Orientador: Silvana Artioli Schellini / Resumo: O objetivo do estudo foi avaliar a influência do diabetes experimental sobre a ultra-estrutura do endotélio corneal de ratos. O estudo foi prospectivo, utilizando 20 ratos da raça Wistar, com 3 meses de idade, divididos em: grupo controle (GC), contendo 10 ratos, e grupo diabético (GD), contendo 10 ratos. A indução do diabetes foi feita com injeção de Aloxana endovenosa 42 mg/kg de peso (M0), após o que os animais foram observados por 15 dias para confirmar a presença de diabetes grave (M1). Um mês após M1 (M2) e 12 meses após M1 (M3) os animais foram sacrificados, sendo removidos e preparados os olhos para avaliação à microscopia eletrônica de transmissão. Os animais do GD mostraram importante redução de peso, aumento da injestão hídrica e aumento da diurese em relação aos ratos do GC. Na avaliação morfológica observou-se nos animais do GC corpos densos e figuras de Mielina no M3. Os ratos do GD apresentaram as mesmas alterações encontradas no GC em M3, em maior intensidade, com alterações nucleares e citoplasmáticas, como mitocôndrias bastante alteradas na forma e tamanho, rarefação do citoplasma e aumento de vesículas. Os ratos do GD em M3 apresentaram mais alterações que os do GDM2. Conclui-se que o diabetes experimental causa dano ultra-estrutural no endotélio corneal de ratos e que as alterações são evolutivas. / Abstract: The objective of study was to make na assessment of experimental diabetes influence on of rats corneal endothelium ultra-structure. The study was prospective, using 20 Wistar 3-month-old rats, divided (by draw) into groups: control group (GC), with 10 rats, and diabetic group (GD), with 10 rats. The diabetes induction was made by means of intravenous injection of Aloxan 42 mg/Kg weigth. After the diabetes induction (M1), the animals had been observed for 15 days, and then, 1 month after M1 (M2) and 12 months after M1 (M3) to confirm the diagnosis of severe diabetes. At experimental moments M2 and M3, the animals eyes enucleation and preparation were carried out for assessment trough transmission eletronic microscopy. GD animals had shown significant reduction of weigth, increasing of hydric and nourishing injection and increasing of diuresis in relation to GC rats. In the morphological assessment, dense bodies and Myelin figures were observed in M3 GC animals. GC rats had presented the same alterations found in GC animals in M3, in major intensity, beyond mitochondrias rather modified in their form and size, cytoplasm rarefaction, vesicles increasing and nuclear alterations. It is concluded that experimental diabets causes ultra-structural of rats corneal endothelium. / Mestre

Made available in DSpace on 2014-06-11T19:23:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2002Bitstream added on 2014-06-13T19:09:41Z : No. of bitstreams: 1 martins_lc_me_botfm.pdf: 1919468 bytes, checksum: d4a42d395d3517a07ebafa18c26a4e02 (MD5) / O objetivo do estudo foi avaliar a influência do diabetes experimental sobre a ultra-estrutura do endotélio corneal de ratos. O estudo foi prospectivo, utilizando 20 ratos da raça Wistar, com 3 meses de idade, divididos em: grupo controle (GC), contendo 10 ratos, e grupo diabético (GD), contendo 10 ratos. A indução do diabetes foi feita com injeção de Aloxana endovenosa 42 mg/kg de peso (M0), após o que os animais foram observados por 15 dias para confirmar a presença de diabetes grave (M1). Um mês após M1 (M2) e 12 meses após M1 (M3) os animais foram sacrificados, sendo removidos e preparados os olhos para avaliação à microscopia eletrônica de transmissão. Os animais do GD mostraram importante redução de peso, aumento da injestão hídrica e aumento da diurese em relação aos ratos do GC. Na avaliação morfológica observou-se nos animais do GC corpos densos e figuras de Mielina no M3. Os ratos do GD apresentaram as mesmas alterações encontradas no GC em M3, em maior intensidade, com alterações nucleares e citoplasmáticas, como mitocôndrias bastante alteradas na forma e tamanho, rarefação do citoplasma e aumento de vesículas. Os ratos do GD em M3 apresentaram mais alterações que os do GDM2. Conclui-se que o diabetes experimental causa dano ultra-estrutural no endotélio corneal de ratos e que as alterações são evolutivas. / The objective of study was to make na assessment of experimental diabetes influence on of rats corneal endothelium ultra-structure. The study was prospective, using 20 Wistar 3-month-old rats, divided (by draw) into groups: control group (GC), with 10 rats, and diabetic group (GD), with 10 rats. The diabetes induction was made by means of intravenous injection of Aloxan 42 mg/Kg weigth. After the diabetes induction (M1), the animals had been observed for 15 days, and then, 1 month after M1 (M2) and 12 months after M1 (M3) to confirm the diagnosis of severe diabetes. At experimental moments M2 and M3, the animals eyes enucleation and preparation were carried out for assessment trough transmission eletronic microscopy. GD animals had shown significant reduction of weigth, increasing of hydric and nourishing injection and increasing of diuresis in relation to GC rats. In the morphological assessment, dense bodies and Myelin figures were observed in M3 GC animals. GC rats had presented the same alterations found in GC animals in M3, in major intensity, beyond mitochondrias rather modified in their form and size, cytoplasm rarefaction, vesicles increasing and nuclear alterations. It is concluded that experimental diabets causes ultra-structural of rats corneal endothelium.

