MAYFIELD RADIOLUCENT SKULL PINS, MODEL 4-0-A-2020 by OHIO MEDICAL INSTRUMENT CO., INC.

Intended Use: MAYFIELD® Radiolucent Skull Pins are used with a skull clamp that is placed on the patient's skull to hold their head and neck in a particular position during surqical procedures when rigid skeletal fixation is desired and Intra-Operative CT or MRI imaging is used.

Indications for Use: The MAYFIELD® Radiolucent Skull Pins are indicated for use in open and percutaneous craniotomies and spinal surgeries when rigid skeletal fixation is necessary and when Intra-Operative CT or MRI imaging of the patient is used.

Device Description

The MAYFIELD Radiolucent Skull Pin 4-0-A-2020 [radiolucent pin] consists of the following components: a molded black-color ABS plastic base, and a machined sapphire-crystal pin point. The radiolucent pins are packaged three (3) pins per pouch, two (2) pouches per carton and EO sterilized. The radiolucent pins are single-use devices used to rigidly fix the patient's head and/or spine during surgery. The radiolucent pins are assembled from two components; a molded ABS plastic base [the same as used in the predicate device, MAYFIELD Disposable Skull Pins 4-0-A-1072][A1072 pins] and a pin point made of sapphire crystal that is machined to the same dimensions as the A1072 pin point. In preparation for surgery three (3) radiolucent pins are installed in a MAYFIELD Radiolucent Skull Clamp; two radiolucent pins in the Rocker Arm side and a single radiolucent pin on the opposite side. The radiolucent pins are EO sterilized, just as the A1072 pins mentioned above, and are ready for use right from the sterile pouch.

AI/ML Overview

The provided document describes the acceptance criteria and a study comparing the MAYFIELD® Radiolucent Skull Pins (4-0-A-2020) to a predicate device, the MAYFIELD Disposable Skull Pins (4-0-A-1072, K923789).

Here's a breakdown of the requested information:

1. Acceptance Criteria and Reported Device Performance

The acceptance criteria for the new device were based on demonstrating substantial equivalence to the predicate device in terms of performance, with an additional benefit in CT/MRI compatibility.

Acceptance Criteria Category	Specific Criteria	Reported Device Performance (MAYFIELD® Radiolucent Skull Pins)
Mechanical Performance	Penetration Testing (Axial Load): Repeated penetrations with no degradation of the pin point.	Results of comparisons of Penetration Testing with Axial Loading demonstrate that the radiolucent pins perform substantially the same as the predicate device. Multiple tests showed no device failures and performance equal to the predicate device.
	Penetration Testing (Axial & Shear Load): Sustained side forces exceeding a safety factor of 2.	Results of comparisons of Penetration Testing with Axial Loading and Shear Loading demonstrate that the radiolucent pins perform substantially the same as the predicate device. Multiple tests showed no device failures and performance equal to the predicate device.
Imaging Compatibility	CT/MRI Artifact Reduction: Significantly less artifact compared to the predicate device when used with intra-operative CT or MRI imaging.	Results of comparisons of CT Images of a melon held by radiolucent pins and a melon held by stainless steel pins [predicate device] show significantly less artifact resulting with the radiolucent pins than with the stainless steel [predicate device] pins. This demonstrates superiority in this specific aspect.
Material Equivalence	Base Material: Same as predicate device (ABS plastic).	The radiolucent pins utilize the same molded base made of the same ABS plastic material as the predicate device.
Manufacturing Process	Machining and Molding: Pin point machined to same dimensions as predicate; base molded to same dimensions as predicate.	The pin point is machined to the dimensions listed on the radiolucent pin point drawing, which lists the same dimensions as the stainless steel pin point drawing. The pin base is the same as the pin base used for the predicate device and is molded to the dimensions listed on the pin base drawing.
Sterilization	Method and SAL: Sterilized using a validated Ethylene Oxide sterilization cycle based on ANSI/AAMI/ISO 11135-1994, with a Sterility Assurance Level (SAL) of 10⁻⁶. Packaging suitable for sterile surgical devices.	The radiolucent pins are supplied sterile and are cleaned, assembled, packaged, and sterilized in exactly the same manner as the predicate device, using a validated Ethylene Oxide sterilization cycle (ANSI/AAMI/ISO 11135-1994) with an SAL of 10⁻⁶. Packaging is industry standard medical-grade, same as the predicate.
Intended Use / Indications	Substantially equivalent to the predicate device, with the additional mention of intra-operative CT or MRI imaging.	The intended uses and indications for use are identical to the predicate device, with the specific exception that the radiolucent pins are indicated for use when Intra-Operative CT or MRI imaging is used.
Method of Use	Three pins installed in receptacles of a MAYFIELD Skull Clamp.	Three (3) pins are installed in receptacles of a MAYFIELD Radiolucent Skull Clamp 4-0-A-2002 (or MAYFIELD 2000 Skull Clamp 4-0-A-2000 for the predicate), which is consistent with the method of use for the predicate device.

