Table 1.
Studies evaluating retinal biomarkers in Alzheimer’s disease using optical coherence tomography. Optical coherence tomography (OCT), ganglion cell layer (GCL), Alzheimer’s disease (AD), mild cognitive impairment (MCI), subjective memory complaints (SMC), healthy controls (HC), normotensive glaucoma (NTG), retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), ganglion cell inner plexiform layer (GCIPL), Bruch’s membrane opening-minimum rim width (BMO-MRW), inner plexiform layer (IPL), outer nuclear layer (ONL), inner nuclear layer (INL), outer plexiform layer (OPL), lamina cribrosa (LC), magnetic resonance imaging (MRI), positron emission tomography (PET), computed tomography (CT). Significant results are showed as (%, p).
| Source | OCT Exam: Layers | Macular or GCL Results |
AD Biomarkers |
OCT Platform | Cross-Sectional | Subjects | Sample Size (Eyes) |
|---|---|---|---|---|---|---|---|
| Iseri et al. 2006 | RNFL and macula | Thinner (23%, p < 0.001) |
No | Zeiss Stratus | Yes | AD HC |
AD 28 eyes (n = 14) HC 30 eyes (n = 15) Age-matched |
| Moschos et al. 2012 | RNFL and macula | Thinner (7%, p = 0.034) |
No | Zeiss Stratus | Yes | AD HC |
AD (n = 30) HCs (n = 30) Age and sex matched |
| Marziani et al. 2013 | RNFL + GCL combined | Thinner (12.8%, p = 0.008) |
No | RTVue-100 and Heidelberg Spectralis | Yes | AD HC |
AD (n = 21) HC (n = 21) Age-matched |
| Garcia-Martin et al. 2014 | RNFL and macula | Mild AD had a significant decrease in RNFL (9.24%, p = 0.015), of some macular regions and in the total macular volume (9.34%, p = 0.024). |
No | Topcon 3D OCT-100 | Yes | Mild AD HC |
Mild AD (n = 20) HC (n = 28) Age-matched |
| Ascaso et al. 2014 | RNFL and macula | RNFL was thinner in -MCI vs. HC (8.5%, p = 0.001)-AD vs. MCI (24.8%, p = 0.001) -AD vs. HC (37.5%, p = 0.001) Macular volume in mm3: -HC had greater macular volume vs. AD (12.4%, p = 0.001) |
No | Zeiss Stratus | Yes | AD MCI HC |
AD (n = 18) MCI (n = 21) HC (n = 41) |
| Eraslan et al. 2015 | RNFL and GCL | -RNFL Thinner in AD and NTG vs. HC (8%, p = 0.004). -GCL (8.8%, p = 0.001) -No difference between AD and NTG. |
No | RTVue-100 | Yes | NTG AD HC |
NTG (n = 18) AD (n = 20) HC (n = 20) |
| Bayhan et al. 2015 | GCL and choroid | Reduced choroidal (12.1%, p = 0.01) and macular GCL (5.9%, p = 0.001) thicknesses in AD |
CT or MRI | Zeiss Stratus | Yes | AD HC |
AD (n = 31) HC (n = 30) Age matched |
| Cheung et al. 2015 | RNFL and GCIPL |
- AD had GCIPL thinning in all sectors (AVG 5.4%, p = 0.039) and RNFL in Superior quadrant vs. HC (6.5%, p = 0.001) -GCIPL reduction in MCI (5.1%, p = 0.009) |
CT or MRI | Zeiss Cirrus | Yes | MCI AD HC |
AD (n = 100) MCI (n = 41) HC (n = 123) |
| Pillai et al. 2016 | RNFL, macula GCL | No differences (p = 0.35 and p = 0.17) |
MRI | Zeiss Cirrus | Yes | AD MCI No AD Dementia Parkinson HC |
AD (n = 21) MCI (n = 21) no AD dementia (n = 20) PD (n = 20) HC (n = 34) Age-/sex-matched |
