ObjectiveTo investigate the value of CT-based radiomics and clinical data in predicting the efficacy of non-vascularized bone grafting (NVBG) in hip preservation, and to construct a visual, quantifiable, and effective method for decision-making of hip preservation. Methods Between June 2009 and June 2019, 153 patients (182 hips) with osteonecrosis of the femoral head (ONFH) who underwent NVBG for hip preservation were included, and the training and testing sets were divided in a 7∶3 ratio to define hip preservation success or failure according to the 3-year postoperative follow-up. The radiomic features of the region of interest in the CT images were extracted, and the radiomics-scores were calculated by the linear weighting and coefficients of the radiomic features after dimensionality reduction. The clinical predictors were screened using univariate and multivariate Cox regression analysis. The radiomics model, clinical model, and clinical-radiomics (C-R) model were constructed respectively. Their predictive performance for the efficacy of hip preservation was compared in the training and testing sets, with evaluation indexes including area under the curve, C-Index, sensitivity, specificity, and calibration curve, etc. The best model was visualised using nomogram, and its clinical utility was assessed by decision curves. ResultsAt the 3-year postoperative follow-up, the cumulative survival rate of hip preservation was 70.33%. Continued exposure to risk factors postoperative and Japanese Investigation Committee (JIC) staging were clinical predictors of the efficacy of hip preservation, and 13 radiomic features derived from least absolute shrinkage and selection operator downscaling were used to calculate Rad-scores. The C-R model outperformed both the clinical and radiomics models in predicting the efficacy of hip preservation 1, 2, 3 years postoperative in both the training and testing sets (P<0.05), with good agreement between the predicted and observed values. A nomogram constructed based on the C-R model showed that patients with lower Rad-scores, no further postoperative exposure to risk factors, and B or C1 types of JIC staging had a higher probability of femoral survival at 1, 2, 3 years postoperatively. The decision curve analysis showed that the C-R model had a higher total net benefit than both the clinical and radiomics models with a single predictor, and it could bring more net benefit to patients within a larger probability threshold. Conclusion The prediction model and nomogram constructed by CT-based radiomics combined with clinical data is a visual, quantifiable, and effective method for decision-making of hip preservation, which can predict the efficacy of NVBG before surgery and has a high value of clinical application.
We reported a 59-year-old male with exertional angina pectoris, and the coronary angiography showed multiple vessel lesions. The initial strategy was coronary artery bypass grafting (CABG). The measurement of quantitative flow ration (QFR) before operation indicated that the posterior descending branch (PD) did not need to be treated. The left circumflex branch (LCX) was small, and the QFR of the left anterior descending branch (LAD) and the first diagonal branch (D1) was<0.8. Therefore, the LAD and D1 were re-vascularized. The operation strategy was changed to on-pump CABG through a small incision, and the final strategy was LIMA-D1-LAD (sequential), fractional flow reserve (FFR) of distal LAD and D1 after CABG were>0.8 by computed tomography FFR. SYNTAX scores after CABG were 20 and the functional SYNTAX scores after CABG were 3, indicating a good prognosis.
Objective To investigate the gene expression of beta-defensin-4 (mBD-4) and mBD-6 in acute lung injury (ALI) mouse.Methods Sixty adult mice were randomly divided into a control group and a ALI group.ALI was induced by intraperitoneal injection of lipopolysaccharide (LPS) in the ALI group.The control group was treated with same dose of normal saline.The lung tissues were harvested at different time point after stimulation.The expression of mBD-4 and mBD-6 mRNA was measured by real-time quantitative reverse transcription polymerase chain reaction.DNA sequencing was used to confirm the specificity of mBD-4 and mBD-6 cDNA fragment.Results There were no obvious mBD-4 and mBD-6 mRNA expression in mouse lung in the control group at all time points and ALI 6 h group.In the ALI group a marked increasing expression was found on 12 h，1 d and 3 d after LPS stimulation.The mBD-4 mRNA expression was significant higher in the ALI groups of 1 d and 3 d points than that of ALI 12 h group with no obvious difference between each other.There were no significant differences of mBD-6 mRNA expression between ALI groups of 12 h，1 d and 3 d points Conclusion mBD-4 and mBD-6 mRNA is not constitutive expressed in mouse lung and show a up-regulative expression pattern after ALI.
