Academic literature on the topic 'Ocular transplant'
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Journal articles on the topic "Ocular transplant"
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Cardoso, Mayk Penze, Marcos Antonio Ferreira Junior, Oleci Pereira Frota, Elen Ferraz Teston, and Maria Eduarda Gonçalves Zulin. "Epidemiological analysis of corneal donors and patients queuing for keratoplasty." Conjecturas 22, no. 16 (2022): 310–25. http://dx.doi.org/10.53660/conj-2027-mp23b.
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Purpose: To characterize corneal donors and patients on the waiting list for keratoplasty clinically and epidemiologically. Methods: Epidemiological, cross-sectional study with a sample of 1,303 donors and 938 patients on the waiting list were analyzed. Performed in MS State Transplant Center (STC) and the Human Ocular Tissue Bank, from January to June 2019. For the qualitative variables, descriptive analysis was performed. In the quantitative variables, trend and data dispersion measures were analyzed. Results: Of the 2,606 corneas, 31.73% were transplanted, 21.64% of donors were reagents for infectious diseases that contraindicated transplantation, with a higher percentage of reagents in donors aged over 50 years (p <0.001). Keratoconus stood out as the main ocular diagnosis in the frequency distribution. The average age found for patients in the waiting line was 49.05 years. Regarding the average waiting time to perform the transplant, it was 108.46 days for elective transplants and 11.0 days for emergency transplants. Conclusion: More than 40% of the tissues taken from donors were discarded, with emphasis on epithelial defects and reagent serologies. Keratoconus was the main indication of patients queuing for keratoplasty.
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Chen, Yun-Wen, Hun-Ju Yu, Yi-Chieh Poon, and Hsi-Kung Kuo. "Ocular post-transplant lymphoproliferative disorder." Taiwan Journal of Ophthalmology 5, no. 3 (2015): 140–42. http://dx.doi.org/10.1016/j.tjo.2014.06.001.
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Belal, Amer A., Andrew Slater, Jinghua Chen, Alfonso Santos, and Muhannad Leghrouz. "Ocular Toxoplasmosis After Kidney Transplant." Journal of the American Society of Nephrology 34, no. 11S (2023): 614. http://dx.doi.org/10.1681/asn.20233411s1614a.
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Vorobyeva, I. V., E. V. Bulava, L. K. Moshetova, and A. V. Pinchuk. "Ocular changes after simultaneous kidney-pancreas transplant." Russian Journal of Clinical Ophthalmology 22, no. 2 (2022): 132–36. http://dx.doi.org/10.32364/2311-7729-2022-22-2-132-136.
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Type 1 diabetes (T1D) is one of the most common chronic diseases in young individuals. Diabetic nephropathy, being one of the most dangerous complications of T1D, progresses to end-stage renal disease within 10–15 years in 80%. The simultaneous kidney-pancreas transplant prevents insulin therapy and dialysis, thereby avoiding further progression of complications of diabetes. Normalization of carbohydrate metabolism and resolving of uremia after simultaneous kidney-pancreas transplant are beneficial for ocular structures. This article reviews studies on the pattern of changes in ocular structures in the post-transplant period. The procedure improves peripheral microcirculation of the bulbar conjunctiva and corneal innervation. Most studies demonstrate stabilization and improvement of the course of diabetic retinopathy as illustrated by the reduction in active vascular proliferation, need for retinal laser photocoagulation and vitrectomy. Meanwhile, some studies failed to reveal any differences in the morphological functional status of the retina in the pre- and postoperative periods. An increase in cataract rate among simultaneous kidney-pancreas transplant recipients receiving immunosuppressant therapy remains a challenge. Keywords: type 1 diabetes, kidney transplant, pancreas transplant, simultaneous kidney-pancreas transplant, diabetic retinopathy, diabetic macular edema. For citation: Vorobyeva I.V., Bulava E.V., Moshetova L.K., Pinchuk A.V. Ocular changes after simultaneous kidney-pancreas transplant. Russian Journal of Clinical Ophthalmology. 2022;22(2):132–136 (in Russ.). DOI: 10.32364/2311-7729-2022-22-2-132-136.
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Jain, Apoorva, Snigdha Sen, Dharmendra Singh Bhadauria, Anu Jain, and Merensoba T. Imchen. "The Spectrum of Ocular Manifestations among Renal Transplant Recipients." Indian Journal of Transplantation 18, no. 1 (2024): 63–67. http://dx.doi.org/10.4103/ijot.ijot_79_23.
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Purpose: The study aims to report various ocular manifestations among renal transplant recipients. Methods: The cross-sectional study was conducted on renal transplant patients, with at least 4 months of posttransplant duration, attending a nephrology clinic. A comprehensive ophthalmic evaluation was performed to record various ocular manifestations. The statistical association between ocular findings and pretransplant as well as posttransplant duration was assessed. Results: One hundred and twenty-three eyes of 62 patients, with a mean age of 37.6 ± 8.2 years and functional graft, were included in the study. Diabetic nephropathy was found to be the most common underlying cause of end-stage renal disease (ESRD) and renal transplant. Hypertensive retinopathy (37.4%) was found to be the most frequent ophthalmic manifestation, followed by diabetic retinopathy (24.39%), dry eye (22.76%), cataract (18.69%), and change in refractive error (17.89%). The occurrence of hypertensive retinopathy and refractive power change was found to be significantly associated with pretransplant dialysis duration. In contrast, concerning the posttransplant period, the frequency of all the major ocular manifestations, except the dry eye, was observed to be statistically significant. Conclusion: Patients with ESRD and renal transplant should be advised to undergo regular comprehensive eye examinations. Many ocular manifestations are preventable and/or treatable, thus interdisciplinary partnership between nephrologists and ophthalmologists is warranted to improve vision and quality of life in transplant recipients.
