Keeler D-KAT R User manual

Keeler Digital Applanation
Tonometer (D-KAT)
R-Type and T-Type
INSTRUCTIONS FOR USE
EN SK

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SK
D-KAT Tonometer
Instructions For Use.......................................................... 1
Tonometer D-KAT
Návod na použitie.......................................................... 25

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D-KAT Tonometer by KEELER
CONTENTS
1. INDICATIONS FOR USE ................................................................................................... 4
1.1 BRIEF DESCRIPTION OF THE INSTRUMENT............................................................................... 4
1.2 INTENDED USE / PURPOSE OF INSTRUMENT........................................................................... 4
1.3 HOW THE INTRAOCULAR PRESSURE (IOP) IS MEASURED............................................... 4
1.4 ADVANTAGES OF USING A GOLDMANN TYPE TONOMETER ........................................ 4
2. SAFETY.................................................................................................................................. 5
2.1 WARNINGS AND CAUTIONS............................................................................................................ 5
2.2 CONTRAINDICATION............................................................................................................................7
3. CLEANING AND DISINFECTION INSTRUCTIONS .......................................................7
3.1 CLEANING TONOMETER BODY........................................................................................................7
3.2 DISINFECTING THE TONOMETER PRISMS ................................................................................. 8
4. TONOMETER PRISM FIELD CHECK................................................................................ 9
5. NAME OF COMPONENTS ...............................................................................................10
6. SWITCHING ON / OFF AND CONFIGURING THE D-KAT ......................................10
6.1 SWITCHING ON / OFF........................................................................................................................10
6.2 CHANGING DECIMAL POINT SETTING.......................................................................................10
6.3 CHANGING THE VOLUME.................................................................................................................. 11
6.4 CHANGING THE DISPLAY BRIGHTNESS .....................................................................................11
6.5 BATTERY STATUS................................................................................................................................... 11
7. MEASUREMENT PROCEDURE .........................................................................................11
7.1 INSTALLATION ON TO THE SLIT LAMP.........................................................................................11
7.2 PREPARING THE PATIENT..................................................................................................................12
7.3 PREPARING THE SLIT LAMP INSTRUMENT FOR EXAMINATIONS AT 10X
MAGNIFICATION...................................................................................................................................13
7.4 USING THE INSTRUMENT / TAKING A MEASUREMENT......................................................13
8. PROBLEM SOLVING..........................................................................................................15
8.1 THE FLUORESCEIN RING IS TOO WIDE OR TOO NARROW.............................................15
8.2 THE MEASUREMENT PRISM DOES NOT TOUCH THE CORNEA OR TOO MUCH
FORCE HAS BEEN APPLIED...............................................................................................................15
8.3 THE TWO SEMICIRCLES ARE NOT CENTRAL IN THE FIELD OF VISION.......................16
8.4 THE INSIDE MARGINS OF THE FLUORESCEIN RINGS ARE NOT ALIGNED AND
TOUCHING ...............................................................................................................................................17
9. GENERAL INFORMATION AND SUGGESTIONS CONCERNING
MEASUREMENT .................................................................................................................18
10. ASTIGMATISM ...................................................................................................................18
11. ROUTINE INSTRUMENT MAINTENANCE.....................................................................19
11.1 CHECK PROCEDURE WITH TEST ARM SET TO 20................................................................19

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12. ROUTINE INSTRUMENT MAINTENANCE....................................................................20
12.1 CHECK PROCEDURE WITH TEST ARM SET TO 20...............................................................20
12.2 CHECK PROCEDURE WITH TEST ARM SET TO 60 ..............................................................20
13. SERVICING AND CALIBRATION.................................................................................... 21
13.1 BATTERY REPLACEMENT ...................................................................................................................21
14. WARRANTY ....................................................................................................................... 22
15. TECHNICAL SPECIFICATIONS...................................................................................... 22
16. ACCESSORIES AND SPARES ........................................................................................ 23
17. PACKAGING AND DISPOSAL INFORMATION..........................................................24

