Retinal Structural Changes in Patients with Mild Cognitive Impairment

Abstract

Purpose: To assess retinal structural changes in persons with mild cognitive impairment (MCI) and to correlate these changes with the level of cognitive function. Material-methods: Using high-resolution spectral domain optical coherence tomography (SD-OCT) in MCI and control subjects we assess peripapillary Retinal Nerve Fiber Layer (RNFL) thickness loss, macular volume and macular thickness loss in all nine EDTRS (early treatment diabetic retinopathy study) areas, and macular Ganglion Cell Complex (GCC) (inner plexiform + ganglion cell layer + retinal nerve fiber) thickness loss. We assessed cognitive function using Mini Mental State Examination (MMSE) score. Results: In the study group there was found a statistically significant decrease in RNFL overall (Mann-Whitney test, p: 0.009) and temporal thickness (T-test, p: 0.013) and increased macular GCC Focal Volume Loss (FVL%) (Mann-Whitney test, p: 0.001) compared to the control group. In control group was also found a statistically significant positive correlation between retinal structural parameters and MMSE score. Conclusion: Our preliminary study results suggest that RNFL overall and temporal thickness in patients with MCI is significantly decreased compared to normal controls. GCC FVL% is significantly increased in patients with MCI compared to normal controls suggesting that there is macular focal loss of ganglion cells in MCI patients.