A Channel-Dimensional Feature-Reconstructed Deep Learning Model for Predicting Breast Cancer Molecular Subtypes on Overall b-Value Diffusion-Weighted MRI

BACKGROUND

Dynamic contrast-enhanced (DCE) MRI commonly outperforms diffusion-weighted (DW) MRI in breast cancer discrimination. However, the side effects of contrast agents limit the use of DCE-MRI, particularly in patients with chronic kidney disease.

PURPOSE

To develop a novel deep learning model to fully exploit the potential of overall b-value DW-MRI without the need for a contrast agent in predicting breast cancer molecular subtypes and to evaluate its performance in comparison with DCE-MRI.

STUDY TYPE

Prospective.

SUBJECTS

486 female breast cancer patients (training/validation/test: 64%/16%/20%).

FIELD STRENGTH/SEQUENCE

3.0 T/DW-MRI (13 b-values) and DCE-MRI (one precontrast and five postcontrast phases).

ASSESSMENT

The breast cancers were divided into four subtypes: luminal A, luminal B, HER2+, and triple negative. A channel-dimensional feature-reconstructed (CDFR) deep neural network (DNN) was proposed to predict these subtypes using pathological diagnosis as the reference standard. Additionally, a non-CDFR DNN (NCDFR-DNN) was built for comparative purposes. A mixture ensemble DNN (ME-DNN) integrating two CDFR-DNNs was constructed to identify subtypes on multiparametric MRI (MP-MRI) combing DW-MRI and DCE-MRI.

STATISTICAL TESTS

Model performance was evaluated using accuracy, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC). Model comparisons were performed using the one-way analysis of variance with least significant difference post hoc test and the DeLong test. P < 0.05 was considered significant.

RESULTS

The CDFR-DNN (accuracies, 0.79 ~ 0.80; AUCs, 0.93 ~ 0.94) demonstrated significantly improved predictive performance than the NCDFR-DNN (accuracies, 0.76 ~ 0.78; AUCs, 0.92 ~ 0.93) on DW-MRI. Utilizing the CDFR-DNN, DW-MRI attained the predictive performance equal (P = 0.065 ~ 1.000) to DCE-MRI (accuracies, 0.79 ~ 0.80; AUCs, 0.93 ~ 0.95). The predictive performance of the ME-DNN on MP-MRI (accuracies, 0.85 ~ 0.87; AUCs, 0.96 ~ 0.97) was superior to those of both the CDFR-DNN and NCDFR-DNN on either DW-MRI or DCE-MRI.

DATA CONCLUSION

The CDFR-DNN enabled overall b-value DW-MRI to achieve the predictive performance comparable to DCE-MRI. MP-MRI outperformed DW-MRI and DCE-MRI in subtype prediction.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY STAGE: 1.

[Construction of a risk prediction model for diabetes after kidney transplantation based on genome-wide association study]

Objective: To explore the clinical risk factors and susceptibility genes of diabetes after kidney transplantation (PTDM) and construct a risk prediction model for PTDM. Methods: The data of kidney transplant recipients who underwent follow-up in the Affiliated Lihuili Hospital, Ningbo University and Sir Run Run Shaw Hospital, Zhejiang University School of Medicine from January 2001 to December 2022 were retrospectively analyzed. The recipients were divided into PTDM group and Non-PTDM group according to whether they were complicated with PTDM. The differences in clinical indicators between the two groups were compared, the risk factors affecting the incidence of PTDM were determined, and susceptibility genes of PTDM were screened by genome-wide association study (GWAS). PTDM risk prediction models based only on clinical indicators (Model 1) and clinical indicators combined with susceptibility genes (Model 2) were established respectively, and the predictive performance of the two prediction models was compared. Finally, the Nomogram of the optimal model was drawn, and the discrimination, calibration and clinical applicability of the model were evaluated. Results: A total of 113 kidney transplant recipients (70 males and 43 females) were included, with an average age of (46.2±10.8) years. There were 51 cases in PTDM group and 62 cases in Non-PTDM group. The related factors screened by GWAS and logistic regression analysis included family history of diabetes (OR=88.912, 95%CI: 5.827-1 356.601, P=0.001), preoperative triglyceride (TG) (OR=1.888, 95 %CI: 1.150-3.098, P=0.012), uric acid (UA) (OR=1.011, 95%CI: 1.000-1.022, P=0.045) and rs802707 (OR=10.046, 95%CI: 1.462-69.042, P=0.019). The area under the curve (AUC) of the receiver operating characteristics analysis (ROC) predicted by Model 1 for PTDM was 0.891 (95%CI: 0.811-0.972), with the sensitivity of 0.889 and the specificity of 0.742. The AUC of ROC curve predicted by Model 2 for PTDM was 0.930 (95%CI: 0.864-0.995), with the sensitivity of 0.885 and the specificity of 0.900. Conclusions: Family history of diabetes, preoperative TG and UA, and rs802707 are significantly associated with the occurrence of PTDM. In addition, the combination of susceptibility genes could improve the predictive ability of clinical indicators for the risk of PTDM.

Comparison of Dynamic Contrast-Enhanced MRI and Non-Mono-Exponential Model-Based Diffusion-Weighted Imaging for the Prediction of Prognostic Biomarkers and Molecular Subtypes of Breast Cancer Based on Radiomics

BACKGROUND

Dynamic contrast-enhanced (DCE) MRI and non-mono-exponential model-based diffusion-weighted imaging (NME-DWI) that does not require contrast agent can both characterize breast cancer. However, which technique is superior remains unclear.

PURPOSE

To compare the performances of DCE-MRI, NME-DWI and their combination as multiparametric MRI (MP-MRI) in the prediction of breast cancer prognostic biomarkers and molecular subtypes based on radiomics.

STUDY TYPE

Prospective.

POPULATION

A total of 477 female patients with 483 breast cancers (5-fold cross-validation: training/validation, 80%/20%).

FIELD STRENGTH/SEQUENCE

A 3.0 T/DCE-MRI (6 dynamic frames) and NME-DWI (13 b values).

ASSESSMENT

After data preprocessing, high-throughput features were extracted from each tumor volume of interest, and optimal features were selected using recursive feature elimination method. To identify ER+ vs. ER-, PR+ vs. PR-, HER2+ vs. HER2-, Ki-67+ vs. Ki-67-, luminal A/B vs. nonluminal A/B, and triple negative (TN) vs. non-TN, the following models were implemented: random forest, adaptive boosting, support vector machine, linear discriminant analysis, and logistic regression.

STATISTICAL TESTS

Student's t, chi-square, and Fisher's exact tests were applied on clinical characteristics to confirm whether significant differences exist between different statuses (±) of prognostic biomarkers or molecular subtypes. The model performances were compared between the DCE-MRI, NME-DWI, and MP-MRI datasets using the area under the receiver-operating characteristic curve (AUC) and the DeLong test. P < 0.05 was considered significant.

RESULTS

With few exceptions, no significant differences (P = 0.062-0.984) were observed in the AUCs of models for six classification tasks between the DCE-MRI (AUC = 0.62-0.87) and NME-DWI (AUC = 0.62-0.91) datasets, while the model performances on the two imaging datasets were significantly poorer than on the MP-MRI dataset (AUC = 0.68-0.93). Additionally, the random forest and adaptive boosting models (AUC = 0.62-0.93) outperformed other three models (AUC = 0.62-0.90).

DATA CONCLUSION

NME-DWI was comparable with DCE-MRI in predictive performance and could be used as an alternative technique. Besides, MP-MRI demonstrated significantly higher AUCs than either DCE-MRI or NME-DWI.

EVIDENCE LEVEL

2.

TECHNICAL EFFICACY

Stage 2.

Deep wavelet scattering orthogonal fusion network for glioma IDH mutation status prediction

Accurately predicting the isocitrate dehydrogenase (IDH) mutation status of gliomas is greatly significant for formulating appropriate treatment plans and evaluating the prognoses of gliomas. Although existing studies can accurately predict the IDH mutation status of gliomas based on multimodal magnetic resonance (MR) images and machine learning methods, most of these methods cannot fully explore multimodal information and effectively predict IDH status for datasets acquired from multiple centers. To address this issue, a novel wavelet scattering (WS)-based orthogonal fusion network (WSOFNet) was proposed in this work to predict the IDH mutation status of gliomas from multiple centers. First, transformation-invariant features were extracted from multimodal MR images with a WS network, and then the multimodal WS features were used instead of the original images as the inputs of WSOFNet and were fully fused through an adaptive multimodal feature fusion module (AMF2M) and an orthogonal projection module (OPM). Finally, the fused features were input into a fully connected classifier to predict IDH mutation status. In addition, to achieve improved prediction accuracy, four auxiliary losses were also used in the feature extraction modules. The comparison results showed that the prediction area under the curve (AUC) of WSOFNet on a single-center dataset was 0.9966 and that on a multicenter dataset was approximately 0.9655, which was at least 3.9% higher than that of state-of-the-art methods. Moreover, the ablation experimental results also proved that the adaptive multimodal feature fusion strategy based on orthogonal projection could effectively improve the prediction performance of the model, especially for an external validation dataset.

