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OBJECTIVES: To examine clinical outcomes of oversized titanium back plates in type I Boston keratoprosthesis (KPro) implantation. METHODS: Retrospective study of 22 sequential eyes (20 patients) undergoing type I KPro implantation with an oversized titanium back plate (larger than trephined wound diameter by 1.0 mm or more), performed by a single surgeon (K.A.C.) from June 2010 to November 2014. Data were collected regarding preoperative eye characteristics, surgical details, and postoperative clinical outcomes. RESULTS: Mean follow-up time per eye was 24.1±14.9 months. All eyes had improved vision after surgery; 13 eyes (59.1%) maintained visual acuity improvement at last follow-up. Initial KPro's were retained in 19 eyes (86.4%); one eye required KPro replacement. Primary retroprosthetic membrane (RPM) developed in three eyes (13.6%), with similar occurrence in aniridic (14.3%) and nonaniridic eyes (13.3%). Secondary RPM's developed in two eyes (9.1%) after vitritis (one eye) and retinal and choroidal detachment (one eye). Glaucoma was a common comorbidity: 2 of 14 eyes (14.3%) with preoperative glaucoma had glaucoma progression, and 4 of 8 eyes (50.0%) without preoperative glaucoma developed glaucoma postoperatively. Other postoperative complications included retinal detachment (5 eyes, 22.7%) and idiopathic vitritis (3 eyes, 13.6%). CONCLUSIONS: Oversized titanium KPro back plates are associated with a low rate of primary RPM formation and may have particular utility in reducing primary RPM formation in aniridic eyes. Glaucoma remains a challenge in postoperative KPro management. Complex eyes, at increased risk of postoperative complications, require careful management.
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Órganos Artificiales , Enfermedades de la Córnea/cirugía , Prótesis e Implantes , Implantación de Prótesis/métodos , Adulto , Anciano , Córnea/cirugía , Femenino , Estudios de Seguimiento , Glaucoma/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Agudeza Visual , Adulto JovenRESUMEN
An unprecedented pigmented caruncular apocrine hidrocystoma with the additional feature of an oncocytic transformation of the cyst's lining cells is reported. Over a year, a 79-year-old woman developed a centrally pigmented lesion of her right caruncle with translucent borders. Because of concern about a melanoma, a carunculectomy with adjunctive cryotherapy and placement of an amniotic membrane graft were performed, and the excised specimen was evaluated microscopically. A large cyst dominated the caruncle and was lined by an inner layer of columnar eosinophilic and granular cells with an outer, interrupted layer of flattened myoepithelial cells. Phosphotungstic acid hematoxylin staining disclosed myriad cytoplasmic, dot-like mitochondria signifying an oncocytic change. Immunohistochemistry revealed gross cystic fluid disease protein-15 and cytokeratin 7-positivity indicative of apocrine differentiation. Oncocytic change is characteristically encountered in lacrimal ductal cysts and tumors.
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Glándulas Apocrinas/patología , Quistes/diagnóstico , Neoplasias del Ojo/diagnóstico , Hidrocistoma/diagnóstico , Aparato Lagrimal/patología , Neoplasias de las Glándulas Sudoríparas/diagnóstico , Anciano , Diagnóstico Diferencial , Femenino , HumanosRESUMEN
Purpose: We sought to introduce the materials, design, and biocompatibility of a flexible and suturable artificial corneal device. Methods: Single-piece, fully synthetic, optic-skirt design devices were made from compact perfluoroalkoxy alkane. The skirt and the optic wall surfaces were lined with a porous tissue ingrowth material using expanded polytetrafluoroethylene. Full-thickness macroapertures around the skirt perimeter were placed to facilitate nutrition of the recipient cornea. Material properties including the skirt's modulus of elasticity and bending stiffness, optic light transmission, wetting behavior, topical drug penetrance, and degradation profile were evaluated. Results: The final prototype suitable for human use has a transparent optic with a diameter of 4.60 mm anteriorly, 4.28 mm posteriorly, and a skirt outer diameter of 6.8 mm. The biomechanical and optical properties of the device closely align with the native human cornea with an average normalized device skirt-bending stiffness of 4.7 kPa·mm4 and light transmission in the visible spectrum ranging between 92% and 96%. No optical damage was seen in the 36 devices tested in fouling experiments. No significant difference was observed in topical drug penetrance into the anterior chamber of the device implanted eye compared with the naïve rabbit eye. Conclusions: The flexibility and biocompatibility of our artificial cornea device may offer enhanced tissue integration and decreased inflammation, leading to improved retention compared with rigid keratoprosthesis designs. Translational Relevance: We have developed a fully synthetic, flexible, suturable, optic-skirt design prototype artificial cornea that is ready to be tested in early human feasibility studies.
