In order to test the hypothesis that in primary open angle glaucoma (POAG), an important cause of irreversible blindness, a spreading of neurodegeneration occurs through the brain, we performed multimodal MRI and subsequent whole-brain explorative voxelwise analyses in 13 advanced POAG patients and 12 age-matched normal controls (NC). Altered integrity (decreased fractional anisotropy or increased diffusivities) of white matter (WM) tracts was found not only along the visual pathway of POAG but also in nonvisual WM tracts (superior longitudinal fascicle, anterior thalamic radiation, corticospinal tract, middle cerebellar peduncle). POAG patients also showed brain atrophy in both visual cortex and other distant grey matter (GM) regions (frontoparietal cortex, hippocampi and cerebellar cortex), decreased functional connectivity (FC) in visual, working memory and dorsal attention networks and increased FC in visual and executive networks. In POAG, abnormalities in structure and FC within and outside visual system correlated with visual field parameters in the poorer performing eyes, thus emphasizing their clinical relevance. Altogether, this represents evidence that a vision disorder such as POAG can be considered a widespread neurodegenerative condition.

Blurred vision in keratoconjunctivitis sicca eyes could be the result of the loss of the glossy surface of the tear film because of changes in composition or thickness irregularities. Spatial-contrast sensitivity in keratoconjunctivitis sicca and normal control eyes was tested before and after a tear substitute. Three different groups of subjects were enrolled: one group of dry eyes with nonsignificant signs of epithelial disease (n = 12), the second group of dry eye positive with 1% Bengal rose staining of the cornea and of the conjunctiva (n = 18), and a third of normal eyes as control group (n = 15). In all the 45 eyes, spatial-contrast sensitivity was tested under the best correction by means of the Vistech Multivision Contrast Tester 8000 (Vistech Consultants, Dayton, OH, U.S.A.) before and 15 min after the instillation of a 0.4% Na-hyaluronate tear substitute without preservatives. A significant decrease of spatial-contrast sensitivity ranging from 35 to 70% was present in keratoconjunctivitis sicca eyes compared with a third group of age-matched normal eyes used as control. The spatial-contrast sensitivity was significantly lower also in the presence of preserved corneal surface. The addition of a tear substitute improved spatial contrast—sensitivity thresholds in all groups. Tear-film disease can affect the transfer function of modulation of the ocular surface.