MD-SGT: Multi-dilation spherical graph transformer for unsupervised medical image registration

Deformable medical image registration is an essential preprocess step for several clinical applications. Even though the existing convolutional neural network and transformer based methods achieved the promising results, the limited long-range spatial dependence and non-uniform attention span of these models prohibit further improving the registration performance. To deal with this issue, we proposed a multi-dilation spherical graph transformer (MD-SGT), in which the encoder combined the advantages of convolutional and graph transformer blocks to distinguish effectively the differences between the reference and the template images at various scales. Specifically, the features of each voxel were obtained by aggregating the information from its neighbors sampled from different spherical regions with different dilation rates. The implicit convolution inductive bias and long-range uniform attention span induced by such information aggregation manner made the features more representative for registration. Through the qualitative and quantitative comparisons with state-of-the-art methods on two datasets, we demonstrated that combining long-range uniform attention span and inductive bias are beneficial for promoting the image registration performance, with the Dice score, ASD and HD95 being improved at least by 0.5%, 2.2% and 1.1%, respectively.

[Analysis of surgical strategy for pediatric papillary thyroid carcinoma with low-intermediate risk]

Objective: To explore the feasibility and rationality of lobectomy in the treatment of pediatric thyroid papillary carcinoma (PTC) with low-intermediate risk. Methods: The clinicopathological features and follow-up data of pediatric PTC with low-intermediate risk were reviewed from March 2000 to December 2018 in Cancer Hospital of Chinese Academy of Medical Sciences. The correlations between different surgical procedures and prognoses were evaluated. Propensity score matching(PSM) was used to adjust for risk factors, and the difference in prognoses between the total thyroidectomy (TT) group and the lobectomy (LT) group was compared. Results: A total of 140 patients were included in the study, including 36 males and 104 females. The age range was from 6-year-old to 18-year-old. There were 43 low-risk patients and 97 intermediate-risk patients. The median follow-up time was 87.5 months, ranging from 8 to 241 months, and 20 patients (14.3%) showed recurrence during the follow-up period. Univariate analysis showed that N1b, extrathyroidal extension, the number of lymph node metastasis>5, the ratio of lymph node metastasis≥0.19, and radioactive iodine treatment were risk factors for recurrence (all P value below 0.05), but multivariate analysis showed that only the ratio of lymph node metastasis≥0.19 (HR=8.69, 95%CI=1.08-70.21, P=0.043) was an independent risk factor for recurrence. There was no significant difference in the 5-year recurrence free survival rates between TT group and LT group before propensity score matching (82.8% vs. 86.5%, χ²=0.219, P=0.640) and after propensity score matching (89.6% vs. 90.4%, χ²=0.099, P=0.753). Conclusion: There is no significant difference in recurrence-free survival between TT group and LT group. Lobectomy is feasible for selective pediatric PTC with low-intermediate risk.

[Effectiveness, safety and cost of urinary follicle stimulating hormone in controlled ovarian stimulation in China: multi-center retrospective cohort study of 102 061 in vitro fertilization cycles]

Objective: To explore the effectiveness, safety and cost between urinary follicle stimulating hormone (uFSH) and recombinant follicle stimulating hormone (rFSH) in controlled ovarian stimulation (COS) in China. Methods: Data were collected from 16 reproductive centers in China covering oocytes collection time from May 1, 2015 to June 30, 2018. Eligible patients were over 18 years old, adopting COS with uFSH (uFSH group) or rFSH (rFSH group) as start gonadotropins (Gn), and using in vitro fertilization (IVF) and (or) intracytoplasmic sperm injection for fertilisation, excluding frozen embryo recovery cycle. Generalised estimating equation was used to address the violation of independency assumption between cycles due to multiple IVF cycles for one person and clustering nature of cycles carried out within one center. Controlling variables included age, body mass index, anti-Müllerian hormone level, cause of infertility, ovulation protocol, type of fertilisation, number of embryos transferred, number of days of Gn use. Results: Totally 102 061 cycles met eligibility criteria and were included in the analyses. In terms of effectiveness, after controlling relevant unbalanced baseline characteristics, compared with rFSH group, the high oocyte retrieval (>15 oocytes was considered high retrieval) rate of uFSH group significantly decreased in gonadotropin-releasing hormone agonist protocol (OR=0.642, P<0.01) and in gonadotropin-releasing hormone antagonist protocol (OR=0.556, P=0.001), but the clinical pregnancy rate per transfer cycle and the live birth rate per transfer cycle significantly increased (OR=1.179, OR=1.169, both P<0.01) in both agonist and antagonist protocols. For safety, multiple analysis result demonstrated that in the agonist protocol, compared with rFSH group, the incidence of moderate to severe ovarian hyperstimulation syndrome of uFSH group significantly decreased (OR=0.644, P=0.002). The differences in ectopic pregnancy rate and multiple pregnancy rate between the uFSH and rFSH groups were not significant (P=0.890, P=0.470) in all patients. In terms of cost, compared with rFSH group, the uFSH group had lower total Gn costs for each patient (P<0.01). Conclusion: For patients who underwent COS, uFSH has better safety, and economic profiles over rFSH in China.

[Research progress in the methodology used in phenome-wide association studies]

Phenome-wide association study (PheWAS) is a reverse genetic analysis method to identify the potential phenotypes associated with genetic variations. With the increasing availability of biomedical databases and electronic medical records (EMR), PheWAS has gradually become an effective tool to unveil the relationships between exposure and a broad range of health phenotypes. The unique advantage of this method is that it can simultaneously explore the associations of a specific exposure with a variety of disease outcomes, thus helping to reveal multiple causal relationships and the shared pathogenic mechanisms among diseases. However, PheWAS has limitations, including selecting instrumental variables and the heavy burden of various corrections. In addition, how to interpret the biological mechanisms underlying significant findings is another crucial issue of PheWAS. This review will focus on the methodology and application of PheWAS to provide meaningful suggestions and insights for future studies.

Radiomic analysis based on multi-phase magnetic resonance imaging to predict preoperatively microvascular invasion in hepatocellular carcinoma

BACKGROUND

The prognosis of hepatocellular carcinoma (HCC) remains poor and relapse occurs in more than half of patients within 2 years after hepatectomy. In terms of recent studies, microvascular invasion (MVI) is one of the potential predictors of recurrence. Accurate preoperative prediction of MVI is potentially beneficial to the optimization of treatment planning.

AIM

To develop a radiomic analysis model based on pre-operative magnetic resonance imaging (MRI) data to predict MVI in HCC.

METHODS

A total of 113 patients recruited to this study have been diagnosed as having HCC with histological confirmation, among whom 73 were found to have MVI and 40 were not. All the patients received preoperative examination by Gd-enhanced MRI and then curative hepatectomy. We manually delineated the tumor lesion on the largest cross-sectional area of the tumor and the adjacent two images on MRI, namely, the regions of interest. Quantitative analyses included most discriminant factors (MDFs) developed using linear discriminant analysis algorithm and histogram analysis with MaZda software. Independent significant variables of clinical and radiological features and MDFs for the prediction of MVI were estimated and a discriminant model was established by univariate and multivariate logistic regression analysis. Prediction ability of the above-mentioned parameters or model was then evaluated by receiver operating characteristic (ROC) curve analysis. Five-fold cross-validation was also applied via R software.

RESULTS

The area under the ROC curve (AUC) of the MDF (0.77-0.85) outperformed that of histogram parameters (0.51-0.74). After multivariate analysis, MDF values of the arterial and portal venous phase, and peritumoral hypointensity in the hepatobiliary phase were identified to be independent predictors of MVI (P < 0.05). The AUC value of the model was 0.939 [95% confidence interval (CI): 0.893-0.984, standard error: 0.023]. The result of internal five-fold cross-validation (AUC: 0.912, 95%CI: 0.841-0.959, standard error: 0.0298) also showed favorable predictive efficacy.

CONCLUSION

Noninvasive MRI radiomic model based on MDF values and imaging biomarkers may be useful to make preoperative prediction of MVI in patients with primary HCC.

[Comparison and thoughts of the training system for thoracic surgeons]

There is no unified thoracic surgery training system in China, neither in the trainee selection or evaluation, nor in the training curriculum or the graduation requirements. A literature review was performed for available publications regarding international thoracic surgical training. A brief comparison was made regarding the thoracic surgery residency programs in China, Japan, United States and United Kingdom, including training pathway, recruitments, training content, performance assessment and academic experience. In conclusion, there are four key aspects worth noting. Firstly, an effective residency programme is invaluable to specialty training, and effort should be made to create a unified training programme that allows trainee to progress from residency to specialty training smoothly. Secondly, flexibility and personalization should be allowed in higher specialty training, so that trainee can develop their subspecialty interests. Thirdly, a unified clinical curriculum, selection and standardized income should be promoted to minimalize the variation of training outcome between provinces. Fourthly, additional training and time should be allowed for trainee who wants to pursue an academic career, and academic outcomes should be evaluated alongside with the standard clinical training.

[Drug selection for simultaneous treatment of tuberculosis combined with hepatitis C virus infection]

Clinically, patients with tuberculosis (TB) combined with hepatitis C virus (HCV) infection often require simultaneous treatment. Consequently, when anti-HCV and TB drugs are used in combination drug-drug interactions (DDIs), anti-TB drug-induced hepatotoxicity, and liver disease states need to be considered. This paper focuses on discussing the metabolic mechanisms of commonly used anti-TB and HCV drugs and the selection options of combined drugs, so as to provide rational drug use for TB patients combined with HCV infection.

