The research of different MRI-CT image registration for the stability of radiotherapeutic target delineation on gliomas after surgery / 中国癌症杂志

ABSTRACT

Background and purpose:Accurate target delineation in IMRT setting has been a challenge for post-operative gliomas.The fusion technology with MR+CT image registration could improve the accuracy of target delineation,but there are no reports as to whether this technique could increase the stability of target delineation.This study was to investigate the accuracy of different fusion technologies with MRI+CT image registration so it could improve stability of target delineation of clinical target volume in patients with post-operative gliomas.Methods:The post-operative and pre-operative MRI+CT were registrated in nine patients with post-operative gliomas.Clinical target volume in the two registration images and localized CT images were delineated at 5 different times.The image registration accuracy and stability of target delineation were also quantitatively assessed.Results:The registration accuracy in 3D space was always less than 1.5 mm.The concordance index in CT+MRI(pre-matched),CT+MRI(post-matched)and CT(conv)were(68?9)%,(61?7)% and(41?12)% respectively.The same volumes delineated with three sets of images were(82?7)% for CT+MRI(pre-matched),(78?5)% for CT+MRI(post-matched)and(65?8)% CT(conv),respectively.Conclusions:The volume delineated according to pre-operative MRI registered with CT image have the largest volume and the best stability(P