Open AccessComparison of Different Registration Methods on Patient Set-Up Error During Volumetric Modulated Arc Therapy Using Cone-Beam CT Imaging for Lung Cancer
Author(s) -
P Mohandass,
D. Khanna,
T. Kumar,
T Thiyagaraj,
Chandra Saravanan,
Narendra Kumar Bhalla,
Abhishek Puri
Publication year - 2018
Publication title -
journal of global oncology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.002
H-Index - 17
ISSN - 2378-9506
DOI - 10.1200/jgo.18.13500
Subject(s) - image registration , medicine , cone beam computed tomography , nuclear medicine , artificial intelligence , cone beam ct , computer vision , matching (statistics) , imaging phantom , grayscale , computer science , computed tomography , radiology , image (mathematics) , pathology
Background: The three-dimensional image-guided radiation therapy is very important in volumetric modulated arc therapy (VMAT) to enhance accuracy throughout the course of a patient's radiation treatment. The image guidance can ensure the safe administration of prescribed radiation dose to the patient. Aim: This study investigated patient set-up uncertainties based on three different registration methods in cone bean CT (CBCT) using volumetric modulated arc therapy (VMAT) for different clinical sites. Methods: A total of 396 CBCT performed for lung VMAT plan for patient set-up verification as per institution image guidance protocol. The approved CT images were transferred from treatment planning system (TPS) to x-ray volumetric imaging system (XVI) for reference image registration. The set-up errors in mediolateral (ML), craniocaudal (CC) and anterioposterior (AP) direction were determined using grayscale matching between the reference CT image and onboard CBCT images. For the current study, patient set-up verification was performed based on clip-box registration (CBR) for image matching. By considering clip-box registration as a reference, other two registration methods of mask registration (MR) and dual registration (DR) (clip-box and mask) were performed for comparison. To compare three registration methods, systematic error (∑), random error (σ), mean displacement, mean set-up error and maximum error were analyzed. Results: The systemic and random errors were less in clip-box registration as compared with other two registration ( P > 0.05). Similarly, maximum error, mean displacement error and mean set-up errors were observed less in clip-box registration as compared with mask and dual registration ( P > 0.05). However, statically no significant difference was observed between three different registration methods ( P > 0.05). Conclusion: All three registration methods can be used for patient set-up accuracy for lung VMAT plan. However, the current study suggested that clip-box method will be more efficient as compared with mask and dual registration methods.