Fig. 2

Patient setup photograph with a a standard mouthpiece (SMP) and b semi-customized tongue displacement device (SCTDD) for a patient who underwent H&N tomotherapy. Isodose distributions of this patient in the axial section for the c SMP and d SCTDD plans are also shown. The tongue was effectively displaced from the high-dose region near the planning target volume (yellow arrows) by using the SCTDD, while a partial volume of the tongue received a high dose equivalent to the prescribed dose (red arrow) in the SMP plan because SMP only depressed tongue (yellow arrow) without displacing it to the contralateral side of the target