Evaluation of lamina cribrosa and peripapillary vascular density in thyroid orbitopathy and effect of intravenous methylprednisolone therapy

Purpose To evaluate optic nerve head changes in patients with thyroid orbitopathy (TO) and investigate the effects of intravenous methylprednisolone (IV MTP) on these changes. Methods Eighty-two eyes of 41 patients with TO with and without dysthyroid optic neuropathy (DON) and 40 eyes of 40 healthy control subjects were included in the study. Lamina cribrosa thickness (LCT) and depth (LCD) measurements, peripapillary retinal nerve fibre layer thickness (RNFLT), and radial peripapillary capillary vascular density were measured using optical coherence tomography and optical coherence tomography angiography. Visual field examination and proptosis were evaluated. Patients with DON and active non-DON received IV MTP for 12 weeks, and the effect of this treatment was evaluated. Results Peripapillary vascular density decreased in patients with DON compared with the other groups (p < 0.001 for all); there was no difference in the total, superior hemi-sector, and inferior hemi-sector of the RNFLT between the groups. LCT was decreased in the TO group (p < 0.001). After IV MTP treatment, the LCT and best-corrected visual acuity were increased. Thyroid-stimulating hormone receptor antibody levels, intraocular pressure, the superior hemi-sector of the RNFLT, and proptosis were decreased compared with the control subjects (p = 0.012, p = 0.008, p = 0.043, and p < 0.001, respectively). Conclusions The RNFLT may not always increase in DON. Lamina cribrosa morphology may change in patients with TO. IV MTP therapy has a positive effect on the LCT but not on radial peripapillary capillary vascular density or LCD.