(283 days)
No
The description details a traditional opto-electronic system and microprocessor for calculating IOP based on physical principles of corneal flattening. There is no mention of AI, ML, or related concepts in the device description, intended use, or performance studies.
No.
The device is a diagnostic tool used for measuring intraocular pressure to aid in glaucoma screening and diagnosis. It does not provide any therapeutic intervention.
Yes
The "Intended Use / Indications for Use" section states that the device is "intended to be used for measuring intraocular pressure (IOP) of the human eye," and the "Device Description" section states that it is "designed to measure Intra Ocular Pressure (IOP) to aid in the screening and diagnosis of glaucoma." This clearly indicates its role in gathering information for diagnosis.
No
The device description explicitly details hardware components such as an air generation system (vacuum diaphragm pump, air reservoir, solenoid valve), a light source, and an opto-electronic platform. It also mentions an on-board microprocessor, indicating it is a physical device with integrated software, not a software-only device.
Based on the provided information, the Keeler TonoCare Tonometer is not an In Vitro Diagnostic (IVD) device.
Here's why:
- Intended Use: The intended use is to measure intraocular pressure (IOP) of the human eye. This is a direct measurement of a physical parameter within the body, not an analysis of a sample taken from the body (like blood, urine, or tissue).
- Device Description: The device operates by projecting a puff of air onto the cornea and measuring the reflection of light as the cornea flattens. This is a physical interaction with the eye, not a test performed on a biological sample.
- Lack of Biological Sample Analysis: The description does not mention the collection or analysis of any biological samples.
IVD devices are specifically designed to examine specimens derived from the human body to provide information for the diagnosis, prevention, monitoring, treatment, or alleviation of disease. The Keeler TonoCare Tonometer does not fit this definition. It is a medical device used for a physical measurement on the patient's eye.
N/A
Intended Use / Indications for Use
The Keeler TonoCare Tonometer is a hand-held, battery operated, non-contact tonometer intended to be used for measuring intraocular pressure (IOP) of the human eye with less than 3D in corneal astigmatism.
Product codes
HKX
Device Description
The Keeler TonoCare Tonometer is designed to measure Intra Ocular Pressure (IOP) to aid in the screening and diagnosis of glaucoma without contacting the eye.
The Keeler TonoCare Tonometer has been designed using the same ergonomics as the predicate device described in 510(k) submission K093298. Both products consist of an air generation system in the form of a vacuum Diaphragm pump, an air reservoir, a solenoid valve, a light source and an opto-electronic platform which is used for position detection and IOP measurement.
The basic concept of operation is the same. The user positions the instrument close to the patient's cornea using a targeting system. As the user moves the instrument closer to the patient, the reflection off the cornea from the built-in light source increases until the predefined firing thresholds on the built-in photodiodes have been met. Once this condition has been met, a quantized puff of air is automatically projected toward the patient's cornea. As the cornea flattens due to the force of the puff of air, the light being reflected off of the cornea changes shape which in turn changes the profile of the light being reflected back onto the photodiodes. The rate of change of this reflection is monitored by the photodiodes and converted into intraocular pressure in units of mmHg by the on-board microprocessor.
Mentions image processing
Not Found
Mentions AI, DNN, or ML
Not Found
Input Imaging Modality
Not Found
Anatomical Site
human eye
Indicated Patient Age Range
Subjects must be over 18 years of age
Intended User / Care Setting
Not Found
Description of the training set, sample size, data source, and annotation protocol
Not Found
Description of the test set, sample size, data source, and annotation protocol
Not Found
Summary of Performance Studies (study type, sample size, AUC, MRMC, standalone performance, key results)
Repeatability and Reproducibility
Repeatability and reproducibility of TonoCare were assessed by measuring a manometrically controlled test eye.
Repeatability was measured using a single TonoCare device and a series of approximately 50 individual readings for each of 5 pressure values spaced evenly between the 5 to 50 mmHg working range. Readings were cross referenced with a reference pressure meter and a Pulsair Intellipuff device. Failed readings were rejected and averages of 3 subsequent readings were calculated to give a set of approximately 16 measurements at each of the 5 pressure values. Results demonstrate standard deviations ranging from 0.14 mmHg within the 5 to 50 mmHg pressure range respectively.
