HAAG-STREIT

LENSTAR LS900 Instructions for Use 4th Edition Feb 2011

Instructions for Use

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INSTRUCTIONS FOR USE Biometer

LENSTAR LS 900® 4th Edition / 2011 – 02

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DOK. no. 1500 1500.1400209.04000

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INSTRUCTIONS FOR USE Biometer

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LENSTAR LS 900® 4th Edition / 2011 – 02

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Preface

We would like to thank you for your decision to purchase this HAAG-STREIT product. If the instructions in this manual are carefully followed, we are confident that this product will give you reliable and trouble-free usage.

Purpose of use

The LS 900 is a non-invasive, non-contact OLCR (optical low-coherence reflectometry) biometer used for obtaining ocular measurements and performing calculations to assist in the determination of the appropriate power and type of IOL (intraocular lens) for implantation after removal of the natural crystalline lens. The LS 900 measures: • Axial Eye length • Corneal thickness • Anterior chamber depth • Aqueous depth • Lens thickness • Corneal curvature radii for flat and steep meridian • Axis of the flat meridian • White-to-white distance • Pupil diameter

Caution: Federal law restricts this device to sale by or on the order of a physician or practitioner.

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Contents 1.

1.1 1.2 1.3 1.4 1.5 1.6 1.6.1 1.7 1.7.1 1.7.2 1.7.3 1.8 1.9 1.10 1.11

2.1 2.2 2.3 2.3.1 2.3.2 2.4

Safety

Ambient conditions... 4 Transport and unpacking... 4 Installation warning notices... 4 General points... 5 Plausibility of measurements... 5 IOL calculation... 6 References... 6 IOL constants... 7 IOL constants derived using optical measurements... 7 IOL constants derived using immersion ultrasound measurements... 7 IOL constants derived using contact ultrasound measurements... 7 Optical radiation... 7 Device transportation... 7 Warranty and product liability... 7 Pictographs and type plates... 8

Introduction

Basic construction... 9 Examination components (LS 900)... 9 Control component (PC)... 11 Minimum PC requirements... 11 Minimum monitor requirements... 11 Instrument table... 11

Equipment assembly / installation

Operation

3.1 3.2 3.2.1 3.2.2 3.3 3.3.1 3.3.2 3.3.3 3.4 3.4.1

4.1 4.2

4.3 4.3.1 4.3.2 4.3.3 4.3.4

Measured variables... 18 A-Scan... 18 Keratometry... 19 White-to-white distance... 19 Pupillometry & visual axis... 19

Statutory regulations...20

Software instructions for use...20

Care and maintenance

7.1 7.2

Function check... 20 Cleaning... 21

Classification / safety regulations...21

8.1 8.2 8.3 8.4

EMC... 21 Compliance with standards... 21 RoHS-China... 21 Hazardous Substances or Elements... 21

Environment...21

Additional information...22

Safe system configuration according to IEC/EN60601-1... 12 Instrument table... 13 Mounting the roller rails/slide plate... 13 Mounting the sticker for automatic position recognition... 13 Mounting the device (LS 900)... 14 Lifting the device ... 14 Device connection, cables under the device... 14 Device connection, cables at side (Option)... 16 Computer connection... 17 Software... 17

Position of patient during measurement... 18 Fixation... 18

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1. Safety Symbols

FORBIDDEN! Not observing these notes will lead to equipment damage and endangering of physical damage to patient WARNING! These signs must be adhered to strictly to ensure safe operation of the instrument and to avoid endangering users and patients. NOTE! Important notes! Please read carefully.

1.3 Installation warning notices • Only use a HAAG-STREIT approved external medical power supply (IEC/ EN60601-1, UL60601-1, CAN/CSA C22.2 No 601.1-M90).

-40°C 500 hPa 10%

to to to

+70°C 1060 hPa 95%

Storage:

Temperature Atmospheric pressure Relative humidity

-10°C 700 hPa 10%

to to to

+55°C 1060 hPa 95%

Operating: Temperature Atmospheric pressure Relative humidity

+10°C 800 hPa 30%

to to to

+35°C 1060 hPa 75%

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Before you unpack the instrument, check whether the packing shows traces of improper handling or damage. If this is the case, inform the haulier which has delivered the product to you. Unpack the instrument together with a representative of the haulier. Prepare a protocol describing parts that are possibly damaged. This must be signed by you and by the representative of the haulier. • Leave instrument in the packing for several hours before unpacking (condensation). • After unpacking, check if the instrument has been damaged. • Please carefully retain packing material for reuse in case of return delivery or removal to another location.