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D-KAT Tonometer by KEELER
Consult instructions for use General warning sign
Date of manufacture Warning: Non-ionizing radiation
Manufacturer’s name and
address Keep dry
Country of manufacture Fragile
Waste Electrical and Electronic
Equipment (WEEE) recycling Do not use if package is damaged
This way up Class II equipment
Temperature limit Atmospheric pressure limitation
Temperature limit Humidity limitation
0120
United Kingdom Conformity
Assessed, with the Notified
Body number for SGS UK 1639
Conformité Européene, with the
Notified Body number for SGS
Belgium NV
REPEC
Authorised representative in the
European Community
REPCH
Authorised representative in
Switzerland
Catalogue number Serial number
Translation Medical device
The Keeler D-KAT Tonometer is designed and built in conformity with Directive 93/42/EEC, Regulation (EU)
2017/745 and ISO 13485 Medical Devices Quality Management Systems.
Classification: CE / UKCA: Class IIa
FDA: Class II
The information contained within this manual must not be reproduced in whole or part without the manufacturer’s
prior written approval.As part of our policy for continued product development we the manufacturer reserve the right
to make changes to specifications and other information contained in this document without prior notice.
This IFU is also available on the Keeler UK and Keeler USA websites.
Copyright © Keeler Limited 2023. Published in the UK 2023.

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D-KAT Tonometer by KEELER
1. INDICATIONS FOR USE
These devices are intended to be used only by suitably trained and authorised healthcare
professionals.
CAUTION: Federal Law restricts this device to sale by or on the order of a
physician or practitioner.
1.1 BRIEF DESCRIPTION OF THE INSTRUMENT
The Keeler Applanation Tonometer operates according to the “Goldmann method”, by
measuring intraocular pressure from the force required to flatten (applanate) a constant
area (3.06 mm) of the cornea. A special disinfected (or single use) prism is mounted on the
Tonometer head and then placed against the cornea.
The examiner, using a slit lamp biomicroscope at 10x magnification, with a blue filter views
two fluorescing green semicircles. The force applied to the Tonometer head is then adjusted
using the dial until the inner edges of these green semicircles meet.
Because physical contact with the cornea takes place, it is necessary to apply to the patient’s
cornea a suitable topical anaesthetic.
1.2 INTENDED USE / PURPOSE OF INSTRUMENT
The Keeler Digital Applanation Tonometer is indicated for measuring intraocular pressure to aid
in the screening and diagnosis of glaucoma.
The Keeler Digital Applanation Tonometer (D-KAT) is an accessory item for most ‘Tower
Illumination’ type of Slit Lamps and thanks to its versatility, the D-KAT Tonometer can be
mounted on and used with slit lamps produced by many manufacturers.
1.3 HOW THE INTRAOCULAR PRESSURE (IOP) IS MEASURED
The cornea is flattened by an acrylic measuring prism
on a ring support at the end of the Tonometer sensor
arm assembly. It is flat with smooth or rounded
margins to avoid any damage to the cornea.
The measuring prism is brought into contact with
the patient’s eye by moving the slit lamp forward.
The measurement drum is then turned to increase
the pressure on the eye, until a continuous, uniform
applanated surface 3.06 mm in diameter (7,354 mm²
area) is obtained. The doubling prism divides the
image and presents the two opposing semicircular
halves at 3.06 mm (see section 13 on page 21
Measurement procedure for further details).
1.4 ADVANTAGES OF USING A GOLDMANN TYPE TONOMETER
• Intraocular pressure can be measured during a routine examination with the Slit Lamp.
• The standard deviation among single measurements is approximately ≤ 0,5 mmHg*.
LED
Display
mmHg
Force
mN
Pressure
kPa
10 9.81 1.33
20 19.62 2.66
30 29.43 3.99
40 39.24 5.32
50 49.05 6.65
60 58.86 7.98
Relationship between the LED display
and the force and pressure on the
applanated surface.

