The multifocal electroretinogram in central serous chorioretinopathy

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: Central Serous Chorioretinopathymentioning

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. Recently Hood et al 27 developed a mfERG protocol for isolating rod responses in humans and Holopigian et al 28,29 demonstrated the clinical use of this protocol in retinitis pigmentosa and progressive cone dystrophy.…”

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.

Graefe's Arch Clin Exp Ophthalmo

“…Therefore, in patients with unsteady fixation, implicit times are the most suitable parameters for diagnosis [17,22]. In addition, during the interpretation of the results, attention should be paid to those cases with unsteady fixation which would mask the real result [11].…”

Section: Discussionmentioning

confidence: 99%

Effects of unsteady fixation on multifocal electroretinogram (mfERG)

Chu

Chan

Leat

2006

These results suggest that mfERG amplitude is not substantially affected if fixation is maintained within the central stimulus hexagon. We conclude that, for patients with poor fixation, the accuracy of mfERG results may be difficult to interpret and the use of a fixation-monitoring system is desirable for ideal measurement. The depth of depression at the blind spot area may be another useful parameter to interpret the accuracy of mfERG results in patients with poor fixation.