Abstract
Purpose:
To evaluate the point-to-point relationship between local retinal sensitivity as assessed by Optos SLO microperimetry and retinal thickness and volume as determined by optical coherence tomography (OCT).
Methods:
Twenty four eyes of twenty four subjects with various retinal diseases were enrolled in this IRB-approved prospective cross sectional study. Microperimetry and spectral domain optical coherence tomography (SD-OCT) were obtained on the study eye of all enrolled subjects using an Optos Spectral OCT/SLO (Optos plc, Dunfermline, UK). Microperimetry was performed with the using a standard 45 stimuli pattern spread over the central 12 degrees of the macula (foveal-centered), Goldmann III stimuli, and a 4-2-1 threshold strategy. The OCT-derived retinal thickness map was registered to the microperimetry data by the OCT instrument allowing point-to-point correlation between retinal sensitivity and OCT thickness. Correlation analysis was performed using a total of 1080 loci.
Results:
The mean age of the study cohort was 69 (SD; 13) years and 50 % were female. Retinal diseases in the study eyes included dry and wet age related macular degeneration, diabetic retinopathy, vein occlusions, macular telangiectasia and central serous chorioretinopathy. The mean baseline best-corrected (log MAR) visual acuity was 0.26 (Snellen ~ 20/30) and the mean (± SD) total retinal sensitivity was 13.70 (± 2.74, range: 6.0 - 16.90) dB. The log MAR visual acuity was significantly correlated with mean retinal sensitivity (r= -0.43, p=0.05), with an expected stronger correlation for foveal sensitivity (r= -0.74, p <0.001). Age was negatively correlated with mean retinal sensitivity (r= -0.42, p=0.05). The mean macular retinal thickness was 273.55 (± 32.31, range: 219 - 388) µm and the mean total retinal volume was 7.70 (± 0.92, range: 6.18 - 10.94) cubic mm. There was no significant correlation between the mean retinal sensitivity and mean retinal thickness (r=-0.06, p=0.79) or total retinal volume (r=-0.06, p=0.78). The point retinal sensitivity demonstrated a statistically significant, but weak correlation with corresponding point retinal thickness (r=-0.095, p=0.002).
Conclusions:
Local retinal sensitivity and retinal thickness are not strongly correlated, suggesting that microperimetry can provide independent, and potentially useful information regarding the effect disease on the status of the retina.
Keywords: 642 perimetry •
550 imaging/image analysis: clinical •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound)