The aim of the study was to improve local control and long-term survival in children with medulloblastoma, reduce the side effects of treatment and improve quality of life.

The technical advantages of Tomotherapy HD in the radiotherapy of children medulloblastoma (advantages in clinical operation and physics) were transformed into clinical advantages, and the possible mechanisms were explored.

Inclusion Criteria:

• The patient was diagnosed as myeloblastoma by surgical pathology with definite pathological classification. MRI of the head and spinal cord before and after operation, with definite staging; Radiotherapy was performed within 28 days after surgery.

Exclusion Criteria:

• Previous radiotherapy in the whole brain, whole spinal cord or primary focus; Postoperative radiotherapy for more than 28 days.