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D-KAT Tonometer by KEELER
• The value is expressed in mmHg and is read directly on the instrument.
• Scleral rigidity need not be taken into consideration because the small volume moved
(0,56 mm3) increases intraocular pressure by only about 2.5%.
*Please Note: 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 ISO 8612.
2. SAFETY
2.1 WARNINGS AND CAUTIONS
Please note that the proper and safe functioning of our instruments is only guaranteed if
both the instruments and their accessories are exclusively from Keeler Ltd. The use of other
accessories may result in increased electromagnetic emissions or reduced electromagnetic
immunity of the device and may lead to incorrect operation.
Observe the following precautions in order to ensure safe operation of the instruments.
WARNINGS
• Never use the instrument if visibly damaged and periodically inspect it for signs of damage
or misuse.
• Check your Keeler product for signs of transport / storage damage prior to use.
• US Federal Law restricts this device to sale by or on the order of a physician or practitioner.
• Accuracy of applanation 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 contact surface of the prism should be checked before each use for damage and
discarded if damage is found.
• We recommend that the prism is not used when it becomes more than two years of age
as, after this time it is possible that body or sterilising fluids may seep inside leading to
possible sterility and cross contamination issues.
• Keeler Applanation Tonometers should be serviced and calibrated annually.Any servicing
or repairs / modifications should only be carried out by Keeler Ltd. or by suitably trained
and authorised distributors. The manufacturer declines any and all responsibility for loss
and / or damages resulting from unauthorised repairs; furthermore, any such actions will
invalidate the warranty.
• Only decontaminate / clean in accordance with a method given in Cleaning (Section 3) of
this instruction manual.
• Use only cloths dampened with water to clean the Applanation Tonometer body. Do not
use corrosive products or alcohol.

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D-KAT Tonometer by KEELER
• Never use the instrument if the ambient temperature, atmospheric pressure, and / or
relative humidity are outside the limits specified in this manual.
• Should the instrument suffer shocks (for example, should it accidentally fall), follow the
check procedure outlined in the ‘Servicing and Calibrations’ (Section 13); if necessary,
return the instrument to the manufacturer for repair.
• Use only the listed accessories in conjunction with the instrument; use said accessories
only in accordance with the procedures set forth in the instruction manuals.
• Always carefully observe the safety rules and other precautions published herein.
• Do not use in the presence of flammable gases / liquids, or in an oxygen rich environment.
• This device is intended to be used only by suitably trained and authorised healthcare
professionals.
• This product should not be immersed in fluid.
• Electrical equipment can be affected by electromagnetic interference. If this occurs whilst
using this equipment, switch the unit off and reposition.
• If during measurement the slit lamp is moved forward toward the patient or the patient
moves toward the slit lamp, the sensor arm will be pushed into contact with a stop spring
and an audible alarm will sound.
CAUTION
• Use only genuine Keeler approved parts and accessories or device safety and performance
may be compromised.
• Keep out of the reach of children.
• To prevent condensation from forming, allow instrument to come to room temperature
before use.
• For indoor use only (protect from moisture).
• There are no user serviceable parts inside. Contact authorised service representative for
further information.
• Follow guidance on cleaning / routine maintenance to prevent personal injury / damage to
equipment.
• Failure to carry out recommended routine maintenance as per the instructions in this IFU
may reduce the operational lifetime of the product.
• At product end of life dispose of in accordance with local environmental guidelines
(WEEE).

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D-KAT Tonometer by KEELER
Batteries
• Do not use a battery that is deformed, leaking, corroded or visually damaged. Handle
a damaged or leaking battery with care. If you come into contact with electrolyte,
wash exposed area with soap and water. If it contacts the eye, seek medical attention
immediately.
• Ensure battery orientation is correct, or personal injury / damage to equipment may occur.
• Do not mix battery types.
• Do not attempt to charge non-rechargeable batteries.
• Dry cell batteries should be removed if your instrument is not to be used for long periods.
• Do not dispose of battery in fire, puncture or short circuit.
• Dispose of batteries in line with local environmental regulations.
• Tape over battery contacts to avoid short circuiting during disposal.
• After removal of the battery do not touch the battery contacts and the patient
simultaneously.
2.2 CONTRAINDICATION
There is no restriction to patient population this device can be used with and there are no
known contraindications associated with the device.
• Do not use contact tonometry on those with ruptured globe, corneal lesions, ulcer or
epithelial defects and patients that are not suitable for anesthesia administration.
• Take extra care with patients with ocular infection to prevent transmission.
3. CLEANING AND DISINFECTION INSTRUCTIONS
3.1 CLEANING TONOMETER BODY
Only manual non-immersion cleaning as described should be used for this instrument. Do not
autoclave or immerse in cleaning fluids. Always disconnect power supply from source before
cleaning.
1. Wipe the external surface with a clean absorbent, non-shedding cloth dampened with
de-ionised water / detergent solution (2% detergent by volume) or water / isopropyl
alcohol solution (70% IPA by volume). Avoid optical surfaces.
2. Ensure that excess solution does not enter the instrument. Use caution to ensure cloth is
not saturated with solution.
3. Surfaces must be carefully hand-dried using a clean non-shedding cloth.
4. Safely dispose of used cleaning materials.