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Potenza, Michele, Antonio Moramarco, Annalisa Astolfi, Carmen Ciavarella, Luigi Fontana, and Piera Versura. "Ocular Surface Microbiota and Corneal Transplant Outcome: Is There a Link?" Biomedicines 13, no. 4 (2025): 972. https://doi.org/10.3390/biomedicines13040972.
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Recent research has highlighted the critical role of microbiota in organ transplant outcomes, particularly in the gut. However, the impact of ocular surface microbiota (OSM) on corneal transplantation remains largely unexplored. This piece examines the potential connection between OSM imbalances and corneal graftoutcomes, suggesting that microbial shifts could influence immune responses and transplant success. The OSM, though characterized by low microbial density, plays a critical role in local immune modulation and ocular surface homeostasis. Dysbiosis in this microbiota may compromise the immune privilege of the cornea, potentially increasing the risk of graft rejection. Looking at gut microbiota studies, where dysbiosis has been linked to graft failure, it is reasonable to hypothesize that similar mechanisms might be at play on the ocular surface. Disruptions in cornea’s immune tolerance pathways, such as anterior chamber-associated immune deviation (ACAID), may lead to pro-inflammatory responses that threaten graft survival. In addition, ocular surface diseases such as dry eye disease, microbial keratitis, and allergic conjunctivitis, already associated with OSM dysbiosis, may further exacerbate post-transplant complications. Despite the lack of direct studies linking OSM to corneal transplant outcomes, this opinion piece highlights the necessity for future research. Standardizing microbiota analysis methodologies and exploring therapeutic interventions, such as ocular probiotics, could open new roads for improving corneal transplant success and patient prognosis.
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Choudhry, Hassaam S., Aretha Zhu, Hannaan S. Choudhry, Nikolaos Pyrsopoulos, and Mohammad H. Dastjerdi. "Vitamin A Deficiency Screening in Patients With Chronic Alcohol-Associated Liver Disease: Implications for Liver Transplant Candidates." ACG Case Reports Journal 10, no. 7 (2023): e01099. http://dx.doi.org/10.14309/crj.0000000000001099.
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ABSTRACT Chronic liver pathologies may lead to vitamin A deficiency (VAD) through impairment of vitamin A absorption, storage, and distribution. VAD can contribute to ocular pathologies, and in the article, we present 2 patients with alcohol-associated cirrhosis admitted for liver transplant presenting with nonhealing central corneal epithelial defects in the eye without other known ocular pathologies. Low serum vitamin A levels were detected in both patients. Vitamin A supplementation eventually helped corneal epithelial healing within days/weeks. We suggest that VAD be screened for in all liver transplant candidates even before ocular symptoms present. This may prevent more severe VAD ocular sequelae.
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Matsunami, C., AF Hilton, JA Dyer, OW Rumbach, and IR Hardie. "Ocular complications in renal transplant patients." Australian and New Zealand Journal of Ophthalmology 22, no. 1 (1994): 53–57. http://dx.doi.org/10.1111/j.1442-9071.1994.tb01696.x.
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Asano, T., A. Tsuji, F. Nakajima, M. Hayakawa, and H. Nakamura. "Ocular hypertension in renal transplant recipients." Transplantation Proceedings 30, no. 7 (1998): 3904–5. http://dx.doi.org/10.1016/s0041-1345(98)01283-4.
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Qurban, Qirat, Zeeshan Kamil, and Khalid Mahmood. "Fornix Deepening by Using Amniotic Membrane Transplant." Annals of King Edward Medical University 27, no. 4 (2022): 503–7. http://dx.doi.org/10.21649/akemu.v27i4.4882.
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Objective: To assess the cosmetic outcomes of fornix deepening by using Amniotic membrane transplant in anophthalmic sockets in terms of good retention of ocular prosthesis. Abstract: Methods: This interventional case series was carried out at Khalid eye clinic, Karachi during the period of March 2019 to August 2019. Twenty-five patients belonging to either gender between the ages of 20 to 50 years were included, having anophthalmic sockets with fornix deformities incapable of retaining ocular prosthesis due to variable causes such as cicatrization, symblepharon, cyst, or poor conjunctival suturing technique following evisceration or enucleation. Amniotic membrane was transplanted following the division of bands, excision of cyst and release of adhesions. Pre and post fornix measurements were done and each patient was followed for a duration of six months after the operation to observe the cosmetic appearance and retention of ocular prosthesis. Results: Good cosmetic outcome with retention of ocular prosthesis was achieved in twenty-three (92%) cases, whereas two (8%) cases ended up in failure despite multiple surgeries. The mean pre-operative lower fornix depth was 3.8 ± 1.23 mm, which improved to 8.9 ± 1.10 mm (p- value < 0.001). None of the patients developed any infection or graft rejection. Conclusion: Fornix reconstruction in an anophthalmic socket is a challenging task, but a good cosmetic outcome can be achieved using amniotic membrane transplantation together with good oculoplastic surgical expertise.
Dissertations / Theses on the topic "Ocular transplant"
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Costa, Moya Daniel. "Crioconservación de córnea y esclera a -‐20°C en diferentes especies animales." Doctoral thesis, Universitat Autònoma de Barcelona, 2015. http://hdl.handle.net/10803/300735.
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Objetivo: Determinar la viabilidad y la seguridad microbiológica del tejido corneal y escleral canino [c] , felino [f] y equino [e] crioconservado a -20ºC, comparando tejidos crioconservados durante menos de 1 año (G≤1a) con aquellos crioconservados durante largos periodos de tiempo (G≥6a).
