Susceptibilidad de las mucosas oculares al SARS COV-2: bioseguridad sanitaria / Susceptibility of eye mucosa to SARS CoV-2: sanitary biosecurity

RESUMEN: El SARS CoV-2, agente causal de la enfermedad llamada Covid-19, infecta las mucosas digestivas y respiratorias, afectando las células epiteliales. El virus ingresa a través del receptor de membrana ACE2 provocando la disrupción de la homeostasis celular. Frecuentes reportes indican la presencia de conjuntivitis ocular en pacientes diagnosticadas con Covid-19, lo cual ha alertado a los científicos sobre el potencial foco de infección viral de las secresiones lagrimales.Los epitelios de la conjuntiva ocular sub-palpebral y corneal, se caracterizan por presentar el receptor de la enzima convertidora de angiotensina 2 (ACE2) y proteasa transmembrana asociada serina 2 (TMPRSS2), cuya interacción activa los mecanismos de liberación de citoquinas, capaces de instalar un proceso de conjuntivitis infecciosa por SARS CoV-2, pero no necesariamente hacer extensiva la infección hacia los sistemas digestivo y respiratorio.Aunque este proceso inflamatorio es más frecuente como una expresión de la infección general y más grave. Sin embargo, cualquiera sea la vía de infección o ingreso del virus SARS CoV-2 es importante considerar el riesgo de infectividad de las lágrimas y las secresiones conjuntivales en los pacientes. Este estudio pretende llamar la atención sobre las medidas de cuidados y control sanitario, incorporando mejores normas de protección personal y bioseguridad, especialmente en el áreas de oftalmología, asumiendo que la mucosa ocular puede ser una vía de entrada del virus y a la vez una fuente de contagio.También considerar la potenciación de la infección viral con las enfermedades de base asociadas, como glaucoma y diabetes.Se sugiere además incorporar estudios histológicos de la mucosa ocular para diferenciar epitelios sanos e infectados.

SUMMARY: SARS CoV-2, the causal agent of the Covid- 19 disease, infects the digestive and respiratory mucosa, affecting epithelial cells. The virus enters through the ACE2 membrane receptor causing the disruption of cell homeostasis. Frequent reports indicate the presence of ocular conjunctivitis in patients diagnosed with Covid-19, which has alerted scientists to the potential source of viral infection from lacrimal secretions. The epithelia of the sub-palpebral and corneal ocular conjunctiva are characterized by presenting the receptor for angiotensin-converting enzyme 2 (ACE2) and associated transmembrane protease serine 2 (TMPRSS2), whose interaction activates cytokine release mechanisms, with the ability to start the infectious conjunctivitis process by SARS CoV-2, but not necessarily extend the infection to the digestive and respiratory systems. Although this inflammatory process is more frequent as an expression of the general and more serious infection. However, whatever the route of infection or entry of the SARS CoV-2 virus, it is important to consider the risk of infection of tears and conjunctival secretions in patients. This study aims to draw attention to health care and control measures, incorporating better standards of personal protection and biosafety, especially in the areas of ophthalmology, assuming that the ocular mucosa can be a route of entry for the virus, and at the same time a source of contagion. A further consideration is the potential of viral infection with associated underlying diseases, such as glaucoma and diabetes. It is also suggested to incorporate histological studies of the ocular mucosa to differentiate healthy and infected epithelia.

Tratamento de crescimento epitelial persistente pós-Lasik com debridamento mecânico, uso de álcool a 20% e cola de fibrina / Treatment of persistent epithelial ingrowth after Lasik with mechanical debridement, use of 20% alcohol and fibrin glue

RESUMO O Lasik é a técnica de cirurgia refrativa mais utilizada no mundo. Apesar de segura e efetiva, ela pode levar a algumas complicações. O crescimento epitelial pós-Lasik é uma complicação pós-operatória incomum, com prevalência maior em casos de retratamento. Geralmente, é um achado não progressivo e assintomático, que não requer tratamento, mas, em uma minoria de pacientes, os sintomas podem ser clinicamente significantes e variados. O tratamento é feito com debridamento mecânico do crescimento epitelial, mas alguns recursos adjuvantes também podem ser utilizados. O presente estudo consiste em um relato de caso de paciente com crescimento epitelial pós-Lasik que apresentou quatro recidivas após intervenções de debridamento epitelial, sutura de lamela corneana e ablação a laser. No quinto procedimento, o paciente foi finalmente tratado com combinação de debridamento epitelial, uso de álcool a 20% e cola de fibrina. Entretanto, a regressão do crescimento epitelial e a melhora da acuidade visual só ocorreram ao longo dos meses após a intervenção, o que mostra a importância de esperar um tempo para que ocorra a melhora da visão no pós-operatório, evitando-se reintervenções.

