Abstract
Purpose:
To investigate the retinal pigment epithelium (RPE) and ganglion cell complex (GCC) change using FD-OCT in retinitis pigmentosa with various severity and their temporal change after more than 1 year follow up
Methods:
In a retrospectively designed cross-sectional study, 150 eyes of 150 patients with RP who had retained central vision (better than 20/100) were examined with Cirrus OCT(Carl Zeiss Meditec Inc) and Goldmann perimetry using test target ΙΙΙ4e . RPE atrophy area was measured from advanced RPE analysis and mean ganglion cell complex thickness was detected from ganglion cell analysis. En face image of preserved photoreceptor inner segment and outer segment junction was demonstrated with advanced visualization and the area was calculated using photoshop and Image J software. Preserved central visual field was also analysed as a area. Pearson correlation coefficients (ρ) was used to measure the association between data subsets.
Results:
A high correlation between mean GCC thickness and preserved IS/OS area was observed (Pearson correlation ρ=0.642, P<0.0001). Inverse correlation between RPE atrophy area and IS/OS area was observed (ρ=-0.249, P=0.001). RPE atrophy had a tendency to increase exponentially as IS/OS area decreases. Visual field area was related with IS/OS area (ρ=0.347, P=0.001), mean GCC thickness (ρ=0.251, P=0.002) and RPE atrophy (ρ=-0.211, P=0.009). IS/OS area was also correlated with LogMar visual acuity (ρ=-0.273, P=0.001) Sixty two patients were included in follow up group. IS/OS area and GCC thickness was correlated significantly (ρ=0.311, P=0.01).
Conclusions:
In RP patients, preserved IS/OS area is related with residual central visual acuity and visual field. Ganglion cell complex comprised of ganglion cell and inner plexiform layer thickness has a strong linear correlation with preserved IS/OS area. RPE atrophy tend to develop after photoreceptor IS/OS layer loss. In consecutive examination suggested also stable correlation between IS/OS area and GCC thickness. This study revealed GCC degeneration and RPE atrophy pattern as photoreceptor degeneration.
Keywords: 696 retinal degenerations: hereditary •
461 clinical (human) or epidemiologic studies: natural history •
550 imaging/image analysis: clinical