The Digital Keeler Applanation Tonometer is a screening device used to measure intraocular pressure which is one of the factors considered in diagnosing glaucoma. The product is an active medical device, powered by a single AA battery. The operation principal is based on Goldmann applanation method.

AI/ML Overview

The provided document describes the modification of a Keeler Applanation Tonometer (KAT) to a Digital Keeler Applanation Tonometer (D-KAT). The D-KAT is intended to provide a digital readout of intraocular pressure (IOP) as an alternative to the manual dial reading of the predicate device.

Acceptance Criteria and Reported Device Performance

The primary acceptance criterion described for the D-KAT is its measurement deviation, which is based on the Tonometer standard ISO 8612:2009. The device needs to achieve a measurement deviation comparable to the predicate device.

Acceptance Criteria	Reported Device Performance
Measurement Deviation: ±0.49 mN (~0.5mmHg) or 1.5% of measurement value, whichever is greater (in accordance with ISO 8612:2009)	The D-KAT instrument has been validated to a measurement deviation of ±0.49mN (~0.5mmHg) or 1.5%, whichever is greater, in accordance with ISO 8612:2009.
Compliance with IEC 60601-1 (Electrical Safety)	Device has been tested to meet IEC 60601-1 Electrical Safety requirements.
Compliance with IEC 60601-1-2 (EMC)	Device has been tested to meet IEC 60601-1-2 EMC requirements.
Software designed and developed in accordance with ISO 62304	The software has been designed and developed in accordance with ISO 62304 Medical device software - Software life-cycle processes.
Essential requirements and test methods for ophthalmic instruments (ISO 15004-1)	Assessed and/or tested to ISO 15004-1:2006.
Symbols to be used with medical devices (ISO 15223-1)	Assessed and/or tested to ISO 15223-1:2012.
Biological evaluation of medical devices (ISO 10993-1)	Assessed and/or tested to ISO 10993-1.
Risk management (ISO 14971)	Assessed and/or tested to ISO 14971:2007.

Study Details:

The provided document describes verification tests and compliance with various standards to demonstrate substantial equivalence to the predicate device, rather than a clinical study with human readers and AI.

Sample size used for the test set and the data provenance:
- Test Set Sample Size: Not explicitly stated as a number of patients or cases. The performance validation was conducted through "bench testing using a balance system" and "usability tests."
- Data Provenance: Bench testing would be laboratory data. Usability tests were conducted by healthcare professionals, implying an in-situ or simulated clinical environment. No specific country of origin is mentioned for the data, but the manufacturer is Keeler Instruments Inc. in the USA. The data is likely prospective for these validation tests.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- For the bench testing, the "ground truth" was established by applying "known pressures covering the measurement range" using calibration bars verified according to ISO 8612:2009. This relies on the accuracy of the calibration system rather than human experts.
- For the usability tests, "healthcare professionals" were involved, but their number and specific qualifications (beyond being healthcare professionals) are not detailed. Their role was to compare the D-KAT against the predicate device, not necessarily to establish ground truth for IOP measurements.
Adjudication method for the test set: Not applicable. The primary performance evaluation was bench testing against a standard, not a scenario requiring adjudication between human readers or device outputs.
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 document describes a medical device (tonometer) with a digital display, not an AI-powered diagnostic tool requiring MRMC studies to compare human reader performance with and without AI assistance.
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: The device itself is an "algorithm only" in the sense that the software processes the raw measurement to display the IOP. The "bench testing using a balance system" is a form of standalone performance evaluation for the device's accuracy in measuring force/pressure, conforming to the ISO standard.
The type of ground truth used:
- For measurement performance: The "known pressures" provided by a calibrated balance system, verified against ISO 8612:2009.
- For usability: Comparison against the predicate device by healthcare professionals. No objective "ground truth" for usability is described, rather a subjective comparison.
The sample size for the training set: Not applicable. The device is a measurement instrument, not an AI model that requires a training set in the conventional sense. The "software uses information stored / programmed during the factory setup / calibration" which could be considered akin to a "training" or calibration phase, but it's not a data-driven machine learning training set.
How the ground truth for the training set was established: Not applicable, as there is no training set in the typical machine learning context. The calibration information for the device's setup is established during "factory setup / calibration" by applying "known pressures" and relating them to the rotating measuring drum's position, as outlined in ISO 8612:2009.