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3.2 DISINFECTING THE TONOMETER PRISMS
Always disinfect the Tonometer prisms before use. Hand hygiene must be
considered to prevent any contamination.
1. Carefully remove the Tonometer prism
from the prism holder. 2. Wash the Tonometer prism under cold running water for approximately 1
minute, to ensure the Tonometer prism
is physically clean before exposed to
the disinfection process.
3. Immerse the Tonometer prism in the
disinfectant fluid. Types of disinfectant
fluid vary.
4. Rinse the disinfectant from the prism
in running water for between 10 and
30 minutes.
10 MINS
10-30
MINS
Please follow disinfectant solution guidelines
for instructions, concentration and time of
immersion. (For example: Pantasept – 3%
aqueous solution for 10 minutes, Hydrogen
Peroxide 3% aqueous solution for 10 minutes,
Sodium Hypochlorite, 10% aqueous solution for
10 minutes etc.).
1 MIN

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D-KAT Tonometer by KEELER
5. Dry the disinfected Tonometer prism
with a clean soft non-shedding cloth. 6. Store the Tonometer prism in a suitable container ready for use.
Safely dispose of the disinfectant fluids used.
Do not disinfect using the following: Alcohol, Acetone, UV radiation,
Sterilisation, Immersion in fluid for more than one hour, Temperatures
greater than 60°C.
4. TONOMETER PRISM FIELD CHECK
Check the Tonometer prism under the Slit lamp and ensure there are no
cracks / chips. The chemical used in the diagnosis process (for example:
Fluorescein) will get into the cracks and will show up if observed under
the slit lamp. Do not use it if there is any sign of cracks / chips.

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5. NAME OF COMPONENTS
1. Power / function button
2. Main body
3. Rotating measurement drum
4. Doubling prism
5. Measurement arm
6. Manufacturers data
7. T type mounting assembly
8. R type mounting assembly
9. Calibration arm socket
10. Battery cover
11. LED display
6. SWITCHING ON / OFF AND CONFIGURING THE D-KAT
6.1 SWITCHING ON / OFF
To switch the D-KAT on, press the function button briefly and the display will show a nominal
reading. The D-KAT can be switched off by pressing the function button again. The unit will
power down when not in use after 3 minutes.
6.2 CHANGING DECIMAL POINT SETTING
Turn on the D-KAT and press the function button for more than 3 seconds.The display will flash
briefly. Release the function button: ‘dP’ (decimal point) or ‘ndP’ (no decimal point) will be
displayed. Press the function button briefly to toggle between both. Once the desired display has
been set release the function button and the D-KAT will return to the pressure readings display.
10
10
11
2
4
4
8
11 6
5
5
1
1
7
3
3
6
29
9
R type D-KAT (fixed)
Part number: 2414-P-2042
T type D-KAT (take-away)
Part number: 2414-P-2032

