510(k) · Cleared
ClearedHalcyon, Ethos Radiotherapy System
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Varian Medical Systems, Inc. · IYE Accelerator, Linear, Medical
Cleared on Jan 17, 2023 as substantially equivalent to K192377 (Varian Medical Systems, Inc., 2020) after a 113-day review. Its family tree reaches back 16 generations to 2001. 3 later devices descend from it.
- Decided
- Jan 17, 2023
- Review
- 113 days
- Class
- Class II
- Product code
- IYE
- Recalls
- None
- Predicates
- 1
Its longest line of descent runs back 16 generations to K010975 (2001). 62 ancestors in all, the oldest K864886 (1987). 3 later devices descend from it, 1 citing it directly.
- Root · 16 generations backK010975 Eclipse 6.5Varian Medical Systems, Inc. · 2001 · Recalled
- 12 generations between
- 3 generations backK172163 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2017 · Recalled
- 2 generations backK181145 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2018 · Recalled
- 1 generation backK192377 Ethos Treatment Management, Ethos Treatment Planning, Ethos…Varian Medical Systems, Inc. · 2020
- This deviceK222941 Halcyon, Ethos Radiotherapy SystemVarian Medical Systems, Inc. · 2023
- Descendant · cites it directly · 2 of its ownK232113 Halcyon, Ethos Radiotherapy SystemVarian Medical Systems, Inc. · 2023
- Descendant · 2 generations on · 1 of its ownK252977 Halcyon, Ethos Radiotherapy System (5.0)Varian Medical Systems, Inc. · 2026
- Descendant · 3 generations on · 0 of its ownK261856 Halcyon, Ethos Radiotherapy System (5.0)Varian Medical Systems, Inc. · 2026
Show all 16 generations
- Root · 16 generations backK010975 Eclipse 6.5Varian Medical Systems, Inc. · 2001 · Recalled
- 15 generations backK030981 EclipseVarian Medical Systems, Inc. · 2003
- 14 generations backK041403 Eclipse with AaaVarian Medical Systems · 2004
- 13 generations backK050296 Eclipse Treatment Planning SystemVarian Medical Systems · 2005
- 12 generations backK071873 Modification to Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2007 · Recalled
- 11 generations backK073020 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2007 · Recalled
- 10 generations backK091492 Modification to Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2009 · Recalled
- 9 generations backK102011 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2010 · Recalled
- 8 generations backK131891 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2013
- 7 generations backK133247 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2014
- 6 generations backK141283 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2014 · Recalled
- 5 generations backK152393 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2015 · Recalled
- 4 generations backK170969 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2017 · Recalled
- 3 generations backK172163 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2017 · Recalled
- 2 generations backK181145 Eclipse Treatment Planning SystemVarian Medical Systems, Inc. · 2018 · Recalled
- 1 generation backK192377 Ethos Treatment Management, Ethos Treatment Planning, Ethos…Varian Medical Systems, Inc. · 2020
- This deviceK222941 Halcyon, Ethos Radiotherapy SystemVarian Medical Systems, Inc. · 2023
Most influential descendants
Showing 3 of 3 · See all- K232113Halcyon, Ethos Radiotherapy SystemVarian Medical Systems, Inc. · 2023 · cites it directly2descendants
- K252977Halcyon, Ethos Radiotherapy System (5.0)Varian Medical Systems, Inc. · 2026 · 2 generations on1descendant
- K261856Halcyon, Ethos Radiotherapy System (5.0)Varian Medical Systems, Inc. · 2026 · 3 generations on0descendants
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −16 | K010975 | Eclipse 6.5 | Varian Medical Systems, Inc. | 2001 | 3 |
| −15 | K030981 | Eclipse | Varian Medical Systems, Inc. | 2003 | — |
| −14 | K041403 | Eclipse with Aaa | Varian Medical Systems | 2004 | — |
| −13 | K050296 | Eclipse Treatment Planning System | Varian Medical Systems | 2005 | — |
| −12 | K071873 | Modification to Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2007 | 5 |
| −11 | K073020 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2007 | 6 |
| −10 | K091492 | Modification to Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2009 | 2 |
| −9 | K102011 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2010 | 5 |
| −8 | K131891 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2013 | — |
| −7 | K133247 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2014 | — |