Materiales y métodos: Treinta y seis globos oculares de perro, 20 de gato, y 34 de caballo se obtuvieron de la Fundació Hospital ClínicVeterinari entre 2003 y 2013. Todos los animales estaban libres de neoplasias o enfermedades infecciosas y no presentaban alteraciones oculares. Tras un protocolo de descontaminación, los ojos se enuclearon en condiciones estériles antes de las 10 horas post-mortem. Los globos se almacenaron a -20ºC en condiciones atmosféricas con un antibiótico de amplio espectro y se mantuvieron a esa temperatura durante diferentes periodos de tiempo hasta su análisis. Se realizaron estudios microbiológicos, histológicos y ultraestructurales, tanto del tejido corneal como del escleral. La microbiología consistió en sembrar las muestras de córnea y esclera en agar sangre, McConkey y Sabouraud, y en caldo de cultivo cerebro-corazón. Histológicamente se evaluaron los artefactos de crioconservación y mediante microscopia electrónica de transmisión se analizó la integridad del colágeno, y se establecieron el número y las características de los queratocitos, clasificándolos en normales, apoptóticos y necróticos. En una selección de muestras caninas se comprobó la muerte celular por apoptosis mediante TUNEL.
Resultados. Microbiología: Los cultivos directos de los G≤1afueron positivos en un 27,5% [c], 15,0% [f] y 0% [e] y los de los G≥6a en un 0% [c], 0% [f] y 0% [e]. Los cultivos enriquecidos de los G≤1afueron positivos en un 47,5% [c], 30,0% [f] y 27,5% [e] y los de los G≥6a en un 16,7% [c], 0% [f] y 25,0% [e].
Histopatología:En las tres especies, los artefactos de crioconservación fueron más frecuentes en muestras G≥6a que en G≤1a. MET: El tipo de queratocito predominante fue el apoptótico en todas las muestras de las 3 especies. La estructura del colágeno se conservó a lo largo del tiempo, clasificándose como organizada o semiorganizada en todos los casos, excepto en una muestra de córnea canina.
Conclusión. El tejido corneal y escleral canino, felino y equino puede crioconservarse a -20ºC y utilizarse al menos durante 8, 10 y 9 años respectivamente sin impedimentos microbiológicos o estructurales. El paso del tiempo parece reducir la contaminación bacteriana en estos tejidos. La apoptosis es la vía de muerte celular más importante para los queratocitoscriocongelados a -20ºC.<br>Objective: To determine the viability and microbiological safety of canine [c], feline [f] and equine [e] corneal and scleral tissue cryopreserved at -20°C, comparing tissues cryopreserved for less than 1 year (G≤1a) with those cryopreserved for long periods (G≥6a).
Materials and Methods: Thirty-six eyeballs from dogs, 20 from cats, and 34 from horses were obtained from the Fundació Hospital Clinic Veterinari between 2003 and 2013. All animals were free of neoplasia or infectious diseases and had no ocular abnormalities. After a decontamination protocol, the eyes were enucleated under sterile conditions within 10 hours post-mortem and stored at -20°C under atmospheric conditions with a broad spectrum antibiotic until analysis. Microbiological, histological and ultrastructural studies of both, the scleral and corneal tissue were performed. Microbiology consisted on cultures of corneal and scleral samples on blood, McConkey and Sabouraud agar and brain heart broth. Cryopreservationartefacts were evaluatedby histology. Transmission electron microscopy (TEM) was used to establish collagen integrity, as well asthe number and characteristics of keratocytes, classifying those in normal, apoptotic and necrotic. Cell death by apoptosis was assessed by TUNEL in selected canine samples
Results.Microbiology: Direct cultures were positive in 27.5% [c] 15.0% [f] and 0% [e] of G≤1aand in none of the G≥6a.Enriched cultures were positive in 47.5% [c] 30.0% [f] and 27.5% [e] of G≤1aand in 16.7% [c] 0% [f] and 25.0% [e] ofG≥6a.Histopathology: In all three species, cryopreservation artefacts were more frequent in G≤1a samples than in G≥6a. TEM: The predominant keratocyte was apoptotic in all samples of the 3 species. Collagen structure is retained over time, classified as organized or semi-organized in all cases, except in one sample of canine cornea.
Conclusion. The canine, feline and equine corneal and scleral tissues cryopreserved at -20°C can be used for at least 8, 10 and 9 years respectively without microbiological or structural impediments. Bacterial contamination in these tissues seems to be reduced over time. Apoptosis is the most important cell death pathway for cryopreserved (-20º)keratocytes.
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Victer, Thayssa Neiva da Fonseca. "Aspectos epidemiológicos e morfológicos das córneas retiradas para transplantes no Distrito Federal/Brasil." reponame:Repositório Institucional da UnB, 2018. http://repositorio.unb.br/handle/10482/32553.
