Showing of 1 until 13 from 165 result(s)
Search for: Epithelium, corneal; Limbus corneae; Stem cells transplantation; Amnion; Case reports
Abstract
Objetivo: Avaliar o perfil clínico e epidemiológico dos transplantes de córnea realizados em um centro de referência oftalmológica de Recife no estado de Pernambuco, localizado no nordeste do Brasil.
Métodos: Esse estudo transversal coletou através de prontuários médicos dados clínicos e epidemiológicos de pacientes submetidos a ceratoplastia na Fundação Altino Ventura, de janeiro a dezembro de 2017.
Resultados: Um total de 356 procedimentos foram realizados em 327 pacientes dos quais 165 (50.5%) eram mulheres. A média de idade na cirurgia foi de 50.9 ± 22.6 anos (variação, 10 - 89 anos). A maioria dos pacientes (n=152 [46.5%]) era da capital e região metropolitana. A média de tempo de espera na fila para o transplante de córnea foi de 52.4 ± 58.9 dias (variação, 0 - 460 dias). As principais indicações de transplante foram ceratite infecciosa (n=88 [24.7%]), ceratocone (n=80 [22.5%]) e falência de transplante prévio (n=75 [21.1%]). Transplante penetrante foi a técnica mais realizada (n=213 [59.9%]) e foi mais comum em homens (n=132 [76.7%]), enquanto os transplantes lamelares posteriores (n=143 [41.1%]) foram mais realizados nas mulheres (p<0.001).
Conclusão: Ceratites infecciosas foram a causa mais comum de transplante, com prevalência similar em adultos economicamente ativos de ambos os sexos. Transplante penetrantes foram os prevalentes em homens e os transplantes lamelares em mulheres.
Keywords: Doença da córnea/epidemiologia; Transplante de córnea; Ceratoplastia penetrante; Brasil/epidemiologia
Abstract
MÉTODOS: Córneas humanas de treinamento disponibilizadas foram randomizadas em quatro grupos: Pachy-100 (profundidade de incisão = espessura corneana central - margem de segurança de 100 µm), Pachy-50 (margem de segurança de 50 µm), Pachy-0 (sem margem de segurança) e Pachy+50 (profundidade de incisão = espessura corneana central + 50 µm). Todas as lamelas foram dissecadas através um método padronizado e já publicado (Pachy-DSEK). As espessuras das lamelas (centro, zona de 3,0mm e zona de 6,0mm) foram medidas com tomografia de coerência óptica. A razão de espessura centro-periferia foi calculada aos 3,0 e 6,0 mm de diâmetro.
RESULTADOS: Perfuração endotelial ocorreu apenas no grupo Pachy+50 (n=3, 30%). A espessura central da lamela nos grupos Pachy-100, Pachy-50, Pachy-0 e Pachy+50 foi de 185 ± 42 µm, 122 ± 29 µm, 114 ± 29 µm, e 58 ± 31 µm, respectivamente (p<0,001). As razões C/P aos 3,0 e 6,0 mm foram de 0,97 ± 0,06 e 0,92 ± 0,14, respectivamente. Os parâmetros de características do doador não se correlacionaram com os resultados de espessura de lamela. A profundidade planejada de incisão se correlacionou com a maioria dos parâmetros de espessura de lamela (p<0,001). A espessura de lamela se correlacionou negativamente com a profundidade planejada da incisão (p<0.001, r=-0,580). O melhor resultado foi observado no grupo Pachy-0, em que 75% das lamelas mediram abaixo de 130 µm e não houve perfuração endotelial.
CONCLUSÃO: Através de um método padronizado de dissecção, a maioria das lamelas endoteliais apresentou uma configuração planar. O planejamento de profundidade de incisão igual à espessura corneana central resultou em alta porcentagem de lamelas ultrafinas sem ocorrência de perfuração.
Keywords: Transplante de córnea; Ceratoplastia lamelar; Endotélio corneano; Dissecção; Tomografia de coerência óptica
Abstract
PURPOSE: This study was conducted to investigate the effect of injectable platelet-rich fibrin on the recovery of compromised epithelium due to crosslinking treatment.
METHODS: In this comparative study, the epithelial closure rates and in vivo confocal biomicroscopy results of 26 patients with keratoconus who underwent subconjunctival injection of injectable platelet-rich fibrin near the limbus after epithelium-off corneal crosslinking treatment were compared with those of 25 patients who did not receive the injection of injectable platelet-rich fibrin.
