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Studies using quantitative computed tomography (QCT) and data-driven image analysis techniques have shown that trabecular and cortical volumetric bone mineral density (vBMD) can improve the hip fracture prediction of dual-energy X-ray absorptiometry areal BMD (aBMD). Here, we hypothesize that (1) QCT imaging features of shape, density and structure derived from data-driven image analysis techniques can improve the hip fracture discrimination of classification models based on mean femoral neck aBMD (Neck.aBMD), and (2) that data-driven cortical bone thickness (Ct.Th) features can improve the hip fracture discrimination of vBMD models. We tested our hypotheses using statistical multi-parametric modeling (SMPM) in a QCT study of acute hip fracture of 50 controls and 93 fragility fracture cases. SMPM was used to extract features of shape, vBMD, Ct.Th, cortical vBMD, and vBMD in a layer adjacent to the endosteal surface to develop hip fracture classification models with machine learning logistic LASSO. The performance of these classification models was evaluated in two aspects: (1) their hip fracture classification capability without Neck.aBMD, and (2) their capability to improve the hip fracture classification of the Neck.aBMD model. Assessments were done with 10-fold cross-validation, areas under the receiver operating characteristic curve (AUCs), differences of AUCs, and the integrated discrimination improvement (IDI) index. All LASSO models including SMPM-vBMD features, and the majority of models including SMPM-Ct.Th features performed significantly better than the Neck.aBMD model; and all SMPM features significantly improved the hip fracture discrimination of the Neck.aBMD model (Hypothesis 1). An interesting finding was that SMPM-features of vBMD also captured Ct.Th patterns, potentially explaining the superior classification performance of models based on SMPM-vBMD features (Hypothesis 2). Age, height and weight had a small impact on model performances, and the model of shape, vBMD and Ct.Th consistently yielded better performances than the Neck.aBMD models. Results of this study clearly support the relevance of bone density and quality on the assessment of hip fracture, and demonstrate their potential on patient and healthcare cost benefits.

Background/Objective: This study is a case–control study to explore risk and protective factors, including clinical data and bone mineral density (BMD), affecting vertebral body fragility fracture in elderly men and postmenopausal women. In addition, we investigate the effectiveness of lumbar spine BMD by quantitative computed tomography (QCT) in discriminating vertebral fragility fracture. Methods: In this case–control study, 52 males and 198 females with vertebral fragility fracture were compared with sex- and age-matched healthy controls to analyse the risk factors that may affect vertebral fragility fracture. The L1–L3 vertebral BMDs were measured by QCT. The difference in risk factors between fracture cases and controls were analysed using student t test and Mann–Whitney U test. The correlation between BMD, age, height and weight were analysed using univariate analysis. Multiple logistic regression analysis was used to study statistically significant indexes. The receiver operating characteristic curve was used to calculate the cut-off values for positive and negative predictive values of BMD for vertebral fracture discrimination. Results: In males, body weight and BMD were significantly different between the fracture group and the control group, whereas BMD was only weakly correlated with age (r = −0.234). In females, only BMD was significantly different between the fracture and control groups. BMD was weakly correlated with height (r = 0.133) and weight (r = 0.120) and was moderately correlated with age (r = −0.387). There was no correlation between BMD and the remaining variables in this study. In both men and women, the BMD (p = 0.000) was the independent protective factor against vertebral fracture. The cut-off values of vertebral BMD for fractures were 64.16 mg/cm3 for males and 55.58 mg/cm3 for females. QCT-measured BMD has a high positive predictive value and negative predictive value for discriminating vertebral fragility fracture across a range of BMD values. Conclusion: This study suggests that BMD is closely related to vertebral fragility fracture and that QCT is an effective technique to accurately discriminate vertebral fragility fracture. The translational potential of this article: The spine BMD measured by QCT is closely related to fracture, which may allow clinicians to more accurately discriminate which individuals are likely to experience vertebral fragility fracture. Keywords: Bone mineral density, Quantitative computed tomography, Vertebral fragility fracture

