Hypoperfusion and vision
Research type
Research Study
Full title
Effect of hypo-perfusion on visual function
IRAS ID
135824
Contact name
Fiona Rowe
Contact email
Sponsor organisation
University of Liverpool
Research summary
Changes in visual function occur frequently with cerebro-vascular disease and may be an indicator of pending stroke. In particular, carotid artery disease can cause transient or permanent visual loss along with other visual impairments such as Horner’s syndrome, ischaemic optic neuropathy and visual field loss. Many patients have reduced retinal arterial blood flow. Surgery has been reported to improve vision in cases where visual function had been affected. However, some patients report improved clarity of vision postoperatively despite having been visually asymptomatic prior to surgery. This may represent a very gradual impairment of visual function due to effects of hypoperfusion that has gone undetected by patients, but which is very apparent postoperatively by the sudden favourable change in vision following improved arterial circulation.
Given the lack of literature addressing this area, we wish to undertake a feasibility project which will provide information to plan a future large study of effects of cerebral hypoperfusion on visual performance. We wish to evaluate the effect of cerebral hypoperfusion on visual function by measuring form vision, contrast sensitivity and threshold visual fields pre and post operatively for carotid endarterectomy and open heart surgery. Patients will be asked to undertake visual assessments lasting approximately 40 minutes before and after their surgery. Results will be analysed for changes in these visual parameters.
Our study aims to determine:
• the optimum assessment procedure to identify reduced visual function before surgery and changes in visual function due to surgery;
• patients’ views of the acceptability of the visual assessments.
• the numbers of patients with reduced visual function prior to carotid and open heart surgery;
• the numbers of patients who would be eligible for visual assessments postoperatively;
• the feasibility of undertaking visual assessments in the early postoperative period.REC name
North West - Liverpool Central Research Ethics Committee
REC reference
14/NW/0184
Date of REC Opinion
2 Jun 2014
REC opinion
Further Information Favourable Opinion