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D-KAT Tonometer by KEELER
6.3 CHANGING THE VOLUME
Turn on the D-KAT and press the function button for more than 3 seconds. Release the function
button: ‘dP’ (decimal point) or ‘ndP’ (no decimal point) will be displayed.
Press the function button again for more than 3 seconds: the display will flash and once the
function button is released the display will show “V” together with either 0, 1, 2 or 3. Press
the function button briefly to toggle between volumes, 0 for mute to 3 for maximum.
6.4 CHANGING THE DISPLAY BRIGHTNESS
Follow steps as described in 6.3. Once the volume level is displayed, press and hold the function
button for more than 3 seconds. The D-KAT will now show the display light level as “L” together
with 0, 1, 2 or 3. Press the function button briefly to toggle to the desired display brightness.
Note: The D-KAT will return to the main display at any time if the function button is not pressed within the timings
listed above.
6.5 BATTERY STATUS
If “bat” appears in the display when switching on instead of a numerical value, the battery
should be replaced immediately. The battery should be replaced using a 1.5V AA Alkaline type.
7. MEASUREMENT PROCEDURE
7.1 INSTALLATION ON TO THE SLIT LAMP
Before installing the Tonometer on a Slit Lamp ensure that they are
mutually suitable and that the tonometer is level.
Digital Keeler Applanation Tonometer (T type)
1. Position the guide plate in the
Tonometer / test bar support hole on
the Slit Lamp.
2. Lift the Tonometer out of the
packaging and assemble it by inserting
the pin on its base into one of the two
possible openings (for right or left eye)
on the horizontal guide plate above
the slit lamp axis. These positions
are related to the microscope optics
and observation can be made either
through the right or the left eye-piece.
3. The Tonometer will slip easily onto the
support plate; stability is assured by
the locking pins.
4. To obtain an image as clear and
as free of reflexes as possible, the
Guide
plate
T type

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D-KAT Tonometer by KEELER
angle between the illumination and the microscope should be about 60° and the slit
diaphragm should be fully opened.
5. When not in use the Tonometer should be removed from the Slit Lamp and placed
securely back in the packaging or a suitable location.
Digital Keeler Applanation Tonometer ‘Fixed’ (R type)
This instrument is for those who wish the Tonometer to remain permanently on the slit lamp.
1. Mount the plate for the
Tonometer onto the microscope
body using the securing screw.
2. Then mount the Tonometer
mount onto the mounting post.
3. Swing the Tonometer forward
in front of the microscope for
examination. A notch position
ensures exact centring of the
prism with the left objective.
4. To obtain an image as clear
and as free of reflexes as
possible, the angle between
the illumination and the
microscope should be about
60° and the slit diaphragm
should be fully opened.
5. When not in use, the
instrument is swung around
and secured in a notch position
to the right of the microscope.
7.2 PREPARING THE PATIENT
• Use an appropriate topical anaesthetic to numb the cornea.
• Place a strip of fluorescein-soaked paper near the outer canthus in the lower conjunctival
sac. After a few seconds, the lacrimal fluid will be coloured and the paper may be removed.
When using drops, we recommend a 0.5% solution of fluorescein sodium. If using a 1% or
2% solution, use a glass rod to introduce a small quantity of liquid into the conjunctival sac.
• Seat the patient at the Slit Lamp and place his / her chin on the chinrest and ensure the
forehead touches the forehead rest.
• Adjust the chinrest height so that the patient’s eye is at the correct height (most Slit lamps
have a marker on the chinrest pole for correct height adjustment).
Mounting
plate
R type

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D-KAT Tonometer by KEELER
Reusable prisms are not disinfected prior to shipping and must be cleaned
before their first use as described in Section 3 of this document.
Check prisms for damage prior to use.
7.3 PREPARING THE SLIT LAMP INSTRUMENT FOR EXAMINATIONS AT 10X
MAGNIFICATION
• Before beginning measurement, check that
the eyepieces of Slit Lamp are correctly
focused.
• Set the brightness control of the
instrument to a position of a low intensity.
• Set the illumination angle of the Slit Lamp
to be approximately 60° to minimise
unwanted reflections.
• Insert the blue filter on the slit lamp beam
path and fully open the slit diaphragm.
Clean and disinfect prism as described in Section 3 of this document.
• Place the doubling prism on into the holder and align the ‘zero mark’ with the white
alignment line on the prism holder, this ensures the mires have a horizontal split.
• Insert the measurement arm so that the measurement head and microscope optics axes
are convergent.
• Rotate the measurement drum until 10.0 is displayed on the LED.
7.4 USING THE INSTRUMENT / TAKING A MEASUREMENT
Instructions to the patient
• The patient’s head must be firmly positioned on the chin rest and the forehead rest. If
necessary, a band may be used to hold the head still.
• Ask the patient to look straight ahead. If necessary, use a fixation target to keep the eyes still.
• We recommend occasionally reminding the patient during the examination, to keep his /
her eyes wide open. If necessary, the examiner may use the tips of his fingers to hold the
lids open, taking care not to exert pressure on the eye.
• When elevating the lids, the angle between the microscope and the lighting unit must be
reduced to about 10° so that the light beam passes through the body of the prism. In this

