Ceratite ulcerativa é uma das enfermidades oculares mais comuns em cães e requer tratamento clínico-cirúrgico urgente. Neste contexto, o tratamento cirúrgico com implante de membrana biológica é opção benéfica. Estudou-se o implante de membrana amniótica (MA) e membrana alantoamniótica (MAAM) alógenas preservadas em glicerina a 98% em vinte córneas de cães submetidas previamente à ceratectomia lamelar superficial. Dividiram-se os cães em dois grupos para o estudo aos 2, 7, 15, 30 e 60 dias de pós-operatório. Avaliaram-se, segundo parâmetros clínico-oftalmológicos e histopatológicos. Clinicamente detectou-se fotofobia e blefarospasmo, tipos e graus de secreção, edema e neovascularização corneana e transparência da córnea no local do implante. Nos períodos pré-determinados as córneas foram submetidas à avaliação histológica. Foram constatados, com base no exame ocular, graus leves a moderado de fotofobia e blefarospasmo; predominou o tipo de secreção mucoso com grau moderado e o edema corneano permaneceu leve no grupo que recebeu MA, e moderada a leve no grupo que recebeu MAAM. A neovascularização intensificou-se no 15º dia de pós-operatório em ambos os grupos. Com base nos achados histopatológicos os grupos evoluíram de forma semelhante; constatou-se o desenvolvimento do processo de cicatrização dentro dos parâmetros normais para a córnea. Concluiu-se que a utilização da MA comparada com a MAAM de cães preservadas em glicerina a 98% em ceratoplastias não diferem quanto sua evolução segundo os parâmetros adotados para análise. Ambas as membranas são igualmente efetivas como membrana biológica alógena na reparação de defeito corneano. / Ulcerative ceratitis is one of the most frequent ocular diseases in dogs and it requires prompt surgical and clinical therapy. In this context, surgical treatment using biological membrane implants is a benefic option. In this study alogenous 98% glycerin-preserved amniotic (MA) and alantoamniotic (MAAM) membranes were implanted on twenty corneas from dogs previously submitted to superficial lamellar keratectomy. Clinical, ophthalmologic and histological parameters were investigated. The animals were divided in two groups and pos-operative corneal histological evaluation was taken on days 2, 7, 15, 30 and 60. Photophobia, blefarospasm, different types and severity of ocular secretion, corneal edema and neovascularization and corneal transparency at the implant site. Ocular examination revealed mild to severe photophobia and blefarospasm, moderate mucous secretion was the most frequent. Corneal edema was mild in the MA group and mild to moderate in the MAAM group. From the 15th pos-operative day neovascularization was more pronounced for both groups. Based on the histological findings the groups showed similar evolution and the healing process was found to be within normal parameters for the corneal tissue. We concluded that in dogs 98% glycerin-preserved MA and MAAM applied to keratoplasty do not differ among the parameters evaluated. Both membranes are equally effective as allogenous biological membrane for the repair of corneal defects.

