukocyte rolling and adhesion in the mesentery was evaluated by intravital microscopy. Cytokines (TNF-a and MIP-1a) were measured by ELISA and 3-nitrotyrosine (3-NT) by immunofluorescence. Key results: Compared with saline pretreatment of SSI mice, pre-treatment with uric acid, a ONOOscavenger, partially restored the failure of neutrophil rolling, adhesion and migration to the site of infection. These mice also presented low circulating bacterial counts and diminished systemic inflammatory response. Pretreatment with uric acid reduced 3-NT labelling in leukocytes in mesenteric tissues and in neutrophils obtained from peritoneal exudates. Finally, uric acid pretreatment enhanced significantly the survival rate in the SSI mice. Similarly, treatment with FeTPPs, a more specific ONOOscavenger, re-established neutrophil migration and increased mice survival rate. Conclusions and implications: These results indicate that ONOOcontributed to the reduction of neutrophil/endothelium interaction and the consequent failure of neutrophil migration into infection foci and hence susceptibility to severe sepsis.
Anais Principais do Simpósio Brasileiro de Computação Aplicada à Saúde (SBCAS 2020)
In an attempt to aid the subtyping of spondyloarthritis (SpA), this work assessed neural nets and... more In an attempt to aid the subtyping of spondyloarthritis (SpA), this work assessed neural nets and magnetic resonance imaging (MRI) features to predict SpA. Patients underwent SPAIR and STIR MRI sequences. Radiologists manually segmented sacroiliac joints images for extracting MRI features. A neural net used these features to predict SpA. The STIR-based model yielded higher performance than SPAIR to diagnose SpA, although no statistical difference was found between them. The SPAIR model yielded an area under the curve of 0.83 to differentiate axial and peripheral subtypes, while STIR yielded 0.57 (p < 0.05 on curves difference). Therefore, neural nets modeled with SPAIR-extracted features distinguished SpA using a single MRI exam of the sacroiliac joints.
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Papers by Vitor Dalto