WorldWideScience

Sample records for cornea

  1. Cornea Transplant

    Science.gov (United States)

    ... died from an unknown cause. During your cornea transplant On the day of your cornea transplant, you' ... when you see your eye doctor. Procedures to transplant a portion of the cornea With some types ...

  2. Cloudy cornea

    Science.gov (United States)

    ... of lid tissue Computer mapping of the cornea (corneal topography) Schirmer's test for eye dryness Special photographs to measure the cells of the cornea Standard eye exam Ultrasound to measure corneal thickness ...

  3. The cornea in measles

    NARCIS (Netherlands)

    N.W.H.M. Dekkers (Nico)

    1981-01-01

    textabstractThe involvement of the cornea in the acute stage of measles is the subject of the present study. The best study on the measles-keratitis now available is still the one by Trantas in 1903. It seems wo.:thwhile therefore to study this self-limiting keratitis with the investigative tools

  4. The cornea in measles

    NARCIS (Netherlands)

    N.W.H.M. Dekkers (Nico)

    1981-01-01

    textabstractThe involvement of the cornea in the acute stage of measles is the subject of the present study. The best study on the measles-keratitis now available is still the one by Trantas in 1903. It seems wo.:thwhile therefore to study this self-limiting keratitis with the investigative tools no

  5. Phototoxicity and the cornea.

    Science.gov (United States)

    Schein, O D

    1992-07-01

    The cornea is sensitive to the effects of ultraviolet (UV) light and can suffer both acute and chronic toxicity. Ultraviolet keratitis is associated with relatively short exposures to light sources such as welding arcs or tanning lamps. The corneal effects are seen within a few hours following exposure and typically will resolve within 72 hours. Chronic exposure to environmental UV light may lead to a variety of ocular surface abnormalities that rarely resolve in the absence of therapy. Ultraviolet light, while potentially destructive, also can be used therapeutically. Recently, the photoablative properties of the excimer laser have been used in corneal refractive surgery. This laser uses UV light to break chemical bonds and remove tissue. Corneal phototoxicity is a reflection of the sensitivity of the ocular surface to photochemical injury. Fortunately, effective protection in the form of UV-blocking lenses is widely available.

  6. [The cornea: stasis and dynamics].

    Science.gov (United States)

    Nishida, Teruo

    2008-03-01

    The physiological roles of the cornea are to conduct external light into the eye, focus it, together with the lens, onto the retina, and to provide rigidity to the entire eyeball. Good vision thus requires maintenance of the transparency and proper refractive shape of the cornea. Although the cornea appears to be a relatively static structure, dynamic processes operate within and around the cornea at the tissue, cell, and molecular level. In this article, I review the mechanisms responsible for maintenance of corneal homeostasis as well as the development of new modes of treatment for various corneal diseases. I. The static cornea: structure and physiological functions. The cornea is derived from ectoderm, so that it can be considered as transparent skin. It is devoid of blood vessels and manifests the highest sensitivity in the entire body. The surface of the cornea is covered by tear fluid, which serves both as a lubricant and as a conduit for regulatory molecules. The cornea is also supplied with oxygen and various nutrients by the aqueous humor and a loop vascular system in addition to tear fluid. The cornea interacts with its surrounding tissues directly as well as indirectly through tear fluid or aqueous humor, with such interactions playing an important role in the regulation of corneal structure and functions. The resident cells of the cornea-epithelial cells, fibroblasts (keratocytes), and endothelial cells--also engage in mutual interactions through network systems. These interactions as well as those with infiltrated cells and regulation by nerves contribute to the maintenance of the normal structure and functions of the cornea as well as to the repair of corneal injuries. II. The dynamic cornea: maintenance of structure and functions by network systems. Developments in laser and computer technology have allowed observation of the cells and collagen fibers within the cornea. Furthermore, progress in cell and molecular biology has allowed characterization

  7. Spheroidal Degeneration of the Cornea

    Directory of Open Access Journals (Sweden)

    Erdem Dinç

    2011-08-01

    Full Text Available A thirty-one-year-old male patient presented with bilateral epiphora and stinging sensation in the cornea. Detailed history revealed that a bilateral corneal scraping had been made regarding the initial diagnosis of fungal keratitis. His bestcorrected visual acuities were 20/20 and 20/30 in right and left eyes, respectively. Biomicroscopy showed bilateral amber colored spherules in the anterior stroma of the central cornea. The diagnosis of spheroidal corneal degeneration was established and symptomatic therapy with artificial tear drops was prescribed. Ultraviolet light is widely accepted to be the main etiological factor in the pathogenesis of spheroidal degeneration. Because of difficulties in the early stages of the diagnostic process of the disease, incorrect diagnoses can be made with inappropriate interventions. (Turk J Ophthalmol 2011; 41: 264-6

  8. Bee sting of the cornea.

    Science.gov (United States)

    Singh, G

    1984-04-01

    Irreversible heterochromia-iridis, internal ophthalmoplegia, and punctate subcapsular lenticular opacities developed in a 9-year-old girl after she received a bee sting in her right cornea. These complications persisted even after an 11-month follow-up period. To the author's knowledge, this presentation is the first of its nature. The pathogenesis of these changes is discussed and the literature is reviewed.

  9. Cornea and ocular surface treatment.

    Science.gov (United States)

    De Miguel, Maria P; Alio, Jorge L; Arnalich-Montiel, Francisco; Fuentes-Julian, Sherezade; de Benito-Llopis, Laura; Amparo, Francisco; Bataille, Laurent

    2010-06-01

    In addition to being a protective shield, the cornea represents two thirds of the eye's refractive power. Corneal pathology can affect one or all of the corneal layers, producing corneal opacity. Although full corneal thickness keratoplasty has been the standard procedure, the ideal strategy would be to replace only the damaged layer. Current difficulties in corneal transplantation, mainly immune rejection and shortage of organ supply, place more emphasis on the development of artificial corneas. Bioengineered corneas range from prosthetic devices that solely address the replacement of the corneal function, to tissue-engineered hydrogels that allow regeneration of the tissue. Recently, major advances in the biology of corneal stem cells have been achieved. However, the therapeutic use of these stem cell types has the disadvantage of needing an intact stem cell compartment, which is usually damaged. In addition, long ex vivo culture is needed to generate enough cell numbers for transplantation. In the near future, combination of advanced biomaterials with cells from abundant outer sources will allow advances in the field. For the former, magnetically aligned collagen is one of the most promising ones. For the latter, different cell types will be optimal: 1) for epithelial replacement: oral mucosal epithelium, ear epidermis, or bone marrow- mesenchymal stem cells, 2) for stromal regeneration: adipose-derived stem cells and 3) for endothelial replacement, the possibility of in vitro directed differentiation of adipose-derived stem cells towards endothelial cells provides an exciting new approach.

  10. Anatomy and physiology of the cornea.

    Science.gov (United States)

    DelMonte, Derek W; Kim, Terry

    2011-03-01

    The importance of the cornea to the ocular structure and visual system is often overlooked because of the cornea's unassuming transparent nature. The cornea lacks the neurobiological sophistication of the retina and the dynamic movement of the lens; yet, without its clarity, the eye would not be able to perform its necessary functions. The complexity of structure and function necessary to maintain such elegant simplicity is the wonder that draws us to one of the most important components of our visual system.

  11. Synthetic cornea: biocompatibility and optics

    Science.gov (United States)

    Parel, Jean-Marie A.; Kaminski, Stefan; Fernandez, Viviana; Alfonso, E.; Lamar, Peggy; Lacombe, Emmanuel; Duchesne, Bernard; Dubovy, Sander; Manns, Fabrice; Rol, Pascal O.

    2002-06-01

    Purpose. Experimentally find a method to provide a safe surgical technique and an inexpensive and long lasting mesoplant for the restoration of vision in patients with bilateral corneal blindness due to ocular surface and stromal diseases. Methods. Identify the least invasive and the safest surgical technique for synthetic cornea implantation. Identify the most compatible biomaterials and the optimal shape a synthetic cornea must have to last a long time when implanted in vivo. Results. Penetrating procedures were deemed too invasive, time consuming, difficult and prone to long term complications. Therefore a non-penetrating delamination technique with central trephination was developed to preserve the integrity of Descemet's membrane and the anterior segment. Even though this approach limits the number of indications, it is acceptable since the majority of patients only have opacities in the stroma. The prosthesis was designed to fit in the removed tissue plane with its skirt fitted under the delaminated stroma. To improve retention, the trephination wall was made conical with the smallest opening on the anterior surface and a hat-shaped mesoplant was made to fit. The skirt was perforated in its perimeter to allow passage of nutrients and tissues ingrowths. To simplify the fabrication procedure, the haptic and optic were made of the same polymer. The intrastromal biocompatibility of several hydrogels was found superior to current clinically used PMMA and PTFE materials. Monobloc mesoplants made of 4 different materials were implanted in rabbits and followed weekly until extrusion occurred. Some remained optically clear allowing for fundus photography. Conclusions. Hydrogel synthetic corneas can be made to survive for periods longer than 1 year. ArF excimer laser photoablation studies are needed to determine the refractive correction potential of these mesoplants. A pilot FDA clinical trial is needed to assess the mesoplant efficacy and very long-term stability.

  12. Lymphangiogenesis Occurring in Transplanted Corneas

    Institute of Scientific and Technical Information of China (English)

    LING Shiqi; XIAO Qing; HU Yanhua

    2006-01-01

    To study corneal lymphangiogenesis after corneal transplantation, corneal allogenic transplantation models were established in rats. 8 female Wister rats were used as donors, and 16 Sprague Dawley (SD) rats were used as recipients and 2 SD served as controls. Corneal lymphangiogenesis and hemangiogenesis was examined by electron microscopy 1 and 2 weeks after corneal penetrating transplantation, and the expression of lymphatic vessel endothelial receptor (LYVE-1) was examined 1, 3, 7, 14 days after the transplantation respectively. In addition, 19 allograft failed human corneas were examined by 5'-nase-alkaline phosphatase (5'-NA-ALP) doubleenzyme-histochemistry staining to detect corneal lymphangiogenesis and hemangiogenesis. By immunohistochemistry for LYVE-1, it was found that blown lymphatics were localized in the stroma 3days after the corneal transplantation. With electron microscopy, new lymphatic vessels and blood vessels were found 1 and 2 weeks after the corneal transplantation. By 5'-NA-ALP enzyme-histochemistry, corneal hemangiogenesis was found in all allograft failed huma n corneas and 5 of 19(26.3%) cases had developed corneal lymphangiogenesis. It is concluded that corneal lymphangiogenesis is present after corneal transplantation, which may play an important role in allograft rejection.

  13. Gene therapy in the cornea.

    Science.gov (United States)

    Mohan, Rajiv R; Sharma, Ajay; Netto, Marcelo V; Sinha, Sunilima; Wilson, Steven E

    2005-09-01

    Technological advances in the field of gene therapy has prompted more than three hundred phase I and phase II gene-based clinical trials for the treatment of cancer, AIDS, macular degeneration, cardiovascular, and other monogenic diseases. Besides treating diseases, gene transfer technology has been utilized for the development of preventive and therapeutic vaccines for malaria, tuberculosis, hepatitis A, B and C viruses, AIDS, and influenza. The potential therapeutic applications of gene transfer technology are enormous. The cornea is an excellent candidate for gene therapy because of its accessibility and immune-privileged nature. In the last two decades, various viral vectors, such as adeno, adeno-associated, retro, lenti, and herpes simplex, as well as non-viral methods, were examined for introducing DNA into corneal cells in vitro, in vivo and ex vivo. Most of these studies used fluorescent or non-fluorescent marker genes to track the level and duration of transgene expression in corneal cells. However, limited studies were directed to evaluate prospects of gene-based interventions for corneal diseases or disorders such as allograft rejection, laser-induced post-operative haze, herpes simplex keratitis, and wound healing in animal models. We will review the successes and obstacles impeding gene therapy approaches used for delivering genes into the cornea.

