1. Evaluation of localized region-based segmentation algorithms for CT-based delineation of organs at risk in radiotherapy 
Mehdi Astaraki, Mara Severgnini, Vittorino Milan, Anna Schiattarella, Francesca Ciriello, Mario de Denaro, Aulo Beorchia, Hossein Aslian 
Physics and Imaging in Radiation Oncology 
Volume 5, Pages (January 2018)
DOI: /j.phro
Copyright © 2018 The Authors Terms and Conditions

2. Fig. 1
Example of the results from both manual and semi-automatic delineations of an image slice of six OARs. The first column (a1, b1, c1, d1, e1, f1) represents the initial contours defined by two experienced users and the final semi-automatic results; the second column (a2, b2, c2, d2, e2, f2) represents the manual contours defined by three oncologists (red, oncologist 1; yellow, oncologist 2; cyan, oncologist 3), demonstrating the inter-observer variability in the OAR delineation. The last column (a3, b3, c3, d3, e3, f3) shows a contour overlap of the semi-automatic (magenta) results, and the average of the oncologists’ contours (blue). All image datasets were exported from the PACS at a university hospital of Trieste, Italy. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Physics and Imaging in Radiation Oncology 2018 5, 52-57DOI: ( /j.phro )
Copyright © 2018 The Authors Terms and Conditions

3. Fig. 2
(a) Difficulty in simultaneously segmenting the femoral head and pelvic bone, and (b) a lack of distinct boundaries between the rectum and nearby structures (manual contour, blue; semi-automatic contour, magenta). (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)
Physics and Imaging in Radiation Oncology 2018 5, 52-57DOI: ( /j.phro )
Copyright © 2018 The Authors Terms and Conditions