510(k) · Cleared
ClearedT-Stat Microvascular Tissue Oximeter, Model 303
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
Spectros Corporation · MUD Oximeter, Tissue Saturation
Cleared on Nov 5, 2004 as substantially equivalent to K023938 (Hutchinson Technology, Inc., 2002) and 5 other predicates after a 234-day review. Its family tree reaches back 5 generations to 1993. 67 later devices descend from it.
- Decided
- Nov 5, 2004
- Review
- 234 days
- Class
- Class II
- Product code
- MUD
- Recalls
- None
- Predicates
- 6
Its longest line of descent runs back 5 generations to K931154 (1993). 19 ancestors in all, the oldest K850978 (1985). 67 later devices descend from it, 7 citing it directly.
- Root · 5 generations backK931154 Evis 200 SystemOlympus Corp. · 1993
- 4 generations backK963033 BF 240/P240/IT240 Bronchovideoscope & AccessoriesOlympus America, Inc. · 1996 · Recalled
- 3 generations backK981543 Olympus LF-TP and LF-DP Tracheal Intubation Fiberscopes, Accessories…The Olympus Optical Co. · 1998 · Recalled
- 2 generations backK002231 LF-DP Gastrointestinal and Sigmoid Fiberscope, Accessories and…Olympus Optical Co., Ltd. · 2001
- 1 generation backK011869 Xenf-DP Rhino-Laryngofiberscope, Its Accessories and Ancillary…The Olympus Optical Co. · 2001
- This deviceK040684 T-Stat Microvascular Tissue Oximeter, Model 303Spectros Corporation · 2004
- Descendant · cites it directly · 63 of its ownK051257 Adult Cerebral Oximeter, Model 2040Cas Medical Systems, Inc. · 2005
- Descendant · cites it directly · 59 of its ownK073036 Fore-Sight, MC-2000 SeriesCas Medical Systems, Inc. · 2008
- Descendant · cites it directly · 59 of its ownK061960 Fore-Sight Cerebral Oximeter Monitor, Model 2040Cas Medical Systems, Inc. · 2006
- Descendant · cites it directly · 58 of its ownK083892 Fore-Sight, Model MC-2000 Series (MC-2000, MC-2010, MC2020, MC2030)Cas Medical Systems, Inc. · 2009
- Descendant · cites it directly · 57 of its ownK091452 Fore-Sight, Model MC-2000 Series (MC 2000, MC2010, MC-2020,MC2030)Cas Medical Systems, Inc. · 2009
Showing 5 of 67 descendants. See all descendants
Descendants cleared per year
Most influential descendants
Showing 5 of 67 · See all- K051257Adult Cerebral Oximeter, Model 2040Cas Medical Systems, Inc. · 2005 · cites it directly63descendants
- K073036Fore-Sight, MC-2000 SeriesCas Medical Systems, Inc. · 2008 · cites it directly59descendants
- K061960Fore-Sight Cerebral Oximeter Monitor, Model 2040Cas Medical Systems, Inc. · 2006 · cites it directly59descendants
- K083892Fore-Sight, Model MC-2000 Series (MC-2000, MC-2010, MC2020, MC2030)Cas Medical Systems, Inc. · 2009 · cites it directly58descendants
- K091452Fore-Sight, Model MC-2000 Series (MC 2000, MC2010, MC-2020,MC2030)Cas Medical Systems, Inc. · 2009 · cites it directly57descendants
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −5 | K931154 | Evis 200 System | Olympus Corp. | 1993 | — |
| −4 | K963033 | BF 240/P240/IT240 Bronchovideoscope & Accessories | Olympus America, Inc. | 1996 | 6 |
| −3 | K981543 | Olympus LF-TP and LF-DP Tracheal Intubation Fiberscopes, Accessories and… | The Olympus Optical Co. | 1998 | 5 |
| −2 | K002231 | LF-DP Gastrointestinal and Sigmoid Fiberscope, Accessories and Ancillary… | Olympus Optical Co., Ltd. | 2001 | — |
| −1 | K011869 | Xenf-DP Rhino-Laryngofiberscope, Its Accessories and Ancillary Equipment | The Olympus Optical Co. | 2001 | — |
