ESTRO 2024 - Abstract Book

S3931

Physics - Image acquisition and processing

ESTRO 2024

characteristics of CBCTs were quantified using the water phantom scan by calculating the modulation transfer function (MTF), standard deviation (SD) and noise power spectrum (NPS).

Results:

Figure 1 presents a visual comparison of projections and reconstructed images of CBCT HR , CBCT SR , CBCT BI and CBCT LR . CBCT SR resulted in the best image similarity metrics with a MAE of 55 HU (CBCT BI : 59 HU, CBCT LR : 60 HU), a ME of 4 HU (CBCT BI : 7 HU, CBCT LR : 13 HU), a PSNR of 43.5 dB (CBCT BI : 41.9 dB, CBCT LR : 42.0 dB) and a DSC of 0.93 (CBCT BI : 0.92, CBCT LR : 0.89). For CBCT SR the comparison of rigid registration parameters with the ground truth CBCT HR resulted in mean differences below 0.05° and 0.14 mm, showing high agreement with the reference CBCT HR . For CBCT LR and CBCT BI higher mean differences were observed with values below 0.10°/0.45 mm and 0.06°/0.24 mm respectively.