Teng, Yufei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 175-193). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

Orientador: Alexandre Lima de Andrade / Banca: Silmara Sanae Sakamoto de Lima / Banca: Flávia Rezende Eugênio / Resumo: As neoplasias oculares representam uma crescente preocupação na oftalmologia veterinária. O carcinoma de células escamosas (CCE) corneal é raro em cães, pouco estudado e as investigações sobre os mecanismos da carcinogênese são escassos. O presente trabalho teve por objetivo avaliar a imunoexpressão das proteínas p53, p63 e PUMA e suas possíveis contribuições quanto ao prognóstico e terapêutica no CCE corneal espontâneo de cães. Foram identificados seis casos, cinco diagnosticados como CCE e um como ceratite actínica. Na imunoistoquímica avaliou-se o número de células marcadas por campo no microscópio adotando-se dois critérios de classificação, quanto à intensidade e quanto à frequência de marcação. Também foi avaliada a graduação histológica dos tumores quanto ao grau de malignidade nos casos de carcinoma de células escamosas de córnea, utilizando o índice mitótico como principal referência. Todas as amostras apresentaram imunomarcação para as proteínas estudadas, porém com intensidade e frequência variadas. Não foi observada relação entre maior índice mitótico e, portanto, maior malignidade, com uma maior expressão de qualquer uma das proteínas analisadas. Conclui-se que a imunoexpressão das proteínas p53, p63 e PUMA estão presentes nos CCE corneal de cães podendo contribuir para sua carcinogênese, mas não fornece indicadores de prognóstico nesta neoplasia / Abstract: Ocular tumors play an increasing concern in veterinary ophthalmology. Corneal squamous cell carcinoma (SCC) is unfrequent in dogs, and by this way it has little studies, and the investigations of carcinogenesis mechanisms are rare. The aim of this work was to identify the p53, p63 and PUMA proteins expression in the spontaneous dog corneal SCC. For this work, were used five cases of corneal SCC and one case of actinic keratitis and their possible contributions to prognosis and therapy. The immunohistochemical analysis could evaluated the number of stained cells by field in optic microscopy using two classifications methods: intensity and immunofrequency. Also, we could evaluated histological grade of tumor related to malignancy in corneal SCC cells by using the mitotic index as a pattern. All samples showed immunolabelling to those proteins studied, although with diversity in intensity and frequency. The authors couldn't observe relationship between the biggest mitotic index, and, by this way, most malignancy, with the expressions of all analysed proteins. These results could support the conclusions that p53, p63 and PUMA proteins immunoexpression are present in canine corneal SCC and could give help to their carcinogenesis, but they don't give a prognostic indicator of these tumors / Mestre

Objetivo: Avaliar a função visual de pacientes submetidos a transplante lamelar anterior profundo (DALK) utilizando a dissecção com tunelizador manual e fio. Métodos: Foram incluídos 33 pacientes com ceratocone que apresentavam BCVA <= 0,60 LogMar, miopia e astigmatismo entre 8,00 e 10,00D, K central médio > 53,00D, ausência de cicatrizes, espessura corneana mínima entre 300 e 400 um. Foi feita avaliação oftalmológica completa no pré e no pós-operatório de 6 a 8 meses. Estas avaliações foram complementadas com exame topográfico da córnea, microscopia especular para avaliação da densidade das células endoteliais corneanas, aberrometria corneana e exame de tomografia de coerência óptica do segmento anterior. As variáveis BCVA, UCBA e os valores totais das aberrações corneanas de alta ordem foram correlacionadas com a espessura do leito estromal residual. Resultados: Os pacientes submetidos à DALK apresentaram BCVA de 0,68 ± 0,27 LogMar o que representa BCVA superior a 20/40 em 60% da amostra analisada. Não foram observadas micro ou macroperfurações. Houve diminuição na contagem endotelial de 2702,87 ± 548,87 células por mm2 para 2282,10 ± 525,66 células por mm2 . A dissecção do estroma profundo com o fio facilitou a remoção de tecido estromal posterior, fato corroborado com o achado de que o leito residual estromal aferido foi de 49,18 ± 18,36 ?m na região central e foi inferior a 80 ?m em grande parte dos pacientes estudados. No que se refere à regularidade da dissecção, observou-se tendência a valores mais elevados de espessura residual na periferia (60,09 ± 17,70 ?m). Não houve correlação da BCVA, UCVA e do total de aberrações de alta ordem da córnea com a espessura do leito estromal residual. Conclusão: A apreciação dos resultados desse estudo mostrou que com a técnica utilizada para realização de DALK em portadores de ceratocone obteve-se resultados topográficos e funcionais semelhantes a outras técnicas consagradas pela literatura. A facilidade na dissecção do estroma profundo, a regularidade da dissecção e a presença de baixíssimo índice de conversão para