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Previous issue date: 2018-08-28<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ).<br>O programa de transplante de órgãos sólidos e tecidos do Brasil é um dos maiores do mundo. O transplante de córnea é o procedimento aplicado para tratamento para a maioria dos casos de cegueira, os quais estão relacionados a problemas na córnea. Os Bancos de Olhos possuem a função primordial na procura, captação, preservação e distribuição de córneas para fins de transplante e ao longo dos anos vêm buscando meios para aumentar a qualidade das córneas ofertadas. Existem vários fatores que podem influenciar no aspecto qualitativo da córnea como idade do doador, número das células endoteliais, além do tempo entre morte, enucleação e preservação do tecido. Visando a melhor qualidade das córneas ofertadas pelo Banco de Olhos do Distrito Federal, este trabalho caracterizou a influência morfológica ao longo do tempo na preservação dos tecidos oculares, causa mortis dos doadores e motivos para o descarte das córneas retiradas do banco para transplantes. Identificamos 1547 notificações de potenciais doadores resultando em um total de 3074 córneas doadas ao Banco de Olhos do DF. As características sócio demográficas demonstraram diferença entre gêneros (masculino, 74,8% e feminino, 25,2%), média de idade dos doadores foi de 40±15,9 anos. 25% das causas de morte foram por doenças cardiovasculares, seguido por 19,6% de perfuração por arma de fogo e 14,2% foram politraumatismos. Aproximadamente 60% (n=1836) foram transplantadas e 40% (n=1238) foram descartadas. Em relação às causas de descarte, 68% (n = 841) foram devidas a exames sorológicos positivos ou indeterminados e 39% (n = 486) por vencimento (período máximo garantido expirado de preservação da córnea). O tempo máximo de armazenamento conhecido para as córneas doadoras no meio de preservação Optisol-GS é limitado a 14 dias. Analisamos a morfologia de cada camada de 10 córneas preservadas em meio Optisol-GS, a 4 ° C, por microscopia especular em até 48 horas após a preservação e microscopia ótica, eletrônica de varredura e transmissão, com intervalos de preservação de 7, 10, 12, 14, 16 e 20 dias. Observamos discretas alterações morfológicas para as amostras do 10º dia e mais severas para o 14º, 16 º e 20º dias. Como as lamelas estromais incompactas, diminuição ou ausência de células epiteliais e do endotélio, descontinuidade do padrão hexagonal, ruptura do citoplasma e desorganização stromal. Também registramos a estrutura morfológica da camada de Dua em imagem de alta qualidade. Tecidos da córnea armazenados por mais de 10 dias não são apropriados para transplantes ópticos.<br>The Brazilian solid and tissue organ transplantation program is one of the largest in the world. Corneal transplantation is the procedure used to treat most of the cases of blindness, which are related to corneal impairment. The Eye Banks have the primary function in the search, capture, preservation and distribution of corneas for the purpose of transplantation and over the years have been looking for ways to increase the quality of the corneas offered. There are several factors that influence the qualitative aspect of the cornea such as donor age, number of endothelial cells, plus time between death, enucleation and tissue preservation. Aiming at the best quality of the corneas offered by the Bank of Eyes of the Federal District, this work characterized the morphological influence over time in the preservation of ocular tissues, donors causa mortis and reasons for the disposal of the corneas removed from the bank for transplants. We identified 1547 notifications of potential donors resulting in 3074 corneas donated to DF Eye Bank. The socio-demographic characteristics showed a difference between genders (male, 74.8% and female, 25.2%), mean age of the donors was 40 ± 15.9 years. 25% of the causes of death were due to cardiovascular diseases, followed by 19.6% of firearms and 14.2% were polytrauma. Approximately 60% (n = 1836) were transplanted and 40% (n = 1238) were discarded. Regarding the causes of discharge, 68% (n = 841) were due to positive or indeterminate serological tests and 39% (n = 486) by maturity (maximum guaranteed expired period of corneal preservation). The known maximum storage time for donor corneas in the Optisol-GS preservation medium is limited to 14 days. We analyzed the morphology of each layer of 10 corneas preserved in Optisol-GS medium, at 4 ° C, by specular microscopy up to 48 hours and optical and electronic scanning and transmission electron microscopy, with preservation intervals of 7, 10, 12, 14, 16 and 20 days. We observed discrete morphological changes for the samples of the 10th day and more severe for the 14th, 16th and 20th days. Like incompressed stromal lamellae, decreased or absent epithelial and endothelial cells, hexagonal pattern discontinuity, cytoplasmic rupture, and stromal disorganization. We also recorded the morphological structure of the Dua layer in high quality image. Corneal tissues stored for more than 10 days are not appropriate for optical transplants.
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Peres, Alessandro Afonso. "Hepatite B oculta em pacientes transplantados renais." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2004. http://hdl.handle.net/10183/8719.
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Introdução. Hepatite B oculta é caracterizada pela presença do HBV-DNA em pacientes que não expressam o antígeno B de superfície (HBsAg) e é relatada com maior freqüência em pacientes infectados pelo vírus da hepatite C (HCV). Nesse estudo avaliamos a prevalência de hepatite B oculta em transplantados renais infectados ou não pelo HCV e avaliamos a função hepática nos diferentes grupos. Material e métodos. Amostras de soro de 101 pacientes transplantados renais foram avaliadas para testes de função hepática, marcadores sorológicos e reação de polimerização em cadeia (PCR) para o HBV-DNA. Todos os pacientes eram HBsAg negativos e havia 51 pacientes anti- HCV reagentes e 50 pacientes não reagentes. A pesquisa do HBV-DNA foi feita por técnica de PCR aninhado para os genes S e “core”. Resultados. A pesquisa do gene S do HBV-DNA resultou positiva em 2 pacientes, sendo um do grupo anti-HCV reagente e o outro do grupo não reagente. A pesquisa do gene da região do “core” foi positiva em um paciente do grupo anti-HCV não reagente. A análise demonstrou que os pacientes do grupo anti-HCV reagente apresentam maior tempo de tratamento dialítico (50,8 + 34,6 e 32,02 + 20,87; p<0,001). Da mesma forma o grupo anti-HCV reagente apresentou valores mais elevados de aminotransferases: ALT: 34.5 ± 26.7 x 20.9 ± 10.0; (P < 0.001); AST: 31.7 ± 17.7 x 24.9 ± 14.9; (P < 0.05); gama glutamiltranspeptidase : 66.1 ± 82.4 x 33.4 ± 44.6; (P < 0.02) e fosfatase alcalina : 307.9 ± 397.7 x 186.9 ± 63.4; (P< 0.04). Os níveis de ciclosporina sérica também mais elevados também foram encontrados no grupo anti-HCV reagente 170.9 ± 69.8 and 135.0 ± 48.1 respectivamente (P < 0.02). No modelo de análise multivariada evidenciou-se que apenas a presença de infecção pelo HCV é determinante das alterações nas provas de função hepática. Conclusão. Hepatite B oculta foi um achado infreqüente na nossa população de pacientes transplantados renais, não tendo sido encontrada diferença na sua prevalência em pacientes infectados ou não pelo HCV. Pacientes anti-HCV reagentes apresentam alterações significativas das provas de função hepática e dos níveis sangüíneos de ciclosporina.