Author: Tsuicheng D. Chiu, Strahinja Stojadinovic, Aaron Thomlinson, You Zhang 👨🔬
Affiliation: Department of Radiation Oncology, UT Southwestern Medical Center, Medical Artificial Intelligence and Automation (MAIA) Lab, Department of Radiation Oncology, UT Southwestern Medical Center, The University of Texas Southwestern Medical Center, University of Texas Southwestern Medical Center 🌍
Purpose: Design and develop an automated verification and validation platform for the Elekta Leksell Gamma Knife (GK) Icon/Esprit High-Definition Motion Management (HDMM) system.
Methods: The HDMM system utilizes an infrared stereoscopic camera, four reference markers integrated with a couch-fixed mask adapter, and a tracking marker placed on the patient’s nose during treatment. The system continuously monitors and measures the movement of the patient marker in relation to the four fixed reference markers and displays the relative values. To verify the accuracy of the HDMM system, an automated, three-axis linear translation platform was designed to simulate patients’ movements during treatments. The structural components of the device were 3D-printed using Polylactic Acid (PLA). Three stepper motors enabled motion, and linear slide rails restrained the movement along each cardinal axis. An Arduino microcontroller was used to generate the pulse sequences that controlled the stepper motors. Open-source firmware and software were used to set up, calibrate, and control the motion of the target along the three axes using standard Geometric Code instructions.
Results: A patient marker was applied to the QA device, which was then firmly attached to the mask adapter. Three single-axis tests with increments of 0.1 mm were performed, followed by a composite three-axis motion test with movements in increments of 0.2 mm. The accuracy of the camera, including both stepwise and cumulative displacements, was assessed by comparing the expected values with those displayed by the HDMM system. The HDMM system accurately measured and displayed the set displacements in both single and multi-axis tests with sub-millimeter precision that meets the requirement of stereotactic radiosurgery treatments.
Conclusion: The HDMM system demonstrated sub-millimeter accuracy in tracking the QA platform's movements. The platform is suitable for both commissioning and routine clinical verification tests of GK HDMM systems.