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Objective: To examine the safety and feasibility of uniportal video-assisted thoracoscopic (VATS) decortication in patients presenting with stage Ⅲ tuberculous empyema. Methods: From August 2017 to July 2020, 158 patients of stage Ⅲ tuberculous empyema underwent uniportal VATS decortication with partial rib resection and customized periosteal stripper in Department of Thoracic Surgery, Shanghai Pulmonary Hospital. There were 127 males and 31 females, aged (M(IQR)) 32(28) years (range:14 to 78 years). Follow-up was performed in the outpatient clinic or via social communication applications, at monthly thereafter. If there was no air leak and chest tube drainage was less than 50 ml/day, a chest CT was performed. If the lung was fully re-expanded, chest tubes were removed. All patients received a follow-up chest CT 3 to 6 months following their initial operations which was compared to their preoperative imaging. Results: There was one conversion to open thoracotomy. The operative time was 2.75 (2.50) hours (range: 1.5 to 7.0 hours), and median blood loss was 100 (500) ml (range: 50 to 2 000 ml). There were no perioperative mortalities. There were no major complications except 1 case of redo-VATS for hemostasis due to excessive drainage and 1 case of incision infection, The incidence of prolonged air leaks (>5 days) was 80.3%(126/157). The postoperative hospital stay was 5.00 (2.25) days (range:2 to 15 days). All patients were discharged with 2 chest tubes, and the median duration drainage was 21.00 (22.50) days (range: 3 to 77 days). Follow-up was completed in all patients over a duration of 20 (14) months (range: 12 to 44 months). At follow-up, 149 patients(94.9%) recovered to grade Ⅰ level, 7 patients to grade Ⅱ level, and 1 patient to grade Ⅲ level. Conclusion: Uniportal VATS decortication involving partial rib resection and a customized periosteal stripper is safe and effective for patients with stage Ⅲ tuberculous empyema.

Short-Term Repeatability of in Vivo Cardiac Intravoxel Incoherent Motion Tensor Imaging in Healthy Human Volunteers

BACKGROUND

Intravoxel incoherent motion (IVIM) tensor imaging is a promising technique for diagnosis and monitoring of cardiovascular diseases. Knowledge about measurement repeatability, however, remains limited.

PURPOSE

To evaluate short-term repeatability of IVIM tensor imaging in normal in vivo human hearts.

STUDY TYPE

Prospective.

POPULATION

Ten healthy subjects without history of heart diseases.

FIELD STRENGTH/SEQUENCE

Balanced steady-state free-precession cine sequence and single-shot spin-echo echo planar IVIM tensor imaging sequence (9 b-values, 0-400 seconds/mm² and six diffusion-encoding directions) at 3.0 T.

ASSESSMENT

Subjects were scanned twice with an interval of 15 minutes, leaving the scanner between studies. The signal-to-noise ratio (SNR) was evaluated in anterior, lateral, septal, and inferior segments of the left ventricle wall. Fractional anisotropy (FA), mean diffusivity (MD), mean fraction (MF), and helix angle (HA) in the four segments were independently measured by five radiologists.

STATISTICAL TESTS

IVIM tensor indexes were compared between observers using a one-way analysis of variance or between scans using a paired t-test (normal data) or a Wilcoxon rank-sum test (non-normal data). Interobserver agreement and test-retest repeatability were assessed using the intraclass correlation coefficient (ICC), within-subject coefficient of variation (WCV), and Bland-Altman limits of agreements.

RESULTS

SNR of inferior segment was significantly lower than the other three segments, and inferior segment was therefore excluded from repeatability analysis. Interobserver repeatability was excellent for all IVIM tensor indexes (ICC: 0.886-0.972; WCV: 0.62%-4.22%). Test-retest repeatability was excellent for MD of the self-diffusion tensor (D) and MF of the perfusion fraction tensor (f_p ) (ICC: 0.803-0.888; WCV: 1.42%-9.51%) and moderate for FA and MD of the pseudo-diffusion tensor (D^* ) (ICC: 0.487-0.532; WCV: 6.98%-10.89%). FA of D and f_p and HA of D presented good test-retest repeatability (ICC: 0.732-0.788; WCV: 3.28%-8.71%).

DATA CONCLUSION

The D and f_p indexes exhibited satisfactory repeatability, but further efforts were needed to improve repeatability of D^* indexes.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 1.

[Formation of study population for causal inference]

Epidemiological analysis describes and compares the characteristics of a certain number of people to make causal inferences. The formation of the study population is always the first step. In this paper, we first define the concepts of cross-sections at both individual level and population level and introduce the three assumptions needed in the measurements in observational studies, i. e. the true values of the attributes are stable with time, the attribute variables are independent and the individuals are independent during the measuring process. We also determine that the causal inference research should be unified based on the time of the occurrence or beginning of a postulated cause, or exposure, should be in. Then, based on the dual roles of the population cross-section with causal thinking, we propose that research designs can be classified into two types with different characteristics: history reconstruction research and future exploration research. Finally, we briefly analyze the research design framework and the relationship between estimated effects and different designs. The discussion of the formation of a study population from the perspective of causal thinking can make a foundation for the classification of causal inference research design with appropriate effect parameters, which needs to be further studied.

Learning Tubule-Sensitive CNNs for Pulmonary Airway and Artery-Vein Segmentation in CT

Training convolutional neural networks (CNNs) for segmentation of pulmonary airway, artery, and vein is challenging due to sparse supervisory signals caused by the severe class imbalance between tubular targets and background. We present a CNNs-based method for accurate airway and artery-vein segmentation in non-contrast computed tomography. It enjoys superior sensitivity to tenuous peripheral bronchioles, arterioles, and venules. The method first uses a feature recalibration module to make the best use of features learned from the neural networks. Spatial information of features is properly integrated to retain relative priority of activated regions, which benefits the subsequent channel-wise recalibration. Then, attention distillation module is introduced to reinforce representation learning of tubular objects. Fine-grained details in high-resolution attention maps are passing down from one layer to its previous layer recursively to enrich context. Anatomy prior of lung context map and distance transform map is designed and incorporated for better artery-vein differentiation capacity. Extensive experiments demonstrated considerable performance gains brought by these components. Compared with state-of-the-art methods, our method extracted much more branches while maintaining competitive overall segmentation performance. Codes and models are available at http://www.pami.sjtu.edu.cn/News/56.

Investigation of intravoxel incoherent motion tensor imaging for the characterization of the in vivo human heart

PURPOSE

To investigate intravoxel incoherent motion (IVIM) tensor imaging of the in vivo human heart and elucidate whether the estimation of IVIM tensors is affected by the complexity of pseudo-diffusion components in myocardium.

METHODS

The cardiac IVIM data of 10 healthy subjects were acquired using a diffusion weighted spin-echo echo-planar imaging sequence along 6 gradient directions with 10 b values (0~400 s/mm² ). The IVIM data of left ventricle myocardium were fitted to the IVIM tensor model. The complexity of myocardial pseudo-diffusion components was reduced through exclusion of low b values (0 and 5 s/mm² ) from the IVIM curve-fitting analysis. The fractional anisotropy, mean fraction/mean diffusivity, and Westin measurements of pseudo-diffusion tensors (f_p and D*) and self-diffusion tensor (D), as well as the angle between the main eigenvector of f_p (or D*) and that of D, were computed and compared before and after excluding low b values.

RESULTS

The fractional anisotropy values of f_p and D* without low b value participation were significantly higher (P < .001) than those with low b value participation, but an opposite trend was found for the mean fraction/diffusivity values. Besides, after removing low b values, the angle between the main eigenvector of f_p (or D*) and that of D became small, and both f_p and D* tensors presented significant decrease of spherical components and significant increase of linear components.

CONCLUSION

The presence of multiple pseudo-diffusion components in myocardium indeed influences the estimation of IVIM tensors. The IVIM tensor model needs to be further improved to account for the complexity of myocardial microcirculatory network and blood flow.

[A comparative study of four cross-sectional investigations on the status of pediatric intensive care unit in China over the past 30 years]

Objective: To understand the history, current situation and trends of intensive care unit (ICU) of pediatrics in China over the past 30 years. Methods: The results of the cross-sectional investigation on the status of ICU of pediatrics in 2014 were compared with those in 1993, 2001 and 2009. The main measurements were the number of participated provinces and hospitals, the availability of equipment, staffing, and medical technologies, the major diseases and the source of the patients. Besides, the equipment allocation and technology implementation in 2014 were compared with the standards in the "recommendations on grading construction and management of children's intensive care unit in China" published in 2016. Results: The contents of the four surveys were slightly different, with only a few measurements not documented in one or more surveys. (1) The number of provinces and hospitals involved in the four surveys were 20 hospitals in 14 provinces in year 1993, 27 hospitals in 17 provinces in year 2001, 33 hospitals in 25 provinces in year 2009 and 108 hospitals in 25 provinces in year 2014. (2) In 1993, 2001, 2009 and 2014, the ratio of doctors/beds were 0.7∶1,0.8∶1, (0.4-0.5) ∶1 and 0.5∶1, and the ratio of nurses/beds were 1.1∶1,1.4∶1, (1.1-1.7) ∶1 and 1.3∶1, respectively. (3) Regarding the equipment availability, in 1993, 2001, 2009, and 2014, the numbers of monitors were 0.3/ICU, 0.3/bed, 1.1-1.4/bed and 1.0/bed; the numbers of invasive ventilators were 0.4/bed, 0.5/bed, 0.6/bed and 0.4/bed, respectively. In 2001, 2009 and 2014, there were 60.0%, 100.0% (33/33) and 88.0% (95/108) of the participating ICU equipped with blood gas analyzer, and 70.0%, 93.9% (31/33) and 90.7% (98/108) with bedside X-ray machines, respectively. In 2009 and 2014, 69.7% (23/33) and 92.6% (100/108) ICU were equipped with non-invasive ventilators respectively. In 2014, 10.2% (11/108) ICU were equipped with extracorporeal membrane oxygenation (ECMO) equipment and 45.4% (49/108) ICU with bedside continuous blood purification equipment. In 1993, 2001 and 2014, the numbers of infusion pump were 0.5/ICU, 1.1/bed and 1.7/bed, respectively. (4) Regarding the conducted medical technology, in 2014, invasive mechanical ventilation was used in 100% (108/108) ICU, and non-invasive ventilation in 89.8% (97/108) ICU. High frequency ventilation was used in 78.8% (26/33) and 38.0% (41/108) ICU in 2009 and 2014 respectively. Blood purification was used in 22.0%, 69.7% (23/33) and 47.2% (51/108) ICU, and the application of surfactant was in 48.0%, 97.0% (32/33) and 24.1% (26/108) ICU in 2001, 2009 and 2014, respectively. Nitric oxide inhalation (iNO) was used in 24.0% and 9.3% (10/108) in 2001 and 2014 respectively. ECMO was used in 6 and 7 hospitals in 2009 and 2014 respectively. (5) Compared with the criteria in the "recommendations on grading construction and management of children's intensive care units in China" in 2016, only the availability of monitors and conventional mechanical ventilation in 2014 met the standards.The original data in 2001 was not shown due to the lack of absolute values. Conclusions: The number of ICU of pediatrics and its beds in China increased significantly from 1993 to 2014, as well as the equipment availability and the conducted medical technology. But the status in 2014 was still far behind the recommendations in 2016, with a significant shortage of professional staff.

