98th Annual Meeting DOG 2000

V 197

The multifocal ERG in inherited degenerations of the retinal periphery

M. W. Seeliger

Multifocal electroretinography (MF-ERG), a method to ascertain the topographical distribution of retinal dysfunction, has become more widespread in recent years. An important feature is the availability of separate topographies for amplitude and implicit time.

In hereditary diseases of the peripheral retina, MF-ERG is diagnostically useful to discriminate disorders of the retinitis pigmentosa (RP) group from phenocopies, which can appear very similar but are commonly remains of an inflammatory episode and thus not progressing. Examples for that are cases of PPRCA (pigmented paravenous retino-choroidal atrophy) and of Epstein-Barr virus infection with retinal involvement. Many changes due to a systemic dysfunction (metabolic or drug-induced) start in a ring-shaped zone in the mid periphery.

Recent data suggest that it is furthermore possible to separate Usher syndrome I and II in not too advanced cases. It is shown that there are almost no implicit time delays in Usher I, whereas the delay in Usher II is close to that in non-syndromic RP.

Even if the diagnosis is known, it is possible and useful to monitor changes especially in the RP group (progression of peripheral loss of amplitude and implicit time delay) in order to support prognostic statements in individual patients.

Retinal Electrodiagnostics Research Group, Department II, University Eye Hospital, Schleichstraße 12-16, 72076 Tübingen