Reproducibility was assessed by analyzing measurements from three different TonoCare units by two different operators across 5 pressure values spaced evenly between the 5 to 50 mmHg working range. Two measurements (an average of 4 readings) at the 5 pressure values were taken for each of the six test cases (each operator using each of the three TonoCare devices). An Analysis of Variance (ANOVA) conducted on the data indicates a p-value of less than 0.05 and an R-square value of 98% or 99%, which signifies excellent reproducibility across operator and across devices.
Clinical Performance Data
The study conducted was a single visit, single-center, non-randomized, non-masked paired crossover study. The study obtained IOP measurements on each eligible eye with the TonoCare and the reference standard Perkins tonometer.
Two experienced observers acquired data from 144 qualifying eyes, measuring IOPs ranging from 7 mmHg – 23 mmHg in 50 participants and IOPs greater than 23 mmHg in 22 participants.
A total of 74 eligible participants were recruited, with 2 participants (2.7%) excluded. The reason for exclusion of two patients was due to excessive blinking or anxiousness resulting in the participant holding their breath. From the included 72 participants, IOP was measured in both eyes of all participants with TonoCare and Perkins AT, giving paired IOP measurements for a total of 144 eyes.
The results of the study show that the IOP measurements taken with the TonoCare NCT when compared to the reference Perkins tonometer (AT) do not exceed the ±5 mmHg tolerance in the three IOP ranges in 143 eyes with only 1 eye exceeding this tolerance for IOP measured >23 mmHg. This falls well below the requirement that no more than 5% of the paired differences between TonoCare and the reference tonometer should be outside the ±5 mmHg tolerance in the three IOP ranges.
Overall the mean of IOP differences between TonoCare and Perkins AT was
§ 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.
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February 8, 2019
Keeler Instruments Inc. Claudia Hill Marketing Director 3222 Phoenixville Pike Malvern, PA 19355
Re: K181143
Trade/Device Name: Keeler TonoCare Tonometer Regulation Number: 21 CFR 886.1930 Regulation Name: Tonometer And Accessories Regulatory Class: Class II Product Code: HKX Dated: January 4, 2019 Received: January 7, 2019
Dear Claudia Hill:
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 mav, therefore, market the device, subject to the general controls provisions of the Act. Although this letter refers to your product as a device, please be avare that some cleared products may instead be combination products. The 510(k) Premarket Notification Database located at https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpmn/pmn.cfm identifies combination product submissions. 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 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
1
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); medical device reporting (reporting of medical device-related adverse events) (21 CFR 803) for devices or postmarketing safety reporting (21 CFR 4, Subpart B) for combination products (see https://www.fda.gov/CombinationProducts/GuidanceRegulatoryInformation/ucm597488.html; good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820) for devices or current good manufacturing practices (21 CFR 4, Subpart A) for combination products; and, if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.
Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 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 comprehensive regulatory information about mediation-emitting products, including information about labeling regulations, please see Device Advice (https://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/) and CDRH Learn (http://www.fda.gov/Training/CDRHLearn). Additionally, you may contact the Division of Industry and Consumer Education (DICE) to ask a question about a specific regulatory topic. See the DICE website (http://www.fda.gov/DICE) for more information or contact DICE by email (DICE@fda.hhs.gov) or phone (1-800-638-2041 or 301-796-7100).
Sincerely yours,
Bradley S. Cunningham -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
2
Indications for Use
510(k) Number (if known) K181143
Device Name Keeler TonoCare Tonometer
Indications for Use (Describe)
The Keeler TonoCare Tonometer is a hand-held, battery operated, non-contact tonometer intended to be used for measuring intraocular pressure (IOP) of the human eye with less than 3D in corneal astigmatism.
| Type of Use (Select one or both, as applicable) | |
|---|---|
| ☑ Prescription Use (Part 21 CFR 801 Subpart D) | |
| ☐ Over-The-Counter Use (21 CFR 801 Subpart C) |
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Ophthalmic Instruments
510(k) Summary Keeler Non-Contact Tonometer Product Family
1. Submitter Contact Information
| Company Name/Address: | Keeler Instruments Inc
3222 Phoenixville Pike,
Building 50
Malvern,
PA 19355
USA |
|-------------------------|-------------------------------------------------------------------------------------------------|
| CONTACT PERSON: | Claudia Hill
Quality & Regulatory Manager |
| COMPANY PHONE NO.: | (610) 889 0200 |
| COMPANY FAX NO.: | (610) 889 3233 |
| DATE PREPARED: | April 23, 2018 |
| MANUFACTURING LOCATION: | Keeler Ltd
Clewer Hill Road, Windsor, Berkshire
SL4 4AA.
