Abstract
Primary glaucoma is a disease causing the greatest number of vision-related problems. Accelerated death of retinal ganglion cells and their axons which comprise the optic nerve as well as their involvement in the pathological process of neuroglia which provides nutrition for the optic nerve are considered as the main components of the glaucomatous process. The latest clinical research methods such as scanning laser polarimetry and optical coherence tomography measure structural changes at different functional levels of the retina and the optic nerve. According to literature data, structural changes in progressive glaucomatous optic neuropathy occur prior to apparent functional and clinical manifestations of the disease. In optical coherence tomography of glaucomatous eyes a scan of the macula is recommended to be performed using the Fast Macular Thickness Map protocol; it allows detecting the additional information on the pathological process. However, in a significant number of patients primary open-angle glaucoma can be very difficult to diagnose, and the nature and localization of the damage to eye structure as well as visual functions in patients with glaucoma need to be clarified. Neurophysiological method – electroretinography – allows us to study the processes at different morphofunctional levels of the retina as well as to clarify the localization and nature of pathological changes in the above-mentioned structures and to control dynamics of changes in the structures of primary damage at various stages of the glaucomatous process.
The objective of the research was to study the relationship between abnormalities in neurophysiological processes in central and peripheral regions of the retina and clinical parameters in patients with different stages of primary open-angle glaucoma.
Materials and methods. Complex clinical and neurophysiological study of eyes of 186 patients (358 eyes) with primary open-angle glaucoma was performed at the Filatov Institute of Eye Diseases and Tissue Therapy of National Academy of Medical Sciences of Ukraine. The main group included 81 (51.92%) females and 75 (48.08%) males with different stages of the glaucomatous process. The average age of patients was 56.8±4.26 years. Neurophysiological method - electroretinography using a RETI-scan multifocal ERG system (Roland Consult, Wiesbaden, Germany) - was used to diagnose the pathological condition.
Results. The strongest correlation was observed between neurophysiological processes occurring in neurons of the macular area – cone of the outer photoreceptor cell layer of the retina and parameters of retinal light sensitivity as well as the visual field index. According to the obtained results in patients with pre-glaucoma there was a direct correlation between the bioelectrical activity of the macular cone and mean deviation of the differential light sensitivity of the retina (r=0.56, р=0.05); in patients with mild primary open-angle glaucoma there was an inverse correlation between the duration of latent periods of neurons in the macular area and the visual field index (r=-0.33, р=0.02); in patients with advanced primary open-angle glaucoma there was a direct correlation between the duration of latent period of macular cone and intraocular pressure (r=0.41, р=0.034). In patients with advanced primary open-angle glaucoma there was an inverse correlation between the duration of latent period of neurons of the retinal photoreceptor cell layer in the macular area and the visual field index (r=0.42, р<0.029) as well as an inverse correlation between the parameters of the bioelectrical activity of the retinal photoreceptor cell layer in the macular area and those of the intraocular pressure (r=- 0.69, р<0.0000024); a direct correlation between the parameters of latent period of the second-order neurons in the macular area and those of the intraocular pressure was also observed (r=0.47, р<0.009).
References
Pasechnikova NV, Rykov SA. Analysis of the state of ophthalmic care in Ukraine in 2006-2011. Oftalmol. zhurnal. 2012;6:131-139.
Zhaboedov GD, Skripnik RL, Petrenko OV, et al. Modern concepts of the diagnosis “glaucoma”, problems of interpretation of the intraocular pressure and risk factors in this pathology. Oftalmologiya. Vostochnaya Yevropa. 2013;4(19):7-14.
Zavgorodnyaya NV, Pasechnikova NV. Primary glaucoma. New look at an old problem. Zaporizhzhia – Odesa. 2010;185.
Nil Choplin T, Diana Landi S. Glaucoma. Logosfera. Moscow, 2011;354.
Stotska LM, Stotska LS. Peculiarities of activity of chromatic visual channels in different stages of primary glaucoma. Oftalmol. Zhurn. 2013;6:22-25.
Valladares AM, Amoros NP, Cortes AC, Morollon JP, Moreno IF.Validity of ganglion cell-inner plexiform layer thickness measurement in the diagnosis of preperimetric glaucoma:correlation with retinal nerve fiber layer thickness. Glaucoma Unit of Albacete, Albacete- Spain. 11th EGS Congress. Nice. 2014;133.
Kachan TV, Marchenko LN, Birich TA, Dalidovich AA, Mushtina TA, Verenich AM. Comparative evaluation of optical coherence tomography and scanning laser polarimetry in the diagnosis and monitoring of optic neuropathy in patients with glaucoma. Oftalmologiya. Vostochn. Yevropa. 2014;4(23):186-190.
Zeimer R. Quantitative detection of glaucomatous damage at the posterior pole by retinal thickness mapping. Ophthalmol. 1998;105(2):224-231.
Ojima T. Measurement of retinal nerve fiber layer thickness and macular volume for glaucoma detection using optical coherence tomography. Jpn. J. of Ophthalmol. 2007;51(3):197-203.
Shamshynova AM, Andreeva TM. Clinical physiology of vision. Moscow. 2006; 956.
Wu De Zheng, Liu Yan. Atlas of testing and clinical application for Roland Electrophysiological Instrument. Beigind science and technology. Press. China. 2006;5-19.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.