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

Sample Size: The document does not specify a precise numerical sample size for the "test set" in terms of how many pins were tested for mechanical performance. It states "Multiple Penetration Tests" were run. For the CT imaging comparison, it mentions "CT Images of a melon held by radiolucent pins and a melon held by stainless steel pins." This suggests at least one comparison image set, but not a large, statistically robust sample.
Data Provenance: The nature of the tests (mechanical and imaging on a melon) suggests these were lab-based, engineering tests rather than clinical data. Therefore, there's no mention of country of origin of data or whether it was retrospective or prospective. It is entirely prospective in the sense that the tests were conducted specifically for this submission.

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

Not applicable. The "ground truth" for these tests was objective, quantifiable measurements of mechanical integrity and image artifact, not expert interpretation. For example, "no degradation of point" or "sustained side forces exceeding safety factor" are engineering standards, and "significantly less artifact" would be based on image analysis, not expert consensus on pathology.

4. Adjudication method for the test set

Not applicable. The tests performed are objective engineering and imaging comparisons, not involving human interpretation that would require adjudication.

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. The tests described are for a medical device (skull pins), not an AI algorithm. Therefore, no MRMC study or assessment of human reader improvement with AI assistance was conducted or mentioned.

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

Not applicable. This is not an AI algorithm. The performance evaluation is for the physical device.

7. The type of ground truth used

The ground truth used was based on objective engineering measurements and imaging data analysis.

For mechanical performance (Penetration Tests): The ground truth was defined by physical parameters such as "no degradation of point" and "sustained side forces exceeding safety factor of 2," which are quantifiable engineering metrics.
For imaging compatibility: The ground truth was based on the direct comparison of image artifacts in CT scans, visually and potentially quantitatively assessed as "significantly less artifact."

8. The sample size for the training set

Not applicable. This is a medical device, not a machine learning model, so there is no concept of a "training set."

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

Not applicable, as there is no training set for this device.

Summary

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Image /page/0/Picture/1 description: The image shows the logo for Ohio Medical Instrument Company, Inc. The logo includes a caduceus symbol on the left, followed by the text "OMII" with a registered trademark symbol. To the right of the logo, the text "JUL 2 9 2002" is printed.

II. 510(k) SUMMARY

Summary of Safety and Effectiveness:

MAYFIELD® Radiolucent Skull Pins 4-0-A-2020

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

Summary Preparation Date: April 19, 2002

1. General Information:
  Classification Name: Holder, Head, Neurosurgical (Skull Clamp) Common/Usual Name: Skull Pins MAYFIELD® Radiolucent Skull Pins Proprietary Name:

Applicant's/Submitter's Name and Address & Registration Number:

Ohio Medical Instrument Company, Inc. (OMI) 4900 Charlemar Drive Cincinnati, OH 45227

Registration Number: 1525725 Contact Name: Charles E. Dinkler II Contact Title: New Product Development Engineer Contact Phone Number: (513) 561-2241 ext. 2002 Contact Fax Number: (513) 332-2000

2. Name of predicate device(s):

MAYFIELD Disposable Skull Pin 4-0-A-1072 (K923789)

3. Classification:

§882.4460 Neurosurgical Head Holder (skull clamp). (a) Identification: A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures.

(b) Classification: Class II (performance standards).

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K021604

4. Performance Standards:

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

5. Intended Use and Device Description:

Intended Use:

MAYFIELD Radiolucent Skull Pins are used with a skull clamp that is placed on the patient's skull to hold their head and neck in a particular position during surqical procedures when rigid skeletal fixation is desired and Intra-Operative CT or MRI imaging is used.

Indications for Use:

The MAYFIELD Radiolucent Skull Pins are indicated for use in open and percutaneous craniotomies and spinal surgeries when rigid skeletal fixation is necessary and when Intra-Operative CT or MRI imaging of the patient is used.

Device Description:

The MAYFIELD Radiolucent Skull Pin 4-0-A-2020 [radiolucent pin] consists of the following components:

a molded black-color ABS plastic base, and
a machined sapphire-crystal pin point.

The radiolucent pins are packaged three (3) pins per pouch, two (2) pouches per carton and EO sterilized.