[Clinical and laboratory analysis of 17 patients with γδT-cell large granular lymphocyte leukemia]

目的

比较γδT细胞大颗粒淋巴细胞白血病（γδT-LGLL）与αβT细胞大颗粒淋巴细胞白血病（αβT-LGLL）的临床及实验室特征。

方法

回顾性分析中国医学科学院血液病医院贫血诊疗中心2009年1月至2019年1月17例γδT-LGLL患者的临床及实验室结果，与同时期91例αβT-LGLL患者进行对比。

结果

17例γδT-LGLL患者中位年龄54（25~73）岁，10例就诊原因为贫血。γδT-LGLL与αβT-LGLL一致，脾大（41%和44%）较为常见，肝大（12%和5%）及淋巴结肿大（6%和8%）较为少见；两者均有较高的抗核抗体阳性率（59%和45%），较低的风湿因子阳性率（6%和10%）；两者中性粒细胞绝对值、淋巴细胞绝对值、HGB及PLT差异均无统计学意义（P值均>0.05）。γδT-LGLL患者的典型免疫分型为CD3⁺/CD4⁻/CD8⁻/CD57⁺/TCRγδ⁺，CD4⁻/CD8⁻双阴性表型显著多于αβT-LGLL患者（P<0.001）。17例γδT-LGLL患者有1例口服泼尼松治疗，3例口服环孢素A治疗，13例口服环孢素A联合泼尼松治疗，治疗4个月后2例获得完全缓解，4例获得部分缓解，总体有效率为35%。

结论

γδT-LGLL是一种少见的成熟T淋巴细胞增殖性疾病，其临床及实验室表现与αβT-LGLL相比除CD4⁻/CD8⁻双阴性表型外均无显著差异。环孢素A可作为γδT-LGLL的首选治疗药物。

[Correlation between multi-slice spiral CT determined epicardial adipose tissue volume and atrial fibrillation]

Objective: To determine the relationship between volume of epicardial adipose tissue (EAT) and atrial fibrillation (AF) . Methods: A total of 207 patients who hospitalized in the Department of Cardiology, Nantong University Affiliated Hospital from January 2016 to June 2018 were included in this study. They were divided into two groups, including AF group (n=125) and sinus rhythm group (n=82). The AF group included 80 paroxysmal AF (PAF) and 45 persistent AF (PeAF) patients. Total EAT and left atrial EAT (LA-EAT) volume were measured using 256 rows of multi-slice spiral CT in all patients. Echocardiographic derived left ventricular ejection fraction (LVEF) and left atrial diameter (LAD) were analyzed. Hospholipase A2 and blood lipids were examined in all patients. The baseline data and EAT volume of all groups were compared. The multivariate logistic regression was used to analyze the risk factors related to the occurrence of AF. The correlation between total EAT volume and LA-EAT volume and LAD were analyzed by Pearson correlation. Result: The volume of total EAT in patients with sinus rhythm, AF, PAF and PeAF were (92.2±32.1), (136.0±46.0), (134.2±46.3) and (140.1±52.6)cm(3), respectively. The volume of LA-EAT in patients with sinus rhythm, AF, PeAF and PAF were (27.1±7.5), (39.2±19.2), (35.9± 17.0) and (45.1±21.5)cm(3), respectively. Total EAT and LA-EAT volume were significantly larger in PAF and PeAF groups than in sinus rhythm group (all P<0.01). The LA-EAT volume was larger in PeAF group than in PAF group (P<0.01), but total EAT volume was similar between two groups (P>0.05). Logistic regression analysis showed that total EAT volume (OR=1.202, 95%CI 1.083-1.334, P=0.001), LA-EAT volume (OR=1.051, 95%CI 1.003-1.101, P=0.037) and LAD (OR=1.019, 95%CI 1.005-1.032, P=0.006) were the independent related factors of AF. Pearson correlation analysis showed that the total EAT volume was positively correlated with LAD (r=0.466, P<0.01) and LA-EAT volume was positively correlated with LAD (r=0.290, P<0.01). Conclusion: The volume of total EAT and LA-EAT measured by 256-row multi-slice spiral CT is significantly correlated with the incidence of AF.

Reconstruction of an idiopathic hemipalatal hypoplasia: report of a case

Idiopathic hemipalatal hypoplasia is rare and leads to speech problems and the regurgitation of fluids, and the reconstruction of asymmetrical velopharyngeal incompetence is a challenge to the cleft surgeon. We present a case in a 5-year-old boy, and introduce the one-stage surgical technique that we used to resolve it.

[Red blood cell lifespan detected by endogenous carbon monoxide breath test in patients with polycythemia vera]

Objective: To detect the red blood cell lifespan in patients with polycythemia vera (PV), and explore the influencing factors. Methods: From February 2017 to December 2018, 27 patients with PV at Blood Diseases Hospital, Chinese Academy of Medical Science and 18 normal controls were recruited. Red blood cell lifespan was detected by endogenous carbon monoxide (CO) breath test. The related factors were analyzed. Results: The average red blood cell lifespan of 27 PV patients was 80 (range, 35-120) days (d), which was significantly shorter than that of the normal controls [110.5(69-166) d, P<0.05], namely 35.3 d shorter. The red blood cell lifespan of ten newly diagnosed patients and 17 patients who were treated with hydroxyurea and/or interferon were 98 (35-117) d and 69 (45-120) d, respectively, which were both shorter than that of the normal control (P=0.010, 0.000). Correlation analysis showed that red blood cell lifespan of patients with newly diagnosed PV was associated with JAK2 mutation allele burden (r=0.900, P=0.037), peripheral blood lymphocyte count (r=-0.742, P=0.014) and the level of serum vitamin B(12) (r=-0.821, P=0.023). Conclusion: The lifespan of red blood cells in patients with PV is about one-third shorter than normal, and is related to JAK2 mutation allele burden, absolute lymphocyte count, and serum vitamin B(12) level.

Varifocal-Net: A Chromosome Classification Approach Using Deep Convolutional Networks

Chromosome classification is critical for karyotyping in abnormality diagnosis. To expedite the diagnosis, we present a novel method named Varifocal-Net for simultaneous classification of chromosome's type and polarity using deep convolutional networks. The approach consists of one global-scale network (G-Net) and one local-scale network (L-Net). It follows three stages. The first stage is to learn both global and local features. We extract global features and detect finer local regions via the G-Net. By proposing a varifocal mechanism, we zoom into local parts and extract local features via the L-Net. Residual learning and multi-task learning strategies are utilized to promote high-level feature extraction. The detection of discriminative local parts is fulfilled by a localization subnet of the G-Net, whose training process involves both supervised and weakly supervised learning. The second stage is to build two multi-layer perceptron classifiers that exploit features of both two scales to boost classification performance. The third stage is to introduce a dispatch strategy of assigning each chromosome to a type within each patient case, by utilizing the domain knowledge of karyotyping. The evaluation results from 1909 karyotyping cases showed that the proposed Varifocal-Net achieved the highest accuracy per patient case (%) of 99.2 for both type and polarity tasks. It outperformed state-of-the-art methods, demonstrating the effectiveness of our varifocal mechanism, multi-scale feature ensemble, and dispatch strategy. The proposed method has been applied to assist practical karyotype diagnosis.

[The effect of three trigger methodson pregnancy outcome of intrauterine insemination]

Objective: To analysepregnancy outcome of intrauterine insemination(IUI) after three different trigger methods. Methods: A retrospective study was designed, included 341 couples seeking for their first or second IUI cycle from 2016.7 to 2018.6 in women's hospital, school of medicine, zhejiang university. Ovulation was trigger by HCG 10 000 IU in 154 cases named HCG group, by 0.1/0.2 mg triptorelinin 94 cases called GnRHa group, by HCG combined with triptorelinin in 93 cases defined as dual trigger group. The primary outcome was clinical pregnancy rate and ongoing pregnancy rate beyond 28 gestational weeks,second outcome which contains biochemical pregnancy, miscarriagerate, ectopic pregnancy rateand multiple pregnancy rate were also observed in three groups. Results: Pregnancy outcomeshowed no significant difference among three groups. Conclusions: The study suggested that all this three methods(HCG trigger, GnRHa trigger, HCG combined with GnRHa dual trigger) couldinduced ovulation, their effects on IUI pregnancyout come were similar.

