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BACKGROUND: Magnetic resonance diffusion tensor imaging (DTI) has recently been used to evaluate the developing cartilage of children, but the influencing factors have not been well studied. OBJECTIVE: The objective of this study was to investigate the influence of the diffusion gradient strength (b value), diffusion gradient direction, age and sex on knee cartilage DTI in healthy children aged 6-12 years. MATERIALS AND METHODS: A total of 30 healthy child volunteers, with an average age of 8.9 ± 1.6 (mean ± standard deviation) years, were enrolled in this study. They were categorized into three groups according to their age range: 6-8 years, 8-10 years and 10-12 years, ensuring equal sex distribution in each group (5 boys and 5 girls). These volunteers underwent routine left knee joint magnetic resonance imaging (MRI) and serial DTI scans. DTI parameters were altered as follows: when b value = 600 s/mm2, diffusion gradient direction was set to 6, 15, 25, 35 and 45; and when diffusion gradient direction = 25, b value was set to 300, 600, 900 and 1200 s/mm2. The values of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were separately acquired using image post-processing techniques. The correlation between various b values, diffusion gradient directions, age and sex on the one hand and FA and ADC values on the other, was investigated. RESULTS: (1) When diffusion gradient direction was fixed and the b value was varied, both FA and ADC exhibited a decreasing trend as the b value increased (P < 0.001). (2) When the b value was fixed and diffusion gradient direction was varied, the FA of knee cartilage showed a decreasing trend with increasing diffusion gradient direction (P < 0.001). (3) The FA value increased with age (P < 0.05). CONCLUSION: The b value, diffusion gradient direction value and age exert a significant impact on both FA and ADC values in MR DTI of knee cartilage in children aged 6-12 years. In order to obtain a stable DTI, it is recommended to select a b value ≥ 600 s/mm2 and a diffusion gradient direction ≥ 25 during scanning.
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Cartilagem Articular , Imagem de Tensor de Difusão , Articulação do Joelho , Humanos , Criança , Masculino , Feminino , Imagem de Tensor de Difusão/métodos , Cartilagem Articular/diagnóstico por imagem , Estudos Prospectivos , Articulação do Joelho/diagnóstico por imagem , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: The shape of the labrum is strongly correlated with outcomes of developmental dysplasia of the hip (DDH). Magnetic resonance imaging (MRI) is the generally preferred imaging technique for observing the labrum. PURPOSE: We aimed to find a correlation between the labrum shape and anterior-posterior (AP) pelvic measurements in children with DDH. METHODS: Preoperative AP pelvic x-ray radiographs and MRI of patients with DDH from January 2019 to December 2021 were retrospectively collected and divided into three groups by labrum shape on MRI: everted, partly inverted, and inverted. The acetabular length ratio (RAL) in patients with unilateral DDH and the ratio of acetabular length to interpedicular distance (RALI) in all patients were calculated. T-tests were used to analyze differences between the groups. Receiver operating characteristic curve (ROC) analysis was performed between the everted group and the partly inverted and inverted groups. RESULTS: We found significant differences in RAL between the everted and partly inverted groups, everted and inverted groups, and everted and combined groups. The ROC analysis showed that the best cutoff value for RAL was 0.945 between the everted and combined groups, with an area under the curve (AUC) of 88.4%. The sensitivity at the best RAL value was 0.783, and the specificity was 0.887. Moreover, we observed a significant difference in RALI between the everted, partly inverted, and inverted groups, as well as between the everted and combined groups. The optimal cutoff value for RALI between the everted and combined groups was 0.575, with an AUC of 74.5%. The sensitivity at the best RALI value was 0.765, and the specificity was 0.674. CONCLUSION: The RAL or RALI values on pelvic AP radiographs can be used to predict the shape of the labrum. LEVEL OF EVIDENCE: III.