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Materiales Biocompatibles , Córnea , Ensayo de Materiales , Diseño de Prótesis , Animales , Conejos , Materiales Biocompatibles/química , Ensayo de Materiales/métodos , HumanosRESUMEN
PURPOSE: The aim of this study was to describe variations in practice patterns for the management of zone 1 open globe injuries among corneal specialists worldwide. METHODS: This cross-sectional study was performed using an online survey distributed to members of The Cornea Society. Responses were collected between September 9, 2021, and September 30, 2021. RESULTS: Of 94 responses included in analysis, respondents averaged 18.2 ± 14.5 years of postfellowship experience. Among respondents, 53 (56.4%) were affiliated with an academic institution and 41 (43.6%) with private practice. Ophthalmologists practicing in the United States were significantly more likely to use an eye shield preoperatively (98.5% vs. 85.7%, P = 0.03) and less likely to perform primary lensectomy in cases of lens involvement (40.9% vs. 75.0%, P = 0.002) compared with those practicing outside the United States. Ophthalmologists in practice fewer than 10 years were more likely to administer preoperative systemic antibiotics (91.4% vs. 66.1%, P = 0.006) and tetanus prophylaxis (88.6% vs. 67.8%, P = 0.03), and to obtain preoperative computed tomography scans (85.7% vs. 54.2%, P = 0.002) compared with more senior physicians. Ophthalmologists at academic institutions were more likely to perform preoperative B-scan (30.2% vs. 9.8%, P = 0.02), use general anesthesia (90.6% vs. 70.7%, P = 0.03), and admit for postoperative antibiotics (28.3% vs. 9.8%, P = 0.04), and were less likely to perform surgery overnight (45.3% vs. 70.7%, P = 0.02) compared with private practice physicians. CONCLUSIONS: There is significant variation in the practice patterns for the management of zone 1 open globe injuries among corneal specialists, which presents an opportunity to investigate whether certain treatment options lead to better outcomes in these injuries.
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Purpose: To report the biological stability and postoperative outcomes of a second-generation, single-piece, flexible synthetic cornea in a rabbit model. Methods: Device materials and design were amended to enhance biointegration. Optic skirt design devices were made from compact perfluoroalkoxy alkane with porous expanded polytetrafluoroethylene ingrowth surface overlying the skirt and optic wall. Sixteen devices were implanted into intrastromal pocket in rabbit eyes. Rabbits were randomly assigned to 6- and 12-month follow-up cohorts (n = 8 in each) postoperatively. Monthly examinations and optical coherence tomography assessed cornea-device integration, iridocorneal angle, optic nerve, and retina. Results: There were no intraoperative complications. All devices were in situ at exit, with clear optics. No retroprosthetic membrane, glaucoma, cataract formation, or retinal detachment was observed. Two rabbits in the 6-month group had mild, focal anterior lamella thinning without retraction adjacent to the optic near tight sutures. Three postoperative complications occurred in the 12-month group. One rabbit diagnosed with endophthalmitis was euthanized on day 228. Mild sterile focal retraction of anterior lamella occurred in two rabbits, which were terminated on days 225 and 315. Light microscopic examination of enucleated globes demonstrated fibroplasia with new collagen deposition into the porous scaffold without significant inflammation, encapsulation, or granuloma formation. Conclusions: Clinical evaluations, imaging, and histopathological findings indicate favorable outcomes of this synthetic corneal device in a rabbit model. Early feasibility studies in humans are being planned. Translational Relevance: Favorable 12-month results of the device in rabbits demonstrate vision-restoring potential in corneally blind individuals at high risk of failure with donor keratoplasty.