ABSTRACT Lasik is the most often performed laser refractive surgery worldwide. Despite its efficacy and safety, some complications may occur. Epithelial ingrowth is a rare postoperative complication of Lasik, with an increased prevalence in cases of retreatment. Epithelial ingrowth is usually a nonprogressive and asymptomatic finding, which requires no treatment; however, in a minority of cases, symptoms may be clinically significant and diverse. Treatment is done with mechanical debridement of the affected interface, and additional interventions may be required. This study reported a case of recalcitrant epithelial ingrowth after Lasik, whichrelapsed four times after mechanical debridement, flap lift and laser ablation. In the fifth intervention, the patient was finally treated with a combined scraping/use of 20% alcohol and fibrin glue. However, regression of epithelial ingrowth and better visual acuity were only observed some months after the intervention, which shows the importance of waiting for better vision in the postoperative period, thus avoiding new reinterventions.

Effect of the bioprotectant agent trehalose on corneal epithelial healing after corneal cross-linking for keratoconus / Efeito do agente bioprotetor trealose na cicatrização epitelial da córnea após reticulação corneana para ceratocone

ABSTRACT Purpose: This study aimed to compare the effectiveness of eye drops containing a combination of sodium hyaluronate and trehalose and sodium hyaluronate for the treatment of corneal cross-linking and epithelial healing. Methods: This study included 46 eyes of 23 keratoconus patients who underwent corneal cross-linking on both eyes. Unpreserved trehalose 30 mg/mL and sodium hyaluronate 1.5 mg/mL (Thealoz Duo®; Thea, France) were applied six times a day on one eye of each patient and unpreserved sodium hyaluronate 0.15% (Eye Still®; Teka, Inc., Istanbul) was applied on the other eye. Patients were examined daily until complete re-epithelialization. Postoperative examinations to assess the measured size of epithelial defect were performed using slit-lamp biomicroscopy. Results: The study included 23 patients (13 females and 10 males) with a mean age of 20.9 ± 10.3 years. Corneal epithelial healing time after cross-linking was 2.3 ± 1.2 days for the trehalose and sodium hyaluronate group and 3.8 ± 2.9 days for the sodium hyaluronate group (p=0.03). Conclusion: The application of eye drops containing the combination of trehalose and sodium hyaluronate resulted in faster corneal re-epithelialization following corneal cross-linking than that of eye drops containing sodium hyaluronate alone.

RESUMO Objetivo: Este estudo teve como objetivo comparar a eficácia de colírios contendo uma combinação de hialurônico de sódio e hialuronato de sódio e trealose para o tratamento da cicatrização epitelial em pacientes com cross-linking corneano. Métodos: Este estudo inclui 46 olhos de 23 pacientes com ceratocone, que foram operados com cross-linking corneano em ambos os olhos. Trealose não preservada 30 mg/mL e hialuronato de sódio 1,5 mg/mL (Thealoz Duo®; Thea, França) foram aplicados seis vezes por dia em um olho de cada paciente e hialuronato de sódio não conservado, 0,15% (Eye Still®; Teka, Inc., Istambul) foi aplicada no outro olho. Os pacientes foram examinados diariamente até a completa reepitelização. Exames pós-operatórios para avaliar o tamanho medido do defeito epitelial foram realizados usando biomicroscopia com lâmpada de fenda. Resultados: O estudo incluiu 23 pacientes (13 mulheres e 10 homens) com idade média de 20,9 ± 10,3. O tempo de cicatrização epitelial da córnea após o cross-linking foi de 2,3 ± 1,2 dias para o grupo trealose e hialuronato de sódio e 3,8 ± 2,9 dias para o grupo hialurônico de sódio (p=0,03). Conclusão: A aplicação de gotas para os olhos contendo combinação de trealose e hialuronato de sódio resultou em uma re-epitelização da córnea mais rápida após o cross-linking corneano do que a de gotas contendo hialurônico de sódio apenas.