Histological studies and morphometry quantitative analysis have been performed on trial rabbit’s dilated common bile duct(CBD),which does not dilate simultaneously.The results shows:①Epithelia of rabbit’s CBD have a ber reparable function,which is fairly significant to the prevention of bile duct’s further injure under the pathogenic situation.②The smooth muscle cell(SMC)of the CBD is the histological basis of contraction,some SMC can be seen in contracting state under light microscope.This indicates that the SMC in rabbit’s CBD possess contracting function.③The collagenous and elastic fibers have the normal histological morphometric characteristics and quantity in it’s dilatation process,and no breekdown and degeneration of the fibers can be detected.Because of the morphological structure of these sections is quite similiar with normal ones,theoretically,we suspect that when pathological change of bile duct’s distal portion is relieved and the bile pressure is normal again.It is possible for this dilating bile duct to return to its formal shape and size.
Takayasu arteritis (TA) is a chronic nonspecific inflammation that commonly occurs in the aorta and its main branches. Most patients with TA are lack of clinical manifestations, leading to misdiagnosis. When the TA is correctly diagnosed, the patients may already have stenosis or occlusion in the involved arteries, resulting in arterial ischemia and hypoxia symptoms, and in severe cases it will be life-threatening. Contrast-enhanced ultrasonography (CEUS) is an emerging method for assessing TA, but the assessment relies heavily on experiences of radiologists performing manual and qualitative analyses, so the diagnostic results are often not accurate. To overcome this limitation, this paper presents a computer-assisted quantitative analysis of TA carotid artery lesions based on CEUS. First, the TA lesion was outlined on the carotid wall, and one homogeneous rectangle and one polygon were selected as two reference regions in the carotid lumen. The temporal and spatial features of the lesion region and the reference regions were then calculated. Furthermore, the difference and ratio of the features between the lesion and the reference regions were computed as new features (to eliminate interference factors). Finally, the correlation was analyzed between the CEUS features and inflammation biomarkers consisting of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). The data in this paper were collected from 34 TA patients in Zhongshan Hospital undergoing CEUS examination with a total of thirty-seven carotid lesions, where two patients were with two lesions before and after treatment and one patient was with left and right bilateral lesions. Among these patients, 13 were untreated primary patients with a total of 14 lesions, where one patient was with bilateral lesions. The results showed that for all patients, the neovascularization area ratio in the 1/3 inner region of a lesion (ARi1/3) achieved a correlation coefficient (r) of 0.56 (P=0.001) with CRP, and for the primary patients, the neovascularization area ratio in the 1/2 inner region of a lesion (ARi1/2) had an r-value of 0.76 (P=0.001) with CRP. This study indicates that the proposed computer-assisted method can objectively and semi-automatically extract quantitative features from CEUS images, so as to reduce the effect on diagnosis due to subjective experiences of the radiologists, and thus it is expected to be used for clinical diagnosis and severity evaluation of TA carotid lesions.
ObjectiveTo explore the application value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) quantitative parameters and apparent diffusion coefficient (ADC) value in evaluating the differentiation degrees and T stages of rectal cancer.MethodsThe patients with rectal cancer from November 2017 to November 2019 in the Sichuan Provincial People’s Hospital were collected. The volume transfer constant (Ktrans), flux rate constant (Kep), and extravascular extracellular volume fraction (Ve), and ADC values of the tumors were measured and compared in the patients with the different differentiation degrees and T stages. The receiver operating characteristic (ROC) curve analysis was performed.ResultsAll of 53 eligible patients were included, including 13 cases of high differentiation, 30 cases of medium differentiation, and 10 cases of low differentiation; 5 cases of T1 stage, 8 cases of T2 stage, 24 cases of T3 stage, and 16 cases of T4 stage. ① There were statistical differences in the Ktrans and ADC values among the different differentiation degrees of rectal cancer (P=0.004, P<0.001), and no statistical differences in the Kep and Ve values (P>0.050) among them. The Ktrans value was increased with decreased differentiation degree (P<0.050), the ADC value was decreased with decreased differentiation degrees (P<0.050). ② There were statistical differences in the Ktrans and ADC values among the different T stages of rectal cancer (P=0.002; P=0.007), and no statistical differences in the Kep and Ve values (P>0.050) among them. The Ktrans and ADC values were statistically different between the T2 and T3 stages of rectal cancer (P=0.009, P=0.013). ③ The Ktrans and ADC values could distinguish the high and medium differentiation degrees of rectal cancer, its area under ROC curve (AUC) values were 0.677 and 0.763, respectively, and the corresponding best thresholds were 0.180/min and 1.179 mm2/s; The Ktrans and ADC values could distinguish the medium and low differentiation degrees of rectal cancer, its AUC values were 0.693 and 0.967, and the corresponding best thresholds were 0.281/min and 0.906 mm2/s; The Ktrans and ADC values could distinguish the T2 and T3 stages of rectal cancer, its AUC values were 0.862 and 0.742, and the corresponding best thresholds were 0.204/min and 1.579 mm2/s.ConclusionDCE-MRI quantitative parameters and ADC value before surgery to determine the different differentiation degrees and T stages of rectal cancer have certain reference value, the best Ktrans and ADC thresholds to distinguish different differentiation degrees and T2 to T3 stages can be obtained through statistical analysis.