  14. Bioengineered Corneas Grafted as Alternatives to Human Donor Corneas in Three High‐Risk Patients

    National Research Council Canada - National Science Library

    Buznyk, Oleksiy; Pasyechnikova, Nataliya; Islam, M. Mirazul; Iakymenko, Stanislav; Fagerholm, Per; Griffith, May

    2015-01-01

    .... In this early observational study, we grafted bioengineered corneal implants made from recombinant human collagen and synthetic phosphorylcholine polymer into three patients for whom donor cornea...

  15. Construction of Tissue Engineering Artificial Cornea with Skin Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Yuan LIU; Yan JIN

    2005-01-01

    @@ 1 Introduction The clinical need for an alternative to donor corneal tissue has encouraged much interests in recent years. An artificial cornea must fulfill the functions of the cornea it replaces. More recently, the idea of a bio-engineered cornea has risen. Corneal equivalents have been reconstructed by tissue engineering method. Aim of this study is to construct an artificial rabbit cornea by employing tissue engineering method and to determine if skin stem cells have a role in tissue engineered cornea construction.

  16. Designing a perfect cornea: computational aspects

    Science.gov (United States)

    Rubinstein, Jacob; Wolansky, Gershon

    2002-12-01

    We analyze an algorithm for the design of a perfect cornea that exactly focuses a preselected object or a preselected wave front on the retina. The algorithm can be used, for example, in refractive surgery. We consider the sensitivity of the algorithm to various errors, including errors in the measurements of the aberrations, the original corneal topography and the ablation process.

  17. Construction of Tissue Engineering Artificial Cornea with Skin Stem Cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    1 IntroductionThe clinical need for an alternative to donor corneal tissue has encouraged much interests in recent years. An artificial cornea must fulfill the functions of the cornea it replaces. More recently, the idea of a bio-engineered cornea has risen. Corneal equivalents have been reconstructed by tissue engineering method. Aim of this study is to construct an artificial rabbit cornea by employing tissue engineering method and to determine if skin stem cells have a role in tissue engineered cornea co...

  18. [Effect of phacoemulsification on the cornea].

    Science.gov (United States)

    Stănilă, D M; Stănilă, Adriana; Mihai, Elena; Sîrbu, N G; Stupariu, A L

    2013-01-01

    Cataracta is the more common surgical diesease of the eye. The removal of the cataract is done my phacoemulsification. To evaluate the effect of phacoemulsifcation on the cornea. We have studied 80 patients with cataract that underwent cataract surgery by phacoemulsification. We measured the corneal thickness and the number of endothelial cell before and after the surgery. REZULTS AND DISCUSSIONS: Corneal thickness grew with 3% and the number of endothelial cells decresed with 13%. Phacoemulsification with the use of vascoelastic substancees is a very safe method of lens extraction

  19. Awareness of Cornea Donation of Registered Tissue Donors in Nanjing

    Institute of Scientific and Technical Information of China (English)

    Ting Chu; Lin-nong Wang; Hao Yu; Ru-yang Zhang

    2013-01-01

    Objective To evaluate the current cornea donation awareness of tissue donors in the city of Nanjing,China. Methods Altogether 2000 registered tissue donors in the Red Cross Eye Bank of Nanjing by the end of 2010 and 2000 control residents of Nanjing in February to June 2011 were randomly selected to par-ticipate in our field questionnaire survey. The questionnaire consisted of questions regarding the understand-ing of cornea donation,the attitude toward cornea donation,and attitude toward legislation and free dona-tion. The awareness of cornea donation between the registered tissue donors and residents was compared. Related factors of the willingness to donate corneas and to become a tissue donor were evaluated with uni-variate and multiple logistic regression analysis. Results A total of 1867 (response rate: 93.4%) tissue donors and 1796 (response rate: 89.8%; ef-fective questionnaires: 1697) residents participated in this survey. For the questions about the knowledge of cornea donation,90.3% tissue donors (residents: 78.9%) knew that donated corneas could be used for transplantations; 71.2% tissue donors (residents: 47.6%) knew that the appearance would not be destroyed after cornea donation; 70.7% tissue donors (residents: 20.0%) knew the formalities to become a cornea do-nor. For attitude toward cornea donation,82.2% tissue donors (residents: 45.1%) were willing to donate corneas or eyeballs after death; 84.0% tissue donors (residents: 30.2%) had discussed with their families about donation; 85.1% tissue donors (residents: 24.8%) supported their families' or friends' cornea donation. For attitude toward legislation and free donation,88.3% tissue donors (residents: 61.3%) approved of legis-lation to regular cornea donation; 72.2% tissue donors (residents: 38.8%) thought that cornea or organ do-nation should be gratis. The difference between two groups was significant (P<0.001). However,some tissue donors did not know cornea donation well,some even opposed the

  20. Investigation of Friction-induced Damage to the Pig Cornea

    NARCIS (Netherlands)

    da Cruz Barros, Raquel; Van Kooten, Theo G.; Veeregowda, Deepak Halenahally

    2015-01-01

    Mechanical friction causes damage to the cornea. A friction measurement device with minimal intervention with the pig cornea tear film revealed a low friction coefficient of 0.011 in glycerine solution. Glycerine molecules presumably bind to water, mucins, and epithelial cells and therewith improve

  1. Investigation of Friction-induced Damage to the Pig Cornea

    NARCIS (Netherlands)

    da Cruz Barros, Raquel; Van Kooten, Theo G.; Veeregowda, Deepak Halenahally

    2015-01-01

    Mechanical friction causes damage to the cornea. A friction measurement device with minimal intervention with the pig cornea tear film revealed a low friction coefficient of 0.011 in glycerine solution. Glycerine molecules presumably bind to water, mucins, and epithelial cells and therewith improve

  2. Customized Finite Element Modelling of the Human Cornea.

    Directory of Open Access Journals (Sweden)

    Irene Simonini

    Full Text Available To construct patient-specific solid models of human cornea from ocular topographer data, to increase the accuracy of the biomechanical and optical estimate of the changes in refractive power and stress caused by photorefractive keratectomy (PRK.Corneal elevation maps of five human eyes were taken with a rotating Scheimpflug camera combined with a Placido disk before and after refractive surgery. Patient-specific solid models were created and discretized in finite elements to estimate the corneal strain and stress fields in preoperative and postoperative configurations and derive the refractive parameters of the cornea.Patient-specific geometrical models of the cornea allow for the creation of personalized refractive maps at different levels of IOP. Thinned postoperative corneas show a higher stress gradient across the thickness and higher sensitivity of all geometrical and refractive parameters to the fluctuation of the IOP.Patient-specific numerical models of the cornea can provide accurate quantitative information on the refractive properties of the cornea under different levels of IOP and describe the change of the stress state of the cornea due to refractive surgery (PRK. Patient-specific models can be used as indicators of feasibility before performing the surgery.

  3. Estimation of the surface tension of ocular cornea

    Science.gov (United States)

    Zhang, Xueyong; Ma, Jianguo; Lu, Rongsheng; Xia, Ruixue

    2008-12-01

    Considering the potential clinical importance, the surface tension of ocular cornea under the action of normal physiological intraocular pressure is estimated, and a novel technique and a simple mechanical model for determining the tension are also presented in this paper. An instrument embodying mainly a CCD camera, an optical staff gauge and a manometer was developed primarily to measure both the surface point displacement and intraocular pressure of the cornea. A simple theoretical model was used to characterize the tensions of the ocular corneas under the action of the intraocular pressure. Due to the difficulty in obtaining the human cornea, laboratory experiments were carried out on porcine cornea specimens. The thickness of the specimens was accurately measured by optical coherence tomography. The matrix and collagen properties within the corneal tissue were manifested in the experiment. Experimental results on porcine corneas showed that the present technique is applicable to estimate the surface tension. In the normal physiological intraocular pressure range, both meridian and circumference tensions of the porcine corneas along the radial coordinate distribute are not uniform.

  4. Extracellular matrix alterations in human corneas with bullous keratopathy

    DEFF Research Database (Denmark)

    Ljubimov, A V; Burgeson, R E; Butkowski, R J

    1996-01-01

    . RESULTS. Fibrillar deposits of an antiadhesive glycoprotein tenascin in the anterior and posterior stroma, epithelial basement membrane (BM), bullae and subepithelial fibrosis (SEF) areas, and posterior collagenous layer (PCL) were revealed in disease corneas. Tenascin in midstroma, which was observed...

  5. Collagen cross-linking in thin corneas

    Directory of Open Access Journals (Sweden)

    Prema Padmanabhan

    2013-01-01

    Full Text Available Collagen cross-linking (CXL has become the standard of care for progressive keratoconus, after numerous clinical studies have established its efficacy and safety in suitably selected eyes. The standard protocol is applicable in eyes which have a minimum corneal thickness of 400 μm after epithelial debridement. This prerequisite was stipulated to protect the corneal endothelium and intraocular tissues from the deleterious effect of ultraviolet-A (UVA radiation. However, patients with keratoconus often present with corneal thickness of less than 400 μm and could have otherwise benefited from this procedure. A few modifications of the standard procedure have been suggested to benefit these patients without a compromise in safety. Transepithelial cross-linking, pachymetry-guided epithelial debridement before cross-linking, and the use of hypoosmolar riboflavin are some of the techniques that have been attempted. Although clinical data is limited at the present time, these techniques are worth considering in patients with thin corneas. Further studies are needed to scientifically establish their efficacy and safety.

