Operators Manual
138 Pages
Preview
Page 1
NIDEK CO., LTD. (Manufacturer)
: 34-14, Maehama, Hiroishi-cho, Gamagori, Aichi 443-0038, Japan Telephone: (81-533) 67-6611 Facsimile: (81-533) 67-6610 NIDEK CO., LTD : 3F Sumitomo Fudosan Hongo Bldg., 3-22-5, Hongo, (Tokyo Office) Bunkyo-Ku, Tokyo 113-0033, Japan Telephone: (81-3) 5844-2641 Facsimile: (81-3) 5844-2642 NIDEK INCORPORATED : 47651 Westinghouse Drive, Fremont, California 94539, U. S. A. (United States Agent) Telephone: (510) 226-5700 Facsimile: (510) 226-5750 NIDEK SOCIETE ANONYME : Europarc 13, rue Auguste Perret, 94042 CRETEIL, France (Authorized Representative) Telephone: (01) 49 80 97 97 Facsimile: (01) 49 80 32 08
March 2009 14900-P902I Printed in JAPAN
BEFORE USE OR MAINTENANCE, READ THIS MANUAL. THIS MANUAL CONTAINS INFORMATION NECESSARY FOR THE OPERATION AND MAINTENANCE OF THIS INSTRUMENT, US-1800. This Operator's Manual contains information for the operation of the ultrasonic axial length/ corneal thickness measurement device, ECHOSCAN US-1800. This manual provides a general outline, cautions for safety, operating procedures, specifications, description of accessories, and maintenance instructions for the US-1800. IEC and EN standards are applied to the device described in this manual. This manual is necessary to understand the correct use of this device. Cautions for safety and operating procedures must be thoroughly understood before use. Be sure to keep this manual with the device and refer to it when necessary. The purpose of the US-1800 is to measure axial length/corneal thickness and calculate IOL power. Physicians should operate the device as described in this manual and are responsible for the selection of treatment for determining the application of the US-1800. If you find any problems during or have any questions about operation, please contact NIDEK or your authorized distributor.
Table of Contents
§1
Page INTRODUCTION ... 1-1 1.1 Outline ... 1-1 1.2 Indications for Use ... 1-2 1.3 Principle ... 1-2 1.4 Classifications ... 1-3 1.5 Symbol Information ... 1-4
§2 SAFETY ... 2-1 2.1 Cautions in Use ... 2-1 2.1.1 General cautions ... 2-1 2.1.2 Probe ... 2-2 2.2 Storage Precautions ... 2-3 2.3 Transport Precautions ... 2-3 2.4 Installation Precautions ... 2-4 2.5 Wiring and Connection Precautions ... 2-5 2.6 After Use ... 2-6 2.7 Maintenance and Check ... 2-6 2.8 Disposal ... 2-7 2.9 Labels ... 2-8
§3 DEVICE DESCRIPTION ... 3-1 3.1 Exterior Features ... 3-1 3.2 Accessories ... 3-5 3.3 Operation Screens ... 3-6 3.3.1 Axial length measurement screen ... 3-6 3.3.1.1 Data saving window ... 3-11 3.3.2 IOL calculation screen ... 3-13 3.3.2.1 IOL list window ... 3-16 3.3.2.2 IOL comparison screen ... 3-17 3.3.3 Data filing screen ... 3-18 3.3.3.1 Measured data reading window ... 3-22 3.3.4 Corneal thickness measurement screen ... 3-24 3.3.4.1 Map edit screen ... 3-28 3.3.5 Patient’s data input window ... 3-30 3.3.6 Physician setting screen ... 3-32 3.3.6.1 Personal value calculation screen ... 3-35 3.3.6.2 IOL registry screen ... 3-37 3.3.6.3 IOL formula registry screen ... 3-39 3.3.6.4 Date and time setting screen ... 3-41 3.3.7 Input window ... 3-42
Page 3.3.7.1 Key board window ... 3-42 3.3.7.2 Numeric key window ... 3-43
