Realistic three-dimensional information about the compressed breast shape is required for the development of some image processing techniques and improvement of image quality in digital mammography and breast tomosynthesis (DBT). Our aim is to evaluate the precision and accuracy of the breast shape recorded by a structured light (SL) surface scanning system and to examine the similarity between these breast surface scans (BSS) and the depth information contained in the DBT images acquired concurrently, in a cranio-caudal view. Phantom tests were performed to examine the agreement between left- and right-side scans by measuring the estimated length and thickness. To evaluate accuracy, the Hausdorff distance was computed between the scanned phantom and the phantom’s known shape, and also between several measurements performed over time. The agreement between the BSS and the corresponding DBT data was assessed by comparing the width and chest-wall to nipple distance (CND) from both measurements. The phantom analysis found no significant difference between the left- and right-side scans over time for length (p=0.224) and for thickness (p=0.314), and an accuracy of 99.58% and 89.04%, respectively. When comparing the phantom scans over time, a consistent Hausdorff distance of 3.2 mm was found between phantom scans. A significant difference was found for the estimated width when comparing the patient DBT to SL data (p=0.004), but this was not the case for CND (p=0.110). To conclude, the SL scanning system has a high precision and is accurate to within approximately 3 mm compared to the ground truth.
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