Fields on the go

The assessments of visual fields in a low vision setting is an important part of assessing vision. No longer is the test aimed at disease detection, though obviously changes to visual fields are always a useful indicator of disease progression, but rather a way of assessing the potential impact of any loss of field upon function. It then makes it easier for the eye care practitioner to decide on any particular management strategy, such as help with mobility or addressing the way a person’s home environment is set up.

Furthermore, the loss of visual field is often a key factor in the decision as to whether a consultant ophthalmologist is likely to certify someone as eligible for registration as either sight or severe sight impaired. Unlike acuity values, where specific values are cited as guidance, the loss of field and the impact of significant glare or photophobia are left much more to the discretion of the clinician in deciding upon their likely impact upon life and therefore eligibility for certification. Bilateral hemifield loss is usually considered sufficiently severe to warrant registration, while major encroachment upon the inferior field of each eye is also thought to have a great enough impact upon mobility to also pass any requirement.