Research of helical tomotherapy for craniospinal radiation

Ojbective: To review the target coverage of helical tomotherapy（HT） plans for craniospinal radiation and its clinical results and side effects.Methods: 2 patients（8-year-old and 18-year-old） with medulloblastoma were treated with tomotherapy.Prescription dose of GTV was 50.6Gy and CTV was 30.6Gy,1.8Gy per fraction.Results: The HT plans demonstrated excellent target coverage,homogeneity and organ sparing.One of the patients completed the treatment successfully except for the haematological radiation injury（grade Ⅱ）;but the other delayed two weeks during the tomotherapy because of the haematological radiation injury（grade Ⅲ） and the eye radiation injury（grade Ⅱ）.Conclusion: The HT plans demonstrate excellent compared with a conventional linear accelerator based craniospinal radiation plan.by the basis of this case study,further evaluation of HT for craniospinal radiotherapy seems justified.