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Córnea , Prótesis e Implantes , Animales , Conejos , Colágeno , Córnea/cirugía , Prótesis e Implantes/efectos adversos , Retina/diagnóstico por imagen , Retina/cirugíaRESUMEN
PURPOSE: To describe the clinical characteristics, treatment, and outcomes of herpes simplex virus (HSV) infections of the cornea and adnexae to raise awareness and to improve management of this important eye disease in children. DESIGN: Retrospective case series. PARTICIPANTS: Fifty-three patients (57 eyes) 16 years of age or younger with HSV keratitis (HSK), HSV blepharoconjunctivitis (HBC), or both in an academic cornea practice. METHODS: The following data were collected: age at disease onset, putative trigger factors, coexisting systemic diseases, duration of symptoms and diagnoses given before presentation, visual acuity, slit-lamp examination findings, corneal sensation, dose and duration of medications used, drug side effects, and disease recurrence. MAIN OUTCOME MEASURES: Presence of residual corneal scarring, visual acuity at the last visit, changes in corneal sensation, recurrence rate, and manifestations of HSK were assessed in patients receiving long-term prophylactic systemic acyclovir. RESULTS: The median age at onset was 5 years. Mean follow-up was 3.6 years. Eighteen eyes had HBC only; 4 patients in this group had bilateral disease. Of 39 eyes with keratitis, 74% had stromal disease. Thirty percent of HSK cases were misdiagnosed before presentation. Seventy-nine percent of patients with keratitis had corneal scarring and 26% had vision of 20/40 or worse at the last visit. Eighty percent of patients had recurrent disease. Six of 16 patients (37%) receiving long-term oral acyclovir had recurrent HSV, at least one case of which followed a growth spurt that caused the baseline dosage of acyclovir to become subtherapeutic. CONCLUSIONS: In a large series, pediatric HSK had a high rate of misdiagnosis, stromal involvement, recurrence, and vision loss. Oral acyclovir is effective, but the dosage must be adjusted as the child grows.
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Segmento Anterior del Ojo/patología , Infecciones Virales del Ojo/diagnóstico , Infecciones Virales del Ojo/tratamiento farmacológico , Herpes Simple/diagnóstico , Herpes Simple/tratamiento farmacológico , Herpesvirus Humano 1/patogenicidad , 2-Aminopurina/administración & dosificación , 2-Aminopurina/análogos & derivados , Aciclovir/administración & dosificación , Aciclovir/análogos & derivados , Administración Tópica , Adolescente , Edad de Inicio , Segmento Anterior del Ojo/efectos de los fármacos , Segmento Anterior del Ojo/virología , Antivirales/administración & dosificación , Blefaritis/diagnóstico , Blefaritis/tratamiento farmacológico , Niño , Preescolar , Conjuntivitis Viral/diagnóstico , Conjuntivitis Viral/tratamiento farmacológico , Conjuntivitis Viral/virología , Infecciones Virales del Ojo/virología , Famciclovir , Femenino , Herpes Simple/virología , Humanos , Lactante , Queratitis Herpética/diagnóstico , Queratitis Herpética/tratamiento farmacológico , Queratitis Herpética/virología , Masculino , Pomadas , Estudios Retrospectivos , Trifluridina , Valaciclovir , Valina/administración & dosificación , Valina/análogos & derivados , Vidarabina/administración & dosificaciónRESUMEN
PURPOSE: The purpose of this study was to describe the rationale and design of the Zoster Eye Disease Study (ZEDS). METHODS: ZEDS is a National Eye Institute-supported randomized clinical trial designed to determine whether 1 year of suppressive valacyclovir in patients with herpes zoster ophthalmicus (HZO) reduces complications because there is currently no high-quality evidence to support its use. Eligible patients are 18 years and older, immunocompetent, have a history of a typical rash at disease onset, and have had a record of active epithelial or stromal keratitis or iritis within 1 year before enrollment. Exclusion criteria include estimated glomerular filtration rate less than 45 or pregnancy. The primary endpoint is the time to first occurrence of new or worsening dendriform epithelial keratitis, stromal keratitis without or with ulceration, endothelial keratitis, or iritis due to HZO during 12 months of study treatment requiring prespecified treatment changes. The study has 80% power to detect a 30% difference between treatment groups, with a 30% rate of endpoints by 1 year assumed among controls. Secondary and exploratory questions include whether there is a persistent treatment benefit during the 6 months after treatment, whether development of postherpetic neuralgia varies by treatment group, and whether vaccinations against herpes zoster affect study outcomes and coronavirus disease 19 status. RESULTS: Over approximately 4 years, over 400 study participants have been enrolled. CONCLUSIONS: ZEDS aims to provide scientific evidence on whether suppressive valacyclovir treatment improves outcomes in HZO and should become the standard of care.
