The AnatoMark Noninvasive Head Reference System is an accessory for routine head MR that is designed to provide reproducible anatomical markers. The Head Reference System is designed to aid in patient positioning to achieve consistent anatomical images over multiple imaging sessions. The head localizer produces a set of six fiduciary marks on axial images that are positioned reproducibly with reference to stable anatomical structures internal to the patient's cranium. The fiduciary marks are also visible in CT images, making possible the co-registration of CT and MR images.

Device Description

The AnatoMark Noninvasive Head Reference System is a simple device, worn externally on the head, designed for use in routine head or brain MRI to provide reference markers that are visible on magnetic resonance (MR) images. The AnatoMark Noninvasive Head Reference System is intended to provide fiduciary marks that are visible on magnetic resonance (MR) images. The device may also be used to provide MRI/CT co-registration of fiduciary marks. The device is worn externally on the head, is simple and non-invasive, and wearing it is somewhat similar to the wearing of eyeglasses. The device is intended to be used with the "scout" or localization image sequence to establish a reproducible reference plane within the MR system's imaging coordinate system for the subsequent imaging session. At each of three reference locations on the device there is a reference block that contains two reference tubes that appear on MR images. The reference marks are physically implemented as cylinders set in the reference block such that they are orthogonal to each other and cross at their midpoints. When imaged slightly out of plane of the midpoints, the cross-sections of the small cylinders appear as two fiduciary marks that are not side by side. When imaged in the plane of the midpoints, however, the fiduciary marks are side by side. By adjusting the plane of the images such that all three pairs of reference marks show side by side, a reproducible reference plane may be established.

AI/ML Overview

The provided document is a 510(k) summary for the AnatoMark™ Noninvasive Head Reference System, seeking Substantial Equivalence to predicate devices. It describes the device's function and intended use but does not provide detailed acceptance criteria or a study report with specific performance metrics and statistical analyses. The submission focuses on demonstrating substantial equivalence rather than proving device performance against pre-defined acceptance criteria in a quantitative manner.

Therefore, much of the requested information cannot be extracted directly from this document. However, based on the provided text, here's what can be inferred or explicitly stated:

AnatoMark™ Noninvasive Head Reference System Study Information

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria	Reported Device Performance
Explicit acceptance criteria are not mentioned in the document. The submission focuses on demonstrating "reproducible reference markers" and "accuracy substantially equivalent to the accuracy of the predicate device."	"Interneuron Pharmaceuticals has carried out testing of the device to demonstrate that it provides reproducible reference markers." "This testing indicated that the accuracy is substantially equivalent to the accuracy of the predicate device."

2. Sample size used for the test set and the data provenance

Test Set Sample Size: Not specified.
Data Provenance: Not specified (e.g., country of origin, retrospective or prospective).

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

Not applicable/Not specified. The nature of the device (a physical marker system) would likely involve physical measurements of marker reproducibility rather than expert ground truth establishment for a diagnostic output.

4. Adjudication method for the test set

Not applicable/Not specified.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

Not applicable. This device is a passive reference system, not an AI-powered diagnostic tool, so an MRMC study comparing human readers with and without AI assistance is not relevant.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not applicable. This is a physical device, not an algorithm. The testing would have focused on the physical accuracy and reproducibility of the markers themselves.

7. The type of ground truth used

The concept of "ground truth" as typically applied to diagnostic algorithms (e.g., pathology, outcomes data) is not directly applicable here. The "ground truth" in this context would likely be physical measurements of the position and reproducibility of the fiduciary marks relative to a known reference or across multiple imaging sessions.

8. The sample size for the training set

Not applicable. This device does not involve a "training set" in the context of machine learning.

9. How the ground truth for the training set was established

Not applicable.

Summary of Device Performance Claim:

The document states: "Interneuron Pharmaceuticals has carried out testing of the device to demonstrate that it provides reproducible reference markers. This testing indicated that the accuracy is substantially equivalent to the accuracy of the predicate device."

This claim of "substantial equivalence" is the central finding presented in the 510(k) summary, rather than a detailed report of reaching specific, quantitative acceptance criteria for the new device's performance. The "study" mentioned refers to this internal testing to support the substantial equivalence claim.

Summary

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AnatoMark™ Noninvasive Head Reference System

Common/ClassificationName: Accessory to MR Imaging System, 21 CFR 892.1000

Interneuron Pharmaceuticals, Inc. 99 Havden Avenue, Suite 200 Lexington, MA 02173

Telephone: 781-861-8444 FAX: 781-863-2564

Contact: Sonja Loar, Pharm.D., Prepared: April 8, 1998

LEGALLY MARKETED PREDICATE DEVICES A.