transplantes penetrantes são encorajadores / Objective: Evaluate the visual function of patients undergoing deep anterior lamellar keratoplasty (DALK) using a manual spatula and a wire dissection. Methods: Thirty three keratoconus patients were included, meeting the following inclusion criteria: BCVA logMAR <=0,60, myopia and astigmatism between 8.00 and 10,00D, K central average > 53.00D, no corneal scars and minimal corneal thickness between 300 and 400 um. Complete ocular evaluation was performed preoperatively and postoperatively in 6-8 months. These assessments were supplemented by topographical survey of the cornea, specular microscopy to evaluate the density of corneal endothelial cells, corneal wavefront analysis and examination of optical coherence tomography of the anterior segment (Visante). The BCVA variables, UCVA and the total amounts of corneal higher-order aberrations were correlated with the the residual stromal bed thickness. Results: Patients that undergone to DALK with the described technique presented a BCVA of 0.68 ± 0.27 logMAR which represents a BCVA of more than 20/40 at 60% of the analyzed sample. There were no micro or macroperforations. We observed a small decrease in the endothelial cell count from 2702.87 ± 548.87 cells per mm2 to 2282.10 ± 525.66 cells per mm2. The dissection of the deep stroma with a wire facilitated the posterior stromal tissue removal, thus the measured stromal bed thickness was 49.18 ± 18.36 ?m in the central region and less than 80 ?m in the majority of the studied patients. As regards the dissection regularity, we showed a tendency to higher values of residual thickness at the periphery (60.09 ± 17.70 ?m). There was no correlation of the BCVA, UCVA and total corneal higher-order aberrations with the residual stromal bed thickness. Conclusion: The assessment of the study data showed that the described technique achieved a topographical and functional result similar to other techniques consecrated by literature. The shallow learning curve, the ease to perform the dissection of the deep stroma, the postoperative stromal regularity and the presence of very low conversion rate for penetrating keratoplasty are encouraging

A radiação ultravioleta pode tanto ser um benefício, como um malefício para o olho humano. Os benefícios são quando é utilizada em procedimentos oftalmológicos para a correção da visão, como nas cirurgias foto-refrativas - UVC - 193 nm; ou para, entre outros tratamentos, impedir a progressão de patologias, como é o caso do crosslinking do colágeno corneano, para ceratocones em estágios inicias que utiliza UVA - 370 nm. Os malefícios são os já amplamente conhecidos pela comunidade científica e populacional, sobre a incidência excessiva de radiação UV nos olhos, causando danos severos ao olho humano. Entretanto, a córnea tem uma proteção natural contra os raios UVA e UVB. Neste trabalho, estudou-se os dois procedimentos oftalmológicos citados a fim de investigar possíveis danos ao olho humano, como a perda da proteção natural da córnea pós cirurgia foto-refrativa, que retira lamelas da córnea; e a quantidade de radiação que adentra o olho humano, durante o crosslinking do colágeno corneano, que utiliza Riboflavina como sintetizador e bloqueador da radiação UVA. Um sistema portátil foi desenvolvido para avaliação da proteção UV e seus danos para o primeiro caso. O protótipo consiste de um sistema de duplo feixe e analisa a transmitância do tecido corneano na faixa de 300-400 nm, e apresenta um fator de correlação r2>0,98. As medidas com remoção de tecido indicaram a importância das camadas da córnea, e a remoção do estroma apresentou uma perda significativa da proteção natural UV, com aumento de 8,2-10,1 pontos percentuais. Já para o crosslinking, que utiliza a combinação riboflavina e UVA, com irradiância de 3 mw/\'CM POT.2\' por 30 minutos foi feito o monitoramento da transmitância UVA durante o tratamento. Foi realizado o protocolo do procedimento atual, ou seja, uma gota de Riboflavina 0,1%, 400mOsm, foi instilada na córnea desepitelizada, a cada 5 minutos (total de 12 gotas). A irradiação UV (365 ± 5 nm, 3 mW/\'CM POT.2\') foi realizada após 30 min de instalação por uma adicional de mais 30 min. A transmitância média da córnea desepitelizada sem Riboflavina foi de 61,6%; após a 1ª instilação de Riboflavina a transmitância foi de 44,9%; após a 6ª gota 22,4%; após a 7ª gota (início da irradiação), 19,5%; após a 8ª gota, 17,3%; após a 9ª, 15,8%; após a 10ª; 14,5%; após a 11ª; 13,5%; e após a 12ª instilação, 12,6%. A transmitância média em termos de energia durante os 30 min de irradiação apresentou uma variação de 0,590 até 0,380 mW/\'CM POT.2\', valores além do limite atualmente aceito para endotélio de córneas de coelhos, que apresenta um nível de segurança citotóxico de 0,36 mW/\'CM POT.2\'. / Ultraviolet radiation can either be a benefit as an harm to the human eye. The benefits are when used in ophthalmic procedures for vision correction, as in the photorefractive surgery - UVC - 193 nm; or