• Plug, cable and earth-wire connection on socket must function perfectly. • Make sure that the device is only connected to power sources as defined on

Transport: Temperature Atmospheric pressure Relative humidity

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1.2 Transport and unpacking

Symbols correspond to EN 980 and ISO 15223-1. Other symbols that are used in these instructions:

1.1 Ambient conditions

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the device nameplate. This unit has no ON/OFF switch. Before carrying out maintenance or cleaning work, the device must always be disconnected from the mains by unplugging the DC connector. Computers and other peripherals (printers, etc.) must meet standard IEC/EN 60601-1, or be connected via electrical isolation to external networks (isolating transformer, Ethernet isolator, etc.) For connection to PC, only use the supplied USB cable (2 m).

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1.4 General points NOTES! • The appliance must only be used for the purpose described in these operating instructions for use. • Installation should only be carried out by trained technical personnel. • The device must not be stored or operated outside the prescribed ambient conditions (see section 1.1). • If exposed to the effects of an external force (e.g. by being accidentally knocked or dropped), this type of sensitive measuring device must be promptly checked according to section 7.1 (Function check) and, if necessary, returned to the factory for repair. • Execute function checks when prompted by software (measurement properties, side recognition). • Please keep these instructions for use near the appliance at all times, in a place where it can be accessed easily by operating staff. • Warranty claims will only be considered if the directions in the instructions for use have been followed as specified. • The manufacturer of this device is not liable for loss or damage due to its unauthorized handling. All consequent guarantee claims become invalid. • Never use the device in areas where there is a risk of explosion. Do not store volatile solvents (alcohol, petrol, etc.) or flammable anaesthetics in the vicinity. • Always remove the dust cover before switching on the device. Otherwise, the light sources may be destroyed by overheating. After use, ensure that the device is switched off before replacing the cover. • Repairs should only be undertaken by suitably trained and authorized, technical staff. Improper repairs may result in considerable risk to patient and operator. • Only original spare parts and accessories may be used for repairs. • The software must only be installed by persons trained to do so. • The PC on which the EyeSuite Biometry software is installed must not contain or run any other software that might limit the functioning capabilities of EyeSuite. • Shut down the computer whenever the system is to be out of use for an extended period. © HAAG-STREIT AG, 3098 Koeniz, Switzerland - HS-Doc. no. 1500.7220055.04040 – 4. Edition / 2011 – 02

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WARNINGS! • The Doctor or operator must provide safety instructions that concern him/her and monitor their compliance. • Only suitably-trained and experienced staff must operate the software (for the generation of measuring data and calculations, along with the manual entry, editing and deletion of data) and interpret results. • All members of operating staff must be suitably trained and familiar with the contents of the instructions for use, with particular reference to the safety instructions contained in it. • Measurements can be carried out with dilated or undilated pupils. The A-scan (axial eye length, corneal thickness, anterior chamber depth and lens thickness), keratometry and white-to-white distance measurement are not influenced by dilatation status. Dilatation status does have a bearing on pupillometry.

1.5 Plausibility of measurements • Users should check measurement readings for plausibility. This involves verifying

• • • • • •

the A-scan and the cursor, which is automatically adjusted with respect to signal peaks, whenever the LS 900 displays an abnormally high standard deviation for axial eye length, corneal thickness, anterior chamber depth and/or lens thickness. The operator should also take into account the type (e.g. posterior subcapsular cataract) and density of the cataract when evaluating plausibility. Measurement readings obtained from patients with a non-intact cornea (e.g. due to a corneal transplant, corneal opacity or corneal scarring) may possibly be inaccurate (this applies to keratometry in particular), and the user should check the data for plausibility. We recommended carrying out of five measurements on each eye. The user should ensure, before carrying out the measurement procedure, that the patient is not wearing contact lenses, as their presence is likely to give rise to incorrect measurement readings. It may not be possible, under certain circumstances, to carry out measurements on persons with fixation problems. Dense lenticular opacities may make it impossible to measure the axial eye length and lens thickness. Pronounced opacities of the central cornea can likewise make it impossible to measure corneal thickness, anterior chamber depth, lens thickness or axial eye length.