[Retrospective analysis of 4 rare cases of temporomandibular joint disc ossification]

Objective: To summarize the clinical manifestation and treatment of temporomandibular joint (TMJ) disc ossification, providing reference for clinical diagnosis and treatment of TMJ disc ossification. Methods: From January 2006 to January 2018, 4 patients with TMJ disc ossification (2 males and 2 females, aged 20-55 years with an average age of 35.5 years) which were admitted to the Department of Oral and Maxillofacial Surgery, Shenzhen Second People's Hospital were analyzed retrospectively. Ossification of TMJ disc was found in 4 cases during TMJ surgery. Two cases underwent partial ossification resection plus disc reduction and anchorage, and two cases underwent discectomy plus temporalis myofascial flap replacement. The causes, clinical manifestations and surgical effects of TMJ disc ossification were analyzed by comparing the maximal interincisal opening, visual analogue scale (VAS) score and MRI imaging indexes before and after operation. Results: The history of anterior disc displacement of TMJ in 4 patients was long (average 11.5 years). In clinic, TMJ disc ossification was characterized by TMJ pain and limitation of mouth opening. The maximal interincisal opening was (32.1±6.1) mm and the VAS score was (7.3±0.4) before operation. MRI showed that the displaced discs of the affected sides were displaced and the condyle bones were worn. During the operation, ossification of TMJ discs was found yellow and hard, and the original elasticity was lost. Pathologic findings showed that the TMJ disc cartilage were ossified to osteoid tissue. Under the microscope, bone cells scattered around the bone cells and red trabecular bone were seen, and there were bone trabecula formed. In a follow-up of one year, TMJ pain was significantly decreased [VAS: (1.7±0.2)], and the maximal interincisal opening was (38.5±2.2) mm. MRI showed that the TMJ disc returned to normal position, and the sign of repairing and reconstruction of condyle bone could be found. Conclusions: Long term displacement of TMJ disc may cause ossification with pain and limitation of interincisal opening. According to the degree and extent of ossification, partial ossification plus disc reduction and anchorage or discectomy plus temporalis myofascial flap replacement is feasible, and the clinical effects are satisfactory.

Non-mono-exponential diffusion models for assessing early response of liver metastases to chemotherapy in colorectal Cancer

Background

Preoperative chemotherapy is becoming standard therapy for liver metastasis from colorectal cancer, so early assessment of treatment response is crucial to make a reasonable therapeutic regimen and avoid overtreatment, especially for patients with severe side effects. The role of three non-mono-exponential diffusion models, such as the kurtosis model, the stretched exponential model and the statistical model, were explored in this study to early assess the response to chemotherapy in patients with liver metastasis from colorectal cancer.

Methods

Thirty-three patients diagnosed as colorectal liver metastasis were evaluated in this study. Diffusion-weighted images with b values (0, 200, 500, 1000, 1500, 2000 s/mm²) were acquired at 3.0 T. The parameters (ADC_k, K, DDC,α, D_sand σ) were derived from three non-mono-exponential models (the kurtosis, stretched exponential and statistical models) as well as their corresponding percentage changes before and after chemotherapy. The difference in above parameters between the response and non-response groups were analyzed with independent-samples T-test (normality) and Mann–Whitney U-test (non-normality). Meanwhile, receiver operating characteristic curve (ROC) analyses were performed to assess the response to chemotherapy.

Results

Significantly lower values of K (the kurtosis coefficient derived from the kurtosis model) and σ (the width of diffusion coefficient distribution in the statistical model) (P < 0.05) were observed in the respond group before treatment, as well as higher ΔK and Δσ values (P < 0.05) after the first cycle of chemotherapy were also found compared with the non-respond group. ROC analyses showed the K value acquired before treatment had the highest diagnostic performance (0.746) in distinguishing responders from non-responders. Furthermore, the high sensitivity (100%) and accuracy (76.3%) from the K value before treatment was found in assessing the response of colorectal liver metastasis to chemotherapy.

Conclusions

The non-mono-exponential diffusion models may be able to predict early response to chemotherapy in patients with colorectal liver metastasis.

Structure Prior Constrained Estimation of Human Cardiac Diffusion Tensors

OBJECTIVE

The purpose of this paper is to increase the accuracy of human cardiac diffusion tensor (DT) estimation in diffusion magnetic resonance imaging (dMRI) with a few diffusion gradient directions.

METHODS

A structure prior constrained (SPC) method is proposed. The method consists in introducing two regularizers in the conventional nonlinear least squares estimator. The two regularizers penalize the dissimilarity between neighboring DTs and the difference between estimated and prior fiber orientations, respectively. A novel numerical solution is presented to ensure the positive definite estimation.

RESULTS

Experiments on ex vivo human cardiac data show that the SPC method is able to well estimate DTs at most voxels, and is superior to state-of-the-art methods in terms of the mean errors of principal eigenvector, second eigenvector, helix angle, transverse angle, fractional anisotropy, and mean diffusivity.

CONCLUSION

The SPC method is a practical and reliable alternative to current denoising- or regularization-based methods for the estimation of human cardiac DT.

SIGNIFICANCE

The SPC method is able to accurately estimate human cardiac DTs in dMRI with a few diffusion gradient directions.

The expression changes and correlation analysis of high mobility group box-1 and tissue factor in the serum of rats with sepsis

OBJECTIVE

To investigate the expression changes of high mobility group box-1 (HMGB-1) and tissue factor (TF) and their correlation in the serum of sepsis rat models.

MATERIALS AND METHODS

30 rats were divided into the sham-operated group, 15 rats were in the control group. The cecal ligation and puncture method was used to make the animal model with abdominal infection induced by sepsis. There were 15 rats in the sepsis group among which they were divided into 3 subgroups at different time points after modeling (after 6 hours, 12 hours, 24 hours). Cardiac function indicators of the rats in each subgroup were monitored, including heart rate (HR), left ventricular end-diastolic pressure (LVEDP) and left ventricular developed pressure (LVDP), and enzyme-linked immunosorbent assay (ELISA) was used to test the changes of the expression levels of HMGB-1 and TF in the serum of the rats after 6 hours, 12 hours, 24 hours. Pearson correlation analysis was used to analyze the correlation between HMGB-1 and TF.

RESULTS

HR and LVEDP of the rats in the sepsis group were significantly higher than those of the rats in the control group. The differences were statistically significant (p<0.050). LVDP of the rats in the sepsis group was markedly lower than that of the rats in the control group. The differences were statistically significant (p<0.050). The expressions of HMGB-1 and TF of the rats in the subgroups of the sepsis group were higher than those of the rats in the control group after 6 hours, 12 hours, 24 hours; the expression levels of HMGB-1 and TF of the rats with sepsis increased with time. The differences were statistically significant (p<0.050). When the expressions of HMGB-1 and TF of the rats in the sepsis group were compared with each other within the group the differences were significantly different (p<0.050). The expressions of HMGB-1 and TF in the subgroups at the 24th hour were significantly higher than those at the 6th hour. The differences were statistically significant (p<0.050). The differences of the expression of TF of the rats in the control group were not statistically significant (p>0.050). There was a significant positive correlation between HMGB-1 and TF of the rats in the sepsis group (r=0.772, p=0.002).

CONCLUSIONS

The expression levels of HMGB-1 and TF of the rats with sepsis gradually increased with time, and the level of HMGB-1 was positively correlated with the level of TF.

Pulmonary nodule segmentation with CT sample synthesis using adversarial networks

PURPOSE

Segmentation of pulmonary nodules is critical for the analysis of nodules and lung cancer diagnosis. We present a novel framework of segmentation for various types of nodules using convolutional neural networks (CNNs).

METHODS

The proposed framework is composed of two major parts. The first part is to increase the variety of samples and build a more balanced dataset. A conditional generative adversarial network (cGAN) is employed to produce synthetic CT images. Semantic labels are generated to impart spatial contextual knowledge to the network. Nine attribute scoring labels are combined as well to preserve nodule features. To refine the realism of synthesized samples, reconstruction error loss is introduced into cGAN. The second part is to train a nodule segmentation network on the extended dataset. We build a three-dimensional (3D) CNN model that exploits heterogeneous maps including edge maps and local binary pattern maps. The incorporation of these maps informs the model of texture patterns and boundary information of nodules, which assists high-level feature learning for segmentation. Residual unit, which learns to reduce residual error, is adopted to accelerate training and improve accuracy.

RESULTS

Validation on LIDC-IDRI dataset demonstrates that the generated samples are realistic. The mean squared error and average cosine similarity between real and synthesized samples are 1.55 × 10 - 2 and 0.9534, respectively. The Dice coefficient, positive predicted value, sensitivity, and accuracy are, respectively, 0.8483, 0.8895, 0.8511, and 0.9904 for the segmentation results.

CONCLUSIONS

The proposed 3D CNN segmentation framework, based on the use of synthesized samples and multiple maps with residual learning, achieves more accurate nodule segmentation compared to existing state-of-the-art methods. The proposed CT image synthesis method can not only output samples close to real images but also allow for stochastic variation in image diversity.

Evaluation of non-monoexponential diffusion models for hepatocellular carcinoma using b values up to 2000 s/mm2 : A short-term repeatability study

BACKGROUND

Non-monoexponential diffusion models are being used increasingly for the characterization and curative effect evaluation of hepatocellular carcinoma (HCC). But the fitting quality of the models and the repeatability of their parameters have not been assessed for HCC.

PURPOSE

To evaluate kurtosis, stretched exponential, and statistical models for diffusion-weighted imaging (DWI) of HCC, using b-values up to 2000 s/mm² , in terms of fitting quality and repeatability.