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Acetábulo , Displasia do Desenvolvimento do Quadril , Imageamento por Ressonância Magnética , Radiografia , Humanos , Estudos Retrospectivos , Feminino , Masculino , Displasia do Desenvolvimento do Quadril/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Acetábulo/diagnóstico por imagem , Radiografia/métodos , Lactente , Pré-Escolar , Curva ROCRESUMO
OBJECTIVES: To investigate the association of brain MRI and clinical variables with death in children with central nervous system involvement of hemophagocytic lymphohistiocytosis (CNS-HLH). METHODS: Clinical and brain MRI data of children with CNS-HLH from January 2012 to March 2022 were reviewed retrospectively. Patients were divided into the deceased group and the surviving group. The intergroup differences of seven brain MRI variables, twelve clinical variables, and underlying diseases were studied. RESULTS: One hundred and fourteen patients were included in this study, consisting of 59 who died and 55 who survived. The included clinical variables did not show statistically independent correlation with patients' deaths. For MRI variables, a multivariate analysis demonstrated restricted diffusion of lesion (OR = 9.64, 95% CI: 3.39-27.43, p < 0.001) and count of affected brain regions (CABR) (OR = 1.24, 95% CI: 1.03-1.49, p = 0.02) were independent risk factors for death. ROC curve showed CABR (AUC = 0.79, 95% CI: 0.70-0.87, p < 0.001) is highly predictive for mortality with an optimal cutoff value of 4.5 (sensitivity 76%, specificity 73%). For HLH subtypes, familial HLH (F-HLH, OR = 9.90, 95% CI: 2.01-48.87, p = 0.005) and immune-compromise-related HLH (IC-HLH, OR = 4.95, 95% CI: 1.40-17.46, p = 0.01) presented statistically stronger association with death than infection-related HLH. F-HLH and IC-HLH preferred to have large lesions, restricted diffusion, and more brain regions involved than other subtypes. CONCLUSION: Brain MRI features exhibit independent prediction for mortality in children with CNS-HLH, and HLH subtypes pose effects on patient outcomes and brain MRI findings. CLINICAL RELEVANCE STATEMENT: The number of affected brain regions and diffusion restriction of lesion exhibit significant correlation with mortality in children diagnosed with CNS-hemophagocytic lymphohistiocytosis, and may serve as candidate MRI markers for the prediction of the disorder's severity. KEY POINTS: ⢠The brain MRI markers, restricted diffusion of lesion and count of affected brain regions, significantly correlated with death. ⢠Familial and immune-compromise-related hemophagocytic lymphohistiocytosis presented statistically stronger association with death than infection-related subtype. ⢠Brain MRI is potential in death-predicting for children with central nervous system involvement of hemophagocytic lymphohistiocytosis.
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Linfo-Histiocitose Hemofagocítica , Humanos , Criança , Linfo-Histiocitose Hemofagocítica/diagnóstico por imagem , Linfo-Histiocitose Hemofagocítica/complicações , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Fatores de RiscoRESUMO
BACKGROUND: Computed tomography (CT) can be used for the early detection of lymphadenitis. Radiomics is able to identify a large amount of hidden information from images. However, few CT-based radiomics studies on cervical lymphadenitis in children have been published. OBJECTIVE: This study aimed to investigate the role of visual CT analysis and CT radiomics in differentiating cervical suppurative node necrosis from tuberculous node necrosis in pediatric patients. MATERIALS AND METHODS: A total of 101 patients with cervical suppurative lymphadenitis (n=52) or cervical tuberculous lymphadenitis (n=49) were included. Clinical data and CT images were retrieved for analysis. For visual observation, 11 major CT features were identified for univariate and multivariate analyses. For radiomics analysis, image segmentation, feature value extraction, and dimension reduction, feature selection and the construction of radiomics-based models were performed through the RadCloud platform. RESULTS: For the visual observation, significant differences were found between the two groups, including the short diameter of the largest necrotic lymph node (P=0.03), sharp border of the node (P=0.02), fusion of nodes (P=0.02), regular silhouette of the necrotic area (P=0.001), multilocular necrotic area (P=0.02), node calcification (P=0.004), and enhancement degree of the nodal nonnecrotic area (P=0.01). No feature was found to be an independent predictor for suppurative or tuberculous lymphadenitis (P>0.05 for all features). Concerning the radiomics analysis, after feature value extraction and dimension reduction, nine related features were selected. The support vector machine classifier achieved high diagnostic performance in distinguishing suppurative from tuberculous lymphadenitis. The area under the curve, accuracy, sensitivity, and specificity of the support vector machine model test set were 0.89 (95% confidence interval: 0.72-1.00), 0.88, 0.78, and 0.90, respectively. CONCLUSION: Compared to observer-based CT image analyses, radiomics model-based CT image analyses exhibit better performance in the differential diagnosis of cervical suppurative and tuberculous lymphadenitis complicated with nodal necrosis in children.
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Linfadenite , Tuberculose dos Linfonodos , Humanos , Criança , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Tuberculose dos Linfonodos/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Linfadenite/diagnóstico por imagem , Linfadenite/patologia , Necrose/diagnóstico por imagem , Necrose/patologia , Estudos RetrospectivosRESUMO
PURPOSE: Hip vessel examination provides key information on many hip-related pediatric diseases, and it has an important role in the evaluation of femoral head (FH) blood supply and diagnosis of avascular necrosis (AVN). The aim of this study was to investigate the feasibility of MR-enhanced high-resolution three-dimensional water-selective cartilage (3D-WATSc) sequence in visualizing the vessels of the hip joint in children. PATIENTS AND METHODS: Children with hip disease were randomly enrolled prospectively at our hospital from January 2021 to August 2022. We performed our institution's hip MRI protocol and enhanced high-resolution 3D-WATSc sequence. The 3D-WATSc images were reconstructed and analyzed, and images of the normal hip were categorized into grades 0-3. The abnormal hip images were compared with those of the normal side using the χ2 test. RESULTS: Twenty-four patients with unilateral hip abnormalities were included in this study. The cartilaginous vascular canal and ossification centre vessels of normal FHs were observed in 18 patients (75%) and met the grade 3 standard. An abnormal cartilaginous canal was observed in 16 patients (67%); meanwhile, 18 patients (75%) had abnormal extrachondral vessels. Comparison of high-resolution 3D-WATSc images with those of the normal side provided effective abnormal vascular information in 95.8% of patients. CONCLUSIONS: Enhanced high-resolution 3D-WATSc can visualize the blood vessels of the hip in children. This may provide a new method for the vascular study of various pediatric hip diseases.