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• Blood in the vitreous may make it impossible to measure the axial eye length. • Keratometry may be erroneous in eyes that underwent keratorefractive surgery because such eyes may significantly deviate from spherical surfaces.

• The user should make a visual check, when carrying out the measurement procedure, to ensure that all light spots are present.

• If the appliance repeatedly generates error messages, stop using it and contact the customer service.

• You are recommended always to examine both the patient’s eyes. The user

•

• • • • •

should subject the measurement readings to extra scrutiny if there is a notable difference between the right and left eye. The following are classed as notable differences: • More than 1 D with respect to central corneal refractive power => 0.18 mm difference with respect to the corneal curvature radius • More than 0.3 mm with respect to axial eye length • More than 1 D with respect to emmetropic IOL refractive power The user should check the A-scan when measuring anterior chamber depth in pseudophakic mode. If only one IOL signal is visible, it is not clear whether this signal relates to the front or back of the IOL. Uncertainty in this case can lead to the displayed reading for anterior chamber depth being inaccurate by the thickness of the IOL (approx. +/-1 mm). An excessively tilted or decentered IOL may make it impossible to measure the anterior chamber depth and aqueous depth in pseudophakic eyes. An intraocular pressure reading corrected on the basis of the measured corneal thickness does not in itself constitute a reliable diagnosis of glaucoma. Ambient light has a bearing on pupil-diameter measurement readings. The user is responsible for ensuring the correct level of ambient light when carrying out pupillometry. The LS 900 cannot monitor ambient light, so do not use pupillometry as the decisive factor when considering keratorefractive surgery. The white-to-white distance reading is merely an indirect measurement of the inner lateral dimensions of the anterior ocular section. It therefore provides only approximate indications of the actual inner lateral dimensions of the anterior ocular section and of the size of the implant used. The measured results of patients with asteroid hyalosis may not be accurate (in particular the axial length measurement) and must therefore be verified by the user in terms of their plausibility.

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1.6 IOL calculation

The measurements taken with the LS 900 are one central element of every IOL calculation. The other important part is the IOL constant used to calculate the power of an IOL to be implanted. Using the LS 900, an optical non-contact biometer, constants optimised for optical biometry should be used. Please contact the respective IOL Manufacturer to get information on optimised IOL constants for an individual set of lenses used. An alternative source for IOL constants optimised for optical biometry is the homepage of the “User Group for Laser Interference Biometry” (ULIB) of the University of Wuerzburg, Germany. Even though the constants published there have been optimised for a different optical biometer than the LS 900, recently published, peer reviewed studies [1, 2, 3] indicate that ULIB published data can be used to calculate IOL power in connection with the LS 900. To further improve the outcome of the IOL calculation, it is recommended that every surgeon creates personalised IOL constants based on preoperative data generated with the LS 900 and data from a stable refraction analysis at least 3 months post-operative.

1.6.1 References

[1] P J Buckhurst, J S Wolffsohn, S Shah, S A Naroo, L N Davies, E J Berrow, “A new optical low coherence reflectometry device for ocular biometry in cataract patients”, British Journal of Ophthalmology 2009;93:949-953 [2] M P Holzer, M Mamusa, G U Auffarth, „Accuracy of a new partial coherence interferometry analyser for biometric measurements”, British Journal of Ophthalmology 2009;93: 807-810 [3] K Rohrer, B E Frueh, R Wälti, I A Clemetson, C Tappeiner, D Goldblum, “Comparison and Evaluation of Ocular Biometry Using a New Noncontact Optical Low-Coherence Reflectometer”, Ophthalmology 2009, 116:2087-2092

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1.7 IOL constants

It is recommended to use personalised IOL constants to achieve maximum prediction accuracy of the IOL calculation. Using personalised IOL constants minimises the effects of individual surgical techniques, individual measurement and surgical equipment, ocular dimensions and ethnic specialities of a patient population on the IOL calculation.

