510(k) Report

510(k) · Cleared

Cleared

Mayfield-Acciss Workstation

K955397510(k) TraditionalCleared Apr 30, 1996158-day reviewClass II21 CFR 882.4560

Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly, last Nov 3, 2026

Nomos Corp. · HAW Neurological Stereotaxic Instrument

Cleared on Apr 30, 1996 as substantially equivalent to K911783 (I.S.G. Technologies, Inc., 1994) and 2 other predicates after a 158-day review. Its family tree reaches back 1 generation to 1985. 15 later devices descend from it.

Decided
Apr 30, 1996
Review
158 days
Class
Class II
Product code
HAW
Recalls
None
Predicates
3

Its longest line of descent runs back 1 generation to K851659 (1985). 3 ancestors in all. 15 later devices descend from it, 5 citing it directly.

Other ancestors, by year clearedDescendants, by year cleared 1994: 1 other ancestor1992: 1 other ancestor1999: 3 descendants cleared1998: 2 descendants cleared2005: 2 descendants cleared2003: 1 descendant cleared2004: 1 descendant cleared2012: 2 descendants cleared2008: 1 descendant cleared2013: 1 descendant cleared2014: 2 descendants clearedReference device: K862971 · Micra Microsurgical Instruments · Cordis Corp. · 1986K851659 · Skull Mounted Stereotactic Surgical Device · Medco Products, Co., Inc. · 19851990200020102020
Other ancestors, by generationDescendants, by generation 1 generation back: 2 other ancestors 1 generation forward: 5 descendants2 generations forward: 4 descendants3 generations forward: 4 descendants4 generations forward: 1 descendant5 generations forward: 1 descendant K851659 · Skull Mounted Stereotactic Surgical Device · Medco Products, Co., Inc. · 19850+5
  1. Root · 1 generation backK851659 Skull Mounted Stereotactic Surgical DeviceMedco Products, Co., Inc. · 1985
  2. This deviceK955397 Mayfield-Acciss WorkstationNomos Corp. · 1996
  3. Descendant · cites it directly · 10 of its ownK981424 Nomos Bat Ultrasound Localization and Positioning SystemNomos Corp. · 1998
  4. Descendant · 2 generations on · 4 of its ownK032100 I-BEAMComputerized Medical Systems, Inc. · 2003
  5. Descendant · 2 generations on · 3 of its ownK042110 BeamcathBeampoint AB · 2005
  6. Descendant · 2 generations on · 3 of its ownK041937 RestituResonant Medical, Inc. · 2004
  7. Descendant · 3 generations on · 2 of its ownK111332 Clarity Obp SystemElekta, Ltd. · 2012

Showing 5 of 15 descendants. See all descendants

Descendants cleared per year

1998: 21999: 32003: 12004: 12005: 22008: 12012: 22013: 12014: 2
1998high 3 (1999) · low 0 (2000)2026

Most influential descendants

Showing 5 of 15 · See all
  • K981424Nomos Bat Ultrasound Localization and Positioning SystemNomos Corp. · 1998 · cites it directly10descendants
  • K032100I-BEAMComputerized Medical Systems, Inc. · 2003 · 2 generations on4descendants
  • K042110BeamcathBeampoint AB · 2005 · 2 generations on3descendants
  • K041937RestituResonant Medical, Inc. · 2004 · 2 generations on3descendants
  • K111332Clarity Obp SystemElekta, Ltd. · 2012 · 3 generations on2descendants
View FIG. 1 as a table

Line of descent and top descendants

GenerationNumberDeviceApplicantDecidedRecalls
−1K851659Skull Mounted Stereotactic Surgical DeviceMedco Products, Co., Inc.1985—
0 (this device)K955397Mayfield-Acciss WorkstationNomos Corp.1996—
+1K981424Nomos Bat Ultrasound Localization and Positioning SystemNomos Corp.1998—
+2K032100I-BEAMComputerized Medical Systems, Inc.2003—
+2K042110BeamcathBeampoint AB2005—
+2K041937RestituResonant Medical, Inc.2004—
+3K111332Clarity Obp SystemElekta, Ltd.2012—

Other ancestors by year cleared

Year clearedDevicesWith a Class I recall
199210
199410

Descendants by year cleared

Year clearedDevicesWith a Class I recall
199820
199930
200310
200410
200520
200810
201220
201310
201420
FIG. 1 — Lineage of K955397, 1985–2014Source: FDA 510(k) summaries, read by 510(k) Report · How lineage is built

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Notable FDA decisions, review times and new Class I recalls. See an issue.

