RNFL, macular thicknesses, and ganglion cell parameters in all KC stages were lower than those in the control group. The RNFL, macular thickness, and ganglion cell parameters of the Grade 1 KC group were most similar to those of the control group. The severity of irregular astigmatism at the same stages of KC had a significant effect on OCT measurements. It may therefore be beneficial to know the amount of change/deviation in OCT measurements in keratoconus patients and to report which parameters exceed the standards so that OCT can be used to correlate the stage of keratoconus with the extent of the ocular disorder.

Our visual and OCT results suggest that both treatment modalities are effective with few side-effects. However, nepafenac is more efficacious than subtenon TA in terms of visual gain and its correlation with the reduction in CRT.

Background:The aim was to evaluate the effect of irregular astigmatism on the retinal nerve fibre layer (RNFL), macular thickness and ganglion cell analysis obtained by spectral domain optical coherence tomography (OCT) in eyes with keratoconus. Methods: Fifty-two eyes of 31 patients (20 females) with keratoconus that required correction of irregular astigmatism with rigid gas-permeable (RGP) contact lenses were included to this study. The average, superior, nasal, inferior, temporal and 12 clock hour sector's RNFL, ganglion cell and macular thickness analyses before and 30 minutes after RGP contact lens (Rose K2 -Menicon Z material, David Thomas Contact Lenses Ltd, Northampton, United Kingdom) wear were performed to all patients with Cirrus HD spectral domain optical coherence tomography. Results: The average thickness of the retinal nerve fibre layer, the thickness at the nasal quadrants and 1-2-3-4 o'clock hour sectors and mean signal strength were increased significantly by RGP contact lens wearing independent of the stage of keratoconus. Central sub-field thickness increased after correction with RGP contact lens (p = 0.037). After wearing RGP contact lenses, changes on ganglion cell analysis were not significant (all p values ≥ 0.111). Conclusions: OCT is a widely used device for retinal nerve fibre layer and macular thickness evaluation in patients with glaucoma and macular diseases. The study demonstrates that OCT parameters such as retinal nerve fibre layer, central sub-field thickness and mean signal strength are affected by irregular astigmatism. Correction of irregular astigmatism with RGP contact lenses should be recommended before analysing keratoconic eyes to obtain optimum results on OCT measurements.

XFS is related with thinner RNFL and GCC even in normal intraocular pressure values, similar optic disc parameters and visual field results. XFS may be an independent risk factor for glaucomatous optic nerve damage. So, further studies are needed to evaluate whether exfoliation itself is an independent risk factor for optic nerve damage.

In individuals who have a history of POAG in their first-degree relatives, OCT parameters including retinal nerve fibre layer and ganglion cell complex are significantly lower than the subjects without a family history. Retinal nerve fibre layer and ganglion cell complex thinning were detected in normal-looking discs. The importance of these findings remains uncertain. Prospective, controlled clinical trials with longer follow up are necessary to understand, whether or not those changes are an early indicator of glaucoma.