STUDY TYPE

Prospective.

POPULATION

Eighteen patients with HCC.

FIELD STRENGTH/SEQUENCE

Conventional and DW images (b = 0, 200, 500, 1000, 1500, 2000 s/mm² ) were acquired at 3.0T.

ASSESSMENT

The parameters of the kurtosis, stretched exponential, and statistical models were calculated on regions of interest (ROIs) of each lesion.

STATISTICAL TESTS

The fitting quality was evaluated through comparing the fitting residuals produced on the average data of ROI between different models using a paired t-test or Wilcoxon rank-sum test. Repeatability of the fitted parameters at the median values on the voxelwise data of ROI was assessed using the within coefficient of variation (WCV), the intraclass correlation coefficient (ICC), and the 95% Bland-Altman limits of agreements (BA-LA). The repeatability was divided into four levels: excellent, good, acceptable, and poor, referring to the values of ICC and WCV.

RESULTS

Among three models, the stretched exponential model provided the best fit to HCC (P < 0.05), whereas the statistical model produced the largest fitting residuals (P < 0.05). The repeatability of K from the kurtosis model was excellent (ICC 0.915; WCV 8.79%), while the distributed diffusion coefficient (DDC) from the stretched model was just acceptable (ICC 0.477; WCV 27.83%). The repeatability was good for other diffusion-related parameters.

DATA CONCLUSION

Considering the model fit and repeatability, the kurtosis and stretched exponential models are the preferred models for the description of the DW signals of HCC with respect to the statistical model.

LEVEL OF EVIDENCE

2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:297-304.

Determination of Hepatocellular Carcinoma and Characterization of Hepatic Focal Lesions with Adaptive Multi-Exponential Intravoxel Incoherent Motion Model

PURPOSE: To distinguish hepatocellular carcinoma (HCC) from other types of hepatic lesions with the adaptive multi-exponential IVIM model. METHODS: 94 hepatic focal lesions, including 38 HCC, 16 metastasis, 12 focal nodular hyperplasia, 13 cholangiocarcinoma, and 15 hemangioma, were examined in this study. Diffusion-weighted images were acquired with 13 b values (b = 0, 3, …, 500 s/mm²) to measure the adaptive multi-exponential IVIM parameters, namely, pure diffusion coefficient (D), diffusion fraction (f_d), pseudo-diffusion coefficient (D_i*) and perfusion-related diffusion fraction (f_i) of the ith perfusion component. Comparison of the parameters of and their diagnostic performance was determined using Mann-Whitney U test, independent-sample t test, one-way analysis of variance, Z test and receiver-operating characteristic analysis. RESULTS: D, D₁* and D₂* presented significantly difference between HCCs and other hepatic lesions, whereas f_d, f₁ and f₂ did not show statistical differences. In the differential diagnosis of HCCs from other hepatic lesions, D₂* (AUC, 0.927) provided best diagnostic performance among all parameters. Additionally, the number of exponential terms in the model was also an important indicator for distinguishing HCCs from other hepatic lesions. In the benign and malignant analysis, D gave the greatest AUC values, 0.895 or 0.853, for differentiation between malignant and benign lesions with three or two exponential terms. Most parameters were not significantly different between hypovascular and hypervascular lesions. For multiple comparisons, significant differences of D, D₁* or D₂* were found between certain lesion types. CONCLUSION: The adaptive multi-exponential IVIM model was useful and reliable to distinguish HCC from other hepatic lesions.

[Primary research of early oral feeding after total laryngectomy]

Objective: To explore whether early oral feeding after total laryngectomy is safe and effective by evaluating the incidence of pharyngocutaneous fistula (PCF) and the hospital duration. Methods: A retrospective cohort study was conducted, including 52 patients underwent total laryngectomy, plus partial tongue base resection (n=2), partial pharyngectomy (n=1), or pedicle flap (n=2) between January 2012 and October 2017. Patients who had a history of preoperative radiotherapy, chemotherapy or chemoradiotherapy, previous surgery for larynx or pharynx and who had severe complications were excluded. Early oral feeding started between 48 h and 72 h postoperatively, while delayed oral feeding started within postoperative day 8-10. The incidences of PCF in two groups were compared to evaluate whether PCF and early oral feeding was related. Multi-variables analysis was conducted to evaluate risk factors for PCF. Results: PCF rate was 19.2% among all patients, 11.1% in patients with early oral feeding and 23.5% in patients with delayed oral feeding. No significant statistically difference in PCF rate was found between two groups (χ(2)=0.506, P=0.477). Multi-variables analysis showed that oral feeding time (early or delayed) was not a independent risk factor of PCF (Two classification response variable Logistic regression, P=0.200, OR=0.242, 95%CI[0.028-2.118]). But low preoperative albumin level was observed as an independent risk factor for PCF (P=0.039, OR=0.848, 95% CI [0.726-0.992]). A negative correlation was observed between preoperative albumin level and PCF. And also there was not a significant difference in hospital duration between patients with early oral feeding and delayed oral feeding(U=268, P=0.464). Conclusion: For patients total laryngectomy with no previous history of radiotherapy, chemotherapy, chemoradiotherapy, early oral feeding after surgery is safe and effective.

[Survey on the prevalence of continuous blood purification in Chinese pediatric critical care]

Objective: To investigate the current application status of continuous blood purification (CBP) technology and equipment in pediatric intensive care unit (PICU) in China. Methods: A cross-sectional survey was conducted to understand the current popularization of CBP technology and equipment, the management of CBP equipment and consumables, and the application of CBP in different diseases. A questionnaire named Application Status of Continuous Blood Purification Technology was applied. Children's hospitals and polyclinic hospitals with the pediatric qualification (pediatric emergency or critical care unit members of Chinese Medical Association and Chinese Medical Doctor Association) were selected. Results: From December 2016 to February 2017, 53 hospitals completed the questionnaire, including 7 in northeast, 6 in north China, 16 in east China, 9 in south China, 5 in central China, 4 in the northwest, and 6 in the southwest region. Continuous renal replacement therapy (CRRT), the most widely used technology, was carried out in 51 hospitals. Other technologies were peritoneal dialysis (IPD) (n=37), artificial liver support (ALSS) (n=26) and blood adsorption (PA) (n=13). There were 107 CBP machines in the 51 hospitals used CBP technology, with an average of 2.10/hospital. In 36 hospitals CBP machines were managed independently by PICU (70%). Hospitals made their own displacement liquid (n=40, 78%), or purchased displacement liquid (n=11, 22%). Hospitals prepared dialysate on their own (n=38, 75%), or purchased dialysate (n=13 hospitals, 25%). In 46 (90%) hospitals, hemodialysis catheter was placed independently by PICU doctors. The routine operation and maintenance of CBP were mainly completed by the PICU nurses in 36 hospitals (71%). There were 39 hospitals (76%) where professional nurses manage and maintain CBP. Puncture sites were femoral vein (n=26, 51%), internal jugular vein (n=21, 41%) and venae subclavia (n=4, 8%). Forty-two hospitals (82%) selected B-mode ultrasound positioning and guidance when performing internal jugular vein puncture. A total of 40 (78%) hospitals have developed post dilution and combined dilution techniques during the implementation of CBP. The most common indications of CBP technology were different in different regions. They were sepsis in northeast (24.0%, 243/1 011) and east China region (32.0%, 982/3 069), multiple organ dysfunction syndrome in south China (29.2%, 444/1 520), north China (15.8%, 126/796), and southwest region (30.1%, 460/1 526), drug poisoning in central China region (21.6%, 325/1 506), and renal failure in northwest region (53.0%, 44/83). Conclusions: CBP technology is widely used in the field of pediatric severe diseases in China. The eastern regions possess more CBP equipment than the western regions. CBP is widely used in the treatment of sepsis.

[Clinical study on locking plate for the treatment of non-osteoporotic complex proximal humeral fractures]

OBJECTIVE

To describe long-term results of locking plate used for the treatment of non-osteoporotic fresh three- and four-part proximal humeral fractures with at least 2 years follow-up.

METHODS

The functional outcomes and the complications of non-osteoporotic three- and four-part fresh proximal humeral fractures treated with locking plate were assessed retrospectively. The active range of motion, the Constant score, the University of California at Los Angeles (UCLA) shoulder score, the visual analogue score (VAS) were employed to evaluate the postoperative shoulder function, and the radiographic images were taken to evaluate the neck-shaft angle of the proximal humeral and postoperative implant-related complications.

RESULTS

From January 2007 to October 2014, 107 consecutive fresh three- and four-part non-osteoporotic fresh proximal humeral fractures were treated with a locking plate in our department. Among them, 67 patients completed at least 2 years follow-up. The average follow-up time was (43.9±23.3) months (range: 24-108 months). The mean Constant score was 87.1±11.7 (range: 51-100), the mean UCLA score was 30.5±3.9 (range: 18-35), the mean VAS score was 1±2 (range: 0-7). The mean active forward flexion was 159.0°±19.3° (range: 80°-180°), the mean external rotation was 36.8°±19.5°(0°-80°) and the mean internal rotation was T11 level (T2-LS level). There were 11 patients who suffered from complications. Screw perforations were observed in 5 (7.5%) patients, avascular necrosis of the humeral head was observed in 9 (13.4%) patients and traumatic osteoarthritis was observed in 5 (7.5%) patients. Six patients showed two or more complications. There was no significant difference in outcomes when comparing the patients with three- part fractures (31 patients) with those with four-part fractures (36 patients). The rates of complications and avascular necrosis were significantly higher in the four-part fracture group than in the three-part fracture group.

