How to Interpret Eye Reports: A Guide for Disability Practitioners in the Post-Secondary Sector
Understanding and interpreting ophthalmological and optometric reports can be difficult for those of us outside the field. A basic understanding, however, is useful when there is a need to assess the impacts of an eye condition and make decisions around appropriate Reasonable Adjustments to course work and assessments. This article aims to provide some basic information and tips for interpreting eye reports - What should I look for? What do the figures mean? What questions should I ask the student?
Let’s look at a ‘mock’ eye report that may be presented as supporting documentation for registration for a tertiary education access support service. The important features to look for have been underlined and bolded:
Jane has been diagnosed with Keratoconus. This is a progressive condition. Today, her acuities were: L 6/60 and R 6/36 at full correction. Her binocular vision was 6/36. Her near vision was N18. Intraocular pressures were normal. Dilated examination showed healthy optic nerve and no clinical maculopathy. A Goldman field test showed her fields to be unrestricted in both eyes.
Firstly, it is important to look for the diagnosis. In this case, Jane has Keratoconus. Of course we can ask Jane to describe the impacts of this condition and/or we can ‘google’ it. The Australian Disability Clearinghouse on Education and Training (ADCET) website has a number of useful links to websites which describe eye conditions.
It is important to note that Jane’s condition is progressive. Jane’s needs may change as her eye condition deteriorates. This may need to be monitored to ensure Jane’s needs continue to be met.
Jane’s eye report outlines her acuities. Acuity is the ability to distinguish form and detail. In a word: clarity. Jane’s binocular (both eyes open) vision is 6/36. So, what does this mean?
Distance acuity is the measurement taken when we read an eye-chart on a wall when we visit an eye specialist. The measurement is expressed as a fraction. The numerator (top figure) represents the measuring distance and the denominator (bottom figure) represents the size of the letter that can be identified at that distance. The smaller the fraction, the worse the vision. So, an acuity of 6/48 is worse than an acuity of 6/18.
In Australia, the standard testing distance for distance acuity is 6m. Normal distance vision is recorded as 6/6. In the USA, this is known as “20/20” vision (measured in feet).
In practical terms, Jane’s acuity of 6/36 means that, at a distance of 6m, she can read the row of letters that a fully sighted person can read at 36m.
Below is a chart showing the parameters for the main levels of visual acuities:
Acuity |
Description |
6/6 = 20/20 |
Normal vision |
6/12 |
Reduced vision |
6/18 |
Low vision |
6/60 and less |
Legal blindness |
Let’s imagine that Linh has normal vision (6/6), Michael has low vision (6/24) and Azhar is legally blind (6/60). This means that Michael has to come to within 6m to see what Linh can see at 24m. Azhar has to come to within 6m to see what Linh can see at 60m.
The acuities in Jane’s eyes differ. Jane’s left eye is ‘legally blind’ (6/60) and her right eye is ‘low vision’ (6/36). The vision in her left eye is worse than her right. However, with both eyes open, her ‘good’ eye dominates. Her binocular vision is 6/36 and so Jane would be considered to be a person with ‘low vision’.
The table below shows terms that you may see to describe vision that is too reduced to identify any letters on a chart and therefore cannot be measured as a fraction:
CF |
Can count fingers at a specified distance |
HM |
Can see hand movements in front of the eyes |
LP |
Can perceive light and dark only |
NLP |
No light perception/totally blind |
The next feature to note on Jane’s eye report is her near vision. Near visual acuity tests a person’s central vision. It is usually tested by reading a hand-held card with diminishing print sizes. It tests the vision used for reading and ‘near’ tasks.
N8 is newsprint
N12 is the common print size used in daily life
N16-18 is commonly known as ‘large print’.
Although a person may be able to read or identify small print they may find it difficult to maintain this over a period of time. Individuals with low vision commonly experience visual fatigue. Jane’s near vision is N18. This is the smallest print size that Jane can read. Jane requires large print (minimum of N18) for hard copy reading and would probably experience significant visual fatigue with sustained reading, whether hard copy or electronic.
Finally, Jane’s report talks of her visual fields. Field tests report on peripheral vision. A reduction in a person’s field of vision can mean that while their central vision may be maintained, the surrounding context is lost. In a fully sighted person, visual fields are approximately 180° horizontally and 150° vertically.
A visual field of less than 60° will significantly impact a person’s ability to move safely within an environment. Jane has no diagnosed problems with her field of vision, at the time of the report.
It is important to be aware that an eye report usually describes best corrected vision. That is, the vision cannot be further improved by glasses or contact lenses. Further, the assessment has been performed in a clinical setting which provides ideal conditions. Therefore, they report on best case scenario on a particular day. The functional vision of the student may vary significantly from the level of vision reported in the clinical setting. Environmental factors such as poor or strong lighting may significantly reduce vision.
Of course, the best person to report on their functional vision and the impacts of the vision condition, is the person themselves. Here are some questions to ask the student about the condition and its impacts, that may or may not be covered by the eye report:
- does your condition impact both near and distance tasks?
- is the condition degenerative or stable?
- does the condition fluctuate?
- is this a new diagnosis?
- how does good light/poor light impact your vision?
- what other environmental/general factors impact your vision?
- do you have field loss?
- what mobility aids do you use?
- what low vision aids to you make use of?(if student has low vision)
- what technologies do you make use of?
When considering the best ways to support Jane, we now know that her condition impacts both distance and near vision. She is a person with low vision. She will require Reasonable Adjustments around both distance and near tasks. She has no current problems with her visual fields. Her condition is progressive and her needs may change. Any supports put in place, therefore, may need to be modified to ensure Jane’s needs continue to be met. By assessing the report and speaking to Jane, we should have the information required to provide her with the appropriate Reasonable Adjustments to ensure she has access to her course work and can be fairly assessed.
Content developed by Barbara Forehan (M.Ed). Barbara has worked as a specialist teacher for students who are blind or vision impaired for 23 years. She has also worked as a Disability Advisor in the tertiary setting.
Revised: July 2022