The MAYFIELD®/ ACCISS™ Image-guided Stereotactic Workstation and the MAYFIELD®/Optical ACCISS™ Image-guided Stereotactic Workstation (OASYS"), are indicated for use in guidance and localization in open craniotomies and in spinal surgeries. The ACCISS™ Systems are indicated for any medical condition in which the use of stereotactic surgery may be considered safe and effective, and where a reference to a rigid anatomical structure, such as a skull, a long bone, or vertebra, can be identified relative to a CT or MR based model of the anatomy.

Device Description

Spine Applications is software that allows the user to select ("crop") images of the portion of the spine under consideration from images of the entire spinal column. Also included is an accessory, the MAYFIELD® ACCISS" Spine Ring" Assembly (hereafter referred to as Spine Ring). The indications for use of the Arm and Optical Systems have been expanded to include use in spinal surgeries.

With Spine Applications, the Arm and Optical Systems can be used to identify spinal anatomical landmarks on the preoperative patient scans and also on the patient's spine to achieve registration with the imaged data set. After the correlation, the indication of the probe orientation appears on the monitor screen and moves through the CT or MRI data in correct relation to the probe as manipulated by the surgeon. This is the same process as that used in cranial surgery with the Systems.

Spine Applications, in conjunction with the Arm and Optical Systems, is a computer-based system designed for use in the surgical theatre. The Arm System uses a position-sensing articulated Arm with a probe that acts as a localizing device. The Optical System uses a Sensor Assembly positioned above/beside the surgical site that tracks the position and orientation of digitizing probes and other instruments.

To use either System, the computer is loaded with the patient's computed tomography (CT) or magnetic resonance image (MRI) data and these images are correlated to the patient by physically matching points of anatomical landmarks. The System computer interfaces with CT or MR images and provides probe orientation/ probe-tip position. The indication of the probe orientation and probe-tip position appears on the monitor screen and moves through the CT or MRI data in correct relation to the probe as manipulated by the surgeon.

AI/ML Overview

Here's an analysis of the provided text to extract the requested information regarding acceptance criteria and the study proving device performance:

1. Table of Acceptance Criteria and Reported Device Performance:

The document primarily focuses on establishing substantial equivalence to predicate devices for a software module (Spine Applications) and an accessory (Spine Ring) that expand the indications for use of existing image-guided stereotactic workstations to include spinal surgery. It does not define explicit, quantitative acceptance criteria or report specific performance metrics for the device against such criteria.

Instead, the performance section states:

"The Spine Applications performed to the surgeons' satisfaction with regard to preoperative planning and accuracy."
"The clinical data for Spine Applications compared favorably with the data for cranial surgery performed using the Systems."

This indicates a qualitative assessment of surgeon satisfaction and a comparative assessment with existing cranial surgery data (which itself is not detailed here for performance metrics).

Therefore, a table of explicit acceptance criteria and corresponding numerical performance cannot be constructed from the provided text.

2. Sample Size Used for the Test Set and Data Provenance:

Sample Size: Not explicitly stated. The text mentions "The Arm System and the Optical System, both with Spine Applications, were used by surgeons under authority of the Institutional Review Boards for the hospitals involved." This implies clinical use, but the number of cases or patients is not specified.
Data Provenance: The study was conducted under the authority of Institutional Review Boards (IRBs) for "the hospitals involved," indicating a clinical setting. It is implied to be a prospective use study given it was done by surgeons with the new applications. The country of origin is not specified but is likely the USA given the FDA 510(k) context.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:

Number of Experts: Not specified.
Qualifications of Experts: The text states the systems "were used by surgeons," implying that these surgeons acted as the experts in evaluating the device's performance. Their specific qualifications (e.g., years of experience, subspecialty) are not detailed.

