rss
Br J Ophthalmol 2002;86:931-932 doi:10.1136/bjo.86.8.931
  • Letter

Tangent screens are still useful in the assessment of vigabatrin induced visual field defects

  1. JA Olson,
  2. AT Purdie,
  3. RJ Coleman
  1. The Eye Clinic, Aberdeen Royal Infirmary, Forester Hill, Aberdeen
  1. Correspondence to: Dr Olson; j.olson{at}arh.grampian.scot.nhs.uk
  • Accepted 13 February 2002

Vigabatrin induced constriction of peripheral visual fields was first reported in 1997.1 The potential mechanisms of vigabatrin induced peripheral field constriction are many,2 but in our opinion, not enough attention has been paid to the method and appropriateness of recording this constriction. Current recommendations for patients prescribed vigabatrin are that they are screened at regular intervals by automated perimetry. Automated perimetry cannot, however, differentiate between pathological and functional (non-physiological) constriction of the visual field. Furthermore, automated perimetry, although deceptively simple for the operator to perform, is notoriously laborious and fatiguing for the patient. Although several safeguards are built into automated perimetry, in the form of reliability indices, there are traps for the unwary. This is clearly demonstrated in the …

Register for free content

The full back archive is now available for all BMJ Journals. Institutional subscribers may access the entire archive as part of their subscription. Personal subscribers will also have access to all content when logged in. Non-subscribers who register have free access to all articles published before 2006 right back to volume 1 issue 1. Register here to access the free archive of all BMJ Journals.

Don't forget to sign up for content alerts so you keep up to date with all the articles as they are published.