Summary

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K 133234

Ophthalmir Instruments

FEB 2 1 2014

510(k) Summary of Safety and Effectiveness

Submitter Name and Address 1.

Keeler Instruments Inc. 459 Parkway Broomall PA 19008

Eugene R Van Arsdale (Marketing Manager) Contact: Phone: 1 610 353 4350 Fax: 1 610 353 7814 erv@keelerusa.com Email:

Date Prepared: 20 February 2014

2. Device Name (Unmodified)

Trade Name:

Common/Usual Name: T-Type KAT, R-Type KAT Classification Name: Tonometer and Accessories 886.1930 Regulation No: Device Requlatory Class: ============================================================================================================================================================================== Review Panel: Ophthalmic Product Code: HKY Premarket Notification (510(k)) Number: K093445

Proposed Modification

The proposed modification described in this Traditional 510(k) covers the introduction of a digital variant to the current Keeler Applanation Tonometer (KAT) range. This modification is intended to provide an addition to the Keeler Applanation Tonometers product range.

(KAT)

Keeler Applanation Tonometer

In applanation tonometry the intraocular pressure (IOP) is calculated from the force required to flatten a constant area of the cornea. Goldmann tonometry is considered to be the gold standard test and is the most widely accepted method in current practice.

The new digital variant of the KAT uses the same operating principle found in all Goldmann type tonometers.

The internal mechanism of the KAT has been modified to permit the measured IOP to be read on an LED display. The LED display allows for easy reading by the user rather than reading from the dial as is currently the case with standard Goldmann tonometers.

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thatmir Instruments

The intended use of the Digital Keeler Applanation Tonometer (D-KAT) as well as the method used by the clinician to obtain a reading remains unchanged by this modification.

4. Device Description

The Indications for Use, Operating principles, measurement accuracy and repeatability are the same as the predicate device. The device is used in conjunction with commercially available Slit lamps and can be used with the same mounting options as predicate device.

The D-KAT uses the same Applanation Prisms as the predicate Keeler Applanation Tonometer.

Method of Operation

In applanation tonometry the intraocular pressure is calculated from the force required to flatten a constant area of the cornea. Goldmann tonometry is considered to be the qold standard test and is the most widely accepted method in current practice.

The Digital Keeler Applanation Tonometer functions in accordance with the 'Goldmann method' i.e. the measuring of pressure to maintain a uniform i applanation of the surface of the eye.

A disinfected or sterile disposable applanation prism is mounted on the Tonometer head at the end of the measurement arm and then placed against the cornea. The examiner then uses a cobalt blue filter to view two green semi circles, known as mires. The force applied to the Tonometer head is then adjusted using the rotating measurement drum connected to a variable tension spring until the inner edges of the green mires in the viewfinder meet. When an area of 3.06mm has been flattened, the opposing forces of corneal rigidity and the tear film are roughly approximate and cancel each other out allowing the pressure in the eye to be determined from the force applied.

The intraocular pressure is presented on the digital display.

The D-KAT is used in coniunction with commercially available Slit Lamos and can be used with the same mounting options as the predicate devices.

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Calibration

During factory setup / calibration known pressures covering the measurement range are applied to the measurement arm using calibration bars verified using the calibration procedure outlined in the Tonometer standard ISO 8612:2009.

Calibration provides a relationship between the pressure applied to the measurement arm and the position of the rotating measuring drum. Linear interpolation is used between the calibration points.

It should be noted that whilst the D-KAT has a Digital read-out that can indicate decimal point measurement, it is not intended to imply higher accuracy. The D-KAT instrument has been validated to a measurement deviation of ±0.49mN (~0.5mmHg) or 1.5%, whichever is greater, in accordance with the above standard.

Software

The software uses information stored / programmed during the factory setup / calibration to monitor the position of the measurement arm against the position of the rotating measuring drum to determine the patients IOP, which is displayed to the user on the LED display.

5. Labelling and Intended Use

Instructions for use (IFU) for the applanation tonometer have been updated to incorporate the use of the digital interface.

The intended use of the Digital Keeler Applanation Tonometer (D-KAT) as well as the method used by the clinician to obtain a reading remains unchanged by this modification.