The radiolucent pins are single-use devices used to rigidly fix the patient's head and/or spine during surgery. The radiolucent pins are assembled from two components; a molded ABS plastic base [the same as used in the predicate device, MAYFIELD Disposable Skull Pins 4-0-A-1072][A1072 pins] and a pin point made of sapphire crystal that is machined to the same dimensions as the A1072 pin point. In preparation for surgery three (3) radiolucent pins are installed in a MAYFIELD Radiolucent Skull Clamp; two radiolucent pins in the Rocker Arm side and a single radiolucent pin on the opposite side. The radiolucent pins are EO sterilized, just as the A1072 pins mentioned above, and are ready for use right from the sterile pouch.

6. Summary of Substantial Equivalence:

The MAYFIELD Radiolucent Skull Pins 4-0-A-2020 are substantially equivalent to the following devices:

· The MAYFIELD Disposable Skull Pins 4-0-A-1072, K923789.

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6. Summary of Substantial Equivalence: (continued)

Indications:

· The indications for the MAYFIELD Radiolucent Skull Pins 4-0-A-2020 are identical to the indications for the predicate device, MAYFIELD Disposable Skull Pins 4-0-A-1072, currently marketed by OMI, with the following exception: The radiolucent pins are indicated for use when Intra-Operative CT or MRI imaging is used.

Design:

Both the radiolucent pins and the A1072 Pins are used in MAYFIELD Skull Clamps for surgical approaches that require rigid skeletal fixation.
· Both systems may be used to treat the same medical or surgical conditions of the brain and cervical spine.
· Both systems have essentially the same cautions and contraindications for use.
· Head fixation devices have been in common use for many years. The Skull Pin allows the user to fixate the skull in a clamping device for improved reliability of CT or MR scan data. Technological advances have increased the demand to perform intra-operative surgery scans, which requires minimal artifact and necessitates compatible hardware such as the radiolucent pins. It is anticipated that most neurosurgery physicians are extensively experienced in the use of a MAYFIELD Skull Clamp and MAYFIELD Disposable Skull Pins fthe predicate device] and are expected to adapt readily to the use of the MAYFIELD Radiolucent Skull Pins.

Materials:

· Both the radiolucent pins and the predicate device utilize the same molded base made of the same ABS plastic material, the same sterilizable TYVEK/flexible film pouch and the same other packaging materials that meet the various BS. ISO and ASTM standards. The radiolucent pin point is made from sapphire crystall crystal alumina [aluminum oxide] while the A1072 pin point is made of 17-4PH stainless steel.

Performance:

· Results of comparisons of Penetration Testing with Axial Loading, Penetration Testing with Axial Loading and Shear Loading demonstrate that the radiolucent pins perform substantially the same as the predicate device. Multiple Penetration Tests with Axial Loading and Penetration Tests with Axial Loading and Shear Loading were run with the radiolucent pins and with the predicate device. The tests' results show the radiolucent pins performance is equal to that of the predicate device. There were no device failures during these tests.
· Results of comparisons of CT Images of a melon held by radiolucent pins and a melon held by stainless steel pins [predicate device] show significantly less artifact resulting with the radiolucent pins than with the stainless steel [predicate device] pins.

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7. Packaging:

The MAYFIELD Radiolucent Skull Pins [radiolucent pins] are supplied in the same packaging that is used by the predicate devices - industry standard medical grade packaging [sealed TYVEK/flexible film pouches] suitable for sterile surgical devices. Cartons and shippers are of suitable design and materials to ensure product sterility, identification and protection from damage during shipping and storage and are the same as or equivalent to that used by the predicate device.

8. Sterilization:

The radiolucent pins are supplied to the surgeon STERILE, as are the predicate devices. These devices are cleaned by OMI using a validated process to remove manufacturing residue, then thev are assembled with the base, shipped to the contract assembler/packager where they are assembled/packaged in a controlled environment assembly/packaging area and sealed. The sealed pouches are then sterilized using a validated Ethylene Oxide sterilization cycle, based upon ANSI/AAMI/ISO 11135-1994. Medical Devices - Validation and Routine Control of Ethylene Oxide Sterilization and the corresponding European/British standard EN 550:1994. The Sterility Assurance Level (SAL) of the validated sterilization cycle is 10° (SAL 10°). The radiolucent pins are packaged and sterilized in exactly the same manner as are the predicate devices.

9. Conclusion:

The radiolucent pin points are machined and the plastic bases are molded, in exactly the same manner as are the predicate device [A1072 pins]. The radiolucent skull pins are then assembled, cleaned, assembled/packaged, and sterilized in exactly the same manner as are the predicate device [A1072 pins].

The Penetration Tests that were conducted comparing the radiolucent pins to the A1072 pins show them to be equivalent, and the CT Imaging artifact comparison show the radiolucent pins are superior to the predicate device [A1072 pins].

