Can audio coached 4D CT emulate free breathing during the treatment course?

TY - JOUR

T1 - Can audio coached 4D CT emulate free breathing during the treatment course?

AU - Persson, Gitte F

AU - Nygaard, Ditte E

AU - Olsen, Mikael

AU - Juhler-Nøttrup, Trine

AU - Pedersen, Anders N

AU - Specht, Lena

AU - Korreman, Stine S

AU - Persson, Gitte F

AU - Nygaard, Ditte E

AU - Olsen, Mikael

AU - Juhler-Nøttrup, Trine

AU - Pedersen, Anders N

AU - Specht, Lena

AU - Korreman, Stine

N1 - Keywords: Adult; Female; Humans; Male; Middle Aged; Respiration; Tomography, X-Ray Computed

PY - 2008/1/1

Y1 - 2008/1/1

N2 - BACKGROUND: The image quality of 4DCT depends on breathing regularity. Respiratory audio coaching may improve regularity and reduce motion artefacts. We question the safety of coached planning 4DCT without coaching during treatment. We investigated the possibility of coaching to a more stable breathing without changing the breathing amplitude. The interfraction variation of the breathing cycle amplitude in free and coached breathing was studied as well as the possible impact of fatigue on longer coaching sessions. METHODS: Thirteen volunteers completed respiratory audio coaching on 3 days within a 2 week period. An external marker system monitoring the motion of the thoraco-abdominal wall was used to track the respiration. On all days, free breathing and two coached breathing curves were recorded. We assumed that free versus coached breathing from day 1 (reference session) simulated breathing during an uncoached versus coached planning 4DCT, respectively, and compared the mean breathing cycle amplitude to the free versus coached breathing from day 2 and 3 simulating free versus coached breathing during treatment. RESULTS: For most volunteers it was impossible to apply coaching without changes in breathing cycle amplitude. No significant decrease in standard deviation of breathing cycle amplitude distribution was seen. Generally it was not possible to predict the breathing cycle amplitude and its variation the following days based on the breathing in the reference session irrespective of coaching or free breathing. We found a significant tendency towards an increased breathing cycle amplitude variation with the duration of the coaching session. CONCLUSION: These results suggest that large interfraction variation is present in breathing amplitude irrespective of coaching, leading to the suggestion of daily image guidance for verification of respiratory pattern and tumour related motion. Until further investigated it is not recommendable to use coached 4DCT for planning of a free breathing treatment course.

AB - BACKGROUND: The image quality of 4DCT depends on breathing regularity. Respiratory audio coaching may improve regularity and reduce motion artefacts. We question the safety of coached planning 4DCT without coaching during treatment. We investigated the possibility of coaching to a more stable breathing without changing the breathing amplitude. The interfraction variation of the breathing cycle amplitude in free and coached breathing was studied as well as the possible impact of fatigue on longer coaching sessions. METHODS: Thirteen volunteers completed respiratory audio coaching on 3 days within a 2 week period. An external marker system monitoring the motion of the thoraco-abdominal wall was used to track the respiration. On all days, free breathing and two coached breathing curves were recorded. We assumed that free versus coached breathing from day 1 (reference session) simulated breathing during an uncoached versus coached planning 4DCT, respectively, and compared the mean breathing cycle amplitude to the free versus coached breathing from day 2 and 3 simulating free versus coached breathing during treatment. RESULTS: For most volunteers it was impossible to apply coaching without changes in breathing cycle amplitude. No significant decrease in standard deviation of breathing cycle amplitude distribution was seen. Generally it was not possible to predict the breathing cycle amplitude and its variation the following days based on the breathing in the reference session irrespective of coaching or free breathing. We found a significant tendency towards an increased breathing cycle amplitude variation with the duration of the coaching session. CONCLUSION: These results suggest that large interfraction variation is present in breathing amplitude irrespective of coaching, leading to the suggestion of daily image guidance for verification of respiratory pattern and tumour related motion. Until further investigated it is not recommendable to use coached 4DCT for planning of a free breathing treatment course.

U2 - 10.1080/02841860802256442

DO - 10.1080/02841860802256442

M3 - Journal article

C2 - 18663648

SN - 0284-186X

VL - 47

SP - 1397

EP - 1405

JO - Acta Oncologica

JF - Acta Oncologica

IS - 7

ER -