Assessment of inner retina layers thickness values in eyes with pituitary tumours before visual field defects occur

The purpose of this study was to evaluate macula, retinal nerve layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL) and macular nerve fibre layer (mNFL) thickness in patients with pituitary tumours who has normal visual field (VF).

Thirty-five eyes of 35 patients with pituitary tumours with normal VF and 41 eyes of 41-healthy subjects were underwent a complete ophthalmic examination. The spectral domain- optical coherence tomography (OCT) was used to measure macular and optic disc parameters. Layer-by-layer segmentation was done automatically by using the new software. Data analyses were performed by using SPSS for Windows, version 22.0.

Average of total macula thickness inner temporal (p: 0.006), outer temporal (p < 0.001), inner nasal (p: 0.03), outer nasal (<0.001) were significantly lower in pituitary tumour group than normal group. Average of RNFL (p:0.009), temporal (p: 0.001), superiotemporal (p:0.004) and inferiotemporal (p: 0.01) were significantly lower in pituitary tumour group than normal group. Average of central GCL (p: 0.01) and central NFL (p: 0.03) were significantly lower in pituitary tumour group than normal group. There was no statistically significant difference between the two groups in IPL averages.

Pituitary tumour patients with normal VF had reduced nasal and temporal section of the total macula, temporal RNFL, central mGCL and mNFL thicknesses, reflecting the corresponding to the anatomical substrate of the underlying pathology of chiasmal compression. This indicates that the presence of retinal thinning may be a sign of early detection of anterior visual pathway injury before VF loss becomes apparent.