Strabismus (squint) is a misalignment of the two eyes affecting 4% of adults. Uncorrected
this may cause functional visual problems including double vision, visual confusion, loss of
stereopsis (3D vision) and binocularity (the coordinated use of the two eyes together),
asthenopia (eye strain) and headaches and the requirement to adopt an abnormal head
posture for vision. There are negative effects in terms of reduced ability to drive and
independence, and increased risk of falls. Even in the absence of functional visual issues,
strabismus in adults is associated with psychosocial difficulties including low self-esteem,
abnormal mood, reduced quality of life, reduced employment opportunities, discrimination
and psychiatric issues.
Non-surgical management options include prism lenses, eye exercise and botulinum toxin
procedures in a small percentage but many cases will require surgery to achieve significant
improvement. There is good evidence that surgery is very safe and highly effective in
addressing these issues in clinically suitable cases. Current evidence shows that even
patients with longstanding strabismus without diplopia demonstrate measurable benefits in
binocularity, function, quality of life and psychosocial interactions after strabismus surgery.
There is excellent cost-utility for strabismus surgery at between approximately £1,000-1600
dollars/QALY (NICE cut off for cost effectiveness is less than £20,000 per QALY). Strabismus
surgery in adults should not be rationed on non-clinical grounds and patients with
strabismus should be considered as candidates for surgical treatment whether or not they
experience double vision.