Abstract
Purpose:
To explore whether retinal imaging can be used to detect ocular changes in amnestic mild cognitive impairment (aMCI), which is considered a pre-clinical state to Alzheimer’s Disease dementia (DAT).
Methods:
We recruited seventeen aMCI subjects from Northwestern’s Alzheimer's Disease Center (NADC) clinical core registry. These aMCI subjects were age, sex, and race matched with cognitively normal control subjects and neuropsychological test scores were available for all subjects. Each subject underwent an ophthalmologic clinical exam including best corrected visual acuity and refraction, Pelli Robson contrast sensitivity, intra-ocular pressure measurement, and color vision testing. Finally, ocular imaging was performed including optical coherence tomography of the macula and optic nerve, fundus photography, and fundus autofluorescence imaging.
Results:
Mean age for controls and aMCI subjects was 75 (range 62-90). Five in each group were African American and the remainder Caucasian. Preliminary analysis using two-tailed Student’s t-test showed a trend for decreased contrast sensitivity in MCI patients (p-values of 0.17 and 0.13 OD and OS respectively). Retinal nerve fiber layer thickness similarly showed a trend in MCI patients (p-values of 0.28 and 0.25 OD and OS). In the macula, there were similar trends of thinning in MCI patients’ inner-nasal, inner-superior, and center quadrants with p-values of 0.16, 0.14, and 0.21, respectively.
Conclusions:
Our preliminary data suggest a trend for decreased contrast sensitivity along with thinning in the temporal and superior quadrants of the optic nerve and corresponding nasal quadrants of the macula on OCT. Though the differences did not reach statistical significance, we are undertaking further analyses controlling for age and sex, which can affect ocular measurements. These results will be completed by the time of the ARVO meeting.