§4 OPERATING PROCEDURES... 4-1 4.1 Operation Flow ... 4-1 4.2 Setup ... 4-3 4.2.1 Location of installation ... 4-3 4.2.2 Connection of each part ... 4-3 4.3 Preparation ... 4-6 4.4 Operation ... 4-8 4.4.1 Axial length measurement ... 4-8 4.4.1.1 Basic operation of the axial length measurement... 4-8 4.4.1.2 Cautions in the axial length measurement ... 4-12 4.4.1.3 Manual gate ... 4-14 4.4.1.4 Saving measured data ... 4-16 4.4.2 Calculation of IOL refractive power ... 4-18 4.4.3 Comparison of saved data ... 4-22 4.4.4 Corneal thickness measurement ... 4-25 4.4.4.1 Basic operation of the corneal thickness measurement ... 4-25 4.4.4.2 Map edit ... 4-28 4.4.5 Inputting patient’s data ... 4-30 4.4.6 Setting each physician’s data ... 4-32 4.4.6.1 Calculation of personal values ... 4-35 4.4.6.2 Registering IOL data ... 4-37 4.4.6.3 Registering IOL formulas ... 4-39 4.4.6.4 Setting the date and time ... 4-41 4.4.7 Operation method of the foot switch ... 4-43 4.4.7.1 In axial length measurement ... 4-43 4.4.7.2 In corneal thickness measurement ... 4-43 4.5 Print Forms ... 4-43 4.5.1 In axial length measurement ... 4-43 4.5.2 In IOL calculation ... 4-47 4.5.3 In corneal thickness measurement ... 4-49 4.6 Completion of Operation ... 4-50
§5 MAINTENANCE ... 5-1 5.1 List of Consumables and Maintenance Parts ... 5-1 5.2 Replacement of Printer Paper ... 5-1 5.3 Replacement of Fuses... 5-2 5.4 Cleaning ... 5-3
Page 5.4.1 Cleaning the exterior ... 5-3 5.4.2 Cleaning the touch screen ... 5-4
§6 CHECK ... 6-1 6.1 Checks Before Use ... 6-1 6.2 Usage of the Test Piece ... 6-2 6.2.1 Usage of the test piece for axial length measurement ... 6-2 6.2.2 Usage of the test piece for corneal thickness measurement ... 6-3 6.3 Check List ... 6-4
§7 TROUBLE SHOOTING ... 7-1 §8 IOL FORMULAS ... 8-1 8.1 Outline of IOL Formulas ... 8-1 8.2 SRK Formula... 8-1 8.3 SRK-II Formula ... 8-2 8.4 SRK-T Formula ... 8-4 8.5 BINKHORST Formula ... 8-5 8.6 HOFFER-Q Formula ... 8-6 8.7 HOLLADAY Formula ... 8-7
§9 SPECIFICATIONS ... 9-1 9.1 Measurement Functions ... 9-1 9.1.1 Axial length measurement/IOL calculation ... 9-1 9.1.2 Corneal thickness measurement ... 9-2 9.2 Display/Printer... 9-2 9.3 Power Supply and Others ... 9-3 9.4 Acoustic Field Emissions ... 9-4
§10ACCESSORIES ... 10-1 10.1 Standard Accessories ... 10-1 10.2 Optional Accessories ... 10-1
§11EMC (ELECTROMAGNETIC COMPATIBILITY) ... 11-1
§1 INTRODUCTION 1.1 Outline The NIDEK Echoscan Model US-1800 is an ultrasonic device to measure axial length and corneal thickness applying the ultrasonic pulse reflection method. Axial length is one of the parameters used to determine the refractive power of an IOL prior to cataract surgery. By inputting the measured axial length with other parameters, the refractive power of an IOL can be calculated. Corneal thickness is a necessary parameter when considering the clinical influence of surgery, drugs and contact lenses upon endothelium tissue. In recent years, corneal thickness measurement is performed prior and posterior to corneal refractive surgery using devices such as the excimer laser. The US-1800 is comprised of a main body with a touch screen and built-in printer, a probe and test piece for axial length measurement, and a foot switch. In addition, a probe and test piece for corneal thickness measurement are available as optional accessories.
1.2 Indications for Use The NIDEK Echoscan Model US-1800 is used for measuring the axial length and corneal thickness of the eye. The measured axial length value is used to calculate the IOL power along with other parameters prior to the cataract extraction surgery. Corneal thickness is one of the major parameters for the corneal refractive surgery such as Radial Keratectomy (RK) or LASIK. The corneal thickness is also an index for diagnosing the corneal edema, which is caused by the damaged corneal endothelial function.
