Differentiating pancreatic adenosquamous carcinoma from pancreatic ductal adenocarcinoma by CT radiomic and deep learning features / 中华胰腺病杂志

Objective:To develop and validate the models based on mixed enhanced computed tomography (CT) radiomics and deep learning features, and evaluate the efficacy for differentiating pancreatic adenosquamous carcinoma (PASC) from pancreatic ductal adenocarcinoma (PDAC) before surgery.Methods:The clinical data of 201 patients with surgically resected and histopathologically confirmed PASC (PASC group) and 332 patients with surgically resected histopathologically confirmed PDAC (PDAC group) who underwent enhanced CT within 1 month before surgery in the First Affiliated Hospital of Naval Medical University from January 2011 to December 2020 were retrospectively collected. The patients were chronologically divided into a training set (treated between January 2011 and January 2018, 156 patients with PASC and 241 patients with PDAC) and a validation set (treated between February 2018 and December 2020, 45 patients with PASC and 91 patients with PDAC) according to the international consensus on the predictive model. The nnU-Net model was used for pancreatic tumor automatic segmentation, the clinical and CT images were evaluated, and radiomics features and deep learning features during portal vein phase were extracted; then the features were dimensionally reduced and screened. Binary logistic analysis was performed to develop the clinical, radiomics and deep learning models in the training set. The models' performances were determined by area under the ROC curve (AUC), sensitivity, specificity, accuracy, and decision curve analysis (DCA).Results:Significant differences were observed in tumor size, ring-enhancement, upstream pancreatic parenchymal atrophy and cystic degeneration of tumor both in PASC and PDAC group in the training and validation set (all P value <0.05). The multivariable logistic regression analysis showed the tumor size, ring-enhancement, dilation of the common bile duct and upstream pancreatic parenchymal atrophy were associated with PASC significantly in the clinical model. The ring-enhancement, dilation of the common bile duct, upstream pancreatic parenchymal atrophy and radiomics score were associated with PASC significantly in the radiomics model. The ring-enhancement, upstream pancreatic parenchymal atrophy and deep learning score were associated with PASC significantly in the deep learning model. The diagnostic efficacy of the deep learning model was highest, and the AUC, sensitivity, specificity, and accuracy of the deep learning model was 0.86 (95% CI 0.82-0.90), 75.00%, 84.23%, and 80.60% and those of clinical and radiomics models were 0.81 (95% CI 0.76-0.85), 62.18%, 85.89%, 76.57% and 0.84 (95% CI 0.80-0.88), 73.08%, 82.16%, 78.59% in the training set. In the validation set, the area AUC, sensitivity, specificity, and accuracy of deep learning model were 0.78 (95% CI 0.67-0.84), 68.89%, 78.02% and 75.00%, those of clinical and radiomics were 0.72 (95% CI 0.63-0.81), 77.78%, 59.34%, 65.44% and 0.75 (95% CI 0.66-0.84), 86.67%, 56.04%, 66.18%. The DCA in the training and validation sets showed that if the threshold probabilities were >0.05 and >0.1, respectively, using the deep learning model to distinguish PASC from PDAC was more beneficial for the patients than the treat-all-patients as having PDAC scheme or the treat-all-patients as having PASC scheme. Conclusions:The deep learning model based on CT automatic image segmentation of pancreatic neoplasm could effectively differentiate PASC from PDAC, and provide a new non-invasive method for confirming PASC before surgery.

Coronary Heart Disease and Obstructive Sleep Apnea Syndrome： Interpretation and Reflection Based on Simultaneous Treatment of Heart and Lung in Traditional Chinese Medicine / 中国实验方剂学杂志

As the overweight and obese population is growing， the incidence of obstructive sleep apnea is rising， and most of the cases are complicated with coronary heart disease and other cardiovascular diseases. The two diseases affect each other and seriously endanger the patients' health， becoming a major public health problem of global concern. It is of great clinical importance to explore the combination of Chinese and Western medicine in the prevention and treatment of coronary heart disease complicated with obstructive sleep apnea syndrome. Researchers have explored the relationship between the two based on traditional Chinese medicine（TCM） theory and found that the two diseases belong to the TCM disease categories of chest impediment and snoring， respectively， and their co-morbidity is associated with the abnormal physiological functions of the heart and lungs. The failure of the heart to govern blood leads to the generation of blood stasis， and that of the lung to govern Qi movement leads to the generation of phlegm. The accumulation of phlegm and blood stasis in the chest causes chest impediment and snoring due to obstruction of the airway. This paper discusses the internal linkage between the pathogenesis of coronary heart disease and obstructive sleep apnea syndrome in Chinese and Western medicine from the TCM theory of heart-lung correlation. Furthermore， this paper proposes the treatment principles of simultaneously treating the heart and lung and activating blood and resolving phlegm， aiming to provide a theoretical basis for the clinical prevention and treatment of coronary heart disease complicated with obstructive sleep apnea.