CONCLUSION

The locking plate is an effective method in treating three- and four-part non-osteoporotic fresh proximal humeral fractures. Strict surgical indication and precise surgical skill are the key points for successful treating non-osteoporotic fresh proximal humeral fractures. There is a higher rate of complications and avascular necrosis of the humeral head in the four-part fractures than in the three-part fractures.

[Clinical analysis of secondary cervical lymph node dissection in papillary thyroid carcinoma]

Objective: To investigate the value of secondary cervical lymph node dissection in papillary thyroid carcinoma (PTC). Methods: PTC patients with recurrence re-operated in a previously dissected area at our hospital during 2000-2016 were included in this analysis. Patients were divided according to the operative interval of 6 months. The level and number of lymph node metastasis and the number of lymph node dissection were analyzed to calculate the ratio of lymph node metastasis. Results: A total of 336 PTC patients received 360 side lateral cervical lymph nodes dissection. The ratio of recurrence in unilateral lateral neck is 92.9%(312/336). The ratio of recurrence in multiple levels (more than two regions) were 47.5% (171/360). The recurrence ratio of level Ⅱ, Ⅲ, Ⅳ and Ⅴ were 55.6%(200/360), 44.2%(159/360), 59.7%(215/360) and 10.3%(37/360), respectively. Lymph node metastases were inclined to level Ⅱ (33.6%) and Ⅳ (35.8%). The mean number of lymph node dissection and metastasis in the group of operative interval ≤ 6 months was 26.56 per case and 4.37 per case, respectively. The mean number of lymph node dissection and metastasis in the group of operative interval >6 months was 16.80 per case and 3.20 per case, respectively. The number of lymph node dissection and metastasis between these two groups were significantly different (P=0.001, P<0.001). Conclusions: Lymph node metastasis of PTC patients with secondary cervical lymph node dissection are inclined to level Ⅱ and level Ⅳ. Moreover, multi-level metastasis is not rare. Level Ⅱ and level Ⅳ require more attention in the first operation. Most of the patients undergo reoperation because of residual lymph nodes from the previous treatment. Normalization and completeness of the initial dissection are particularly important to PTC patients.

[Expression of enterotoxigenic Bacteroides fragilis and polyketide synthase gene-expressing Escherichia coli in colorectal adenoma patients]

OBJECTIVE

To investigate the distribution of various bacteria in adenoma tissue of colorectal adenoma (T/CRA), normal colonic mucosa tissue adjacent to the adenoma (N/CRA), and healthy colonic mucosa tissue (N/H) by comparing the number of total bacteria, Bacteroides fragilis (BF), enterotoxigenic Bacteroides fragilis (ETBF), polyketide synthase (pks) gene-expressing Escherichia coli(E.coli)(pks(+) E. coli)among the above 3 types of tissues.

METHODS

A total of 36 patients diagnosed with colorectal adenoma by colonoscopy and pathology in Department of Gastroenterology, Peking University People's Hospital from September 2011 to September 2013 were selected into this study. T/CRA and N/CRA tissues from the 36 patients and N/H tissues from 18 healthy controls were collected for DNA extraction. The number of total bacteria, BF, ETBF, pks(+) E. coli was detected by quantitative real time PCR, and their correlation with colorectal adenoma was analyzed.

RESULTS

(1) The number of total bacteria decreased gradually from N/H, N/CRA, to T/CRA, with the median values being 3.18×10(8,) 1.57×10(8,) and 7.91×10(7) copies/g, respectively, and with significant difference among the three groups and between each two groups (all P<0.01). (2) The content of BF decreased gradually from N/H, N/CRA, to T/CRA, the median values being 6.03×10(5,) 4.28×10(4,) and 5.48×10(3) copies/g, respectively, and with significant difference among the three groups and between each two groups (all P<0.01). (3) The toxin content produced by ETBF increased from N/H, N/CRA, to T/CRA, the relative expression being 1.73±0.30, 6.15±1.52, and 8.54±1.80, respectively. Significant difference was found between the T/CRA and N/H tissue (P=0.003), but not between any other two groups. (4) The expression of clbB in pks(+) E.coli was highest in T/CRA colonic tissue (2.96±0.28), followed by the N/CRA (2.79±0.19) and N/H tissue (1.06±0.08). Significant difference was found between T/CRA and N/H tissues, as well as between N/CRA and N/H tissues (both P<0.001), but not between T/CRA and N/CRA tissues.

CONCLUSIONS

The number of total bacteria is markedly reduced in the colonic mucosa of CRA patients compared to normal people, while the expressions of ETBF and pks(+) E.coli are significantly increased. Such changes in total bacterial, ETBF and pks(+) E.coli concentrations in colonic mucosa may be related to the tumorigenesis of colorectal adenoma.

Image-Based Investigation of Human in Vivo Myofibre Strain

Cardiac myofibre deformation is an important determinant of the mechanical function of the heart. Quantification of myofibre strain relies on 3D measurements of ventricular wall motion interpreted with respect to the tissue microstructure. In this study, we estimated in vivo myofibre strain using 3D structural and functional atlases of the human heart. A finite element modelling framework was developed to incorporate myofibre orientations of the left ventricle (LV) extracted from 7 explanted normal human hearts imaged ex vivo with diffusion tensor magnetic resonance imaging (DTMRI) and kinematic measurements from 7 normal volunteers imaged in vivo with tagged MRI. Myofibre strain was extracted from the DTMRI and 3D strain from the tagged MRI. We investigated: i) the spatio-temporal variation of myofibre strain throughout the cardiac cycle; ii) the sensitivity of myofibre strain estimates to the variation in myofibre angle between individuals; and iii) the sensitivity of myofibre strain estimates to variations in wall motion between individuals. Our analysis results indicate that end systolic (ES) myofibre strain is approximately homogeneous throughout the entire LV, irrespective of the inter-individual variation in myofibre orientation. Additionally, inter-subject variability in myofibre orientations has greater effect on the variabilities in myofibre strain estimates than the ventricular wall motions. This study provided the first quantitative evidence of homogeneity of ES myofibre strain using minimally-invasive medical images of the human heart and demonstrated that image-based modelling framework can provide detailed insight to the mechanical behaviour of the myofibres, which may be used as a biomarker for cardiac diseases that affect cardiac mechanics.

Association of CYP1A1 MspI polymorphism with oral cancer risk in Asian populations: a meta-analysis

Numerous studies regarding the association between the CYP1A1 MspI polymorphism and oral cancer risk in Asian populations have shown controversial results. To get a more precise estimation of this relationship, we conducted a comprehensive meta-analysis. PubMed, the Cochrane Library, Elsevier Science Direct, Web of Knowledge, the Chinese National Knowledge Infrastructure, VIP, and Wan Fang Med Online were searched. Pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) were calculated using fixed-effects or random-effects models. Heterogeneity among studies was assessed using the Cochran Q test and I(2) statistics. Twelve articles including 1925 oral cancer patients and 2335 controls were ultimately included in the meta-analysis. Overall, the meta-analysis showed that the CYP1A1 MspI polymorphism was associated with oral cancer risk in Asians (m1/m1 vs m2/m2: OR = 0.46, 95%CI = 0.30-070, POR = 0.000; m1/m1 vs m1/m2+m2/m2: OR = 0.70, 95%CI = 0.51-0.98, POR = 0.037; m1/m1+m1/m2 vs m2/m2: OR = 0.48, 95%CI = 0.35-0.65, POR = 0.000). Subgroup analyses showed that the control source (hospital-based or population-based), the genotyping method [polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism], the country in which the study was conducted, and Hardy-Weinberg equilibrium (Yes or No) were positively related to the association. Sensitivity analysis suggested that the overall results showed no significant change in three genetic models when any one study was removed, and publication bias was undetected by the Egger test. The CYP1A1 MspI polymorphism may be associated with oral cancer risk in Asian populations.

[Multi-disciplinary treatment increases the survival rate of late stage pharyngeal, laryngeal or cervical esophageal cancers treated by free jejunal flap reconstruction after cancer resection]

OBJECTIVE

To investigate the survival status of patients with pharyngeal, laryngeal or cervical esophageal cancers, who received free jejunal flap (FJF) to repair the defects following tumor resection, and to analyze the effect of multi-disciplinary treatment on their survival.

METHODS

Fifty-eight patients with pharyngeal, laryngeal or cervical esophageal cancer underwent free jejunal flap (FJF) reconstruction after cancer resection between 2010 and 2013. All their clinical records were reviewed and analyzed.

RESULTS

The success rate of flap transplantation was 91.4% (53/58). The 2-year overall survival rates (OSR) of cervical esophageal cancer and hypopharyngeal cancer patients were 67.5% and 49.3%, respectively, both were significantly better than that of laryngeal cancer. The main causes of death were local recurrence and distant metastases. The group with no short-term complications had a better two-year OSR (59.0%) than the group with short-term complications (46.6%), however, the difference between them was not significant (P=0.103). The 2-year survival rate of the initial treatment group was 65.0%, better than that of the salvage treatment group (49.4%), but the difference was not significant (P=0.051). For the stage III and IV patients, the multi-disciplinary treatment group had a significantly better 2-year OSR (64.7%) than the single or sequential treatment group (37.0%, P=0.016).

CONCLUSIONS

Free jejunal flap reconstruction is an ideal option for repairing the cervical digestive tract circumferential defects caused by tumor resection with a high success rate and a low mortality. Compared with the single or sequential treatment, multi-disciplinary treatment can significantly improve the survival rate of late-stage hypopharyngeal and cervical esophageal cancer patients.