4. Adjudication Method for the Test Set:

The text does not describe any formal adjudication method (e.g., 2+1, 3+1). The evaluation appears to be based on the "satisfaction" of the surgeons using the device.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve with AI vs. Without AI Assistance:

No MRMC comparative effectiveness study is described where human readers' performance with and without AI assistance is compared, nor is an "effect size" mentioned. The study focused on surgeon satisfaction and comparison to cranial surgery data rather than measuring improvement of human readers with AI assistance.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:

This device is an image-guided surgery system where a human surgeon is inherently "in-the-loop." The software (Spine Applications) provides guidance to the surgeon. Therefore, a standalone (algorithm-only) performance study, in the typical sense of evaluating diagnostic AI, would not be applicable or described for this type of device. The evaluation is on the system's utility and accuracy when used by a surgeon.

7. The Type of Ground Truth Used (Expert Consensus, Pathology, Outcomes Data, etc.):

The "ground truth" implicitly used for evaluation was the surgeons' assessment of the "satisfaction with regard to preoperative planning and accuracy" during actual surgical procedures. This can be interpreted as a form of expert assessment/clinical utility in a real-world surgical context, rather than a quantifiable, independent ground truth like pathology or long-term outcomes data.

8. The Sample Size for the Training Set:

The document does not describe the development or training of new algorithms (AI in the modern sense) with a training set. Instead, it states that "Spine Applications provides the surgeon with image-guided technology, using the identical algorithms currently used for cranial image-guidance." This implies that existing, validated algorithms (presumably for cranial surgery) are being reused or adapted for spinal applications. Therefore, no separate "training set" for new spine-specific algorithms is mentioned.

9. How the Ground Truth for the Training Set Was Established:

As no new training set or algorithms are described for Spine Applications, the establishment of ground truth for a training set is not applicable or detailed in this document. The existing algorithms from the predicate cranial devices would have had their own validation and associated ground truth established during their original development, which is outside the scope of this 510(k) summary.

Summary

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JUL 12 1999

II 510(k) SUMMARY AND CERTIFICATION

K 99/267

Summary of Safety and Effectiveness

Spine Applications for the MAYFIELD®/ ACCISS™ Operating Arm and Optical ACCISS™ Systems

Pursuant to Section 513(i) of the Federal Food, Drug and Cosmetics Act, as amended by the Safe Medical Devices Act [SMDA] of 1990.

Summary Preparation Date: April 9, 1999.

General Information:Classification Name:	Stereotactic Instrumentation
Common/Usual Name:	Computer-Based Image-guided Stereotactic SurgeryPlanning System - Spine Applications
Proprietary Name:	Spine Applications for the MAYFIELD®/ ACCISS™Operating Arm and Optical ACCISS™ Systems.

Applicant's Name and Address:

Kenneth B. Miller, Regulatory Affairs and Quality Assurance Director Ohio Medical Instrument Company, Inc. 4900 Charlemar Drive Cincinnati, Ohio 45227

2. Name of predicate device(s):

MAYFIELD®/ ACCISS" Image-guided Stereotactic Workstation (K955397), MAYFIELD®/Optical ACCISS™ Image-guided Stereotactic Workstation [OASYS"] (K982244), BUDDE® Halo Retractor System [K830332]

3. Classification:

Neurosurgical stereotactic instruments and accessories are Class II (21CFR 882.4800 and 882.4560).

4. Performance Standards:

No applicable performance standards have been established by FDA under section 514 of the Food, Drug and Cosmetic Act.

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II 510(k) SUMMARY AND CERTIFICATION (continued)

5. Intended Use and Device Description:

Intended Use: The intended use of the MAYFIELD®/ ACCISS™ Image-guided Stereotactic Workstation [K955397] (hereafter referred to as the Arm System), and the MAYFIELD® (Optical ACCISS™ Image-guided Stereotactic Workstation (K982244) (hereafter referred to as the Optical System) is unchanged by Spine Applications for the MAYFIELD® ACCISS" Operating Arm and Optical ACCISS " Systems Module [4-12-A-1137] (hereafter referred to as Spine Applications). However, the Systems' indications for use have been expanded to include spinal surgery procedures.

The Arm and Optical Systems are intended for use as devices that use diagnostic images of the patient, acquired specifically to assist the surgeon with presurgical planning, to provide orientation and reference information during intra-operative procedures.

