Table 1.

Translation in the LR, AP, and IS directions of the five cervical vertebrae compared to the CBCT reference images taken at the first treatment fraction. Values are expressed as mean (SD) [range].

	Left-right (mm)	Anterior-posterior (mm)	Inferior-superior (mm)
C1	0.1 (0.7) [−1.6 to 1.5]	−0.6 (1.2) [−2.8 to 1.8]	−0.3 (0.8) [−2.2 to 1.4]
C2	0.0 (0.4) [−0.7 to 0.6]	−0.2 (0.4) [−0.9 to 0.8]	0.0 (0.8) [−1.5 to 1.9]
C3	0.1 (0.5) [−1.2 to 0.9]	0.4 (1.2) [−2.0 to 2.2]	0.3 (0.8) [−0.9 to 2.0]
C4	0.2 (1.1) [−2.1 to 2.3]	0.7 (2.2) [−3.5 to 4.4]	0.7 (0.9) [−0.9 to 2.2]
C5	0.1 (1.6) [−2.9 to 3.3]	0.9 (3.2) [−5.0 to 6.5]	0.8 (0.9) [−0.8 to 2.7]