1.7.1 IOL constants derived using optical measurements

If there are optimised or even personalised IOL constants available from a different optical biometer than the LS 900, they may be used as well with the LS 900 to achieve clinically identical results [1, 2, 3]. Optimised constants for optical biometers can also be found on the web site of the “User Group for Laser Interference Biometry” (ULIB) of the University of Wuerzburg, Germany.

1.7.3 IOL constants derived using contact ultrasound measurements

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1.8 Optical radiation

According to IEC 60825-1, the limiting values for class 1 lasers are respected when the device is used in the defined manner.

1.9 Device transportation

Use original packaging when transporting the device over long distances. For short distances, grasp the lower part of the device with both hands and lift (see section 3.3.1).

1.10 Warranty and product liability • This product left our factory in perfect order. Please contact your dealer if you have any complaints.

• The manufacturer grants a warranty on the instrument. For information regarding

1.7.2 IOL constants derived using immersion ultrasound measurements

If there are optimised IOL constants available for immersion ultrasound, they may be used as a starting point for IOL calculation with the LS 900. Differences in IOL calculation may still occur due to differences in the keratometry measurements of the LS 900 and the keratometer used in combination with the immersion ultrasound. A comprehensive manual how to convert existing ultrasound biometry optimised IOL constants to optical biometry optimised IOL constants can be found on the web site of the “User Group for Laser Interference Biometry” (ULIB) of the University of Wuerzburg, Germany. Still such converted data should only be used as a starting point to derive personalised constants.

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warranty conditions, please refer to your local HAAG-STREIT representative. The manufacturer warranty covers breakdowns and defects that are caused by materials and design. Breakdowns and defects that are caused by improper use or outside influences are excluded from the warranty. Any attempt to carry out unauthorized repairs will immediately void all warranty liability. Personal injury may result if the PC on which the EyeSuite biometry software is installed contains or runs other software that is likely to limit the functioning capabilities of EyeSuite. The manufacturer will accept no liability whatsoever in such cases. Continued use of a product that has been damaged by incorrect operation can lead to personal injury. The manufacturer will accept no liability whatsoever in such cases. Failure to follow the directions in the instructions for use will void all warranty claims.

If there are optimised constants available for a contact ultrasound biometer in combination with a keratometer, respective IOL constants have to be converted into constants optimised for optical biometry. A comprehensive manual how to convert existing ultrasound biometry optimised IOL constants to optical biometry optimised IOL constants can be found on the web site of the “User Group for Laser Interference Biometry” (ULIB) of the University of Wuerzburg, Germany. Still such converted data should only be used as a starting point to derive personalised constants. © HAAG-STREIT AG, 3098 Koeniz, Switzerland - HS-Doc. no. 1500.7220055.04040 – 4. Edition / 2011 – 02

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1.11 Pictographs and type plate a) DC Power b) HS-Part number c) Type B equipment d) Date of manufacture e) Manufacturer f) Serial number g) Read User Guide carefully h) Disposal remark i) Pull out mains connector!

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1250

Product: Biometer Type: LS 900 Input:

12V

±5%, 1A

1123 1020338 01020

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REF XXXXXXX

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XXXX HAAG-STREIT AG Gartenstadtstrasse 10 3098 Koeniz, Switzerland

SN XXXXX

Made in Switzerland Caution: Federal law restricts this device to sale by or on the order of a Physician or Practitioner

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2. Introduction

2.1 Basic construction

The system is divided into two parts: one concerned with examination (LS 900) and the other with control (Notebook, PC). The examination part communicates via a USB connection with the external PC. The LS 900 is operated through software installed on the PC. Integral, automatic error recognition for measurements guarantees reliable examination results. The latest biometrics software can be downloaded or updated from internet via the homepage.

2.2 Examination components (LS 900)

Overview 1. Front ring 2. Housing 3. Service cover 4. Cable cover 5. Joystick 6. Cross slide 7. Side identification sticker 8. Headrest 9. Forehead band 10. Auxiliary marking optimal eye height 11. Chin rest 12. Chin rest height adjustment 13. Hand grips for patient

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2 3

5 6 7

Device state The device state indicator allows device monitoring without PC software: 14. State indicator

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Joystick The joystick is used to position the device in relation to the patient’s eye. 15. Trigger Connections 16. USB – device connection 17. DC – device connection 18. USB 2.0 cable 19. DC cable 20. Cable tension compensator

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2.3 Control component (PC)

A commercial PC is used as the control component for the biometer. Control software runs under Windows XP, Windows Vista and Windows 7.

