Keeler KAT R, Instructions For Use Manual

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3
EN
KAT R Type and T Type Tonometer by KEELER
1. INDICATIONS FOR USE
These devices are intended to be used only by suitably trained and authorised healthcare
professionals.
The KAT should be used only by trained personnel. USA Federal law
restricts this device to sale by or order of a physician.
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 Applanation Tonometer is indicated for measuring intraocular pressure to aid in the
screening and diagnosis of glaucoma.
The Keeler Applanation Tonometer (KAT) is an accessory item for most ‘Tower Illumination’ type
of Slit Lamps and thanks to its versatility, the 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 6.5 on page 11 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.
• 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 mm
3
) increases intraocular pressure by only about 2.5%.