The MAYFIELD® ACCISS Image-guided Stereotactic Workstation and the MAYFIELD® Optical ACCISS™ Image-guided Stereotactic Workstation (OASYS") are indicated for use in guidance and localization in open craniotomies and in spinal surgeries. The ACCISS™ Systems are indicated for any medical condition in which the use of stereotactic surgery may be considered safe and effective, and where a reference to a rigid anatomical structure, such as a skull, a long bone, or vertebra, can be identified relative to a CT or MR based model of the anatomy.

Device Description: Spine Applications is software that allows the user to select ("crop") images of the portion of the spine under consideration from images of the entire spinal column. Also included is an accessory, the MAYFIELD® ACCISS" Spine Ring" Assembly (hereafter referred to as Spine Ring). The indications for use of the Arm and Optical Systems have been expanded to include use in spinal surgeries.

With all image-guided surgery systems there must be a fixed positional relationship or link between the patient and the system. For cranial surgery, this link to the patient is achieved through the use of the Halo that is attached to the MAYFIELD® Skull Clamp A2000 [K932807] (hereafter referred to as the Skull Clamp). The Arm or the DRF is attached to the Halo, thereby achieving a firm and rigid relationship to the patient.

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II 510(k) SUMMARY AND CERTIFICATION (continued)

5. Intended Use and Device Description: (continued)

For spinal procedures and use of Spine Applications, a similar "ring", the Spine Ring, may be used, if the surgeon elects. The Spine Ring is actually a segment of the Halo that can be connected to any standard spine retractor system. Attachment of the Spine Ring to the retractor that is attached to the patient achieves the same firm and rigid relationship to the patient as that of the Halo. The Spine Ring is sterilized via steam sterilization methods just as the Halo.

Spine Applications, in conjunction with the Arm and Optical Systems, is a computerbased system designed for use in the surgical theatre. The Arm System uses a position-sensing articulated Arm with a probe that acts as a localizing device. The Optical System uses a Sensor Assembly positioned above/beside the surgical site that tracks the position and orientation of digitizing probes and other instruments.

The Arm System and the Optical System, in conjunction with Spine Applications (the underlined items], consists of the following items:

A. Workstation

B. Software
- · Includes MAYFIELD® ACCISS Spine Applications Module [4-12-A-1137]
C. Probe Assembly [articulated arm or optical tracking system] · Includes MAYFIELD® ACCISS" Spine Ring" Assembly [4-12-C-1123]
D. Optical Tracking Accessories
E. Training Accessories
F. Supported Modalities
- CT
- MRI

G. Options:

Tektronix Phaser II SDX Color Printer Overland Data 5612 9-Track Tape Drive

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II 510(k) SUMMARY AND CERTIFICATION (continued)

6. Summary of Substantial Equivalence:

Spine Applications is substantially equivalent to the following devices:

· The MAYFIELD® ACCISS™ Image-guided Stereotactic Workstation [K955397],
· The MAYFIELD®Optical ACCISS™ Image-guided Stereotactic Workstation (OASYS") [K982244].
· The BUDDE® Halo Retractor System [K830332]

Indications:

· The Arm System and the Optical System, in conjunction with Spine Applications, are used in the identical manner as the predicate devices. Both Systems are used for localization as well as correlation of preoperative CT or MRI data with patient anatomy to assist in planning and/or performance of surgery. Spine Applications provides the surgeon with image-guided technology, using the identical algorithms currently used for cranial image-quidance, plus the ability to select or "crop" the images of the specific vertebral bodies involved.
· The Spine Ring is used in an identical manner as the predicate device to provide a rigid base for the Arm System or Optical System components and accessories.