  6. Measurement of the anisotropic thermal conductivity of the porcine cornea.

    Science.gov (United States)

    Barton, Michael D; Trembly, B Stuart

    2013-10-01

    Accurate thermal models for the cornea of the eye support the development of thermal techniques for reshaping the cornea and other scientific purposes. Heat transfer in the cornea must be quantified accurately so that a thermal treatment does not destroy the endothelial layer, which cannot regenerate, and yet is responsible for maintaining corneal transparency. We developed a custom apparatus to measure the thermal conductivity of ex vivo porcine corneas perpendicular to the surface and applied a commercial apparatus to measure thermal conductivity parallel to the surface. We found that corneal thermal conductivity is 14% anisotropic at the normal state of corneal hydration. Small numbers of ex vivo feline and human corneas had a thermal conductivity perpendicular to the surface that was indistinguishable from the porcine corneas. Aqueous humor from ex vivo porcine, feline, and human eyes had a thermal conductivity nearly equal to that of water. Including the anisotropy of corneal thermal conductivity will improve the predictive power of thermal models of the eye. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Portable light transmission measuring system for preserved corneas

    Science.gov (United States)

    Ventura, Liliane; de Jesus, Gabriel Torres; de Oliveira, Gunter Camilo Dablas; Sousa, Sidney JF

    2005-01-01

    Background The authors have developed a small portable device for the objective measurement of the transparency of corneas stored in preservative medium, for use by eye banks in evaluation prior to transplantation. Methods The optical system consists of a white light, lenses, and pinholes that collimate the white light beams and illuminate the cornea in its preservative medium, and an optical filter (400–700 nm) that selects the range of the wavelength of interest. A sensor detects the light that passes through the cornea, and the average corneal transparency is displayed. In order to obtain only the tissue transparency, an electronic circuit was built to detect a baseline input of the preservative medium prior to the measurement of corneal transparency. The operation of the system involves three steps: adjusting the "0 %" transmittance of the instrument, determining the "100 %" transmittance of the system, and finally measuring the transparency of the preserved cornea inside the storage medium. Results Fifty selected corneas were evaluated. Each cornea was submitted to three evaluation methods: subjective classification of transparency through a slit lamp, quantification of the transmittance of light using a corneal spectrophotometer previously developed, and measurement of transparency with the portable device. Conclusion By comparing the three methods and using the expertise of eye bank trained personnel, a table for quantifying corneal transparency with the new device has been developed. The correlation factor between the corneal spectrophotometer and the new device is 0,99813, leading to a system that is able to standardize transparency measurements of preserved corneas, which is currently done subjectively. PMID:16372912

  8. Nerve repulsion by the lens and cornea during cornea innervation is dependent on Robo-Slit signaling and diminishes with neuron age.

    Science.gov (United States)

    Schwend, Tyler; Lwigale, Peter Y; Conrad, Gary W

    2012-03-01

    The cornea, the most densely innervated tissue on the surface of the body, becomes innervated in a series of highly coordinated developmental events. During cornea development, chick trigeminal nerve growth cones reach the cornea margin at embryonic day (E)5, where they are initially repelled for days from E5 to E8, instead encircling the corneal periphery in a nerve ring prior to entering on E9. The molecular events coordinating growth cone guidance during cornea development are poorly understood. Here we evaluated a potential role for the Robo-Slit nerve guidance family. We found that Slits 1, 2 and 3 expression in the cornea and lens persisted during all stages of cornea innervation examined. Robo1 expression was developmentally regulated in trigeminal cell bodies, expressed robustly during nerve ring formation (E5-8), then later declining concurrent with projection of growth cones into the cornea. In this study we provide in vivo and in vitro evidence that Robo-Slit signaling guides trigeminal nerves during cornea innervation. Transient, localized inhibition of Robo-Slit signaling, by means of beads loaded with inhibitory Robo-Fc protein implanted into the developing eyefield in vivo, led to disorganized nerve ring formation and premature cornea innervation. Additionally, when trigeminal explants (source of neurons) were oriented adjacent to lens vesicles or corneas (source of repellant molecules) in organotypic tissue culture both lens and cornea tissues strongly repelled E7 trigeminal neurites, except in the presence of inhibitory Robo-Fc protein. In contrast, E10 trigeminal neurites were not as strongly repelled by cornea, and presence of Robo-Slit inhibitory protein had no effect. In full, these findings suggest that nerve repulsion from the lens and cornea during nerve ring formation is mediated by Robo-Slit signaling. Later, a shift in nerve guidance behavior occurs, in part due to molecular changes in trigeminal neurons, including Robo1 downregulation

  9. Biomechanical Measurement of Rabbit Cornea by a Modified Scheimpflug Device

    Science.gov (United States)

    Zhang, Bo; Gu, Jianjun; Zhang, Xiaoxiao; Yang, Bin

    2016-01-01

    Purpose. To explore the probability and variation in biomechanical measurements of rabbit cornea by a modified Scheimpflug device. Methods. A modified Scheimpflug device was developed by imaging anterior segment of the model imitating the intact eye at various posterior pressures. The eight isolated rabbit corneas were mounted on the Barron artificial chamber and images of the anterior segment were taken at posterior pressures of 15, 30, 45, 60, and 75 mmHg by the device. The repeatability and reliability of the parameters including CCT, ACD, ACV, and CV were evaluated at each posterior pressure. All the variations of the parameters at the different posterior pressures were calculated. Results. All parameters showed good intraobserver reliability (Cronbach's alpha; intraclass correlation coefficient, α, ICC > 0.96) and repeatability in the modified Scheimpflug device. With the increase of posterior pressures, the ratio of CCT decreased linearly and the bulk modulus gradually reduced to a platform. The increase of ACD was almost linear with the posterior pressures elevated. Conclusions. The modified Scheimpflug device was a valuable tool to investigate the biomechanics of the cornea. The posterior pressure 15–75 mmHg range produced small viscoelastic deformations and nearly linear pressure-deformation response in the rabbit cornea. PMID:27446608

  10. File list: ALL.Oth.10.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.10.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX248302,SRX43763...6,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.10.AllAg.Cornea.bed ...

  11. File list: ALL.Oth.50.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.50.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX437636,SRX24830...2,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.50.AllAg.Cornea.bed ...

  12. File list: ALL.Oth.20.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.20.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX437636,SRX24830...2,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.20.AllAg.Cornea.bed ...

  13. File list: ALL.Oth.05.AllAg.Cornea [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Oth.05.AllAg.Cornea mm9 All antigens Others Cornea SRX437637,SRX437636,SRX24830...2,SRX248301,SRX437638 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Oth.05.AllAg.Cornea.bed ...

  14. The transparent lens and cornea in the mouse and zebra fish eye.

    Science.gov (United States)

    Greiling, Teri M S; Clark, John I

    2008-04-01

    The lens and cornea combine to form a single optical element in which transparency and refraction are the fundamental biophysical characteristics required for a functional visual system. Although lens and cornea have different cellular and extracellular specializations that contribute to transparency and refraction, their development is closely related. In the embryonic mouse, the developing cornea and lens separate early. In contrast, zebra fish lens and cornea remain connected during early development and the optical properties of the cornea and lens observed by slit lamp and quasielastic laser light scattering spectroscopy (QLS) are more similar in the zebra fish eye than in the mouse eye. Optical similarities between cornea and lens of zebra fish may be the result of similarities in the cellular development of the cornea and lens.

  15. Acanthamoeba castellanii: morphological analysis of the interaction with human cornea.

    Science.gov (United States)

    Omaña-Molina, Maritza; González-Robles, Arturo; Salazar-Villatoro, Lizbeth Iliana; Cristóbal-Ramos, Ana Ruth; González-Lázaro, Mónica; Salinas-Moreno, Edmundo; Méndez-Cruz, Rene; Sánchez-Cornejo, Manuel; De la Torre-González, Enrique; Martínez-Palomo, Adolfo

    2010-09-01

    The present study demonstrates that when Acanthamoeba castellanii trophozoites are co-cultivated with isolated human corneas, the amoeba can be invasive and cause damage to the intact corneal epithelium without the requirement of previous corneal abrasion. After adhesion, A. castellanii trophozoites migrate between cells forming bumps on the corneal cell layers and reaching Bowman s membrane in 3h, although no evidence of cell damage was observed until the phagocytic process was detected. Likewise, conditioned medium produced damage to the corneal cells that was proportional to the time of incubation, but this cytophatic effect involved only the most superficial layer of the human cornea and was not enough to explain amoebic invasion of Bowman s membrane. As a result of our observations, we suggest that the mechanical action of the trophozoites and phagocytosis of corneal cells during the process of corneal invasion are more important than previously suggested.

  16. Posterior polymorphous dystrophy of the cornea. An ultrastructural study.

    Science.gov (United States)

    de Felice, G P; Braidotti, P; Viale, G; Bergamini, F; Vinciguerra, P

    1985-01-01

    A corneal button excised from a 2-month-old infant with congenital posterior polymorphous dystrophy of the cornea, a rare disease affecting Descemet's membrane and endothelium, was examined by electron microscopy. We observed irregularly arranged, sometimes multilayered cells with marked epithelial features, lining the posterior surface of the cornea in place of the endothelium, and Descemet's membrane with focal alterations sometimes involving all of its layers. We interpreted these abnormal cells as epithelial-like cells. As these findings were in a very young patient, which is unusual, we concluded that the onset of the disease may take place in the early period of intrauterine life, corresponding to the beginning of Descemet's membrane production.

  17. Live imaging of newly formed lymphatic vessels in the cornea

    Institute of Scientific and Technical Information of China (English)

    Don Yuen; Xiufeng Wu; Alex C Kwan; Jeffrey LeDue; Hui Zhang; Tatiana Ecoiffier; Bronislaw Pytowski; Lu Chen

    2011-01-01

    Dear Editor,Lymphatic research denotes a field of new discovery and has experienced exponential growth in recent years [1-3].Though lymphatic dysfunction has been found in a broad spectrum of disorders from transplant rejection to cancer metastasis,to date,there is still little effective treatment for lymphatic diseases,so it is a field with urgent demand for new experimental approaches and therapeutic protocols.The cornea provides an ideal site for lymphatic research due to its accessible location,transparent nature,and alymphatic status under normal condition [2,4].Indeed,the use of this tissue for tumor angiogenesis research dates back to 1970s [5].Most recently,we have demonstrated that the cornea possesses a full range of plasticity in lymphatic formation and regression [6].An advanced technology for live imaging of lymphatic vessels in this tissue would therefore have widespread applications in biomedical research.

  18. Why does the healthy cornea resist Pseudomonas aeruginosa infection?

    Science.gov (United States)

    Evans, David J; Fleiszig, Suzanne M J

    2013-06-01

    To provide our perspective on why the cornea is resistant to infection based on our research results with Pseudomonas (P) aeruginosa. We focus on our current understanding of the interplay between bacteria, tear fluid, and the corneal epithelium that determines health as the usual outcome, and propose a theoretical model for how contact lens wear might change those interactions to enable susceptibility to P aeruginosa infection. Use of "null-infection" in vivo models, cultured human corneal epithelial cells, contact lens-wearing animal models, and bacterial genetics help to elucidate mechanisms by which P aeruginosa survives at the ocular surface, adheres, and traverses multilayered corneal epithelia. These models also help elucidate the molecular mechanisms of corneal epithelial innate defense. Tear fluid and the corneal epithelium combine to make a formidable defense against P aeruginosa infection of the cornea. Part of that defense involves the expression of antimicrobials such as β-defensins, the cathelicidin LL-37, cytokeratin-derived antimicrobial peptides, and RNase7. Immunomodulators such as SP-D and ST2 also contribute. Innate defenses of the cornea depend in part on MyD88, a key adaptor protein of TLR and IL-1R signaling, but the basal lamina represents the final barrier to bacterial penetration. Overcoming these defenses involves P aeruginosa adaptation, expression of the type III secretion system, proteases, and P aeruginosa biofilm formation on contact lenses. After more than 2 decades of research focused on understanding how contact lens wear predisposes to P aeruginosa infection, our working hypothesis places blame for microbial keratitis on bacterial adaptation to ocular surface defenses, combined with changes to the biochemistry of the corneal surface caused by trapping bacteria and tear fluid against the cornea under the lens. Copyright © 2013 Elsevier Inc. All rights reserved.

