Glial proliferation and atrophy: Two poles of optic disc in patients with retinitis pigmentosa

To clarify the difference of retinal nerve fiber layer (RNFL) thicknesses between patients with retinitis pigmentosa (RP) and normal subjects.

The study included right eyes of 30 patients with non-late-stage RP, which had a waxy pallor in OD, attenuation in retinal arterioles, and midperipheral bone spicule pigmentary changes. To compare the RNFL analysis with normal subjects, the right eyes of 30 age- and gender-matched healthy subjects were included as a control group.

There were no differences between the RP and control groups in terms of demographic and baseline characteristics (P > 0.05, for all). The mean temporal quadrant RNFL thickness was 102.9 ± 31.7 μm (43–222) in the RP group and 72.4 ± 11.8 μm (51–90) in the control group (P < 0.001). The mean nasal quadrant RNFL thickness was 57.6 ± 33.7 μm (21–140) in the RP and 75.0 ± 14.1 μm (56–132) in the control group (P < 0.001). There were no significant RNFL thickness differences between the groups in other sectors and globally (P > 0.05, for all). There was no significant correlation between temporal RNFL thickening and ageing (r = −0.136, P = 0.196) while there was a significant correlation between nasal RNFL thinning and ageing (r = −0.274, P = 0.047).

RNFL is thicker in temporal quadrants and thinner in nasal quadrants in non-late stage RP. Age-related decreases in RNFL thickness occurred earlier in the nasal quadrant and RNFL thickening in the temporal quadrant occurred earlier than this global thinning.