Traditional Chinese Medicine Prevention and Treatment Strategy of Cognitive Impairment Secondary to Cardiovascular Disease and Simultaneous Treatment of Heart and Brain / 中国实验方剂学杂志

Cognitive impairment secondary to cardiovascular disease is a common complication in the elderly population， which seriously threatens the health of patients and affects the long-term quality of life. Cardiovascular diseases can lead to vascular endothelial injury， cerebral hypoperfusion， and brain lesions， and then cause cognitive impairment. Cardiovascular risk factors also increase the risk of secondary cognitive impairment in patients. It is particularly important to seek for early diagnosis and traditional Chinese medicine （TCM） and western medicine prevention and treatment. Based on the "holistic concept"， TCM puts forward the theory of "the connection of heart and brain". The heart and brain are connected and both are in charge of mental activities. Heart injury affects the brain， resulting in abnormal consciousness， which is considered to be the pathogenesis of cognitive impairment secondary to cardiovascular disease in TCM. Later generations of doctors propose the theory of "simultaneous treatment of the heart and the brain" on the basis of "treating different diseases with the same treatment" and "the connection of heart and brain". The theory contains two meanings. One is that different diseases can be treated by the same method because of the same etiology and pathogenesis. The other is the coexistence of different diseases and the treatment should be targeted to the same risk factors. This paper systematically discussed the TCM pathogenesis of cognitive impairment secondary to cardiovascular disease and the prevention and treatment strategy of "simultaneous treatment of the heart and the brain". In this paper， the deficiency of qi and blood was the foundation， and the interaction of blood stasis and poison and the obstruction of the pulse and the loss of the body were the key factors. Activating blood， detoxifying arteries， and connecting the orifices were the main treatment method for the disease. This paper is expected to enrich the connotation of "simultaneous treatment of the heart and the brain"， and provide new ideas for the prevention and treatment of cognitive impairment secondary to the cardiovascular disease with TCM.

Development of a computed tomography nomogram for differentiating focal-type autoimmune pancreatitis from pancreatic ductal adenocarcinoma / 中华胰腺病杂志

Objective:To develop and validate a visualized computed tomography nomogram for differentiating focal-type autoimmune pancreatitis (fAIP) from pancreatic ductal adenocarcinoma (PDAC).Methods:This retrospective review included 42 consecutive patients with fAIP diagnosed according to the International Consensus Diagnostic Criteria and 242 consecutive patients with PDAC confirmed by pathology between January 2011 and December 2018 in the First Affiliated Hospital of Naval Medical University. Among them, 209 consecutive patients (25 fAIP and 184 PDAC) were enrolled in the development cohort; Seventy-five consecutive patients (17 fAIP and 58 PDAC) were enrolled in the validation cohort. CT image characteristics, including lesion location, size, enhancement mode and degree of mass enhancement in portal vein phase, pancreatic parenchymal atrophy, main pancreatic duct dilation, common bile duct dilation, cyst, acute obstructive pancreatitis, and vascular invasion were compared. Univariate and multivariate analysis were used to screen the independent predictive factors for fAIP and PDAC, based on which the nomogram was constructed and visualized. The receiver operating characteristic curve (ROC) was drawn and area under the curve (AUC) was calculated to evaluate the differential efficacy of the nomogram. The clinical usefulness of the nomogram was evaluated by decision curve analysis.Results:There were statistically significant differences on common bile duct dilation and the mode and degree of enhancement in portal phase between fAIP group and PDAC group in training set and validation set ( P<0.05). Univariate regression analysis showed that common bile duct dilation and degree of mass enhancement in portal vein were closely correlated with fAIP and PDAC phase between the two groups in training set and validation set; mass enhancement mode in portal vein phase and main pancreatic duct dilation were closely correlated with fAIP and PDAC in training set. Multivariate logistic regression analysis showed that common biliary duct dilatation ( OR=0.26, 95% CI 0.06-1.10, P=0.07), main pancreatic duct dilation ( OR=9.46, 95% CI 1.60-56.04, P<0.01) and mass mild hyper-enhancing in portal vein phase ( OR=0.003, 95% CI 0.0003-0.0278, P<0.0001) were the three independent predictors for fAIP and PDAC. Thus, the equation for predicting the probability of PDAC was 4.51-1.33× no dilatation of the common bile duct+ 2.25× the main pancreatic duct dilated-5.84× mass mild hyper-enhancing during the portal phase. The individualized prediction nomogram using these predictors of the fAIP achieved an AUC of 0.97 (95% CI 0.95-0.99) in the development set and 0.97(95% CI0.94-1.00) in the validation set. The sensitivity, specificity and accuracy of the model were 87.5%, 100% and 89% in the training set; and 94.83%, 94.12% and 94.67% in the validation set, respectively. The decision curve analysis demonstrated that the nomogram was clinically useful when the nomogram differentiated fAIP and PDAC at a rate of >0.2. Conclusions:The nomogram based on common bile duct dilation, main pancreatic duct dilation and mass enhancement in portal vein phase can be used as a useful tool for predicting fAIP and PDAC and provide valuable evidence for clinical decision.

