An Investigation of Lateral Geniculate Nucleus Volume in Patients With Primary Open-Angle Glaucoma Using 7 Tesla Magnetic Resonance Imaging

Abstract

PURPOSE. To investigate lateral geniculate nucleus (LGN) volume of primary open-angle glaucoma (POAG) patients compared with age-and sex-matched controls using ultra-high field 7.0-T magnetic resonance imaging (MRI). METHODS. The study included 18 patients with POAG and 18 age-and sex-matched healthy volunteers. All subjects underwent imaging on a high-resolution 7.0-T MRI system. Bilateral LGNs were identified and manually delineated, and LGN volumes were compared. Peripapillary retinal nerve fiber layer (pRNFL) thickness, optic nerve head parameters (including optic disc size, rim area, and cup-to-disc ratio), and combined thickness of the ganglion cell layer and inner plexus layer (GC-IPL) were measured by Cirrus high-definition optical coherence tomography (OCT). Correlations between OCT parameters and LGN volume were investigated. RESULTS. Mean LGN volumes were significantly smaller in the POAG group than in the control group (right, glaucoma 83.97 mm(3) [SD +/- 26.65] versus control 106.12 mm(3) [SD +/- 24.32]; left, glaucoma 65.12 mm(3) [SD +/- 29.41] versus control 92.70 mm(3) [SD +/- 24.42], both P < 0.05). In the POAG group, average GC-IPL thickness was correlated with contralateral LGN volume (right LGN: r = 0.605, P = 0.008; left LGN: r = 0.471, P = 0.049). The correlation for right LGN volume remained significant after correction for multiple comparisons. However, there was no correlation between LGN volume and average pRNFL thickness or optic disc parameters in the POAG group. CONCLUSIONS. On high-resolution 7.0-T MRI, LGN volumes in POAG patients are significantly smaller than those of healthy subjects. Furthermore, in patients, LGN volume was found to be significantly correlated with GC-IPL thickness of the contralateral eye.