Design:

· The Arm System, in conjunction with Spine Applications, utilizes a mechanical articulated Arm that acts as a 3-0 digitizer, which interfaces to a computer graphics workstation that displays reformatted CT or MR images in a variety of configurations. The Optical System, in conjunction with Spine Applications, utilizes a 3-camera Sensor Assembly, a DRF with 3 LEDs, and a probe handle with 3 LEDs that acts as a 3-D digitizer. The Sensor Assembly interfaces to a computer graphics workstation ' that displays reformatted CT or MR images in a variety of configurations. Both Systems utilize the identical equipment and algorithms for image-guided cranial surgery planning and for image-quided spinal surgery planning. The spinal surgery planning algorithms of both Systems include the module for spinal vertebral body selection {"cropping"}.

Materials:

· Materials used to manufacture Spine Applications and the Spine Ring are the same as those used for the predicate devices with the exceptions noted in Design, above.

Manufacturing:

· Manufacturing processes for Spine Applications and the Spine Ring are the same as those used for the predicate devices. with exceptions noted in Design, above.

Specifications:

· Specifications of Spine Applications and the Spine Ring are the same as those of the predicate devices, with the exceptions noted in Design, above.

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11 510(k) SUMMARY AND CERTIFICATION (continued)

6. Summary of Substantial Equivalence: (continued)

Performance:

· The Arm System and the Optical System, both with Spine Applications, were used by surgeons under authority of the Institutional Review Boards for the hospitals involved. The Spine Applications performed to the surgeons' satisfaction with regard to preoperative planning and accuracy. The clinical data for Spine Applications compared favorably with the data for cranial surgery performed using the Systems.

7. Packaging:

The Arm and Optical Systems, Spine Applications, and the Spine Ring are supplied in industry standard medical-grade packaging suitable for electronic equipment and surgical instruments. The shippers and cartons are of suitable design to ensure product identification and protection from damage during shipping and storage.

8. Sterilization:

The Arm and Optical Systems, Spine Applications, and the Spine Ring are supplied NON-STERILE. These non-sterile devices are packaged in "clean" condition, and must be removed from their shipping and packing materials, then appropriately cleaned before use as described in the instruction manuals.

A sterilization process, following AAMI TIR No. 12-1994, has been validated for the Spine Ring and the Halo. The validated sterilization cycle for the Halo and the Spine Ring is:

· Steam sterilization at 132 degrees C, under high vacuum [2.0 psia] for 3 minutes [STS Test No.: 98-3359, STS Study No. GMP-1998-0082, on file at OMI].
The Instruction Manuals for Spine Applications, the Optical System, and the Arm System provide instructions on sterile use and reprocessing of components that require sterilization by the user.

9. Conclusion:

The Intended Use, Indications for Use, Design, Materials, Manufacturing, Specifications, Performance, Packaging and Sterilization of Spine Applications and the Spine Ring do not raise any new unresolved issues relating to safety and effectiveness. Ohio Medical Instrument Company, Inc. therefore considers Spine Applications and the Spine Ring as substantially equivalent to the predicate devices.

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11 510(k) SUMMARY AND CERTIFICATION (continued)

10. Comparison Table:

FEATURE	MAYFIELD ®/ ACCISS™ Operating Armand Optical ACCISS™ Systems[K955397, K982244]	Spine Applications for theMAYFIELD ®/ ACCISS™ Operating Armand Optical ACCISS™ Systems
Intended Use	The Arm System and the Optical Systemare intended for use as devices that, bythe use of diagnostic images of thepatient, acquired specifically to assist thesurgeon with presurgical planning.provide orientation and referenceinformation during intra-operativeprocedures.	• Same.
Indications forUse	The Arm System and the Optical Systemare indicated for:	The Arm System and Optical System,with Spine Applications, are indicated for:
	• Guidance and localization in opencraniotomies, and for surgeries that aretraditionally performed with astereotactic apparatus, such asbiopsies, thalamotomies, and electrodeimplants. The Systems may also beused to review medical images in aneurosurgical context.	• Use in guidance and localization inopen craniotomies and in spinalsurgeries. The ACCISS Systems areindicated for any medical condition inwhich the use of stereotactic surgerymay be considered safe and effective,and where a reference to a rigidanatomical structure, such as a skull, along bone, or vertebra, can beidentified relative to a CT or MR basedmodel of the anatomy.
Design	• Arm or Optical tracking for3-D digitizing.	• Same.
	• Interfaces to computer graphicsworkstation.	• Same.
	• Displays reformatted CT or MR imagesin variety of configurations.	• Same.
	• Algorithms for image-guided surgeryplanning.	• Same.
	• Software to show body part undergoingsurgery - head.	• Same.
		• Software to show body part undergoingsurgery - spine.

