COMPARATIVE ANALYSIS OF TONOMETRY METHODS

The principles of glaucoma diagnostics are based on the triad of symptoms -the excess of IOP over the tolerant level, changes in the visual field, primarily in the Bjerrum zone, and also on glaucomatous excavation of the optic nerve head. It should be recognized that the IOP level is the only proven risk factor for the progression of glaucomatous optic nerve atrophy and, at the same time, the only factor that we can influence. That is why the determination of IOP is of great importance in diagnosis and is the basis for evaluating the effectiveness of glaucoma treatment.Keywords: IOP (intraocular pressure), tonometry, glaucoma, primary open-angle glaucoma, glaucomatous optic neuropathy, tonometer, pneumotonometer

Early intervention and lifelong treatment with GLP1 receptor agonist liraglutide in a Wolfram Syndrome rat model with an emphasis on visual neurodegeneration, sensorineural hearing loss and diabetic phenotype

BackgroundWolfram syndrome (WS), also known as a DIDMOAD (Diabetes Insipidus, early-onset Diabetes Mellitus, Optic nerve Atrophy and Deafness) is a rare autosomal disorder caused by mutations in the Wolframin1 ( WFS1 ) gene. Previous studies revealed that glucagonlike peptide-1 receptor agonist (GLP1 RA) anti-diabetic drugs are effective in delaying and restoring glucose control in WS animal models and patients. The GLP1 RA liraglutide has also been shown to have neuroprotective properties in aged WS rats, reducing neuroinflammation, retinal ganglion cell death and optic nerve degeneration. WS is an early-onset, chronical condition and, therefore, early diagnosis and lifelong pharmacological treatment is the best solution to control disease progression in WS patients. Hence, the aim of this study was to evaluate the efficacy of the long-term liraglutide treatment on progression of WS symptoms. For this purpose, 2-month-old WS rats were treated with liraglutide (0.4mg/kg/day) up to the age of 18 months and changes in diabetes markers, visual acuity, hearing sensitivity were monitored in vivo over the course of the 16-month treatment period. ResultsEarly and chronic (16-month) intervention with the GLP-1 RA liraglutide delayed the development of glucose intolerance in WS rats. At the end of the experiment, 91% of saline- and 55% of liraglutide-treated WS rats needed daily insulin supplementation. Liraglutide administration was effective in maintaining visual acuity in WS rats by stalling the progression of cataract, degeneration of retinal ganglion cells and of optic nerve atrophy. Prolonged liraglutide therapy could not prevent sensorineural hearing loss at low frequencies. ConclusionThe rat model of WS used in this study is an excellent predictive model for preclinical trials as it closely recapitulates the relative onset and severity of the main symptoms of WS observed in human patients. We found that a 16-month treatment with GLP1 receptor agonist liraglutide delays or prevents the onset of diabetes and protects against vision loss in a rat model of Wolfram syndrome. Therefore, early diagnosis and prophylactic treatment with the GLP-1R agonist liraglutide may also prove to be a promising treatment option for Wolfram syndrome patients by increasing the quality of life of WS patients.

Genetic Spectrum and Characteristics of Hereditary Optic Neuropathy in Taiwan

Hereditary optic neuropathy (HON) is a group of genetically heterogeneous diseases that cause optic nerve atrophy and lead to substantial visual impairment. HON may present with optic nerve atrophy only or in association with various systemic abnormalities. Although a genetic survey is indispensable for diagnosing HON, conventional sequencing techniques could render its diagnosis challenging. In this study, we attempted to explore the genetic background of patients with HON in Taiwan through capture-based next-generation sequencing targeting 52 HON-related genes. In total, 57 patients from 48 families were recruited, with 6 patients diagnosed as having Leber hereditary optic neuropathy through initial screening for three common variants (m.3460G>A, m.11778G>A, m.14484T>C). Disease-causing genotypes were identified in 14 (33.3%) probands, and OPA1 variants were the most prevalent cause of autosomal HON. Exposure to medications such as ethambutol could trigger an attack of autosomal dominant optic atrophy. WFS1 variants were identified in three probands with variable clinical features in our cohort. Hearing impairment could occur in patients with OPA1 or WFS1 variants. This is the first comprehensive study investigating the genetic characteristics of HON in Taiwan, especially for autosomal HON. Our results could provide useful information for clinical diagnosis and genetic counseling in this field.