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position it should be possible to obtain an image with no reflections.
• Immediately before measurement, ask the patient to close his / her eyes for a few seconds,
in order to ensure that the cornea be sufficiently wetted by the lacrimal fluid containing
the fluorescein solution.
Taking the measurement
• Move the Slit Lamp forward to bring the measuring prism into contact with the centre of
the cornea in the area above the pupil. The limbus will be illuminated with a bluish light.The
examiner will be able to better directly observe this phenomenon from the opposite side.
• As soon as the corneal limbus is correctly illuminated, immediately stop all forward
movement of the Slit Lamp.
• After contact is established, observe the cornea
through the microscope. When the measurement drum
is set to position 10 on the LED, the two semicircular
fluorescein rings (which will vary in size according to
the ocular pressure) will pulse rhythmically when the
Tonometer is in the correct position for measurement.
• Use the Slit Lamp joystick control to make any
corrections needed until the applanated surface is
observed as two semicircular surfaces of equal area
at the centre of the field of vision. (Figure 1). Small
adjustments downward made with the joystick will
have no effect on the sizes of the semicircular images.
• Increase the applanation pressure by rotating the Tonometer measurement drum until the
margins of the fluorescein rings touch and cross as the eye pulses (Figure 2). The width of
the fluorescein rings around the contact position of the measuring prism should be equal
to about 1/10 of the diameter of the applanation surface (0,3 mm).
• The LED reading is the ocular pressure expressed in mmHg.
Figure 1: Semicircular images at the
Centre of the field of vision.
Figure 2: Correct Final Position

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8. PROBLEM SOLVING
8.1 THE FLUORESCEIN RING IS TOO WIDE OR TOO NARROW
Cause:
The fluorescein semicircles are too wide.
The measuring prism was not dried after
cleaning, or the eyelids came into contact
with the measuring prism during
measurement. The pressure reading is higher
than the real intraocular pressure.
Correction:
Move the slit lamp back and dry the
measuring prism with a wad of sterile
cotton wool or lint free cloth.
Cause:
The fluorescein semicircles are too narrow.
The lacrimal fluid has dried during
prolonged measurement. The pressure
reading is lower than real ocular pressure.
Correction:
Move the Slit Lamp back and ask the
patient to close his / her eyes once or twice,
then repeat the measurement procedure.
8.2 THE MEASUREMENT PRISM DOES NOT TOUCH THE CORNEA OR TOO
MUCH FORCE HAS BEEN APPLIED
Cause:
If the patient pulls his / her head back even
slightly, the pulses will become irregular
and the measuring prism contact with the
eye will become intermittent. If the patient
pulls his / her head even further back, the
fluorescein semi-circles will completely
disappear.
Correction:
If possible, use a band to hold the patient’s
head in place.

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D-KAT Tonometer by KEELER
Cause:
If during measurement the slit lamp is moved forward toward the patient or the patient
moves toward the slit lamp, the sensor arm will be pushed into contact with a stop spring
and an audible alarm will sound. The applanation surface will be too large. The image will
not change when the measurement drum is rotated.
Correction:
Retract the slit lamp until regular pulses and a correspondingly smaller applanation surface
are obtained. This is the correct measurement position, in which variations in pressure will
not cause immediate variations in the applanation surface.
8.3 THE TWO SEMICIRCLES ARE NOT CENTRAL IN THE FIELD OF VISION
Correction:
Using the joystick, move the slit lamp up
and to the left.
Cause:
The rings are too far to the right.
Correction:
Using the joystick, move the slit lamp to
the right.
Cause:
The reading in this position is considerably
higher than real ocular pressure.
Correction:
Using the slit lamp height adjustment
mechanism, lower the slit lamp until the two
fluorescein semi circles are equal in size.
The measurement pressure will then be
reduced.