Clinical features and corneal optical anisotropies in a rabbit model of limbal stem cell deficiency / Fenótipos clínicos e anisotropias ópticas da córnea em coelhos com deficiência de células tronco limbais

ABSTRACT Purposes: To investigate the intra-laboratory reproducibility of clinical features and to evaluate corneal optical anisotropies in a rabbit model of limbal stem cell deficiency. Methods: Limbal injury was induced in the right eye of 23 adult New Zealand White rabbits using a highly aggressive protocol that combined 360 degrees limbal peritomy, keratolimbectomy, alkaline chemical burn, and mechanical removal of the epithelium. Clinical evaluation of the injured eyes was performed for 28 days and included corneal impression cytology. Corneas with a severe clinical outcome set typical of limbal stem cell deficiency were then collected, subjected to a histopathological examination, and examined for optical anisotropies. Corneas from healthy rabbit eyes were used as controls. Differences in optical path due to stromal collagen birefringence, as well as linear dichroism related to the expression and spatial orientation of glycosaminoglycan chains from proteoglycans, were measured from cross-sections under a quantitative polarized light microscope. Results: One eye showed signs of hypopyon and was excluded. Signs of ocular inflammation were observed in all eyes studied (n=22). Corneal impression cytology did not detect goblet cells. Twelve of the 22 corneas presented a clinical outcome set typical of limbal stem cell deficiency, which is characterized by the presence of epithelial defects, inflammatory cells, moderate-to-severe opacity, and neovascularization. Microscopic studies under polarized light revealed that relative to controls, limbal stem cell deficiency caused a 24.4% increase in corneal optical path differences. Further, corneas with limbal stem cell deficiency were less dichroic than controls. Conclusions: These results suggest that rabbit models of limbal stem cell deficiency must be rigorously screened for use in preclinical studies to ensure experimental homogeneity because protocols used to create limbal stem cell deficiency could be not associated with good intra-laboratory reproducibility of clinical features. Limbal stem cell deficiency, as induced herein, altered the optical anisotropic properties of the corneal stroma. Such alterations are indicative of changes in collagen packing and the spatial orientation of glycosaminoglycan chains from proteoglycans. Knowledge of these changes is important to potentiate strategies aimed at restoring the morphofunctional integrity of the corneal stroma affected by limbal stem cell deficiency.

RESUMO Objetivos: Investigar a reprodutibilidade intra-la­boratorial dos fenótipos clínicos e avaliar anisotropias ópticas em córneas de coelhos com deficiência de células tronco limbais. Métodos: Lesões ao limbo foram feitas no olho direito de 23 coelhos adultos da Nova Zelândia Branco, usando um protocolo altamente agressivo, que envolveu peritomia limbal em 360 graus, ceratolimbectomia, cauterização por álcali, e remoção mecânica de epitélio remanescente. Os olhos foram clinicamente avaliados por 28 dias, inclusive por citologia de impressão corneal. As córneas que manifestaram um conjunto de alterações típicas de deficiência de células tronco limbais foram coletadas e submetidas à estudos em histopatologia e em anisotropias ópticas. Córneas saudáveis foram usadas como controles. Diferenças de caminho óptico de birrefringência relacionada à organização do colágeno estromal, e dicroísmo linear relacionado à expressão e à orientação das cadeias de glicosaminoglicanos dos proteoglicanos estromais, foram quantificados por microscopia de luz polarizada. Resultados: Um olho apresentou hipópio e foi excluído do estudo. Todos os olhos estudados (n=22) apresentaram sinais de inflamação ocular. A citologia de impressão não detectou células caliciformes na superfície corneal. Doze de 22 córneas manifestaram alterações clínicas típicas de deficiência de células tronco limbais, caracterizado por defeitos epiteliais, infiltrados inflamatórios, opacidade de moderada à severa, e neovascularização. Estudos por microscopia de luz polarizada mostraram que a deficiência de células tronco limbais aumentou a diferenças de caminho óptico corneal em 24,4% (versus controles). As cór­neas com deficiência de células tronco limbais foram menos dicroicas do que as córneas controle. Conclusões: Coelhos com deficiência de células tronco limbais, para aplicações em estudos pré-clínicos, devem ser rigorosamente selecionados para assegurar homogeneidade experimental, pois há evidências de que protocolos utilizados para indução de deficiência de células tronco limbais não estão associados com boa reprodutibilidade intra-laboratorial de fenótipos clínicos. A deficiência de células tronco limbais, como induzida aqui, alterou as propriedades ópticas anisotrópicas do estroma corneal. Tais alterações são indicativas de mudanças no empacotamento de colágeno e na orientação das cadeias de glicosaminoglicanos dos proteoglicanos. Conhecimentos nessas alterações são importantes para potencializar estratégias que visam a restabelecer a integridade morfofuncional do estromal corneal acometido pela deficiência de células tronco limbais.

Brown-McLean Syndrome in a Patient with Hallermann-Streiff Syndrome

No abstract available.