| 0 (this device) | K040684 | T-Stat Microvascular Tissue Oximeter, Model 303 | Spectros Corporation | 2004 | — |
| +1 | K051257 | Adult Cerebral Oximeter, Model 2040 | Cas Medical Systems, Inc. | 2005 | — |
| +1 | K073036 | Fore-Sight, MC-2000 Series | Cas Medical Systems, Inc. | 2008 | — |
| +1 | K061960 | Fore-Sight Cerebral Oximeter Monitor, Model 2040 | Cas Medical Systems, Inc. | 2006 | — |
| +1 | K083892 | Fore-Sight, Model MC-2000 Series (MC-2000, MC-2010, MC2020, MC2030) | Cas Medical Systems, Inc. | 2009 | — |
| +1 | K091452 | Fore-Sight, Model MC-2000 Series (MC 2000, MC2010, MC-2020,MC2030) | Cas Medical Systems, Inc. | 2009 | — |
Other ancestors by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 1985 | 1 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 1 | 0 |
| 1995 | 1 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 3 | 0 |
| 1999 | 1 | 0 |
| 2000 | 1 | 0 |
| 2002 | 2 | 0 |
Descendants by year cleared
| Year cleared | Devices | With a Class I recall |
|---|---|---|
| 2005 | 1 | 0 |
| 2006 | 1 | 0 |
| 2008 | 3 | 0 |
| 2009 | 2 | 0 |
| 2010 | 3 | 0 |
| 2012 | 3 | 0 |
| 2013 | 1 | 0 |
| 2014 | 2 | 0 |
| 2015 | 3 | 0 |
| 2016 | 2 | 0 |
| 2017 | 1 | 0 |
| 2018 | 1 | 0 |
| 2019 | 5 | 0 |
| 2020 | 3 | 0 |
| 2021 | 7 | 0 |
| 2022 | 6 | 0 |
| 2023 | 8 | 0 |
| 2024 | 6 | 0 |
| 2025 | 6 | 0 |
| 2026 | 3 | 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 MUD? 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 MUD device
- #1 K223651 Cerebral Adaptive Index (CAI) Algorithmscore 19.8 · 29 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (6)
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 |
|---|---|---|---|
| * | K023938 | Modification to Inspectra Tissue Spectrometer System, Model 325Summary page 2…ices Summaries # Predicate Feature Manufacturer Device K-Number 1. Tissue Oximeter Hutchinson InSpectra 325 K023938 2. Tissue Oximeter Somanetics Invos 5100 K001842 3. Relative Hemoglobin Nellcor… | 2002 |
| * | K001842 | Adult/Pediatric Cerebral Oximeter, Model Invos 5100Summary page 2…K-Number 1. Tissue Oximeter Hutchinson InSpectra 325 K023938 2. Tissue Oximeter Somanetics Invos 5100 K001842 3. Relative Hemoglobin Nellcor N-395 K991823 4. Site-Specific: Oral Olympus… | 2000 |
| * | K991823 | N-395 Pulse Oximeter, Model N-395Summary page 2…K023938 2. Tissue Oximeter Somanetics Invos 5100 K001842 3. Relative Hemoglobin Nellcor N-395 K991823 4. Site-Specific: Oral Olympus XENF-DP K011869 5. Site-Specific: Colon Olympus… | 1999 |
| * | K011869 | Xenf-DP Rhino-Laryngofiberscope, Its Accessories and Ancillary EquipmentSummary page 2…K001842 3. Relative Hemoglobin Nellcor N-395 K991823 4. Site-Specific: Oral Olympus XENF-DP K011869 5. Site-Specific: Colon Olympus LF-DP K002231 6. Site-Specific: Endo Olympus… | 2001 |
| * | K002231 | LF-DP Gastrointestinal and Sigmoid Fiberscope, Accessories and Ancillary EquipmentSummary page 2…K991823 4. Site-Specific: Oral Olympus XENF-DP K011869 5. Site-Specific: Colon Olympus LF-DP K002231 6. Site-Specific: Endo Olympus Thoracoscope / K915857… | 2001 |
| * | K915857 | Flexible Tip Thoracoscope/LaparoscopeSummary page 2…K011869 5. Site-Specific: Colon Olympus LF-DP K002231 6. Site-Specific: Endo Olympus Thoracoscope / K915857 Laparoscope IV. General Description The Spectros T-StatTM 303 Tissue… | 1994 |
What descends from it? (67)
See all 677 later devices cite it directly; ranked here by how many devices descend from each in turn.
