Alternative fiducial markers for Vero real-time tumor tracking radiotherapy: A phantom study

作者：Park Shin Hyung; Kim Jae Chul^*; Kim Sung Joon

来源：Journal of the Korean Physical Society, 2016, 69(11): 1700-1704.

DOI：10.3938/jkps.69.1700

• Real-time tumor tracking
• Vero
• Fiducial marker
• Respiratory motion
• Four-dimensional image-guided radiotherapy

The objective of this study was to investigate the feasibility of potential fiducial markers consisting of various materials in a Vero real-time tumor-tracking (RTTT) system. In order to determine the applicability of fiducial markers for the Vero RTTT system, we tested various markers consisting of 8 kinds of material (titanium, stainless steel, high-carbon steel, pure steel, copper, silver, tantalum, and gold) with various diameters ranging from 0.3 mm to 1.6 mm and a length of 5 mm. Additionally, a commercial gold coil marker (Visicoil (TM), IBA dosimetry, Schwarzenbruck, Germany) of diameter 0.5 mm and length 1 cm was included for evaluation. The radiologic visibility on kV fluoroscopy/kV CT scan images of the fiducial markers was evaluated. The detectability on the RTTT system was tested using a two-dimensional moving phantom (Brainlab AG, Feldkirchen, Germany), producing sinusoidal motion. The target center's accuracy was evaluated by calculating the deviation of the position of a metal sphere from the center on the dose profile. Dose profiles were measured using Gafchromic EBT2 films (International Specialty Products, NJ, USA). All markers were visible on kV fluoroscopy/kV CT while markers with atomic number ae 25.7 were detectable on the Vero RTTT system. All the detected markers showed excellent geometric accuracy.

• 出版日期2016-12