RESUMEN
Objective To evaluate the effectiveness of gamma knife and radioactive effect for glioma.Methods MR images of 106 cases with glioma treated by gamma knife were analysed based on classified.Results The effectiveness of gamma knife was the best for ependyoma and oligodendroglioma,the secondly for astocytoma (Ⅰ～Ⅱ) .The effectiveness for astrocytoma( Ⅲ～Ⅳ)was not well.The effective rate in 1 year after treament for astocytoma(Ⅰ～Ⅱ)was far higher than 2～3 years later.The 2nd year after treatment was the peak time for edema around tumor and the special radioactive contrast enhancement on MR.Conclusion Gamma knife is a effective therapy for glioma,especially for ependyoma,oligodendroglioma and astocytoma(Ⅰ～Ⅱ).The radioactive effect showed as edema and radioactive contrast enhancement on MR can become smaller or disappear 2 years later after treament.