Image guidance with kilovoltage cone beam computerised tomography (CBCT) has been shown to provide accurate bony and soft tissue setup information [11,12]. Deep-inspiration breath-hold with CBCT is also feasible  and has been integrated as a verification tool for correction protocols when treating patients with ABC . Current CB imaging software allows automatic matching within a user defined region of interest (ROI) but the selected ROI volume is important and can affect image registration accuracy [14–16]. For patients with lung tumours undergoing free-breathing radiotherapy, studies have shown that ROIs centred on the carina and spine can produce accurate CBCT image registration with advanced tumours  whilst soft tissue tumour matching is more accurate with early-staged tumours . With ABC-gated radiotherapy, the optimal automatic registration method for image-guided setup correction has not yet been established. The aim of this study was therefore to evaluate the effect of using four different ROIs (with the Synergy XVI R4.2 software, Elekta, Crawley, UK) with ABC-gated radiotherapy in order to determine the optimum volume for registration.
|Number of pages||4|
|Journal||Acta oncologica (Stockholm, Sweden)|
|Publication status||Published - 25 Nov 2013|
- lung cancer
- cone beam computerised tomography (CBCT)