visual disturbance (seeing haloes around light sources)

Last reviewed 01/2018

This symptom may indicate intraocular pathology.

Pupillary dilatation causes an increase in intraocular pressure which results in transient oedema of the cornea. This can cause haloes to be seen around light sources e.g. street lamps. If there is a painful red eye associated with these symptoms then there may be an acute glaucoma or inflammation of the iris or ciliary body and urgent referral should be made.

Other causes of haloes include:

  • corneal disease
  • lens opacities

Note that jagged haloes which change shape are generally due to migraine. However be cautious in labelling haloes around lights as being migranous in patients who have not suffered from previous migraines (especially those over 50 years old).