Morphometric parameters of the optic nerve in patients with symptomatic ophthalmohypertension and secondary glaucoma associated with endocrine ophthalmopathy

Abstract

Objective. To analyze the morphometric parameters of the optic disc (OD) in patients with symptomatic ophthalmohypertension and secondary glaucoma associated with endocrine ophthalmopathy (EOP) according to the data of optical coherence tomography (OCT).Materials and methods. The morphometric parameters of OD and retinal nerve fiber layer (RNFL) thickness were assessed according to OCT data of 175 patients (350 eyes and orbits) with different forms and activity of EOP. 30 patients (60 eyes and orbits) were diagnosed with symptomatic ophthalmohypertension in active EOP stage. 30 patients (58 eyes and orbits) were diagnosed for the first time with secondary open-angle glaucoma associated with inactive EOP course. The control group comprised 30 somatically healthy individuals comparable in terms of age and sex without clinical EOP symptoms with normal ophthalmic tonus.Results. The patients with symptomatic ophthalmohypertension have revealed increased peripapillary RNFL thickness up to Me 95.5 [90; 101] μm (Mann-Whitney U=1107, p=0.0002), and increased neuro-retinal rim (NRR) area up to Me 1.65 [1.5; 1.9] mm² (Mann-Whitney test U=1425; p=0.04). The patients with secondary glaucoma associated with EOP have found a statistically significant decrease of the average RNFL thickness to Me 85[80;89] μm (by 8%) compared to the control group (Mann-Whitney U=553, p=0.00). The NRR area was statistically significantly reduced to Me 1.15 [1.0; 1.2] mm² (Mann-Whitney U=255.5; p=0.00).Conclusion. Patients with symptomatic ophthalmohypertension and active course of the processs detect signs of increased RNFL and NRR area thickness, which is related to retrobulbar fiber swelling and development of compressive ischemic optic neuropathy. Patients with secondary glaucoma are characterized by remodeling of OD parameters at the expense of decreased average peripapillary RNFL thickness, reduced NRR area and extended excavation, which is typical for glaucomatous optic neuropathy.