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COVID-19 , Herpes Zóster Oftálmico , Herpes Zóster , Neuralgia Posherpética , Antivirales/uso terapéutico , Herpes Zóster Oftálmico/complicaciones , Herpes Zóster Oftálmico/diagnóstico , Herpes Zóster Oftálmico/tratamiento farmacológico , Humanos , Neuralgia Posherpética/diagnóstico , Neuralgia Posherpética/tratamiento farmacológico , Neuralgia Posherpética/epidemiología , Valaciclovir/uso terapéuticoAsunto(s)
Córnea , Oftalmología , Humanos , Complicaciones Posoperatorias , Prótesis e Implantes , Estados UnidosRESUMEN
PURPOSE OF REVIEW: To review emerging indications for the Boston keratoprosthesis (KPro) and to discuss current research underway to improve clinical outcomes. RECENT FINDINGS: In addition to multiple failed corneal grafts, other ocular conditions for which the Boston KPro has been used include herpetic keratitis, aniridia, autoimmune ocular disorders, and pediatric corneal opacities. In the recent years, the KPro has been implanted for various other conditions and has also been explored as a cost-effective treatment for severe corneal diseases internationally. Cicatricial and inflammatory ocular conditions remain the most difficult cases for KPro use but studies investigating various immunomodulators and biologic materials for improved retention are ongoing. Postoperative management of glaucoma is critical for preserving the visual gains achieved with the Boston KPro. Current studies are evaluating novel devices for intraocular pressure measurement. SUMMARY: Accrued experience with the Boston KPro has demonstrated its versatility but also the difficulties that remain in postoperative management. With many studies underway to improve cost-effectiveness, intra-operative and postoperative management, keratoprostheses will be made increasingly available to those countries most in need.
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Órganos Artificiales , Córnea , Enfermedades de la Córnea/diagnóstico , Enfermedades de la Córnea/cirugía , Prótesis e Implantes , Trasplante de Córnea , Humanos , Resultado del TratamientoRESUMEN
In this paper, we continue our evaluation of Forster-type theories of exciton diffusion in disordered environments. The perylenediimide dye Lumogen Red is used as a donor molecule in two different liquids, CHCl(3) and dimethylformamide, and the energy transfer to the acceptor molecule Rhodamine 700 is measured using time-resolved fluorescence decays. The exciton motion is measured over Lumogen Red concentrations ranging from 1 × 10(-4) to 5 × 10(-2) M, and the results are compared to previous results for exciton diffusion in a solid polymer. Depending on the theoretical approach used to analyze the data, we find that the energy migration in the liquids is a factor of 2-3 faster than in the solid polymer, even after taking molecular translation into account. Measurements for a Lumogen Red concentration of 10 mM in the different host environments yield diffusion constants ranging from 2.2 to 3.1 nm(2)/ns in the liquids, as compared to 1.1-1.2 nm(2)/ns in solid poly(methyl methacrylate) (PMMA). The results in the liquids are in good agreement with theoretical predictions and numerical simulations of previous workers, while the results in solid PMMA are 2-3 times slower. This discrepancy is discussed in the context of the rapid energetic averaging present in the liquid environments but absent in the solid matrix, where unfavorable configurations and low energy trapping sites are frozen in by the static disorder.
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BACKGROUND/PURPOSE: To compare the rate of retroprosthetic membrane (RPM) formation in Boston Keratoprosthesis (BKPro) with polymethyl methacrylate (PMMA) versus titanium backplates. DESIGN: Retrospective comparative chart review. METHODS: Multicenter study population: a total of 78 eyes with keratoprosthesis implants with either PMMA or titanium backplates were included in the study. To be included in the study, all subjects had to have completed a minimum of 6-month follow-up period. Incidence of RPM development at 6-month postoperative period was noted across the study population. PMMA and titanium backplates were then compared by their rate of association with subsequent RPM. RESULTS: Twenty-three out of 55 eyes (41.8%) with PMMA backplates and three out of 23 eyes (13.0%) with titanium backplates had developed an RPM at 6 months after implantation. The titanium backplates were associated with significantly less RPM formation than PMMA backplates (p = 0.014, Chi-square test). CONCLUSIONS: Titanium seems to be associated with less RPM formation than PMMA when used as a material for the BKPro back plate.
