K031733 · Nidek, Inc. · HKX · Dec 4, 2003 · Ophthalmic
Device Facts
Record ID
K031733
Device Name
NON-CONTACT TONOMETER, MODEL NT-4000
Applicant
Nidek, Inc.
Product Code
HKX · Ophthalmic
Decision Date
Dec 4, 2003
Decision
SESE
Submission Type
Traditional
Regulation
21 CFR 886.1930
Device Class
Class 2
Indications for Use
The Nidek Model NT-4000 is a non-contact tonometer that is intended for use in the measurement of intraocular pressure of the human eye.
Device Story
Non-contact tonometer measures intraocular pressure (IOP) by optically detecting corneal applanation caused by air puff. Device comprises main unit (screen, controls, joystick), measuring unit (air nozzle, photo-detector), and base unit (chinrest, printer). Used in clinical settings by eye care professionals. Features include Auto Alignment (automatic positioning/focusing), Automatic Puff Control (APC) to minimize air pressure based on prior measurements, and pulse-synchronized IOP measurement using forehead rest detector. Output displayed on 5-inch TFT screen and printed via thermal printer. Benefits include patient comfort through reduced air pressure and automated, smooth measurement process.
Clinical Evidence
No clinical data. Bench testing only, including electrical safety (EN 60601-1), electromagnetic compatibility (EN 60601-1-2), programmable electrical medical systems (EN 60601-1-4), and ophthalmic instrument standards (ISO 15004, JIS T7312).
Technological Characteristics
Non-contact air-puff tonometer. Components: air nozzle, photo-detector, chinrest, joystick, 5-inch TFT color display, thermal printer. Power: 100/120/230V, 50/60Hz. Dimensions: 260x487x457mm. Features: Auto-alignment (horizontal/vertical/focus), APC (Automatic Puff Control), pulse-synchronized measurement. Standards: EN 60601-1, EN 60601-1-2, EN 60601-1-4, ISO 15004, JIS T7312.
Indications for Use
Indicated for measurement of intraocular pressure of the human eye.
Regulatory Classification
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.
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# 510(k) SUMMARY Nidek Non-Contact Tonometer Model NT-4000
### SUBMITTER INFORMATION 1.
| A. | Company Name: | Nidek Incorporated |
|----|--------------------------------|----------------------------------------------------------------------|
| B. | Company Address: | 47651 Westinghouse Drive.<br>Fremont, CA 94539-7474 |
| C. | Company Phone:<br>Company Fax: | (510) 353-7719<br>(510) 226-5750 |
| D. | Contact Person: | Mr. Hiroshi Okada<br>Regulatory and QA Manager<br>Nidek Incorporated |
| E. | Date Summary Prepared: | May 16, 2003 |
## DEVICE IDENTIFICATION 2.
| A. | Classification Name: | Tonometer, AC-Powered |
|----|-------------------------|-------------------------------------------|
| B. | Trade/Proprietary Name: | Nidek Non-Contact Tonometer Model NT-4000 |
| C. | Device Classification: | Class II (per 21 CFR 886.1930) |
| D. | Product Code: | HKX |
#### 3. SUBSTANTIAL EQUIVALENCE
The Nidek Model NT-4000 is of comparable type and is substantially equivalent to the following predicate device:
| Predicate Device | Manufacturer | 510(k) No. | Date Cleared |
|-----------------------------------------|----------------|------------|---------------------|
| Model NT-1000 Non-<br>Contact Tonometer | Nidek Co. Ltd. | K913189 | October 15,<br>1991 |
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#### DEVICE DESCRIPTION 4.
The Nidek Model NT-4000 non-contact tonometer optically detects the momentary state of the cornea (applanated by air pressure) and measures intraocular pressure without touching the cornea.
The Model NT-4000 is comprised of main unit and a measuring unit that are provided on a base unit. Each unit contains the following components:
- MAIN UNIT: A screen, control panel, and joystick are provided on this unit. .