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1.3 Principle Ultrasonic waves are the sound waves pitched above the range of human hearing whose frequency is 20,000Hz or more. In the medical field, ultrasonic waves whose frequencies are between 1 and 15MHz are applied, and these types of high sound waves have the following characteristics similar to light: They have a high tendency to travel straight. They have characteristics such as reflection and refraction at the boundaries of media which have different acoustic impedances. (Acoustic impedance = Density of medium × Sonic velocity in the medium) Special material is adopted to transmit and receive the ultrasonic pulses. Electrodes are placed on both sides of a thin piece of material, and the thickness of the material is changed by the fluctuation of voltage when a voltage is applied between them. The material vibrates with its inherent frequency when voltage is applied, and transmits the ultrasonic pulses. Conversely, when this material vibrates by receiving the ultrasonic pulses, voltage of the same frequency is generated on both electrodes and it becomes possible to receive the ultrasonic pulses as electrical signals. This phenomena is called the “Piezo effect”, and the converter, which electrically generates the ultrasound waves and changes them into voltage, is called a transducer. In axial length measurement, the ultrasonic pulse travels inside the eye when the probe is put on the eyeball. A part of the pulses is reflected from the boundary of the cornea, anterior chamber, lens, vitreous body and retina, and their echoes are received at the same probe. The received echoes are converted to the electronic acoustic signals and indicated on the LCD as an amplitude. In addition, the time difference of each echo is measured and the size of each area of tissue (anterior chamber depth, lens thickness, vitreous body length and axial length) is calculated according to the time difference and known inherent sonic velocity through each kind of tissue. As for corneal thickness measurement, the ultrasonic pulses are transmitted when the probe is put on the cornea. A part of the pulses is reflected at the front and rear surface of the cornea. When the probe receives the reflected echoes, the time difference of each echo is measured and the corneal thickness is calculated according to the time difference and known inherent sonic velocity through the cornea. When the directions of the ultrasonic waves are not perpendicular to each boundary surface in both axial length and corneal thickness measurements, however, the echo is rather weak or does not return to the probe. For such reason, it is very important to coincide the direction of the ultrasonic wave with the visual axis in order to achieve the correct measurement.
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1.4 Classifications Classification under the provision of 93/42/EEC (MDD) Class US-1800 is classified as a Class a device.
a
Protection method against electric shock Class I US-1800 is classified as a Class I device. A Class I system provides protection against electric shock and does not rely on basic insulation only, but which includes additional safety grounding of accessible conductive parts in the fixed wiring in such a way that accessible conductive parts cannot become live in the event of a failure of the basic insulation. Degree of protection against electric shock: Type B applied part US-1800 is classified as a device with a Type B applied part. A device with a Type-B applied part contains an internal electrical power source providing an adequate degree of protection against electric shock in regards to: - allowable leakage currents - reliability of the protective ground connection (if present). Degree of protection against ingress of liquids: IP20 US-1800 is classified as an ordinary device. An IP-20 device has an enclosure which protects against the intrusion of solid objects whose diameter is 12.5mm or more such as fingers. However, it is an ordinary unit without protection against an ingress of liquids. Do not expose water to the device. Methods of disinfection recommended by manufacturer Disinfect the probe tip of the US-1800 following the method described below. - After immersing the probe tip in 0.1% Chlorhexdine gluconate solution or ethanol for disinfection for 10 minutes, wipe it with gauze dampened with ethanol a few times. Then dry it. Degree of safety application in the presence of flammable anesthetics and/or flammable cleaning agents US-1800 should be used in an environment where no flammable anesthetics and/or flammable cleaning agents are present. Mode of operation US-1800 is classified as a continuous operating device. Classification by transference US-1800 is classified as a transportable device.
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1.5 Symbol Information This symbol identifies the ON power switch setting. When the switch is set in this symbol position, power is supplied to the device. This symbol identifies the OFF power switch setting. When the switch is set in this symbol position, power is not supplied to the device. This symbol identifies the fuse rating. This indicates that the degree of protection against electrical shock of the applied part is classified as a Type B applied part. This symbol identifies that the power source to be supplied to the device must use alternating current. This symbol warns that reference to the operator’s manual is necessary for safe operation of the device. This symbol indicates that the foot pedal is to be connected to this port. This symbol indicates that the external fixation lamp is to be connected to this port. Indicates that this product shall be disposed of in a separate collection of electrical and electronic equipment in EU.
§2 SAFETY In this manual, a Signal Word is used to designate the degree or level of safety alerting. The definition is as follows: CAUTION: Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury or equipment damage.
To avoid damage to personnel and the device, follow all the instructions mentioned below when using the device.
2.1 Cautions in Use 2.1.1 General cautions CAUTION • Never use this device for purposes other than axial length measurement, IOL refractive power calculation or corneal thickness measurement. If any accident occurs, NIDEK assumes no responsibility. • If any trouble occurs, do not touch anything inside of the device. Unplug the power cord from the power outlet and contact NIDEK or your authorized distributor. • Do not modify or touch the interior of the device. To do so may cause an electric shock or malfunction. • Be sure to use a wall outlet with a protective ground which meets the power requirements. If the power voltage is too high or too low, the device will not deliver full performance, or a malfunction or fire may occur. • Always hold the plug, NOT the cord, when plugging or unplugging the power cord to or from the power outlet. The power cord may break and it may become overheated. • Be sure not to rest any heavy objects on the power cord. Power may not be supplied due to a break in the cord, and there is a fear that a short circuit or an electric shock may occur because of the damage to the sheath.