Localized flap melt after Nd-YAG laser treatment in recurrent post-LASIK epithelial ingrowth / Derretimento localizado de flap após o tratamento por Nd-YAG laser para crescimento epitelial recorrente pós-LASIK

ABSTRACTNeodymium: Yttrium-Aluminum-Garnet (Nd-YAG) laser treatment of epithelial ingrowth was found promising with high success rates in cases of primary post-LASIK epithelial ingrowth. However, the application range of this procedure is not well-known. For the first time, the authors report the outcome of a patient treated with Nd-YAG laser for multiple recurrences of post-laser in situ keratomileusis epithelial ingrowth.

RESUMOO tratamento com laser de neodímio: Ítrio-Alumínio-Granada (do inglês, Nd-YAG Laser) para o crescimento epitelial primário pós-LASIK demonstrou altas taxas de sucesso. No entanto, os limites deste procedimento não são completamente conhecidos. Pela primeira vez, os autores relatam os resultados de um olho tratado com Nd-YAG laser para múltiplo crescimento epitelial pós-LASIK recorrente que desenvolveu um derretimento localizado do flap.

Presentation, diagnosis and management of limbal stem cell deficiency

The human corneal surface epithelium is continuously repopulated by the limbal stem cells [LSCs]. Limbal Stem Cell Deficiency [LSCD] can lead to corneal opacity and vascularization, with consequent visual impairment or blindness. Many acquired and congenital diseases can lead to LCSD by direct injury to the LSCs, destruction of LSC niche, or both. Based on the severity of the disease, LSCD can present with various symptoms and signs. Although LSCD can be detected clinically, laboratory tests are necessary to confirm the diagnosis and monitor the disease progression. This article concisely reviews the clinical presentation, techniques for diagnosis and management of LSCD

Cytokeratin expression in corneal dystrophies / Expressão de citoqueratinas em distrofias corneanas

PURPOSE: To identify an immunohistochemical pattern of epithelial markers in granular, lattice and Avellino corneal dystrophies. METHODS: Twenty-two corneal buttons, diagnosed as lattice (17), Avellino (4) and granular (1) underwent immunohistochemical studies of cytokeratins (CKs) on pa- raffin-embedded sections (group I). Monoclonal antibodies for pan-CK (AE1/AE3) and CKs 3/12, 5/6, 8, 18 and 19 were used. Twenty-two normal corneas were used as the control (group II). RESULTS: Six lattice and 2 Avellino cases of group I stained positively with anti-CK 3/12 in corneal epithelium and areas of corneal stroma deposits. One of these cases of lattice was positive for anti-pan-CK (AE1/AE3) also in the epithelium and areas of corneal stroma deposits with a similar pattern. None of the controls (group II) revealed any staining in corneal stroma. All disease and control cases (groups I and II) revealed positive staining in corneal epithelium. CONCLUSION: AE1/AE3 and CK 3/12 anti-CK positive markers in the stromal deposits of lattice and Avellino dystrophies may suggest an epithelial genesis of the disease.

OBJETIVO: Investigar a expressão de citoqueratinas (CKs) em córneas com distrofias corneanas tipo granular, lattice e Avellino. MÉTODOS: Vinte e dois botões corneanos com diagnóstico anatomopatológico de distrofia estromal tipo lattice (17), Avellino (4) e granular (1) foram submetidos à avaliação imunohistoquímica nos tecidos inclusos em parafina (grupo I). Anticorpos monoclonais para pan-CK (AE1/AE3) e CKs de números 3/12, 5/6, 8, 18 e 19 foram utilizados. Vinte e dois botões corneanos normais foram usados como controle (grupo II). RESULTADOS: Oito casos do grupo I (seis lattice e dois Avellino) apresentaram reações imuno-histoquímicas positivas com anti-CK 3/12, tanto no epitélio como nos depósitos estromais e um destes casos (lattice) também se mostrou positivo para anti-pan-CK (AE1/AE3) com o mesmo padrão de reação. Nenhum caso do grupo II mostrou reação imuno-histoquímica positiva no estroma corneano. Na avaliação imuno-histoquímica dos grupos I e II, o epitélio apresentou uma reação positiva com o anticorpo anti-pan-CK (AE1/AE3) e com o anti-CK 3/12. CONCLUSÃO: O fato da pan-CK e CK 3/12 apresentarem uma reação positiva nos depósitos das distrofias tipo lattice e Avellino sugere uma origem epitelial desses depósitos corneanos.

