Open AccessCompensation method for respiratory motion in proton treatment planning for mobile liver cancer
Author(s) -
Jeong Hojin,
Lee Se Byeong,
Yoo Seung Hoon,
Lim Young Kyung,
Kim Tae Hyun,
Park Seyjoon,
Chai Gyu Young,
Kang Ki Mun,
Shin Dongho
Publication year - 2013
Publication title -
journal of applied clinical medical physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.83
H-Index - 48
ISSN - 1526-9914
DOI - 10.1120/jacmp.v14i2.4055
Subject(s) - nuclear medicine , radiation treatment planning , proton therapy , proton , margin (machine learning) , maximum intensity projection , cumulative dose , medicine , computer science , radiation therapy , radiology , physics , quantum mechanics , machine learning , angiography
We evaluated the dosimetric effect of a respiration motion, and sought an effective planning strategy to compensate the motion using four‐dimensional computed tomography (4D CT) dataset of seven selected liver patients. For each patient, we constructed four different proton plans based on: (1) average (AVG) CT, (2) maximum‐intensity projection (MIP) CT, (3) AVG CT with density override of tumor volume (OVR), and (4) AVG CT with field‐specific proton margin which was determined by the range difference between AVG and MIP plans (mAVG). The overall effectiveness of each planning strategy was evaluated by calculating the cumulative dose distribution over an entire breathing cycle. We observed clear differences between AV G and MIP CT‐based plans, with significant underdosages at expiratory and inspiratory phases, respectively. Only the mAVG planning strategy was fully successful as the field‐specific proton margin applied in the planning strategy complemented both the limitations of AVG and MIP CT‐based strategies. These results demonstrated that respiration motion induced significant changes in dose distribution of 3D proton plans for mobile liver cancer and the changes can be effectively compensated by applying field‐specific proton margin to each proton field. PACS numbers: 87.55.D; 87.53.Bn; 87.53.Jw; 87.55.dk