  19. Neuronal Changes in the Diabetic Cornea: Perspectives for Neuroprotection

    Science.gov (United States)

    Yamamoto, Shuichi

    2016-01-01

    Diabetic neuropathy is associated with neurotrophic ulcerations of the skin and cornea. Decreased corneal sensitivity and impaired innervation lead to weakened epithelial wound healing predisposing patients to ocular complications such as corneal infections, stromal opacification, and surface irregularity. This review presents recent findings on impaired corneal innervation in diabetic individuals, and the findings suggest that corneal neuropathy might be an early indicator of diabetic neuropathy. Additionally, the recent findings for neuroprotective and regenerative therapy for diabetic keratopathy are presented. PMID:28044131

  20. Management of chemical burns of the canine cornea

    OpenAIRE

    Christmas, Richard

    1991-01-01

    Significant clinical signs and general principles of treatment for chemical burns of the canine cornea are presented using three typical case studies for illustration. Alkali burns are more common in dogs than acid burns. The sources of alkali in this study were soap, cement, and mortar dust. Common signs of chemical burns are ocular pain, corneal ulceration, tear film inadequacy, corneal edema, and marked corneal neovascularity. Successful treatment requires thorough ocular lavage, treatment...

  1. [Temporary biokeratoprostheses in total destruction of the cornea].

    Science.gov (United States)

    Onishchenko, A L; Kolbasko, A V; Kramer, E R

    2016-01-01

    The paper presents an original method for temporary biokeratoprothetics in total destruction of the cornea, which consists of the following. In the operating room a 12-mm disc is cut out of patient's conchal cartilage by a trephine and then thinned down to 1 mm with a blade. The prepared autograft is placed in front of the iris completely overlapping corneal defect and sutured to the sclera with 10--12 U-shaped interrupted stitches using a 7/0 suture. Between the stitches 0.2--0.3 ml of viscoelastic are injected into the anterior chamber. Temporary blepharorrhaphy is done within the temporal one-third of the eyelids with a U-shaped suture 6/0. The authors present an own clinical observation of patient D., aged 46, with purulent corneal ulcer and total destruction of the cornea. In ophthalmic emergency, if no donor cornea is available, the described method allows to save the eyeball from its anatomical and functional loss. Further routine keratoplasty or optical keratoprosthetics may bring some functional improvement.

  2. Ultrahigh-resolution OCT imaging of the human cornea

    Science.gov (United States)

    Werkmeister, René M.; Sapeta, Sabina; Schmidl, Doreen; Garhöfer, Gerhard; Schmidinger, Gerald; Aranha dos Santos, Valentin; Aschinger, Gerold C.; Baumgartner, Isabella; Pircher, Niklas; Schwarzhans, Florian; Pantalon, Anca; Dua, Harminder; Schmetterer, Leopold

    2017-01-01

    We present imaging of corneal pathologies using optical coherence tomography (OCT) with high resolution. To this end, an ultrahigh-resolution spectral domain OCT (UHR-OCT) system based on a broad bandwidth Ti:sapphire laser is employed. With a central wavelength of 800 nm, the imaging device allows to acquire OCT data at the central, paracentral and peripheral cornea as well as the limbal region with 1.2 µm x 20 µm (axial x lateral) resolution at a rate of 140 000 A-scans/s. Structures of the anterior segment of the eye, not accessible with commercial OCT systems, are visualized. These include corneal nerves, limbal palisades of Vogt as well as several corneal pathologies. Cases such as keratoconus and Fuchs’s endothelial dystrophy as well as infectious changes caused by diseases like Acanthamoeba keratitis and scarring after herpetic keratitis are presented. We also demonstrate the applicability of our system to visualize epithelial erosion and intracorneal foreign body after corneal trauma as well as chemical burns. Finally, results after Descemet’s membrane endothelial keratoplasty (DMEK) are imaged. These clinical cases show the potential of UHR-OCT to help in clinical decision-making and follow-up. Our results and experience indicate that UHR-OCT of the cornea is a promising technique for the use in clinical practice, but can also help to gain novel insight in the physiology and pathophysiology of the human cornea. PMID:28271013

  3. Effects of genipin corneal crosslinking in rabbit corneas.

    Science.gov (United States)

    Avila, Marcel Y; Narvaez, Mauricio; Castañeda, Juan P

    2016-07-01

    To evaluate the effect of genipin, a natural crosslinking agent, in rabbit eyes. Department of Ophthalmology, Universidad Nacional de Colombia Centro de Tecnologia Oftalmica, Bogotá, Colombia. Experimental study. Ex vivo rabbit eyes (16; 8 rabbits) were treated with genipin 1.00%, 0.50%, and 0.25% for 5 minutes with a vacuum device to increase corneal permeability. Penetration was evaluated using Scheimpflug pachymetry (Pentacam). In the in vivo model (20 rabbits; 1 eye treated, 1 eye with vehicle), corneas were crosslinked with genipin as described. Corneal curvature, corneal pachymetry, and intraocular pressure (IOP) assessments as well as slitlamp examinations were performed 0, 7, 30, and 60 days after treatment. In the ex vivo model, Scheimpflug pachymetry showed deep penetration in the rabbit corneas with an increase in corneal density and a dose-dependent relationship. Corneal flattening was observed in treated eyes (mean 4.4 diopters ± 0.5 [SD]) compared with the control eyes. Pachymetry and IOP were stable in all evaluations. No eye showed toxicity in the anterior chamber or in the lens. Corneal crosslinking induced by genipin produced significant flattening of the cornea with no toxicity in rabbit eyes. This crosslinking could be useful in the treatment of corneal ectasia and in the modification of corneal curvature. None of the authors has a financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  4. Evaluation of corneal cell growth on tissue engineering materials as artificial cornea scaffolds

    Directory of Open Access Journals (Sweden)

    Hai-Yan Wang

    2013-12-01

    Full Text Available The keratoprosthesis (KPro; artificial cornea is a special refractive device to replace human cornea by using heterogeneous forming materials for the implantation into the damaged eyes in order to obtain a certain vision. The main problems of artificial cornea are the biocompatibility and stability of the tissue particularly in penetrating keratoplasty. The current studies of tissue-engineered scaffold materials through comprising composites of natural and synthetic biopolymers together have developed a new way to artificial cornea. Although a wide agreement that the long-term stability of these devices would be greatly improved by the presence of cornea cells, modification of keratoprosthesis to support cornea cells remains elusive. Most of the studies on corneal substrate materials and surface modification of composites have tried to improve the growth and biocompatibility of cornea cells which can not only reduce the stimulus of heterogeneous materials, but also more importantly continuous and stable cornea cells can prevent the destruction of collagenase. The necrosis of stroma and spontaneous extrusion of the device, allow for maintenance of a precorneal tear layer, and play the role of ensuring a good optical surface and resisting bacterial infection. As a result, improvement in corneal cells has been the main aim of several recent investigations; some effort has focused on biomaterial for its well biological properties such as promoting the growth of cornea cells. The purpose of this review is to summary the growth status of the corneal cells after the implantation of several artificial corneas.

  5. Proteinases of the cornea and preocular tear film.

    Science.gov (United States)

    Ollivier, F J; Gilger, B C; Barrie, K P; Kallberg, M E; Plummer, C E; O'Reilly, S; Gelatt, K N; Brooks, D E

    2007-01-01

    Maintenance and repair of corneal stromal extracellular matrix (ECM) requires a tightly coordinated balance of ECM synthesis, degradation and remodeling in which proteolytic enzymes (proteinases) perform important functions. There are natural proteinase inhibitors present in preocular tear film (PTF) and cornea simultaneously with proteinases that prevent excessive degradation of normal healthy tissue. Disorders occur when there is an imbalance between proteinases and proteinase inhibitors in favor of the proteinases, causing pathologic degradation of stromal collagen and proteoglycans in the cornea. Two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, are of major importance in terms of remodeling and degradation of the corneal stromal collagen. Immunohistochemical studies have shown different origins of MMP-2 and -9. MMP-2 is synthesized by corneal keratocytes and performs a surveillance function in the normal cornea, becoming locally activated to degrade collagen molecules that occasionally become damaged. Alternatively, MMP-9 may be produced by epithelial cells and polymorphonuclear neutrophils following corneal wounding. Because the cornea is in close contact with the preocular tear film (PTF), proteinases have been evaluated in the PTF. In damaged corneas, total proteolytic activity in the tear fluid was found to be significantly increased compared to normal eyes and contralateral eyes. Studies analyzing the proteolytic activity in serial PTF samples during corneal healing led to the following conclusions: ulcerative keratitis in animals is associated with initially high levels of tear film proteolytic activity, which decrease as ulcers heal; proteinase levels in melting ulcers remain elevated leading to rapid progression of the ulcers. The success of medical and surgical treatment of the corneal ulcers is reflected by the proteolytic activity in tears. In animals, successful treatment leads to a rapid reduction in tear film proteolytic activity that

  6. The Ets transcription factor EHF as a regulator of cornea epithelial cell identity.

    Science.gov (United States)

    Stephens, Denise N; Klein, Rachel Herndon; Salmans, Michael L; Gordon, William; Ho, Hsiang; Andersen, Bogi

    2013-11-29

    The cornea is the clear, outermost portion of the eye composed of three layers: an epithelium that provides a protective barrier while allowing transmission of light into the eye, a collagen-rich stroma, and an endothelium monolayer. How cornea development and aging is controlled is poorly understood. Here we characterize the mouse cornea transcriptome from early embryogenesis through aging and compare it with transcriptomes of other epithelial tissues, identifying cornea-enriched genes, pathways, and transcriptional regulators. Additionally, we profiled cornea epithelium and stroma, defining genes enriched in these layers. Over 10,000 genes are differentially regulated in the mouse cornea across the time course, showing dynamic expression during development and modest expression changes in fewer genes during aging. A striking transition time point for gene expression between postnatal days 14 and 28 corresponds with completion of cornea development at the transcriptional level. Clustering classifies co-expressed, and potentially co-regulated, genes into biologically informative categories, including groups that exhibit epithelial or stromal enriched expression. Based on these findings, and through loss of function studies and ChIP-seq, we show that the Ets transcription factor EHF promotes cornea epithelial fate through complementary gene activating and repressing activities. Furthermore, we identify potential interactions between EHF, KLF4, and KLF5 in promoting cornea epithelial differentiation. These data provide insights into the mechanisms underlying epithelial development and aging, identifying EHF as a regulator of cornea epithelial identity and pointing to interactions between Ets and KLF factors in promoting epithelial fate. Furthermore, this comprehensive gene expression data set for the cornea is a powerful tool for discovery of novel cornea regulators and pathways.

  7. Expression of glutathione transferases in corneal cell lines, corneal tissues and a human cornea construct.

    Science.gov (United States)

    Kölln, Christian; Reichl, Stephan

    2016-06-15

    Glutathione transferase (GST) expression and activity were examined in a three-dimensional human cornea construct and were compared to those of excised animal corneas. The objective of this study was to characterize phase II enzyme expression in the cornea construct with respect to its utility as an alternative to animal cornea models. The expression of the GSTO1-1 and GSTP1-1 enzymes was investigated using immunofluorescence staining and western blotting. The level of total glutathione transferase activity was determined using 1-chloro-2,4- dinitrobenzene as the substrate. Furthermore, the levels of GSTO1-1 and GSTP1-1 activity were examined using S-(4-nitrophenacyl)glutathione and ethacrynic acid, respectively, as the specific substrates. The expression and activity levels of these enzymes were examined in the epithelium, stroma and endothelium, the three main cellular layers of the cornea. In summary, the investigated enzymes were detected at both the protein and functional levels in the cornea construct and the excised animal corneas. However, the enzymatic activity levels of the human cornea construct were lower than those of the animal corneas.