2.3.1 Minimum PC requirements • Intel Core 2 Duo 2.0GHz • RAM: 2GB (XP), 4GB (VISTA / 7) • 160MB Harddisk • CD-ROM / DVD • USB 2.0 connection (ICH5) 2.3.2 Minimum monitor requirements • 1280x800 pixel 2.4 Instrument table

An adjustable instrument table (option) allows the height of the device to be set comfortably to the height of the individual patient. 21. Table top 22. Left-hand drawer (for external medical power supply) / Switch box SB01 23. Right-hand drawer (empty) 24. Elevator column (mechanical with spring) 25. Pedestal with castors

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3. Equipment assembly / installation

3.1 Safe system configuration according to IEC/EN60601-1 WARNING! All externally connected devices must meet the relevant safety standards. 26. Power supply (LS 900) 27. Instrument Table 28. Isolation Transformer 29. Laptop / PC 30. Power supply (PC) 31. Printer

LAN

med. approved IEC/EN60601-1

200

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3.2 Instrument table

The instrument table is delivered in a separate package. To assemble the table, please consult the instructions for use enclosed with it.

med. approved IEC/EN60601-1

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3.2.1 Mounting the roller rails/slide plate

The roller rails/slide plate must be positioned in such a way that, when the device is centered, the patient’s eye will be at a distance of 68mm from the front of the device. 32. Rail 33. Side identification sticker 34. Gliding plate 35. Headrest columns 36. Aperture for cables

3.2.2 Mounting the sticker for automatic position recognition • Take off rail cover and move the device to the side, if already in position. • Clean surface of table. • Remove protective film (Figure 37) from back of the sticker. Start lifting it off carefully from the corner opposite the white area.

• Position the sticker with the white side against the right roller rail (38) and the •

edge of the table (Figure 39). Press the black/white area down firmly and stroke out any air bubbles. Carefully tear off the rest of the sticker (Positioning Tool) along the perforations (Figure 40).

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3.3 Mounting the device (LS 900) 3.3.1 Lifting the device

To lift or reposition the device (short distances only): a) Grasp device from behind with one hand on the column and lift (Figure 41). b) With the second hand, support under the cross-slide (Figure 42).

3.3.2 Device connection, cables under the device

The device can be invisibly wired by passing cables through the cross-slide and using the cable channel underneath. To do this, you need either the HAAG-STREIT instrument table HSM901 with table-top biometer, or an aperture in the table-top used. • Remove cable cover (Figure 43). • Expose USB and supply cables (table aperture, Figure 44). • Push supply cable through aperture in base of cross-slide until the cable emerges from the upper front aperture (Figure 45). • Push USB cable through the same aperture in the cross-slide (Figure 45). • Plug both cables into the corresponding boxes and fix with the tension compensator (Figure 46). • Replace cable cover (Figure 47).

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3.3.3 Device connection, cables at side (Option) • Remove cable cover (Figure 48). • Expose USB and supply cables (left or right aperture on rail cover). • With a knife, cut towards the snap-off point provided on the left or right of the cable cover (Figure 49).

• Carefully use fingers to snap off the cut part (Figure 50). • Insert both cables in the appropriate box and fix with the tension compensator. • Join both cables together with a spiral wrap and attach firmly using the cable

channel on the rail cover (Figure 51).

• Replace cable cover

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3.4 Computer connection • Connect the LS 900 to the PC with the enclosed USB 2.0 cable. Use of the 2 m cable supplied with delivery is recommended.

WARNING! The USB cable should not exceed 5 m in length, otherwise impairment of device function must be expected. 50

• Insert mains cable. Integral mains components work with the voltages specified •

under section A.1.2 'Electrical data'. It is not necessary to select the voltage on the device. If an instrument table has been supplied, the power supply of the LS 900 can be connected to the Switchbox SB01 (left drawer). Use the manual enclosed with the switchbox and the instrument table.

3.4.1 Software WARNING! The software must only be installed by trained persons according to the separate software installation manual.

