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The outer and inner retinal function in patients with multiple evanescent white dot syndrome
Jacob Y C Cheng1, Chi D Luu, Ian Y S Yeo
1Singapore National Eye Centre, Yong Loo Lin School of Medicine, National University of Singapore, Singapore. chengyen@singnet.com.sg
Clinical & Experimental Ophthalmology
|July 24, 2009
Summary
Multiple Evanescent White Dot Syndrome (MEWDS) patients show reduced oscillatory potentials (OPs) throughout the retina. Electrophysiology suggests inner retinal dysfunction precedes outer retinal involvement in MEWDS.
Area of Science:
- Ophthalmology
- Neuroscience
- Retinal Imaging
Background:
- Investigating retinal function in Multiple Evanescent White Dot Syndrome (MEWDS).
- Utilizing electroretinography (ERG), multifocal ERG (mfERG), and multifocal oscillatory potentials (mfOP) to assess retinal function.
- Examining both outer and inner retinal layers.
Observation:
- Reduced amplitudes in scotopic, maximal, photopic, and flicker ERG responses were observed in MEWDS patients.
- Markedly reduced dark- and light-adapted oscillatory potentials (OPs) were noted in affected eyes.
- Even in areas with normal mfERG, local OPs were reduced, indicating subtle dysfunction.
Findings:
- Oscillatory potentials (OPs) were found to be reduced throughout the retina in MEWDS.
- A residual area of 'normal' retinal function was identified using mfERG in some cases.
- Inner retinal dysfunction, assessed by OPs, was evident even in areas with seemingly normal mfERG responses.
Implications:
- Electrophysiological findings suggest MEWDS may initially affect the inner retina.
- Outer retinal function may be subsequently involved in the progression of MEWDS.
- This study highlights the utility of mfOP in detecting early functional changes in MEWDS.
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