to, among other treatments, preventing the progression of diseases, such as the corneal collagen crosslinking, for keratoconus in the early stages - that uses UVA - 370 nm. The harm effects are already widely known by the scientific community and general population, about excessive incidence of UV radiation in the eye, that can cause severe damage to the human eye. However, the cornea has a natural UVA and UVB protection. In this work, we studied the two ophthalmic procedures cited in order to investigate possible damage to the human eye, as the loss of cornea UV natural protection after photorefractive surgery, which removes corneal lamella; and the amount of radiation that penetrates the human eye during the corneal collagen crosslinking, that uses Riboflavin as a synthesizer and UVA radiation blocking. A portable system was developed to evaluate the UV protection and the UV damage for the first case. The prototype consists of a double beam system that analyzes the corneal tissue transmittance in the 300-400 nm range, and presents a correlation factor r2>0.98. Measurements with tissue removal showed the importance of each corneal layer, specially the stroma removal that shows a significant loss of natural UV protection, with an increase of 8.2 to 10.1 percentage points. As for the crosslinking, using riboflavin and UVA irradiance combination, with 3 mw/\'CM POT.2\' for 30 minutes, was performed a monitoring of UVA transmittance during treatment. Current procedure protocol was performed, i.e., one drop of riboflavin 0.1%, 400mOsm, was applied on the naked cornea, every 5 minutes (total of 12 drops). The UV irradiation (365 ± 5 nm, 3 mW/\'CM POT.2\') was performed after 30 min of instillation for an additional 30 min. The average transmittance of the desepithelized cornea without Riboflavin is 61.6%; after the 1st drop of Riboflavin, transmittance is 44.9%; after 6th drop 22.4%; after 7th drop (irradiation starts), 19.5%; after 8th drop; 17.3%; after 9th drop, 15.8%; after 10h drop, 14.5%; after 11th drop, 13.6%; after 12th drop, 12.6%. The average transmittance in terms of energy during the 30 min irradiation procedure fluctuated from 0.590 to 0.380 mW/\'CM POT.2\', beyond the currently accepted rabbit corneal endothelium safety limit for cytotoxic level of 0.360 mW/\'CM POT.2\'.

OBEJTIVOS: Analisar a segurança e eficácia da cirurgia de crosslinking (CXL) de córnea em pacientes com ceratocone em estágios avançados após um seguimento de 4 anos. MÉTODOS: Trata-se de um estudo retrospectivo de pacientes com ceratocone avançado em progressão (Estágio 3 e 4 da classificação de Amsler-Krumeich) que foram submetidos a cirurgia de CXL seguindo o protocolo padrão. Os parâmetros examinados foram acuidade visual com (AVCC) e sem (AVSC) correção, valores ceratométricos (média, plana, curva e apical), paquimetria, e contagem de células endoteliais no préoperatório e após 12, 24 e 48 meses do procedimento. RESULTADOS: Este estudo abrange quarenta olhos de 40 pacientes que foram submetidos a cirurgia de CXL. A média de idade foi 22,5 anos (Intervalo:15 a 37 anos). Tanto a AVSC quanto a AVCC permaneceram estáveis durante o período de seguimento, sem mudanças estatisticamente significativas. Apesar de todos os valores ceratométricos sofrerem uma leve diminuição, apenas a ceratometria apical atingiu uma mudança com significado estatístico (P=0,037) após 4 anos de seguimento. Uma redução significativa da espessura corneana foi também observada (paquimetria ultrassônica era de 388 ± 49 e passou para 379 ± 48 ?m, P < 0,0001; paquimetria através de tomografia de imagem em fenda era de 362 ± 48 e foi para 353 ± 51 um, P < 0,0001); embora essa diferença não seja clinicamente significativa. A contagem de células endoteliais não sofreu alterações significativas durante o seguimento. A taxa de falha do tratamento foi de 5% (dois pacientes) durante o seguimento. CONCLUSA?O: A cirurgia de CXL corneano em pacientes com ceratocone avançado se mostrou segura e capaz de manter os parâmetros visuais e topográficos pelo menos durante 4 anos / PURPOSE: To analyze the safety and efficacy of standard corneal collagen crosslinking (CXL) in advanced cases of progressive keratoconus (KC) after four years of follow-up. METHODS: A retrospective case series of patients with advanced progressive KC (stage 3 and 4 of Amsler-Krumeich classification) underwent standard CXL treatment. The parameters examined were changes in uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), keratometry values (mean K, flattest K, steepest K, and apical K), pachymetry, and endothelial cell count at the baseline and at 12-, 24- and 48-months postoperatively. RESULTS: Forty eyes of 40 patients were enrolled into the study. The mean patient age was 22.5 years (range: 15 to 37 years). Both mean UCVA and CDVA remained stable during the time points; no statistically significant change was noted. Although a slightly reduction was observed in all keratometric readings, a statistically significant reduction was only reached in the apical K (p=0.037) at four years after CXL. A significant reduction in the pachymetry was also found (from 388±49 to 379±48 um, P < 0,0001 and from 362±48 to 353±51 um, P < 0,0001, ultrasonic and slit-scanning readings, respectively) ; however this change is not likely clinically meaningful. Endothelial cell count was not significantly modified at the end of the study. Treatment failure or progression was noted in two patients (5%) over the followup period. CONCLUSION: Standard CXL treatment seems to be safe and able to stabilize both visual acuity and topographic parameters at four-year follow-up in advanced keratoconic eyes

