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Retinal dysfunction in a presymptomatic patient with Huntington's disease.
Jonelle Knapp1, Dean A VanNasdale2, Keith Ramsey2
1The Ohio State University College of Optometry, 338 West 10th Avenue, Columbus, OH, 43210, USA. jonknapp01@gmail.com.
Documenta Ophthalmologica. Advances in Ophthalmology
|April 26, 2018
Summary
Early retinal dysfunction was detected in a presymptomatic Huntington's disease (HD) patient using electroretinography (ERG) and multifocal ERG (mfERG). These findings suggest potential for early detection of neural dysfunction before overt symptoms appear.
Area of Science:
- Neuroscience
- Ophthalmology
- Genetics
Background:
- Huntington's disease (HD) is a neurodegenerative disorder with known retinal abnormalities.
- Previous research has not evaluated retinal structure and function in presymptomatic HD patients.
Observation:
- A 25-year-old male, genetically positive for HD but presymptomatic, underwent comprehensive ocular testing.
- Testing included visual electrophysiology (ERG, mfERG), visual field, SD-OCT, and fundus photography.
Findings:
- Electrophysiology revealed rod and cone functional anomalies, with subnormal ERG amplitudes and attenuated mfERG P1 amplitudes.
- SD-OCT and fundus photography were unremarkable; visual field showed a mild defect in one eye.
- Retinal dysfunction was detected despite the absence of motor, cognitive, or psychiatric symptoms.
Implications:
- ERG and mfERG may detect early neural dysfunction in presymptomatic HD patients.
- These electrophysiological tests could offer a method for monitoring disease progression or treatment efficacy.
- Further research is needed to validate these findings in larger cohorts.
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