A nomogram based on CT characteristics for differentiating mass-forming chronic pancreatitis from pancreatic ductal adenocarcinoma patients with chronic pancreatitis history / 中华胰腺病杂志

Objective:To develop a visualized nomogram with a predictive value to differentiate mass-forming chronic pancreatitis (MFCP) from pancreatic ductal adenocarcinoma (PDAC) patients with chronic pancreatitis (CP) history.Methods:The clinical and radiological data of 5 433 CP patients acoording to the Asia-Pacific Diagnostic Criteria between February 2011 and February 2021 in the First Affiliated Hospital of Naval Medical University were retrospectively analyzed, and 71 PDAC patients with CP history and 67 MFCP who underwent surgery or biopsy and pathologically confirmed were eventually enrolled. The training set included 44 patients with MFCP and 59 patients with PDAC who were diagnosed between February 2011 and April 2018. The validation set consisted of 23 patients with MFCP and 12 patients with PDAC who were diagnosed between May 2018 and February 2021. Univariate and multivariate logistic regression analyses were performed to develop a prediction model for PDAC and MFCP, and the model was visualized as a nomogram. ROC was used to evaluate the predictive efficacy of the nomogram, and the clinical usefulness was judged by decision curve analysis.Results:The univariate analysis showed that a significant association with pancreatic cancer were observed for the duct-to-parenchyma ratio ≥0.34, pancreatic duct cut-off, pancreatic portal hypertension, arterial CT attenuation, portal venous CT attenuation, delayed CT attenuation, and vascular invasion in both the training and validation cohorts, but the duct-penetrating sign in the training cohort only. The multivariable logistic regression analysis showed that statistically significant differences (all P value <0.05) existed in cystic degeneration, a duct-to-parenchyma ratio ≥0.34, the duct-penetrating sign, pancreatic portal hypertension and arterial CT attenuation between the two cohorts. The above parameters were selected for the logistic regression model. The predicted model=3.65-2.59×cystic degeneration+ 1.26×duct-to-parenchyma ratio≥0.34-1.40×duct-penetrating sign+ 1.36×pancreatic portal hypertension-0.05×arterial CT attenuation. Area under the curve, sensitivity, specificity and accuracy of the model-based nomogram were 0.87 (95 CI 0.80-0.94), 89.0%, 75.0% and 83.5% in the training cohort, and 0.94 (95 CI 0.82-0.99), 91.7%, 100% and 97.1% in the validation cohort, respectively. Decision curve analysis showed that when the nomogram differentiated MFCP from PDAC patients with CP history at a rate of 0.05-0.85, the application of the nomogram could benefit the patients. Conclusions:The nomogram based on CT radiological features accurately differentiated MFCP from PDAC patients with CP history and provide reference for guiding the treatment and judging the prognosis.

