Retinal Amyloid Imaging for Screening Alzheimer's Disease.

BACKGROUND Cost-effective and noninvasive methods for in vivo imaging of amyloid deposition are needed to screen Alzheimer's disease (AD). Although retinal amyloid is a possible diagnostic marker of AD, there are very few studies on in vivo retinal amyloid imaging. OBJECTIVE To examine the usefulness of in vivo imaging of retinal amyloid in AD patients. METHODS To examine amyloid deposition, 30 Japanese subjects (10 normal control (NC), 7 with mild cognitive impairment (MCI), and 13 with AD) underwent a complete ophthalmic examination, including fundus imaging by scanning laser ophthalmoscopy before and after oral curcumin intake. RESULTS Retinal amyloid deposition was greater in AD than in NC subjects (*p < 0.05) while MCI showed a slight but insignificant increase of retinal amyloid deposition relative to NC subjects. Retinal amyloid deposition was correlated with whole gray matter atrophy (r = 0.51, *p < 0.05) but not with the cognitive score of the Mini-Mental State Examination, nor with medial temporal lobe atrophy. CONCLUSION The present noninvasive in vivo detection of retinal amyloid deposition is useful for screening AD patients.