Room: ePoster Forums
Purpose: To reduce scan uncertainty using compensating materials for transmission and reflection scanning mode when scanning a lens-type dosimeter with a curvature on the flatbed scanner.
Methods: Lens-type dosimeters were fabricated with silicone, the lithium salt of pentacosa-10, 12-diyonic acid (LiPCDA). As the compensating materials, Dragons SkinTM 10, SORTA-ClearTM 40, optical grease, and air (none of the compensating material) were used. The dosimeters were scanned using the reflection and transmission mode with four types of compensating materials spreading on the glass of an Epson 10000XL flatbed scanner. To calibrate the dosimeters, dose was delivered from 0 to 8 Gy. A phantom study was conducted for three plans, and the results were compared with calculated doses using TPS and MC.
Results: Among the compensating materials in the reflection mode, the optical grease showed the highest dose sensitivity and linearity, which are 0.0416 Î”OD/Gy and R2 value of 0.9998 respectively. In phantom study, the dose variation and dose difference showed a good agreement when using the optical grease in reflection mode.
Conclusion: The study found that the optical grease was the most suitable compensating material for the accuracy of dose measurement when scanning the lens-type curved dosimeter on the flatbed, since the dose sensitivity and linearity were enhanced and the dose variation and measurement uncertainty decreased.