[Efficacy analysis of two-stage reverse total shoulder arthroplasty for treating postoperative deep infection after surgeries for proximal humeral fractures]

OBJECTIVE

To evaluate the clinical results of two-stage reverse total shoulder arthroplasty for treating postoperative deep infection after surgeries for proximal humeral fractures.

METHODS

From January 2013 to December 2014, 8 consecutive patients with postoperative deep infection after surgeries for proximal humeral fractures who were treated with two-stage reverse total shoulder arthroplasty were retrospectively reviewed after the final follow-up. There were 1 man and 7 women with a mean age of (58.5±6.4) years, of whom 3 left shoulders and 5 right shoulders were involved. There were 2 patients with periprosthetic infection after hemiarthroplasty for proximal humeral fractures, and 6 patients with humeral head necrosis as well as implant-associated infection after open reduction internal fixation for proximal humeral fractures with the locking plate. The diagnosis of postoperative deep infection was confirmed by either the preoperative cultures or the intraoperative biopsies during the first-stage surgery. At the first-stage surgery, all the patients underwent a thorough debridement, and then an antibiotic-impregnated bone cement spacer was placed after the removal of prosthesis or locking plate. During the second-stage surgery, the cement spacer was removed, and then a revision shoulder arthroplasty with the reverse shoulder prosthesis was performed in all the patients who were routinely followed up after the second-stage surgery. The visual analogue score (VAS), Constant score and University of California Los Angeles (UCLA) score were employed to evaluate the postoperative shoulder function.

RESULTS

The mean follow-up time was (19.9±8.0) months (range 12 to 35 months). At the end of the follow-up, the median forward elevation [100° (60°, 140°) vs. 25° (0°, 90°), P=0.011], the median external rotation [15° (0°, 50°) vs. 5° (0°, 20°), P=0.048], and the median internal rotation [L4 (buttock, T12) vs. buttock (buttock, L3), P=0.041] were all significantly improved postoperatively. The median Constant score [53.5 (32, 74) vs. 29.0 (10, 57), P=0.012], the median UCLA score [20.5 (9, 26) vs. 9.5 (5, 15), P=0.012], and the median VAS score [1.5 (0, 5) vs. 5.0 (0, 8), P=0.018] were all significantly improved after the surgery. No recurrence of infection, prosthetic loosening or neurovascular injury was noted by the last follow-up.

CONCLUSION

two-stage reverse total shoulder arthroplasty was an effective treatment for the postoperative deep infection after surgeries for proximal humeral fractures. The shoulder function was postoperatively improved to a certain degree.

2-(3',5'-Dimethoxybenzylidene) cyclopentanone, a novel synthetic small-molecule compound, provides neuroprotective effects against ischemic stroke

2-(3',5'-Dimethoxybenzylidene) cyclopentanone (DMBC) is a novel small-molecule compound synthesized by our group. Here, we found that in rat models of permanent middle cerebral artery occlusion (pMCAO), intraperitoneal injection (ip) of DMBC at 1h after ischemia reduced infarct volume, improved neurological deficits and increased the protein levels of microtubule-associated protein 2 (MAP 2) and glial fibrillary acid protein (GFAP) in the ischemic cortex. Post-treatment of DMBC still produced neuroprotective effects even when administered at 6h after ischemia. In the oxygen-glucose deprivation (OGD)-induced astrocytes or HT22 cell injury, DMBC treatment decreased the OGD-induced lactate dehydrogenase (LDH) leakage and increased the GFAP levels in astrocytes. In addition, Annexin-V-Fluos staining analysis revealed that DMBC treatment attenuated both OGD-induced apoptosis and necrosis in astrocytes. Western blotting analysis showed DMBC treatment inhibited the ischemia or OGD-induced increases in active cathepsin B in the ischemic cortex or in astrocytes or HT22 cells. Immunofluorescence analysis demonstrated that DMBC treatment blocked the ischemia or OGD-induced release of cathepsin B from the lysosomes into the cytoplasm in the ischemic cortex or in astrocytes or HT22 cells. Taken together, our results indicate that DMBC can offer neuroprotective effects against cerebral ischemia with an extended therapeutic window and its mechanism might be associated with inhibition of the cathepsin B activation.

Guided Self-Assembly of Nano-Precipitates into Mesocrystals

We show by a combination of computer simulation and experimental characterization guided self-assembly of coherent nano-precipitates into a mesocrystal having a honeycomb structure in bulk materials. The structure consists of different orientation variants of a product phase precipitated out of the parent phase by heterogeneous nucleation on a hexagonal dislocation network. The predicted honeycomb mesocrystal has been confirmed by experimental observations in an Mg-Y-Nd alloy. The structure and lattice parameters of the mesocrystal and the size of the nano-precipitates are readily tuneable, offering ample opportunities to tailor its properties for a wide range of technological applications.

Multifiber pathway reconstruction using bundle constrained streamline

Fiber tractography techniques in diffusion magnetic resonance imaging have become a primary tool for studying the fiber architecture of biological tissues both noninvasively and in vivo. Streamline tracking, as a simple and efficient tractography technique, is widely used to reconstruct fiber pathways. It is however very sensitive to noisy estimation of local fiber orientations. In this paper, we propose a bundle constrained streamline method to accurately reconstruct multifiber pathways. The method introduces neighboring fiber consistency constraint in the tracking process and reconstructs fiber pathways that have optimal tradeoff between consistency with local fiber orientation estimations and similarity with neighboring fiber segment orientations. Results on synthetic, physical phantom and real human brain DW images show that the proposed method allows regular fiber pathways to be reconstructed and outperforms existing techniques.

[Modified arthroscopic Latarjet procedure for the treatment of anterior shoulder instability]

OBJECTIVE

To present the surgical technique and to evaluate the results of the modified arthroscopic Latarjet procedure.

METHODS

Arthroscopic Latarjet procedure has proven to be a reliable method of treatment for difficult anteroinferior instability of the shoulder joint. However, there is no anterior capsule reattachment and too much subscapularis damage for the classic procedure. From February 2013, we modified the classic procedure with reattachment of anterior joint capsule and muscle-tendon junction splitting of subscapularis. Coracoid graft position was evaluated using CT scanning.

RESULTS

From March 2012 to August 2014, 51 modified Latarjet procedures were successfully performed arthroscopically for patients with anterior shoulder instability. According to the CT scanning at the final follow up, the graft was flush with the glenoid in 94.1%, and medially placed in 5.9%. Vertical positioning was perfect in 96.0% (2 to 5 o'clock), too high in 2.0%, and too low in 2.0%. There were no cases of recurrent dislocation or subluxation.

CONCLUSION

The modified arthroscopic Latarjet procedure has shown satisfactory results with good graft positioning. It is a minimal invasive and accurate approach, which combines the advantages of the open procedure.

[Arthroscopic coracoclavicular ligament reconstruction versus open modified Weaver-Dunn procedure for acromioclavicular joint dislocations:comparison of curative effect]

OBJECTIVE

To compare the surgical outcomes between arthroscopic coracoclavicular ligament reconstruction and open modified Weaver-Dunn procedure for the treatment of acromioclavicular joint dislocations.

METHODS

From January 2011 to June 2012, 63 consecutive patients with acromioclavicular joint dislocations who were treated with either arthroscopic coracoclavicular ligament reconstruction or open modified Weaver-Dunn procedure were retrospectively reviewed after the final follow-up. There were 49 men and 14 women with a mean age of (40.3±10.6) years. The mean time from injury to surgery was (10.3±5.3) d. According to the Rockwood classification, there were 45 patients with type V injury and 18 patients with type III injury. All the patients with type III injury claimed high level of sport activity. The patients were divided into the arthroscopic surgery group (32 cases) or the open surgery group (31 cases) depending on the type of the surgery that each patient had taken. All the patients were routinely followed up after the surgery. The visual analogue score (VAS), American shoulder and elbow surgeons(ASES) score and University of California Los Angeles(UCLA) score were employed to evaluate the postoperative shoulder function. The postoperative radiographs of both shoulders were taken for each patient to evaluate the loss of reduction of the acromioclavicular joint.

RESULTS

The mean follow-up time was (29.6±6.0) months (range: 24 to 43 months). No significant difference was found between the arthroscopic surgery group and the open surgery group with regard to the patient's age [(41.0±10.5) years vs. (38.0± 10.8) years], gender (male/female,24/8 vs.25/6), classification (V/III,22/10 vs.23/8), time from injury to surgery [(10.6±4.9) d vs.(10.1±5.7) d], dominant involvement (19/32 vs.17/31)and mean follow-up time [(29.8±6.4) months vs.(29.5±5.5) months], P>0.05. At the end of the last follow-up, no significant difference was noted between the two groups regarding the mean forward elevation [(164.4±17.2) degrees vs.(162.6±12.9) degrees], mean external rotation [(60.9±17.0) degrees vs.(57.3±15.8) degrees], mean internal rotation [(T12±3 vertebrae) vs.(T12±3 vertebrae)], mean ASES scores (96.0±5.1 vs. 94.5±3.8)and UCLA scores (34.2±1.5 vs. 33.7±1.4), P>0.05.The rate of loss of reduction was significantly lower in the arthroscopic surgery group (1/32) compared with the open surgery group (7/31, P=0.026).

CONCLUSION

Surgical treatment for acromioclavicular joint dislocations with either arthroscopic reconstruction or open modified Weaver-Dunn procedure could yield good results with no significant difference between the two groups as for the postoperative shoulder function. The rate of loss of reduction was lower in the arthroscopic surgery group compared with that of the open surgery group.