Histological and immunohistochemical study of the effect of travoprost with and without benzalkonium chloride on the corneae epithelium of adult male albino rat

Chronic topical glaucoma therapy has been reported to cause deleterious changes to the ocular surface layers. Benzalkonium chloride [BAK] is the most commonly used ocular preservative, especially in antiglaucoma drugs. It is largely responsible for the ocular toxicities and inflammation associated with the chronic use of many ophthalmic solutions. This work aimed to compare structural changes in corneae epithelium of rats after chronic exposure to travoprost 0.004% eye drops preserved without BAK, travoprost 0.004% eye drops preserved with BAK and BAK alone. Forty adult male albino rats were divided into five equal groups and created topically once daily for eight weeks; group I [control group], group II received sofzia preservative system, group III received travoprost 0.004% eye drops preserved with sofzia [Travatan Z], group IV received BAK 0.015% and group V received travoprost 0.004% eye drops preserved with 0.015% BAK [Travatan]. At the end of the experiment, cortical specimens were processed for histological study by light and electron microscopes as well as immunohistochemical study with monoclonal antibody to cytokeratin-3 [CK-3]. Corneal epithelium of animals treated with BAK alone and those treated with travoprost preserved with BAK showed desquamation of epithelial cells, significant decrease of epithelial thickness, focal disruption of Bowman's membrane, loss of microvilli, cytoplasmic-vacuolation, nuclear fragmentation and swollen mitochondria with widening of intercellular spaces. lmmunohistochemical study revealed significant decrease in the expression of CK-3 in the cytoplasm of epithelial cells. However, no obious histological changes were recorded in corneal specimens in animals treated with travoptost preserved with sofzia with normal expression of CK-3 in the cytoplasm of epithelial cells. Once-daily dosing of travoprost preserved with BAR produced significant corneal epithelial changes. However, the use of glaucoma medications with alternative preservatives as sofzia can preserve corneal health

HLA-matched living-related conjunctival limbal allograft for bilateral ocular surface disorders: long-term results / Transplante alogênico inter vivo de limbo conjuntival com pareamento HLA em doenças bilaterais da superfície ocular: resultados em longo prazo

PURPOSE: To evaluate the long-term outcome of HLA-matched lr-CLAL for bilateral ocular surface disorders. METHODS: A retrospective, non-comparative interventional case series study of 39 eyes of 32 patients with bilateral surface disorders and clinical diagnosis of limbal stem cell deficiency who underwent HLA-matched lr-CLAL. Visual acuity (VA), ambulatory vision (> 20/200) and ocular surface stability were evaluated as main outcomes. Donor limbus was obtained from a sibling or a parent of the patient, after an appropriate Class I and II HLA match. RESULTS: One year after surgery, VA improved in 46.2 percent, ambulatory vision was achieved in 48.7 percent and a stable corneal surface was achieved in 84.6 percent of the eyes. At the final follow-up (mean, 48.7 ± 30.6 months), 66.6 percent of the eyes that had gained VA one year after surgery maintained an improved VA (p=0.28), 94.7 percent of eyes that had achieved ambulatory vision one year after surgery maintained 20/200 or better (p<0.001) and 93.9 percent still had a stable corneal surface (p=0.043) at the final follow-up. CONCLUSIONS: HLA-matched lr-CLAL can be an adequate method of treatment for bilateral ocular surface disorders, with a reasonable percentage of success of long-term results.

OBJETIVO: Avaliar os resultados em longo prazo do transplante alogênico inter vivo de limbo conjuntival para doenças bilaterais da superfície ocular com compatibilidade HLA doador-receptor. MÉTODOS: Estudo retrospectivo, não comparativo e intervencionista de 39 olhos de 32 pacientes submetidos a transplante alogênico de limbo com compatibilidade HLA e diagnóstico de deficiência límbica. Foram analisados como desfechos principais acuidade visual, visão ambulatorial (> 20/200) e estabilidade da superfície ocular. Limbo doador foi obtido de parentes do paciente após estudo de compatibilidade HLA classe I e II. RESULTADOS: Com um ano de pós-operatório, a acuidade visual melhorou em 46,2 por cento, visão ambulatorial foi atingida em 48,7 por cento e estabilidade da superfície corneana em 84,6 por cento dos pacientes. Ao final do seguimento (média, 48,7 ± 30,6 meses), 66,6 por cento dos olhos que haviam ganho acuidade visual um ano após a cirurgia mantiveram esta melhora (p=0,28), 94,7 por cento dos olhos que haviam alcançado visão ambulatorial um ano após a cirurgia mantiveram visão de 20/200 ou melhor (p<0,001) e 93,9 por cento ainda tinham superfície corneana estável (p=0,043) ao final do seguimento. CONCLUSÕES: O transplante alogênico inter vivo de limbo conjuntival com compatibilidade HLA revelou-se método adequado no tratamento de doenças bilaterais da superfície ocular, com uma porcentagem significativa de sucesso a longo-prazo.