  8. Delivery of antisense oligonucleotide to the cornea by iontophoresis.

    Science.gov (United States)

    Berdugo, M; Valamanesh, F; Andrieu, C; Klein, C; Benezra, D; Courtois, Y; Behar-Cohen, F

    2003-04-01

    We wished to evaluate the potential of iontophoresis to promote the delivery of antisense oligonucleotides (ODN) directed at the vascular endothelial growth factor (VEGF)-R2 receptor (KDR/Flk) to the cornea of the rat eye. Fluorescence (CY5)-labeled ODNs in phosphate-buffered saline (PBS) (20 microM) were locally administered to rat eyes, and their fate within the anterior segment was studied. Thirty-four male, 5-week-old Wistar rats were used for all experiments. The rats were divided in four groups. In group I (12 rats, 12 eyes), the ODNs (20 microM) were delivered by iontophoresis (300 microA for 5 minutes) using a specially designed corneal applicator. In group II (12 rats, 12 eyes), the ODNs (20 microM) were delivered using the same applicator, but no electrical current was applied. In group III (6 rats, 6 eyes), a corneal neovascular reaction was induced prior to the application of ODNs (20 microM), and iontophoresis electrical current was delivered as for group I rats. Group IV (4 rats, 4 eyes) received ODN (60 microM) iontophoresis application (300 microA for 5 minutes) and were used for ODN integrity studies. The animals were killed 5 minutes, 90 minutes, and 24 hours after a single ODN application and studied. Topically applied ODNs using the same iontophoresis applicator but without current do not penetrate the cornea and remain confined to the superficial epithelial layer. ODNs delivered with transcorneoscleral iontophoresis penetrate into all corneal layers and are also detected in the iris. In corneas with neovascularization, ODNs were particularly localized within the vascular endothelial cells of the stroma. ODNs extracted from eye tissues 24 hours after iontophoresis remained unaltered. The iontophoresis current did not cause any detectable ocular damage under these conditions. Iontophoresis promotes the delivery of ODNs to the anterior segment of the eye, including all corneal layers. Iontophoresis of ODNs directed at VEGF-R2 may be used for the

  9. An adaptive algorithm for the cornea modeling from keratometric data

    CERN Document Server

    Martinez-Finkelshtein, Andrei; Castro-Luna, Gracia M; Alio, Jorge L

    2010-01-01

    In this paper we describe an adaptive and multi-scale algorithm for the parsimonious fit of the corneal surface data that allows to adapt the number of functions used in the reconstruction to the conditions of each cornea. The method implements also a dynamical selection of the parameters and the management of noise. It can be used for the real-time reconstruction of both altimetric data and corneal power maps from the data collected by keratoscopes, such as the Placido rings based topographers, decisive for an early detection of corneal diseases such as keratoconus. Numerical experiments show that the algorithm exhibits a steady exponential error decay, independently of the level of aberration of the cornea. The complexity of each anisotropic gaussian basis functions in the functional representation is the same, but their parameters vary to fit the current scale. This scale is determined only by the residual errors and not by the number of the iteration. Finally, the position and clustering of their centers,...

  10. Wide-angle cornea-sclera (OCULAR) topography

    Science.gov (United States)

    Klein, Stanley A.; Corzine, John; Corbin, Jacob A.; Wechsler, Sheldon; Carney, Thom

    2002-06-01

    Most corneal topographers are slope-based instruments, measuring corneal slope based on light reflected by the cornea acting as a mirror. This mirror method limits corneal coverage to about 9 mm diameter. Both refractive surgery and contact lens fitting actually require a larger coverage than is obtainable using slope-based instruments. Height-based instruments should be able to measure a cornea/sclera area that is twice the size (four times the area) of slope-based topographers with an accuracy of a few microns. We have been testing a prototype of a new model height-based topographer manufactured by Euclid Systems. We find that single shots can produce a corneal coverage of up to 16 mm vertical and 20 mm horizontal. The heights and slopes in the corneal region have good replicability. Although the scleral region is noisier, it is the only topographer available able to measure scleral topography that is critically important to contact lens fitting. There are a number of improvements to the Euclid software and hardware that would enable it to fill an important niche in eye care and eye research.

  11. Efficient numerical modeling of the cornea, and applications

    Science.gov (United States)

    Gonzalez, L.; Navarro, Rafael M.; Hdez-Matamoros, J. L.

    2004-10-01

    Corneal topography has shown to be an essential tool in the ophthalmology clinic both in diagnosis and custom treatments (refractive surgery, keratoplastia), having also a strong potential in optometry. The post processing and analysis of corneal elevation, or local curvature data, is a necessary step to refine the data and also to extract relevant information for the clinician. In this context a parametric cornea model is proposed consisting of a surface described mathematically by two terms: one general ellipsoid corresponding to a regular base surface, expressed by a general quadric term located at an arbitrary position and free orientation in 3D space and a second term, described by a Zernike polynomial expansion, which accounts for irregularities and departures from the basic geometry. The model has been validated obtaining better adjustment of experimental data than other previous models. Among other potential applications, here we present the determination of the optical axis of the cornea by transforming the general quadric to its canonical form. This has permitted us to perform 3D registration of corneal topographical maps to improve the signal-to-noise ratio. Other basic and clinical applications are also explored.

  12. Morphology, topography, and optics of the orthokeratology cornea

    Science.gov (United States)

    Faria-Ribeiro, Miguel; Belsue, Rafael Navarro; López-Gil, Norberto; González-Méijome, José Manuel

    2016-07-01

    The goal of this work was to objectively characterize the external morphology, topography, and optics of the cornea after orthokeratology (ortho-k). A number of 24 patients between the ages of 17 and 30 years (median=24 years) were fitted with Corneal Refractive Therapy® contact lenses to correct myopia between -2.00 and -5.00 diopters (D) (median=-3.41 D). A classification algorithm was applied to conduct an automatic segmentation based on the mean local curvature. As a result, three zones (optical zone, transition zone, and peripheral zone) were delimited. Topographical analysis was provided through global and zonal fit to a general ellipsoid. Ray trace on partially customized eye models provided wave aberrations and retinal image quality. Monozone topographic description of the ortho-k cornea loses accuracy when compared with zonal description. Primary (C40) and secondary (C60) spherical aberration (SA) coefficients for a 5-mm pupil increased 3.68 and 19 times, respectively, after the treatments. The OZ area showed a strong correlation with C40 (r=-0.49, p<0.05) and a very strong correlation with C60 (r=0.78, p<0.01). The OZ, as well as the TZ, areas did not correlate with baseline refraction. The increase in the eye's positive SA after ortho-k is the major factor responsible for the decreased retinal optical quality of the unaccommodated eye.

  13. Molecular cloning of a new angiopoietinlike factor from the human cornea

    NARCIS (Netherlands)

    Peek, R; van Gelderen, BE; Bruinenberg, M; Kijlstra, A

    PURPOSE. To isolate tissue-specific gene products that contribute to corneal integrity. METHODS. A cDNA library was constructed and differentially hybridized. Cornea-specific clones were purified and further characterized. RESULTS. In this study cornea-specific gene products were isolated by

  14. Multiphoton Imaging of Rabbit Cornea Treated with Mitomycin C after Photorefractive Keratectomy

    Science.gov (United States)

    Hsueh, Chiu-Mei; Lo, Wen; Wang, Tsung-Jen; Hu, Fung-Rong; Dong, Chen-Yuan

    2007-07-01

    In this work we use multiphoton microscopy to observe the post surgery structure variation of rabbit cornea after photorefractive keratectomy (PRK). In addition, we added mitomycin C (MMC) to the post surgery rabbit cornea in order to investigate the effect of MMC treatment on the postoperative regeneration.

  15. Xanthelasmata, arcus corneae, and ischaemic vascular disease and death in general population: prospective cohort study

    DEFF Research Database (Denmark)

    Christoffersen, Mette; Frikke-Schmidt, Ruth; Schnohr, Peter

    2011-01-01

    To test the hypothesis that xanthelasmata and arcus corneae, individually and combined, predict risk of ischaemic vascular disease and death in the general population.......To test the hypothesis that xanthelasmata and arcus corneae, individually and combined, predict risk of ischaemic vascular disease and death in the general population....

  16. Comparison of confocal microscopy and two-photon microscopy in mouse cornea in vivo.

    Science.gov (United States)

    Lee, Jun Ho; Lee, Seunghun; Gho, Yong Song; Song, In Seok; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2015-03-01

    High-resolution imaging of the cornea is important for studying corneal diseases at cellular levels. Confocal microscopy (CM) has been widely used in the clinic, and two-photon microscopy (TPM) has recently been introduced in various pre-clinical studies. We compared the performance of CM and TPM in normal mouse corneas and neovascularized mouse corneas induced by suturing. Balb/C mice and C57BL/6 mice expressing green fluorescent protein (GFP) were used to compare modalities based on intrinsic contrast and extrinsic fluorescence contrast. CM based on reflection (CMR), CM based on fluorescence (CMF), and TPM based on intrinsic/extrinsic fluorescence and second harmonic generation (SHG) were compared by imaging the same sections of mouse corneas sequentially in vivo. In normal mouse corneas, CMR visualized corneal cell morphologies with some background noise, and CMF visualized GFP expressing corneal cells clearly. TPM visualized corneal cells and collagen in the stroma based on fluorescence and SHG, respectively. However, in neovascularized mouse corneas, CMR could not resolve cells deep inside the cornea due to high background noise from the effects of increased structural irregularity induced by suturing. CMF and TPM visualized cells and induced vasculature better than CMR because both collect signals from fluorescent cells only. Both CMF and TPM had signal decays with depth due to the structural irregularity, with CMF having faster signal decay than TPM. CMR, CMF, and TPM showed different degrees of image degradation in neovascularized mouse corneas.

  17. Prevalence and clinical consequences of herpes simplex virus type 1 DNA in human cornea tissues

    NARCIS (Netherlands)

    L. Remeijer (Lies); R. Duan (Rui); J.M. van Dun (Jessica); M.A.W. Bettink; A.D.M.E. Osterhaus (Albert); G.M.G.M. Verjans (George)

    2009-01-01

    textabstractBackground. We determined the prevalence and clinical consequences of herpes simplex virus (HSV) type 1 (HSV-1), HSV type 2 (HSV-2), and varicella-zoster virus (VZV) in cornea tissues obtained after penetrating keratoplasty (PKP) was performed. Methods. The excised corneas of 83 patients

  18. Prevalence and clinical consequences of herpes simplex virus type 1 DNA in human cornea tissues

    NARCIS (Netherlands)

    L. Remeijer (Lies); R. Duan (Rui); J.M. van Dun (Jessica); M.A.W. Bettink; A.D.M.E. Osterhaus (Ab); G.M.G.M. Verjans (George)

    2009-01-01

    textabstractBackground. We determined the prevalence and clinical consequences of herpes simplex virus (HSV) type 1 (HSV-1), HSV type 2 (HSV-2), and varicella-zoster virus (VZV) in cornea tissues obtained after penetrating keratoplasty (PKP) was performed. Methods. The excised corneas of 83 patients

  19. Tissue Engineering the Cornea: The Evolution of RAFT.

    Science.gov (United States)

    Levis, Hannah J; Kureshi, Alvena K; Massie, Isobel; Morgan, Louise; Vernon, Amanda J; Daniels, Julie T

    2015-01-22

    Corneal blindness affects over 10 million people worldwide and current treatment strategies often involve replacement of the defective layer with healthy tissue. Due to a worldwide donor cornea shortage and the absence of suitable biological scaffolds, recent research has focused on the development of tissue engineering techniques to create alternative therapies. This review will detail how we have refined the simple engineering technique of plastic compression of collagen to a process we now call Real Architecture for 3D Tissues (RAFT). The RAFT production process has been standardised, and steps have been taken to consider Good Manufacturing Practice compliance. The evolution of this process has allowed us to create biomimetic epithelial and endothelial tissue equivalents suitable for transplantation and ideal for studying cell-cell interactions in vitro.