- MEASURING UNIT: The air nozzle and photo-detector are provided on this unit. .
- BASE UNIT: The chinrest and a printer are provided on this unit. .
The Model NT-4000 has the following features:
- 1. Auto Alignment Mode: When the measuring unit approaches the center of the pupil in this mode, the instrument automatically performs alignment in the up, down, left, and right directions, and focuses in the back and forth directions. The measurement then starts automatically.
- 2. Automatic Puff Control (APC) Function: The intraocular pressure measurement can be performed with the air pressure as low as possible. When the measurement range is set to "APC 40" or "APC 60", in the first measurement, the automatic shut-off function (which is to stop puffing air as soon as the light reflected from the cornea is detected) activates in order to eliminate excessive puffing. In the subsequent measurement, the APC function activates to perform the measurement with the minimum air pressure based on the former measurement data. As the patient's eye is protected from excessive air pressure, the patient's comfort level increases and continuous measurement can be performed smoothly.
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- 3. Pulse Synchronized Intraocular Pressure Measurement: In addition to the standard IOP measurement mode, the intraocular pressure measurement can be performed in synchronization with an arbitrary position of the pulse signal that is obtained by the detector in the forehead rest. When the signals of the pulse and the completion of the alignment are detected simultaneously, the pulse synchronized IOP measurement is executed. It is possible to select the point of a pulse (i.e., either peak, middle, or bottom) to which measurement will be synchronized.
#### 5. INTENDED USE
The Nidek Model NT-4000 is a non-contact tonometer that is intended for use in the measurement of intraocular pressure of the human eye.
#### TECHNOLOGICAL CHARACTERISTICS 6.
A comparison of the technological characteristics of the Nidek Non-Contact Tonometer Model NT-4000 and the predicate device has been performed, and the results are summarized in the table below. The results of this comparison demonstrate that the Nidek Non-Contact Tonometer Model NT-4000 has the same basic technological characteristics as the predicate device and is equivalent to the marketed predicate device. The differences between the Nidek Non-Contact Tonometer Model NT-4000 and the predicate device are insignificant and do not affect the safety or effectiveness of the device.
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:
| PREDICATE DEVICE COMPARISON TABLE | | Nidek Model NT-1000 |
|---------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------|
| | | K913189 |
| Specifications &<br>Characteristics | | |
| Manufacturer | Nidek Co. Ltd.<br>Japan | Nidek Co. Ltd.<br>Japan |
| Device Name | Non-Contact Tonometer Model<br>NT-4000 | Non-Contact Tonometer<br>Model NT-1000 |
| Indications For Use | The Nidek Model NT-4000 is a<br>non-contact tonometer that is<br>indicated for use in the<br>measurement of intraocular<br>pressure of the human eye. | NT-1000 allows one to<br>measure the intraocular<br>pressure by blowing air on the<br>cornea without touching<br>directly to the patient's eye. |
| MEASUREMENT | | |
| Measurement Range | 1 to 60 mmHg | 1 to 60 mmHg |
| Measurement Range<br>Setting | APC40<br>APC60<br>40<br>60 | APC30<br>APC60<br>30<br>60 |
| Working Distance | 11 mm | 11 mm |
| Automatic Puff Control<br>(APC) Feature | Yes | Yes |
| Pulse Synchronized<br>IOP Measurement<br>Function | Yes | No |
| Eyelid Detection<br>Function | Yes | No |
| PREDICATE DEVICE COMPARISON TABLE | | |
| | Nidek Model NT-4000 | Nidek Model NT-1000<br>K913189 |
| ALIGNMENT | | |
| Alignment Method | 1 alignment spot & focusing<br>indicator | 1 alignment spot & focusing<br>indicator |
| Inner Fixation Light | Green LED | Green LED |
| Automatic Movement<br>System | Yes:<br>Horizontal & vertical<br>directions; back & forth<br>directions; Pulse Synchronous<br>system (selection) | No; manual operation only |