Citologia de impressão no diagnóstico de infecção corneana por Acanthamoeba: relato de caso / Diagnosis of Acanthamoeba corneal infection by impression cytology: case report

Relatamos três casos de infecção corneana por Acanthamoeba sp em que foi possível detectar cistos do microorganismo com a técnica de citologia de impressão. Três pacientes encaminhados ao Laboratório de Doenças Externas Oculares em 2004 com alterações superficiais da córnea foram submetidos ao exame de citologia de impressão para investigação da presença de cistos de Acanthamoeba sp. Duas amostras foram obtidas da córnea de cada paciente e coradas com PAS, hematoxilina e Papanicolaou. Investigação microbiológica de rotina e cultura também foram realizadas após raspado da córnea. O cultivo das amostras e a citologia de impressão foram positivas para Acanthamoeba sp em todos os pacientes, ao passo que os raspados corados com Giemsa foram positivos em dois casos. A citologia de impressão revelou cistos de Acanthamoeba sp entre feixe de células epiteliais corneanas e como células isoladas. Foram observados cistos no epitélio de um dos pacientes com a citologia de impressão após três meses de tratamento, enquanto o raspado foi negativo. No exame anatomopatológico observaram-se cistos no epitélio e estroma de uma córnea receptora de um dos pacientes após transplante. Neste estudo, a citologia de impressão detectou com sucesso cistos de Acanthamoeba sp em pacientes com acometimento epitelial. Por tratar-se de método não invasivo, a técnica pode ser usada para facilitar o diagnóstico mais precoce da infecção por Acanthamoeba, sendo útil também no acompanhamento do tratamento da doença.

To describe three cases of corneal infection due to Acanthamoeba sp in which was possible to detect Acanthamoeba sp cysts by the corneal impression cytology technique. Three patients referred to the External Eye Disease Laboratory in 2004 with superficial corneal alterations were submitted to corneal specimen collection by impression cytology filter paper to investigate the presence of Acanthamoeba sp cysts. Two impression cytology samples were obtained from each patient and were stained by PAS, hematoxylin and Papanicolaou. Routine microbiological investigation and culture were also performed using corneal scraping. Positive culture and impression cytology for Acanthamoeba sp was observed in all patients while smears with Giemsa stain were positive in two. Impression cytology Acanthamoeba sp cysts were observed among sheets of corneal epithelial cells and as isolated cells. Cysts were also found in the superficial epithelium in one of these patients after treatment while corneal scraping did not reveal any cyst. Histopathology revealed cysts in the epithelium and stroma in a transplanted cornea in one of these patients. The first description of impression cytology as a diagnostic method for Acanthamoeba keratitis occurred recently. In this study corneal impression cytology detected Acanthamoeba sp cysts successfully in these patients with only superficial involvement. Impression cytology as a non invasive technique can be used to facilitate early recognition of Acanthamoeba infection playing a useful role in the follow-up of the disease.

Effect of Base Curve Radius of Therapeutic Lenses on Epithelial Healing after Laser-Assisted Subepithelial Keratectomy

PURPOSE: To determine the effect of the base curve radius (BCR) of therapeutic soft contact lens (T-lens) on epithelial healing after laser-assisted subepithelial keratectomy (LASEK). METHODS: Ninety-two eyes in 47 patients with myopia were prospectively evaluated after LASEK. All the patients wore T-lenses with the BCR (R1) randomly chosen after LASEK. The T-lenses were removed after complete healing of the epithelial wounds. We calculated an estimated BCR (R2) from postoperative topography using a diopter conversion table. The patients were divided into two groups according to the differences between the BCR (R1) and the estimated BCR (R2). The flat fitting group was R1 > R2 (Group A), and the steep fitting group was R1R2) had 53 eyes, and Group B (R1

Effect of Base Curve Radius of Therapeutic Lenses on Epithelial Healing after Laser-Assisted Subepithelial Keratectomy

PURPOSE: To determine the effect of the base curve radius (BCR) of therapeutic soft contact lens (T-lens) on epithelial healing after laser-assisted subepithelial keratectomy (LASEK). METHODS: Ninety-two eyes in 47 patients with myopia were prospectively evaluated after LASEK. All the patients wore T-lenses with the BCR (R1) randomly chosen after LASEK. The T-lenses were removed after complete healing of the epithelial wounds. We calculated an estimated BCR (R2) from postoperative topography using a diopter conversion table. The patients were divided into two groups according to the differences between the BCR (R1) and the estimated BCR (R2). The flat fitting group was R1 > R2 (Group A), and the steep fitting group was R1R2) had 53 eyes, and Group B (R1