| Number | Device | Decided | Descendants |
|---|---|---|---|
| K051257 | Adult Cerebral Oximeter, Model 2040 | 2005 | 63 |
| K073036 | Fore-Sight, MC-2000 Series | 2008 | 59 |
| K061960 | Fore-Sight Cerebral Oximeter Monitor, Model 2040 | 2006 | 59 |
| K083892 | Fore-Sight, Model MC-2000 Series (MC-2000, MC-2010, MC2020, MC2030) | 2009 | 58 |
| K091452 | Fore-Sight, Model MC-2000 Series (MC 2000, MC2010, MC-2020,MC2030) | 2009 | 57 |
| K081233 | T-Stat 303 Ischemia Monitoring System | 2008 | 56 |
| K112826 | Noorvms-Oxy Tissue Oxygen and Temperture Monitor | 2012 | 0 |
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 11 years and passes through 5 companies; a new generation was cleared every 2.6 years on median.
- 4 of the 19 ancestors have a recall of any class.
- Of its descendants, K051257 (Cas Medical Systems, Inc., 2005) has gone furthest, with 63 descendants of its own.
- 3 other devices also cite its predicate K023938.
How does its category compare?
All MUD devicesMUD Oximeter, Tissue Saturation: FDA decisions, review times, recalls and adverse event reports over 20 years.
FDA decisions per year · MUD
2in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · MUD
124in 2024
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · MUD
1in 2023
Class I (0 since 2007) Class II/III not classified
Adverse event reports per year · MUD
131in 2025
MAUDE reports naming product code MUD, 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 | 4 | 72 | 0 | 2 |
| 2009 | 4 | 96 | 1 | 7 |
| 2010 | 4 | 59 | 0 | 1 |
| 2011 | 2 | — | 0 | 2 |
| 2012 | 6 | 211 | 0 | 3 |
| 2013 | 2 | — | 0 | 8 |
| 2014 | 5 | 109 | 0 | 4 |
| 2015 | 3 | 107 | 0 | 0 |
| 2016 | 4 | 167 | 0 | 9 |
| 2017 | 3 | 249 | 0 | 24 |
| 2018 | 3 | 128 | 0 | 38 |
| 2019 | 7 | 88 | 0 | 107 |
| 2020 | 2 | — | 0 | 50 |
| 2021 | 2 | — | 0 | 27 |
| 2022 | 2 | — | 2 | 52 |
| 2023 | 2 | — | 1 | 73 |
| 2024 | 5 | 124 | 0 | 140 |
| 2025 | 2 | — | 0 | 131 |
| 2026 | 1 | — | 1 | — |
What is it indicated for?
The Spectros T-StatTM 303 Microvascular Tissue Oximeter is intended for use as an adjunct monitor of the localized hemoglobin oxygen saturation of blood in the microvascular tissue spaces (StO 2%) in infants, children, or adults at risk for reduced-flow and no-flow ischemic states.
The prospective clinical value of measurements made with the TStatTM Oximeter has not been demonstrated in disease states. The T-StatTM Oximeter should not be used as the sole basis for diagnosis or therapy.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K040684 · printed Nov 6, 2026
Cite this page
510(k) Report. “K040684: T-Stat Microvascular Tissue Oximeter, Model 303.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K040684
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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