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Enfermedades de la Córnea/cirugía , Trasplante de Córnea/métodos , Polimetil Metacrilato , Prótesis e Implantes , Titanio , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Adulto JovenRESUMEN
PURPOSE: To report with morphologic and phylogenetic speciation the first case from Israel of Pythium insidiosum keratitis associated with contact-lens wear. METHODS: Case report and literature review. RESULTS: A 21-year-old man with a history of contact-lens use and water exposure was hospitalized in Israel for a corneal ulcer. The ulcer progressed despite intensive antibiotics. He flew home to the United States for further care. Examination revealed a corneal ulcer with hypopyon. The infection progressed despite intensive medical therapy, and a therapeutic penetrating keratoplasty was performed. Histology and cornea cultures from the host cornea revealed sparsely septate, branching hyphae, consistent with P. insidiosum. DNA sequencing of the Pythium isolate supported the clinical history that the infection was acquired outside of the United States. Despite intensive medical therapy and a second corneal transplant, the ulcer progressed, ultimately requiring enucleation. CONCLUSION: This is the first reported case of culture-proven, contact lens-related Pythium keratitis originating from Israel. Pythium is a fungus-like, aquatic oomycete found in tropical climates. Human pythiosis is uncommon but associated with high morbidity. Case reports describe surgical cure of Pythium keratitis, but this case recurred despite two penetrating keratoplasties and maximal antifungal therapy. In cases of presumed fungal keratitis that do not respond to antifungals, the fungus should be sent for speciation because early surgical intervention is the only means to save the eye in ocular pythiosis.
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Lentes de Contacto/efectos adversos , Úlcera de la Córnea/microbiología , Queratitis/microbiología , Pitiosis/complicaciones , Pitiosis/etiología , Pythium/aislamiento & purificación , Cámara Anterior , Antifúngicos/uso terapéutico , Úlcera de la Córnea/tratamiento farmacológico , Úlcera de la Córnea/patología , Úlcera de la Córnea/cirugía , Progresión de la Enfermedad , Enucleación del Ojo , Humanos , Israel , Queratoplastia Penetrante , Masculino , Pitiosis/patología , Pythium/genética , Recurrencia , Reoperación , Análisis de Secuencia de ADN , Supuración/microbiología , Adulto JovenRESUMEN
ABSTRACT: The current understanding on the clinical efficacy of Rho-associated protein kinase (ROCK) inhibitor for treating Fuchs endothelial corneal dystrophy is summarized to clarify whether the "off-label" ROCK-inhibitor eye-drop application are appropriate. ROCK-inhibitor eye drops may eventually be deemed a cutting-edge therapy for Fuchs endothelial corneal dystrophy patients with acute corneal endothelial defect.
