What low vision is, why “untreatable” is the wrong word for it, how registration works in the UK, and the help that follows from it.
What low vision means
Low vision is sight loss that cannot be corrected by glasses, contact lenses, medication or surgery. The phrase describes what remains rather than what has gone: most people with low vision retain useful sight, and the question is what can still be done with it.
It takes several forms, and they are not interchangeable. Visual acuity may be reduced, so detail blurs while the field stays whole. Visual field may be lost instead, leaving sharp vision in a narrowing tunnel, or a blank patch in the centre with good peripheral sight around it. Contrast sensitivity may fall, so that a pale step against a pale floor becomes invisible while a letter chart is read without difficulty. Glare may become disabling, turning a bright day into a problem rather than a pleasure.
Someone with central loss and someone with peripheral loss have almost opposite experiences. The first cannot read a face but can cross a room; the second can read fine print but walks into furniture. Lumping them together as “poor sight” obscures what each actually needs.
It is not untreatable
This is the part older advice gets most wrong, and the error does harm, because a person who believes nothing can be done does not go and find out.
Two different things are being confused. The underlying condition is frequently treatable. Wet age-related macular degeneration is now managed with anti-VEGF injections that can halt the deterioration and sometimes recover sight — a treatment that barely existed twenty years ago and has changed the outlook entirely. Glaucoma treatment slows or stops progression. Diabetic retinopathy responds to laser and injections, and to better glucose control. Cataract is curable outright by surgery.
The sight that is already lost is rehabilitated rather than cured, and that is a discipline in its own right rather than a consolation prize. Low vision services assess what sight remains, supply and train people in aids, and teach techniques — eccentric viewing, for instance, which trains someone with a central blind spot to look slightly to one side so the image falls on working retina. People relearn reading, cooking, getting about.
So “untreatable” is wrong twice over: it understates what medicine can do about the cause, and it ignores rehabilitation altogether. Neither error is harmless.
What causes it
In the UK the commonest cause is age-related macular degeneration, which attacks central vision and leaves the periphery intact. Glaucoma does the reverse, eroding the field from the edges inward, often unnoticed until a great deal has gone. Diabetic retinopathy damages the retinal blood vessels. Cataract clouds the lens, and unlike the others is routinely reversed by surgery.
Beyond those: inherited retinal conditions such as retinitis pigmentosa, injury to the eye or head, stroke and brain tumours, which typically take a section of the visual field rather than sharpness, and optic nerve disease.
The pattern of loss follows the cause, which is why diagnosis determines what help is useful.
Registration, and what it is for
The UK has a formal register, and it is the gateway to most practical support.
Registration is voluntary. A consultant ophthalmologist completes a Certificate of Vision Impairment, known as a CVI — the BP1 form in Scotland — and there are two categories.
Sight impaired, formerly partially sighted: acuity between 3/60 and 6/60 with a full field; or up to 6/24 with a moderate field reduction or a cloudy central field; or up to 6/18 where a large part of the field is missing.
Severely sight impaired, formerly blind: acuity below 3/60 with a full field; or between 3/60 and 6/60 with severe field reduction such as tunnel vision; or 6/60 or better where the field is very reduced, particularly if much of the lower field has gone.
The certificate goes to the local council, where it acts as a referral for a social care assessment and reaches the sensory impairment team. Registration itself is completed with the council, and has to be repeated after moving to a different authority.
Help is available without registering. But a great deal of it becomes automatic with a certificate, and the assessment it triggers is the single most useful thing in the process.
For readers in the United States
There is no equivalent register. The comparable concept is statutory blindness, defined in federal regulation as central visual acuity of 20/200 or less in the better eye with a correcting lens, or a visual field whose widest diameter is no greater than 20 degrees.
It functions as an eligibility threshold for Social Security disability benefits and for certain tax provisions and state services, rather than as a local authority register that triggers a social care assessment. Services are correspondingly more fragmented, and generally have to be sought out individually rather than following from a single certificate.
What registration opens up
At either level of registration: a free NHS sight test, a voucher towards complex lenses, a Disabled Person's Railcard, a free local bus pass, referral to low vision services, a council needs assessment, library material in audio, large print, braille and digital formats, and in some circumstances a council tax reduction.
For severely sight impaired registration, additionally: Blind Person's Allowance, an extra tax-free amount which can be transferred to a spouse or civil partner if unused; a 50% reduction on the TV licence; eligibility for a Blue Badge; free postage on Articles for the Blind, which covers large print, braille and audio; and a Cinema Exhibitors' Association card giving a companion free entry.
Several things that people assume come with registration are claimed separately: Personal Independence Payment for those aged 16 and over, Attendance Allowance at state pension age, and Disability Living Allowance for children. Registration can support those claims without granting them.
Low vision services
A low vision assessment is a different appointment from a sight test. It measures what the remaining vision can do rather than what prescription corrects it, and it usually results in aids supplied on loan along with training in using them — which matters more than the equipment, because a magnifier used at the wrong distance is simply a heavy piece of glass.
Many hospital eye departments have an Eye Clinic Liaison Officer, whose job is to pick people up at the point of diagnosis and connect them to practical and emotional support. They are worth asking for by name, because the diagnosis appointment is rarely the moment anyone absorbs information about what happens next.
The RNIB and local sight loss societies run helplines, equipment demonstrations, befriending and peer groups. Social services provide mobility training, home assessments and equipment.
The technology has changed completely
Older guidance lists magnifiers, monoculars, telescopic spectacles and desktop video magnifiers. Those remain useful, particularly for sustained reading, and a good stand magnifier is still hard to beat for a crossword.
But the device most people already own has replaced a great deal of dedicated equipment. Every current smartphone includes system-wide magnification, adjustable text size, high-contrast and inverted display modes, and a full screen reader — VoiceOver on iPhone, TalkBack on Android — capable of reading anything on screen aloud. The camera works as a magnifier with a frozen image that can be enlarged and examined. Optical character recognition will photograph a letter, a menu or a medicine label and read it out. Applications exist that describe surroundings, and others that connect a user to a sighted volunteer by video.
None of it costs anything beyond a phone, and almost all of it is built into the operating system rather than requiring purchase. Anyone whose information about aids dates from a decade ago is likely to be unaware of most of it.
E-readers deserve a separate mention, because adjustable type size and backlighting make them more accessible than large print editions, which are limited in range and awkward to hold. Audiobooks and the RNIB Talking Books service cover the rest.
Work
Losing a job is not the automatic consequence that older advice suggests.
Sight loss is a disability under the Equality Act 2010 — the Disability Discrimination Act in Northern Ireland — and employers have a legal duty to make reasonable adjustments. That can mean screen reading software, magnification, lighting changes, altered duties, different hours or a changed workstation.
Access to Work is a government scheme that funds much of this, including equipment, software, travel where public transport is not workable, and support workers. It is applied for by the individual rather than the employer, and the grant is not means tested.
A diagnosis is a reason to find out what adjustments exist, not a reason to resign.
Driving
A car driver must meet the legal standard: reading a current-style number plate at 20 metres, visual acuity of at least 6/12 on the Snellen scale, and an adequate field of vision without significant central defects.
Anyone who falls below that, or who develops a visual field defect, must tell the DVLA — the DVA in Northern Ireland. Failing to do so is an offence and invalidates insurance.
Giving up driving is one of the losses people feel most sharply, and it is worth knowing in advance that the concessionary travel and railcard entitlements above exist partly to offset it.
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