IAPB Essential List: Low Vision

The Essential Lists:

Version: First Edition (March 2017)

Why is this list important?

Despite major advances in eye care, an estimated 124 million people worldwide cannot have their sight fully restored with standard corrective measures. These people are regarded as having low vision. The majority of them, about 80 million people, however, have some residual vision that can be enhanced with special intervention: rehabilitation strategies, optical and non-optical devices, all of which can be utilized to assist them to carry out tasks that require vision.

What does this list contain?

This list provides recommendations for Instrumentation, Equipment and Low Vision Optical Devices and Assistive Devices for people with low vision. These are classified as desirable (D) or essential (E) across all three levels of service: primary (PRIM), secondary (SEC) and Tertiary (TER). See Figure 1.

How can quantities be calculated?

Suggested quantities are calculated for:

  • Equipment and instrumentation used for assessment of visual acuity and vision function1
  • Optical and assistive low vision devices used for assessment of vision/functionality. These are also issued or dispensed to patients.

The bracketed code after each number2 indicates that for any given clinic the device is likely to be issued to Many—20 or more (M), Some–10 or more (S) or a Few—5 or more (F) patients, relative to overall patient throughput3.

Three-tier model of care

Figure 1: This list is based on a three-tier model of care: Personnel at primary, secondary and tertiary level, able to refer appropriately for that level, both vertically for eye care services and horizontally to other service providers.

  • All Desirable (D) or Essential (E) items at a PRIMARY LEVEL will be Essential at all SECONDARY LEVEL or TERTIARY LEVEL
  • All Desirable (D) items at a SECONDARY LEVEL will be Essential (E) at TERTIARY LEVEL

