Comparative Characteristics of Corneal Confocal Microscopy after UV-A Cross-linking with Different Riboflavin Solutions in Experiment

Ophthalmology in Russia, Journal Year: 2024, Volume and Issue: 21(4), P. 802 - 808

Published: Dec. 24, 2024

Corneal cross-linking (CXL) has become the most common way of managing keratectasia. To date, Dresden protocol (G. Wollensak et al., 2003) acquired many modifications, in which composition applied agents or modes CXL procedure have been changed. This article presents results studying morphological changes rabbit cornea vivo after using riboflavin solutions different composition. Purpose : compare effect on corneal structure experimental animals by confocal microscopy with saline, dextran and hydroxypropylmethylcellulose. Material methods . The study was performed 20 eyes 15 rabbits, underwent standard (Epi-Off) 0.1 % 3 groups: first group saline used as a base, second — dextran, third 1.0 hydroxypropyl methylcellulose (HPMC). irradiation mode: mW/cm2, 30 minutes, wavelength 370 nm. condition evaluated at 3, 7, 14, 90 days CXL. Biomicroscopy were all Heidelberg Retinal Tomographer HRT-III (Heidelberg Engineering, Germany). Keratocyte density counted depth 120–160 μm central zone area 1 mm2. Statistical processing Statistica 6.1 Excel 2010 programmes. Results In biomicroscopy corneas showed postoperative epithelium stroma groups, 7 CXL, there decrease keratocyte density, due to apoptosis, observed predominantly anterior layers stroma. number keratocytes 192.5 ± 29.8 cells/mm2, 2 227.4 38.2 204.4 32.6 cells/mm2 against intact control 352.8 35.2 cells/mm2. There not statistically significant difference between groups. Conclusion lifetime demonstrated similar early period, accompanied loss subepithelial nerve fibres, development lacunar edema, apoptosis their mainly middle beginning repopulation fibre regeneration 30th day No signs endothelium damage detected. A comparative assessment greatest effectiveness techniques 0.1% HPMC can be given basis larger-scale clinical studies.

Language: Английский

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Dynamics of riboflavin level in aqueous humour of anterior chamber of experimental animals under standard stroma saturation by ultraviolet corneal cross-linking solutions

Russian Annals of Ophthalmology, Journal Year: 2016, Volume and Issue: 132(6), P. 29 - 29