"The Keeler Applanation Tonometer is indicated for measuring intraocular pressure to aid in the screening and diagnosis of Glaucoma."

Materials Biocompatibility 6.

With respect to material that comes into direct contact intentionally with the eve, there are no changes.

Cleaning and Disinfection 7.

Cleaning instructions for the tonometer body and the recommended method for disinfecting applanation prisms remains unchanged.

Instructions have been provided in the Instructions for use.

8. Comparison of the device with the Predicate

The comparison table below summarizes the similarities and differences between both systems, with respect to safety and effectiveness, which are discussed in more detail in the following sections.

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Keeler

Ophthalmic Instruments

CharacteristicFeatures	Predicate Device -Keeler ApplanationTonometer(KAT)	Modified Device -Digital KeelerApplanationTonometer(D-KAT)	Notes
Type	Manual contactTonometer	Manual contactTonometer	No change
Indication	Intraocular Pressure(IOP) measurement	Intraocular Pressure(IOP) measurement	No change
Units ofmeasure	mmHg - millimetreof mercury	mmHg - millimetreof mercury	No change
Design	Slit lamp mountedmanual dial	Slit lamp mountedmanual dial	No change
MeasurementRange	0-80mmHg	5-65mmHg	A measurementrange of 0 -80mmHg is not arequirement for thisdeviceDevice meets therequirementsspecified in theTonometerstandard ISO8612:2009The modificationdoes not affect thesafety oreffectiveness of thedevice
Measurementtechnique	Applanation	Applanation	No change
MeasurementMethod	Goldmann method -the measuring ofpressure to maintaina uniformapplanation of thesurface of the eye.	Goldmann method -the measuring ofpressure to maintaina uniformapplanation of thesurface of the eye.	No change
Calibration	Maintenance andcalibration requiredFactory setCalibration armassembly is	Maintenance andcalibration requiredFactory setCalibration armassembly is	No change
	supplied with eachdevice to checkcalibration	supplied with eachdevice to checkcalibration
Intended use	The KeelerApplanationTonometer isindicated formeasuringintraocular pressureto aid in thescreening anddiagnosis ofGlaucoma.	The KeelerApplanationTonometer isindicated formeasuringintraocular pressureto aid in thescreening anddiagnosis ofGlaucoma.	No change
Mountingmethod on slitlamp	Fixed (R-Type) andTake-away (T-Type)	Fixed (R-Type) andTake-away (T-Type)	No change
Measurementdeviation	0.49 mN or 1.5% ofmeasurement value,whichever is thegreater	0.49 mN or 1.5% ofmeasurement value,whichever is thegreater	No change
Powerrequirements	None required –device ismechanical	AA Battery to powerdigital display	Device has beentested to meet IEC60601-1 ElectricalSafety and IEC60601-1-2 EMCrequirementsThe modificationdoes not affect thesafety oreffectiveness of thedevice
Software	None	Contains software	The software hasbeen designed anddeveloped inaccordance withISO 62304 Medicaldevice software -Software life-cycleprocessesA Calibration(verification) ArmAssembly issupplied with each
			the user to checkthe tonometer is incalibration.
			The modificationdoes not affect thesafety oreffectiveness of thedevice
Display	Analogue scale -Direct reading fromthe dial (eachdivision on dial ofrotating measuringknob is equal to0.2gmf (1.96mN))which is multipliedby 10 by the user tocalculate thepressure in mmHg	Numerical display -Direct reading ofIOP in mmHg fromdisplay	Both devicesgenerate a IOP inmmHg

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Keeler

Ophthalmic Instruments

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Keeler

Ophthalmic Instruments

9. Performance and Safety

Verification tests have been carried out to confirm that the performance and safety aspects of the modified Digital Keeler Applanation Tonometer (D-KAT) are comparable with the Keeler Applanation Tonometer cleared for marketing under 510(k) K093445. The results demonstrated that the modified D-KAT was substantially equivalent in relation to performance, usability and safety to the aforementioned predicate device.

With respect to performance of the modified tonometer, bench testing using a balance system was carried to verify the measuring force was in accordance with Section A2 of ISO 8612:2009, Ophthalmic Instruments - Tonometers.

Usability tests have also been conducted by healthcare professionals, where comparisons were made against the predicate device (K093445).