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Distrofia Endotelial de Fuchs/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Quinasas Asociadas a rho/antagonistas & inhibidores , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/administración & dosificación , 1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Administración Oftálmica , Benzoatos/administración & dosificación , Ensayos Clínicos como Asunto , Humanos , Isoquinolinas/administración & dosificación , Soluciones Oftálmicas , Sulfonamidas/administración & dosificación , Resultado del Tratamiento , beta-Alanina/administración & dosificación , beta-Alanina/análogos & derivadosRESUMEN
Importance: Age-related macular degeneration (AMD), the leading cause of irreversible blindness in older adults, appears to have no effective preventive measures. The common antidiabetic drug metformin has been shown to have protective outcomes in multiple age-associated diseases and may have the potential to protect against the development of AMD. Objective: To determine whether metformin use is associated with reduced odds of developing AMD. Design, Setting, and Participants: This case-control study of patients from a nationwide health insurance claims database included a population-based sample of patients. Those aged 55 years and older with newly diagnosed AMD from January 2008 to December 2017 were defined as cases and matched with control participants. Data analyses were completed from June 2019 to February 2020. Exposures: Dosage of metformin and exposure to other prescribed medications, as identified from outpatient drug claims. Main Outcomes and Measures: Risk of developing AMD. Results: A total of 312â¯404 affected individuals were included (181â¯817 women [58.2%]). After matching, 312â¯376 control participants were included (172â¯459 women [55.2%]; age range, 55 to 107 years). The case group had a slightly higher percentage of participants with diabetes (81â¯262 participants [26.0%]) compared with the control group (79â¯497 participants [25.5%]). Metformin use was associated with reduced odds of developing AMD (odds ratio [OR], 0.94 [95% CI, 0.92-0.96]). This association was dose dependent, with low to moderate doses of metformin showing the greatest potential benefit (dosages over 2 years: 1-270 g, OR, 0.91 [95% CI, 0.88-0.94]; 271-600 g, OR, 0.90 [95% CI, 0.87-0.93]; 601-1080 g, OR, 0.95 [95% CI, 0.92-0.98]). Doses of more than 1080 g of metformin over 2 years did not have reduced odds of developing AMD. Both the reduction in odds ratio and the dose-dependent response were preserved in a cohort consisting only of patients with diabetes. Metformin use was associated with a decreased OR of AMD in patients with diabetes without coexisting diabetic retinopathy (OR, 0.93 [95% CI, 0.91-0.95]) but was a risk factor in patients with diabetic retinopathy (OR, 1.07 [95% CI, 1.01-1.15]). Conclusion and Relevance: In this study, metformin use was associated with reduced odds of developing AMD. This association was dose dependent, with the greatest benefit at low to moderate doses. When looking only at patients with diabetes, we saw a preservation of the dose-dependent decrease in the odds of patients developing AMD. Metformin does not appear to be protective in patients with diabetes and coexisting diabetic retinopathy. This study suggests that metformin may be useful as a preventive therapy for AMD and provides the basis for potential prospective clinical trials.
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Diabetes Mellitus/tratamiento farmacológico , Degeneración Macular/etiología , Metformina/efectos adversos , Retina/efectos de los fármacos , Medición de Riesgo/métodos , Agudeza Visual , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Incidencia , Degeneración Macular/epidemiología , Masculino , Metformina/uso terapéutico , Persona de Mediana Edad , Estudios Prospectivos , Retina/patología , Factores de Riesgo , Estados Unidos/epidemiologíaRESUMEN
Electronic energy transfer plays an important role in many types of organic electronic devices. Forster-type theories of exciton diffusion provide a way to calculate diffusion constants and lengths, but their applicability to amorphous polymer systems must be evaluated. In this paper, the perylenediimide dye Lumogen Red in a poly(methyl methacrylate) host matrix is used to test theories of exciton motion over Lumogen Red concentrations (C(LR)'s) ranging from 1 x 10(-4) to 5 x 10(-2) M. Two experimental quantities are measured. First, time-resolved anisotropy decays in films containing only Lumogen Red provide an estimate of the initial energy transfer rate from the photoexcited molecule. Second, the Lumogen Red lifetime decays in mixed systems where the dyes Malachite Green and Rhodamine 700 act as energy acceptors are measured to estimate the diffusive quenching of the exciton. From the anisotropy measurements, it is found that theory accurately predicts both the C(LR)(-2) concentration dependence of the polarization decay time tau(pol), as well as its magnitude to within 30%. The theory also predicts that the diffusive quenching rate is proportional to C(LR)(alpha), where alpha ranges between 1.00 and 1.33. Experimentally, it is found that alpha = 1.1 +/- 0.2 when Malachite Green is used as an acceptor, and alpha = 1.2 +/- 0.2 when Rhodamine 700 is the acceptor. On the basis of the theory that correctly describes the anisotropy data, the exciton diffusion constant is projected to be 4-9 nm(2)/ns. By use of several different analysis methods for the quenching data, the experimental diffusion constant is found to be in the range of 0.32-1.20 nm(2)/ns. Thus the theory successfully describes the early time anisotropy data but fails to quantitatively describe the quenching experiments which are sensitive to motion on longer time scales. The data are consistent with the idea that orientational and energetic disorder leads to a time-dependent exciton migration rate, suggesting that simple diffusion models cannot accurately describe exciton motion within this system.