Published: Jan. 1, 2016

To evaluate the dynamics of riboflavin changes in aqueous humour anterior chamber (AHAC) rabbits' eyes during standard ultraviolet (UV) cross-linking with account to area corneal debridement.Forty two rabbits were studied sequentially. The following solutions used for cornea saturation: IR - 0.1% isosmotic riboflavin, D Dextralink (0.1% 20% dextran), R 1.0% hydroxypropylmethylcellulose (HPMC). Each solution was evaluated 3 groups that differed diameter debridement: group 1 Epi-Off mm (IR-3, D-3, P-3), 2 6 (IR-6, D-6, R-6), and 9 (IR-9, D-9, R-9). Aqueous sampling (252 samples total) performed 10-minute intervals within a 60 minute period. Riboflavin levels measured by enzyme-linked immunoassay (ID-Vit microbiological test system; Immundiagnostik, Germany).Stable growth rates level AHAC (with maximum values reached at 30-40 min) observed R, regardless variant debridement. Moreover, throughout whole follow-up period debridement, provided relatively lower concentration as compared other solutions. At 30 minutes, when considered ready UV irradiation, ranged from 385±26.1 μg/l (D-9) 665±28 (R-9). In IR-9, IR-6, P-6, IR-3, P-3 found be same range starting 20 minutes. However, even sufficient or cannot guarantee safe effective cross-linking, since removed epithelium limits stroma can saturated while exposure is 8-10 mm.Safe efficient may only under saturation which turn depends greatly on debridement (should least 8-9 mm). A HPMC enables quick pronounced and, thus, procedure, including cases insufficient thickness.Цель оценка уровня рибофлавина во влаге передней камеры (ВПК) глаза экспериментальных животных в динамике при стандартном насыщении стромы роговицы растворами для ультрафиолетового (УФ) кросслинкинга зависимости от площади ее деэпителизации. Материал и методы. Исследования проведены последовательно на 42 кроликах. Для насыщения использовались растворы 0,1% изоосмотический (ИР), Декстралинк (0,1% рибофлавин с декстраном) (Д), 1% гидроксипропилметилцеллюлозой (ГПМЦ) (Р) диаметра деэпителизации роговицы: 1-я группа мм (ИР-3, Д-3, Р-3), 2-я (ИР-6, Д-6, Р-6), 3-я (ИР-9, Д-9, Р-9). После у всех течение ч интервалом 10 мин выполняли забор ВПК образца). Уровень определяли методом иммуноферментного анализа использованием тест-системы ID-Vit ('Immundiagnostik', Германия). Результаты. Установлена стабильная динамика роста вариантах эксперимента использовании растворов Д Р максимумом 30-40-й минуте. Средство все сроки наблюдения независимо удаленного эпителия обеспечивало меньшую концентрацию по сравнению ИР Р. На 30-й минуте исследования, когда роговица после считается готовой к УФ-облучению, содержание составляло 385±26,1 (Д-9) до (Р-9) мкг/л. В этих же пределах 20-й минуты регистрировался уровень фотосенсибилизатора группах ИР-9, ИР-6, Р-6, а также ИР-3, Р-3. Достаточная концентрация или роговице не может гарантировать выполнение качественного безопасного УФ-сшивания, поскольку площадь образует строме ограниченную зону, пропитанную рибофлавином, так как выполнении УФ-воздействию подвергается роговицы. Заключение. Безопасный эффективный стандартный УФ-кросслинкинг быть выполнен оптимальном рибофлавином преимущественно за счет достаточной (не менее мм). Раствор ГПМЦ обеспечивает быстрое значимое насыщение фотосенсибилизатором, что позволяет применять его процедуре том числе пациентов тонкой роговицей.Цель — («Immundiagnostik», 30—40-й 8—10 роговицей.

Language: Русский

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Local Antioxidant Status in Patients with Keratoconus after Ultraviolet Corneal Crosslinking

Ophthalmology in Russia, Journal Year: 2019, Volume and Issue: 16(1S), P. 74 - 78

Published: April 22, 2019

The article presents the study results of local antioxidant status in patients with progressive keratoconus and its dynamics after ultraviolet corneal crosslinking. Purpose : to oxidative activity tear cornea Patients methods . To assess level keratoconic according levels total (TAS) superoxide dismutase (SOD) fluid, as well their UV crosslinking were investigated. included 38 (38 eyes) stage I–II (classification Amsler), men — 24 (63.1 %), women 14 (36.9 %). standard group (S-CXL) was 20 eyes, pulsed accelerated protocol (I-CXL) 18 eyes. average age 32.4 ± 6.8 years. As a control group, 12 practically healthy individuals selected. time observation is before operation, on 3rd, 7th, 14th 30th days procedure. Results On basis conducted studies, it revealed that showed statistically significant decrease initial indicator TAS by 40 % amounted 1.68 0.21 mmol/l, compared people 2.82 0.15 mmol/l. SOD tears also lower 19 96.7 11.3 ng/ml, 119.1 16.5 ng/ml. use S-CXL caused during first 3 subsequent restoration level. pulse A-CXL this indicator, but end 1st month higher than preoperative better when using protocol. A treatment noted days, however, more collapse Conclusion data had shown antioxidative keratoconus. Ultraviolet causes maximum 3rd day procedure, from gradual recovery observed. contributed pronounced development cross-linking damage It manifests itself reduction method.