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OBJECTIVE: This meta-analysis was carried out for assessing the accuracy of intravoxel incoherent motion (IVIM) parameters true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) in differentiating low-grade gliomas (LGGs) from high-grade gliomas (HGGs). METHODS: Literatures concerning IVIM in the grading of brain gliomas published prior to October 20, 2020, searched in the Embase, PubMed, and Cochrane library. Use the quality assessment of diagnostic accuracy studies 2 (QUADAS 2) to evaluate the quality of studies. We estimated the pooled sensitivity, specificity, and the area under the summary ROC (SROC) curve to identification the accuracy of IVIM parameters D, D*, and f evaluation in grading gliomas. RESULTS: Totally, 6 articles including 252 brain gliomas conform to the inclusion criteria. The pooled sensitivity of parameters D, D*, and f derived from IVIM were 0.85 (95%Cl, 0.76-0.91), 0.78 (95%Cl, 0.71-0.85), and 0.89 (95%Cl, 0.76-0.96), respectively. The pooled specificity were 0.78 (95%Cl, 0.60-0.90), 0.68 (95%Cl, 0.56-0.79), and 0.88 (95%Cl, 0.76-0.94), respectively. Meanwhile, the AUC of SROC curve were 0.89 (95%Cl, 0.86-0.92) , 0.81 (95%Cl, 0.77-0.84), and 0.94 (95%Cl, 0.92-0.96), respectively. CONCLUSION: This meta-analysis suggested that IVIM parameters D, D*, and f have moderate or high diagnosis value accuracy in differentiating HGGs from LGGs, and the parameter f has greater sensitivity and specificity. Standardized methodology is warranted to guide the use of this method for clinical decision-making. However, more clinical studies are needed to prove our view. ADVANCES IN KNOWLEDGE: IVIM parameter f showed greater sensitivity and specificity, as well as excellent performance than parameter D* and D.
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Neoplasias Encefálicas/diagnóstico por imagem , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Microcirculação , Área Sob a Curva , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Intervalos de Confiança , Imagem de Difusão por Ressonância Magnética , Glioma/irrigação sanguínea , Glioma/patologia , Humanos , Gradação de Tumores , Razão de Chances , Viés de Publicação , Sensibilidade e EspecificidadeRESUMO
CONTEXT: Soft tissue calcifications (STCs) were incidentally found in some of the Hymenoptera-stung (HS) children when they underwent computed tomography (CT) scans for evaluating complications of vital organs. Afterwards, a predilection of STCs to the children with severe complications was clinically noticed. A hypothesis was then developed that STCs secondary to HS may correlate with poor outcomes. OBJECTIVE: This study aims to firstly characterize the CT findings of STCs in HS children and to confirm our hypothesis that the occurrence of STCs may act as an indicator of poor outcomes in HS children. MATERIALS AND METHODS: Children who received CT scanning after Hymenoptera sting from January 2011 to October 2016 in our hospital were analyzed retrospectively. Shape, location, and distribution of the STCs were described according to the CT findings. Then the enrolled cases were classified into Soft Tissue Calcification Group (STCG) and non-Soft tissue Calcification Group (non-STCG) to conduct prognostic comparisons of Sequential Organ Failure Assessment (SOFA) scores, incidence of main complications (acute liver failure (ALF), acute kidney injury stage III (AKI-III) and multiple organ failure (MOF)), length of hospital days, and in-hospital death, respectively. Pearson correlation was also utilized between the cumulative volume of STCs and the SOFA score. RESULTS: Sixteen cases were enrolled, and STCs' incidence was 56.25% (9/16). Two STCG cases had diffuse nodular calcifications in their swollen subcutaneous tissue, and another seven had symmetrically stripy or patchy calcifications within or along local muscles. The SOFA scores during the first 3 days were all higher in STCG, and rose to the greatest difference at the third day (9.78 ± 2.17 vs. 2.29 ± 2.06, t = 7.009, p < .001); the incidence of ALF, AKI-III and MOF were significantly higher in STCG (66.67% vs. 0, p = .011), (77.78% vs. 0, p = .003) and (77.78% vs. 14.29%, p = .041); and children in STCG were treated with longer hospital durations (26.33 ± 8.41 days vs. 12.29 ± 7.36 days, t = 3.493, p = .004). One child in STCG died of cardiopulmonary failure, and no deaths occurred in non-STCG. No significant correlations presented between STCs cumulative volumes and SOFA score (rDay1 = 0.096, p = .806; rDay2 = 0.067, p = .863; rDay3 = 0.024, p = .950). CONCLUSION: Soft tissue calcifications detected on CT imaging following multiple Hymenoptera stings in pediatric patients may be a potential prognostic indicator of more severe complications and poorer outcomes.