<br>Background: Occult hepatitis B (HB) is characterized by the presence of HBV-DNA in patients who do not present HB surface antigen (HBsAg) detectable in sera. This condition is frequently described in patients with hepatitis C virus (HCV) infection and its clinical implications are uncertain. Since transplant patients were at risk for hepatitis B and/or C infection by blood transfusions, dialysis treatment and the transplant procedure itself we aimed to evaluate the prevalence of occult HB either with or without HCV infection. Patients and Methods: One hundred and one HBsAg negative renal transplant patients were evaluated. Fifty-one were anti-HCV reagents (Elisa III). Sera was analyzed for the presence of the S and core genes of the HBV-DNA by a nested PCR technique. Serological markers of HBV infection, liver function testes and ciclosporine through levels were also analysed. Results: The core gene of the HBV-DNA was identified in one HCV infected patient and in one anti-HCV negative who also presented the S gene (prevalence: 2% and 1% for each gene respectivelly). HCV infected patients presented longer pre-transplant dialysis time (50.8 ± 34.6 versus 32.0 ± 20.9; p<0,001). Results of liver function tests were also increased in the HCV infected group: ALT: 34.5 ± 26.7 x 20.9 ± 10.0; (P < 0.001); AST: 31.7 ± 17.7 x 24.9 ± 14.9; (P < 0.05); GGT: 66.1 ± 82.4 x 33.4 ± 44.6; (P < 0.02) and alkaline phosphatase: 307.9 ± 397.7 x 186.9 ± 63.4; (P< 0.04). Ciclosporine through levels were also significantly higher in HCV infected patients 170.9 ± 69.8 and 135.0 ± 48.1 respectivelly (P < 0.02). Multivariate analysis revealed that only HCV infection was determinant of the increased results of the LFTs. Conclusion: We found that occult hepatitis B is infrequent condition in our population of renal transplant patients and that HCV infection seems not to be a risk factor. In accordance with our previous work HCV we showed that infected renal transplant patients present evidence of liver damage and altered metabolism evidenced by the elevated liver function testes a higher ciclosporine through levels.
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Ito, Célia Regina Malveste. "A avaliação do efeito de antissépticos na superfície ocular e o papel da gentamicina no controle microbiano de córneas doadas." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/8115.
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Previous issue date: 2017-09-26<br>Decontamination of the surface of the donor eyeballs is part of the operational norms that eye banks advocate before preservation, and antisepsis procedures are effective, ensuring greater transplantation safety. The objective of the present study was to evaluate the antiseptic effect in reducing the microbiota of the ocular globe of donors of corneas prior to enucleation, with 5% povidone-iodine (PVP-I) and 0.05% chlorhexidine gluconate (GC), In the action times of 5, 10 and 15 minutes, as well as the susceptibility profile of the microbiota isolated from gentamicin. Thirty pairs of corneas received antiseptics, with PVP-I in the right eye and GC in the left, and for each time of action 10 pairs of eyeballs were used. Swabs were collected from the ocular surface before application of the solutions, after and at the time of preservation of the corneal tissue, to evaluate the reduction of the microbiota. After identification of the microbiota, an antibiogram test was performed with gentamicin. The data were computed and evaluated by Chi-square or Fisher's exact test, T-test and McNemar test paired, and the statistical significance level was 5% (p <0.05). In the second collection, after antisepsis, there was a reduction of 39,5% in the total of gram positive bacteria (G +), and of 76,5% in the gram negative (G-) bacteria, with no statistically significant difference (p = 0.183), which demonstrated that the bacterial elimination capacity of the antiseptics was similar. It was observed that, in the second collection, both were more effective for G-, with a statistically significant difference (p <0.001), than for G +, with no statistically significant difference (p = 0.494). In the third collection, after the residual effect of the antiseptics, there was a reduction of 99.1% of all the microorganisms. In the antibiogram test, 88% of the isolated microorganisms were sensitive to gentamicin. It was concluded that the use of antiseptics is essential for the effective decontamination of donated corneas prior to preservation. The residual time of the antiseptics increased the decontamination power of PVP-I and GC, being similar in reducing the microbiota of the ocular globe of the donor of corneas. Gentamycin contained in the cornea preservation medium complements the antisepsis of the donated tissues.<br>A descontaminação da superfície dos globos oculares doados são normas operacionais que os bancos de olhos preconizam antes da preservação e os procedimentos de antissepsia são eficazes, garantindo uma maior segurança ao transplante. O objetivo do presente estudo foi avaliar o efeito antisséptico na redução da microbiota do globo ocular de doadores de córneas antes da enucleação, com o povidona-iodo (PVP-I) a 5% e gluconato de clorexidina (GC) a 0,05%, nos tempos de ação de 5, 10 e 15 minutos, bem como o perfil de susceptibilidade da microbiota isolada à gentamicina. Trinta pares de córneas receberam antissépticos, sendo o PVP-I no olho direito e o GC no esquerdo, e para cada tempo de ação foram utilizados 10 pares de globos oculares. Foram colhidos swabs da superfície ocular antes da aplicação das soluções, após e no momento da preservação do tecido corneano, para avaliar a redução da microbiota. Após identificação da microbiota, foi realizado teste de antibiograma com gentamicina. Os dados foram computados e avaliados pelos testes Qui-Quadrado ou Exato de Fisher, teste T e Teste McNemar pareado, e o nível de significância estatística foi (p<0,05). Com relação aos dados obtidos na segunda coleta, após o uso de antissépticos, houve uma redução de 39,5% no total de bactérias gram positivas (G+) e de 76,5% nas gram negativas (G-), não havendo diferença estatística significativa (p=0,183), sendo semelhante a capacidade de eliminação bacteriana dos antissépticos. Observa-se que, na segunda coleta, ambos foram mais eficazes para as G-, com diferença estatisticamente significativa (p<0,001), do que para as G+, sem diferença estatisticamente significativa (p=0,494). Na terceira coleta, após o efeito residual dos antissépticos, houve redução de 99,1% de todos os micro-organismos. No teste de antibiograma, 88% dos micro-organismos isolados foram sensíveis à gentamicina. Concluiu-se que o uso de antissépticos é essencial para a efetiva descontaminação das córneas doadas antes da preservação. O tempo residual dos antissépticos aumentou o poder de descontaminação do PVP-I e GC, sendo semelhantes na redução da microbiota do globo ocular do doador de córneas. A gentamicina contida no meio de preservação de córnea complementa a antissepsia dos tecidos doados.