RESULTS: The average time to epithelial defect closure in the injectable platelet-rich fibrin group was 2.76 ± 0.90 days compared to 3.56 ± 0.86 days in the non-injectable platelet-rich fibrin group (p=0.003). At the end of the 1st month, the mean subbasal nerve plexus density was 1.26 ± 1.61 nerves/mm2 in the injectable platelet-rich fibrin group, whereas it was 0.72 ± 0.89 nerves/mm2 in the non-injectable platelet-rich fibrin group (p=0.016). By the 3rd month, the density increased to 3.42 ± 1.13 nerves/mm2 in the injectable platelet-rich fibrin group and 2.36 ± 1.15 nerves/mm2 in the non-injectable platelet-rich fibrin group (p=0.002). Similarly, the anterior stromal keratocyte density at the end of the 1st month was 93.6 ± 33.5 cells/mm2 in the injectable platelet-rich fibrin group compared to 67.3 ± 26.4 cells/mm2 in the non-injectable platelet-rich fibrin group (p=0.001). By the end of the 3rd month, the density increased to 255.2 ± 45.7 cells/mm2 in the injectable platelet-rich fibrin group and 222.1 ± 43.6 cells/mm2 in the non-injectable platelet-rich fibrin group (p=0.011). In the non-injectable platelet-rich fibrin group, one patient developed a sterile infiltrate at the end of the 1st week, whereas no complications were observed in the injectable platelet-rich fibrin group.
CONCLUSION: Subconjunctival injectable platelet-rich fibrin application is an effective and safe method for corneal epithelial healing after crosslinking treatment.
Keywords: Keratoconus; Platelet-rich fibrin; Epithelium; corneal; Corneal crosslinking; Wound healing
Abstract
PURPOSE: To investigate the association of pre-photorefractive keratectomy Schirmer-1 test value with post-photorefractive keratectomy central corneal epithelial thickness, ocular surface disease index score, and uncorrected distance visual acuity.
METHODS: Patients were categorized according to preoperative Schirmer-1 value: the normal Schirmer Group (n=54; Schirmer-1 test value, >10 mm) and the low Schirmer Group (n=52; Schirmer-1 test value, between 6 and 10 mm). We analyzed ablation depth, visual acuity, result of Schirmer-1 test (with anesthesia), tear film break-up time, ocular surface disease index score, central corneal epithelial thickness, and spherical equivalent refraction.
RESULTS: We found significant differences between the groups in Schirmer-1 test value, tear film break-up time, and ocular surface disease index score, both preoperatively and postoperatively (p<0.001). The preoperative central corneal epithelial thicknesses of the two groups were similar (p>0.05). After photorefractive keratectomy, the Schirmer-1 test value and spherical equivalent refraction decreased in both groups (p<0.05), and ocular surface disease index scores and central corneal epithelial thickness values increased in the low Schirmer Group (p<0.001) but not in the normal Schirmer Group (p>0.05). The postoperative central corneal epithelial thicknesses of the low Schirmer Group were significantly higher than those of the normal Schirmer Group (p<0.001). Postoperative uncorrected distance visual acuity did not differ significantly between the two groups (p>0.05).
CONCLUSIONS: In patients with low Schirmer-1 test values before photorefractive keratectomy, the corneal epithelium thickened and ocular surface complaints increased during the postoperative period. However, changes in the corneal epithelium did not affect the postoperative uncorrected distance visual acuity. To reduce postoperative problems on the ocular surface in these patients, we recommend that dry eye be treated before photorefractive keratectomy.
Keywords: Epithelium, corneal; Cornea; Photorefractive keratectomy; Schirmer test; Visual acuity
Abstract
PURPOSES: This study aims to assess and compare the postoperative visual and topographic outcomes, complications, and graft survival rates following deep anterior lamellar keratoplasty and penetrating keratoplasty in patients with macular corneal dystrophy.
METHODS: In this study we enrolled 59 patients (23 male; and 36 female) with macular corneal dystrophy comprising 81 eyes. Out of these, 64 eyes underwent penetrating keratoplasty, while 17 eyes underwent deep anterior lamellar keratoplasty. The two groups were analyzed and compared based on best-corrected visual acuity, corneal tomography parameters, pachymetry, complication rates, and graft survival rates.