  20. Tissue Engineering the Cornea: The Evolution of RAFT

    Directory of Open Access Journals (Sweden)

    Hannah J. Levis

    2015-01-01

    Full Text Available Corneal blindness affects over 10 million people worldwide and current treatment strategies often involve replacement of the defective layer with healthy tissue. Due to a worldwide donor cornea shortage and the absence of suitable biological scaffolds, recent research has focused on the development of tissue engineering techniques to create alternative therapies. This review will detail how we have refined the simple engineering technique of plastic compression of collagen to a process we now call Real Architecture for 3D Tissues (RAFT. The RAFT production process has been standardised, and steps have been taken to consider Good Manufacturing Practice compliance. The evolution of this process has allowed us to create biomimetic epithelial and endothelial tissue equivalents suitable for transplantation and ideal for studying cell-cell interactions in vitro.

  1. Epithelial ion transport in rabbit corneas following myopic keratomileusis.

    Science.gov (United States)

    Swinger, C A; Candia, O A; Marcus, S; Barker, B A; Kornmehl, E W

    1986-08-01

    In isolated rabbit corneas that had undergone lamellar keratectomy or myopic keratomileusis, the stimulation of chloride transport by 10(-5) M epinephrine was completely inhibited at 1 week following surgery. At 28 days following surgery, both groups responded to 10(-7) M epinephrine. The response to 10(-5) M amphotericin B was normal both at 1 week and at 28 days following surgery. We conclude that, although the Na-K pump was not affected by the lamellar keratectomy and cryolathing, that either the epithelial beta receptors and/or the cAMP pathway were temporarily inhibited for at least 1 week following surgery. A lamellar keratectomy, therefore, can have an adverse effect on the epithelial transport system of the corneal epithelium even though the epithelium may appear normal clinically.

  2. Polymicrobial Infection of the Cornea Due to Contact Lens Wear

    Science.gov (United States)

    Sızmaz, Selçuk; Bingöllü, Sibel; Erdem, Elif; Kibar, Filiz; Koltaş, Soner; Yağmur, Meltem; Ersöz, Reha

    2016-01-01

    A 38-year-old male presented with pain and redness in his left eye. He had a history of wearing contact lenses. His ophthalmic examination revealed a large corneal ulcer with surrounding infiltrate. Cultures were isolated from the contact lenses, lens solutions, storage cases, and conjunctivae of both eyes and also corneal scrapings of the left eye. Fortified vancomycin and amikacin drops were started hourly. Culture results of conjunctivae of each eye and left cornea were positive for Pseudomonas aeruginosa; cultures from the contact lenses, lens solution and storage case of both eyes revealed Pseudomonas aeruginosa and Alcaligenes xylosoxidans. Polymerase chain reaction of the corneal scraping was positive for Acanthameoba. The topical antibiotics were changed with ones that both bacteria were sensitive to and anti-amoebic therapy was added. The patient had two recurrences following initial presentation despite intensive therapy. Keratitis occurred due to multiple pathogens; the relapsing course despite adequate therapy is potentially associated with this polymicrobial etiology. PMID:27800266

  3. The effects of oral and topical corticosteroid in rabbit corneas.

    Science.gov (United States)

    Araki-Sasaki, Kaoru; Katsuta, Osamu; Mano, Hidetoshi; Nagano, Takashi; Nakamura, Masatsugu

    2016-09-05

    To determine the most effective route of administration of corticosteroids in the treatment of ocular surface disease, by characterizing the difference between oral prednisolone and topical dexamethasone administration using an animal model. Pharmacokinetic analyses determined the corticosteroid concentrations in the normal ocular tissues of rabbits after oral or topical administration of corticosteroids using LC-MS/MS. In wound healing analyses, the area of the epithelial defect created by keratectomy using a 6-mm trephine was calculated with an image analyzer using an orally or topically steroid-administrated animal model. The average size of basal epithelial cells, the frequency of mitotic basal epithelial cells, the number of squamous cells, and the number of hypertrophic stromal fibroblasts were determined in the enucleated corneal tissues after wound closure. By slit lamp examination, no remarkable differences were observed between orally and topically administered groups. Pharmacokinetic analyses showed that the distribution of dexamethasone after topical administration was superior to that after oral administration in the cornea. In contrast, both concentrations of corticosteroid applied topically and orally were similar with regards to AUCs (area under the concentration-time curve) in the conjunctiva. Although the healing rate was slower in the topical group, all corneas were almost healed within 96 h in the wound healing analysis. According to the histological analyses of epithelial cells, the average basal cell size was larger, the frequency of mitotic basal cells was greater, and the number of squamous epithelial cell layers was lower in the topically administered group although all of these differences were with no statistical significance. However, the number of hypertrophic stromal fibroblasts in the topically administered group was significantly lower than that in the orally administered group. There are different distributions and effects between

  4. Xanthelasma palpebrarum with arcus cornea: A clinical and biochemical study

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    Pragya Ashok Nair

    2016-01-01

    Full Text Available Background: Xanthelasma palpebrarum (XP is characterized by sharply demarcated yellowish flat plaques on upper and lower eyelids. It is commonly seen in women with a peak incidence at 30–50 years. It is also considered as the cutaneous marker of underlying atherosclerosis along with the disturbed lipid metabolism. XP and corneal arcus are associated with increased levels of serum cholesterol and low-density lipoprotein (LDL cholesterol. Aims and Objectives: To study the clinical pattern of XP, its relationship with lipid profile and association with arcus cornea. Materials and Methods: This study was conducted at Department of Dermatology and Opthalmology, between August 2013 and January 2015. Patients with clinical diagnosis of XP who visited skin outpatient department and willing to undergo lipid profile test and eye examination were included in the study. Data regarding demographics, clinical findings, family history, and past history were noted along with the lipid profile details. Data of age-matched healthy controls were taken for comparison. The clinical profile of the participants was presented using frequency and proportions. Gender wise analysis comparing the lipid profile in cases with XP and without XP was done using independent sample t-test. Results: Total 49 patients of XP, 81.6% were females. Maximum, 35% patients were among 50–60 years of age and 69.4% were homemakers by occupation. The average lipid values were-cholesterol 210.57 mg%, triglyceride 123.06 mg%. LDL 142.79 mg% and VLDL 30.95 mg% among patients of XP. Arcus cornea was found in 20% cases of XP. Conclusions: Patients of XP requires proper investigation at the onset and regular follow-up thereafter for any altered lipid profile and early diagnosis of coronary artery disease.

  5. Effects of the holmium laser on the human cornea: a preliminary study

    Science.gov (United States)

    Mueller, Linda J.; Tassignon, Marie J.; Trau, Rene; Pels, Liesbeth; Vrensen, Gijs F.

    1996-12-01

    Treatment of peripheral post-mortem human corneas with the Holmium laser in a ring pattern resulted in opaque spots. One pair of treated eyes was immediately processed for light and electron microscopy and three other treated eyes were preserved for 4 days in medium in order to compare direct and short-term effects of the Holmium laser. Cross as well as frontal light microscopical sections of all eyes revealed interconnecting bands between the spots. At the ultrastructural level the anterior corneal tissue within these spots was characterized by coagulation of cells and collagen and shoed either a dramatic distorting effect on the epithelium in the eyes processed immediately or a single layer of flattened multi-nucleolated epithelial cells having more than one nucleolus per nucleus in the eyes stored in medium. Furthermore, the spots showed disturbed Bowman's layer, destroyed keratocytes and collagen fibrils which were either coagulated or organized chaotically. The interconnecting bands contained alternating normal and coagulated collagen fibers. The rest of the cornea outside the spots had a normal appearance. In corneas stored in medium, both keratocytes and epithelial cells over the entire cornea exhibited accumulations of cytoplasmic fibrils and glycogen particles. These phenomena were not observed in non-preserved corneas, suggesting that the differences are due to preservation and not due to the laser treatment. It is concluded that morphological changes occur mainly in the treated peripheral cornea whereas the central untreated cornea remains unaffected,indicating that the Holmium laser is a reliable instrument to treat hypermetropic patients.

  6. Preliminary study on the effect of stiffness on lamb wave propagation in bovine corneas.

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    Zhang, Xin-Yu; Yin, Yin; Guo, Yan-Rong; Diao, Xian-Fen; Chen, Xin

    2013-01-01

    The viscoelastic properties of human cornea could provide valuable information for various clinical applications. Particularly, it will be helpful to achieve a patient-specific biomechanical optimization in LASIK refractive surgery, early detection of corneal ecstatic disease or improved accuracy of intraocular pressure (IOP) measurement. However, there are few techniques that are capable of accurately assessing the corneal elasticity in situ in a nondestructive fashion. In order to develop a quantitative method for assessing both elasticity and viscosity of the cornea, we use ultrasound radiation force to excite Lamb waves in cornea, and a pulse echo transducer to track the tissue vibration. The fresh postmortem bovine eyes were treated via collagen cross-linking to make the cornea stiff. The effect of stiffness was studied by comparing the propagation of Lamb waves in normal and treated corneas. It was found that the waveform of generated Lamb waves changed significantly due to the increase in higher modes in treated corneas. This result indicated that the generated waveform was a complex of multiple harmonics and the varied stiffness will affect the energy distribution over different components. Therefore, it is important for assessing the viscoelastic properties of the cornea to know the components of Lamb wave and calculate the phase velocity appropriately.

  7. Development and characterization of a full-thickness acellular porcine cornea matrix for tissue engineering.

    Science.gov (United States)

    Du, Liqun; Wu, Xinyi

    2011-07-01

    Our aim was to produce a natural, acellular matrix from porcine cornea for use as a scaffold in developing a tissue-engineered cornea replacement. Full-thickness, intact porcine corneas were decellularized by immersion in 0.5% (wt/vol) sodium dodecyl sulfate. The resulting acellular matrices were then characterized and examined specifically for completeness of the decellularization process. Histological analyses of decellularized corneal stromas showed that complete cell and α-Gal removal was achieved, while the major structural proteins including collagen type I and IV, laminin, and fibronectin were retained. DAPI staining did not detect any residual DNA within the matrix, and the DNA contents, which reflect the presence of cellular materials, were significantly diminished in the decellularized cornea. The collagen content of the decellularized cornea was well maintained compared with native tissues. Uniaxial tensile testing indicated that decellularization did not significantly compromise the ultimate tensile strength of the tissue (P > 0.05). In vitro cytotoxicity assays using rabbit corneal fibroblast cultures excluded the presence of soluble toxins in the biomaterial. In vivo implantation to rabbit interlamellar stromal pockets showed good biocompability. In summary, a full-thickness natural acellular matrix retaining the major structural components and strength of the cornea has been successfully developed. The matrix is biocompatible with cornea-derived cells and has potential for use in corneal transplantation and tissue-engineering applications. © 2011, Copyright the Authors. Artificial Organs © 2011, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  8. Cornea donors who have had prior refractive surgery: data from the Eye Bank Association of America.