Orientador : José Joaquim Titton Ranzani / Abstract: O presente estudo foi empreendido com o objetivo de estabelecer a cinética da resposta inflamatória e conhecer os mecanismos envolvidos na reparação de córneas tratadas por ceratoplastia utilizando, como método experimental, o emprego de membrana amniótica xenógena a fresco e conservada em glicerina no recobrimento de úlceras experimentais. Para o desenvolvimento da metodologia proposta utilizou-se 70 coelhos, os quais foram distribuídos em 5 grupos experimentais. Os animais foram avaliados por 21 dias, período durante o qual observou-se fenômenos relacionados à resposta inflamatória local, como dor, edema de córnea e conjuntiva, hiperemia conjuntival, além dos fenômenos relacionados à reparação da córnea, como a infiltração vascular e epitelização da úlcera experimentalmente criada. Para tanto, os olhos foram avaliados através de exame clínico oftalmológico, estudo histopatológico e reação imunohistoquímica, através da qual pesquisou-se a presença de linfócitos T na intimidade do tecido corneano. A avaliação clínica revelou que a membrana amniótica xenógena conservada em glicerina estimulou uma resposta inflamatória aguda maior que a membrana aplicada a fresco. A análise histopatológica indicou que ambas se comportaram de forma bastante semelhante a partir da 1a semana de pós-operatório, apresentando as alterações clássicas da resposta inflamatória da córnea, com o predomínio de infiltrado do tipo polimorfonuclear. Os fenômenos de reparação também evoluíram respeitando os padrões normais para ambos os tratamentos, tendo sido observado, porém, que a epitelização do defeito foi mais rápida nas córneas que receberam o enxerto de membrana a fresco. A aplicação da técnica de imunohistoquímica indicou que em nenhum momento de observação houve a migração de linfócitos T para o... (Resumo completo, clicar acesso eletrônico abaixo). / Doutor

Orientador: Cláudia Valéria Seullner Brandão / Banca: José Joaquim Titton Ranzani / Banca: Antonio Carlos Lottelli Rodrigues / Resumo: A córnea é a estrutura anterior transparente do olho e apresenta-se muito susceptível a traumas e agressões. O objetivo do presente estudo foi avaliar e comparar, clínica e histomorfometricamente, o processo de reparação corneana de úlceras induzidas em coelhos, frente à utilização do plasma rico em plaquetas (PRP) sob a forma de colírio ou tampão. Foram utilizadas 60 fêmeas da espécie leporina, constituindo-se 4 grupos experimentais de 15 animais cada, designados grupo plaquetas (GP), grupo tampão (GT), grupo controle (GC) e grupo controle amniótica (GA). Em todos os animais foi realizada a úlcera experimental, sendo este o único procedimento no GC. No GP, os coelhos foram medicados com colírio autólogo de plasma rico em plaquetas. No GC, foi instilado colírio lubrificante. No GT, foi aplicado tampão sólido rico em plaquetas, revestido por membrana amniótica, para a retenção do mesmo. No GA, foi aplicada apenas a membrana amniótica. Os grupos experimentais foram subdivididos em três subgrupos (M4, M7, M30), de acordo com os períodos finais de avaliação. Os animais foram avaliados por meio de exame clínico e histomorfométrico. Não houve diferenças entre os tratamentos utilizados quanto aos sinais relacionados à sensibilidade ocular, quemose e secreção ocular. Os grupos tratados com PRP, na forma de tampão ou colírio, apresentaram menor opacidade do que os animais tratados apenas com membrana amniótica no momento final de avaliação. Quanto à presença da úlcera corneana, os grupos tratados com PRP (GP e GT) apresentaram menor intensidade de ulceração corneana com relação aos demais grupos (GC e GA). Na avaliação histológica verificou-se maior epitelização corneana na fase inicial da lesão no tratamento à base de colírio de PRP. O uso da membrana amniótica promoveu espessamento do epitélio e estroma corneano, com sinergismo da mesma quando associada ao PRP / Abstract: The cornea is the transparent anterior part of the eye and