Morphologic changes in the anterior and posterior subregions of V1 and V2 and the V5/MT+ in patients with primary open-angle glaucoma

Abstract

The aim of this study was to investigate possible morphologic changes of the visual cortex in primary open-angle glaucoma (POAG) with varying severity. Twenty normal controls (NC), 19 mild (MP) and 17 severe (SP) POAG patients were recruited and scanned using magnetic resonance imaging. Multi-parameter morphologic analyses with regions of interest (V5/MT+, anterior and posterior subregions of V1 and V2) were used to assess the cortical changes among the three groups. Compared with the NC group, decreased cortical thickness was detected in the V5/MT+ area in the MP group and in all of the investigated visual areas except the posterior subregion of V1 in the SP group. Unexpectedly, cortical thinning of the posterior subregion of V2 was detected in the SP group compared with the NC and MP groups. For the other morphologic parameters, only gray matter volume in the posterior subregion of V2 and mean curvature in the V5/MT+ were significantly changed in the SP group. In addition, the clinical measurements were positively correlated with the cortical thickness of the V5/MT+ and the posterior subregion of V2. In conclusion, the V5/MT+ area is involved in early disruption of POAG and the cortical degeneration may be progressive and heterogeneous in different visual cortices. Early neuroprotective therapies on the retina and central visual system may help to preserve vision in patients with POAG.

Keywords: Cortical thickness; Primary open-angle glaucoma; Retinal nerve fiber layer; Shape analysis; Visual cortex; Visual field; Volume.