Short wavelength automated perimetry, also known as blue-on-yellow perimetry, tests visual field sensitivity to blue stimuli presented on a bright yellow background. It preferentially stimulates the blue-sensitive pathways.
Method
Automated perimeters present small blue lights at various locations while the patient fixates centrally and responds when stimuli are seen. The yellow background suppresses other cone responses, enhancing isolation of short-wavelength channels.
- Thresholds are compared with age-matched normative data
- Testing protocols resemble standard automated perimetry but with different stimuli
- Requires careful control of adaptation and lens tint effects
- May be more demanding for patients due to subtle stimuli
Clinical Role
This technique has been investigated for early glaucoma detection and assessment of optic nerve disease, where blue-yellow pathways may be affected before standard pathways. It can reveal functional loss earlier in some individuals.
- Findings are interpreted alongside white-on-white visual fields and structural imaging
- Use is more common in specialist centres than in routine practice
- Lens opacities and media changes can influence results
- Ongoing research continues to refine its clinical utility