is very susceptible to trauma and sore. The aim of this work was to evaluate and compare both, clinically and histomorphometrically the process of repair of induced corneal ulcer in rabbits using platelet-rich plasma in the form of eyedrop or clot. Sixty female leporids were divided into four groups of 15 animals, and named as platelet group (PG), clot group (CLG), control group (CG), and amniotic control group (AG). Ocular ulcer was experimentally induced in all the animals. Ulcer induction was the single procedure performed in CG. In PG, autologous platelet-rich plasma as a eyedrop was used five times a day for seven days. In CLG, a platelet-rich clot was covered by amniotic membrane to hold it in place was used. In AG, only the amniotic membrane was used. Experimental groups were then subdivided into three groups (M4, M7, M30), corresponding to the end of the evaluation period. The animals were evaluated through clinical and histomorphometric tests. There were no differences between treatments related to ocular sensitivity (blepharospasm and photophobia), chemosis and ocular secretion. The groups treated with PRP either as eyedrop or a clot, showed less opacity than the animals treated only with amniotic membrane at the moment of the final evaluation. The presence of corneal ulcers in the groups treated with PRP (PG and CLG) showed lower intensity than the other groups (CG and AG). In histological evaluation, corneal epithelization at the initial phase of the lesion was confirmed when using PRP. The use of amniotic membrane promoted corneal epithelial and stromal thickness, as well as synergism when associated to PRP / Mestre

Orientador: Newton Kara-Jose / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-13T21:12:46Z (GMT). No. of bitstreams: 1 Costa_DacioCarvalho_D.pdf: 11382661 bytes, checksum: a5c3e2c591c002085753bfe5397e34f3 (MD5) Previous issue date: 2009 / Resumo: Objetivo: Comparar a eficácia da injeção subconjuntival de 20 mg de triancinolona associada a prednisolona 1% tópica com a injeção intravenosa de 500 mg de metilprednisolona associada a prednisolona 1% tópica no tratamento da rejeição endotelial de transplante de córnea. Métodos: Estudo caso-controle realizado no Hospital das Clínicas da UNICAMP. Os pacientes submetidos a transplante penetrante de córnea que apresentaram primeiro episódio de rejeição endotelial com até 15 dias do início dos sintomas durante o período de novembro de 2005 a outubro de 2006 foram tratados com injeção subconjuntival de 20 mg de acetonido de triancinolona associado a acetato de prednisolona 1% tópico. Estes pacientes foram pareados por idade e diagnóstico com pacientes submetidos a tratamento com injeção intravenosa de 500 mg de succinato sódico de metilprednisolona associado a acetato de prednisolona 1% tópico e analisados quanto à capacidade de reversão do episódio de rejeição, pressão intraocular aos 30 dias e acuidade visual ao final de 1 ano. Resultados: 16 pacientes foram tratados com 20 mg de triancinolona subconjuntival e prednisolona 1% tópica durante o período de recrutamento e foram pareados com 16 pacientes tratados com 500 mg de metilprednisolona intravenosa e prednisolona 1% tópica. Ao final de 1 ano, o grupo tratado com triancinolona obteve melhores resultados do que o grupo tratado com metilprednisolona (p=0,025), obtendo 15 pacientes com córnea transparente enquanto o grupo tratado com metilprednisolona obteve 10 pacientes. 