A Novel Application of Amniotic Membrane in Patients with Bullous Keratopathy

To evaluate the efficacy of amniotic membrane in the management of painful bullous keratopathy secondary to the intractable glaucoma and in preventing exposure of drainage devices, we inserted Ahmed valve with amniotic membrane patch graft over the implant itself, and debrided corneal epithelium with amniotic membrane graft over the exposed stroma as a single operation. During the follow-up periods, we monitored vision, intraocular pressure (IOP), presence of ocular pain, and postoperative complications associated with the implants. The mean follow up period was 8.4+/-3.2 months. IOP was well controlled after the intervention. The preoperative mean IOP was measured as 43.9+/-9.0 mmHg and lowered to 16.1+/-1.8 mmHg at the last visit and no complications associated with the implants were noted. Even though the improvement in vision was not prominent, the ocular surface stabilized rapidly and ocular pain associated with bullous keratopathy disappeared soon after surgery. Conclusively the use of amniotic membrane in conjunction with Ahmed valve implantation is an effective way to relieve ocular pain and lessen the chances of complications associated with the implant in patients with intractable glaucoma and bullous keratopathy.

Queratotoxon o anillos cornéales / Corneal rings

Los anillos cornéales habitualmente no son completos, pueden representar desde cambios fisiológicos (anillo limbar ) hasta enfermedades que, si no son diagnosticadas y tratadas oportunamente, pueden terminar con la visión, el ojo e, incluso, con la vida del paciente (anillo limbar, embriotoxon anterior, embriotoxon posterior), de la segunda a cuarta década de la vida (arco juvenil, anillo de Fleisher, anillo de Kayser-Fleisher, queratoconjutivitis alérgica, distrofia corneal anular, desgeneración marginal de Terrien) y seniles (gerotoxon). La distrofia corneal de Schnyder puede presentarse tan precozmente como al año y medio de edad. El anillo por anestésico local, lo hemos visto desde la adolescencia en adelante. Los anillos cornéales intraestromales se implantan, en general, a partir de la tercera o cuarta década de la vida. El anillo de Wessely, el anillo por queratoplastía y el anillo blanco de Cotas pueden presentarse en cualquier etapa de la vida. Respecto a su ubicación pueden ser paracentrales, paralimbares y perilesionales.

Bilateral epithelial defects after laser in situ keratomileusis. Clinical features, management and outcome.

PURPOSE: To describe the preoperative characteristics, intraoperative details, management, and postoperative in patients with bilateral epithelial defects after laser in situ keratomileusis (LASIK). METHODS: Retrospective non-comparative case series. RESULTS: Six patients with bilateral epithelial defects after LASIK were part of a cohort of 605 patients undergoing bilateral LASIK at our center from December 2001 to April 2003. The mean age of the patients (5M:1F) was 28.5 +/- 7.9 years, and the average pretreatment myopic spherical equivalent (SE) refraction was 7.3 +/- 0.7 D (-4, -12.25D). An epithelial flap was present in 6 eyes and an epithelial defect with a mean diameter of 3 mm (2mm, 6mm) was seen in 6 eyes. In four patients the epithelial disturbance was bilaterally similar. All defects occurred in the inferior cornea and the epithelial flaps had the hinge positioned superiorly. None of the patients had ocular or systemic risk factors that could have resulted in this complication. A bandage contact lens was used in 6 eyes. At last follow-up of 5.5 +/- 9.5 months (0.25, 21 months), unaided visual acuity was 6/9 or better in 10 eyes. Best spectacle-corrected visual acuity (BSCVA) was maintained in 8 eyes, while 4 eyes lost one line of BSCVA. Recurrent corneal erosions were not reported in the follow-up period. CONCLUSIONS: These patients represent a hitherto unrecognised group of individuals who appear to have a subclinical weakness of adhesion of the corneal epithelium to the underlying structures, which is not evident on clinical examination. This results in bilateral epithelial disturbances after LASIK. Appropriate management results in satisfactory clinical outcomes. Other options for treatment of the fellow eye of such patients include the use of a different microkeratome, release of suction during the reverse pass of the Hansatome microkeratome, and photorefractive keratectomy if the refractive error is low.

