ESTRO 2022 - Abstract Book

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Abstract book

ESTRO 2022

1.3.0 (Limbus AI Inc.), and Admire v. 3.28 (prototype by Elekta) software. The type and number of contours automatically contoured by the three software are different. Lymph nodes were not evaluated. For the Pelvis, we also compared the performances of AI-based with atlas-based segmentation approaches. For this purpose two MIM atlases: a proprietary atlas (High-Risk Prostate, HRP) and an in-house developed atlas (AOUC) [1] were employed, invoking them from an in-house, multi-subject customized workflow, in which registration parameters and post-processing options were optimized.

Each contour (including manual) was visually evaluated in a blinded test by a Radiation Oncologist (RO) (other than the reference one), assigning a score proportional to the degree of corrections needed for clinical suitability: 0 (contour acceptable without editing); 1 (minor revision required); 2 (further revision needed). Results For each district, the percentage of evaluated structures scored 0, 1 or 2 are reported in figure 2a. The percentage of evaluated structures for which no corrections or minor corrections were needed are reported in fig. 2b.

For all districts, more than 79% of DL contours are acceptable or need minor corrections (Fig. 2b). DL contours generally have a higher degree of clinical acceptability than atlas-based contours. Although certain atlas-based contours sometimes require even major revision, we improved MIM HRP atlas contours quality by optimizing the workflow