3 pacientes do grupo tratado com triancinolona apresentaram segundo episódio de rejeição durante o seguimento e foram retratados com sucesso enquanto no grupo da metilprednisolona, 4 pacientes apresentaram segunda rejeição, com 2 pacientes apresentando falência com o retratamento e 2 obtendo sucesso. A pressão intraocular subiu nos dois grupos (p=0,002) após 30 dias, porém não houve diferença entre os grupos (p=0,433). A acuidade visual melhorou após 1 ano em ambos os grupos (p=0,049) e o grupo tratado com triancinolona obteve melhor acuidade visual (p=0,002). Conclusão: A injeção subconjuntival de 20 mg de triancinolona combinada com prednisolona 1% tópica mostrou-se mais eficaz em reverter episódios de rejeição de transplante de córnea neste estudo caso-controle do que a aplicação intravenosa de 500 mg de metilprednisolona. Estudos adicionais necessitam ser realizados para verificar a segurança e eficácia deste tratamento em grandes populações / Abstract: Purpose: To compare the efficacy of 20 mg subconjunctival triamcinolone in association with topical prednisolone 1% to 500 mg intravenous methylprednisolone in association with topical prednisolone 1% in the treatment of cornea endothelial graft rejection. Methods: Case-control study carried out at State University of Campinas Hospital. Patients submitted to penetrating keratoplasty that presented first episode of corneal endothelial rejection within 15 days of symptoms onset between November 2005 and October 2006 were treated with 20 mg subconjunctival injection of triamcinolone acetate in association with topical prednisolone acetate 1%. These patients were matched for age and diagnosis to patients that were submitted to a single 500 mg intravenous injection of methylprednisolone sodium succinate in association with topical prednisolone acetate 1% and analyzed regarding the reversion of the rejection episode, intraocular pressure at day 30 and visual acuity at the end of 1 year. Results: 16 patients were treated with 20 mg subconjunctival triamcinolone and topical prednisolone 1% during the period of recruitment and were matched to 16 patients treated with 500 mg intravenous methylprednisolone and topical prednisolone 1%. At the end of 1 year, the group treated with triamcinolone had a better outcome than the group treated with methylprednisolone (p=0.025), having 15 patients with clear grafts as the group treated with methylprednisolone had 10 patients. 3 patients from the group treated with triamcinolone had new rejection episodes during follow-up and were retreated successfully as in the group treated with methylprednisolone 4 patients had a new rejection episode, with 2 progressing to failure and 2 to success with retreatment. Intraocular pressure rose in both groups (p=0.002) at day 30 but there were no statistically significant differences between the groups (p=0.433). Visual acuity improved after 1 year in both groups (p=0.049) and the group treated with triamcinolone had better visual acuities (p=0.002). Conclusions: 20 mg subconjunctival injection of triamcinolone acetonide associated with topical prednisolone acetate 1% showed to be more effective than 500 mg intravenous methylprednisolone associated with prednisolone acetate 1% in this case-control study. Further studies need to be accomplished to verify its safety and effectiveness in larger populations / Doutorado / Oftalmologia / Doutor em Ciências Médicas

Neste trabalho foi desenvolvido um novo instrumento para monitoramento computadorizado da curvatura da região central anterior da córnea humana durante cirurgias refrativas. Através da projeção de um disco de Plácido na córnea, imagens dos reflexos são digitalizadas e processadas. Algoritmos baseados em técnicas de visão computacional e óptica geométrica determinam a curvatura da região central (-7 mm em diâmetro), com alta precisão e desempenho. Mapas coloridos com códigos de cor em dioptrias (proporcionais ao inverso do raio de curvatura) são gerados para auxiliar o oftalmologista durante a cirurgia. / In this work we have developed a new instrument for computerized monitoring of corneal central curvature during surgery. By projecting Placido Rings on the cornea, images of the reflections are digitized and processed. Algorithms based on computational vision and optical geometry determine the central curvature (-7 mm in diameter), with high performance and precision. Color coded maps in diopters (proportional to the inverse of the radius of curvature) are generated to aid the ophthalmologist during surgery.