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Lima, Margarida Flor de. "Doença do enxerto versus hospedeiro ocular : um caso clínico." Master's thesis, 2015. http://hdl.handle.net/10451/25820.
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Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2015<br>A doença do enxerto versus hospedeiro (DEVH) é uma entidade que constitui um dos principais obstáculos ao transplante alogénico de células estaminais (TACE), sendo responsável pelo aumento da morbilidade e mortalidade a este associadas.
A DEVH ocorre quando as células T transplantadas do dador reagem contra antigénios histoincompatíveis do recetor, gerando diversas lesões tecidulares, em locais e com gravidade variáveis, mais comumente na pele, no trato gastrointestinal e no fígado. Menos frequentemente também atingem os sistemas hematopoiéticos, urinário e ocular.
A nível ocular manifesta-se essencialmente por queratoconjuntivite sicca (QCS), devido a fibrose e disfunção das glândulas lacrimal e de Meibómius, que conduzem à alteração do filme lacrimal. O diagnóstico de DEVH ocular dá-se pela presença de QCS agravada e sintomática juntamente com manifestações distintivas de DEVH em outro órgão. Se estas manifestações clínicas não forem atempadamente notadas, podem gerar complicações, como a perfuração ocular evidenciada no caso clínico descrito.
A terapêutica local é baseada na lubrificação, diminuição da inflamação, prevenção da evaporação e drenagem. No entanto, esta nem sempre é suficiente, tendo de se recorrer à terapêutica sistémica e, por vezes, cirúrgica.
Pelas repercussões que esta patologia poderá ter na qualidade de vida destes pacientes, torna-se assim muito importante o seguimento oftalmológico precoce pós-TACE.<br>The graft versus host disease (GVHD) constitutes one of the main obstacles to the allogeneic stem cell transplantation (ASCT), increasing the morbidity and mortality associated to this procedure.
GVHD occurs when the transplanted donor T cells react against histoincompatible recipient antigens, generating several tissue injuries in different places and with different clinical severity, affecting specially the skin, the gastrointestinal tract and the liver. Less frequently, it affects the haematopoietic, urinary and ocular systems.
The main ocular manifestation is keratoconjunctivis sicca (KCS), due to the fibrosis of the lacrimal glands and dysfunction of Meibómius glands, which induce tear film modification. The diagnosis of ocular GVHD is made by the presence of KCS aggravated or symptomatic along with distinctive manifestations of GVHD in another organ. If this manifestations are not adequately noted, they can generate complications, such as the ocular perforation verified in the described case report.
The local therapeutics is based on the ocular lubrication, decrease of the inflammatory process, evaporation prevention and drainage, although systemic or surgical interventions are sometimes needed.
Because of the consequences which this pathology might have in the patient’s quality of life, the early ophthalmological monitoring becomes very important post-ASCT.
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Silva, Teresa Patrícia Plancha da. "Paramiloidose ocular, um quadro de novo após transplante hepático : importãncia da semiologia na predição do risco de glaucoma." Master's thesis, 2014. http://hdl.handle.net/10451/24581.
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Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014<br>Familial amyloidotic polyneuropathy (FAP) type I is a form of hereditary amyloidosis, firstly described in Portugal, with an autosomic dominant trait, and variable penetrance. It’s characterized by extracellular deposition of amyloid substance in various organs, composed by mutated transthyretin, the protein involved in this type of FAP. Val30Met is its most frequent mutation. It’s a multissistemic disorder, predominantly with sensory-motor and autonomic neuropathy. As transthyretin is produced predominantly by the liver, the most common treatment is liver transplantation, allowing for neuropathy progression to be stopped. The mutated protein is also produced in the eye, and amyloid deposits can be found in various ocular tissues.Manifestations like vitreous opacities, glaucoma and pupillary disorders have been reported. After the liver transplantation, the independent ocular protein synthesis can lead to progression or development de novo of ophthalmological manifestations. A patient with FAP I, who developed glaucoma four years after liver transplantation will be presented, with findings at physical examination of amyloid deposition on the pupillary border and pupillary flower configuration, aspects described as predictive for the development of glaucoma. The importance of regular ophthalmological follow-up is emphasized, with special attention to its semiology.<br>A polineuropatia amiloidótica familiar (PAF) tipo I é uma amiloidose hereditária descrita primeiramente em Portugal, de transmissão autossómica dominante e penetrância variável. Caracteriza-se pelo depósito extracelular de substância amilóide em vários orgãos, composta por transtirretina mutada, a proteína envolvida neste subtipo de PAF, cuja mutação mais frequente é Val30Met. É uma doença multissistémica, com predomínio de polineuropatia sensitivo-motora e autonómica. Como a produção de transtirretina ocorre maioritariamente no fígado, o transplante hepático tem sido o tratamento mais utilizado, podendo travar a progressão da neuropatia. A proteína mutada é também produzida no olho e os depósitos de amilóide são encontrados em diversos tecidos oculares, estando descritas manifestações como opacidades vítreas, glaucoma e alterações pupilares. Após o transplante hepático, a síntese ocular autónoma da proteína pode conduzir à progressão ou aparecimento de novo das manifestações oftalmológicas. Será apresentado um doente com PAF I que desenvolveu glaucoma quatro anos após transplante hepático, com achados ao exame objectivo de depósitos de amilóide no bordo pupilar e configuração pupilar em flor, aspectos descritos como factores preditivos para o desenvolvimento de glaucoma. Enfatiza-se a importância de controlo oftalmológico regular da paramiloidose, com destaque para uma semiologia cuidada.