RESULTS: After 12 months, 70.6% of the patients who underwent deep anterior lamellar keratoplasty (DALK) and 75% of those who had penetrating keratoplasty (PK) achieved a best-corrected visual acuity of 20/40 or better (p=0.712). Following surgery, DALK group showed lower front Kmean (p=0.037), and Q values (p<0.01) compared to the PK group. Postoperative interface opacity was observed in seven eyes (41.2%) in the DALK group. Other topography values and other complications (graft rejection, graft failure, cataract, glaucoma, microbial keratitis, optic atrophy) did not show significant differences between the two groups. The need for regrafting was 9.4% and 11.8% in the PK and DALK groups, respectively (p=0.769). Graft survival rates were 87.5% and 88.2% for PK and DALK; respectively (p=0.88 by Log-rank test).
CONCLUSION: Both PK and DALK are equally effective in treating macular corneal dystrophy, showing similar visual, topographic, and survival outcomes. Although interface opacity occurs more frequently after DALK the visual results were comparable in both groups. Therefore, DALK emerges as a viable surgical choice for patients with macular corneal dystrophy without Descemet membrane involvement is absent.
Keywords: Macular corneal dystrophy; Corneal dystrophies; Hereditary; Keratoplasty; Penetrating; Corneal transplantation
Abstract
PURPOSE: To assess the outcomes of deep anterior lamellar keratoplasty or penetrating keratoplasty at the scar and the edema stages.
METHODS: Forty-five patients (45 eyes) with keratoconus scar stage (scar group, n=26; penetrating keratoplasty a subgroup, n=7; deep anterior lamellar keratoplasty b subgroup, n=19) and keratoconus edema stage (edema group, n=19; penetrating keratoplasty c subgroup, n=12; deep anterior lamellar keratoplasty d group, n=7) who received penetrating keratoplasty or deep anterior lamellar keratoplasty from 2000 to 2022 were retrospectively studied. At 1, 6, and 12 months after surgery, the best-corrected visual acuity, astigmatism, spherical equivalent, corneal endothelial cell density, and complications were analyzed.
RESULTS: The best-corrected visual acuity and average corneal endothelial cell loss rate were not significantly different between the scar and edema groups (p>0.05). At 6 and 12 months after surgery, the astigmatism and spherical equivalent in the scar group were significantly lower than those in the edema group (p<0.05). The spherical equivalent of the deep anterior lamellar keratoplasty b subgroup was lower than that of the penetrating keratoplasty a subgroup in the scar group 6 months after surgery (p<0.05). In the edema group, there was no significant difference in spherical equivalent between subgroups (p>0.05). There were no significant differences in best-corrected visual acuity and astigmatism between subgroups within the two groups (p>0.05). In comparison to the scar group, the edema group experienced more complications. According to a survival analysis, there was no statistically significant difference between the scar group and the edema group regarding the progression of vision.
CONCLUSIONS: In terms of the outcomes and prognosis for vision after keratoplasty with edema stage and scar stage, deep anterior lamellar keratoplasty may be as effective as penetrating keratoplasty.
Keywords: keratoconus; Edema; Cicatrix; keratoplasty, penetrating; Corneal transplantation; Astigmatism; Corneal endothelial cell loss; Endothelial cells
Abstract
OBJETIVOS: Foram estudadas cinco técnicas de cultivo primário de células epiteliais de córnea humana para se determinar o melhor protocolo para a obtenção do maior rendimento de meio de cultivo condicionado para ser utilizado na diferenciação de células tronco mesenquimais para células epiteliais de córnea.
MÉTODOS: As técnicas de cultivo estudadas foram: explantes em frascos de cultivo com e sem tratamento hidrofílico de superfície, sobre membrana amniótica, com digestão enzimática e por raspado de córnea. O meio de cultivo condicionado foi coletado e as células tronco mesenquimais induzidas a se diferenciarem em células epiteliais da córnea utilizando o meio de cultivo condicionado. As células foram caracterizadas por citometria de fluxo com pan-citoqueratina e com os marcadores específicos da córnea, citoqueratina 3 e citoqueratina 12.
RESULTADOS: A técnica utilizando frascos com o tratamento de superfície apresentou o maior rendimento de meio de cultivo condicionado. Os frascos sem tratamento de superfície levaram a uma taxa de sucesso muito baixa. A digestão enzimática e a raspagem da córnea mostraram contaminação das culturas com fibroblastos de córnea. A cultura sobre membranas amnióticas só permitiu a coleta do meio de cultivo condicionado durante a 1ª confluência celular. A análise de citometria de fluxo confirmou o sucesso da diferenciação celular utilizando o meio de cultivo condicionado coletado, demonstrada pela expressão de citoqueratina 3 (95,3%), citoqueratina 12 (93,4%) e pan-citoqueratina (95,3%).
