None listed
Conditions
Brief summary
Impaired motor function and cognitive confusion are the most common diagnostic symptoms associated with "stroke". Few acute clinical investigations of visual function are conducted even though far greater volumes of cortical and subcortical regions of the brain are directly involved with visual functions than with motor function. Van Essen et al (1984) first highlighted the vast number of visual areas and volume of cortex attributed to visual sensory processing, visual attention, visuo-motor functions and visually driven emotional processing. Furthermore the eye and the brain share similar embryonically derived vascular tissues and blood flow making vision defect a likely companion to a brain blood disorder (stroke). Over the last decade Rowe et al (2009), Spotfforth et al (2017) and Quinn et al (2018) have described significant persistent visual deficits following stroke. Of those affected common visual deficits up to a year later include visual field loss (hemianopia, quadrantanopia) ,perceptual disorders (visual inattention/neglect) and eye movement disorders. Rowe et al (2009) also noted the large proportion of ocular alignment deficits co-morbid with visual field defects. Most recently Quinn et al (2018) highlighted the incidence of visual field deficits with coexisting visual neglect in post stroke survivors. Hemifield neglect has long been known as a perceptual deficit sometimes associated with stroke although when tested it is most often tested manually by line bisection or star cancellation even though stroke itself is usually defined by motor impairments. Application of sophisticated visual field analyzers such as the Humphrey have seldom been utilized in hospitalized stroke patients given that most cases involve elderly patients limited in mobility and who suffer motor impairment for at least 24 hours. Thus the purpose of this study was to consider whether visual field losses can be identified and quantified in the acute stages of stroke using an ipad based bed side perimetry app, The Melbourne Rapid Fields (MRF), developed to measure visual acuity and visual field integrity. The neuroanatomical site of lesion was also considered in relation to field deficits to evalute the clinical and radiographic imaging patterns with the patient’s visual acuity and visual field intergrity.
Interventions
Vision and the visual processes occupy a large volume of brain yet stroke is diagnosed by its affects on motor processing. This is partly because to quantify the effects of stroke on visual capacity other than by screening tests, such as confrontation, is not easy especially in the early stages after acute stroke onset. At these stages patients are often debilitated or bedridden and can not undertake the complex, specialised testing needed for such evaluation.
We hope to address this limitatio
Vision and the visual processes occupy a large volume of brain yet stroke is diagnosed by its affects on motor processing. This is partly because to quantify the effects of stroke on visual capacity other than by screening tests, such as confrontation, is not easy especially in the early stages after acute stroke onset. At these stages patients are often debilitated or bedridden and can not undertake the complex, specialised testing needed for such evaluation. We hope to address this limitation and better define the characteristics of acute stroke on vision and visual processing by using modern applications shown on portable tablet devices. Our observational study was performed on one hundred and ten, consecutive patients admitted between June,2017-May,2018 to the Neurology Ward at Sunshine Hospital, Melbourne, and who were diagnosed as having suffered a stroke by conventional clinical diagnostic methods. All patients were bed-bound and were requested within 1 week after admission to volunteer for vision testing using two iPad applications “Melbourne Rapid Field” (MRF) App (visual acuity (threshold spatial vision), threshold visual field) and the "UNSW L-R Eye-Hand Coordination"App (visuo-motor capacity). Testing was performed at the bedside of stroke patients who volunteered to participate in this study consistent with our ethics clearance. Their visual acuity, visual field extent and visuo-motor skills were followed up at 3, 6 and 12 months to monitor recovery. The health care of all patients is being administered based on standard clinical practice and the vision testing outcomes will not impact on this management.
Sponsors
The La Trobe University,Melbourne
Eligibility
Sex/Gender
All
Age
30 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Any patient admitted with a clinical diagnosis of an ischemic acute stroke (within a week since the onset of the stroke) with no history of ocular, cognitive or neurological conditions that could be expected to impact on their visual acuity, visual fields or visuo-motor capacity. All controls will have an age-similar profile to our stroke group and will have normal vision, eye health, brain health and systemic health. They will meet our exclusion criteria.
Exclusion criteria
Patients with: 1. medical record of co-existing ocular conditions such as glaucoma, macular degeneration, diabetes, cataracts or other causes of monocular vision loss (<6/9) 2. Severe cognitive or physical impairment that limits performance on tests 3. Inadequate English to understand the instructions for the testing 4. Poor reliably (errors >50%) on the visual fields 5. Acute stroke resultant to a heammorragic cause Same exclusion criteria apply to the controls
Outcome results
None listed