Radiotherapy Planning, Computer-Assisted 8 Radiotherapy, Intensity-Modulated 8 intensity modulated radiation therapy 8 radiotherapy planning system Article 7 Humans 7 human 7 Radiotherapy Dosage 5 planning target volume 5 radiotherapy dosage 5 clinical article 4 dosimetry 4 treatment planning 4 volumetric modulated arc therapy 4 Phantoms, Imaging 3 Radiotherapy 3 adult 3 comparative study 3 imaging phantom 3 male 3 quality control 3 Aged 2 Head and Neck Neoplasms 2 Radiometry 2 Retrospective Studies 2 VMAT 2 adverse event 2 aged 2 algorithm 2 cancer radiotherapy 2