Language: Английский

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Traditional, unfairly forgotten, rarely used and promising drug delivery methods in ophthalmology: a clinical interpretation (Part 2)

Russian Ophthalmological Journal, Journal Year: 2019, Volume and Issue: 12(4), P. 83 - 91

Published: Dec. 12, 2019

The first part of the review [ROJ 2019; 12 (2): 83–95] presented a detailed description and clinical interpretation traditional methods drug delivery in ophthalmology, offered an analysis their advantages disadvantages. This paper is second review, which focuses on rarely used largely forgotten methods, as well targeted means to different structures eye.

Language: Английский

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Modern options for non-surgical correction of keratoconus

Russian Annals of Ophthalmology, Journal Year: 2020, Volume and Issue: 136(5), P. 289 - 289

Published: Jan. 1, 2020

The article reviews data on the so called non-surgical methods of keratoconus (KC) correction. combined approach to KC treatment entails three main tasks: prevention progression, optical correction induced refractive disorders, and structural repair. Measures taken accomplish first two tasks should be regarded as symptomatic treatment, while addressing last task requires pathogenetically oriented solutions. Corneal cross-linking disorders with rigid gas permeable (RGP) scleral contact lenses choice for keratoconus.В обзоре представлены данные о так называемых нехирургических методах коррекции кератоконуса (КК). Комплексный подход к корригирующему воздействию на это заболевание роговицы предполагает решение трех основных задач: профилактику прогрессирования, оптическую коррекцию индуцированных рефракционных нарушений и восстановление структурных изменений. Решение первых двух следует расценивать как симптоматическое, а последней — патогенетически ориентированное. Кросслинкинг коллагена с помощью жестких газопроницаемых склеральных контактных линз рассматривать в качестве «нехирургических» методов первого выбора симптоматической кератоконуса.

Language: Русский

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Topographic Localization of the Demarcation Line after UV Corneal Crosslinking in Progressive Keratoconus

Ophthalmology in Russia, Journal Year: 2018, Volume and Issue: 15(1), P. 32 - 37

Published: March 24, 2018

Purpose: To assess the topographic location of demarcation line in different areas cornea after standard corneal crosslinking. Patients and methods. 12 patients (15 eyes) with keratoconus stages 1–2 Amsler-Kruimerich classification were observed. UV cross-linking was performed all according to Dresden protocol 0.1% aqueous solution riboflavin. The underwent optical coherence tomography anterior segment eye on “DRI OCT Triton” (“Topcon”, Japan) line. Results. Demarcation revealed 1 month most cases (87%). Biomicroscopy showed that DL limited middle laers stroma from posterior one. stromal depth averaged 305.73 ± 41.08 μm (range 282–345 μm) at center, nasally — 215.16 35.5 160–289 temporally 205,23 32.81 190–276 μm). A significant difference localization central zone a 6 mm (p < 0.001) noted. Conclusion. (обычно) is one indicators photochemical process cross-linking. Optimal timing detection following collagen crosslinking 2 weeks 3 months. studied different; it deeper than peripheral ones.

Language: Английский

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Еfficacy of Combined Treatment of Epithelial and Endothelial Corneal Dystrophy Using Corneal Crosslinking and Automated Posterior Lamellar Keratoplasty

Ophthalmology in Russia, Journal Year: 2019, Volume and Issue: 16(1S), P. 102 - 107

Published: April 22, 2019

The purpose : to establish a combined approach the treatment of patients with epithelial and endothelial cornea dystrophy (EED) based on comparative study results one-step two-step methods. Patients included 75 (81 eyes) corneal EED, who underwent surgical at Ufa Eye Research Institute from 2011 2016. were divided into two groups — main group consisted 43 (46 eyes, 57 %) patients, first stage CC before second after 1–12 months automated posterior lamellar keratoplasty (APLK). In control group, isolated APLK was performed in 32 (35 patients. Results . After (1–10 days) an increase thickness due edema enhancement stroma observed I–III EED. 3 months, decrease recorded I-II stages disease (p < 0.05), 6 all EED compared 0.05). According optical coherence tomography (OCT), total both зфешутеы noted within 12 APLK: 667 ± 65 μm initially 594 31 μm, where there pronounced 787 56 612 67 μm. Conclusion Corneal cross-linking provides improvement cornea, manifested reducing its thickness. It allows delay implementation without deterioration I up 6–12 II–III 3–6 months.

