To study the role of optical coherence tomography (OCT) as a progression marker in patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD).Methods
We studied 36 eyes of 18 patients meeting criteria for AD (6 patients with mild AD, 7 patients with moderate AD and 5 patients with severe AD), and 21 eyes of 42 patients meeting criteria for MCI. In these two groups, we evaluated cognitive impairment through the Mini-Mental State Examination (MMSE), the verbal fluency test (VFT) and the clock test (CT) and we measured peripapillary retinal nerve fiber layer (RNFL) thickness, and macular volume and thickness using OCT.Results
There is a significant correlation between the decrease in peripapillary RNFL thickness, macular volume and macular thickness and the severity of the cognitive impairment measured by the three neuro-psychological tests (p=0.00).Conclusion
The reduction in peripapillary and macular thickness and macular volume is related to the severity of cognitive impairment. Thus, OCT can be used for the diagnosis of AD and MCI (especially in the diagnosis of early- stage AD), as well as to evaluate cognitive impairment progression.