The Herpes simplex virus (HSV) is a virus that commonly infects the skin, and mucous membrane of the mouth, genitalia, and the eye. HSV-1 is the strain that is most commonly associated with corneal infections, and it is the most frequent cause of corneal blindness in North America [1]. Currently no cure is available, and many limitations are characterized by the currently available synthetic antiviral drugs, which suggest the need for other potential drug alternatives and delivery strategies. Anti-microbial peptides are naturally occurring peptides that are potent killers of a broad range of micro-organisms, including bacteria, fungi, and viruses [2]. AMPs are known to be a key component of the innate immune response at the human ocular surface. The human cathelicidin-derived AMP, LL-37, expressed in human corneal epithelial cells provides a wide range of protection against viral pathogens such as HSV-1 [3]. My thesis research addressed the design and recombinant production of hybrid AMP sequences containing LL-37 with the potential ability to form chemical or physical associations with a Collagen scaffold material, such as those used in current artificial cornea constructs to address the need for alternative anti-viral drugs. Three fusion proteins were tested, and compared for feasible design anti-microbial peptide expression and purification in E. coli. It was illustrated that the thioredoxin and SUMO fusion systems are good candidates for successful recombinant production of active designed peptides. The point-mutated LL-37 sequence was successfully expressed and purified using the thioredoxin fusion system. It was demonstrated that this modified LL-37 was effective against HSV-1 infection. The SUMO system was used to express the bio-functional LL-37 containing a collagen-binding sequence. Further work is required to address issues regarding recombinant AMP production, such as increasing enzymatic cleavage efficacy, and minimizing proteolytic degradation or modification.

Purpose: Solution-induced corneal staining (SICS) has been the subject of much debate in the clinical literature. While it has been suggested that this form of staining indicates toxicity of the cornea, microscopy studies have suggested that cells treated with multi-purpose solutions (MPS) known to produce SICS in vivo are undamaged. There is further debate in the literature as to whether or not sodium fluorescein (‘fluorescein’) actually enters epithelial cells or not. The aim of this work was to investigate the cellular mechanisms involved in SICS by developing an in vitro cell culture model to mimic the clinical presentation of this phenomenon. Methods: An in vitro model of SICS was developed using cultured cells that were exposed overnight to ReNu MultiPlus® (Bausch + Lomb) MPS. After addition of fluorescein, cells were imaged using an automated fluorescence microscope. Hyperfluorescent cells were identified using predetermined threshold of intensity in fluorescence microscope, and confocal microscopy was used to investigate where fluorescein was situated within the cells. The extent of cell toxicity was assessed using propidium iodide and Annexin V. In order to examine the contribution of passive and active transport mechanisms in fluorescein uptake and release, levels of hyperfluorescent staining were measured at 37°C and 4°C. In all described experiments, fluorescein staining was expressed by the proportion of hyperfluorescent cells in the total cells. Results: All cultured cells readily took up fluorescein at room temperature, however a sub-population of cells stained more intensely with fluorescein. These cells were termed ‘hyperfluorescent’ cells. Exposure to ReNu MultiPlus® resulted in a significant increase in the proportion of hyperfluorescent cells compared with control cells. In addition, the staining profiles of individual cells showed no correlation between cell death and hyperfluorescence. The data also showed that hyperfluorescence did not occur extensively in deliberately lysed cells.Addition of fluorescein to the cells at 4°C resulted in very low levels of hyperfluorescence compared to high levels at 37°C. Fluorescein was rapidly released from cells at 37°C but not from those at 4°C. Conclusion: In this work, an effective in vitro model of SICS was developed in order to provide a better understanding of the mechanisms involved in fluorescein staining. This work suggests that corneal fluorescein staining may reflect a simple cellular uptake of fluorescein. Levels of staining in the cells appear to be unrelated to cellular toxicity or cell damage. Staining appears to occur in the cytoplasm and the nucleus of the cells. Finally, fluorescein uptake and release are likely to occur through active transports mechanisms.

