open access

Vol 26, No 1 (2021)
Research paper
Published online: 2021-01-22
Submitted: 2021-01-14
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Time motion study to evaluate the impact of flattening filter free beam on overall treatment time for frameless intracranial radiosurgery using Varian TrueBeam® linear accelerator

Gopinath Mamballikalam, Senthilkumar S., Clinto C.O., Ahamed Basith P.M., Jaon bos R.C., Tems Thomas
DOI: 10.5603/RPOR.a2021.0018
·
Rep Pract Oncol Radiother 2021;26(1):111-118.

open access

Vol 26, No 1 (2021)
Original research articles
Published online: 2021-01-22
Submitted: 2021-01-14

Abstract

Background: The aim was to study the impact of the flattening filter free (FFF) beam on overall treatment time for frameless intracranial radiosurgery using TrueBeam® LINAC. The development of frameless stereotactic radiosurgery (SRS) is possible due to the incorporation of image guidance in the delivery of treatment. It is important to analyze the cost and benefits of FFF beams for treating SRS by understanding the impact of FFF beams in reducing the treatment time.

Materials and methods: Dynamic conformal arc (DCA) and volumetric arc therapy (VMAT) plans were generated using 6 MV with a flattening filter (FF) and FFF beams. Overall treatment time was divided into beam on time (BOT) and beam off time (BFT). Percentage beam on time reduction (PBOTR) and Percentage total time reduction (PTTR) factors were defined for the comparison.

Results: BOT reduction was observed to be significant for higher dose per fraction but subjected to the treatment technique and modulation differences. PBOTR values are much higher than PTTR values. The 39.9% of PBOTR resulted in only 8% PTTR for DCA and 65.3% resulted in 15.9% PTTR for VMAT.

Conclusion: Major BFT was utilized for imaging and verification. FFF beam significantly reduced the beam on time and was found to be most effective if the fractional dose was as high as that for SRS. Newly defined PBOTR and PTTR factors are very useful indicators to evaluate the efficacy of FFF beams in terms of time reduction.

Abstract

Background: The aim was to study the impact of the flattening filter free (FFF) beam on overall treatment time for frameless intracranial radiosurgery using TrueBeam® LINAC. The development of frameless stereotactic radiosurgery (SRS) is possible due to the incorporation of image guidance in the delivery of treatment. It is important to analyze the cost and benefits of FFF beams for treating SRS by understanding the impact of FFF beams in reducing the treatment time.

Materials and methods: Dynamic conformal arc (DCA) and volumetric arc therapy (VMAT) plans were generated using 6 MV with a flattening filter (FF) and FFF beams. Overall treatment time was divided into beam on time (BOT) and beam off time (BFT). Percentage beam on time reduction (PBOTR) and Percentage total time reduction (PTTR) factors were defined for the comparison.

Results: BOT reduction was observed to be significant for higher dose per fraction but subjected to the treatment technique and modulation differences. PBOTR values are much higher than PTTR values. The 39.9% of PBOTR resulted in only 8% PTTR for DCA and 65.3% resulted in 15.9% PTTR for VMAT.

Conclusion: Major BFT was utilized for imaging and verification. FFF beam significantly reduced the beam on time and was found to be most effective if the fractional dose was as high as that for SRS. Newly defined PBOTR and PTTR factors are very useful indicators to evaluate the efficacy of FFF beams in terms of time reduction.

Get Citation

Keywords

time motion study; flattening filter free; stereotactic radiosurgery; treatment time; frameless SRS

About this article
Title

Time motion study to evaluate the impact of flattening filter free beam on overall treatment time for frameless intracranial radiosurgery using Varian TrueBeam® linear accelerator

Journal

Reports of Practical Oncology and Radiotherapy

Issue

Vol 26, No 1 (2021)

Article type

Research paper

Pages

111-118

Published online

2021-01-22

DOI

10.5603/RPOR.a2021.0018

Bibliographic record

Rep Pract Oncol Radiother 2021;26(1):111-118.

Keywords

time motion study
flattening filter free
stereotactic radiosurgery
treatment time
frameless SRS

Authors

Gopinath Mamballikalam
Senthilkumar S.
Clinto C.O.
Ahamed Basith P.M.
Jaon bos R.C.
Tems Thomas

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