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4. Operation

4.1 Position of patient during measurement

The positioning of the device is done manually by the user. The patient must be positioned in such a way that the distance from the measuring head to the eye is approx. 68 mm (Figure 52). A steady head position is promoted by resting the patient’s head well against the chin rest and forehead band, and by the patient holding on to the handles supplied. This can positively influence adjustment time and measuring accuracy.

4.2 Fixation

To obtain usable results, the patient must stare at the red fixation light in the measuring lens during measurement. If the patient has difficulty seeing the fixation light with the eye being measured, this can be remedied by fixing the other eye on an opposed remote object.

4.3 Measured variables 4.3.1 A-Scan

Depending on the patient’s gaze at the fixation light, the optical path length of the visual axis is measured (Figure 53). CT: Corneal thickness AD: Aqueous depth (back of cornea to front of lens). LT: Lens thickness AL: Eye length (front of cornea to the inner limiting membrane).

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INDICATION! Since the device measures up to the retinal pigmented epithelium, the reading displayed is adjusted to the internal limiting membrane either automatically, in an axial length dependent manner or manually. (Manual correction not available in the USA).

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4.3.2 Keratometry

Keratometry is calculated through the position of 32 projected light reflections. Sixteen measuring points on each eye are arranged in two rings with the following diameters (standard eye R = 7.8 mm): Outer measuring points: 2.3 mm Inner measuring points: 1.65 mm For each measuring point, the equivalent of an ideal sphere is calculated. The values displayed (flat radius, steep radius) correspond to the radii of an ellipsoid that fits into the assemblage of points. The axis of its rotation is measured counterclockwise from the horizontal to the flat radius (Figure 54). e: Flat radius f: Steep radius g: Axis of its rotation

4.3.3 White-to-white distance

The white-to-white distance (WTW) is determined using the image of the iris and the eye radii obtained from keratometry. The value displayed corresponds to the diameter of an ideal circle (Figure 55).

4.3.4 Pupillometry & visual axis

Pupil diameter (Ø) corresponds to the diameter of an ideal circle, with the smallest error square to the established pupil border. At the same time, the shift of visual axis towards the centre of the pupil is provided. The calculated dimensions are located on the theoretically derived level of the iris. Image enlargement achieved by breaking up the eye is disregarded (Figure 56).

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• HAAG-STREIT AG uses a quality management system according to EN ISO

The LS 900 is practically maintenance free and only requires minimal care to provide complete satisfaction over a long working life. However, we recommend instructing a service engineer to inspect the biometer periodically. HAAG-STREIT or your local agent will be happy to provide further information.

•

7.1 Function check

5. Statutory regulations

• • •

13485:2003. The LS 900 has been designed and manufactured in compliance with IEC / EN 60601-1, IEC / EN 60601-1-2, IEC 60825-1, EN ISO 15004-1 and EN ISO 10343. CE designation certifies the conformity of the LS 900 with European Directive 93/42 EEC (conformity module H). The LS 900 is a class IIa device under the terms of this directive. The LS 900 conforms to European Directive 2002/95/EC (RoHS). HAAG-STREIT can supply a copy of the European Declaration of Conformity for this product on request at any time. The statutory accident prevention regulations must be observed.

6. Software instructions for use

The inspection gauge (Figure 57) supplied with the device will assist the user in checking the proper functioning of the unit. This check takes place for the first time when the device is commissioned. Subsequent test intervals (1 week) will be specified by the software (message displayed). For exact procedure see software instructions for use. Should the test be out of the tolerance limits, a software message appears and the unit has to be set out of operation. Notify your HAAG-STREIT customer support center.

Device operation for carrying out an examination is set out in the separate instructions for use, together with a description of EyeSuite application software.

7. Care and maintenance WARNING! • Biometer housing parts should only be removed by trained personnel. • Before removing housing parts, the device must always be disconnected from mains power by unplugging the mains power cable. • Repairs should only be undertaken by suitably trained and authorized, technical staff. Improper repairs may result in considerable risks to patient and operator. • If parts must be replaced, only original spare parts supplied by HAAG-STREIT or its agent should be used. • Warraty claims cannot be enforced if the directions in the instructions for use have been ignored.

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