Essential List Low Vision Addendum

Description Standard List Category (S) or Locally Purchased (L) Essential (E) or Desirable (D) Quantity
VISUAL ACUITY ASSESSMENT EQUIPMENT
Vision Screener test with Tumbling Es
To screen visual acuity
S E 1
Multiple Pinholes / Occluder
To determine best possible visual acuity
S/L E 1
EYE HEALTH ASSESSMENT EQUIPMENT
Pen Torch
To assess pupil reflexes and the health of ocular adnexa
S/L E 1
Amsler Chart
To assess central visual fields and metamorphopsia)
S D   1
VISUAL FIELDS ASSESSMENT EQUIPMENT
Confrontation test targets appropriate for use across the full range of acuities
To assess peripheral fields in profound sight loss
S E 1 Set
Description Standard List Category or Locally Purchased (L) Essential (E) or Desirable (D) Quantity Required
VISUAL ACUITY ASSESSMENT EQUIPMENT – distance
Measuring Tape ( > 3m)
To measure working distances for distance, intermediate and near visual tasks
S/L E 1
LogMAR design Visual Acuity (VA) Chart, -culturally appropriate optotypes
Letters’, E’s, C’s, numbers, symbols
S E 1
LogMAR designed VA Chart, Optotypes suitable for children
E’s, C’s, Pictures, symbols, Numbers
S E At least 1 per centre
Duplicate LogMAR VA Charts
To determine Visual Acuity with charts with different optotypes sequences
S D At least 1 per centre
Flip VA Charts with logarithmic progression of size , with sets of crowded optotypes (Letters, numbers, pictures, symbols)
To determine crowded distance Visual Acuity
S D At least 1 per centre
LogMAR designed Flip VA Chart, Single isolated symbols (Letters, numbers, pictures, symbols)
To determine distance Visual Acuity
S D At least 1 per centre
VISUAL ACUITY ASSESSMENT EQUIPMENT - near
Adjustable position Reading Lamp
To enable variation of illumination for the assessment of near vision functions
S/L D 1
LogMAR designed Near VA Optotype Charts, (Letters, Numbers, E's, C's   Symbols)
To assess near acuity using charts equivalent to the Distance Acuity Charts, calibrated appropriate working distances( i.e. 40cm)
S D At least 1 per centre
LogMAR designed Near VA Word   Text Charts (Letter Sequences)
To assess word and text acuity and reading performance in a culturally and language sensitive manner at appropriate working distances( i.e. 40cm)
S D 1
CONTRAST TESTS
Low Contrast Visual Acuity Tests
To assess Visual Acuity at reduced contrast
S D 1
Contrast Threshold Tests with large targets
To assess peak contrast sensitivity
S E 1
REFRACTIVE EQUIPMENT - objective
Autorefractor
To determine refractive error and corneal astigmatism
L D Optional
Retinoscope
To determine Refractive Error objectively
S/L E 1
Retinoscopy lens rack
For determination of refractive error
S/L D 1
Prism Set
To assess binocular status
S/L D 1
Lensmeter
To measure spectacle lens power
S/L E 1
REFRACTIVE EQUIPMENT - subjective
PD Ruler
To facilitate correct fitting of trial frame
S/L E 1
Trial Lens Set
For the assessment of refractive error by both objective and subjective methods
S/L E 1
Full Aperture Trial Lens Set
An alternative for the assessment of objective refraction
S/L D 1
Universal Trial Frame
To hold trial lenses in spectacle plane
S/L E 1
Paediatric Trial Frame
To hold trial lenses in spectacle plane
S/L D At least 1 per centre
Trial Lens Clips
To hold trial lenses in front of the patient’s spectacles
S/L E At least 1 per centre
Jackson Cross Cylinder
For measurement of astigmatism
S/L E 1
EYE HEALTH ASSESSMENT
Direct Ophthalmoscope
To assess central retinal integrity in the context of the degree and characteristics of visual functions
S/L E 1
Indirect Ophthalmoscope
To assess peripheral retinal integrity binocularly in the context of the degree and characteristics of visual functions
S/L D At least 1 per centre
Slit Lamp Biomicroscope and Volk Lens
To assess central retinal integrity, and anterior segment integrity, in the context of the degree and characteristics of visual functions
S/L E 1
Tonometer
To determine intraocular pressure
S/L E 1
Fundus Camera and/or OCT if available
To document the appearance of retinal pathology
S/L D 1 per centre (Unless an Ophthalmology treatment centre)
VISUAL FIELDS ASSESSMENT EQUIPMENT
Tangent Screen with range of Targets
To assess and quantify peripheral visual field size
S D 1
Visual Fields Analyser
To quantify the extent of visual field loss
L D At least 1 per centre
Arc or Bowl Perimeter suitable for Kinetic/Dynamic assessment
To assess and quantify full peripheral visual field size
L D At least 1 per centre
COLOUR VISION ASSESSMENT EQUIPMENT
Standard Illuminance C lighting (Northern Daylight Equivalent)
To ensure optimal lighting conditions for colour vision testing
S D 1
Large Target D15 Test
To assess colour vision status in vision impaired patients
S D At least 1 per centre
Description Standard List Category or Locally Purchased (L) Essential (E) or Desirable (D) Quantity Required
VISUAL ACUITY ASSESSMENT EQUIPMENT
Rudimentary Vision Test
To accurately quantify very poor levels of Acuity
S E 1 per centre
Preferential Looking Test / Grating Acuity Test
To assess Acuity in infants who cannot respond to optotype testing
S D 1 per centre
Vanishing Optotype Charts (i.e Cardiff Charts)
To assess Acuity in children who cannot respond to standard optotype testing
S D 1 per centre
VA Charts with a variable luminance control S D 1 per centre
Light Meter
A luxmeter to measure illumination at working plane, or a luminance meter
S/L D 1 per centre
REFRACTIVE EQUIPMENT - subjective
Binocular Trial Lens Holder
For testing or modifying refractive error corrections
S D 1
EYE HEALTH ASSESSMENT EQUIPMENT
Optical Coherence Tomographer (OCT)
To image and record signs of retinal pathology
L D
Optional, unless Ophthalmology Treatment Centre
1 per centre
Corneal Topographer
To measure corneal surface curvature and to record and quantify surface irregularity
L D
Optional, unless Corneal or Refractive Centre
1 per centre
Description Standard List Category or Locally Purchased (L) Essential (E) or Desirable (D) Quantity Required
MAGNIFIERS - hand
Low Powered (4, 5, 6, 8, 10DS )
Available with large field of view. Affordable, easy to use, some have illumination
S/L E   PRIM (6,10DS) SEC (wide range)   TER (extensive range) 1 (M)  1 (M/S)  1(S)
Medium Powered (12, 16, 20DS)
Available in lens designs to optimize optical quality and field size, Some have illumination
S E  PRIM (16DS)  SEC & TER (Full Range) 1(S)  1(M/S)
High Powered (24, 32, 40D, 48DS)
Restricted field of view. Mainly for spot reading
S D  SEC  E  TER 1 (F)  1(S)
MAGNIFIERS - stand
Dome/solid Hemisphere Magnifiers