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 HAW? 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 HAW device

  1. #1 K253856 Geniant Cranial (Navigated Neurosurgical…score 15.0 · 11 generations · no Class I recall
  2. #2 Held for the reportin the report
  3. #3 Held for the reportin the report
Get a 510(k) Report

What was it cleared against? (3)

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.

TypeNumberDeviceApplicantDecidedRecalls
*K911783Allegro Viewing Wand
Summary page 1
…ident, Administration and Regulatory Affairs NOMOS Corporation 2591 Wexford Bayne Road Sewickley, PA 15143 ll. Name of predicate device(s): ISG Allegro Viewing Wand (K911783) Pelorus Arc Carrier (K851659A) CORITechs CORITaxic I Workstation (K915791) Cordis Micra Microosurgical Instruments (K862971) -…
I.S.G. Technologies, Inc.1994—
*K851659Skull Mounted Stereotactic Surgical Device
Summary page 1
…latory Affairs NOMOS Corporation 2591 Wexford Bayne Road Sewickley, PA 15143 ll. Name of predicate device(s): ISG Allegro Viewing Wand (K911783) Pelorus Arc Carrier (K851659A) CORITechs CORITaxic I Workstation (K915791) Cordis Micra Microosurgical Instruments (K862971) - for use of Titanium in contact…
Medco Products, Co., Inc.1985—
*K915791Coritaxic Multi-Modal Stereotaxi Workstation
Summary page 1
…d Bayne Road Sewickley, PA 15143 ll. Name of predicate device(s): ISG Allegro Viewing Wand (K911783) Pelorus Arc Carrier (K851659A) CORITechs CORITaxic I Workstation (K915791) Cordis Micra Microosurgical Instruments (K862971) - for use of Titanium in contact with Brain Tissue l1l. Classification: Neu…
Coritechs, Inc.1992—
†K862971Micra Microsurgical InstrumentsCordis Corp.1986—

Also cleared against K911783: 7 other devices →

What descends from it? (15)

See all 15

5 later devices cite it directly; ranked here by how many devices descend from each in turn.

NumberDeviceApplicantDecidedDescendants
K981424Nomos Bat Ultrasound Localization and Positioning SystemNomos Corp.199810
K982244Mayfield Acciss Optical SystemOhio Medical Instrument Co., Inc.19982
K992843The Mayfield / Acciss System with Windows NT for Cranial Surgery, the Mayfield / Optical…Ohio Medical Instrument Co., Inc.19990
K991636Elekta Stereotactic GuideElekta Instrument AB19990
K991267Spine Applications for the Mayfield/Acciss Operating Arm and Optical Acciss Systems…Ohio Medical Instrument Co., Inc.19990

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?

  • None of the 3 ancestors has a recall.
  • Of its descendants, K981424 (Nomos Corp., 1998) has gone furthest, with 10 descendants of its own.
  • 7 other devices also cite its predicate K911783.

How does its category compare?

All HAW devices

HAW Neurological Stereotaxic Instrument: FDA decisions, review times, recalls and adverse event reports over 20 years.

FDA decisions per year · HAW

9in 2025

2007: 152008: 122009: 82010: 62011: 42012: 82013: 32014: 52015: 102016: 92017: 72018: 62019: 102020: 52021: 92022: 72023: 142024: 72025: 92026 (partial year): 5
2007high 15 (2007) · low 3 (2013)2026

2026 to Oct 25, outlined.

