Accuracy Evaluation of Collapsed Cone Convolution Superposition Algorithms for the Nasopharynx Interface in the Early Stage of Nasopharyngeal Carcinoma

Table 2

Dosage measured by TLD-100 and GR-200F for IMRT, VMAT, and tomotherapy at the air-tissue interface.

	Position	TPS calculation (cGy)	TLD-100 measurement (cGy)	GR-200F measurement (cGy)	TLD-100 difference (%)	GR-200 difference (%)
IMRT	1	167.8			−3.9	0.7
	2	208.0			−2.8	0.4
	3	184.6			1.8	1.5
	4	167.1			−1.0	1.1
	5	198.7			−0.5	−4.2
	QM				2.3	2.1
VMAT	1	169.1			2.5	4.4
	2	207.3			3.2	5.8
	3	190.0			1.2	4.1
	4	169.2			−0.5	0.7
	5	202.2			2.9	3.1
	QM				2.3	4.0
Tomotherapy	1	171.6			−3.3	−4.3
	2	204.1			−1.4	2.8
	3	188.4			−2.3	1.0
	4	156.03			−3.8	0.6
	5	185.6			−3.9	4.6
	QM				3.1	3.1