The Application Of BOLD-fMRI In The Protection Of Visual Function Area During Postoperative Radiotherapy Of Cerebral Gliomas

Objective To investigate the clinical value of functional oxygen level-dependent functional MRI(BOLD-fMRI)in the visual function protection during postoperative radiotherapy for occipital lobe gliomas.Methods Twenty-eight patients with occipital lobe gliomas,who underwent simulation CT,conventional MRI and BOLD-fMRI before postoperative radiotherapy.The location and scope of the visual cortex,which displayed on the 3D T1 anatomical images,were marked on simulation CT images,and a visual cortex protective radiotherapy plan and a conventional radiotherapy plan were made by intensity-modulated radiotherapy(IMRT)respectively.Evaluated the visual cortex protective radiotherapy program through conformity index,homogeneity index,the maximum,the mean radiation to the PTV and the maximum,the mean radiation to the visual cortex.Results There were no statistical differences between conventional radiotherapy plan and visual cortex protective radiotherapy plan in the conformity index and heterogeneity index(P=0.874,0.602),and both plans ensuring the protection of conventional OARs and effective treatment dose.In the protective radiotherapy plan,the Dmax and Dmean dose of the ipsilateral visual cortex received were decreased by 8.40% and 9.25%,and the contralateral visual cortex received were decreased by 13.26% and 14.77%.Conclusions The visual cortex protective radiotherapy plan,which used BOLD-fMRI as a guide,compared to conventional plan,can be targeted to reduce the visual cortex irradiated dose while ensuring the therapeutic dose,and realize the corresponding functional area protection.