Macular Thickness Measurements with Frequency Domain-OCT for Quantification of Retinal Neural Loss and its Correlation with Cognitive Impairment in Alzheimer's Disease.
To evaluate the ability of frequency domain optical coherence tomography (fd-OCT) to estimate retinal neural loss in eyes with Alzheimer's disease (AD). We also verified the existence of a correlation between AD-related cognitive impairment and macular and peripapillary retinal nerve fiber layer (RNFL) thickness measurements.



fd-OCT scans were obtained from 45 eyes of 24 patients with AD and 48 control eyes. Peripapillary RNFL, macular full-thickness and segmented inner macular thickness parameters were calculated. The inner macular parameters included macular retinal nerve fiber layer (mRNFL) thickness, ganglion cell layer (GCL) plus inner plexiform layer thickness (GCL+), and RNFL plus GCL+ thickness (GCL++). The Mini-Mental State Examination (MMSE) was used to assess cognition in all subjects. The two groups were compared and the relationship between MMSE scores and fd-OCT measurements was verified.



Average, superior and inferior quadrant RNFL thickness parameters and all but one of the nine full-thickness macular measurements were significantly reduced in AD patients compared to controls. The segmented layers, GCL+ and GCL++ were significantly reduced in AD eyes. A significant correlation was found between most fd-OCT parameters (especially macular thickness measurements) and MMSE scores.



Most fd-OCT peripapillary RNFL and macular full-thickness and segmented inner retinal layers parameters were reduced in AD eyes compared to controls. Moreover, neuronal loss, especially as reflected in macular parameters, correlated well with cognitive impairment in AD. Our results suggest that fd-OCT could be a potentially useful diagnostic tool in the evaluation and follow-up of AD patients.
Department of Ophtalmology, School of Medicine, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.|Juiz de Fora Eye Hospital, Minas Gerais, Juiz de Fora, Minas Gerais, Brazil.
Leonardo Provetti
LP
Cunha
Department of Ophtalmology, School of Medicine, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
Luciana Cheker
LC
Lopes
Juiz de Fora Eye Hospital, Minas Gerais, Juiz de Fora, Minas Gerais, Brazil.
Luciana Virgínia Ferreira
LV
Costa-Cunha
Juiz de Fora Eye Hospital, Minas Gerais, Juiz de Fora, Minas Gerais, Brazil.
Carolina Ferreira
CF
Costa
Department of Neurology, School of Medicine, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
Leopoldo Antônio
LA
Pires
Department of Neurology, School of Medicine, Federal University of Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
Ana Laura Maciel
AL
Almeida
Division of Ophtalmology, University of São Paulo Medical School, São Paulo, São Paulo, Brazil.
Mário Luiz Ribeiro
ML
Monteiro
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000473:pathology*; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000473:pathology*; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000379:methods*