Value Of 3.0T Diffusion Tensor Imaging In Differential Diagnosis Of High-grade Gliomas And Brain Metastases

Objective: To explore the diagnostic value of 3.0T MR dispersion tensor imaging techniques for high grade glioma and brain metastases,and to study the differential diagnostic value of DTI techniques for high grade glioma and brain metastases through an isotropic scores and apparent diffusion coefficient in DTI techniques.Methods: To collect 16 cases of high grade glioma and 21 cases of brain metastases confirmed by pathology and follow-up from January2017 to November 2020,retrospective analyzed clinical data,pathological characteristics and magnetic resonance imaging manifestations.For normal MRI flat,enhanced,diffuse weighted imaging and DTI scans,To analyze the imaging features of high grade glioma and brain metastases,And select a region of interest,Including tumor cystic area,tumor parenchyma area,tumor margin area,tumor peripheral edema area,tumor contralateral normal white matter area,the ADC and FA values of different regions of interest in high-grade brain gliomas and brain metastases were compared by measuring FA values in the DTI.Results: 1.clinical and pathological features: among 16 high-grade brain gliomas,12 were anaplastic astrocytoma,2 were anaplastic oligodendroglioma and 2 were glioblastoma.Among 21 cases of brain metastases,the primary tumors included 14 cases of lung cancer,3 cases of breast cancer,2 cases of colon cancer,1 case of esophageal cancer and 1 case of gastric cancer The difference between the two groups was statistically significant in the age of initial diagnosis and the number of lesions(P<0.05),and there was no significant difference in sex composition ratio,shape and location(P>0.05).2.MRI Features:(1)High grade of glioma substance in slightly longer T1、slightly longer T2 signal,DWI sequence is equal or slightly higher signal;the intratumoral cystic degeneration showed long T2 signal,the DWI sequence showed low signal;the peripheral edema showed slightly longer T1、 slightly longer signal,the FLAIR sequence showed slightly higher signal.(2)Brain metastases are substantially slightly longer T1,slightly longer T2 signal,DWI sequence is equal or slightly higher signal;its inner capsule changes long T1、long T2 signal,DWI sequence is low signal;the surrounding tumor edema is slightly longer T1,slightly longer T2 signal,FLAIR sequence is slightly higher signal;enhanced scanning,the tumor substance is wall nodul ar or ring reinforcement,its internal capsule region is not strengthened.3.FA values and ADC results of the same tumor were expressed as mean ± standard deviation.(1)FA value: the FA value in the cystic area of high grade glioma and brain metastases is the lowest,and the highest FA value in the opposite normal brain white matter area of the tumor.The FA values of the parenchymal,cystic,marginal and peripheral edema areas of high grade glioma and brain metastases were lower than those of the normal white matter area of the contralateral side of the tumor(P<0.05).(2)ADC value: the highest ADC value in the internal cystic region of high-grade gli oma and brain metast oma,and the lowest ADC value in the opposite normal brain white matter area of the tumor.The ADC value of high-grade gli oma and brain meta static substance,cystic,marginal,and peripheral edema area increased compared with the opposite normal brain white matter region of the tumor(P<0.05).4.differential diagnosis of high grade glioma and brain metastases in DTI:(1)FA value: the FA value of tumor parenchyma and tumor margin was statistically significant(P<0.05).There was no significant difference in the FA value of tumor cystic area,peri-tumor edema area,tumor contralateral normal white matter area(P>0.05).(2)ADC value:Compared with high-grade gli oma in the same area of interest,the ADC value of the tumor and the area of surrounding tumor edema are statis tically significant(P<0.05).There was no statistical difference in the tumor substance,tumor margin and opposite normal white matter region of the brain(P>0.05).Conclusion: Anaplastic astrocytoma is the most common pathological type of1.high grade glioma,and lung cancer is the most common pathological type of primary tumor of brain metastases.There was a statistical difference in the age of first diagnosis between the two groups of high grade glioma and metastatic tumor,and the age of brain metastases was older.There were statistical differences in the number of lesions,and multiple brain metastases were more common.2.The FA value of high-grade gli oma and brain metast ases in the substantive region,cystic area,marginal area,and peripheral edema area of the tumor decreased compared to the opposite normal white matter area of the tumor,and the ADC value increased compared with the opposite normal white matter area of the tumor.The FA value of the cystic area of high grade glioma and brain metastases was the lowest and the ADC value was the highest.3.two groups of tumor parenchyma area,margin area of the FA value comparison,the tumor internal cystic area,peripheral edema area of the ADC value comparison,there are statistical differences.Diffusion tensor imaging can become a diagnostic and differential diagnostic method of high-grade glioma and brain metastases,assisting in clinical treatment and prognosis.