Room: AAPM ePoster Library
Purpose: To evaluate the accuracy and effectiveness of .Decimal’s 3D Scanner device used for creating custom electron cutouts including projecting onto curving anatomy and different skin tones.
Methods: The 3D scanner utilizes an infrared based depth scanner in order to create 3D renderings of a scene. Various cutouts were scanned directly in a 2D planar geometry and then ordered. The resulting cutout shapes were then compared back to the ground truth geometry for accuracy. Existing cutouts were projected onto a phantom with curving anatomy. The resulting cutouts were then compared to the original for accuracy. The scanner was also tested on both black, brown and white surfaces to test its ability to render multiple skin types accurately by projecting existing cutouts and comparing the result as above. Angle prediction was tested by printing cutouts from the treatment planning system at 0 gantry, 0 collimator and 0 table and then digitizing the result and comparing the predicted angles.
Results: The 3D scanner device was found to accurately reproduce desired cutout geometries under a variety of conditions. These conditions include curving heterogonous anatomy and both black and white surfaces. Resulting cutouts were within +/- 2 mm of expected results with some error being the result of human drawing variation. The software also predicts setup angles and it was found these angles to be accurate to within +/- 3 degrees.
Conclusion: .Decimal’s 3D scanner device is capable of designing a cutout with the need for using a treatment table within clinically acceptable margins. The conventional method of drawing on a cutout projecting onto a patient’s skin is cumbersome and uses valuable machine time. The 3D scanner provides an accurate replacement that does not require machine time by predicting the field geometry.
Funding Support, Disclosures, and Conflict of Interest: This research was supported by .decimal in the form of free cutouts during testing of the 3D Scanner.
Electron Therapy, Treatment Planning, Irregular Fields
TH- External Beam- Electrons: dose optimization and planning