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CAUTION • If the core of the power cord is exposed, immediately replace it with an undamaged one. Failure to do so may cause an electric shock or a fire. • Always hold the plug, NOT the cable, when connecting or disconnecting the foot switch cable in order to prevent a breakage. • Do not contact the touch screen with anything other than fingers during operation. Be sure not to press two or more positions on the touch screen at the same time. If a solid or sharp object (such as ball-point pen) touches it, the touch screen may be damaged. Moreover, a malfunction may occur when two or more positions are pressed at the same time. • Do not expose the touch screen to direct sunlight or ultraviolet rays during operation. The touch screen may be damaged.
2.1.2 Probe CAUTION • Always hold the plug, NOT the cable, when connecting or disconnecting the probe. If the cable breaks near the probe side, it is necessary to replace the whole probe. • Disinfect the probe tip for every patient. Failure to do so may cause infection of patient’s cornea. • Before measurement, verify that there are no scratches or chips on the surface of the probe tip which contacts the cornea. If there are, the cornea may be damaged. • Pay attention not to bump the probe tip during operation. The probe tip may be deformed or chipped. • Do not press the probe against the patient’s cornea with excessive force. The measurement result becomes unstable and the patient’s eye may be damaged. • Never perform autoclaving or EOG sterilization to either the probe for axial length measurement or the probe for corneal thickness measurement. The probes may be damaged.
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2.2 Storage Precautions CAUTION • Store the device in a location: - out of direct sunlight. - not exposed to water. - not exposed to chemical agents. - where there is no salt, sulfur, toxic gas or large amounts of dust in the air. - where the specified temperature and humidity requirements for storage are met. - where no vibration or shock may occur and there is no slanting.
2.3 Transport Precautions CAUTION • Disconnect the probe and foot switch from the main body when transporting. Put the cap on the probe tip and then store it in the special case. • Hold the device with both hands when transporting. If the device is held by one hand, there is a fear of it dropping and becoming damaged. • Never pull the power cord. Never drag the power cord by transporting the device with the power cord connected to the body. Injury, or malfunction of or damage to the cord may result. • When transporting the device, pack it in the packing material supplied at the time of purchase.
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2.4 Installation Precautions CAUTION • Install the device in a level and stable place that is vibration-free and shock-free. The device may fall or malfunction. • Avoid installing the device in a place where it is exposed to direct sunlight or ultraviolet rays. The device may malfunction. • Avoid installing the device in a place where it is exposed to water. If water gets into the device, you may get an electric shock and the device may malfunction. • Avoid installing the device in a place where there is salt, sulfur or large amounts of dust in the air. The device may not work normally or may malfunction. • Install the device in an environment where the specified temperature and humidity requirements are met. The device may not work normally or have troubles. • Check that the line voltage is proper before plugging the power cord into the wall outlet. The proper voltage is shown on the rating plate. If the line voltage is too low or too high, the device cannot deliver full performance and will be damaged. • Install the device so that the air vent on the cover of the main body is not blocked. • This device has been tested and found to comply with the limits for medical devices to the IEC60601-1-2:2001 and Medical Device Directive 93/42/EEC. These limits are designed to provide reasonable protection against harmful interference in a typical medical installation. This device generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to other devices in the vicinity. However, there is no guarantee that interference will not occur in particular installation. If this device does cause harmful interference to other devices which can be determined by turning the device off and on, the user is encouraged to try to correct the interference by one or more of the following measures; - Reorient or relocate the receiving device. - Increase the separation between the device. - Connect the device into an outlet on a circuit different from that to which the other device(s) are connected. - Consult the manufacturer or field service technician for help.
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CAUTION • When this device is used together with other equipment, the equipment shall be certified according to Standard IEC60601-1. If this device is used together with equipment which is not certified according to Standard IEC60601-1, you may get an electric shock and the device may malfunction. • In installation and operation of the device, observe the following instructions about EMC (electromagneticcompatibility): - Do not use the device simultaneously with other electronic equipment to avoid electromagnetic interference with the operation of the device. - Do not use the device near, on, or under other electronic equipment to avoid electromagnetic interference with the operation of the device. - Do not use the device in the same room with other equipment such as life-support equipment, other equipment that has major affects on the life of the patient and results of treatment, or other measurement or treatment equipment that involves small electric current. - Do not use the device simultaneously with portable and mobile radio frequency communication systems because it may have an adverse effect on operation of the device. - Do not use cables and accessories that are not specified for the device because that may increase the emission of electromagnetic waves from the device or the system and decrease the immunity of the device to electromagnetic disturbance. • The International Electrotechnical Commission sets the essential requirements for electrical and electronic equipment that may disturb, or be disturbed by, other equipment. The US-1800 complies with these requirements as tabled on pages 11-1 to 11-3. Follow the guidance in the tables for use of the device in an electromagnetic environment.