Neuritis of the optic nerve

At present, the problem of treating optic neuritis is becoming increasingly relevant due to growing incidence of this pathology among the young, significantly affecting their quality of life. High rate of disability outcomes (28%) connected with the development of optic nerve atrophy leading to irreversible changes in the visual functions accounts for high social value of this disease.The development of optic neuritis is known to happen very quickly in some cases, and in this regard all the performed methods of treatment should be urgent, aimed at increasing the treatment efficiency and preventing the irreversible complications due to the late and sometimes incorrect diagnosis.There are currently no reasonably effective treatments of optic nerve neuritis because generally, the therapy is etiopathogenesis-targeted, depending on the revealed cause of the disease, which in practice can rarely be established.The article reviews various methods of conservative and surgical treatment of optic neuritis and describes our experience of employing a drainage surgery technique with the use of allogeneic spongy biomaterial commonly used for complicated glaucoma.

Microperimetry in the diagnosis of early stages glaucoma

Purpose. To increase the efficiency of diagnostics of glaucomatous process in the early stages using microperimetry. Materials and methods. We examined 15 patients (30 eyes) aged 43-71 years (average age 62 years) with the initial stage of POAG, the duration of the disease was 8-36 months. The control group consisted of 10 patients (20 eyes), somatically healthy individuals without concomitant ophthalmopathology. In addition to standard research methods, the following were additionally carried out: optical coherence tomography (OCT) of the optic nerve disk, macular OCT for analyzing the thickness of the ganglion cell complex, angio-OCT of the optic disc and macula, and microperimetry. Results. When conducting microperimetric studies, a decrease in the average threshold photosensitivity AvThr (20 (4.8-23.3)) and the index of macular preservation MI (23 (2.8-26.8)) in patients with POAG was found in comparison with the control group. During OCT of the optic disc and macula, no changes were recorded in both groups, and there was no decrease in peripapillary perfusion during angio-OCT of the optic disc. However, in patients with POAG, during angio-OCT in the macular area, attention is drawn to some of its expansion and deformation, which confirms the fact that the macular area is involved in the glaucomatous process, which affects the photosensitivity of the cells of the central retinal area. Conclusion. Thus, the decrease in the average threshold of sensitivity in patients with POAG revealed by microperimetry makes it possible to detect glaucoma in the early stages, as well as to assess the dynamics of the glaucomatous process, which in its turn increases the effectiveness of treatment of patients. Key words: glaucoma, glaucomatous process progression, computer perimetry, microperimetry, optic nerve atrophy.

The effectiveness of treatment of partial optic nerve atrophy in children

Purpose. To evaluate the effectiveness of early treatment in patients with partial optic nerve atrophy, nystagmus and albinism. Material and methods. A study of case histories and outpatient records of 265 patients with partial optic nerve atrophy was carried out. Among them, 219 children received a single course of treatment and 46 children received two or more courses of treatment at different periods of initiation of therapy. Results. After a single course of treatment, 54% of children had no dynamics of visual acuity. After regular complex treatment, visual acuity increased by 0.2 and higher in 58.3% of children at the beginning of treatment under 3 years of age. In cases of isolated lesions of the optic nerve and with a combination of partial atrophy of the optic nerve with nystagmus, an increase in visual acuity by 0.2 and higher was noted in 50% and 60%, respectively, at the start of treatment for children under 3 years of age. Conclusion. Treatment of partial atrophy of the optic nerve is effective in children with regular courses of therapy. An increase in visual acuity by 0.2 and higher was observed twice as often at the start of complex treatment up to 3 years. Key words: optic nerve atrophy, children, visual acuity

INFECTIOUS AND INFLAMMATORY COMPLICATIONSIN OPHTHALMOLOGYAMID COVID-19

Inflammatory complications of the organ of vision in the time of COVID-19 can be manifested as conjunctivitis, scleritis, episcleritis, keratitis, uveitis and optic neuritis. It is essential to collect anamnesis, examine the blood for the presence of COVID 19 and treat these patients with the help of infectious disease specialists. Correct diagnosis of inflammatory ocular complications in the presence of COVID 19 makes it possible to prevent ocular complications, such as: ulcers and corneal penetration; fusion and overgrowth of the pupil,which leadto secondary glaucoma; endoophthalmitis, panophthalmitis and optic nerve atrophy. Timely intensive medical care and adequate treatment of these complications lead to a decrease in disability in this category of patients.Keywords:Ophthalmology, COVID-19,complications, ulcers, endoophthalmitis, panophthalmitis, gastrointestinal tract, cavernous sinus thrombosis