Establishment of a MRI prediction model for solid pseudopapilloma of pancreas and nonfunctional neuroendocrine tumor / 中华胰腺病杂志

Objective:To analyze the MRI findings of solid pseudopapilloma of the pancreas (SPTs) and nonfunctional pancreatic neuroendocrine tumors (PNETs), and to establish and verify the prediction model of SPTs and PNETs.Methods:The clinical and MRI data of 142 patients with SPTs and 137 patients with PNETs who underwent surgical resection and were confirmed by pathology in the First Affiliated Hospital of Naval Medical University from January 2013 to December 2020 were collected continuously. Age, gender, body mass index (BMI), lesion size, location, shape, boundary, cystic change, T 1WI signal, T 2WI signal, enhancement peak phase, whether the enhancement degree was higher than that of pancreatic parenchyma in the enhancement peak phase, enhancement pattern, whether pancreatic duct and common bile duct were dilated, whether the pancreas shrank, and whether it invaded adjacent organs and vessels were recorded. According to the international consensus on prediction model modeling, patients were divided into training set (106 SPTs and 100 PNETs between January 2013 and December 2018), and validation set (36 SPTs and 37 PNETs between January 2019 and December 2020). The above characteristics of patients in training and validation set were analyzed by univariate and multivariate logistic regression, and a prediction model was established to distinguish SPTs and PNETs, and then visualized as a nomogram. The receiver operating characteristic curve (ROC) of the nomogram of training set and verification set was drawn, and the area under the curve (AUC), sensitivity, specificity and accuracy were calculated to evaluate the prediction efficiency of the model, and the clinical application value of the prediction model was evaluated by decision curve analysis (DCA). Results:Univariate regression analysis showed that there were significant differences on age, gender, lesion size, shape, cystic change, T 1WI signal, peak phase of enhancement, degree of enhancement in peak phase, pattern of enhancement and invasion of adjacent organs between SPTs group and PNETs group (all P value <0.05). Multivariate regression analysis showed that the older age, male patients, the smaller lesion, no high signal on T 1WI, the enhancement peak phase located in arterial phase or venous phase, and the enhancement degree in peak phase higher than that of pancreatic parenchyma were the six independent predictors of PNETs. The prediction model was established by using these six factors and visualized as a nomogram. The formula for predicting PNETs probability was 4.31+ 1.13×age+ 1.31×tumor size-1.29×female-4.18×high T 1WI signal+ 1.28×the enhancement degree higher than that of pancreatic parenchyma -4.69 ×enhancement peak in delay phase. The prediction model was visualized as a nomogram. The AUC values in the training set and validation set were 0.99(95% CI0.977-1.000) and 0.97 (95% CI 0.926-1.000), respectively. The sensitivity, specificity and accuracy in the training set are 98.00%, 94.34% and 96.12% and in the validation set were 86.49%, 97.22% and 91.78% respectively. The results of decision curve analysis show that the prediction model can accurately diagnose SPTs and PNETs. Conclusions:The prediction model established in this study can accurately differentiate SPTs from PNETs, and can provide important information for clinical decision and prognosis.

Correlation between MDCT-based arterial radiomics score and the resection margin of superior mesenteric vein in patients with pancreatic head cancer / 中华胰腺病杂志

Objective:To accurately identify the relationship between the arterial radiomics score (rad-score) and pathologic superior mesenteric vein (SMV) resection margin in patients with pancreatic head cancer.Methods:The clinical data of 181 patients with pathologically confirmed pancreatic head cancer, who underwent multi-slice computed tomography (MDCT) within one month of resection in the First Affiliated Hospital of Naval Medical University between January 2016 and December 2018 were collected. Based on the pathology of SMV resection margin, the patients were divided into SMV negative margin group ( n=127) and SMV positive margin group ( n=54). The clinical, pathological and radiological features were compared between two groups. 3D slicer software was used to draw the region of interest in each layer of the primary CT arterial images for tumor segmentation. Rython package was applied to extract the radiomics features of pancreatic tumors after segmentation and the extracted features were reduced and chosen using the least absolute shrinkage and selection operator (Lasso) logistic regression algorithm. Lasso logistic regression formula was applied to calculated the arterial rad-score. Univariate and multivariate logistic regression models were used to analyze the association between the arterial rad-score and SMV resection margin. ROC was drawn and AUC, sensitivity, specificity and accuracy for diagnosing the SMV resection margin were calculated. The clinical usefulness of arterial rad-score for diagnosing SMV resection margin was determined by decision curve analysis (DCA). Results:There were statistical differences on LVSI and the touching angle of tumor and SMV/portal vein (PV) between SMV negative margin group and SMV positive margin group (all P<0.001). A total of 1 029 arterial radiomics CT features were obtained, and 14-selected arterial phase features associated with SMV resection margin were determined after being reduced by the Lasso logistic regression algorithm. Univariate analysis showed that the arterial radiomics score, LVSI, the touching angle of tumor and SMV/PV were all correlated with SMV resection margin (all P<0.001). Multivariate analyses confirmed that patients with high arterial radiomics score had a 3.63-fold risk of positive resection margin compared with that with low arterial radiomics score, and a higher arterial rad-score was associated with a higher risk of SMV positive resection margin ( P<0.0001). At the cut-off value of -0.711, AUC of the arterial rad-score for diagnosing SMV resection margin was 0.838, and the sensitivity, specificity and accuracy was 77.8%, 75.6% and 76.24%. Decision curve analysis demonstrated that the percentage of the arterial radiomics score for predicting the positive SMV resection margin was >0.02, and the application of the arterial radiomics score could benefit the patients. Conclusions:The arterial rad-score was strongly correlated with SMV resection margin of pancreatic cancer, and can accurately predict SMV resection margin and provide a new tool for preoperative noninvasive evaluation of the SMV resection margin.