All hemispheres give 1.5x enlargement. Different sizes available
S E   PRIM (1)   SEC (2)   TER (2 or more) 1 (M)   Particularly for Paediatric Services
Bar/Ruler Magnifiers
With option of line guide/ruler scale
S E   TER   1 (S) Particularly for Paediatric Services
Non Illuminated Stand Magnifiers (6 to 25DS)
With enlargement ratios over the range 2x, 2.5x, 3.2x, 4.0x, 5.0x, 6x, 8x, 10x, 12x, 16x, 20x
S E   PRI   SEC (3x, 5x)   TER (extensive Range)   1 (S)   1(S)
Illuminated Stand Magnifiers
In a range to compliment the non illuminated magnifiers. With enlargement ratios over the range 2x, 2.5x, 3.2x, 4.0x, 5.0x, 6x, 8x, 10x, 12x, 16x, 20x
S E   SEC ( 4x, 8x or more)   TER (extensive Range) 1(M)   1(M)   Particularly for clinics with large elderly cohort of patients in the developed world
MAGNIFIERS - spectacle
Half Eye or full aperture Readers (Plus powers: 4, 5, 6, 8, 10, 12, 16D) S/L E   PRIM (Sample Pair +4D or +6D)   SEC (Restricted Range)   TER (Full Range) 1(F)   1(S)   1(S)
Full Aperture high power (Plus powers: 20, 24, 32, 48D) L E   SEC (24, 48DS)   TER (Full Range) 1(S/F)   1(S)
Binocular Prismatic Half Eye Readers (Plus powers: 4, 6, 8D)
May provide binocularity
S/L E   TER 1(S)
Binocular Prismatic Half Eyes (10D)
May allow binocularity, especially in hyperopia
S/L D   TER 1(F)
TELESCOPES - hand held
Monoculars (2x, 2.5x, 3.2x, 4.0x, 5.0x, 6.3x, 8.0x, 10x, 12x)
Variable Focus.(Some should allow close focusing distances)
S/L E   PRIM(4x)   SEC (2.5x,4x,6x)   TER (Full Range)   1(F)   1(S/F)   1(S)
Binoculars (2.5x,4x, 6x, 8x)
To encourage binocularity
S/L E   SEC (One demonstration pair)   TER (Full Range) (S)  
1(S)
Particularly for Paediatric Mobility related Services
TELESCOPES - spectacle mounted
Monocular or Binocular Spec Mounted Telescopes, or telescope fitting kits
Custom made or incorporating Rx
S/L E   TER (F)
Near Vision Supplementary Caps S/L E   TER (F)
Bioptic Telescope fitting kits S/L D   TER (F)
FILTERS
Variety of locally available sunglasses in different shades   E   PRIM, SEC, TER 1 (S)
Anti-Glare Filters (With Transmission values of approx 5%, 15%, 30%. 60% in neutral tints and in brown/ amber/ yellow tints to reduce blue. Blue light cut off levels of 465nm, 505nm, 533nm, 550nm) S D   SEC   (moderate Range)   E   TER (extensive Range) 1(S)
Supplementary Range of filters of other colors (Include red and magenta filters for Achromotopsia and Cone Dystrophy) S D   SEC   E   TER (F)
Description Standard List Category or Locally Purchased (L) Essential (E) or Desirable (D) Quantity Required
DAILY LIVING - personal
Watch and clock with jumbo displays and high contrast
Increase the convenience of time telling
S/L SEC - D   TER - E 1 (F)   1(S)
Talking watch and clock
Increase the convenience of time telling
S SEC - D   TER - E 1 (F)   1(S)
Identifier starter kit with tapes and labels for low vision, bump dots and tactile markers
Increase effectiveness in categorizing and finding daily use items
S SEC - D   TER - E 1 (F)   1(S)
Large key holder
Improve convenience in daily living and self care
S/L SEC - D   TER - E 1 (F)   1(S)
Nail cutter with magnifier
Improve convenience in daily living and self care
S SEC - D   TER - E 1 (F)   1(S)
Needle threader
Improve convenience in daily living and self care
S SEC - D   TER - E 1 (F)   1(S)
DAILY LIVING - mobility
Super bright flash light torch
For safer mobility in poorly a lit environment
S/L PRI - D   SEC - D   TER - E 1(S/F)   1 (S)   1 (M/S
Canes for the visually impaired Long canes, folding canes.
To aid the mobility of LV persons with constricted visual field
S/L PRI - D   SEC - D   TER - E 1 (S/F)   1 (S)   1 (M/S)
DAILY LIVING - health
Medicine organizer pill box & pill cutter
To improve the convenience and safety in self administration of medication
S SEC - D   TER - E 1 (F)   1 (S)
Talking thermometer
To enable the low vision person to monitor health status with ease
S SEC - D   TER - E 1 (F)   1 (S)
Talking blood pressure monitor
To enable the low vision person to monitor health status with ease
S SEC - D   TER - E 1 (F)   1(S)
Talking personal scale
To enable the low vision person to monitor health status with ease
S SEC - D   TER - E 1 (F)   1(S)
Safety grab bar for toilet and bathroom
To improve the safety of self care
S SEC - D   TER - E 1 (F)   1(S)
DAILY LIVING - food preparation and dining
High contrast or tactile markers for knobs and switches on control panels of cooking stove, oven, microwave oven etc. S SEC - D   TER - E 1 (F)   1(S)
Colored food cutting boards for low vision To enhance contrast S SEC - D   TER - E 1 (F)   1(S)
Slicing knife with adjustable guide S SEC - D   TER - E 1 (F)   1(S)
Smart peeler L SEC - D   TER - E 1 (F)   1(S)
Jumbo timer for low vision with alarm S/L SEC - D   TER - E 1 (F)   1(S)
Measuring cups with large print S SEC - D   TER - E 1 (F)   1(S)
Talking kitchen scale S SEC - D   TER - E 1 (F)   1(S)
Colored bowls, plates and table mats for contrast enhancement of food and eating utensils S/L SEC - D   TER - E 1 (S/F)   1 (S)
EDUCATIONAL & VOCATIONAL
Calculator with large display and talking calculator S/L SEC - E   TER - E 1 (F)   1(S)
Reading and writing stands with adjustable tilt and height S/L SEC - E   TER - E 1 (F)   1(S)
Writing and signature guides S/L PRI - E   SEC - E   TER - E 1 (F)   1(S)   1 (M/S)
Writing paper with pre-printed bold lines S/L PRI – D   SEC - E   TER - E 1 (F)   1(S) 1 (M/S)
Bold felt tip and marker pens S/L PRI - E   SEC - E   TER - E 1 (S/F)   1 (S)   1 (M/S)
Digital devices and software to enhance information accessibility and exchange
Screen magnification systems. Some are freeware, such as magnifier for Windows 7 and Zoom for Mac OS. Others are Desktop Zoom3.5, Virtual Magnifying Glass. L TER - E 1
Screen reader programs. Some are freeware, such as NVDA, Thunder L TER - E 1
Mobile phone apps with accessibility features for VI L TER - E 1
Desktop CCTV reading and writing aids and portable video magnifiers S TER - E 1 (S)
Samples of Large and High Contrast Print
To demonstrate the significance of magnification and good contrast
L PRI – D   SEC - E   TER - E 1   1 1
RECREATIONAL Can participate in more interactive activities to strengthen social networking and skills
Auditory foam ball, basket ball, soccer ball S SEC - D   TER - E 1 (F)   1 (S/F)
Jumbo playing cards S SEC - D   TER - E 1 (F)   1 (S/F)
Jumbo chess set and other board games such as “Connect 4” S SEC - D   TER - E 1 (F)   1 (S/F)
Large dice S SEC - D   TER - E 1 (F)   1 (S/F)
Jumbo and tactile dominoes S SEC - D   TER - E 1 (F)   1 (S/F)

