Abstract
Purpose :
To determine if dementia is associated with biomarkers of impaired macular retinal perfusion, compromised retinal structure, and choroidal perfusion.
Methods :
We applied 6x6 mm macular swept-source optical coherence tomography angiography (SS-OCTA) (PLEX® Elite 9000; ZEISS, Dublin, CA) to measure retinal nerve fiber layer (RNFL) thickness, ganglion cell complex (GCC) thickness, outer retinal layer (ORL) thickness, deep retina vessel area density (VAD), vessel skeleton density (VSD), vessel diameter (VD), choriocapillaris (CC) thickness, CC flow deficits (CCFDs), mean choroidal thickness (MCT), and choroidal vascularity index (CVI) in the dementia group compared with the normal and mild cognitive impairment (MCI) groups.
RNFL, GCC, ORL, and choroidal slabs were first segmented by a nnUnet deep learning algorithm. CCFDs, CC thickness, CVI, VAD, VSD, and VD were then measured by previously published algorithms. RNFL, GCC, ORL thicknesses, and MCT were obtained based on the segmented slabs. Regional analyses were done in 2.5 and 5.0 mm circles, and 2.5-5.0 mm rim. Comparisons of all variables within three groups were analyzed by the two-sample t-test, respectively. All p-values were adjusted within groups. We also performed a global adjustment of all variables by controlling false discovery rate (FDR).
Results :
99 patients (39 dementia, 32 MCI, and 31 controls) were included. Mean and standard deviation of the age were balanced among the three groups (ANOVA P=0.7): 75.97±5.76, 74.47±6.09, and 74.79±7.85 in dementia, MCI, and normal groups. Compared to normal subjects, GCC thickness was significantly thinner and CCFDs were significantly higher in the dementia group (Fig 1). VAD, VSD, and VD were significantly lower (Fig 2). Meanwhile, ORL thickness, CC thickness, MCT, and CVI didn’t show any significance. MCI had only a significantly reduced VSD compared with the normal group (Fig 2). No significance could be identified after performing global adjustment for all the 10 variables in three regions with the three groups.
Conclusions :
In this small, cross-sectional sample, we found lower GCC thickness, higher CCFDs, and lower VAD, VSD, and VD in eyes with dementia compared with normal group suggesting dementia may have impaired retina perfusion, structure, and CC perfusion.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.