A Study On The Delineation Of Target Area Of Central Lung Cancer Of Obstructive Pneumonia With Functional MRI

Objective: To explore the clinical value of magnetic resonance imaging in the radiotherapy target volumes for patients with NSCLC,especially with obstructive pneumonia patients.Methods: From September 2017 to December 2017,18 patients in our hospital who had not been treated with chemotherapy were scheduled to receive radical surgery for lung cancer.All patients received contrast-enhanced chest CT and chest MRI before surgeries.The images of CT,T1 WI,T2WI and DWI were collected.The images were uploaded to the MIM system for image delineation.GTVCT,GTVT1 WI,GTVT2WI,and GTVDWI were compared with pathological tumor volume.The data of CT and MRI diagnose lymphatic node numbers were compared to pathological results.Data were analyzed by using SPSS19.0 statistical software.Results: 1.Using paired comparison methods between CT,T1 WI,T2WI,DWI and pathological results,the mean difference of CT was 11.46,the mean difference of T1 WI was 4.94,the mean difference of T2 WI was5.11,and the mean difference of DWI was 1.69.The comparison with analysis of variance among four groups showed that the difference value between the four detection methods and pathological detection results had a statistics significance(P<0.001).The LSD method was used to compare the four groups.The results showed that there was no statistic significant differences between T2 WI and TIWI(P>0.05).The rest of indexes had statistics significance differences between the two groups(P<0.05).GTVDWI was the closest to GTVP,and was far better than GTVCT.2.Counting the number of lymphatic metastases diagnosed by CT and MRI and the number of positive pathological lymphatic metastasis among18 patients.2 8 cases were metastatic lymphatic nodes diagnosed by CT.And 29 cases were metastatic lymphatic nodes and 30 cases were metastasis positive pathological lymphatic nodes diagnosed by MRI.3cases were missed diagnosed and one case was misdiagnosed positive lymphatic nodes by CT.There were 3 missed diagnosis and 2 misdiagnosis positive lymphatic nodes from MRI.The specificity and sensitivity of CT diagnosis of metastatic lymphatic nodes were 90% and 90%,respectively.The specificity and sensitivity of MRI diagnosis of metastatic lymphatic nodes were 80% and the sensitivity was 90%.The CT and MRI were used to test the area under the curve of lymphatic node metastasis,which showed that the area under the curve was 0.900 and 0.850.The difference had no statistical significance(P=0.500).Conclusions: 1.Functional MRI contrast enhanced CT can better distinguish between lumps and obstructive pneumonia,which can guide the target area more accurately.2.DWI-MRI can be used as an imaging diagnostic method for lung cancer N-stage.