Book chapters on the topic "Ocular transplant"
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Lobo, Ann-Marie, Lucia Sobrin, and Marlene L. Durand. "Ocular Infections in Transplant Patients." In Principles and Practice of Transplant Infectious Diseases. Springer New York, 2019. http://dx.doi.org/10.1007/978-1-4939-9034-4_18.
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Pleyer, Uwe, and Anna-Karina Brigitte Maier. "Prevention and Treatment of Transplant Rejection in Keratoplasty." In Immune Modulation and Anti-Inflammatory Therapy in Ocular Disorders. Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-54350-0_6.
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Koutsikos, D., B. Agroyannis, G. Tserkezis, et al. "Ocular Findings in patients with successful renal transplantation." In Transplant International Official Journal of the European Society for Organ Transplantation. Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77423-2_26.
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Hoffer, B., P. Bickford-Wimer, M. Eriksdotter-Nilsson, et al. "Age-Related Changes in Rat Hippocampal Noradrenergic Transmission: Insights from In Oculo Transplants." In Neuronal Grafting and Alzheimer’s Disease. Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-48369-1_12.
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Tsubota, Kazuo, and Tetsuya Kawakita. "Autologous limbal transplant and allogenic limbal transplant." In Ocular Surface Disorders. Jaypee Brothers Medical Publishers (P) Ltd., 2013. http://dx.doi.org/10.5005/jp/books/12072_42.
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de Souza, Rodrigo G., Robert A. Britton, and Cintia S. de Paiva. "Fecal material transplant and ocular surface diseases." In Precision Medicine for Investigators, Practitioners and Providers. Elsevier, 2020. http://dx.doi.org/10.1016/b978-0-12-819178-1.00006-x.
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Guanting Qiu, Tina. "Understanding the Biology in Current Cell and Gene Therapy for Treating Macular Diseases." In Macular Diseases - An Update [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.1003722.
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The 21st century ushers us into an information explosive era in modern medicine development. At the cusp of biology and technology convergence, significant advances are being made in the strategic approach toward preventing and treating retinal degeneration and neovascular diseases, in particular of a restoration of macular vision, from new surgical interventions to emerging pharmacotherapies through minimally invasive ocular drug delivery and genetic bio factory, and rapidly evolving retinal gene therapies and cell transplant, which are changing the landscape of retinal therapeutic horizon. Understanding disease physio pathological processes is becoming ever more important for developing and delivering these therapeutic modalities to individual patients with precision; in the light of cell & gene therapy, host-donor interplay is of strategic importance.
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"Extra-Temporal Facial Nerve Reconstruction." In Diagnostic Techniques and Therapeutic Strategies for Parotid Gland Disorders. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-5603-0.ch018.
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Hypoglossal-facial anastomosis (HFA) as an end-to-end anastomosis (EEA) has several advantages, and indirect HFA with interposition graft is a safe and excellent method. The extended HFA is the method of choice for all malignant tumors that require extensive resection of the facial plexus, especially when combined with a neck dissection. Facio-facial anastomosis combined with HFA leads to excellent results when resection defect is restricted to the central portion of the facial plexus. Good functional rehabilitation of the musculature of the oral sphincter system is achieved using the hypoglossal nerve. To innervate the musculature of the ocular sphincter system, a facio-facial anastomosis between the nerve trunk and the cranial nerve branches is made using a free nerve transplant. Dynamic reanimation involves nerve repair, nerve transfer, regional muscle transfer, or free-muscle transfer. Dynamic reconstructive techniques can yield improved facial symmetry, spontaneous and symmetrical smile, eye closure and protection, and oral competence.
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Mynlieff, Michelle, and Thomas V. Dunwiddie. "In Vitro Electrophysiological Analysis of in Oculo Transplants." In Methods in Neurosciences. Elsevier, 1991. http://dx.doi.org/10.1016/b978-0-12-185263-4.50034-0.
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Sharma, Ashok. "Cultured Limbal Stem Cell Transplants in Ocular Surface Diseases: Our Experience and Review of Literature." In Surgical Techniques in Ophthalmology: Corneal Surgery. Jaypee Brothers Medical Publishers (P) Ltd., 2010. http://dx.doi.org/10.5005/jp/books/11369_44.
Full textConference papers on the topic "Ocular transplant"
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Almeida, Ana Laura Carvalho, Paula Lorraynne Vinhal, Giovana Rodrigues Batista, et al. "CYTOMEGALOVIRUS AS A CAUSAL FACTOR IN ANTERIOR UVEITIS." In I Congresso Internacional Multidisciplinar (I CIM). New Science Publishers, 2024. http://dx.doi.org/10.56238/i-cim-019.
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Cytomegalovirus (CMV) is a virus of the Herpesviridae family, widely disseminated in the world population. It is estimated that up to 80% of individuals carry the virus, which can remain latent for years, being reactivated mainly in conditions of immunosuppression. CMV is a major cause of congenital and opportunistic infections in immunocompromised patients, particularly in individuals with HIV/AIDS, transplant recipients and patients undergoing immunosuppressive treatments. Although CMV infection is, in most cases, asymptomatic or mild in immunocompetent individuals, it can manifest in immunocompromised individuals or when the virus is reactivated and affect several organs, including the eyes, causing serious ocular complications such as anterior uveitis. (CARMICHAEL, 2011).
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Santos, André Luiz dos. "COMPREENDENDO A IMUNOLOGIA NOS TRANSPLANTES DE TECIDOS OFTALMOLÓGICOS." In II Congresso Brasileiro de Biologia Molecular On-line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/2333.
