New study looking at post-stroke visual impairments
A new study, published in Wiley Brain and Behaviour, has examined the wide range of visual impairments developed by stroke survivors.
Approximately 65% of acute stroke survivors have visual impairment which typically relates to impaired central or peripheral vision, eye movement abnormalities, or visual perceptual defects. Symptoms can include blurred or altered vision, double or jumbled vision, loss of visual field, reading difficulty, inability to recognise familiar objects or people and glare. Post stroke visual impairment (PSVI) is currently an under researched area. However the full range of impairments is currently unknown.
The University of Liverpool has reported that in order to profile the full range of visual disorders researchers from its Department of Health Services Research, led by Dr Fiona Rowe, examined the visual impairment screening/referral forms from nine hundred and fifteen post-stroke patients from twenty NHS hospital trusts.
The researchers found that the average number of days post-stroke onset before a visual assessment was conducted was twenty two.
Once assessed 92% were confirmed to have a visual impairment, of these 24% had reduced clarity of vision (central visual acuity), 16% had developed a squint (strabismus), 68% had impairments to the way their eye or eyes moved (ocular motility disorders), and 52% had peripheral visual field loss. 15% had developed a condition causing them to ignore everything on one side of their visual world. The condition, known as visual inattention, usually affects people who have had a right sided stroke and they ignore things on their left side. Overall 84% were visually symptomatic with visual field loss the most common complaint followed by blurred vision, reading difficulty, and diplopia.
Treatment options were provided to all with confirmed visual impairment. Targeted advice was most commonly provided along with refraction, prisms, and occlusion.
Fiona Rowe said “There are a wide range of visual disorders that occur following stroke and, frequently, with visual symptoms. There are equally a wide variety of treatment options available for these individuals. Our research highlights the fact that ALL stroke survivors require early screening for visual impairment and warrant referral for specialist assessment and targeted treatment specific to the type of visual impairment.”