Graefe’s Arch Clin Exp Ophthalmol
2001) 239:556–561
(
C L I N I C A L I N V E S T I G AT I O N
DOI 10.1007/s004170100308
Bernhild Heinemann-Vernaleken Comparison of different high resolution
Anja M. Palmowski
Reiner Allgayer
Klaus W. Ruprecht
multifocal electroretinogram recordings
in patients with age-related maculopathy
Abstract Aim: to compare two dif-
ferent resolutions of multifocal elec-
troretinogram recordings (MF-ERG)
in patients with age-related macular
degeneration (AMD). Patients and
methods: in 20 eyes (14 patients)
with early or late stages of AMD,
Sixteen of 20 eyes also showed focal
Received: 1 February 2001
Revised: 30 April 2001
retinal dysfunction at both resolu-
tions. In one case, the high resolution
MF-ERGs could detect functional
deficits that could not be seen with
the lower resolution. However, due to
a reduced signal-to-noise ratio three
Accepted: 30 April 2001
Published online: 24 July 2001
©
Springer-Verlag 2001
MF-ERGs of 8 min duration were re- high resolution recordings could not
corded using a low and a high resolu- be analysed. Conclusion: high resolu-
tion. The central 50º of the retina
tion MF-ERG seems more sensitive
were stimulated by 103 as well as by than low resolution MF-ERG. How-
2
41 stimulus elements. Results were
ever, the low resolution (103) MF-
ERG is recommended for routine ap-
plication in the clinic because of its
better signal-to-noise ratio.
Supported by Deutsche Forschungs-
gemeinschaft PA 609/2-2
compared with one another and with
an age-matched control group. Re-
sults: when response averages of
equal eccentricity were analysed, am-
plitudes of the MF-ERG differed sig- Keywords Multifocal
nificantly from normal within the
central 40°. This held true for both
B. Heinemann-Vernaleken (
A.M. Palmowski · R. Allgayer
K.W. Ruprecht
)
✉
Universitäts-Augenklinik,
Kirrbergerstrasse 1,
electroretinogram · Age-related
macular degeneration · Stimulus
6
6421 Homburg/Saar, Germany
e-mail: aubhei@med-rz.uni-sb.de
low (103) and high (241) resolutions. resolution
vascularisation (CNV) membranes. It is most often fol-
lowed by a serious vision impairment.
Introduction
To follow patients during the course of therapy and to
enable an early diagnosis of AMD, new examination
methods may be helpful. This is all the more important
as parafoveal retinal function, which may be crucial to
retain some reading ability, cannot be monitored effec-
tively by testing visual acuity alone. The multifocal elec-
troretinogram (MF-ERG) presents itself as a non-inva-
sive, high resolution examination technique for assess-
ment of retinal function.
Its applicability to detect focal retinal dysfunction in
AMD has been shown [1, 5]. Since the optimal resolu-
tion for multifocal ERG recordings in AMD is not yet
clear, we have compared two different resolution MF-
ERGs in patients with AMD.
Age-related macular degeneration (AMD) is a disease of
the elderly. In industrial countries it is the major cause of
blindness in the population over 50 years old. Almost
one third (27.9%) of the population over 74 years is af-
fected [4].
One of the major findings in AMD is an accumulation
of metabolic products in the retinal pigment epithelium
(
RPE), following phagocytosis of the outer segments of
the photoreceptor membranes. These products that con-
tain fatty acids also accumulate in Bruch’s membrane,
which thickens and hinders diffusion [6]. When a larger
quantity of this material is collected in the subepithelial
space it forms the so-called drusen [6]. This occurs
mostly in the macular area. The exsudative form of
AMD is characterised by the formation of choroidal neo-