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    Fargione, Robert A; Channa, Prabjot

    2016-07-01

    Millions of Americans have undergone refractive surgeries, including radial keratotomy, photorefractive keratectomy, and laser-assisted in situ keratomileusis. Eye Bank Association of America medical standards do not permit corneas from patients who have undergone refractive procedures to be used in penetrating keratoplasty, anterior lamellar keratoplasty, or tectonic grafting procedures. Such corneas, can, however, be used for endothelial corneal transplantation. The objective of this article is to provide an update on current trends for the screening and usage of corneas that have undergone refractive surgery. Several case reports have highlighted the difficulty in using postrefractive surgery corneas in penetrating keratoplasty. However, tissue with anterior stromal flaws, including a history of refractive surgery, has been used in endothelial keratoplasty with equivalent outcomes in topography, endothelial cell count, and visual acuity. Many modalities for proper identification of postmortem donor corneas that have undergone refractive surgery have been studied. Corneas with a history of refractive surgery have found use in endothelial keratoplasty. Multiple objective methods of tissue identification have been investigated to avoid the use of these corneas in penetrating or anterior keratoplasty surgeries.

  9. Imaging of Keratoconic and normal human cornea with a Brillouin imaging system (Conference Presentation)

    Science.gov (United States)

    Besner, Sebastien; Shao, Peng; Scarcelli, Giuliano; Pineda, Roberto; Yun, Seok-Hyun (Andy)

    2016-03-01

    Keratoconus is a degenerative disorder of the eye characterized by human cornea thinning and morphological change to a more conical shape. Current diagnosis of this disease relies on topographic imaging of the cornea. Early and differential diagnosis is difficult. In keratoconus, mechanical properties are found to be compromised. A clinically available invasive technique capable of measuring the mechanical properties of the cornea is of significant importance for understanding the mechanism of keratoconus development and improve detection and intervention in keratoconus. The capability of Brillouin imaging to detect local longitudinal modulus in human cornea has been demonstrated previously. We report our non-contact, non-invasive, clinically viable Brillouin imaging system engineered to evaluate mechanical properties human cornea in vivo. The system takes advantage of a highly dispersive 2-stage virtually imaged phased array (VIPA) to detect weak Brillouin scattering signal from biological samples. With a 1.5-mW light beam from a 780-nm single-wavelength laser source, the system is able to detect Brillouin frequency shift of a single point in human cornea less than 0.3 second, at a 5μm/30μm lateral/axial resolution. Sensitivity of the system was quantified to be ~ 10 MHz. A-scans at different sample locations on a human cornea with a motorized human interface. We imaged both normal and keratoconic human corneas with this system. Whereas no significantly difference were observed outside keratocnic cones compared with normal cornea, a highly statistically significantly decrease was found in the cone regions.

  10. A comparison of three methods of decellularization of pig corneas to reduce immunogenicity

    Institute of Scientific and Technical Information of China (English)

    Whayoung; Lee; Yuko; Miyagawa; Cassandra; Long; David; K.; C.; Cooper; Hidetaka; Hara

    2014-01-01

    ·AIM: To investigate whether decellularization using different techniques can reduce immunogenicity of the cornea, and to explore the decellularized cornea as a scaffold for cultured corneal endothelial cells(CECs).Transplantation of decellularized porcine corneas increases graft transparency and survival for longer periods compared with fresh grafts.·METHODS: Six-month-old wild-type pig corneas were cut into 100-200 μm thickness, and then decellularized by three different methods: 1) 0.1% sodium dodecyl sulfate(SDS); 2) hypoxic nitrogen(N2); and 3) hypertonic NaCl. Thickness and transparency were assessed visually. Fresh and decellularized corneas were stained with hematoxylin/eosin(H&E), and for the presence of galactose-α1,3-galactose(Gal) and N-glycolylneuraminic acid(NeuGc, a nonGal antigen). Also, a human IgM/IgG binding assay was performed. Cultured porcine CECs were seeded on the surface of the decellularized cornea and examined after H&E staining.· RESULTS: All three methods of decellularization reduced the number of keratocytes in the stromal tissue by >80% while the collagen structure remained preserved. No remaining nuclei stained positive for Gal or NeuGc, and expression of these oligosaccharides on collagen was also greatly decreased compared to expression on fresh corneas. Human IgM/IgG binding to decellularized corneal tissue was considerably reduced compared to fresh corneal tissue. The cultured CECs formed a confluent monolayer on the surface of decellularized tissue.· CONCLUSION: Though incomplete, the significant reduction in the cellular component of the decellularized cornea should be associated with a significantly reduced in vivo immune response compared to fresh corneas.

  11. An Immunohistochemical Study of Langerhans Cells,T-Cells and the HLA Antigen in Human Cornea

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    The distribution of Langerhans cells (LC),T-cell subsets andHLA antigen in 12 normal and 7 morbid corneas,including 4 of suppurativecorneal ulcer and 3 of uveogenic endophthalmitis,was investigated withmonoclonal antibodies.The results revealed that a small amount of LC andT-cell subsets were present in the limbal region of normal corneas,whilelarge numbers of LC and OKT_4~+ were observed in the corneas of suppurativeulcer.HLA-A,B,C antigens were expressed on the epithelial cells andkeratocytes of the n...

  12. Dual-path handheld system for cornea and retina imaging using optical coherence tomography

    Science.gov (United States)

    Shirazi, Muhammad Faizan; Wijesinghe, Ruchire Eranga; Ravichandran, Naresh Kumar; Kim, Pilun; Jeon, Mansik; Kim, Jeehyun

    2016-11-01

    A dual-path handheld system is proposed for cornea and retina imaging using spectral domain optical coherence tomography. The handheld sample arm is designed to acquire two images simultaneously. Both eyes of a person can be imaged at the same time to obtain the images of the cornea of one eye and the retina of the other eye. Cornea, retina, and optic disc images are acquired with the proposed sample arm. Experimental results demonstrate the usefulness of this system for imaging of different eye segments. This system reduces the time required for imaging of the two eyes and is cost effective.

  13. A time-delay calibrated method for cornea hysteresis and intraocular pressure measurement

    Science.gov (United States)

    Wang, Kuo-Jen; Tsai, Che-Liang; Wang, Wai; Hsu, Long; Hsu, Ken-Yuh

    2016-04-01

    The presence of cornea hysteresis (CH) in characterizing the intraocular pressure (IOP) of a human eye deteriorates the accuracy of IOP. To suppress CH, the pressure gauge of a tonometer must be located as close as possible to the cornea. However, this arrangement is unpractical because appropriate working distance to the cornea is required. In this paper, a time-delay calibrated (TDC) method is proposed to counteract the undesired effect of CH in characterizing the IOP. Employing this TDC method, the CH approaches to zero for most eyes measured.

  14. A role for smoothened during murine lens and cornea development.

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    Janet J Y Choi

    Full Text Available Various studies suggest that Hedgehog (Hh signalling plays roles in human and zebrafish ocular development. Recent studies (Kerr et al., Invest Ophthalmol Vis Sci. 2012; 53, 3316-30 showed that conditionally activating Hh signals promotes murine lens epithelial cell proliferation and disrupts fibre differentiation. In this study we examined the expression of the Hh pathway and the requirement for the Smoothened gene in murine lens development. Expression of Hh pathway components in developing lens was examined by RT-PCR, immunofluorescence and in situ hybridisation. The requirement of Smo in lens development was determined by conditional loss-of-function mutations, using LeCre and MLR10 Cre transgenic mice. The phenotype of mutant mice was examined by immunofluorescence for various markers of cell cycle, lens and cornea differentiation. Hh pathway components (Ptch1, Smo, Gli2, Gli3 were detected in lens epithelium from E12.5. Gli2 was particularly localised to mitotic nuclei and, at E13.5, Gli3 exhibited a shift from cytosol to nucleus, suggesting distinct roles for these transcription factors. Conditional deletion of Smo, from ∼E12.5 (MLR10 Cre did not affect ocular development, whereas deletion from ∼E9.5 (LeCre resulted in lens and corneal defects from E14.5. Mutant lenses were smaller and showed normal expression of p57Kip2, c-Maf, E-cadherin and Pax6, reduced expression of FoxE3 and Ptch1 and decreased nuclear Hes1. There was normal G1-S phase but decreased G2-M phase transition at E16.5 and epithelial cell death from E14.5-E16.5. Mutant corneas were thicker due to aberrant migration of Nrp2+ cells from the extraocular mesenchyme, resulting in delayed corneal endothelial but normal epithelial differentiation. These results indicate the Hh pathway is required during a discrete period (E9.5-E12.5 in lens development to regulate lens epithelial cell proliferation, survival and FoxE3 expression. Defective corneal development occurs

  15. Accelerating repaired basement membrane after bevacizumab treatment on alkali-burned mouse cornea

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    Koon-Ja Lee

    2013-04-01

    Full Text Available To understand the corneal regeneration induced by bevacizumab,we investigated the structure changes of stroma andbasement membrane regeneration. A Stick soaked in 0.5 NNaOH onto the mouse cornea and 2.5 mg/ml of bevacizumabwas delivered into an alkali-burned cornea (2 μl by subconjunctivalinjections at 1 hour and 4 days after injury. At 7 daysafter injury, basement membrane regeneration was observedby transmission electron microscope. Uneven and thin epithelialbasement membrane, light density of hemidesmosomes,and edematous collagen fibril bundles are shown in thealkali-burned cornea. Injured epithelial basement membraneand hemidesmosomes and edematous collagen fibril bundlesresulting from alkali-burned mouse cornea was repaired bybevacizumab treatment. This study demonstrates that bevacizumabcan play an important role in wound healing in thecornea by accelerating the reestablishment of basementmembrane integrity that leads to barriers for scar formation.[BMB Reports 2013; 46(4: 195-200

  16. Zinc oxide tetrapods inhibit herpes simplex virus infection of cultured corneas

    Science.gov (United States)

    Duggal, Neil; Jaishankar, Dinesh; Yadavalli, Tejabhiram; Hadigal, Satvik; Mishra, Yogendra Kumar; Adelung, Rainer