In elderly subjects and in particular in those with osteoporosis the evidence on age related volume changes of the hip is still very limited. Even less is known about bone changes of the femoral head. The aim of this study is to explore associations of bone size of the femoral head and neck with age in postmenopausal women with very high risk of hip fracture and to investigate associations of femoral head and neck bone mineral density. MIAF (medical image analysis framework)-Femur was used for the analysis of CT datasets from 319 females with acute hip fractures age 50 to 98. Integral BMD and volume of the head and neck were assessed. The femoral head was divided into four quadrants to address differential vBMD and volume responses of its superior, inferior, posterior and anterior parts. Areal BMD (aBMD) of femoral neck was also obtained. In this population of postmenopausal women we did not observe age-related changes in bone volume of the femoral head or neck between ages 50 and 98 years. Integral vBMD in the head in the 90–98 year group was 48.0 mg/cm3 lower than that in 50–59 year group, which accounts for nearly 30% decrease in vBMD with 40 years increase. Age-related vBMD changes in the head quadrants were similar to that in total. With age, the trend line correlation coefficients for vBMD in quadrants were relatively small, but significant (p

Background and Purpose: Muscle weakness and bone fragility are both associated with hip fracture. In general, muscle contractions create forces to the bone, and bone strength adapts to mechanical loading through changes in bone architecture and mass. However, the relationship between impairment of muscle and bone function remain unclear. In particular, the associations of muscle with properties of proximal femur cortical and trabecular bone are still not well understood. The aim of this study was to explore the associations of hip/thigh muscle density (CT attenuation value in Hounsfield units) and size with cortical and trabecular bone mineral density (BMD) of the proximal femur. Materials and Methods: Three-dimensional quantitative computed tomography (QCT) imaging of the lumber, hip and mid-thigh was performed in a total of 301 participants (mean age 68.4 ± 6.1 years, 194 women and 107 men) to derive areal BMD (aBMD) and volumetric BMD (vBMD). Handgrip strength (HGS) and the Timed Up and Go (TUG) test were also performed. From the CT images, cross-sectional area (CSA), and density were determined for the gluteus maximus muscle (G.MaxM), trunk muscle at the vertebrae L2 level, and mid-thigh muscle. Multivariate generalized linear models were applied to assess associations. Results: Total hip (TH) aBMD was associated significantly with G.MaxM CSA (men: P = 0.042; women: P < 0.001) and density (men: P = 0.012; women: P = 0.043). In women, 0.035 cm2 of mid-thigh CSA (95% CI, 0.014–0.057; P = 0.002) increased per SD increase in TH aBMD, but this significance was not observed in men (P = 0.095). Trunk muscle density and CSA were not associated with proximal femur BMD. The associations of hip/thigh muscle parameters with femoral neck BMD were weaker than those with trochanter and intertrochanter BMD. Furthermore, compared to muscle density, muscle CSA showed better associations with vBMD. G.MaxM CSA was associated with trochanter (TR) Cort. vBMD in men (β, 19.898; 95% CI, 0.924–38.871; P = 0.040) and in women (β, 15.426; 95% CI, 0.893–29.958; P = 0.038). Handgrip strength was only associated with TR aBMD (β, 0.038; 95% CI, 0.006–0.070; P = 0.019) and intertrochanter aBMD (β, 0.049; 95% CI, 0.009–0.090; P = 0.016) in men. Conclusions: We observed positive associations of the gluteus and thigh muscle size with proximal femur volumetric BMD. Specifically, the gluteus maximus muscle CSA was associated with trochanter cortical vBMD in both men and women.

Objective To investigate the correlation between non-alcoholic fatty liver disease and visceral adipose tissue in non-obese Chinese adults using computed tomography (CT). Materials and Methods The study included 454 subjects undergoing abdominal CT scan. Degree of CT attenuation in liver and spleen, and the degree of fat infiltration in liver were evaluated according to three indices: the attenuation value of liver parenchyma (CTLP), the attenuation ratio of liver and spleen (LSratio) and the attenuation difference between liver and spleen (LSdif). Visceral fat area (VFA) and total fat area (TFA) at L2/3 and L4/5 levels were measured, and the abdominal subcutaneous fat area (SFA) was calculated. Bivariate correlation analysis was carried out to determine the correlation among these factors. Results In men, VFA, SFA and TFA at L2/3 and L4/5 levels showed significant differences in terms of the three indices to distinguish fatty liver from non-fatty liver (all, p < 0.001). In men, all the three indices showed negative correlation with TFA, SFA and VFA (all, p < 0.001). The negative correlation between the three indices and VFA at the L2/3 level was higher than at L4/5 level (r = -0.476 vs. r = -0.340 for CTLP, r = -0.502 vs. r = -0.413 for LSratio, r = -0.543 vs. r = -0.422 for LSdif, p < 0.001, respectively). The negative correlation between LSratio, LSdif and VFA at L2/3 and L4/5 levels was higher than SFA at the corresponding level. In women, all the three indices showed negative correlation with VFA and TFA at L2/3 and L4/5 levels, and the negative correlation between CTLP and VFA was higher at L2/3 level than at L4/5 level (r = -0.294 vs. r = -0.254, p < 0.001). Conclusion In non-obese Chinese adults, the degree of hepatic fatty infiltration showed a strong correlation with abdominal fat on CT. VFA at L2/3 level was more closely related to fatty liver compared with VFA at L4/5 level.