Ziel der Studie: Evaluation der Effektivität und Sicherheit des Kollagen-Crosslinkings der Hornhaut mit Riboflavin und UV-A (CXL) bei progressivem Keratokonus über einen Nachbeobachtungszeitraum von bis zu 10 Jahren. Design: Retrospektive klinische Längsschnittstudie Methoden: 131 Augen von 131 Patienten (männlich:weiblich = 95:36) erhielten an der Universitäts-Augenklinik Würzburg zwischen 2006 und 2016 ein Kollagen-Crosslinking (CXL) nach dem Dresdner Standardprotokoll, bestehend aus einer Abrasio, Applikation von iso-osmolaren Riboflavin/Dextran-Augentropfen für 30 min und anschließender UV-A-Bestrahlung mit 3 mW/cm2 für 30 min. Die retrospektive Nachbeobachtung betrug 1 (n=103 Augen) bis maximal 10 Jahre (n=44 Augen). Einschlusskriterien waren eine Zunahme des maximalen Hornhautkrümmungsradius (Kmax, gemessen mittels Pentacam HR) >1 dpt und eine Hornhautdicke >400 µm nach Abrasio. Für parametrische bzw. nichtparametrische Daten wurde der T-Test bzw. der Wilcoxon-Vorzeichen-Rangsummentest durchgeführt. Ergebnisse: 1 bis 3 Jahre präoperativ nahm der Median von Kmax und K2 signifikant um 1,5 dpt (p=0,001) und 1,1 dpt (p<0,001) bis zur Behandlung zu. Die apikale Hornhautdicke nahm nach 1-3 Jahren präoperativ um 12 µm ab (p=0,003). Postoperativ stieg der Median von K2 zunächst bis nach 1 Jahr um 0,1 dpt, nahm dann aber über den weiteren Nachbeobachtungszeitraum kontinuierlich ab, nach 10 Jahren lag er um 0,85 dpt (p=0,021) unter dem Ausgangswert. Die mittlere apikale Hornhautdicke nahm nach 3, 7 bzw. 10 Jahren um 11 µm (p<0,001), 9 µm (p=0,014) und 3 µm (p=0,358) ab. Der mediane Kmax zeigte Schwankungen ohne signifikante Veränderung. Der mittlere bestkorrigierte Visus (logMAR) nahm nach 5 Jahren signifikant um 0,13 und nach 10 Jahren um 0,08 ab (p=0,013 und p=0,010). Der Anteil der Non-Responder, definiert durch einen postoperativen Anstieg von Kmax>2 dpt, nahm von 16% nach 5 auf 33% nach 10 Jahren zu. Risikofaktoren waren ein junges Alter, hoher Astigmatismus, eine dünne Hornhaut und atopische Dermatitis. 4 Augen erhielten im Verlauf komplikationslos eine Revernetzung, woraufhin sich keine weitere Krankheitsprogression zeigte. Fazit: Die CXL-Behandlung kann die Progression des Keratokonus verlangsamen oder stoppen. Allerdings war ab 5 Jahren nach dem Eingriff eine Abnahme des Anteils der Responder zu beobachten. Regelmäßige Nachkontrollen sollten daher besonders auch im Langzeitverlauf durchgeführt werden, um eine erneute Progression frühzeitig erkennen und behandeln zu können. / Purpose: This study analyses long-term efficacy and safety of corneal collagen crosslinking with riboflavin and UV-A irradiation (CXL) for progressive keratoconus. Design: Retrospective longitudinal study of consecutive patients. Methods: 131 eyes of 131 patients (male:female = 95:36) were treated at the university hospital Wuerzburg between 2006 and 2016 with standard CXL, comprising abrasion, application of iso-osmolar riboflavin/dextran eye drops for 30 min, and application of UV-A irradiation at 3 mW/cm2 for 30 min. Retrospective follow-up was 1 (n=103 eyes) to maximum 10 years (n=44 eyes). Only one eye per patient was included. Inclusion criteria were increase of maximum surface radius of curvature (Kmax measured with Pentacam HR) >1 D and corneal thickness >400 µm after abrasion. Paired t test or Wilcoxon matched-pairs signed rank test were conducted for parametric or nonparametric data, respectively. Results: 1 to 3 years preoperatively, median of Kmax and K2 significantly increased by 1.5 D (p=0.001) and 1.1 D (p<0.001). Apical corneal thickness diminished by 12 µm at 1-3 years preop (p=0.003). After CXL, median K2 increased by 0.1 D after 1 year, but then decreased over the remaining postoperative period by 0.85 D (p=0.021) after 10 years. Mean apical corneal thickness decreased by 11 µm (p<0.001), 9 µm (p=0.014) and 3 µm (p=0.358) after 3, 7 and 10 years, respectively. Median Kmax showed high variation without significant change. Mean best corrected visual acuity (logMAR) significantly decreased by 0.13 after 5 and 0,08 after 10 years (p=0.013 and p=0.010). CXL-non-responders, defined by postoperative increase of Kmax>2 D, increased from 16% after 5 to 33% after 10 years. Risk factors were young age, high astigmatism, thin cornea, and atopic dermatitis. 4 eyes were re-treated after first CXL without any complications and keratoconus stabilized thereafter. Conclusion: CXL can slow down or stop the progression of keratoconus. However, the declining responder rate beyond 5 years after treatment indicates that patients who have risk factors for being a non-responder might require re-treatment. So patients should be examined at regular intervals especially after 5 years post CXL, to recognize and re-treat a progression early.

No description available.