Volume of Lateral Geniculate Nucleus in Patients with Glaucoma in 7Tesla MRI

The aim of the study was to assess the volume of the lateral geniculate nucleus (LGN) in patients with open-angle glaucoma in 7Tesla MRI and to evaluate its relation to RNFL thickness and VF indices. Material and methods. The studied group consisted of 20 open-angle glaucoma patients with bilaterally the same stage of glaucoma (11 with early glaucoma and nine with advanced glaucoma) and nine healthy volunteers from the Department of Diagnostics and Microsurgery of Glaucoma, Medical University of Lublin, Poland. Circumpapillary RNFL-thickness measurements were performed using OCT in all patients and visual fields were performed in the glaucoma group. A 7Tesla MRI was performed to assess the volume of both lateral geniculate bodies. Results. The LGN volume varied significantly between groups from 122.1 +/- 14.4 mm(3)(right LGN) and 101.6 +/- 13.3 mm(3)(left LGN) in the control group to 80.2 +/- 17.7 mm(3)(right LGN) and 71.8 +/- 14.2 mm(3)(left LGN) in the advanced glaucoma group (right LGNp= 0.003, left LGNp= 0.018). However, volume values from early glaucoma: right LGN = 120.2 +/- 26.5 mm(3)and left LGN = 103.2 +/- 28.0 mm(3)differed significantly only from values from the advanced group (right LGNp= 0.006, left LGNp= 0.012), but not from controls (right LGNp= 0.998, left LGNp= 0.986). There were no significant correlations between visual field indices (MD (mean deviation) and VFI (visual field index)) and LGN volumes in both glaucoma groups. Significant correlations between mean RNFL (retinal nerve fiber layers) thickness and corresponding and contralateral LGN were observed for the control group (corresponding LGN:p= 0.064; contralateral LGN:p= 0.031) and early glaucoma (corresponding LGN:p= 0.017; contralateral LGN:p= 0.008), but not advanced glaucoma (corresponding LGN:p= 0.496; contralateral LGN:p= 0.258). Conclusions. The LGN volume decreases in the course of glaucoma. These changes are correlated with RNFL thickness in early stages of glaucoma and are not correlated with visual field indices.