The AnatoMark Noninvasive Head Reference System is an accessory to MR devices (21 CFR 892.1000). It shares some features with the Laitinen Stereoadapter 5000 (K881131), cleared as a stereotaxic instrument (21 CFR 882.4560), and the Codman Fiducial Marker System (K953568), cleared as a radiographic film marker (21 CFR 892.1640).

DEVICE DESCRIPTION 8.

**** The AnatoMark Noninvasive Head Reference System is intended to provide fiduciary marks that are visible on magnetic resonance (MR) images. The device may also be used to provide MRI/CT co-registration of fiduciary marks. The device is worn externally on the head, is simple and non-invasive, and wearing it is somewhat similar to the wearing of eveglasses.

The device is intended to be used with the "scout" or localization image sequence to establish a reproducible reference plane within the MR system's imaging coordinate system for the subsequent imaging session. At each of three reference locations on the device there is a reference block that contains two reference tubes that appear on MR images. The reference marks are physically implemented as cylinders set in the reference block such that they are orthogonal to each other and cross at their midpoints. When imaged slightly out of plane of the midpoints, the cross-sections of the small cylinders appear as two fiduciary marks that are not side by side. When imaged in the plane of the midpoints,

AnatoMark Noninvasive Head Reference System - summary

000 034

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however, the fiduciary marks are side by side. By adjusting the plane of the images such that all three pairs of reference marks show side by side, a reproducible reference plane may be established.

C. INTENDED USE

D. SUBSTANTIAL EQUIVALENCE SUMMARY

The AnatoMark Noninvasive Head Reference System does not have the identical indications for use as the predicate devices, but it has the same intended use. The AnatoMark Noninvasive Head Reference System has the same technological characteristics as the predicate devices.

The descriptive characteristics may not be precise enough to assure equivalence, so Interneuron Pharmaceuticals has carried out performance testing to assure equivalence. The resulting performance data do, in fact, demonstrate equivalence. The flowchart for the substantial equivalence algorithm leads to a substantial equivalence decision.

ய் TECHNOLOGICAL CHARACTERISTICS

The AnatoMark Noninvasive Head Reference System has the "same ﺴﺘﺨﺪﻣﺎ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍﻟﻤﺴﺘﺨﺪﻣﺎﺕ ﺍ technological characteristics" as the Laitinen Stereoadapter 5000. Both provide reference markers that are made of materials that can be easily visualized on MR images.
AnatoMark Noninvasive Head Reference System - summary

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F. TESTING

Interneuron Pharmaceuticals has carried out testing of the device to demonstrate that it provides reproducible reference markers. This testing indicated that the accuracy is substantially equivalent to the accuracy of the predicate device.

CONCLUSIONS G.

This 510(k) has demonstrated that the AnatoMark Noninvasive Head Reference System is substantially equivalent to presently marketed devices.

AnatoMark Noninvasive Head Reference System - summary

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Image /page/3/Picture/0 description: The image is a black and white logo for the U.S. Department of Health & Human Services. The logo features a stylized image of an eagle with three heads, representing the department's mission to protect the health of all Americans and provide essential human services. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES • USA" are arranged in a circular pattern around the eagle.

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

JUN

V.P. Regulatory & Scientific Affairs Interneuron Pharmaceuticals, Inc.

99 Hayden Avenue, Suite 200 Lexington, MA 02173

Re:

K981398 Head Reference System (MRI/CT Anatomical Marker) Dated: April 15, 1998 Received: April 17, 1998 Regulatory class: II 21 CFR 892.1000/Procode: 90 LNH

Dear Ms. Loar:

Sonja Barton Loar

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 (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 requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic OS 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.

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 market 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) 594-4613. 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/cdrb/dsmalan.html".

Sincerely yours,
Kiliani Yin

Lillian Yin, Ph.D. Director, Division of Reproductive Abdominal, Ear, Nose and Throat and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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STATEMENT OF INDICATIONS FOR USE

K981398 510(k) Number (if known): ___

Device Name: AnatoMark Noninvasive Head Reference System

Indications For Use:

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

David G. Seyssom

(Division Sign-Off) Division of Reproductive, Abdominal, EN and Radiological Device 510(k) Number

Prescription Use
(Per 21 CFR 801.109) X

Over-The-Counter Use

Regulation Number and Section

§ 892.1000 Magnetic resonance diagnostic device.

(a)
Identification. A magnetic resonance diagnostic device is intended for general diagnostic use to present images which reflect the spatial distribution and/or magnetic resonance spectra which reflect frequency and distribution of nuclei exhibiting nuclear magnetic resonance. Other physical parameters derived from the images and/or spectra may also be produced. The device includes hydrogen-1 (proton) imaging, sodium-23 imaging, hydrogen-1 spectroscopy, phosphorus-31 spectroscopy, and chemical shift imaging (preserving simultaneous frequency and spatial information).(b)
Classification. Class II (special controls). A magnetic resonance imaging disposable kit intended for use with a magnetic resonance diagnostic device only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.