Many patients think they have a left visual field cut when they might actually have left visual neglect.
Knowing the difference between these conditions is critical for creating effective compensation techniques and finding appropriate treatment.
Here’s a quick guide to the difference between left visual field cuts and left visual neglect, along with treatments for each condition.
Visual Field Cuts
Hemianopsia (AKA visual field cuts, homonymous hemianopsia) is a blindness or reduced vision in half the visual field. This is a problem in brain function rather than the eyes.
Each half of the brain processes visual information from the opposite side of the body. The right hemisphere processes the left side of the world.
When the right hemisphere is damaged, it can impair the processing of visual information on the left side, resulting in a left visual field cut.
This is an example of what someone with a left visual field cut may see:
Treatment for Visual Field Cuts
A compensation technique called scanning can help patients with visual field cuts adapt to their condition. It involves turning the head to the affected side to take in more visual information.
This compensation technique can help someone with left visual field cuts begin to notice things on their left side. Although scanning won’t be a natural instinct, it can become a habit with enough repetition.
Compensation techniques do not address the root problem, however. If you’re interested in more comprehensive solutions, you can search for vision rehabilitation clinics in your area.
Visual rehab clinics are rare because there isn’t enough evidence for the practice to be widely accepted yet. But if you dig around enough, hopefully you can find options in your area.
Unlike field cuts, visual neglect (AKA one-sided neglect, hemineglect, hemispatial inattention) is an attention disorder where the patient does not notice stimuli on one side.
This is not an issue with visual information. Instead, it’s an issue with attention.
If you approach someone with left neglect, for example, and you approach from their left side, they will not notice you. They’re not being rude or aloof – they just literally cannot process that you’re there.
This condition happens more frequently in stroke patients where the parietal lobe has been affected.
If someone with hemineglect is asked to fill in the numbers on a clock, they might do something like this:
Image from Journal of Neurology
Treatment for Visual Neglect
Visual Scanning Training
Visual scanning training is a great compensation technique for hemineglect. Patients with hemineglect can train in turning turn towards their affected side to take in the environment on that side.
This will not feel natural at first – and the patient will likely need training and reminders – but it can help compensate for the lack of attention on the affected side.
For example, a stroke survivor with one-sided neglect can practice scanning a page from left to right. To make this easier, you can mark the neglected side with highlighter to ensure that you scan all the way to that side.
Limb Activation Treatment
Other treatments involve “limb activation treatment.” This requires moving the affected limbs within the neglected environment.
A patient with left visual neglect can perform arm exercises with the left arm or leg, and it may help improve attention on the affected side.
Even though the patient likely cannot see their affected limb moving, it has been shown to help with hemineglect because of the link between visual attention and motor function.
Visual Field Cut vs Neglect
Although field cuts and hemineglect manifest in similar ways, they are different conditions.
Field cuts involve partial blindness where the patient cannot see on the affected side. It’s a problem with visual information processing in the brain, not a problem with the eyes.
Hemineglect involves inattention on the affected side. It’s a problem with awareness.
Patients with field cuts can benefit from vision restoration therapy while patients with hemineglect can benefit from limb activation therapy.
A useful compensation technique for both conditions is scanning, which involves turning towards the affected side to process what’s there.
Hopefully this guide has helped you identify the difference between field cuts and hemineglect, along with treatments to consider with your medical team.