Purpose: Corneal transparency depends upon the precise organization of corneal stromal extracellular matrix and corneal endothelial function. Stromal structure and extracellular matrix organization is responsible for proper refraction of light into the eye. The corneal endothelium is responsible for pumping excess fluid out of the cornea, effectively maintaining corneal hydration and thickness. Corneal transplantation is the current form of treatment for corneal endothelial and stromal dystrophies. The mechanisms controlling stromal collagen fibril packing and organization into orthogonal layers as well as maturation of the endothelium into a fully functioning cellular layer are unknown. Collagens XII and XIV, fibril associated collagens with interrupted triple helices (FACIT), have been implicated in matrix-matrix interactions regulating structure, cell behavior, and cell-matrix interactions. The overall aim is to determine the role of collagens XII and XIV in fibril assembly, fibril packing, lamellar assembly, stromal organization, corneal thickness, and endothelial maturation. The general hypothesis is that collagens XII and XIV regulate cornea stromal matrix development and structure, endothelial development, and corneal function. This dissertation assesses three specific hypotheses: 1) Collagen XIV regulates lateral fibril growth and fibril packing through fibrillar surface interactions; 2) Collagen XII regulates fibril packing, lamellar assembly, stromal organization, corneal thickness, and therefore, corneal function; and 3) FACIT collagens in the specialized posterior stroma regulate the acquisition of function in the corneal endothelium. Materials and Methods: The temporal and spatial expression patterns of collagens XII and XIV were determined in the murine cornea using quantitative PCR, semi-quantitative immuno-blots and immuno-localization approaches. To determine the regulatory roles of collagens XII and XIV in stromal and endothelial development, mouse models null for collagens XII or XIV were. This was coupled with ultrastructural and morphometric analyses of fibril assembly, fibril packing, lamellar organization, and endothelial maturation. The roles of collagens XII and XIV in corneal structure were determined using measurements of corneal thickness at postnatal day (P) 30 and P60. Results: Collagen XIV had a dynamic expression pattern in wild type (WT) corneal development. Corneas at P4 expressed the highest amount of collagen XIV with a sharp reduction by P10. Collagen XIV localized in the full thickness of the stroma at P4 and P14. At P30 and P90 there was less immuno-reactivity for collagen XIV in the WT stroma. The collagen XIV null stromas contained larger diameter fibrils when compared to P30 WT stromas. The null stromas also exhibited irregular spacing of fibrils. In the absence of collagen XIV there was an abnormal increase in corneal thickness. Unlike collagen XIV, collagen XII localized homogenously throughout the WT corneal stroma from P4 to P90. Collagen XII content was relatively constant in the cornea from P4 to P90. The collagen XII P30 null stromas contained areas of increased fibril density and disruption of lamellar organization. Corneal thickness increased in the absence of collagen XII at P60. Corneas deficient in Col12a1-/- and/or Col14a1-/- exhibited a delay in maturation. The null corneal endothelia retained vacuoles seen only in the immature WT P4 cornea. The P30 Col12a1-/- and Col14a1-/- endothelia had patchy localization of ZO-1 similar to that of an immature endothelium. There was an abnormal increase in thickness at P30 in the absence of collagens XII and XIV suggesting an increase in stromal hydration. Conclusions: Collagen XIV regulates fibril assembly, and regular fibril packing in early stromal development. Collagen XII regulates fibril packing, lamellar assembly, stromal organization, and influences the keratocyte network. Both collagens XII and XIV regulate endothelial maturation and acquisition of function through interactions between the stroma and underlying endothelium. Understanding the mechanisms behind stromal organization and endothelial maturation will improve treatment of stromal and endothelial dystrophies, as well as other diseases that involve extracellular matrix-cell interactions mediated by FACIT collagens.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 138-153).