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Fuchs endothelial corneal dystrophy (FECD) is the most common posterior corneal dystrophy and the leading indication for corneal transplantation in the United States. FECD is slowly progressive, and patients develop gradual corneal endothelial decompensation, eventually resulting in failure of the endothelium to maintain corneal deturgescence. Medical management consists of topical hyperosmotic agents to facilitate dehydration of the cornea, but surgical intervention is often required to regain corneal clarity. The surgical management of FECD has evolved over the past two decades as corneal transplantation techniques have allowed for more selective keratoplasty and replacement of only the diseased layers of the cornea. Prior surgical management consisted of penetrating keratoplasty (PK) that carried significant intraoperative risks associated with "open sky" as well as postoperative risks of graft rejection, wound dehiscence, postoperative astigmatism, and prolonged visual rehabilitation. In the past 15 years, endothelial keratoplasty (EK) has become the treatment of choice for endothelial disease, significantly reducing the risks associated with the surgical treatment of FECD. Here we discuss the current surgical management of FECD, including the introduction of Descemet stripping only (DSO), and highlight future investigative efforts.
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PURPOSE: To quantitatively analyze the angle anatomy in eyes with a Boston type 1 keratoprosthesis (KPro) using anterior segment optical coherence tomography (AS-OCT) and to assess the diagnostic ability of AS-OCT in KPro-associated glaucoma. METHODS: AS-OCT (RTVue) images from KPro eyes with and without glaucoma were reviewed. The angle opening distance at 500 µm from the scleral spur (AOD500), trabecular-iris angle at 500 µm from the scleral spur (TIA500), and trabecular-iris surface area at 500 µm from the scleral spur (TISA500) were measured by 2 observers masked to the diagnosis. The measurements for each visible quadrant were compared between KPro eyes with and without glaucoma. RESULTS: Twenty-two eyes with glaucoma and 17 eyes without glaucoma from 39 patients with KPro were included. Of the 4 quadrants imaged, the temporal angle was the most visible (79.5%) and angle measurements of the temporal quadrant were the only ones that differentiated the 2 groups: the mean AOD500, TIA500, and TISA500 were significantly lower in KPro eyes with glaucoma than without glaucoma (388.2 ± 234.4 µm vs. 624.5 ± 310.5 µm, P = 0.02; 26.1 ± 14.0 degrees vs. 39.1 ± 17.1 degrees, P = 0.03; and 0.15 ± 0.09 mm vs. 0.23 ± 0.12 mm, P = 0.03; respectively). The highest area under the receiver operating characteristic curve for detecting glaucoma was 0.75 for temporal TIA500 (95% confidence interval 0.57-0.94, P = 0.02) with 50% specificity at 80% of sensitivity and a cutoff value of 37 degrees. CONCLUSIONS: The temporal angle was the most visible on AS-OCT in eyes with a KPro. Significant narrowing of the temporal angle detected on AS-OCT was associated with glaucoma in these eyes.
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Córnea/diagnóstico por imagen , Enfermedades de la Córnea/cirugía , Glaucoma/diagnóstico , Gonioscopía/métodos , Presión Intraocular/fisiología , Prótesis e Implantes/efectos adversos , Tomografía de Coherencia Óptica/métodos , Anciano , Córnea/cirugía , Enfermedades de la Córnea/diagnóstico , Estudios Transversales , Femenino , Estudios de Seguimiento , Glaucoma/etiología , Glaucoma/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Falla de Prótesis , Estudios RetrospectivosRESUMEN
This report describes the corneal pathology in an infant with newborn primary congenital glaucoma and discusses whether these findings could be due to a developmental anomaly. The corneal specimen of a 4-month-old infant with newborn primary congenital glaucoma and cloudy corneas who had undergone penetrating keratoplasty was evaluated by light and electron microscopy. Light microscopy showed a thinned epithelium, areas of thickened Bowman's layer (approximately 27 mum thick) interspersed with nuclei, and a thickened and disorganized stroma. Descemet's membrane was intact, and the endothelium was mildly attenuated. The corneal changes seen in this patient may be specific to primary congenital glaucoma and may contribute to the corneal clouding seen so frequently in these patients.