CONCLUSÃO: O cultivo de explantes de células tronco mesenquimais em frascos com tratamento hidrofílico de superfície é a melhor técnica para a obtenção de um alto rendimento de meio de cultivo condicionado.
Keywords: Cultivo de células; Células tronco mesenquimais; Diferenciação celular; Células epiteliais; Córnea; Meio de cultivo condicionado; Técnicas de cultivo
Abstract
PURPOSE: Wet bio-amniotic membrane plugging combined with transplantation is a novel option that combined amniotic membrane plugging with amniotic membrane transplantation for the treatment of small corneal perforations. This study aimed to evaluate the efficacy of wet bio-amniotic membrane plugging in the treatment of small corneal perforations and compared it with that of the penetrating keratoplasty procedure.
METHODS: Forty patients (41 eyes) with small corneal perforations <3 mm in diameter treated at our hospital between July 2018 and January 2021 were retrospectively included. Among them, 21 eyes were treated with wet bio-amniotic membrane plugging (wet bio-amniotic membrane plugging group), and 20 eyes were treated with penetrating keratoplasty procedure (penetrating keratoplasty procedure group). The best-corrected visual acuity, anterior chamber formation, corneal thickness, primary disease control, postoperative complications, and graft survival rate were assessed.
RESULTS: No significant difference in baseline characteristics was found between the wet bio-amniotic membrane plugging and penetrating keratoplasty procedure groups (p>0.05). The postoperative control rates of primary diseases in the wet bio-amniotic membrane plugging and penetrating keratoplasty procedure groups were 95.2% and 90.0%, respectively (p=0.481). Visual acuity was improved 6 months after the operation in the wet bio-amniotic membrane plugging group and was improved at postoperative 1 month in the penetrating keratoplasty procedure group. The formation time of the anterior chamber in the wet bio-amniotic membrane plugging group was significantly shorter than that in the penetrating keratoplasty procedure group (p=0.023). The corneal thickness of the two groups significantly increased 12 months after the operation; however, the degree of thickening in the penetrating keratoplasty procedure group was higher than that in the wet bio-amniotic membrane plugging group (p<0.001). During the follow-up, postoperative complications were not different between the two groups (p>0.999).
CONCLUSION: The results suggest that wet bio-amniotic membrane plugging is effective and safe in the treatment of small corneal perforations. Thus, it can be used as an emergency treatment alternative to penetrating keratoplasty procedure for small corneal perforations.
Keywords: Amnion; Transplantation; Amniotic membrane; Keratoplasty, penetrating; Corneal perforation; Wet bio-amniotic membrane plugging; Wet bio-amniotic membrane transplantation
Abstract
PURPOSE: To evaluate the clinical results of cryopreserved amniotic membrane transplantation as a treatment option for refractory neurotrophic corneal ulcers.
METHODS: This prospective study included 11 eyes of 11 patients who underwent amniotic membrane transplantation for the treatment of refractory neurotrophic corneal ulcers at Hospital de Clínicas da Universidade Federal do Paraná, in the city of Curitiba, from May 2015 to July 2021. Patients underwent different surgical techniques in which the amniotic membrane was applied with the epithelium facing upward to promote corneal re-epithelialization.
RESULTS: The median age of the patients was 60 years (range, 34-82 years), and 64% were men. The predominant etiology of corneal ulcers was herpes zoster (45% of cases). Approximately one-third of the patients (27%) were chronically using hypotensive eye drops, and more than half (54%) had previously undergone penetrating corneal transplantation. At the time of amniotic membrane transplantation, 18% of the eyes had corneal melting, 9% had corneal perforation, and the others had corneal ulceration without other associated complications (73%). The time between clinical diagnosis and surgical treatment ranged from 9 days to 2 years. The corrected visual acuity was worse than 20/400 in 90% of the patients preoperatively, with improvement in 36% after 3 months of the procedure, worsening in 18% and remaining stable in 36%. Of the patients, 81% complained of preoperative pain, and 66% of them reported total symptom relief after the surgical procedure. In one month, 54.6% of the patients presented a closure of epithelial defect, and half of the total group evolved with corneal thinning. The failure rate was 45.5% of the cases.
CONCLUSION: Cryopreserved amniotic membrane transplantation can be considered a good alternative for treating refractory neurotrophic corneal ulcers, as it resulted in significant improvement in pain (66%) and complete epithelial closure (60%) in many patients at 1 month postoperatively. Notably, the high failure rate highlights the need for further studies to identify patient- and ulcer-related factors that may influence the outcomes of this procedure.