The CT and pathologic features of pulmonary chondroma / 实用放射学杂志

Objective To explore the CT and pathologic manifestations of the pulmonary chondroma,to improve the diagnostic accuracy and reduce the misdiagnosis.Methods The CT data of 6 patients with pulmonary chondroma proved by pathology were analyzed retrospectively.Results All 6 cases were solitary,3 cases occurred in the right lung and the other 3 cases occurred in the left lung.The diameter of the lesions ranged from 1.0 cm to 5.1 cm.2 cases showed lobulated shape,4 cases showed round shape.4 cases showed circumscribed margin,2 cases showed blurrmed margin.Furthermore,calcification was detected in 1 case.Conclusion Pulmonary chondroma has some characteristic CT features,including vascular border sign and begonia sign.However,it should be differentiated from pulmonary hamartoma,peripheral lung cancer and sclerosing pneumocytoma.

Diagnostic value of dynamic-extended focused assessment with sonography for trauma in patients with multiple trauma / 中华危重病急救医学

Objective To investigate the diagnostic value of dynamic-extended focused assessment with sonography for trauma (D-EFAST) in patients with multiple trauma in intensive care unit (ICU). Methods A prospective clinical study was conducted. Eighty patients with multiple trauma admitted to ICU of Anhui Provincial Hospital from September 1st, 2014 to December 31st, 2016 were enrolled. Extended focused assessment with sonography for trauma (E-FAST) check was conducted at first, for those who had positive findings diagnosis was confirmed by immediately CT examination or surgical exploration. If it was negative, the patients received E-FAST every morning for 7 days (defined as D-EFAST), for those with positive findings, immediately CT or surgery was performed to clarify the diagnosis. The final clinical diagnosis was used as the "gold standard" to calculate the diagnostic accordance rate of EFAST and D-EFAST examination technique for pneumothorax, pleural effusion, spleen injury, kidney damage, liver damage, gastrointestinal injury, pericardial effusion, bladder rupture, and pancreatic injury, as well as their sensitivity, specificity, positive predictive value, negative predictive value, accuracy rate, and missed diagnosis rate, and the difference between EFAST and D-EFAST was compared. Results There were 4 patients excluded because of death and abandoning treatment, and finally 76 patients were included in the study. The total sensitivity of E-FAST examination technique for pneumothorax, pleural effusion, spleen injury, liver damage, gastrointestinal injury, pericardial effusion, and bladder rupture was 75.9% (66/87), and the specificity was 98.3% (587/597), the positive predictive value was 86.8% (66/76), and the negative predictive value was 96.5% (587/608), the accuracy rate was 95.5% (653/684), and the rate of missed diagnosis was 24.1% (21/87). The most of the delayed injury in patients with multiple trauma occurred at 2-7 days after injury with incidence of 4.8% (33/684). The diagnostic sensitivity of D-EFAST for delayed injury was 98.3% (118/120), the specificity was 99.8% (563/564), the positive predictive value was 99.2% (118/119), the negative predictive value was 99.6% (563/565), the diagnostic accuracy rate was 99.6% (681/684), and rate of missed diagnosis was 1.7% (2/120). When the final clinical diagnosis was set as the "gold standard", D-EFAST technology for the detection rate was 98.3% (118/120) for patients with multiple trauma on organ injury while the detection rate of E-FAST was 75.9% (66/87), with statistical significant difference (P < 0.01), indicating that D-EFAST was better than E-FAST in check of multiple trauma patients with organ injury. Conclusion Although the E-FAST technology can quickly diagnose the multiple trauma patients and win the rescue time for critical patients, multiple trauma patients injured after 2-7 days prone to delayed damage and are difficult to detect, and D-EFAST can be used to find delayed damage earlier, and reduce the misdiagnosis rate of multiple trauma patients.

