Relationship Between MRI Features And Tumor Angiogenesis In Astrocytomas

Objective: To explore the correlation of MRI features with tumor angiogenesis and tumor malignant degree in strocytomas. Methods: Forty-four cases of astrocytoma proved by surgery and pathology were examined with MR system before operation,monoclonal antibody CD31 was expressed through immunohistochemical staining by means of SP method. Tumor micro vessel density (MVD) were examined by search for the best stained area under low power lens, and then change into high power lens to select three different visual field,and calculates the average. The SIEMENS 0.2T common conduct Magnetom Open viva was used,transversal and agittal orientation have been scanned as routine methods and coronal scan were performed in partial cases. SE T1 weighted imaging(TR/TE=420.0/15.0ms)and SE T2 weighted imaging(TR/TE=6000.0～6285.0/134.0ms) were obtained, and contrast enhancement imaging obtained by injecting Gd-DTPA(0.1mmol/kg) through cubital vein. Tumor size, range of peritumoral edema grade (0 degree: No significant edema or disappear of gyrus only.Ⅰdegree: The width of edema smaller than 2cm, Ⅱ: The width of edema bigger than 2cm but not overtake median line, Ⅲ: The width of edema overtake median line to opposite hemisphere of the brain.), tumor necrosis,contrast enhancement degree and the tumor margin shapes were measured with MRI. Result: 1.As the pathological grade of astrocytoma increased, MVD value was more higher (P<0.05). 2.The extent of peritumor edema showed by MRI was closely correlated with MVD. As extent of peritumor edema increased, MVD value was more higher(P<0.05). 3.There was no significant difference of MVD value in varies tumor size (P>0.05). 4.As the extent of contrast enhancement increased, MVD value was more higher(P<0.05). 5.The MVD value was lower relatively in these tumor of good margins than that of petal shape or faveolate shape, although there wasno　significant difference(P>0.05). Conclusion: It is closely correlative the MRI features with MVD　value in astrocytomas. MRI Features could reflect the biological behavior of astrocytoma as well as the grade of micro vessel hyperplasia indirectly, and have significant value in evaluate the biological behavior of astrocytoma...