In accordance with the Keeler Software Quality Plan, the software used in the modified D-KAT has been verified against design requirements and finally released, as required by IEC 62304 Medical device software - Software life cvcle processes.

In addition to the above testing activities, Keeler has conducted assessment and/or testing to the following standards to further reinforce the safety and effectiveness of the modified D-KAT:

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eeler

Ophthalmic Instruments

	~ AAMI ANSI 60601-1:2005 Medical Electrical Equipment-Generalrequirements for safety and essentialperformance

IEC 60601-1-2:2007 Medical Electrical Equipment-Electromagnetic compatibility-Requirements and tests
ISO 15004-1:2006 Ophthalmic Instruments- Fundamental requirements and test methods Part 1: General requirements applicable to all ophthalmic instruments
ISO 15223-1:2012 Medical Devices: Symbols to be used with medical devices labels, labelling and information to be supplied-general requirements
Biological evaluation of medical devices: - ISO10993-1 Evaluation and testing within a risk management process
ISO14971:2007 Medical Devices-Application of risk management to medical devices

In all tests the modified device was in compliance with these FDA recognized standards.

10. Substantial Equivalence

The modified Digital Keeler Applanation Tonometer is considered to be substantially equivalent to the Keeler Applanation Tonometer described in the original 510(k) submission (K093445).

Digital Keeler Applanation Tonometer Traditional 510(k)

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DEPARTMENT OF HEALTH & HUMAN SERVICES

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February 21, 2014

Food and Drug Administration 10903 New Hampshire Avenue Document Control Center - WO66-G609 Silver Spring MD 20993-0002

Keeler Instruments, Inc. % Mr. Eugene R. VanArsdale Marketing Manager 456 Parkway Broomall, PA 19008-4295

Re: K133234

Trade/Device Name: Digital Keeler Applanation Tonometer (D-KAT) Regulation Number: 21 CFR 886.1930 Regulation Name: Tonometer and Accessories Regulatory Class: Class II Product Code: HKY Dated: January 6, 2014 Received: January 7, 2014

Dear Mr. VanArsdale:

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. Drye. 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, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration. Please note: CDRH does not evaluate information related to contract liability warranties. We remind you, however, that device labeling must be truthful and not misleading.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to 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 conceming 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.

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Page 2 - Mr. Eugene VanArsdale ﺑﻪ ﻣﺮﮐﺰ ﺩﺭ ﻣﯿ

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); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803); 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.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Division of Small Manufacturers, International and Consumer Assistance at its tollfree number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.goy/MedicalDevices/ResourcesforYou/Industry/default.htm. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). For questions regarding the reporting of adverse events under the MDR regulation (21 CFR Part 803), please go to

http://www.fda.gov/MedicalDevices/Safety/ReportaProblem/default.htm for the CDRH's Office of Surveillance and Biometrics/Division of Postmarket Surveillance.

You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 796-7100 or at its Internet address

http://www.fda.gov/MedicalDevices/ResourcesforYou/Industry/default.htm.

Sincerely yours,

Kesia Y. Alexander -S

for Malvina B. Eydelman, M.D. Director Division of Ophthalmic and Ear. Nose and Throat Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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Ophthelmic Instruments

Indications for Use Statement

510(k) Number (if known): K133234

Device Name: Digital Keeler Applanation Tonometer. (D-KAT)

Indications for Use:

The Keeler Applanation Tonometer is indicated for measuring intraocular pressure to aid in the screening and diagnosis of Glaucoma.

Prescription Use _____________________________________________________________________________________________________________________________________________________________ (21 CFR 801 Subpart C)

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

Concurrence of CDRH, Office of Device Evaluation (ODE)

Jan C. Callaway -S 2014.02.04 14:41:26 -05'00'

Regulation Number and Section

§ 886.1930 Tonometer and accessories.

(a)
Identification. A tonometer and accessories is a manual device intended to measure intraocular pressure by applying a known force on the globe of the eye and measuring the amount of indentation produced (Schiotz type) or to measure intraocular tension by applanation (applying a small flat disk to the cornea). Accessories for the device may include a tonometer calibrator or a tonograph recording system. The device is intended for use in the diagnosis of glaucoma.(b)
Classification. Class II.