• What is a visual field test?
• How long will it take?
• Driving visual field test
• What equipment is used?
• What do you need to bring?
• Who will do the test?
• What happens to the results?
• When is this test done?
• Purpose of assessment
• If you cannot keep the appointment
• Gabapentin
• Vigabatrin
  
  
• a word document for patients
  
  
• Visual fields for students
  
  
• Newcastle page

• What is glaucoma?
  • Text
  • Animation of glaucoma
  • Professionals: notes
  • SLT laser
• Angle closure glaucoma & narrow angle glaucoma / laser iridotomies
  • Animation of laser iridotomy
  • Chronic narrow angle glaucoma
  • Text
  • Professionals: notes
• Internat. Glaucoma Association
• Intraocular hypertension
• Low tension glaucoma
• Pre-perimetric glaucoma
• Visual field testing
• Drops & tablets for glaucoma
• Animations etc
  • Glaucoma
  • Laser iridotomy
  • Trabeculectomy
  • Rubeotic glaucoma
  • Progression model
  • SLT laser
• Rubeotic glaucoma
  • Text
  • Rubeotic glaucoma animation
  • Professionals: notes
• Students: Cases
  • Case 1
  • Case 2
  • Case 3
  • Case 4
  • Case 5
  • Case 6
  • Case 5
  • Case 8
  • Case 9
  • Case 10
  • Case 11
• Pseudoexfoliation..link
• Pigmentary glaucoma ..link
• Trabeculectomy
  • Text
  • Animation
  • Audit
    • 2006 with photos
    • 2008
• More technical
  • Corneal thickness & IOP
  • Hypotony
  • Arcuate scotomas ..glaucoma?
• Glaucoma letters
• Glaucoma photos (professionals)

A visual field test measures how much 'side' vision you have. It is a straightforward test, painless, and does not involve eye drops.
Essentially lights are flashed on, and you have to press a button whenever you see the light. Your head is kept still.. you have to rest your chin on a a chin rest.
The lights are bright or dim at different stages of the test. Some of the flashes are purely to check you are concentrating.

Each eye is tested separately, and you should allow 15-45 minutes to have the whole test.

These are usually carried out by various optometrists seceted by the DVLA (Driving and Vehicle Licencing Centrein Swansea). The hospital department does not usually communicate with the DVLA

A doctor may ask only for a driving licence visual field test if a oatient requests, which takes 5-10 minutes. The result will be recorded in your notes, and the notes can be requested by a court of law if need be.

You must notify the DVLA if you have laser treatment of both eyes, or if you have laser to your one good eye.

Normally the test is carried out by a computerised machine, a Humphrey. Occasionally the manual test has to be used, a Goldman. Again, for each test you have to look at a central point, and have to press a buzzer each time you see the light.

See videos Goldmann 1.6mb or computerised Humphrey 600kb (windows media) or Quicktime (550kb)

You need to bring your reading or bi-focal glasses you have. (But always bring your distance and reading glasses to every eye clinic visit.)

Usually the test is advised at you previous consultation. It is one of the most important tests for glaucoma. If your side vision gets worse, you may need more drops to lower the eye pressure further. It is usually carried out before the NEXT appointment, to help the doctor advise you on the treatment that would be helpful.

The test determines whether or not you have lost sight from glaucoma and other conditions. Changes in the visual field help to determine if the sight is getting worse and the glaucoma is progressing (if it is progressing your eye needs a lower pressure).

Reduction in the mean deviation of Humphrey fields is significant, and is a very quick way to review the result.

Interesting technical notes    monitoring field changes

It is vital that you let the eye clinic know (see appointments) so an alternative appointment can be arranged, and the appointment offered to someone else, so you have to wait less time for the next appointment.

There are reports that Gabapentin can affect visual field. If you use Gabapentin, have an eye examination at your optometrist and ask for a visual field test. If the visual fields are reduced, let your GP know.

This drug often causes serious visual field loss. Speak to your neurologist...many patients are transfering to different drugs. See