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Table 2 Summary of daily volumetric and positional data

From: Per-fraction positional and dosimetric performance of prone breast tangential radiotherapy on Halcyon™ linear accelerator assessed with daily rapid kilo-voltage cone beam computed tomography: a single-institution pilot study

Variable

Value, median (range)

Mean ± Stdev

Contour volumes [cc]

  

 Breast PTV Vol

1095.20 (654.20–1343.70)

1040.21 ± 218.26

 Breast PTV Eval Vol

899.90 (540.70–1149.80)

852.00 ± 196.96

Daily couch shift [cm]

  

 LAT

0.07 (− 2.26 to 2.28)

0.05 ± 0.92

 LNG

 − 0.13 (− 2.10 to 1.35)

 − 0.12 ± 0.70

 VRT

 − 0.14 (− 2.20 to 1.93)

 − 0.13 ± 0.63

 MAG

1.08 (0.27–2.78)

1.19 ± 0.57

PTV Eval residual shift [cm]

  

 LAT

 − 0.04 (− 0.35 to 0.32)

 − 0.03 ± 0.12

 LNG

0.07 (− 0.38 to 0.47)

0.05 ± 0.19

 VRT

0.06 (− 0.32 to 0.43)

0.05 ± 0.13

 MAG

0.25 (0.05–0.49)

0.26 ± 0.10

BODY V95% residual shift [cm]

  

 LAT

 − 0.01 (− 0.60 to 0.46)

 − 0.03 ± 0.22

 LNG

 − 0.04 (− 0.53 to 0.66)

 − 0.04 ± 0.18

 VRT

0.05 (− 0.58 to 0.43)

0.03 ± 0.16

 MAG

0.27 (0.04–0.80)

0.30 ± 0.15

Daily SSD [cm]

  

 Lateral beam

85.45 (80.80–95.70)

86.24 ± 3.91

 Medial beam

102.75 (94.70–104.80)

102.00 ± 2.82

 Lateral beam deviation from planned

0.10 (− 2.10 to 1.30)

0.08 ± 0.58

 Medial beam deviation from planned

0.10 (− 0.50 to 1.30)

0.18 ± 0.42

Target contour DSC

  

 Breast PTV Eval

0.93 (0.88–0.97)

0.93 ± 0.02

 BODY V95%

0.92 (0.88–0.96)

0.92 ± 0.02

Patient weight [%]

  

 Deviation from planned/simulation

 − 0.48 (− 6.50 to 4.71)

 − 0.64 ± 2.69

  1. cc, centimeter cubed (cm3); PTV Eval, planning treatment volume for evaluation; LAT, lateral; VRT, vertical; LNG, longitudinal; MAG, magnitude; SSD, source-to-surface distance; DSC, dice similarity coefficient; Stdev, standard deviation