An evaluation of the retinal nerve fiber layer thickness by scanning laserpolarimetry in individuals with dementia of the Alzheimer type

Purpose: To determine, using scanning laser polarimetry, whether or not the retinal nerve fiber layer (RNFL) is altered in dementia of the Alzheimer t ype (DAT), Methods: Thirty individuals with mild to moderate DAT and 30 healthy age-ma tched controls participated in the study. Fundus images were acquired with a Nerve Fiber Analyzer. RNFL thickness measurements were obtained under an ellipse located 1.75 disc diameter from the optic nerve head (ONH) center. Results: No differences in RNFL thickness were observed between DAT and hea lthy subjects. The regional distribution of RNFL thickness was similar betw een the two test groups, with the RNFL being thickest in the superior and i nferior retinal segments relative to the nasal and temporal regions, Conclusions: Our data indicate that the RNFL is not altered in DAT, at leas t in the earlier stages of the disease.