Language: Английский

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Long-term results of corneal collagen crosslinking with ectatic forms of corneal dystrophy

Ophthalmology Reports, Journal Year: 2020, Volume and Issue: 12(4), P. 29 - 34

Published: March 5, 2020

Corneal collagen crosslinking is one of the most effective methods prophylactics and treatment progressive corneal ectasias. In literature, there are occasional data related to remote results concerning only common form ectasias keratoconus. published studies, no met efficacy in other forms ectasias, which now on rise, including secondary that became more frequent with refractive surgery. The number diagnosed cases pellucid marginal degeneration increased as well. literature shows comparative analysis this method various ectasias. aim investigation was evaluate based long-term for Materials methods. patients ectasia 6 years after surgery were analyzed. nosological structure study included keratoconus, degeneration, ectasia. group keratoconus 30 (30 eyes), eyes). performed by same specialist, during first or second year follow-up. Then changes state cornea visual functions monitored years. To assess efficacy, preoperative examination interim used. Results. all groups, an increase best corrected acuity, a decrease index asymmetry surface its power center However, obtained groups

Language: Английский

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Changes in precorneal tear film and ocular surface in keratoconic patients after corneal collagen cross-linking

Russian Annals of Ophthalmology, Journal Year: 2022, Volume and Issue: 138(3), P. 118 - 118

Published: Jan. 1, 2022

The article reviews the current available data on signs and symptoms of dry eye syndrome (DES) in patients with keratoconus (KC), describes clinical features DES KC morphological this type keratectasia that lead to manifestations «dry eye», highlights risk factors, consequences therapeutic measures, concomitant ophthalmological general somatic diseases contribute development KC.В настоящем обзоре представлены имеющиеся в современной литературе сведения о клинических симптомах и функциональных признаках синдрома сухого глаза (ССГ) при кератоконусе (КК). Перечислены клинические особенности ССГ КК морфологические данного вида кератэктазии, приводящие к клиническим проявлениям глаза. Освещены факторы риска, последствия лечебных мероприятий, сопутствующие офтальмологические общесоматические заболевания, способствующие развитию КК.

Language: Русский

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Crosslinking of the Bioplast plastic material as a means of increasing its biomechanical stability and the effectiveness of keratoplasty for corneal ulcers

Russian Ophthalmological Journal, Journal Year: 2021, Volume and Issue: 14(2), P. 36 - 41

Published: June 20, 2021

Purpose:to assess the effect of ultraviolet (UVA) crosslinking Bioplast plastic material (silicon-dried human cornea) on its biomechanical stability and effectiveness for keratoplasty in corneal ulcers. Material methods. To determine maximum rehydration time, 12 samples were incubated physiological solution (NaCl 0.9 %) hours monitored thickness using optical coherence tomography (OCT Spectralis, Heidelberg Engineering). After epithelium was scarified rehydrated corneas treated withof 0.1% riboflavin 30 minutes, after it 8 (experimental group) with UVA 30minutes (wavelength 370 nm, power 3 mW/cm 2 ) a UV-X device system (IROC AG, Switzerland). In control group (4 samples), no performed. The elastic-strength indicators experimental assessed by applying uniaxial tension deformation machine (Autograph AGS-H, Japan). examine patients (presented clinical examples)before subjected to crosslinking, set standard ophthalmic tests used. Results.Rehydration most intensive first three incubation, during which time tissue increased uniformly 50–55 μm/hour 700–710 μm, while further incubation showed significant additional fluid content cornea. strength indices elastic modulus significantly comparison group. Clinical examples demonstrate modified organ-preserving penetrating case perforatedcorneal ulcer. Conclusion. increases stability. data laboratory studies that may be an effective replacement native donor cornea urgent perforated

Language: Английский

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