Initial clinical evaluation of a novel combined biometric, radio-frequency identification, and surface imaging system

To evaluate and characterize the overall clinical functionality and workflow of the newly released Varian Identify system (version 2.3).

Three technologies included in the Varian Identify system were evaluated: patient biometric authentication, treatment accessory device identification, and surface-guided radiation therapy (SGRT) function. Biometric authentication employs a palm vein reader. Treatment accessory device verification utilizes two technologies: device presence via Radio Frequency Identification (RFID) and position via optical markers. Surface-guidance was evaluated on both patient orthopedic setup at loading position and surface matching and tracking at treatment isocenter. A phantom evaluation of the consistency and accuracy for Identify SGRT function was performed, including a system consistency test, a translational shift and rotational accuracy test, a pitch and roll accuracy test, a continuous recording test, and an SGRT vs Cone-Beam CT (CBCT) agreement test.

201 patient authentications were verified successfully with palm reader. All patient treatment devices were successfully verified for their presences and positions (indexable devices). The patient real-time orthopedic pose was successfully adjusted to match the reference surface captured at simulation. SGRT-reported shift consistency against couch readout was within (0.1 mm, 0.03⁰). The shift accuracy was within (0.3 mm, 0.1⁰). In continuous recording mode, the maximum variation was 0.2 ± 0.12 mm, 0.03⁰ ± 0.02⁰. The difference between Identify SGRT offset and CBCT was within (1 mm, 1⁰).

This clinical evaluation confirms that Identify accurately functions for patient palm identification and patient treatment device presence and position verification. Overall SGRT consistency and accuracy was within (1 mm, 1⁰), within the 2 mm criteria of AAPM TG302.