“Evaluation of a combined respiratory‐gating system comprising the TrueBeam linear accelerator and a new real‐time tumor‐tracking radiotherapy system: A preliminary study” [JACMP, 17(4), 2016]

After the publication of the manuscript titled “Evaluation of a combined respiratory‐gating system comprising the TrueBeam linear accelerator and a new real‐time tumor‐tracking radiotherapy system: a preliminary study”1, an error was discovered in measured delay time (Δt_gate‐on) and Table 1 (Δt_beam‐on).

Table 1.

Comparison of delay times of various respiratory gating systems

Author	modality	▵tbeam‐on (ms)	▵tbeam‐off (ms)
Chang et al.(19)	Novalis Tx + ExacTrac	200 ± 30
	Novalis Tx + RPM	90 ± 10
Smith et al.(20)	Trilogy + Calypso	75.0 ± 12.7	65.1 ± 12.9
Woods et al.(21)	TrueBeam + RPM	139 ± 10
AAPM TG142(22)		100	100
This study	TrueBeam + SyncTraX
	6 MV‐FF	109.5 ± 11.8	71.5 ± 12.1
	6 MV‐FFF	115.9 ± 12.1	62.7 ± 14.1
	10 MV‐FF	103.5 ± 8.6	68.1 ± 7.2
	10 MV‐FFF	112.1 ± 15.3	69.0 ± 10.7

RPM, real‐time positioning management; FF, flattened; FFF = flattening‐filter‐free.

The incorrected data have been removed from the results. Additionally, correct data have been added to generate a new Table 1 (shown below). The specific values for Δt_gate‐on and Δt_beam‐on have got smaller, but all of the original findings and conclusions remain valid.

The new corrected table 1 values have resulted in the following changes (bold italics) to the text of the manuscript.

Abstract

The total time delay between TrueBeam and SyncTraX was <200 ms for each photon beam.

Results

B. Evaluation of time delay using oscilloscope

The mean ± SD values of Δt_gate‐on were 64.2 ± 11.6 ms, 70.3 ± 12.2 ms, 58.3 ± 8.6 ms, and 66.4 ± 15.4 ms in the case of 6 MV‐FF, 6 MV‐FFF, 10 MV‐FF, and 10 MV‐FFF photon beams, respectively.

For each photon beam, Δt_beam‐on + Δt_beam‐off <200 ms.

Discussion

In this study, the time delay was measured using an oscilloscope, and the total time delay was <200 ms for each photon beam.