| −6 | K141283 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2014 | 1 |
| −5 | K152393 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2015 | 1 |
| −4 | K170969 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2017 | 1 |
| −3 | K172163 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2017 | 1 |
| −2 | K181145 | Eclipse Treatment Planning System | Varian Medical Systems, Inc. | 2018 | 1 |
| −1 | K192377 | Ethos Treatment Management, Ethos Treatment Planning, Ethos Radiotherapy… | Varian Medical Systems, Inc. | 2020 | — |
| 0 (this device) | K222941 | Halcyon, Ethos Radiotherapy System | Varian Medical Systems, Inc. | 2023 | — |
| +1 | K232113 | Halcyon, Ethos Radiotherapy System | Varian Medical Systems, Inc. | 2023 | — |
| +2 | K252977 | Halcyon, Ethos Radiotherapy System (5.0) | Varian Medical Systems, Inc. | 2026 | — |
| +3 | K261856 | Halcyon, Ethos Radiotherapy System (5.0) | Varian Medical Systems, Inc. | 2026 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 1987 | 1 | 0 |
| 1991 | 1 | 0 |
| 1995 | 2 | 0 |
| 1996 | 2 | 0 |
| 1997 | 2 | 0 |
| 1999 | 2 | 0 |
| 2000 | 5 | 0 |
| 2001 | 1 | 0 |
| 2002 | 1 | 0 |
| 2003 | 2 | 0 |
| 2004 | 3 | 0 |
| 2005 | 3 | 0 |
| 2006 | 2 | 0 |
| 2007 | 3 | 0 |
| 2008 | 2 | 0 |
| 2009 | 2 | 0 |
| 2010 | 1 | 0 |
| 2011 | 1 | 0 |
| 2012 | 2 | 0 |
| 2013 | 1 | 0 |
| 2014 | 3 | 0 |
| 2017 | 2 | 0 |
| 2018 | 2 | 0 |
Descendants by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2023 | 1 | 0 |
| 2026 | 2 | 0 |
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
Planning a device in IYE? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new IYE device
- #1 K252977 Halcyon, Ethos Radiotherapy System (5.0)score 18.8 · 18 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (1)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K192377 | Ethos Treatment Management, Ethos Treatment Planning, Ethos Radiotherapy System, HalcyonSummary page 4…21CFR892.5050, IYE, Class II Common/Usual Name: Medical Linear Accelerator Predicate Devices: Halcyon, Ethos Radiotherapy System (K192377) Device Description: Halcyon and Ethos Radiotherapy System are single energy medical linear… | 2020 |
What descends from it? (3)
1 later device cites it directly; ranked here by how many devices descend from each in turn.
| Number | Device | Decided | Descendants |
|---|---|---|---|
| K232113 | Halcyon, Ethos Radiotherapy System | 2023 | 2 |
Has anything in its family been recalled? (0 Class I)
No FDA recall names this device.
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 22 years and passes through 2 companies; a new generation was cleared every 1.3 years on median.
- 40 of the 62 ancestors have a recall of any class.
- Of its descendants, K232113 (Varian Medical Systems, Inc., 2023) has gone furthest, with 2 descendants of its own.
- 1 other device also cites its predicate K192377.
How does its category compare?
All IYE devicesIYE Accelerator, Linear, Medical: FDA decisions, review times, recalls and adverse event reports over 20 years. 2023, this device’s year, is highlighted.
FDA decisions per year · IYE
12in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · IYE
170in 2025
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · IYE
1in 2025
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · IYE
101in 2025
MAUDE reports naming product code IYE, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 23 | 44 | 78 | 155 |
| 2008 | 14 | 69 | 49 | 114 |
| 2009 | 20 | 63 | 22 | 174 |
| 2010 | 23 | 74 | 27 | 246 |
| 2011 | 11 | 94 | 73 | 280 |
| 2012 | 28 | 106 | 20 | 128 |
| 2013 | 18 | 88 | 11 | 96 |
| 2014 | 20 | 100 | 14 | 124 |
| 2015 | 20 | 108 | 8 | 100 |
| 2016 | 21 | 97 | 7 | 97 |
| 2017 | 23 | 94 | 7 | 125 |
| 2018 | 21 | 58 | 7 | 85 |
| 2019 | 19 | 83 | 2 | 91 |
| 2020 | 20 | 67 | 4 | 74 |
| 2021 | 19 | 86 | 5 | 68 |
| 2022 | 12 | 172 | 3 | 66 |
| 2023 | 18 | 129 | 7 | 128 |
| 2024 | 9 | 239 | 1 | 81 |
| 2025 | 12 | 170 | 1 | 101 |
| 2026 | 14 | 120 | 4 | — |
What is it indicated for?
Halcyon and Ethos Radiotherapy System are 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.
The Halcyon and Ethos Radiotherapy System produce CBCT images that can be used in Image Guided Radiation Therapy, and the simulation and planning for adaptive radiation therapy.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K222941 · printed Nov 4, 2026
Cite this page
510(k) Report. “K222941: Halcyon, Ethos Radiotherapy System.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 4, 2026. https://510kreport.com/device/K222941
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026