| Alignment Mode | • F.AUTO: auto alignment,<br>auto focus, auto air puff).<br>• S.AUTO: auto alignment,<br>manual focus, auto air puff).<br>• MANUAL: manual<br>alignment, manual focus,<br>auto air puff). | • AUTO: auto alignment,<br>manual focus, auto air<br>puff.<br>• MANUAL: manual<br>alignment, manual focus,<br>auto air puff. |
| Operation Range by<br>Joystick | 36 mm back & forth; 86 mm<br>right & left; 28 mm up & down | 36 mm back & forth; 86 mm<br>right & left; 28 mm up &<br>down |
| DISPLAY / PRINTING | | |
| Screen | 5 inch TFT color display | 5 inch black & white display |
| Printer | Thermal line printer | Built-in thermal printer |
| POWER SPECIFICATIONS | | |
| Voltage | AC 100 / 120 / 230 V | AC 100 / 120 / 220 / 240 V |
| Frequencies | 50 / 60 Hz | 50 / 60 Hz |
| Power Consumption | 70VA maximum | 80VA maximum |
| DIMENSIONS & WEIGHT | | |
| Dimensions (W x D x<br>H) & Weight | 260 mm (W) x 487 mm (D) x<br>457 mm (H); approx. 17 kg | 260 mm (W) x 487 mm (D) x<br>440 mm (H); approx. 20 kg |
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#### 7. PERFORMANCE DATA
The following testing was performed on the Nidek Non-Contact Tonometer Model NT-4000 to demonstrate that it meets all specified requirements and is equivalent to the predicate device:
Electrical Safety Testing & Electromagnetic Compatibility A.
> The Nidek Non-Contact Tonometer Model NT-4000 was tested in accordance with EN 60601-1 and EN 60601-1-2, and was found to meet all requirements of both standards.
- Programmable Electrical Medical Systems B.
The Nidek Non-Contact Tonometer Model NT-4000 was tested in accordance with EN 60601-1-4 and was found to meet all requirements of the standard.
C. Test Requirements and Test Methods for Ophthalmic Instruments
> The Nidek Non-Contact Tonometer Model NT-4000 was tested in accordance with ISO 15004 and JIS T7312 and was found to meet all requirements of the standards.
#### CONCLUSIONS 8.
. .
Nidek Incorporated has demonstrated through its evaluation of the Nidek Non-Contact Tonometer Model NT-4000 that the device is equivalent to the predicate device with respect to intended use, technological characteristics, and safety and effectiveness.
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Image /page/6/Picture/1 description: The image shows the logo for the U.S. Department of Health and Human Services. The logo is circular in shape, with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" arranged around the perimeter of the circle. In the center of the circle is an abstract symbol that resembles a stylized caduceus, a symbol often associated with medicine and healthcare.
DEC - 4 2003
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
Nidek Incorporated c/o Ms. Carol L. Patterson Patterson Consulting Group, Inc. 21911 Erie Lane Lake Forest, CA 92630
Re: K031733
Trade/Device Name: Tonometer, AC-Powered Regulation Number: 21 CFR 886.1930 Regulatory Class: Class II Product Code: HKX Dated: June 3, 2003 Received: June 9, 2003
Dear Ms. Patterson:
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, 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 (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 - Ms. Carol L. Patterson
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 you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at (301) 594-4613. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). 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) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html
Sincerely vours.
Akeri Rosenthal
A. Ralph Rosenthal, 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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# INDICATIONS FOR USE
KO31733 3 __ (To Be Assigned By FDA) 510(k) Number: Device Trade Name: Nidek Non-Contact Tonometer Model NT-4000 Indications For Use: The Nidek Model NT-4000 is a non-contact tonometer that is indicated for use in the measurement of intraocular pressure of the human eye.
PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)
Concurrence of CDRH, Office of Device Evaluation (ODE)
Prescription Use V (Per 21 CFR 801.109)
OR
Over-The-Counter Use
Denis L. McCarthy
Division of Ophthalmic Ear. Nose and Throat Devises
510(k) Number K031733
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