United Kingdom. |
| CONTACT PERSON: | Ms. Moria Zigman
Senior Regulatory Officer |
| COMPANY PHONE NO.: | (44) 1753 857177 |
| COMPANY FAX NO.: | (44) 1753 827145 |
2. Subject Device Information
| DEVICE TRADE NAME: | Keeler TonoCare Tonometer |
|---|---|
| COMMON NAME: | Tonometer |
| DEVICE CLASS: | Class II |
| CLASSIFICATION PANEL: | Ophthalmic |
| PRODUCT CODE: | HKX |
| REGULATION NUMBER: | 886.1930 |
Predicate Device Description 3.
| PRIMARY PREDICATE DEVICE: | Keeler Pulsair IntelliPuff Tonometer |
|---|---|
| 510(K) REFERENCE: | K093298 |
| SUBMISSION APPROVAL DATE: | 10/12/2010 |
| REFERENCE DEVICE: | Accutome Tonometer |
| 510(K) REFERENCE: | K083377 |
| SUBMISSION APPROVAL DATE: | 07/27/2009 |
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4. DEVICE DESCRIPTION:
The Keeler TonoCare Tonometer is designed to measure Intra Ocular Pressure (IOP) to aid in the screening and diagnosis of glaucoma without contacting the eye.
The Keeler TonoCare Tonometer has been designed using the same ergonomics as the predicate device described in 510(k) submission K093298. Both products consist of an air generation system in the form of a vacuum Diaphragm pump, an air reservoir, a solenoid valve, a light source and an opto-electronic platform which is used for position detection and IOP measurement.
The basic concept of operation is the same. The user positions the instrument close to the patient's cornea using a targeting system. As the user moves the instrument closer to the patient, the reflection off the cornea from the built-in light source increases until the predefined firing thresholds on the built-in photodiodes have been met. Once this condition has been met, a quantized puff of air is automatically projected toward the patient's cornea. As the cornea flattens due to the force of the puff of air, the light being reflected off of the cornea changes shape which in turn changes the profile of the light being reflected back onto the photodiodes. The rate of change of this reflection is monitored by the photodiodes and converted into intraocular pressure in units of mmHg by the on-board microprocessor.
The Keeler TonoCare Tonometer was launched into the European market in April 2018.
5. INDICATIONS FOR USE:
The Keeler TonoCare Tonometer is a hand-held, battery operated, non-contact tonometer intended to be used for measuring intraocular pressure (IOP) of the human eye with less than 3D in corneal astigmatism.
6. SUMMARY OF TECHNOLOGICAL CHARACTERISTICS:
The Keeler TonoCare Tonometer and Keeler Pulsair IntelliPuff (K093298) are two variants of the same family of Keeler non-contact air impulse tonometers and their technological features are substantially equivalent with regards to the optical system, optoelectronic devices, electronics, pneumatic system, contained software, measurement technique, calibration technique, safety, effectiveness and intended use.
Previously not utilized in the Keeler Pulsair IntelliPuff, the Tonometer allows for adjusted IOP calculations, as in the Accutome Tonometer (K083377), also referred to as CCT Correction. However, the accuracy of IOP measurements is known to be affected by variations and changes in corneal rigidity due to differences in corneal thickness, intrinsic structural factors or corneal refractive surgery. It is recommended that these factors are considered during IOP measurement. The biomechanical properties of an individual cornea may vary, resulting in changes of the relative stiffness or rigidity of the cornea and altering the measurement. Other factors to consider include corneal edema and other corneal abnormalities potentially affecting rigidity (e.g., keratoconus, corneal transplant, crosslinking) in addition to intrinsic structural factors and corneal refractive surgery.
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Ophthalmic Instrumer
Both the Keeler TonoCare Tonometer and Keeler Pulsair IntelliPuff (K093298) use different methods to generate and then deliver the puff of air with a known pressure time profile, but how the pressure in the chamber behind the puff tube is generated is immaterial to the measurement.
Most importantly the detection/viewing system has been deconstructed from the one system for both positioning and applanation detention functions in the Keeler Pulsair InteilliPuff (K093298) into two adjoining systems for the Keeler TonoCare Tonometer. This was done without changing the fundamental operating principles, in order to improve accuracy and repeatability as well as ease of use.
