Multifocal electroretinography in patients with Stargardt's macular dystrophy

Chan

Survey of Ophthalmology

et al. 2007

Abstract. Multifocal electroretinography (mfERG) is an investigation that can simultaneously measure multiple electroretinographic responses at different retinal locations by cross-correlation techniques. mfERG therefore allows topographic mapping of retinal function in the central 40--50 of the retina. The strength of mfERG lies in its ability to provide objective assessment of the central retinal function at different retinal areas within a short duration of time. Since the introduction of mfERG in 1992, mfERG has been applied in a large variety of clinical settings. This article reviews the clinical applications of mfERG based on the currently available evidence. mfERG has been found to be useful in the assessment of localized retinal dysfunction caused by various acquired or hereditary retinal disorders. The use of mfERG also enabled clinicians to objectively monitor the treatment outcomes as the changes in visual functions might not be reflected by subjective methods of assessment. By changing the stimulus, recording, and analysis parameters, investigation of specific retinal electrophysiological components can be performed topographically. Further developments and consolidations of these parameters will likely broaden the use of mfERG in the clinical setting.

Section: Clinical Applications Of Mferg In Acquired Retinal Diseases mentioning

confidence: 99%

“…151,164,242 Purvin and Maturi performed mfERG in a patient who developed bilateral central scotoma after motor racing accident. 242 Clinical examination showed no evidence of pathology involving the optic disks and macula.…”

Section: Commotio Retinae and Traumatic Macular Hole After Blunt Traumamentioning

confidence: 99%

The Clinical Applications of Multifocal Electroretinography: A Systematic Review

Chan

Survey of Ophthalmology

et al. 2007

“…[13][14][15][16][17] Most previous studies have been performed under photopic conditions, which are thought to reflect mainly conemediated photoreceptor and bipolar function. 18,19 Although reduced amplitudes and delayed latency of the cone mfERG have been demonstrated with age [20][21][22] and in different stages of ARM [23][24][25][26] mainly with concentric ring averaging methods, there have been no studies identifying the functional impairment of rods.…”

Section: Introductionmentioning

confidence: 99%

Cone- and rod-mediated multifocal electroretinogram in early age-related maculopathy

Feigl

Brown

Lovie‐Kitchin

et al. 2004

Eye

Purpose To investigate the cone-and rodmediated multifocal electroretinograms (mfERG) in early age-related maculopathy (early ARM). Methods and subjects We investigated the cone-and rod-mediated mfERG in 17 eyes of 17 subjects with early ARM and 16 eyes of 16 age-matched control subjects with normal fundi. All subjects had a visual acuity of 6/12 or better. We divided the ARM subjects into two groups based on drusen size and retinal pigment epithelium abnormalitiesFa less advanced (ARM1) and a more advanced (ARM2) group. The mfERG data were compared to templates derived from the control group. We analysed the mfERG results for the central and peripheral fields (CP method) and the superior and inferior fields (SI method). Results While the mean cone results showed no statistically significant difference between the groups, the rods showed significantly delayed responses in the ARM1 group for the CP and the SI methods, but not in the ARM2 group, although there was a trend of longer latencies compared to the control group. Conclusion Our results show a functional impairment of the rods in early ARM subjects. As there is histopathological evidence showing earlier rod than cone impairment in early ARM, following the rod function with the mfERG might be helpful in diagnosis or for monitoring the progression of early ARM.

“…By multifocal stimulation and by the simultaneous measurement of all the focal responses, a strict correlation of any given signal to a corresponding field exists. [24][25][26] By using short m-sequences, the quality of each measurement cycle can be evaluated separately, and any cycle in which significant artefacts occur can be discarded. The SLOsystem we have employed is also a significant technical advance.…”

Section: Discussionmentioning

confidence: 99%

Scanning laser ophthalmoscope-evoked multifocal ERG (SLO-mfERG) in patients with macular holes and normal individuals

Rudolph

Kalpadakis

Bechmann

et al. 2003

Eye

Aims A scanning laser ophthalmoscope (SLO) has been used for multifocal electroretinography (mf ERG) measurements under simultaneous fundus monitoring. The aim of this study was to prove if the SLOmfERG measurement reflects reliably the clinically registered underlying disease, and to demonstrate the importance of its main advantage, fixation monitoring. Methods In all, 10 patients with macular hole stage II/III were included in the study, and 19 normal individuals served as the control group. The mf ERG device was combined with an SLO, which was used both as a stimulus and trigger unit as well as a fundusmonitoring system. Monitoring of the fundus was guaranteed by an infrared laser (780 nm). The stimulus matrix consisted of 61 hexagonal elements, covering 241 of the posterior pole. We examined both, patients with macular holes and healthy individuals. Results Compared to normal controls, patients with a macular hole (Gass stage III) showed a significant decrease in response density in the centre of the stimulus array, which correlated well with the morphological alteration observed by clinical examination. However, variation of response density of the central hexagonal area has been proved to be high. Conclusions SLO-mfERG is a feasible and reliable new technique to investigate macular function under simultaneous fundus control. The main advantage is that control of fixation can be used in order to obtain more reliable results that correlate well with visible fundus abnormalities such as in patients with macular holes. However, further investigations have to be performed in order to overcome sufficiently the problem of fixation instability.