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Updated: Jul 9, 2026
09:17
Using Retinal Imaging to Study Dementia
Published on: November 6, 2017
Retinal sublayer changes in cases with Alzheimer's disease and depression
Mohammad Reza Talebnejad1, Zahra Zia2, Vahid Reza Ostovan3
1Poostchi Ophthalmology Research Center, Department of Ophthalmology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
Summary
Alzheimer's disease (AD) and depression impact elderly vision, causing retinal thinning. AD showed more significant effects on inner retinal layers than depression, impacting diagnosis.
Area of Science:
- Ophthalmology
- Neurology
- Geriatrics
Background:
- Alzheimer's disease (AD) and depression are common in the elderly.
- Both conditions can affect the visual pathway's structure and function.
- Optical Coherence Tomography (OCT) allows detailed imaging of the optic nerve head and macula.
Purpose of the Study:
- To investigate the simultaneous effects of AD and depression on optic nerve head and macular parameters.
- To utilize OCT imaging for precise measurement of retinal layers.
Main Methods:
- Cross-sectional study with 50 mild to moderate AD patients and 50 healthy controls (HCs).
- Participants completed the Patient Health Questionnaire-9 (PHQ-9) and Mini-Mental State Examination (MMSE).
- Ophthalmic examinations excluded individuals with refractive errors or ocular pathologies; peripapillary retinal nerve fiber layer (pRNFL) and macular layers were imaged using Heidelberg OCT.
Main Results:
- AD patients exhibited significant thinning in supra temporal and infra temporal pRNFL quadrants compared to HCs.
- Inner macular layers, including the ganglion cell layer (GCL) and inner plexiform layer (IPL), were significantly reduced in the AD group.
- Depression severity negatively correlated with GCL volume, and MMSE score was a stronger predictor of GCL volume than depression status, with a significant interaction between MMSE and depression.
Conclusions:
- Elderly individuals with AD and depression show altered inner retinal layer thickness, with AD having a more pronounced effect.
- These findings are crucial for early AD diagnosis and monitoring.
- Retinal changes may affect OCT-based glaucoma detection in patients with coexisting neuropsychiatric disorders, especially AD.
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