| Garcia Martin et al. 2016 | RNFL, GCL, INL, IPL, ONL, OPL | Thinner RNFL (5.6%, p = 0.004), GCL (2.8%, p = 0.04) and IPL (2.3%, p = 0.018) | No | Heidelberg Spectralis | Yes | AD HC |
AD (n = 150) HC (n = 75) Age-matched |
| Liu et al. 2016 | GCIPL | Thinner (2.1%, p = 0.003) |
Yes. MRI | Zeiss Cirrus | Yes | MCI AD HC |
MCI (n = 68) AD (n = 47) HC (n = 65) |
| Choi et al. 2016 | RNFL andGCIPL | -RNFL thinner in temporal sector (14.9%, p = 0.04). -GCIPL thinner in inferior sector (14.5%, p = 0.004). |
Yes | Zeiss cirrus | Yes | MCI AD HC |
AD (n = 42) MCI (n = 26) HC (n = 66) Age-matched, age as a covariate |
| Gimenéz Castejon et al. 2016 | Macula | Macular thickness reduction in MCI (5.7%, p = 0.05) vs. HC and in SMC vs. HC (4.9%, p = 0.05) | No | Zeiss cirrus | Yes | SMC MCI HC |
SMC n = 24 MCI n = 33 HC n = 25 |
| Snyder et al. 2016 | IPL | Thicker (5.8%, p = 0.029) |
Yes (florbetapir PET imaging) | Heidelberg Spectralis | Yes | SMC | SMC (n = 63) Age-matched, age as a covariate |
| Kwon et al. 2017 | RNFL and macula | RNFL average thinner in AD vs. MCI (7.8%, p = 0.011). Macular thickness was thinner from HC to MCI and to AD, but no significant. |
Yes (MRI) | Zeiss Cirrus | Yes | Gender and race unknown | AD (n = 15) MCI (n = 15) HC (n = 15) |
| Ferrari et al. 2017 | RNFL and GCIPL |
Thinning (6.4%, p = 0.023) (15.9%, p = 0.009) |
No | Heidelberg Spectralis | Yes | MCI AD HC |
AD (n = 39) MCI (n = 27) HC (n = 49) Age-matched, age as a covariate |
| Golzan et al. 2017 | RNFL and GCL | GCL thinner (5.2%, p = 0.02) No RNFL differences |
Yes (MRI, florbetapir PET imaging) | Heidelberg Spectralis | Yes | AD HC |
AD n = 73 HC n = 28 Age-matched, age as a covariate |
| Poroy et al. 2018 | RNFL and macula | Foveal thickness and volume were higher in AD (5.5%, p = 0.023). RNFL and other macular region not different. |
No | Zeiss Stratus | Yes | AD HC |
AD (n = 21) HC (n = 25) Age-matched |
| den Haan et al. 2018 | RNFL and macula | No differences | Yes (MRI, PET, CSF) | Heidelberg Spectralis | Yes | AD HC |
Early onset AD (n = 15) HC (n = 15) |
| Lad et al. 2018 | RNFL, GCIP | No differences | No | Heidelberg Spectralis | Yes | MCI AD HC |
MCI (n = 15) AD (n = 15) HC (n = 18) |
| Uchida et al. 2018 | ONL | No differences | Yes (MRI) | Zeiss Cirrus | Yes | AD MCI non-AD Dementia HC |
AD (n = 24) MCI (n = 22) non-AD dementia (n = 20) HC (n = 36) |
| Santos et al. 2018 | RNFL, GCL, OPL, ONL, IPL, INL | RNFL volume (p = 0.05), OPL temporal (p = 0.04), ONL (p = 0.026) and IPL volume (p = 0.020) and inferior thinner over a 27-month follow-up | Yes (florbetapir PET imaging, head CT) | Heidelberg Spectralis | No, 27 months | Preclinical AD HC |
Preclinical AD (n = 56) Age-matched |
| López de Eguileta et al. 2019 | RNFL, GCL, BMO-MRW, IPL, ONL, LC | RNFL (2.8%, p = 0.004), GCL (8.7%, p = 0.006), IPL (5.2%, p = 0.011) & ONL (7.9%, p = 0.010) showed significant thinning in eyes of patients with positive 11C-PiB PET/CT |
Yes (11C-labeled Pittsburgh Compound-B PET imaging, head CT) | Heidelberg Spectralis | Yes | MCI AD HC |
MCI (n =51) AD (n =12) HC (n = 63) |