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Córnea/anomalías , Enfermedades de la Córnea/congénito , Glaucoma/congénito , Córnea/ultraestructura , Enfermedades de la Córnea/diagnóstico , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Glaucoma/diagnóstico , Humanos , Recién Nacido , Presión Intraocular , Microscopía Electrónica , Tonometría OcularRESUMEN
PURPOSE: To assess outcomes and glaucoma management in eyes with aniridia following Boston type 1 Keratoprosthesis (KPro) implantation. DESIGN: Retrospective, interventional comparative case series. METHODS: The population included patients with aniridia and patients with other preoperative diagnoses (excluding Stevens-Johnson syndrome, mucous membrane pemphigoid, and congenital disorders) who underwent KPro implantation at Massachusetts Eye and Ear with at least 2 years of follow-up. One eye per patient was selected based on the longer follow-up time. The main outcome was intermediate and long-term outcomes related to glaucoma. RESULTS: The aniridia (n = 22) and comparison (n = 61) groups had similar preoperative visual acuity (VA, mean ± standard deviation, 1.86 ± 0.52 logMAR, P = .33) and follow-up time (65.6 ± 26.3 months, P = .25). Before KPro implantation, eyes with aniridia had more glaucoma (76.2%) and glaucoma surgery (57.1%) than comparison eyes (51.8%, P = .053; 23.2%, P = .005, respectively). More Ahmed valves were co-implanted with KPro in aniridia (47.6%) vs comparison eyes (17.9%, P = .008). At final follow-up, more aniridia eyes had glaucoma (90.5%) than comparison eyes (64.3%, P = .02), but the 2 groups had similar percentages of eyes with cup-to-disc ratio (CDR) >0.8 (23.8% vs. 30.4%, P = .57) or CDR progression of ≥0.2 (42.9% vs 44.6%, P = .89, respectively). None of the eyes with prophylactic tube implantation developed glaucoma. Eyes with and without aniridia did not differ in post-KPro VA improvement (72.7%, 72.1%, P = .96), and final VA (1.28 ± 0.79 logMAR, 1.23 ± 0.98 logMAR, P = .51). CONCLUSION: Despite a higher glaucoma prevalence, eyes with aniridia achieved similar VA as comparison eyes with more than 5 years of mean follow-up time. Boston KPro offers satisfactory visual rehabilitation in aniridia when glaucoma is managed aggressively.
Asunto(s)
Aniridia/complicaciones , Órganos Artificiales , Enfermedades de la Córnea/cirugía , Implantes de Drenaje de Glaucoma , Glaucoma/cirugía , Complicaciones Posoperatorias , Prótesis e Implantes , Adulto , Anciano , Córnea , Femenino , Estudios de Seguimiento , Glaucoma/etiología , Glaucoma/fisiopatología , Humanos , Presión Intraocular/fisiología , Masculino , Persona de Mediana Edad , Implantación de Prótesis , Estudios Retrospectivos , Tonometría Ocular , Agudeza Visual/fisiologíaRESUMEN
Conjunctival nevi in children and adolescents often have histologic features that can be difficult to differentiate from malignancy. We have identified a subset of childhood nevi displaying a confluent growth pattern and a lack of maturation that we have defined as juvenile conjunctival nevi (JCN), with the aim of further describing the clinicopathologic features of these lesions. Lesions identified as conjunctival nevus in a tertiary referral hospital were reviewed and the subset of lesions identified as JCN were further evaluated. Clinical details including follow-up data were also gathered. Of the 40 conjunctival nevi identified, 33 fit the criteria for JCN. The mean age at time of excision was 10.9 years (range: 4 to 19 y). Thirty-two lesions were of the compound type; one was a junctional nevus. All showed a nested junctional growth pattern. In 17 lesions (61%), the junctional component extended beyond the subepithelial component (shoulder phenomenon). Maturation was absent in 21 of the compound nevi (66%, average age 10.3 y), and incomplete in the remaining 11 lesions (34%, average age 12.1 y). The nuclei of the subepithelial nevus cells were larger than the epithelial nevus cells in 19 nevi (59%) and the same size in 13 (41%). A lymphocytic host response was present in 17 lesions (52%). Mitotic figures were rarely seen. None of the lesions had recurred over an average follow-up period of 34 months. Recognition of JCN as a distinct morphologic variant of a conjunctival nevus with characteristic histologic features may help to distinguish this benign lesion from melanoma.