Vision Problems After Stroke: Field Loss, Neglect and What Rehabilitation Can Do

Vision problems after a stroke come in several distinct forms: loss of half the visual field, double vision from eye-movement problems, difficulty interpreting what the eyes send, and inattention to one side of space, and they need different handling. They are common enough to be routinely assessed as part of rehabilitation, and they are among the problems most often missed, because the person cannot always report what they cannot perceive¹.

I did not have a visual field loss. The man in the bed opposite me on the rehabilitation ward did, and watching him taught me more about how the brain builds a picture of the world than anything I read afterwards. He ate the right half of every meal and pushed the tray away. He was not being fussy and he was not depressed. As far as his brain was concerned, the left half of that plate did not exist, and nothing about his behaviour would tell you otherwise unless you knew to turn the plate round. This sits inside the wider picture in neuro-rehabilitation and overlaps heavily with cognitive rehabilitation after brain injury.

What actually goes wrong with vision after a stroke

A stroke can affect vision at four different points: the visual field, the movement of the eyes, the brain’s interpretation of the image, and the attention paid to one side of space. Each produces a different experience, and lumping them together as “eye problems” is how people end up with the wrong help¹.

Field loss is the one people picture. Damage to the visual pathway behind the eyes takes out a matching portion of the field in both eyes, most commonly the same half, which is called hemianopia. Eye-movement problems are different again: the eyes themselves are fine but they no longer point in perfect agreement, so you get double vision, blurring, or trouble following a moving object. Processing problems sit further along still, where the picture arrives intact but the brain struggles to make sense of it, so a familiar face or an object on a cluttered worktop takes far longer to recognise than it should. And then there is neglect, which deserves its own section.

Neglect is not blindness, and that is what makes it dangerous

In visual neglect the eyes and the visual pathway can be working normally, but the brain does not attend to one side of space, so the person does not experience anything as missing. That absence of awareness is the crucial difference from a field loss, where people generally know their field is cut and learn to compensate by turning the head².

You can see why this is the more disabling of the two. A person with hemianopia looks left because they know they cannot see left. A person with neglect has no sense that left exists to be looked at. They shave one side of the face, dress one arm, read the right half of a sentence and find it makes a sort of sense. Families usually spot it first, and often interpret it as carelessness or confusion, which is unfair and unhelpful to everyone involved. Neglect is best understood as a problem of attention, which is why it is handled by the same part of the team that deals with attention and memory in cognitive rehabilitation after brain injury, rather than by an optician.

How vision gets assessed, and who does it

Vision should be assessed as part of the rehabilitation team’s work, with an orthoptist, optometrist or ophthalmologist involved where the service has access to one, because the four problems above need different tests. NICE is clear that rehabilitation begins with an assessment of the person’s actual difficulties rather than assumptions about them³.

The practical questions are separate: is the visual field intact, are the eyes moving together, is the brain interpreting the image, and is one side of space being attended to. An occupational therapist watching you make a cup of tea often learns more about neglect than a chart on a wall, because neglect shows up in real, cluttered, two-sided tasks rather than in a tidy clinic test. This is one of the clearest examples of why the rehabilitation team is a team and not a single clinician, and why the assessment should feed straight into goal-setting in rehabilitation rather than sitting in a letter.

What treatment can and cannot do

The honest evidence position is that compensation strategies have more support than anything that restores a lost visual field, and the research on retraining attention after stroke is genuinely limited. Cochrane’s review of cognitive rehabilitation for attention deficits after stroke found the evidence insufficient to support or refute a lasting benefit on daily function, which is a frustrating answer but the true one⁴.

That does not mean nothing is done. Systematic scanning training teaches a deliberate, practised sweep to the affected side until it becomes automatic, and it works on the same principle as everything else in rehabilitation: intensive, repetitive, task-specific practice, described in how neuroplasticity drives recovery. Environments get adapted, so the phone, the plate and the kettle move to the side that is seen. Tasks are set up differently, so reading uses a finger or a ruler to anchor the missing edge of the line. Where double vision is the problem, an eye specialist may try prisms or temporary patching. None of this is glamorous, and all of it is the sort of thing occupational therapy after stroke does well.

How vision problems sabotage the rest of your recovery

Untreated vision problems quietly undermine everything else in rehabilitation, from falls to therapy that looks like poor motivation. Falls are already one of the most common problems after a stroke, with a risk as high as 73% in the first year after a severe stroke, and missing a kerb, a step or a bag on your affected side is a direct route to the floor².

It goes further than falls. Someone who cannot see or attend to the left half of a table will do badly at a task that requires reaching across it, and the note in the file may say poor engagement when the truth is a visual problem nobody tested. Reading, screens and crowded shops become exhausting, which pours straight into post-stroke fatigue and the low mood covered in post-stroke depression. It also shapes what “walking again” means in practice: about 75% of people walk independently by 3 months, but fewer than 50% reach community-level walking, and being able to see the world you are walking through is part of that gap, as falls and balance after stroke sets out⁵.

What to ask for

Ask directly whether your vision has been assessed, which of the four problems you have, and what the plan is for compensating, because vision is one of the easiest things to leave off a rehabilitation plan. Guidelines expect rehabilitation to address the difficulties a person actually has, and that means the ones nobody has looked for yet³.

The questions I would take in are plain ones. Has anyone tested my visual field. Are my eyes working together. Is anyone checking whether I am missing one side of space, and has my family been asked what they have noticed at home. What should we change about the layout of the kitchen. And, separately and seriously, what does this mean for driving, which is a matter for a proper assessment and your national licensing authority, not for a forum or a website. Vision is not an optional extra bolted onto recovery. It is the channel through which most of the rest of rehabilitation arrives, and if it is compromised, everything else runs uphill.