Halcyon, Ethos Radiotherapy System (5.0)

The Halcyon and Ethos Radiotherapy System (5.0) are single-energy medical linear accelerators designed to deliver image-guided radiation therapy and radiosurgery using intensity-modulated and volumetric modulated arc therapy techniques. The system consists of an accelerator and patient support within a radiation-shielded treatment room, plus a control console outside the room. It is indicated for stereotactic radiosurgery and precision radiotherapy for lesions, tumors, and conditions anywhere in the body where radiation is indicated for adults and pediatric patients.

The significant differences from the predicate (version 4.0) are: (1) the new PerfectKinetix dynamic couch adds 6 degrees of freedom (pitch, roll, yaw rotation plus 3 translational movements) for enhanced patient positioning; (2) a Beam Hold Interface with manually added gating flag enabling users to add gating information for compatibility with older software versions; and (3) Customer HASP user group allowing trained hospital personnel to perform preventive and corrective maintenance tasks with restricted system access.

The system complies with IEC 60601-1 and IEC 60601-1-2 for electrical safety and EMC. Additional standards include IEC 60601-2-1 (gantry-based radiation therapy systems), IEC 60601-1-6 (usability), IEC 62304 (software life cycle), IEC 60976 (electron accelerators), IEC 61217 (radiotherapy coordinates and movements), IEC 62274 (record and verify systems), and AAMI RT2:2017 (radiation therapy readiness check).

The predicate device (Halcyon and Ethos version 4.0, K232113) is a legally marketed device with the same intended use as the current version. All technological differences are enhancements rather than fundamental changes in operation. Comprehensive verification and validation testing, including hardware, software, and usability testing, demonstrates that the device is as safe and effective as the predicate, with no discrepancy reports remaining at safety-intolerable or customer-intolerable priority levels.