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Objective:hippocampus-sparing during whole brain radiotherapy poses important challenges with hippocampus contouring and treating plan.we use Linear accelerator-intensity modulated radiotherapy(IMRT)to hippocampus-sparing for patient with brain metastases.Methods:Eight breast cancer patients treated with whole brain radiotherapy with hippocampus-sparing.The hippocampus was contoured,and hippocampus protection regions were expanding a 5mm volumetric around the hippocampus.Linear accelerator IMRT plans with 10 fields were used,the PTV received the prescription dose of 3000cGy in 10 fractions.Result:The mean of PTV V90 and PTV V95 were 99.5%and 98.4%respectively,the homogeneity was 0.09.On average,the hippocampus volume was 5 cm 3,hippocampus protection regions volume was 26.2cm 3,occupying 1.8%.The mean dose of hippocampus and hippocampus protection regions were 17.1Gy and 22Gy,The max dose of hippocampus and hippocampus protection regions were 21.7Gy and 29.3Gy,the mean dose of hippocampus occupied 57%for the prescription dose,the mean dose of hippocampus protection regions occupied 73%for the prescription dose.The max dose of lens were 6Gy.Conclusion:Linear accelerator IMRT allow for protecting of the hippocampus with acceptable target coverage and homogeneity,the neurocognitive was protected.