The role of NLRP3 inflammasome in immune response mechanism of Escherichia coli bloodstream infection / 安徽医科大学学报

Objective To investigate the immune reaction mechanism of NLRP3 inflammsome in the Escherichia coli bloodstream infection. Methods C57BL/6 mouses were injected by caudal vein with Escherichia coli and phosphate buffer ( PBS) respectively as injected group and control group. The infected group mice were executed after 24 hours and 48 hours,and the control group mice were executed at the beginning of experiment,taking the tis-sue samples of the two groups and detecting the changes of each index. The changes of the indexes were detected by enzyme-linked immunosorbent assay( ELISA) , real-time quantitative PCR ( RT-qPCR) , Western blot and HE stai-ning. Results Significant inflammatory cell infiltration and tissue necrosis were observed by HE staining in 24 h and 48 h after infection with Escherichia coli. The IL-1β and IL-18 cytokines in tissue homogenate and serum of bloodstream infection group were all increased significantly. The mRNA expression of NLRP3, ASC and caspase-1 in liver and lung homogenate increased significantly at 24 h after infection, while NLRP3, ASC and caspase-1 mR-NA in kidney homogenate increased significantly at 48 h after infection. The expression of NLRP3 protein and ASC protein in the liver, lung and kidney tissues of the 48 h group was significantly higher than that in the 24 h group, but there was no significant difference in pro-caspase-1 expression of liver and kidney tissues between three groups. The expression of NLRP3 protein and ASC protein in liver, lung and kidney tissues in 48 h group was significantly higher than that in 24 h group,the expression of pro-caspase-1 protein in liver and kidney tissue in three groups dis-played no significant difference,the expression of caspase-1 protein in lung and kidney tissues was increased with time. Conclusion Escherichia coli bloodstream infection is associated with the activation of NLRP3 inflammatory, and the expression level of NLRP3 inflammasome was related to the severity of infection, with the increase of infec-tion, NLRP3 inflammatory expression increased. The findings may provide a new idea for the treatment of sepsis caused by Escherichia coli bloodstream infection.

Bonding strength of resin and tooth enamel after teeth bleaching with cold plasma / 北京大学学报(医学版)

Objective:To investigate the immediate bond strength and surface structure of resin and the tooth enamel which treated by cold plasma.Methods:In the study,40 bovine incisors were divided into two equal parts.In this sense,all enamel adhesive samples were prepared and then randomly divided into 4 groups(n =20).group 1:acid +single bond 2 +resin composite(control group);group 2:beyond bleaching+acid+single bond 2+resin composite;group 3:treated by cold plasma for 5 minutes+acid+single bond 2+resin composite;group 4:treated by cold plasma for 5 minutes+single bond 2+resin composite.Single bond 2 bonding system and Filtek Z250 resin were used in this experiment.The shear bond strength was tested by universal testing machine.The surface of the enamel in different processes was observed by scanning electron microscope (SEM).Statistical analyses by the single factor analysis of variance and multiple pairwise comparisons were performed with SPSS 1 7 .0 .Results:The shear bond strength of group 4 (8.60 MPa)was significantly lower than that of the other three groups (P<0.05). The shear bond strength of group 2 (1 7.89 MPa)was higher than that of group 4,but lower than group 1 and group 3 (P<0.05).There was no significant difference between group 1 (34.82 MPa)and group 3 (34.69 MPa).Scanning electron microscope indicated that the enamel treated by cold plasma had slight molten form,which was different from etched enamel surface.The fractured surface of group 3 was mix fracture,which was similar to the control group (group 1 ).Conclusion:Compared with the conven-tional clinic bleaching,immediate bond strength of resin-enamel that treated by cold plasma has not been affected.