Objective To explore the application value of dual-energy computed tomography(DECT)of the chest combined with enhanced MRI of the brain in predicting anaplastic lymphoma kinase(ALK)gene mutation in patients with brain metastasis of lung adenocarcinoma.Methods The clinical and imaging data of 77 patients with brain metastasis of lung adenocarcinoma were analyzed retrospectively.Clinical data and DECT parameters of chest,enhanced MRI images of brain and ALK gene mutation status were included.And the quantitative parameters of DECT included normalized iodine concentration in arterial phase(NICA),normalized iodine concentration in venous phase(NICV),λ in arterial phase(λA)and λ in venous phase(λV).According to the ALK gene detection results,they were divided into ALK positive group(n=17)and ALK negative group(n=60).The differences of clinical data,DECT parameters,and MRI images between the two groups were compared,and the logistic regression model for predicting ALK gene mutation was constructed.The prediction of the model was evaluated by receiver operating characteristic(ROC)curve and area under the curve(AUC).Results Univariate analysis revealed that ALK positive were found in youngers and non-smokers.λV and NICV in ALK positive group were significantly lower than those in ALK negative group.The peritumoral brain edema index(PBEI)and peritumoral brain edema size(PBES)of ALK positive group were significantly smaller than those of ALK negative group.There was statistically significant in age,smoking history,λV,NICV,PBEI and PBES between the two groups(P＜0.05).Clinical features combined with DECT parameters were used to establish model 1,clinical features combined with DECT parameters and MRI parameters were used to establish model 2.Model 2 was significantly superior to model 1 or univariate analysis,respectively,in predicting ALK gene mutation by DeLong test,the AUC was 0.927.Conclusion ALK mutations are more common in youngers and non-smokers.λV,NICV,PBEI,and PBES are reliable predictors of ALK mutations.Model 2 can improve predictive efficiency significantly.

Objective To explore the application value of dual-energy computed tomography(DECT)of the chest combined with enhanced MRI of the brain in predicting anaplastic lymphoma kinase(ALK)gene mutation in patients with brain metastasis of lung adenocarcinoma.Methods The clinical and imaging data of 77 patients with brain metastasis of lung adenocarcinoma were analyzed retrospectively.Clinical data and DECT parameters of chest,enhanced MRI images of brain and ALK gene mutation status were included.And the quantitative parameters of DECT included normalized iodine concentration in arterial phase(NICA),normalized iodine concentration in venous phase(NICV),λ in arterial phase(λA)and λ in venous phase(λV).According to the ALK gene detection results,they were divided into ALK positive group(n=17)and ALK negative group(n=60).The differences of clinical data,DECT parameters,and MRI images between the two groups were compared,and the logistic regression model for predicting ALK gene mutation was constructed.The prediction of the model was evaluated by receiver operating characteristic(ROC)curve and area under the curve(AUC).Results Univariate analysis revealed that ALK positive were found in youngers and non-smokers.λV and NICV in ALK positive group were significantly lower than those in ALK negative group.The peritumoral brain edema index(PBEI)and peritumoral brain edema size(PBES)of ALK positive group were significantly smaller than those of ALK negative group.There was statistically significant in age,smoking history,λV,NICV,PBEI and PBES between the two groups(P＜0.05).Clinical features combined with DECT parameters were used to establish model 1,clinical features combined with DECT parameters and MRI parameters were used to establish model 2.Model 2 was significantly superior to model 1 or univariate analysis,respectively,in predicting ALK gene mutation by DeLong test,the AUC was 0.927.Conclusion ALK mutations are more common in youngers and non-smokers.λV,NICV,PBEI,and PBES are reliable predictors of ALK mutations.Model 2 can improve predictive efficiency significantly.

Objective To discuss the value of the multi-parameter imaging of dual-energy computed tomography(DECT)combined with apparent diffusion coefficient(ADC)value of brain metastases in predicting lung adenocarcinoma with epidermal growth factor receptor(EGFR)gene mutation.Methods The DECT and MRI parameters of 90 patients with lung adenocarcinoma and brain metastases were collected.DECT parameters included normalized iodine concentrations in the arterial and venous phases(N1CA,NICV)and slope of the energy spectrum curves in the arterial and venous phases(kA,kv).The MRI parameters of brain metastases included ADC and relative ADC(rADC)of solid area,necrotic area,and peritumoral edema.Predictive model were constructed for EGFR gene mutation according to the parameters above.Results NICV,kv,ADC and rADC of solid area and peritumoral edema in the EGFR positive group were higher than those in the EGFR negative group,which had statistical significances(P＜0.05).Model1 and model2 were established by combining DECT or MRI parameters,while model3 was established by combining DECT and MRI parameters,which had the best predictive efficiency for EGFR gene mutation,with an area under the curve(AUC)of 0.846.Conclusion The predictive model combining DECT parameters with ADC value of brain metastases can improve the prediction efficiency of EGFR gene mutation in advanced lung adenocarcinoma.

Objective To discuss the value of the multi-parameter imaging of dual-energy computed tomography(DECT)combined with apparent diffusion coefficient(ADC)value of brain metastases in predicting lung adenocarcinoma with epidermal growth factor receptor(EGFR)gene mutation.Methods The DECT and MRI parameters of 90 patients with lung adenocarcinoma and brain metastases were collected.DECT parameters included normalized iodine concentrations in the arterial and venous phases(N1CA,NICV)and slope of the energy spectrum curves in the arterial and venous phases(kA,kv).The MRI parameters of brain metastases included ADC and relative ADC(rADC)of solid area,necrotic area,and peritumoral edema.Predictive model were constructed for EGFR gene mutation according to the parameters above.Results NICV,kv,ADC and rADC of solid area and peritumoral edema in the EGFR positive group were higher than those in the EGFR negative group,which had statistical significances(P＜0.05).Model1 and model2 were established by combining DECT or MRI parameters,while model3 was established by combining DECT and MRI parameters,which had the best predictive efficiency for EGFR gene mutation,with an area under the curve(AUC)of 0.846.Conclusion The predictive model combining DECT parameters with ADC value of brain metastases can improve the prediction efficiency of EGFR gene mutation in advanced lung adenocarcinoma.

Objective To investigate the effect of sublingual nitroglycerin(NTG)tablets on the quality of computed tomography angiography(CTA)around the knee joint in patients with knee osteoarthritis(KOA).Methods A total of 100 patients with KOA were included in the study and randomly divided into two groups before lower limb CTA(40 cases in the medication group and 60 cases in the control group).The contrast-to-noise ratio(CNR)of CTA images were compared,and the overall image quality and vascular grading were evaluated and compared using the Likert 5-point method.The diameter of the popliteal artery(PA),anterior tibial artery(ATA),posterior tibial artery(PTA),peroneal artery(PeA),descending genicular artery(DGA),lateral superior genicular artery(LSGA),medial superior genicular artery(MSGA),middle genicular artery(MGA),medial inferior genicular artery(MIGA),lateral inferior genicular artery(LIGA),and anterior tibial recurrent artery(ATRA)were measured.Furthermore,the number of visible arteries around the knee joint between the two groups were calculated and compared.Results The CNR and overall CTA image quality of arteries around the knee joint in the medication group were significantly higher than those in the control group(P＜0.05).Moreover,the lumen diameter of the PA and its branches significantly increased in the medication group(P＜0.05).In comparison to control group,the number of visible vessels significantly increased in the medication group(P＜0.05).Conclusion Sublingual administration of NTG during CTA examination can effectively increase arterial diameter around the knee joint,resulting in improved image quality as well as an increased number of visible arteries.