IAPB wishes to acknowledge and thank the following experts and organisations for their input and support in compiling this list from an IAPB Low Vision Workshop hosted by the Hong Kong Society for the Blind in November 2015. Present at the Workshop:-

  • Hasan Minto – Director of SSD, Public Health, Brien Holden Vision Institute, Pakistan
  • Associate Prof Jonathan Jackson – Head of Optometry & NICRN (Vision) joint clinical lead, Belfast Health & Social Care Trust, Northern Ireland
  • Prof Ian Bailey – Professor of Optometry & Vision Science, University of California, USA
  • Philip Hoare – Procurement Manager, IAPB UK
  • Joseph Cho – Director (Clinical & Vocational Services), The Hong Kong Society for the Blind
  • Kandle Mann – Assistant Centre Coordinator, The Vision 2020 Low Vision Resource Centre
  • Andrew Ay – Centre Coordinator, The Vision 2020 Low Vision Resource Centre
The following persons also contributed to the list:-
  • Prof Jill Keeffe – L V Prasad Eye Institute, Hyderabad, India
  • University of Melbourne Department of Ophthalmology (Honorary Appointment)
  • Dr Renee du Toit –Independent Eye Health Consultant, South Africa
Photo by Sally P
[1] Unless specified to the contrary, the number of items required is per consulting room /assessment area. With expensive specialist equipment, such as automated threshold visual field analysers or OCT imaging systems, it is assumed that only one is needed e.g. centres delivering only tertiary low vision and rehabilitation care might only need 1 OCT per site. But in large SEC or TER centres, equipment can be increased according to the patient population and the services provided e.g. centres providing intravitreal treatments might need multiple OCTs.

[2] e.g. Low Powered Hand magnifiers for a PRIM, the figure 1(M) means:
• For assessment: one of each a 6 & 10 DS hand magnifier • For issue: many (M), relative to the patient throughput, should be available.

[3] Quantifying “M, S, F” will depend on a number of factors including, the size and nature of the clinic, the patient throughput, the stock storage and replacement policy and the supply network system and timescale. The numbers above are indicative to get the right quantities of inventory while the clinic is being established, and working on the assumption that the inventory will be updated annually. Once the clinic is up and running the orders can be adjusted according to the frequency of dispensing and the available stock.

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