The Value Of Functional Magnetic Resonance Imaging In Differential Diagnosis Of Benigh And Malignant Pulmonary Nodules Or Masses

The first part Differential Diagnosis of Benign and Malignant Pulmonary Nodules or Masses by Incoherent Motion Diffusion-weighted Imaging in Magnetic Resonance ImagingObjective:To evaluate images of incoherent motion within voxels,analyze the IVIM parameters of benign and malignant nodules or masses in the lungs,and analyze the differential diagnostic value between IVIM parameters among different pathological types of lung cancer.It provides certain imaging support for clinical practice to judge the benign and malignant nodules or masses in the lung and different pathological types of lung cancer.Methods:This study was a prospective study.A total of 29 patients with solid pulmonary nodules or masses found on chest CT in our hospital from November 2017 to December 2018 were collected,with a total of 41lesions.Among them,there were 12 intrapulmonary benign lesions and 29intrapulmonary malignant lesions,which were confirmed by pathological biopsy or clinical treatment.All patients underwent a 3.0T superconducting magnetic resonance scanner for inspection and imaging.The obtained image data was uploaded to the 4.6 version of the image post-processing workstation.The lesions of interest（ROI）were manually drawn by two measurers and record the mean of both measurements.Analysis of T1-weighted,T2-weighted and IVIM image signal characteristics of benign and malignant nodules or masses in the lung.Divided into benign and malignant lung lesions groups and different pathological types of lung cancer groups,the differences in IVIM parameters（StangardADC,SlowADC,FastADC,f）were compared within the group;The diagnostic performance of each parameter in the benign group and the malignant group was compared,and the optimal cut-off value,sensitivity and specificity of lung cancer were obtained.The SPSS 22.0 statistical software was used.Results:（1）In the benign lesion group,the StandardADC value and the SlowADC value were larger than those in the malignant lesion group,and the results were significantly different（P<0.05）.The values of FastADC and f in the benign lung lesions were not significantly different from those in the malignant lesions group（P>0.05）.（2）The SlowADC value is the most effective in the diagnosis of benign and malignant lung lesions.The area under the ROC curve（AUC）is 0.974,and the optimal cutoff value is 0.883×10^-3mm²/s.The corresponding sensitivity and specificity are 0.917 and 0.966,respectively.（3）There were significant differences in the values of StandardADC and SlowADC between the adenocarcinoma group,the squamous cell carcinoma group and the small cell lung cancer group.Pairwise comparison showed that the adenocarcinoma group had higher StandardADC value and SlowADC value than the squamous cell carcinoma and small cell lung cancer group,and the difference was significant（P<0.05）.There were no significant differences in FastADC values and f values between the three groups（All P>0.05）.Conclusion:1 The StandardADC value and SlowADC value of the IVIM parameters contribute to the differential diagnosis of benign and malignant lesions in the lung.Malignant lesions in the lungs have lower StandardADC values and SlowADC values than benign lesions.The SlowADC has the highest diagnostic performance,and the optimal cutoff value is 0.883×10^-3mm²/s.2 IVIM parameters of Standard ADC and SlowADC have certain significance in differentiating lung adenocarcinoma,squamous cell carcinoma and small cell lung cancer,and provide imaging support for differentiating different pathological types of lung cancer.The second part Dynamic contrast-enhanced magnetic resonance in the differential diagnosis of different pathological types of lung cancer Objective: Evaluation of dynamic contrast-enhanced magnetic resonance（DCE-MRI）scan,differential diagnosis of different pathological types of lung cancer by time signal intensity curve and DCE-MRI parameters,providing some imaging support for differential diagnosis between different pathological types of lung cancer in clinical practice.Methods: This study was a prospective study.A total of 29 malignant lesions were found in 27 patients with solid pulmonary nodules or masses on chest CT in our hospital from November 2017 to December 2018,all of which were confirmed by pathology.All cases were imaged by a 3.0T superconducting magnetic resonance scanner,and the obtained image data was uploaded to the 4.6 version of the image post-processing workstation.The lesion area of interest（ROI）was manually plotted by two measurers separately and record the mean of both measurements.Comparison of time signal intensity curve and DCE-MRI parameters(K^trans,K_ep,V_e)for differential diagnosis of different pathological types of lung cancer.Results:（1）Among the 12 squamous cell carcinoma lesions,the number of A,B and C type TIC curves was 8,2 and 1,respectively.In the 8 small cell lung cancer lesions,the number of A,B and C type TIC curves was 5,2 and 1,respectively.The number of A,B and C types of TIC curves in 9 adenocarcinoma lesions was 5,1 and 3,respectively.（2）The K^trans value of adenocarcinoma group was significantly larger than that of squamous cell carcinoma and small cell lung cancer group,the K_ep value of adenocarcinoma group was significantly higher than that of small cell lung cancer group,all with statistically significant differences（P<0.05）.There was no significant difference in the K_ep value between the adenocarcinoma group and the squamous cell carcinoma group.There were no significant differences in the parameters of K^trans and K_ep between the squamous cell carcinoma group and the small cell lung cancer group.There was no significant difference in the parameter of V_e values between the three groups（all P >0.05）.Conclusion: 1 The TIC curve of DCE-MRI has certain difficulties in identifying the vascular distribution and perfusion characteristics of lung cancer tumors of different pathological types.There were some overlaps in the A,B,and C patterns of TIC curves between different pathological types of lung cancer.2 The parameters of DCE-MRI,K^trans and K_ep,have different significance in the differential diagnosis of different pathological types of lung cancer,and provide imaging support for different pathological types of lung cancer.