2.5 Wiring and Connection Precautions CAUTION • Connect the power cord to a wall outlet with a protective ground. If current leakage occurs, there is a fear of electric shock. • Before plugging the power cord, verify that the wall outlet meets the specified power requirements. If not, the device may not deliver full performance, or a malfunction or a fire may occur. • Do not overload the electrical outlet. Abnormal heat generation may occur and result in fire.
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CAUTION • Securely connect the power cord, probe cable and foot switch cable to the designated connectors. If not, the device may not work normally or may be damaged.
2.6 After Use CAUTION • After use, turn OFF the power of the device. Cover the device with a dust cover to keep dust out. • Clean and disinfect the used accessories immediately so that any body fluids or chemical agents on them do not dry. • After use, clean the probe tip with gauze dampened with ethanol. Then, put the cap on it. • If the device will not be used for a long period of time, unplug the power cord from the power outlet. A fire may occur.
2.7 Maintenance and Check CAUTION • Each time the system starts, be sure to make a check of the device. If not, correct measured values cannot be obtained. • When replacing the printer paper, use the specified type. Failure to do so may cause a malfunction of the printer. • When replacing fuses, use the specified ones. Failure to do so may cause a malfunction or a fire. • When cleaning the cover of the device and touch screen, never use organic solvents such as thinners or abrasive detergents. The cover of the device and touch screen may be damaged. • If the touch screen becomes dirty, wipe it with a soft cloth or gauze dampened with ethanol or water. Other cleaning methods may damage the touch screen.
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CAUTION • After the cleaning, when the accessories are dry, visually check their exterior. • Only service technicians properly trained by NIDEK can disassemble and repair the device. NIDEK assumes no responsibility for accidents caused by improper repair. • When the device is sent back to NIDEK for repair or maintenance, wipe the surface of the device with a clean cloth dampened with cationic detergent, etc. (such as Benzalkonium chloride: 0.05 - 0.2% solution) which does not cause deformation or discoloration of the surface.
2.8 Disposal CAUTION • Follow local governing ordinances and recycling plans regarding disposal or recycling of device components when disposing of the device. Especially the disposal method of lithium batteries varies according to the government. This device has electric circuit boards with lithium batteries. When disposing of the circuit board, follow the instructions of the government. • When disposing of accessories such as probes, follow the recommended disposal procedure for medical wastes such as injection needles, infusion tubes, and metal surgical instrument as specified by your local medical institution and ordinances against infection and environmental contamination. • When disposing of packing materials, sort them by material and follow local governing ordinances and recycling plans.
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2.9 Labels In order to draw the physician’s attention, the appropriate warning labels are attached to the specified locations on the device.
§3 DEVICE DESCRIPTION 3.1 Exterior Features [Top view of the main body] Probe rest
Printer cover
Pilot lamp
[Front view of the main body]
Touch screen
Probe connector (P)
Probe connector (A)
[Left view of the main body]
Memory card slot
3-2 Probe rest The probe is placed here when it is not used. Printer cover Open this cover when replacing the printer paper. * As for the replacement of the printer paper, refer to “5.2 Replacement of Printer Paper” (P. 5-1). Pilot lamp Indicates whether power is supplied to the device. The green lamp lights up when power is supplied. Touch screen Shows various kinds of operation screens and measured data. By pressing the indicated switches, it is possible to make settings and input data. Probe connector (P) The probe for corneal thickness measurement (= Pachy probe, option) is connected here. Probe connector (A) The probe for axial length measurement (= A-mode probe) is connected here. Memory card slot The memory card is inserted here when adding IOL formulas.
3-3 [Rear view of the main body] Power switch
Fuse carrier
Inlet
Foot switch connector
External fixation lamp connector
External interface connector
Adjuster legs
Power switch The power of the device is turned ON/OFF by this switch. When the “|” side is pressed, the power is turned ON. The power is turned OFF by pressing the “{” side. Fuse carrier Fuses inside this carrier may blow if proper power is not supplied to the system. * As for the replacement of fuses, refer to “5.3 Replacement of Fuses” (P. 5-2).
Inlet The power cord is connected here. Foot switch connector The cable plug of the foot switch is connected here.