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Updated: Jul 3, 2026
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Multifocal Electroretinograms
Published on: December 4, 2011
Multifocal electroretinogram in mild to moderate essential hypertension
Fatih C Gundogan1, Zafer Isilak, Cuneyt Erdurman
1Department of Ophthalmology, Gulhane Military Medical School, Ankara, Turkey. fgundogan@yahoo.com
Summary
Essential hypertension causes local retinal dysfunction, with reduced P1 amplitudes in the central retina and Ring 3, and decreased N1 amplitude in Ring 1 compared to healthy individuals. These findings suggest retinal ischemia due to circulatory changes in hypertensive patients.
Area of Science:
- Ophthalmology
- Cardiology
- Medical Imaging
Background:
- Systemic arterial hypertension can affect ocular circulation.
- Early detection of retinal changes in hypertension is crucial for management.
Purpose of the Study:
- To investigate local retinal dysfunctions in mild to moderate essential hypertensive patients.
- To utilize multifocal electroretinogram (mfERG) for precise retinal function assessment.
Main Methods:
- mfERG was used to evaluate retinal function from the fovea to the peripheral 30 degrees.
- The study included 31 hypertensive patients (stages 1-2) and 31 healthy controls.
- Amplitudes and implicit times of mfERG responses (P1, N1) were compared between groups.
Main Results:
- Hypertensive patients showed significantly reduced P1 amplitudes in the central hexagon (CH) and Ring 3.
- A significant reduction in N1 amplitude was observed in Ring 1 of hypertensive patients.
- No significant differences were found in implicit times or between hypertension stages/retinopathy grades.
Conclusions:
- Hypertensive subjects exhibit localized retinal dysfunction compared to normotensive controls.
- These dysfunctions are likely linked to retinal ischemia caused by altered retinal and choroidal circulation.
- mfERG is a valuable tool for identifying subclinical retinal alterations in hypertension.
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