Keywords: Amnion/transplantation; Corneal ulcer; Anterior eye segment; Keratitis
Abstract
Este relato de caso descreve as características clínicas e o manejo cirúrgico de um paciente que teve perfuração da córnea devido à enoftalmia grave consistente com a “síndrome do cérebro silencioso”. Um homem de 27 anos com história de hidrocefalia congênita e derivação ventrículo-peritoneal foi encaminhado com queixas de “afundamento dos globos oculares” e diminuição progressiva da visão no olho esquerdo. O exame revelou enoftalmo bilateral importante, além de perfuração superonasal da córnea com prolapso iriano no olho esquerdo. A paciente foi submetida à ceratoplastia terapêutica no dia seguinte. Foi realizado no mês seguinte a reconstrução da órbita com enxerto costocondral e revisão do shunt para evitar progressão e piora do caso.
Keywords: Enoftalmia; Perfuração da córnea; Hidrocefalia; Derivação ventriculoperitoneal; Ceratoplastia penetrante; Órbita/transplante; Humanos; Relato de caso
Abstract
O presente trabalho traz uma revisão das abordagens terapêuticas para a cegueira da córnea. O estudo detalha as etapas e os elementos envolvidos na cicatrização da córnea. Ele mostra as limitações das estratégias cirúrgicas e farmacológicas usadas para restaurar e manter a transparência da córnea em termos de sobrevida a longo prazo e alcance geográfico. As perspectivas dos agentes anabólicos, incluindo vitamina A, hormônios, fatores de crescimento e novos moduladores pró-mitóticos e anti-inflamatórios para auxiliar a cicatrização da ferida na córnea, são revisadas criticamente. Aqui, apresentamos estudos envolvendo nanotecnologia, terapia gênica e reengenharia de tecidos como possíveis estratégias futuras para atuar de maneira isolada ou combinada com a cirurgia da córnea para prevenir ou reverter a cegueira corneana.
Keywords: Cegueira; Doenças da córnea; Transplante de córnea; Terapia genética; Terapia baseada em transplante de células e tecidos; Células-tronco
Abstract
This study aimed to evaluate the efficacy and safety of topical losartan for treating corneal injuries and stromal fibrosis based on preclinical and clinical evidence. A systematic search was conducted in October 2024 following PRISMA guidelines across Embase, PubMed, Web of Science, and the Cochrane Library. Studies assessing topical losartan use in animal models or human patients with corneal injury were included. No randomized clinical trials were identified. Of 750 articles screened, 12 met the inclusion criteria – seven preclinical studies and five case reports. Preclinical evidence indicated that topical losartan at 0.2-0.8 mg/dL reduced stromal opacity and myofibroblast differentiation. Higher concentrations (8-80 mg/dL) offered no additional benefit and were associated with ocular surface irritation. The five case reports included 11 patients (12 eyes); eight eyes showed visual improvement, and no adverse effects were observed at a dose of 0.8 mg/dL. Topical losartan demonstrates potential as an antifibrotic agent for corneal injuries. However, variability in outcomes and dose-related toxicity at higher concentrations highlight the need for controlled clinical trials to confirm efficacy, establish optimal dosing, and ensure safety.
Keywords: Cornea; Epithelial cells; Myofibroblasts; Corneal opacity; Losartan
Abstract
A falência primária do enxerto é uma complicação conhecida que pode ocorrer após o transplante penetrante de córnea. O tratamento usual dessa complicação é com um novo transplante penetrante. Apresentamos um caso em que foi usado o transplante endotelial de membrana de Descemet (DMEK - do inglês Descemet membrane endothelial keratoplasty) para o tratamento da falência primária após o transplante penetrante. Uma paciente submetida a transplante penetrante evoluiu com falência primária do enxerto a despeito do uso intenso de corticoide tópico e uma prova terapêutica de antivirais. Três meses após a cirurgia inicial, foi optado pela realização do transplante endotelial de membrana de Descemet sob o transplante penetrante. Houve um clareamento precoce e progressivo do enxerto com melhora importante da visão. Após um mês, a visão sem correção era de 20/40 melhorando para 20/20 com refração. O transplante endotelial de membrana de Descemet pode ser uma alternativa a um novo transplante penetrante como tratamento da falência primária.
Keywords: Doenças da córnea; Transplante da córnea/efeitos adversos; Rejeição do enxerto; Ceratoplastia penetrante; Lâmina limitante posterior; Ceratoplastia endotelial com remoção da lâmina limitante posterior; Infecções oculares virais; Humanos; Relatos de casos
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