510(k) · Cleared
ClearedTof-Watch
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Organon Teknika Corp. · KOI Stimulator, Nerve, Peripheral, Electric
Cleared on Dec 16, 1997 after a 151-day review. The FDA summary names its predicate without a number. 7 later devices descend from it.
- Decided
- Dec 16, 1997
- Review
- 151 days
- Class
- Class II
- Product code
- KOI
- Recalls
- None
- Predicates
- 0
7 later devices descend from it, 2 citing it directly.
- This deviceK972698 Tof-WatchOrganon Teknika Corp. · 1997
- Descendant · cites it directly · 4 of its ownK172690 ToFscanIdmed · 2018
- Descendant · 2 generations on · 1 of its ownK220530 Tetragraph Neuromuscular Transmission MonitorSenzime AB · 2022
- Descendant · cites it directly · 1 of its ownK172843 TwitchView SystemBlink Device Corporation · 2018
- Descendant · 3 generations on · 0 of its ownK261098 TetraGraph Neuromuscular Transmission Monitor (SEN…Senzime AB · 2026
- Descendant · 2 generations on · 0 of its ownK243339 WiTOFIdmed · 2025
Showing 5 of 7 descendants. See all descendants
Descendants cleared per year
Most influential descendants
Showing 5 of 7 · See all- K172690ToFscanIdmed · 2018 · cites it directly4descendants
- K220530Tetragraph Neuromuscular Transmission MonitorSenzime AB · 2022 · 2 generations on1descendant
- K172843TwitchView SystemBlink Device Corporation · 2018 · cites it directly1descendant
- K261098TetraGraph Neuromuscular Transmission Monitor (SEN 2015)Accessories:TetraSens (SEN…Senzime AB · 2026 · 3 generations on0descendants
- K243339WiTOFIdmed · 2025 · 2 generations on0descendants
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| 0 (this device) | K972698 | Tof-Watch | Organon Teknika Corp. | 1997 | — |
| +1 | K172690 | ToFscan | Idmed | 2018 | — |
| +2 | K220530 | Tetragraph Neuromuscular Transmission Monitor | Senzime AB | 2022 | — |
| +1 | K172843 | TwitchView System | Blink Device Corporation | 2018 | — |
| +3 | K261098 | TetraGraph Neuromuscular Transmission Monitor (SEN 2015)Accessories:TetraSens… | Senzime AB | 2026 | — |
| +2 | K243339 | WiTOF | Idmed | 2025 | — |
Descendants by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2018 | 2 | 0 |
| 2019 | 1 | 0 |
| 2022 | 1 | 0 |
| 2024 | 1 | 0 |
| 2025 | 1 | 0 |
| 2026 | 1 | 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 KOI? 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 KOI device
- #1 K261098 TetraGraph Neuromuscular Transmission Monitor…score 21.1 · 39 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (2)
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 |
|---|---|---|---|
| * | — | Organon Teknika - TOF-Guard Named without a submission number | |
| * | — | Neuro Technology - Digistim 3 Plus Named without a submission number |
What descends from it? (7)
2 later devices cite it directly; ranked here by how many devices descend from each in turn.
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?
- Of its descendants, K172690 (Idmed, 2018) has gone furthest, with 4 descendants of its own.
How does its category compare?
All KOI devicesKOI Stimulator, Nerve, Peripheral, Electric: FDA decisions, review times, recalls and adverse event reports over 20 years.
FDA decisions per year · KOI
2in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · KOI
174in 2022
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · KOI
No recall names KOI since 2007.
Adverse event reports per year · KOI
5in 2025
MAUDE reports naming product code KOI, 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 | 0 | — | 0 | 0 |
| 2008 | 0 | — | 0 | 0 |
| 2009 | 0 | — | 0 | 0 |
| 2010 | 0 | — | 0 | 0 |
| 2011 | 0 | — | 0 | 1 |
| 2012 | 0 | — | 0 | 3 |
| 2013 | 0 | — | 0 | 2 |
| 2014 | 0 | — | 0 | 9 |
| 2015 | 0 | — | 0 | 1 |
| 2016 | 1 | — | 0 | 0 |
| 2017 | 0 | — | 0 | 0 |
| 2018 | 2 | — | 0 | 1 |
| 2019 | 1 | — | 0 | 4 |
| 2020 | 1 | — | 0 | 4 |
| 2021 | 2 | — | 0 | 3 |
| 2022 | 3 | 174 | 0 | 4 |
| 2023 | 0 | — | 0 | 1 |
| 2024 | 1 | — | 0 | 2 |
| 2025 | 2 | — | 0 | 5 |
| 2026 | 1 | — | 0 | — |
What is it indicated for?
The TOF-Watch device can be used as an objective monitor using accelerometry for measuring the muscle contraction following a stimulation of the respective motorneuron, as a peripheral nerve stimulator (without the objective measuring function) for subjective monitoring and as a nerve location device utilizing a needle electrode.
Indications for use read by OCR from a scanned FDA summary, so letters may be misread. Check the PDF before quoting it.
https://510kreport.com/device/K972698 · printed Nov 6, 2026
Cite this page
510(k) Report. “K972698: Tof-Watch.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K972698
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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