# K181032: Halcyon

- Pathway: 510(k) (Special)
- Applicant: Varian Medical Systems, Inc.
- Decided: May 9, 2018 after 21 days
- Product code: IYE (Accelerator, Linear, Medical)
- Device class: 2
- Regulation: 21 CFR 892.5050
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 12 generations back to K926449 (1995). 36 ancestors in all.
14 later devices descend from it; 3 cite it directly.
0 of 51 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K170817: Halcyon, Varian Medical Systems, Inc. (2017) Summary page 4.

## Most influential descendants
- K192377: Ethos Treatment Management, Ethos Treatment Planning, Ethos Radiotherapy System, Halcyon (2020), 9 descendants of its own
- K212294: Ethos Treatment Management, Ethos Treatment Planning (2021), 4 descendants of its own
- K222941: Halcyon, Ethos Radiotherapy System (2023), 3 descendants of its own
- K232479: ART-Plan (2023), 2 descendants of its own
- K232113: Halcyon, Ethos Radiotherapy System (2023), 2 descendants of its own

## Indications for use
Halcyon is indicated for the delivery of stereotactic radiosurgery and precision radiotherapy for lesions, tumors and conditions anywhere in the body where radiation is indicated for adults and pediatric patients.

Source page: https://510kreport.com/device/K181032
Methodology: https://510kreport.com/methodology