Based on the information provided above, Ohio Medical Instrument Company, Inc. considers the MAYFIELD Radiolucent Skull Pins 4-0-A-2020 to be substantially equivalent to the predicate device, MAYFIELD Disposable Skull Pins 4-0-A-1072.

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10. Comparison Table

FEATURE	MAYFIELDRadiolucent Skull Pins4-0-A-2020	MAYFIELDDisposable Skull Pins4-0-A-1072	SE?
Intended Uses:	• Used with the MAYFIELDRadiolucent Skull Clamp4-0-A-2002 to clamp the patient'sskull and hold the head and neckin position during surgicalprocedures in which Intra-Operative CT or MRI imaging isused.	• Used with the MAYFIELD 2000Skull Clamp 4-0-A-2000 to clampthe patient's skull and hold thehead and neck in position duringsurgical procedures.	YES
Indications forUse:	• Indicated for use in open andpercutaneous craniotomies andspinal surgeries when rigidskeletal fixation is necessary andwhen Intra-Operative CT or MRIimaging is used.	• Indicated for use in open andpercutaneous craniotomies andspinal surgeries when rigidskeletal fixation is necessary.	YES
Materials:	• The pin point is machinedsapphire crystal [aluminum oxide]and the molded base is ABSplastic.	• The pin point is machinedstainless steel and the moldedbase is ABS plastic.	YES
Manufacturing:	• The pin point is machined to thedimensions listed on theradiolucent pin point drawingwhich lists same dimensions asthe stainless steel pin pointdrawing.• The pin base is the same as thepin base used for the predicatedevice and is molded to thedimensions listed on the pin basedrawing.	• The pin point is machined to thedimensions listed on thestainless steel pin point drawing.• The pin base is molded to thedimensions listed on the pinbase drawing.	YES
Preparation forSurgery:	• None, the pins are supplied sterilein a 3-pack pouch, ready for use.	• None, the pins are suppliedsterile in a 3-pack pouch readyfor use.	YES
Method of Use:	• Three (3) pins are installed inreceptacles of a MAYFIELDRadiolucent Skull Clamp4-0-A-2002 [K953124]	• Three (3) pins are installed inreceptacles of a MAYFIELD 2000Skull Clamp 4-0-A-2000[K932807].	YES
Performance:	• Penetration Testing-Axial LoadRepeated penetrations with nodegradation of point.-Axial & Side LoadSustained side forces exceedingsafety factor of 2	• Penetration --Axial LoadRepeated penetrations with nodegradation of point.-Axial and Side LoadSustained side forcesexceeding safety factor of 2.	YES
K-Number:	• To Be Assigned	• K923789	YES
Manufacturer:	• Ohio Medical InstrumentCompany, Inc.	• Ohio Medical InstrumentCompany, Inc.	YES

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Image /page/5/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo features a stylized depiction of an eagle with three human profiles incorporated into its design. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" are arranged in a circular pattern around the eagle.

JUL 2 9 2002

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. Charles E. Dinkler II Ohio Medical Instrument Company, Inc. 4900 Charlemar Drive Cincinnati, Ohio 45227

Re: K021604

Trade/Device Name: Mayfield® Radiolucent Skull Pins Model 4-0-A-2020 Regulation Number: 882.4460 Regulation Name: Neurosurgical Head Holder (Skull Clamp) Regulatory Class: II Product Code: HBL Dated: May 6, 2002 Received: May 16, 2002

Dear Mr. Dinkler:

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate 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) that do not require approval of a premarket approval application (PMA), 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. Iisting 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 (PMA), 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 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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Page 2 - Mr. Charles E. Dinkler II

This letter will allow you to begin marketing your device as described in your Section 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 vou desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 21 CFR Part 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" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html

Sincerely yours,

L. Mark N. Millhiser

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

Enclosure

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510(k) Number (if known):

MAYFIELD® Radiolucent Skull Pins A-2020 Device Name:

Indications For Use:

The MAYFIELD® Radiolucent Skull Pins A-2020 are intended for use with a skull clamp that is placed on the patient's skull to hold their head and neck in a particular position during surgical procedures when rigid skeletal fixation is desired and Intra-Operative CT or MR imaging is used.

The MAYFIELD® Radiolucent Skull Pins A-2020 are Indicated for use in open and percutaneous craniotomies and spinal surgeries when rigid skeletal fixation is necessary and when Intra-Operative CT or MR imaging of the patient is used.

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Mark A. Millman

Division of General, Restorative and Neurological Devices

510(k) Number _

ﮐﮯ Prescription Use (Per 21 CFR 801.109)

Over-The-Counter Use

(Optional Format - 1 - 2 - 96)

Regulation Number and Section

§ 882.4460 Neurosurgical head holder (skull clamp).

(a)
Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures.(b)
Classification. Class II (performance standards).