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III 510(k) SUMMARY AND CERTIFICATION (continued)

10. Comparison Table: (continued)

FEATURE	MAYFIELD®/ ACCISS" Operating Armand Optical ACCISS" Systems[K955397, K982244]	Spine Applications for theMAYFIELD®/ ACCISS™ Operating Armand Optical ACCISS" Systems
Type of Detector	• Optically encoded signals from joints ofarticulated arm.	• Same.
	• A 3-camera Sensor Assembly detectsinfrared signals emitted from LEDs onhand-held probe handle. The SensorAssembly is mounted on a dedicated,mobile stand.	• Same.
RegistrationTechnique	• Scanned Fiducials	• Same.
	• Anatomical Fiducials	• Same.
OperatingSoftware	• Anatomical Fiducials• Structure: MS-DOS, with two majorfunctions: Image Importation, andSurgical Applications [navigation].Uses a Graphical User Interface tofacilitate interaction with user.	• Same. Modified Graphical UserInterface with similar functionality.
	• Image Manipulation: Unreformatted,reformatted, 3-D surface rendering.	• Same.
Materials	• Aluminum 6061 [anodized] for trackingprobe [K853627 for use of anodizedaluminum].	• Same
	• Stainless steel ASTM F899, passivatedQQ-P-35 Type 2 for sterile probe-tips.	• Same
Accessories	• BUDDE® Halo Retractor System[K830332]	• Same.• MAYFIELD®/ ACCISS™ Spine Ring™Assembly [4-12-C-1123]

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Image /page/7/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a circular seal with the words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter. Inside the circle is a stylized image of an eagle with three lines representing its wings.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JUL 12 1999

Mr. Kenneth B. Miller Director, Regulatory Affairs and Quality Assurance Ohio Medical Instrument Co., Inc. 4900 Charlemar Drive Cincinnati, Ohio 45227

K991267 Re:
Trade Name: MA YFIELD® ACCISS™ Operating Arm and Optical ACCISS™ Systems Regulatory Class: II Product Code: HAW Dated: April 9, 1999 Received: April 13, 1999

Dear Mr. Miller:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirement, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

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Page 2 – Mr. Kenneth B. Miller

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address "http://www.fda.gov/cdrh/dsmamain.html".

Sincerely yours,

Celia M. Witten, Ph.D., M.D. Director Division of General and Restorative Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Page 1 of ﻠﺴ

510(k) Number (if known):

K991267

Device Name: Spine Applications for the MAYFIELD®/ACCISS™ Operating Arm and Optical ACCISS™ Systems

Indications For Use:

The MAYFIELD®/ ACCISS™ Image-guided Stereotactic Workstation and the MAYFIELD®/Optical ACCISS™ Image-guided Stereotactic Workstation (OASYS"), are indicated for use in guidance and localization in open craniotomies and in spinal indicated for use in galadino and indicated for any medical condition in which the use of stereotactic surgery may be considered to be safe and effective, and where a reference to a rigid anatomical structure, such as a skull, a long bone, or vertebra, can be identified relative to a CT or MR based model of the anatomy.

(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

(Division Sign-Off)
Division of General Restorative Devices K991267
510(k) Number

Prescription Use X
(Per 21 CFR 801.109)
OR
Over-The-Counter Use

(Optional Format - 1 - 2 - 96)

Page A-7

Regulation Number and Section

§ 882.4560 Stereotaxic instrument.

(a)
Identification. A stereotaxic instrument is a device consisting of a rigid frame with a calibrated guide mechanism for precisely positioning probes or other devices within a patient's brain, spinal cord, or other part of the nervous system.(b)
Classification. Class II (performance standards).