Median 510(k) review, days · HAW

163in 2025

2007: 107 days median2008: 112 days median2009: 221 days median2010: 138 days median2011: 66 days median2012: 178 days median2013: 172 days median2014: 238 days median2015: 232 days median2016: 175 days median2017: 226 days median2018: 112 days median2019: 147 days median2020: 88 days median2021: 168 days median2022: 128 days median2023: 142 days median2024: 107 days median2025: 163 days median2026 (partial year): 162 days median
2007high 238 (2014) · low 66 (2011)2026

Receipt to decision; years with fewer than 3 clearances left blank.

Recalls per year · HAW

2in 2025

2007: 22008: 102009: 62010: 282011: 52012: 42013: 6, 1 Class I2014: 52015: 32016: 52017: 22018: 2, 2 Class I2019: 4, 1 Class I2020: 12021: 4, 2 Class I2022: 12023: 4, 1 Class I2024: 2, 2 Class I2025: 22026 (partial year): 6
2007high 28 (2010) · low 1 (2020)2026

Class I (9 since 2007) Class II/III not classified

Adverse event reports per year · HAW

3,425in 2025

2007: 492008: 532009: 962010: 2992011: 1,7252012: 9862013: 1,2902014: 1,6062015: 1,7672016: 1,8282017: 3,5052018: 4,4392019: 6,0622020: 3,4802021: 2,8272022: 1,9292023: 2,5102024: 3,7552025: 3,425
2007high 6,062 (2019) · low 49 (2007)2025

MAUDE reports naming product code HAW, not matched to any one device; reports are not rates.

View these four charts as a table
YearDecisionsMedian 510(k) review, daysRecalls (Class I)MAUDE reports
200715107249
2008121121053
20098221696
2010613828299
201146651,725
201281784986
201331726 (1)1,290
2014523851,606
20151023231,767
2016917551,828
2017722623,505
201861122 (2)4,439
2019101474 (1)6,062
202058813,480
202191684 (2)2,827
2022712811,929
2023141424 (1)2,510
202471072 (2)3,755
2025916323,425
202651626—

What is it indicated for?

ACCISS is to be used both for guidance and localization in open craniotomies and for surgeries which are traditionally performed with a stereotactic apparatus, such as biopsies, thalamotomies and electrode implants. The system may also be used to review medical images in a neurosurgical context.

Indications for use read by OCR from a scanned FDA summary, so letters may be misread. Check the PDF before quoting it.

Also cleared against K911783

7 other devices cite the same predicate.

  • K983529Instatrak 3000Visualization Technology, Inc. · 19981 Class I recall
  • K982994Skull Base Instatrak SystemVisualization Technology, Inc. · 19981 Class I recall
  • K981998Pediatric Instatrak SystemVisualization Technology, Inc. · 19981 Class I recall
  • K961834Philips Easyguide NeuroPhilips Medical Systems, Inc. · 1996
  • K961844Operating Arm System (Oas) [with CT and MR Images]Radionics Software Applications, Inc. · 1996
  • K960714Isg Viewing WandI.S.G. Technologies, Inc. · 1996

More from Nomos Corp.

21 FDA decisions under this applicant name. See the company

  • K070611Bat Ultrasound Localization and Positioning System, Version 6Nomos Corp. · 2007
  • K060895Nomosstat, Version 1.0Nomos Corp. · 2006
  • K042875NavigatorNomos Corp. · 2005
  • K032209Nomos Corvus 5.0MNomos Corp. · 2003
  • K013036Nomos Motorized Crane IINomos Corp. · 2001

Recent decisions in HAW

The HAW category page

  • K262214Disposable Reflective Marker Spheres (AM-BK115S, AM-BL130S)Guangzhou Aimooe Technology Co., Ltd. · 2026
  • K253856Geniant Cranial (Navigated Neurosurgical Positioning Robot)Koh Young Technology, Inc. · 2026
  • K261932Leksell® Vantage Stereotactic SystemElekta Solutions AB · 2026
  • K253663Zeta Navigation SystemZeta Surgical, Inc. · 2026
  • K253379Stealth AXiS Cranial clinical applicationMedtronic Navigation, Inc. · 2026

https://510kreport.com/device/K955397 · printed Nov 4, 2026

Cite this page

510(k) Report. “K955397: Mayfield-Acciss Workstation.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 4, 2026. https://510kreport.com/device/K955397

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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