Combined three-dimensional spectral OCT/SLO topography and Microperimetry: steps toward achieving functional spectral OCT/SLO

To investigate the combination of 3D optical coherence tomography (OCT) retinal thickness measurements and superimposed scanning laser ophthalmoscopy (SLO) microperimetry obtained using a Spectral OCT/SLO and to test the correlation between retinal thickness and retinal sensitivity in retinal diseases grouped according to anatomic locations.

Patients with various retinal diseases and subjects with normal fundi underwent microperimetry testing and imaging with the Spectral OCT/SLO. Based on the Spectral OCT/SLO findings, the participants were divided into 4 groups: patients with retinal thickening due to the outer retina pathology (group I); patients with retinal thickening due to the cystic changes observed in the inner retina (group II); patients with macular neurosensory retina thinning associated with geographic atrophy or underlying subretinal cicatricial changes (group III), and subjects with unremarkable fundus appearance and normal appearing retina on Spectral OCT/SLO (group IV). The primary outcome was the correlation coefficient (r) between Spectral OCT/SLO-measured macular thickness and microperimetry values.

Correlations between retinal thickness and psychophysical thresholds were calculated for each patient, and these values were averaged within groups. The mean correlation values (Pearson product movement) were as follows: for group I (n = 21 eyes) r = 0.04; for group II (n = 24 eyes) r = -0.53; for group III (n = 16 eyes) r = 0.41, and for group IV (n = 15 eyes) r = 0.04.

The combination of 3D OCT images and superimposed SLO microperimetry obtained by Spectral OCT/SLO demonstrated that thickening due to cystic changes of the inner retinal layers or thinning of the neurosensory retina on OCT correlated most significantly with decreases in psychophysical threshold sensitivities.