7. SUMMARY OF NON-CLINAL TESTS SUBMITTED:
Electrical safety and EMC testing were conducted on the Keeler TonoCare Tonometer and the device complies with IEC60601-1 and IEC60601-1-2 for EMC. Biocompatibility of the patient and user contacting materials was conducted in accordance with ISO10993-1. The risk management process was evaluated in accordance with ISO14971. Bench testing was conducted to demonstrate repeatability, reproducibility, and equivalency to the predicate device.
8. PERFORMANCE TESTING- CLINICAL PERFORMANCE
Repeatability and Reproducibility
Repeatability and reproducibility of TonoCare were assessed by measuring a manometrically controlled test eye.
Repeatability was measured using a single TonoCare device and a series of approximately 50 individual readings for each of 5 pressure values spaced evenly between the 5 to 50 mmHg working range. Readings were cross referenced with a reference pressure meter and a Pulsair Intellipuff device. Failed readings were rejected and averages of 3 subsequent readings were calculated to give a set of approximately 16 measurements at each of the 5 pressure values. Results demonstrate standard deviations ranging from 0.14 mmHg within the 5 to 50 mmHg pressure range respectively.
Reproducibility was assessed by analyzing measurements from three different TonoCare units by two different operators across 5 pressure values spaced evenly between the 5 to 50 mmHg working range. Two measurements (an average of 4 readings) at the 5 pressure values were taken for each of the six test cases (each operator using each of the three TonoCare devices). An Analysis of Variance (ANOVA) conducted on the data indicates a p-value of less than 0.05 and an R-square value of 98% or 99%, which signifies excellent reproducibility across operator and across devices.
Clinical Performance Data
Summary
The Keeler TonoCare Non-Contact Tonometer (NCT) was compared with the Perkins Applanation Tonometer (AT) in order to assess whether the TonoCare meets the requirements of ISO 8612 (comparable to ANSI Z80.10) in design compliance testing.
The Perkins AT uses the same basic principle as the Goldmann AT, namely, varying the force applied to applanate a fixed area of the cornea. Both instruments have an applanating 'cone' comprised of two prisms with apices joined together to apply an external force to the cornea to
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Ophthalmic Instrumer
indent and flatten its surface. There are several scientific articles referring to both instruments as reference standard tonometers and specifically the Perkins AT as the portable counterpart to the Goldmann AT (Wessels, I.F et al., 1990), (Carlos Garcia-Resua et al 2006), useful in domiciliary visits and for patients with mobility issues.
Two experienced observers acquired data from 144 qualifying eyes, measuring IOPs ranging from 7 mmHg – 23 mmHg in 50 participants and IOPs greater than 23 mmHg in 22 participants.
The results of the study show that the IOP measurements taken with the TonoCare NCT when compared to the reference Perkins tonometer (AT) do not exceed the ±5 mmHg tolerance in the three IOP ranges in 143 eyes with only 1 eye exceeding this tolerance for IOP measured >23 mmHg. This falls well below the requirement that no more than 5% of the paired differences between TonoCare and the reference tonometer should be outside the ±5 mmHg tolerance in the three IOP ranges.
Overall the mean of IOP differences between TonoCare and Perkins AT was 3D)
- ・ Corneal scarring, corneal surgery (including laser corneal surgery)
- Microphthalmosis ・
- . Buphthalmos
- . Contact lens wearers
- Dry eyes ・
- . Lid squeezers
- . Nystagmus
- ・ Keratoconus
- . Any other corneal or conjunctival pathology or infection
A total of 74 eligible participants were recruited, with 2 participants (2.7%) excluded. The reason for exclusion of two patients was due to excessive blinking or anxiousness resulting in the participant holding their breath. From the included 72 participants, IOP was measured in both eyes of all participants with TonoCare and Perkins AT, giving paired IOP measurements for a total of 144 eyes.
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Results
Table 1 below gives summary of IOP characteristics of the group, showing measurements to have similar distributions.
| TonoCare | Perkins AT | |
|---|---|---|
| N, eyes (patients) | 144 (72) | 144 (72) |
| Mean IOP, mmHg | 21.2 | 21.2 |
| Median IOP, mmHg | 18.0 | 17.0 |
| SD*, mmHg | 7.9 | 8.0 |
| Range, mmHg | 11.8 to 46.3 | 11.0 to 41.0 |
| IOP 7 to 16 mmHg, n (%)† | 42 (29.2) | 51 (35.4) |
| IOP 17 to 23 mmHg, n (%)† | 58 (40.3) | 49 (34.0) |
| IOP >23 mmHg**, n (%)† | 44 (30.6) | 44 (30.6) |
Table 1: Summary of TonoCare and Perkins AT IOP measurements
No pairing structure is summarized in this table. *Standard deviation, †Only Perkins AT IOP categories are used for sub-group analyses, n is given in terms of eyes. **In order to obtain measurements in this range, an inversion procedure was performed on a subset of participants while taking IOP measurements
Table 2 below categorizes the absolute differences between TonoCare and Perkins AT IOP measurements >5 mmHg overall, and within 3 IOP subgroups. A difference greater than the tolerance of ±5 mmHg occurred in 1 (0.7%) eye out of 144, well below the maximum level of 5% according to the standard.
Table 2: Differences between TonoCare and Perkins AT IOP measurements >5 mm Hg overall, and within 3 IOP subgroups.
| IOP Group† | |||||
|---|---|---|---|---|---|
| 7 to 16 mmHg | 17 to 23 mmHg | >23 mmHg** | Total | ||
| Difference* | Does not exceed ±5 mm Hg | 51 | 49 | 43 | 143 |
| Exceeds ±5 mmHg | 0 | 0 | 1 | 1 | |
| Total | 51 | 49 | 44 | 144 |
*IOP TonoCare – IOP Perkins AT, †Based on Perkins AT measured IOP
**In order to obtain measurements in this range, an inversion procedure was performed on a subset of participants while taking IOP measurements
Summary parameters of differences between pairs of TonoCare and Perkins AT IOP measurements are given in Table 3 below, for the full sample and by each IOP group. Overall the mean of IOP differences between TonoCare and Perkins AT was 23 mmHg**
(n=44) | Overall
(n=144) |
| Mean | 0.3 | 0.2 | -0.6 | 0.0 |
| Median | 0.2 | 0.2 | -0.9 | -0.2 |
| SD* | 1.3 | 1.5 | 2.1 | 1.7 |
| IQR§ | -0.4 to 1.2 | -0.8 to 1.0 | -1.8 to 0.1 | -1.0 to 1.0 |
| Range | -3 to 4 | -4.0 to 4.0 | -3.8 to 6.2 | -4.0 to 6.2 |
Table 3: Summary measures of IOP differences taken with TonoCare and Perkins AT measurements, summarized overall, and within 3 IOP subgroups.
+Based on Perkins AT measured IOP, * Standard deviation, §Interquartile range
**In order to obtain measurements in this range, an inversion procedure was performed on a subset of participants while taking IOP measurements
It was concluded by the investigators that there are no clinically meaningful differences in IOP measurements among the tonometers, and that the TonoCare conforms to the standard as detailed.
Method used for calibration of test device
The TonoCare Tonometer unit was initially cross calibrated on several rubber eyes against Keeler Pulsair IntelliPuff (K093298).
In addition, a mini trial on volunteers have been conducted to further refine the calibration of the TonoCare Tonometer in order to minimize the error between the devices.
In regards to Perkins Goldman Applanation Tonometer- it has been acquired from Haag-Streit as the reference tonometer.
Accuracy of Measurements
Accurately assessing IOP is of great importance for the diagnosis, detection and possible need for referral and treatment of Glaucoma.
The Keeler TonoCare NCT was compared with the Perkins AT in order to assess whether the TonoCare meets the requirements of ISO 8612 (comparable to ANSI Z80.10) in design compliance testing.
Two experienced observers acquired data from 144 qualifying eyes, measuring IOPs ranging from 7 mmHg – 23 mmHg in 50 participants and IOPs greater than 23 mmHg in 22 participants.
The results of the study show that the IOP measurements taken with the TonoCare NCT when compared to the reference Perkins tonometer (AT) do not exceed the ±5 mmHg tolerance in the three IOP ranges in 143 eyes with only 1 eye exceeding this tolerance for IOP measured >23 mmHg. This falls well below the requirement that no more than 5% of the paired differences between TonoCare and the reference tonometer should be outside the ±5 mmHg tolerance in the three IOP ranges.
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Ophthalmic Instruments
Overall the mean of IOP differences between TonoCare and Perkins AT was