Recurrent corneal erosions are a common complication of superficial corneal wounds. They most commonly arise following a trauma, in association with various corneal dystrophies, or are idiopathic. The main aim of this thesis was to investigate two hereditary corneal diseases with recurrent erosions in order to find out if they had been described before, and more specifically to describe the clinical picture and the morphological changes, differentiate them from other known autosomal dominant corneal dystrophies with a clinical resemblance, and to exclude genetic linkage to known corneal dystrophies with autosomal-dominant inheritance and a clinical resemblance. The thesis is based on two families of subjects belonging to different phenotypes. The subjects from Småland (Dystrophia Smolandiensis) belonged to a six-generation family, which included 171 individuals of whom 44 were affected individuals, and the family from Hälsingland (Dystrophia Helsinglandica) included sevengenerations of 342 individuals, of whom 84 were affected. The individuals in both families were investigated by collection of medical history through medical records and questionnaires assessing different aspects of the diseases, pedigree analysis, and from clinical examination. Haplotype analysis was used to exclude genetic linkage of both diseases to known autosomal-dominant corneal dystrophies with a clinical resemblance. The morphological changes in Dystrophia Smolandiensis were investigated by examining affected individuals with in-vivo confocal microscopy and/or slit-lamp biomicroscopy, and examining corneal tissue samples using histopathology and immunohistochemistry. In Dystrophia Helsinglandica, the morphological changes were described using in-vivo confocal microscopy and/or slit-lamp biomicroscopy, but also using videokeratography and corneal sensitivity measurement. The main results were the findings of two new corneal disorders with autosomal dominant inheritance, characterized by recurrent corneal erosions. In Dystrophia Smolandiensis the symptoms often started within the first year of life. The number of recurrences per year was highest from the onset and for about 30-40 years, and the duration of recurrence could stretch up to 21 days. The frequency of recurrences was variable in the disease from continuous symptoms to once a year and tended to decrease later in life. The risk of having recurrences did not disappear completely with age. Typical precipitating factors of recurrence were draught and a common cold. About two thirds of the affected individuals responded well to oral vitamin B treatment, but no other therapy has so far been successful. In Dystrophia Smolandiensis development of corneal opacifications or secondary scarring of varying type and degree was seen in about half of the subjects. Opacifications were first noted at the age of about 7 years, but usually first seen at the age of 20-40 years. Corneal grafting was performed in nine individuals, and recurrences were seen in all grafts. The corneal buttons showed epithelial hyperplasia, partial or total loss of Bowman’s layer, and subepithelial fibrosis in the light microscope. The deeper stroma, Descement’s membrane, and endothelium were normal. Confocal microscopy confirmed loss of Bowman’s layer and revealed that the corneal nerves either were normal in their sub-basal plexa or showed signs of regeneration. None of the morphological findings were specific. We believe that the opacifications are reactive corneal changes to repeated erosive events. The onset in Dystrophia Helsinglandica was usually at the age of 4-7 years and late-developing subepithelial fibrosis not significantly affecting visual acuity was seen in all affected individuals over the age of 37 years. The number of recurrences per year was highest from the onset and for about 20-30 years, and the duration of recurrence was usually up to about a week. The frequency of recurrences tended to decrease in the disease with increasing age, but did not cease completely. The precipitating factor of recurrence was typically a minor trauma. No therapy has so far been successful in the family. The corneal changes of affected individuals were classified into different stages from a nearly normal cornea to progressive fairly discrete subepithelial fibrosis of the central cornea. Discrete localized Subepithelial fibrosis in the periphery or mid-periphery (stage I) was the sole finding in 12% of the individuals. A more widespread subepithelial fibrosis, mainly in the mid-periphery, was found in 31% of the individuals (stage II). In stage III, the subepithelial fibrosis engaged the central cornea but did not affect the vision to a significant degree. In late phases of stage III small jellylike corneal irregularities could be seen. We believe that the opacifications are reactive changes to repeated erosive events. In conclusion this thesis describes two new corneal disorders – Dystrophia Smolandiensis and Dystrophia Helsinglandica.

