Overview
EN ISO 10944:2009 is the international and European standard specifying the minimum requirements and test methods for synoptophores, also known as major amblyoscopes or synoptometers. These ophthalmic instruments are essential for assessing, measuring, training, and developing a patient’s binocular vision. The standard defines how synoptophores should function to measure horizontal, vertical, and cyclo deviation across various gaze positions. EN ISO 10944:2009 takes precedence over ISO 15004-1 where differences occur, ensuring consistent quality and safety in clinical eye care.
Developed by ISO technical committee ISO/TC 172 in cooperation with CEN’s TC 170 on ophthalmic optics, the standard sets forth precise mechanical, optical, and functional criteria to ensure accurate and reliable synoptophore performance.
Key Topics
Scope and Purpose
- Specifies requirements for synoptophores used in testing binocular vision and eye alignment deviations.
- Covers optical, mechanical, and construction criteria essential for device accuracy and patient comfort.
Definitions
- Synoptophore: An instrument presenting adjustable, interchangeable visual targets to each eye independently.
- Visual targets: Includes images for simultaneous perception, fusion, and stereoscopic vision testing.
- Arms: Rotatable parts carrying ocular systems and targets, adjustable per patient needs.
Technical Requirements
- Interpupillary distance adjustment: 45 mm to 75 mm with graduations finer than 1 mm.
- Horizontal arm movement: ±40° independently adjustable.
- Vertical arm rotation: elevation up to 15°, depression up to 20°.
- Cyclotorsion movement: ±20° with 1° graduation.
- Chin-rest height adjustable between 75 mm and 125 mm relative to eyepiece centers.
- Construction allows compensation for refractive errors with precise lens holder placement.
Functional Specifications
- Easy insertion and removal of visual targets, clearly marked for identity and orientation.
- Uniform luminance and illumination control, including independent dimming and switching off of ocular illumination systems.
- Arms lockable together for synchronized movement or operated independently for precise measurements.
- Sets of visual targets to test simultaneous perception, fusion, and stereoscopic acuity.
- Minimization of contrast differences due to internal reflections or scattered light.
Testing and Verification
- Verification through type testing using accurate measuring instruments (angular precision ±5′ or better).
- Specific methods to check interpupillary distance, alignment of ocular axes, and chin-rest height.
- Tests and measurements to guarantee compliance with mechanical and optical tolerances.
Documentation and Marking
- Must include manufacturer's name, model, and compliance reference to ISO 10944:2009.
- Provide user instructions covering disinfection procedures, transport packaging compliance, and maintenance.
- Markings conform to IEC 60601-1 requirements for medical electrical equipment.
Applications
EN ISO 10944:2009 applies primarily to clinical and research settings where synoptophores are used for:
- Diagnosing and managing binocular vision disorders such as amblyopia, strabismus, and cyclodeviation.
- Training and rehabilitating binocular vision through controlled target presentation and vergence exercises.
- Objective measurement of eye misalignment in various gaze positions for accurate treatment planning.
- Quality assurance and manufacturing consistency for ophthalmic instrument producers.
- Ensuring patient safety and measurement accuracy in ophthalmology and optometry practices.
Compliance with this standard enables eye care professionals to rely on synoptophores that meet stringent optical, mechanical, and functional specifications, enhancing diagnostic and therapeutic outcomes.
Related Standards
- ISO 15004-1:2006 - Ophthalmic instruments - Fundamental requirements and test methods, Part 1: General requirements for all ophthalmic instruments. EN ISO 10944:2009 takes precedence in case of any differences.
- IEC 60601-1:2005 - Medical electrical equipment - General requirements for basic safety and essential performance; applicable for the electrical safety and performance of synoptophores.
- ISO 9801 - Ophthalmic instruments - Trial case lenses; relevant for lens holder specifications in synoptophores.
Adherence to EN ISO 10944:2009 alongside these complementary standards ensures comprehensive safety, performance, and interoperability of ophthalmic synoptophore instruments globally.
Keywords: EN ISO 10944:2009, synoptophore standards, ophthalmic instruments, binocular vision testing, amblyoscope requirements, synoptometer, medical eye equipment, ophthalmic optics standards, eye alignment measurement, ISO synoptophore test methods, ophthalmic instrument safety.