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Introdução: O transplante de órgãos, um dos maiores avanços da medicina, se tornou popular, sendo mais comum para córneas, envolvendo a substituição, completo (penetrante) ou parcial (lamelar ou profundo) da córnea doente. A esperada eficácia do transplante é quase sempre alcançada, devendo aos cuidados tanto com doador quanto receptor, relevando da rejeição do tecido até os cuidados após intervenção. Objetivo: Compreender a importância da imunologia para os transplantes de tecidos oftalmológicos. Materiais e Métodos: Pesquisa bibliográfica digital, no google academic, combinando os termos transplantes, imunogenética e córnea. Resultados: A rejeição do transplante é processo imunológico de descompensação da córnea transplantada. A principal razão para o bom efeito está no privilégio da córnea, devido ao viés imunológico que ocorre no segmento anterior, abreviado ACAID (Anterior Chamber Associated Immune Deviation), que perde sua eficiência num processo inflamatório, aumentando o número de células de Langerhans e a expressão de antígenos classe I e II do complexo principal de histocompatibilidade, aumentando citocinas pró-inflamatórias oculares, provocando neovascularização da córnea. A perda do privilégio imunológico é acompanhada de rejeição, e seu mecanismo pode ser dividido em três etapas: (a) Rejeição do braço aferente - reconhecer o sistema imunológico de antígenos heterólogos como principal componente da rejeição do braço aferente. As células de Langerhans são um fator chave nesse processo, pois além de estimular os linfócitos B e T, processam e apresentam antígenos ao sistema imunológico; (b) Estágio central da rejeição - reconhecer um antígeno como heterólogo ativa os linfócitos T imaturos para proliferar e realizar a expansão clonal; (c) Braço eferente da rejeição - reação eferente da rejeição do transplante de córnea, mediada por células e nenhum anticorpo envolvido. As principais células que comandam a destruição do enxerto são os linfócitos T CD4+, que recrutam outras células efetoras: macrófagos, leucócitos polimorfonucleares e linfócitos NK (natural killer), que liberam citocinas, como o fator de necrose tumoral, destruindo células do doador. Conclusão: O endotélio com capacidade de replicação limitada é a razão do insucesso do transplante do doador. A compreensão dos aspectos imunológicos da rejeição, as manifestações clínicas e a classificação da rejeição são fundamentais aos oftalmologistas na personalização do tratamento.
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Santos, André Luiz Dos. "PATOLOGIAS OFTALMOLÓGICAS CAUSADAS POR AFECÇÕES MICROBIANAS IMPLICAM EM TRANSPLANTES." In I Congresso Nacional de Microbiologia Clínica On-Line. Revista Multidisciplinar em Saúde, 2021. http://dx.doi.org/10.51161/rems/1165.
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Introdução: A presente pesquisa trata de destacar as principais infecções provocadas por vírus, bactérias ou fungos que causam doenças no globo ocular ou tecidos circunvizinhos podem levar a cegueira necessitando de tratamentos agressivos e muitos casos de procedimento de transplantes de córneas. Objetivo: Caracterizar infecções provocadas por microorganismos que causam patologias oculares que levam a necessidade de transplantes. Material e métodos: através de leitura criteriosa foram selecionados alguns artigos científicos na plataforma scielo que se destacaram por tratarem de afecções oftalmológicas microbianas capazes de levar a cegueira. Resultados: Verifica-se que não são poucas, nem são raras as patologias relacionadas ao globo ocular que podem levar a cegueira, seja pela impossibilidade de detecção da infecção, seja pelo tratamento necessariamente agressivo ou pela evolução da doença. Algumas doenças, organizadas por ordem alfabética são: a) Blefarite bacteriana: x; b) Ceratite Acanthamoeba: provocado por um protozoário do gênero Acanthamoeba, pode levar a úlceras da córnea e eventual perda de visão; c) Ceratite fúngica: A maioria dos casos de ceratite fúngica, em todo o mundo, é causada por fungos filamentosos septados não pigmentados. Muitos casos podem progredir para infecção fulminante e alguns pacientes perdem a sua visão por culpa do necessário tratamento agressivo; d) Ceratite herpética: Os vírus herpes simples é o vírus causador. A doença corneana decorrente dessa infecção apresenta múltiplas manifestações; e) Conjuntivites: patologias inflamatórias que afetam o tecido conjuntivo que protege o globo ocular do meio externo, observando-se dilatação vascular, infiltração celular e exsudação. As conjuntivites têm origens virais ou bacterianas; f) Endoftalmite: apresenta infecção grave intraocular, afetando humor aquoso, humor vítreo, ou ambos, e ameaça severamente a visão. A Candida albicans é o agente etiológico mais comum; g) Tracoma: infecção causada pela bactéria Chlamydia trachomatis, uma das maiores causas de cegueira infecciosa evitável do mundo. Conclusão: As patologias oftalmológicas provocadas por microorganismos, quando não devidamente tratadas, levam a perda de visão.
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Rubin, Francis Spiegel, Adriana Alvim, and Carlos Mello. "Uma solução de aprendizagem de máquina para detecção de ceratocone." In Simpósio Brasileiro de Sistemas de Informação. Sociedade Brasileira de Computação (SBC), 2020. http://dx.doi.org/10.5753/sbsi.2020.13120.
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Ceratocone é um problema que provoca alterações no formato e espessura da córnea, deixando-a mais fina e menos resistente. Pacientes que foram submetidos a cirurgia refrativa a laser tem uma chance maior de desenvolver a doença pelo afinamento corneano, podendo causar cegueira e exigir o transplante de córnea. Este artigo apresenta uma proposta para detectar estágios iniciais de ceratocone em pacientes candidatos a cirurgia refrativa, aplicando algoritmos de aprendizagem de máquina em dados oculares e biomecânicos da córnea de forma a diferenciar córneas normais de portadores de ceratocone.