Building motion models of lung tumours from cone-beam CT for radiotherapy applications

TY - JOUR

T1 - Building motion models of lung tumours from cone-beam CT for radiotherapy applications

AU - Martin, James

AU - McClelland, Jamie

AU - Yip, Connie

AU - Thomas, Christopher

AU - Hartill, Claire

AU - Ahmad, Shahreen

AU - O'Brien, Richard

AU - Meir, Ivan

AU - Landau, David

AU - Hawkes, David

PY - 2013/3/21

Y1 - 2013/3/21

N2 - A method is presented to build a surrogate-driven motion model of a lung tumour from a cone-beam CT scan, which does not require markers. By monitoring an external surrogate in real time, it is envisaged that the motion model be used to drive gated or tracked treatments. The motion model would be built immediately before each fraction of treatment and can account for inter-fraction variation. The method could also provide a better assessment of tumour shape and motion prior to delivery of each fraction of stereotactic ablative radiotherapy. The two-step method involves enhancing the tumour region in the projections, and then fitting the surrogate-driven motion model. On simulated data, the mean absolute error was reduced to 1 mm. For patient data, errors were determined by comparing estimated and clinically identified tumour positions in the projections, scaled to mm at the isocentre. Averaged over all used scans, the mean absolute error was under 2.5 mm in superior–inferior and transverse directions.

AB - A method is presented to build a surrogate-driven motion model of a lung tumour from a cone-beam CT scan, which does not require markers. By monitoring an external surrogate in real time, it is envisaged that the motion model be used to drive gated or tracked treatments. The motion model would be built immediately before each fraction of treatment and can account for inter-fraction variation. The method could also provide a better assessment of tumour shape and motion prior to delivery of each fraction of stereotactic ablative radiotherapy. The two-step method involves enhancing the tumour region in the projections, and then fitting the surrogate-driven motion model. On simulated data, the mean absolute error was reduced to 1 mm. For patient data, errors were determined by comparing estimated and clinically identified tumour positions in the projections, scaled to mm at the isocentre. Averaged over all used scans, the mean absolute error was under 2.5 mm in superior–inferior and transverse directions.

U2 - 10.1088/0031-9155/58/6/1809

DO - 10.1088/0031-9155/58/6/1809

M3 - Article

SN - 0031-9155

VL - 58

SP - 1809

EP - 1822

JO - Physics in Medicine and Biology

JF - Physics in Medicine and Biology

IS - 6

ER -