Cornea is the transparent outermost layer of the eye. It is a thin (500 &micro / m) multilayer tissue which performes around 75% of the total refraction in the eye. It also protects the inner layers against any type of damage. Since it is avascular, the three cellular layers of cornea always need transport of nutrients and other materials in and out of the tissue via diffusion. Any change in shape, transparency or thickness of cornea, or physical damages and infections, may cause serious defects. The conventional methods are satisfactory in the treatment of mild injuries but severe cases require the substitution of the tissue with an equivalent. Keratoprosthesis and donor corneas that are used as replacements do not completely meet requirements. Tissue engineering can be an alternative method for preparing a biocompatible and stable cornea equivalent. The ability to choose from a variety of materials and the ability to incorporate bioactive agents allow the researchers to tailor make the construct. The structure needs to be seeded with the patient&rsquo / s own cells and cultured in vitro to yield an optimal corneal replacement. In this study a novel, split thickness cornea replacement is proposed to substitute the two upper cellular layers (epithelium and stroma) of the native cornea. The design includes a chondroitin sulfate impregnated collagen type I (isolated from rat tail) foam (CSXLF) produced by lyophilization carrying electrospun fibers of the same polymer collected directly on top of the foam, forming the bilayer structure (Fo-Fi). The fiber layer was intended to separate the epithelium and the stroma of the reconstructed cornea yet to allow material transfer in between. The foam layer (bottom) was crosslinked by N-ethyl-N-[3-dimethylaminopropyl] carbodiimide (EDC), and N-hydroxy succinimide and after fiber deposition the bilayer was further stabilized with physical crosslinking (DHT method). The physical characterization of the foam showed that their pore sizes (10-200 &micro / m) and porosities (around 70%) were well within the desired range for typical tissue engineering applications. The cell free wet thicknesses of both single and bilayer constructs were close to that of the native stroma and light transmittance through these scaffolds was quite high (around 82% in the 500-700 nm range). The scaffolds were also tested for their stability and shown to be suitable for in vitro testing. In vitro studies were performed using retinal pigment epithelial cells (RPE, D407 cell line) and isolated human corneal keratocytes (HK) to reconstruct the epithelium and the stroma, respectively. Three types of constructs were prepared / only HK seeded Fo-Fi constructs, RPE-HK seeded CSXLFs, and RPE-HK seeded Fo-Fi constructs. All were shown to support cell attachment and promoted cell proliferation as was shown by the cells that covered the inner and outer spaces of the scaffolds. The fiber layer prevented the mixing of the two cell types, without hindering material exchange between them. Moreover, when co-cultured for 14 days, the keratocytes started to deposit collagen type I, a specific marker of these cells. In contrast, ECM deposition could not be observed in the single type cell seeded samples. The co-cultured bilayer construct was tested for suturability at the end of 31 days of in vitro incubation and it was shown that it could be successfully sutured without any major tears. Under the light of these results it was concluded that both the single layer and the bilayer constructs show promise for use as split thickness cornea replacements.