summary Objectives: To investigate the change in cartilage T2 values and structural degeneration in knee joints over 72 months in women of African American (AA) vs Caucasian American (CA) ethnicity. Methods: Knee 3T magnetic resonance imaging (MRIs) from baseline, 24, 48 and 72 months visits of 100 AA and 100 CA women from the Osteoarthritis Initiative (OAI) were assessed for cartilage T2 values and whole-organ magnetic resonance imaging (WORMS) score. Subjects were pair-matched by age, body mass index (BMI), KellgreneLawrence (KL) score, clinical site and subcohort within the OAI. We compared the rate of change in whole knee cartilage T2 values and WORMS cartilage, bone marrow edema pattern (BMEP) and meniscus scores between the two ethnic groups using mixed random effects models. Results: At 24 and 48 months 60 subjects and at 72 months 45 subjects per group were available for analysis resulting in 38 complete pairs with data of all time points. Compared to CA, cartilage T2 values in AA increased at a significantly faster rate at baseline (AA: 0.45 ms/y, CA: 0.35 ms/y, P ¼ 0.029) and averaged over 6 years (AA: 0.36 ms/y, CA: 0.27 ms/y, P ¼ 0.039) with changes in both groups reaching a plateau by 48 months. Cartilage, meniscus and BMEP scores tended to increase in both groups during follow up, but rates of change did not differ by ethnicity. Conclusion: Cartilage T2 values increased faster over 72 months in AA than CA, however changes in WORMS cartilage, meniscus and BMEP scores did not differ. T2 values may be able to distinguish ethnicity-related differences of cartilage degeneration at an early stage before differences in structural joint degeneration appear.

Objective: The objective of this study was to evaluate the usefulness of T2 high signal intensity (T2-HSI) and decreased anteroposterior diameter (APD), diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) in evaluating postoperative cervical cord function. Methods: The study included 57 postoperative cervical spondylotic myelopathy patients. Clinical evaluation and functional recovery assessments were performed using the modified Japanese Orthopaedic Association (mJOA) score and recovery rate. The presence of T2-HSI and decreased APD was recorded for exploring the relevance. Spearman correlation was applied to investigate the relationships between DTI and NODDI metrics and mJOA score. Multiple comparisons of T2 signal intensity, APD and diffusion metrics were evaluated by using multiple linear regression. Results: Only the recovery rate was significantly different between T2-HSI and non-T2-HSI (nT2-HSI) patients (χ2 = 4.466, p = 0.045). Significant differences were not observed between cervical cords with and without decreased APD. Diffusion metrics, including fractional anisotropy (p = 0.0005), mean diffusivity (p = 0.0008), radial diffusivity (p = 0.0003) and intracellular volume fraction (p = 0.001), were significantly correlated with mJOA score. The ability of T2 signal intensity (p = 0.421) and APD (p = 0.420) to evaluate the postoperative function was inferior to that of fractional anisotropy (p = 0.002), mean diffusivity (p = 0.001), radial diffusivity (p = 0.001) and intracellular volume fraction (p = 0.004). Conclusion: Conventional magnetic resonance imaging signs could be considered as a reference to make an approximate assessment, whereas DTI and NODDI could be better quantitative tools for evaluating the postoperative function and may help in interpreting residual symptoms. The translational potential of this article: DTI and NODDI could provide reliable postoperative evaluation and analysis for cervical spondylotic myelopathy patients. Keywords: Anteroposterior diameter, Cervical spondylotic myelopathy, Diffusion tensor imaging, Neurite orientation dispersion and density imaging, T2 high signal intensity