The new mechanisms of automaticity controlled by the calcium and membrane clocks in sinoatrial node are helpful to revealing the sinus arrhythmia, but the present calcium dynamic model is only on the single cell level. In the present study, a central and peripheral single cell model was developed, and by exponentially changing the cell membrane capacitance, size, conductance and gap junction from the center to the periphery, a two-dimensional inhomogeneous sinus and atrial model was created on the basis of the anatomical structure. Five-point difference and finite element methods were used to process the internal grids and the borders. Irregular borders were defined by creating segment trial functions. Quantitative experiments suggested the consistency of the central and peripheral action potentials with related reports in amplitude, cycle length, maximum diastolic potential and upstroke velocity. Functions of the calcium and membrane clocks on the leading pacemaker site and upstroke velocity as well as the effects of the atrial premature beat on the sinus automaticity were also in good agreement with those in other studies. The developed model is helpful for deeply studying relative roles of the calcium and membrane clocks in automaticity and the relations with electrical activities in atrium. At the same time it will lay the foundation for building three-dimensional sinus and atrial organic models.
To assess the background field removal method usually used in quantitative susceptibility mapping (QSM), and to analyze the cause of serious artifacts generated in the truncated k-space division (TKD) method, this paper discusses a variety of background field removal methods and proposes an improved method to suppress the artifacts of susceptibility inversion. Firstly, we scanned phase images with the gradient echo sequence and then compared the quality and the speed of reconstructed images of sophisticated harmonic artifact reduction for phase data (SHARP), regularization enable of SHARP (RESHARP) and laplacian boundary value (LBV) methods. Secondly, we analyzed the reasons for reconstruction artifacts caused by the multiple truncations and discontinuity of the TKD method, and an improved TKD method was proposed by increasing threshold truncation range and improving data continuity. Finally, the result of susceptibility inversion from the improved and original TKD method was compared. The results show that the reconstruction of SHARP and RESHARP are very fast, but SHARP reconstruction artifacts are serious and the reconstruction precision is not high and implementation of RESHARP is complicated. The reconstruction speed of LBV method is slow, but the detail of the reconstructed image is prominent and the precision is high. In the QSM inversion methods, the reconstruction artifact of the original TKD method is serious, while the improved method obtains good artifact suppression image and good inversion result of artifact regions.
Objective To scientifically evaluate the nosocomial infection prevention and control ability of respiratory infectious diseases in general hospitals, and to construct a set of quantitative assessment system for the prevention and control ability of respiratory infectious diseases in general hospitals. Methods Papers, standards and guidelines online related to respiratory hospital infections published between January 1, 2010 and December 31, 2023 were selected, and infection control experience was summarized to build a pool of evaluation pionts. Then, this study used experts consultation to select the evaluation pionts, to calculate the weight coefficient and reached a consensus on the quantitative evaluation methods of each evaluation point. Results A total of 27 articles were included. The evaluation system included 17 evaluation points in 4 categories: “Basic management capacity” “Basic conditions of facilities and equipments” “The prevention and control capacity of nosocomial infection” and “The emergency response capacity”. Each evaluation point contained 3 quantitative evaluation indicators. The Cronbach’s α coefficients of the expert questionnaire consultation were 0.914 and 0.883, respectively. The scale-level content validity index was 0.932, and the item-level content validity index ranged from 0.823 to 1. Conclusions The evaluation system constructed in this study can be used for quantitative evaluation and quality self-examination of the prevention and control ability of respiratory infectious diseases in general hospitals. It also contributes to the continuous improvement of the quality of nosocomial infection prevention and control.
ObjectiveTo summarize the methods and research progress of imaging evaluation of liver iron concentration.MethodsThe current status and progress of different imaging techniques in liver iron overload research were reviewed by studying the relevant literatures at home and abroad. The methods for determining liver iron concentration and their advantages and disadvantages were summarized.ResultsThe imaging methods for determining liver iron concentration mainly included traditional non-enhanced CT and dual energy CT examination, magnetic resonance signal intensity ratio, relative signal intensity index, T2 and R2 values, magnetic resonance spectroscopy, T2* and R2* values, susceptibility weighted imaging, and quantitative susceptibility mapping.ConclusionLiver iron quantification imaging method, including dual-energy CT and magnetic resonance imaging could non-invasively and accurately assess the liver iron overload.