Impression Cytology of Herpetic Simplex Keratitis in Rabbits

PURPOSE: To use impression cytology to examine the structural changes in corneal epithelial cells infected with the herpes simplex virus in rabbit eyes. METHODS: Corneal surfaces of 7 rabbits were scratched using a 25-gauge needle. Herpes simplex virus (type 1, Kos strain) was inoculated to the injured cornea. As the corneal diseases were observed using slit lamp biomicroscopy, impression cytology was performed for 18 days after inoculation. Specimens were stained with hematoxylin-eosin and examined using optical microscopy. RESULTS: Corneal lesions consisted mainly of round epithelial cells, inflammatory cells, ballooning cells, multinucleated giant cells, and various inclusion bodies. Over time, the corneal epithelial cells peeled away as a result of corneal edema in the corneal lesions. Dendritic lesions were also observed. In the recovery phase, the number of detached cells and infiltrated inflammatory cells decreased. CONCLUSIONS: It was presumed that dendritic lesions might have been formed at the scratched cornea region, thereby aggravating the epithelial cells falling off as a result of the infiltration of inflammatory cells. These cytopathologic effects occur in experimental herpes simplex keratitis.

Uso de mitomicina C tópico no tratamento da neoplasia intra-epitelial córneo-conjuntival e carcinoma espinocelular conjuntival: resultados preliminares / Topical use of mitomycin C for the treatment of corneal-conjunctival intraepithelial neoplasia and conjunctival squamous cell carcinoma: preliminary results

OBJETIVO: Avaliar a segurança, a eficácia e a recidiva tumoral após o uso de mitomicina C (MMC) tópica no tratamento de neoplasias intra-epiteliais (NIC) primárias e recidivadas e carcinomas espinocelulares (CEC) recidivados. MÉTODOS: Dois grupos de pacientes foram tratados. Grupo 1 com diagnóstico de NIC primário ou recidivado fez uso do colírio de MMC 0,02 por cento, 4 vezes ao dia por 28 dias. O grupo 2 com diagnóstico de CEC recidivado fez uso do colírio de MMC 0,02 por cento, 4 vezes ao dia por 21 a 28 dias. Após o término do tratamento era feita citologia exfoliativa para controle ou biópsia nos casos de lesão residual. RESULTADOS: Oito pacientes com NIC e 1 com CEC mostraram regressão total da lesão e citologia exfoliativa de controle negativa para células neoplásicas. Em 1 paciente com NIC e 2 com CEC, houve regressão parcial das lesões, tendo sido necessária exérese cirúrgica da lesão residual, com exame anatomopatológico negativo para neoplasia. Os efeitos colaterais foram transitórios e desapareceram após a suspensão do colírio. Não houve recidiva tumoral num seguimento médio de 24,9 meses. CONCLUSÃO: Os resultados preliminares desse estudo su-gerem que o uso da MMC tópica é opção segura e eficaz como tratamento único de NIC primária ou recidivada e no tratamento do CEC recidivado, porém não evitando a cirurgia na maioria dos pacientes com CEC. Não foram observadas recidivas tumorais durante o segmento. Mais estudos são necessários, com maior número de pacientes e maior tempo de seguimento para confirmar esses resultados.

Microscopia confocal in vivo na epitelização da interface após lasik / In vivo confocal microscopy of corneal epithelial ingrowth after lasik

Objetivo: Descrever os achados da microscopia confocal in vivo em um caso no qual LASIK para correção de astigmatismo miópico composto foi realizado em ambos olhos e que, no pós-operatório precoce, o paciente desenvolveu epitelização da interface no olho esquerdo. Local: Eye Clinic Day Hospital. Métodos: Estudo descritivo, onde se relata e discute a epitelização da interface após LASIK e os achados da Microscopia Confocal in vivo nesta complicação. Resultados: Após realizar LASIK o paciente apresentou, no primeiro pós-operatório (PO), AVSC 20/40 OD e 20/25 OE, retornando no terceiro PO com AVSC de 20/25p OD e 20/150 OE, sendo observado epitelização da interface em OE à biomicrospia. A microscopia confocal in vivo (MC) no OE revelou: epitélio, flap e interface normal à MC, e epitelização da interface, ao examinarmos o achado biomicroscópico. Após a retirada do epitélio o paciente apresentou AVSC 20/20 AO. Conclusão: Este relato de caso descreve, pela primeira vez no Brasil, os achados da microscopia confocal in vivo na epitelização da interface após LASIK. Apesar de ser uma complicação em que geralmente há um desconforto visual e diminuição (quantitativa e/ou qualitativa) da AVSC, a epitelização da interface pode ser resolvida com relativa facilidade.