The purpose of this study was to investigate the abnormality of language networks in left medial temporal lobe epilepsy (MTLE) using fMRI.Eight patients with left MTLE and 15 healthy subjects were evaluated. An auditory semantic judgment (AJ) paradigm was used. The fMRI data were collected on a 3T MR system and analyzed by AFNI (analysis of functional neuroimages) to generate the activation map.Behavioral data showed that the reaction time of the left MTLE patients was significantly longer than that of controls on the AJ task (t=-3.396, P0.05). The left MTLE patients also exhibited diffusively decreased activation in the AJ task. Right hemisphere dominance of Broca's and Wernicke's areas was demonstrated in left MTLE patients.Long-term activation of spikes in left MTLE patients results in language impairment, which is associated with an abnormality of the brain neural network.

Epidermoid cysts are congenital tumors, whose typical imaging presentations are characterized by low density on CT, low signal intensity on T1-weighted images and high signal intensity on proton density- and T2-weighted images. Coexistence of two intracranial epidermoid cysts with different MR presentations is very rare. Here, we report a case of multiple epidermoid cysts with typical and atypical MR presentations.

The purpose of this study was to investigate the features of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in cortical tubers and white-matter lesions in patients with tuberous sclerosis (TS) using diffusion tensor imaging (DTI).Conventional magnetic resonance imaging (MRI) and DTI were performed in 14 patients with clinically established TS. Based on these DT images, ADC and FA maps were generated. The ADC values in 32 cortical tubers, and the ADC and FA values in 18 white-matter lesions were measured and compared with those of the corresponding contralateral regions.Compared with the corresponding contralateral regions, cortical tubers of TS patients had significantly higher ADC values (P0.001); white-matter lesions had significantly higher ADC values (P0.001) and significantly lower FA values (P0.001).DTI is a useful tool for demonstrating changes in cortical tubers and white-matter lesions resulting from TS.

Purpose The purpose of this study was to analyze whole-brain white matter changes in medial temporal lobe epilepsy (MTLE). Materials and methods We studied 23 patients with MTLE and 13 age- and sex-matched healthy control subjects using voxel-based morphometry (VBM) on T1-weighted 3D datasets. The seizure focus was right sided in 11 patients and left sided in 12. The data were collected on a 1.5 T MR system and analyzed by SPM 99 to generate white matter density maps. Results Voxel-based morphometry revealed diffusively reduced white matter in MTLE prominently including bilateral frontal lobes, bilateral temporal lobes and corpus callosum. White matter reduction was also found in the bilateral cerebellar hemispheres in the left MTLE group. Conclusion VBM is a simple and automated approach that is able to identify diffuse whole-brain white matter reduction in MTLE.

Purpose The purpose of this study was to characterize gliomatosis cerebri on magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS), and to analyze the value of these two techniques in diagnosis and differential diagnosis of gliomatosis cerebri. Materials and methods MR images of 14 patients with gliomatosis cerebri were reviewed retrospectively; seven of the patients also underwent MRS (single-voxel point-resolved spectroscopy, and chemical-shift imaging point-resolved spectroscopy). Tumorous were confirmed by surgery and biopsy. The distribution, extension and signal features of lesions were assessed, and the MR spectroscopy results were analyzed. Results Tumors involved at least two lobes of the brain in all patients. Widespread invasion with isointensity or hypointensity on T1-weighted MR images and hyperintensity on T2-weighted images were found while no prominent necrosis, hemorrhage or contrast enhancement was found. All patients who underwent MRS showed elevated Cho/Cr and Cho/NAA levels as well as decreased NAA/Cr ratios in the abnormal areas on T2-weighted images, three of which showed a lactate doublet. Anaplastic lesions had higher Cho/NAA levels in three cases. Abnormality of metabolism was also seen in the margin of the lesion that was normal on T2-weighted images. Conclusion MRI and MRS are valuable techniques for diagnosis and differential diagnosis of gliomatosis cerebri. Combining clinical information and MRI findings, as well as MRS, is crucial for making a definitive diagnosis.