    2017-01-01

    Purpose Infection of the human cornea by herpes simplex virus type-1 (HSV-1) can cause significant vision loss. The purpose of this study was to develop an ex vivo model to visualize viral growth and spread in the cornea. The model was also used to analyze cytokine production and study the antiviral effects of zinc oxide tetrapods. Methods A β-galactosidase-expressing recombinant virus, HSV-1(KOS)tk12, was used to demonstrate the ability of the virus to enter and develop blue plaques on human corneal epithelial (HCE) cells and corneal tissues. Freshly obtained porcine corneas were cultured and then scratched before infection with HSV-1(KOS)tk12. The blue plaques on the corneas were imaged using a stereomicroscope. Western blot analysis for HSV-1 proteins was performed to verify HSV-1 infection of the cornea. Using the ex vivo model, zinc oxide tetrapods were tested for their anti-HSV-1 potential, and a cytokine profile was developed to assess the effects of the treatment. Results Cultured corneas and the use of β-galactosidase-expressing HSV-1(KOS)tk12 virus can provide an attractive ex vivo model to visualize and study HSV-1 entry and spread of the infection in tissues. We found that unlike cultured HCE cells, which demonstrated nearly 100% infectivity, HSV-1 infection of the cultured cornea was more restrictive and took longer to develop. We also found that the zinc oxide tetrapod–shaped nano- and microstructures inhibited HSV infection of the cultured cells, as well as the cultured corneas. The cytokine profile of the infected samples was consistent with previous studies of HSV-1 corneal infection. Conclusions The ability to visualize HSV-1 growth and spread in corneal tissues can provide new details about HSV-1 infection of the cornea and the efficacy of new cornea-specific antiviral drug candidates. The ex vivo model also demonstrates antiviral effects of zinc oxide tetrapods and adequately portrays the drug delivery issues that cornea-specific treatments

  17. Diabetic cornea wounds produce significantly weaker electric signals that may contribute to impaired healing

    OpenAIRE

    Yunyun Shen; Trisha Pfluger; Fernando Ferreira; Jiebing Liang; Navedo, Manuel F; Qunli Zeng; Brian Reid; Min Zhao

    2016-01-01

    Wounds naturally produce electric signals which serve as powerful cues that stimulate and guide cell migration during wound healing. In diabetic patients, impaired wound healing is one of the most challenging complications in diabetes management. A fundamental gap in knowledge is whether diabetic wounds have abnormal electric signaling. Here we used a vibrating probe to demonstrate that diabetic corneas produced significantly weaker wound electric signals than the normal cornea. This was conf...

  18. Hyperglycemia-induced abnormalities in rat and human corneas: the potential of second harmonic generation microscopy.

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    Gaël Latour

    Full Text Available BACKGROUND: Second Harmonic Generation (SHG microscopy recently appeared as an efficient optical imaging technique to probe unstained collagen-rich tissues like cornea. Moreover, corneal remodeling occurs in many diseases and precise characterization requires overcoming the limitations of conventional techniques. In this work, we focus on diabetes, which affects hundreds of million people worldwide and most often leads to diabetic retinopathy, with no early diagnostic tool. This study then aims to establish the potential of SHG microscopy for in situ detection and characterization of hyperglycemia-induced abnormalities in the Descemet's membrane, in the posterior cornea. METHODOLOGY/PRINCIPAL FINDINGS: We studied corneas from age-matched control and Goto-Kakizaki rats, a spontaneous model of type 2 diabetes, and corneas from human donors with type 2 diabetes and without any diabetes. SHG imaging was compared to confocal microscopy, to histology characterization using conventional staining and transmitted light microscopy and to transmission electron microscopy. SHG imaging revealed collagen deposits in the Descemet's membrane of unstained corneas in a unique way compared to these gold standard techniques in ophthalmology. It provided background-free images of the three-dimensional interwoven distribution of the collagen deposits, with improved contrast compared to confocal microscopy. It also provided structural capability in intact corneas because of its high specificity to fibrillar collagen, with substantially larger field of view than transmission electron microscopy. Moreover, in vivo SHG imaging was demonstrated in Goto-Kakizaki rats. CONCLUSIONS/SIGNIFICANCE: Our study shows unambiguously the high potential of SHG microscopy for three-dimensional characterization of structural abnormalities in unstained corneas. Furthermore, our demonstration of in vivo SHG imaging opens the way to long-term dynamical studies. This method should be easily

  19. Material Properties from Air Puff Corneal Deformation by Numerical Simulations on Model Corneas

    Science.gov (United States)

    Dorronsoro, Carlos; de la Hoz, Andrés; Marcos, Susana

    2016-01-01

    Objective To validate a new method for reconstructing corneal biomechanical properties from air puff corneal deformation images using hydrogel polymer model corneas and porcine corneas. Methods Air puff deformation imaging was performed on model eyes with artificial corneas made out of three different hydrogel materials with three different thicknesses and on porcine eyes, at constant intraocular pressure of 15 mmHg. The cornea air puff deformation was modeled using finite elements, and hyperelastic material parameters were determined through inverse modeling, minimizing the difference between the simulated and the measured central deformation amplitude and central-peripheral deformation ratio parameters. Uniaxial tensile tests were performed on the model cornea materials as well as on corneal strips, and the results were compared to stress-strain simulations assuming the reconstructed material parameters. Results The measured and simulated spatial and temporal profiles of the air puff deformation tests were in good agreement (< 7% average discrepancy). The simulated stress-strain curves of the studied hydrogel corneal materials fitted well the experimental stress-strain curves from uniaxial extensiometry, particularly in the 0–0.4 range. Equivalent Young´s moduli of the reconstructed material properties from air-puff were 0.31, 0.58 and 0.48 MPa for the three polymer materials respectively which differed < 1% from those obtained from extensiometry. The simulations of the same material but different thickness resulted in similar reconstructed material properties. The air-puff reconstructed average equivalent Young´s modulus of the porcine corneas was 1.3 MPa, within 18% of that obtained from extensiometry. Conclusions Air puff corneal deformation imaging with inverse finite element modeling can retrieve material properties of model hydrogel polymer corneas and real corneas, which are in good correspondence with those obtained from uniaxial extensiometry

  20. Ocular allergic inflammation: interaction between the cornea and conjunctiva.

    Science.gov (United States)

    Fukuda, Ken; Nishida, Teruo

    2010-11-01

    Severe ocular allergic diseases such as vernal keratoconjunctivitis are characterized not only by conjunctival allergic inflammation, including infiltration of T helper 2 cells and eosinophils into the conjunctiva, but also by various corneal disorders such as persistent epithelial defects and shield ulcer. Although the cornea and conjunctiva are thought to influence each other during ocular allergic inflammation, direct evidence for interaction between these tissues in vivo has been lacking. Eosinophils and eosinophil-derived factors are implicated in the pathogenesis of corneal lesions associated with ocular allergy, with cytotoxic granule proteins such as major basic protein and matrix metalloproteinase 9 derived from eosinophils having been detected in shield ulcer. Major basic protein exhibits cytotoxic effects in cultured corneal epithelial cells and inhibits corneal epithelial wound healing in organ culture, whereas matrix metalloproteinase 9 can degrade the corneal epithelial basement membrane. In vitro studies have revealed that cytokines and other inflammatory mediators directly impair the barrier function of corneal epithelial cells and increase the expression of chemokines and adhesion molecules by corneal stromal fibroblasts, effects that may enhance allergic inflammation. We have recently shown that removal of the corneal epithelium augmented late-phase clinical signs and conjunctival eosinophilia, whereas conjunctival inflammation delayed corneal epithelial wound healing, in a rat model of ocular allergy. Conjunctival allergic inflammation and corneal epithelial disorders thus interact with each other in vivo to generate a vicious cycle, interruption of which might provide the basis for novel approaches to the treatment of severe ocular allergy.

  1. Cross-linking da cornea: protocolo padrão

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    Marcony R. Santhiago

    Full Text Available RESUMO O objetivo desta revisão é de determinar as indicações e eficácia da cirurgia que promove novas ligações covalentes entre as fibras de colágeno da córnea, conhecida como Cross-Linking (CXL, assim como esclarecer seus objetivos. O ceratocone é uma doença ectasica da córnea, bilateral, assimétrica, que, principalmente, cursa com encurvamento e afinamentos progressivo, e se inicia em geral na segunda década de vida. O uso primário do CXL tem sido na interrupção da progressão do Ceratocone. Apesar do conhecido encurvamento no estroma da córnea ocorrer nesses pacientes, a fisiopatologia por trás do ceratocone ainda é desconhecida e parece ser multifatorial. Pela evidencia literária disponível até o momento, o CXL da córnea esta, portanto indicado nos pacientes com doença em progressão. Concluímos que existe evidencia suficiente para afirmar que o CXL da córnea é eficaz na estabilização da doença ectásica da cornea.

  2. Polymicrobial Infection of the Cornea Due to Contact Lens Wear

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    Selçuk Sızmaz

    2016-04-01

    Full Text Available A 38-year-old male presented with pain and redness in his left eye. He had a history of wearing contact lenses. His ophthalmic examination revealed a large corneal ulcer with surrounding infiltrate. Cultures were isolated from the contact lenses, lens solutions, storage cases, and conjunctivae of both eyes and also corneal scrapings of the left eye. Fortified vancomycin and amikacin drops were started hourly. Culture results of conjunctivae of each eye and left cornea were positive for Pseudomonas aeruginosa; cultures from the contact lenses, lens solution and storage case of both eyes revealed Pseudomonas aeruginosa and Alcaligenes xylosoxidans. Polymerase chain reaction of the corneal scraping was positive for Acanthameoba. The topical antibiotics were changed with ones that both bacteria were sensitive to and anti-amoebic therapy was added. The patient had two recurrences following initial presentation despite intensive therapy. Keratitis occurred due to multiple pathogens; the relapsing course despite adequate therapy is potentially associated with this polymicrobial etiology.

  3. Wound-Healing Studies in Cornea and Skin: Parallels, Differences and Opportunities

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    Anne Bukowiecki

    2017-06-01

    Full Text Available The cornea and the skin are both organs that provide the outer barrier of the body. Both tissues have developed intrinsic mechanisms that protect the organism from a wide range of external threats, but at the same time also enable rapid restoration of tissue integrity and organ-specific function. The easy accessibility makes the skin an attractive model system to study tissue damage and repair. Findings from skin research have contributed to unravelling novel fundamental principles in regenerative biology and the repair of other epithelial-mesenchymal tissues, such as the cornea. Following barrier disruption, the influx of inflammatory cells, myofibroblast differentiation, extracellular matrix synthesis and scar formation present parallel repair mechanisms in cornea and skin wound healing. Yet, capillary sprouting, while pivotal in proper skin wound healing, is a process that is rather associated with pathological repair of the cornea. Understanding the parallels and differences of the cellular and molecular networks that coordinate the wound healing response in skin and cornea are likely of mutual importance for both organs with regard to the development of regenerative therapies and understanding of the disease pathologies that affect epithelial-mesenchymal interactions. Here, we review the principal events in corneal wound healing and the mechanisms to restore corneal transparency and barrier function. We also refer to skin repair mechanisms and their potential implications for regenerative processes in the cornea.

  4. Human cornea wound healing in organ culture after Er:YAG laser ablation

    Science.gov (United States)

    Shen, Jin-Hui; Joos, Karen M.; Robinson, Richard D.; Shetlar, Debra J.; O'Day, Denis M.

    1998-06-01

    Purpose: To study the healing process in cultured human corneas after Er:YAG laser ablation. Methods: Human cadaver corneas within 24 hours post mortem were ablated with a Q- switched Er:YAG laser at 2.94 micrometer wavelength. The radiant exposure was 500 mJ/cm2. The cornea was cultured on a tissue supporting frame immediately after the ablation. Culture media consisted of 92% minimum essential media, 8% fetal bovine serum, 0.125% HEPES buffer solution, 0.125% gentamicin, and 0.05% fungizone. The entire tissue frame and media container were kept in an incubator at 37 degrees Celsius and 5% CO2. Serial macroscopic photographs of the cultured corneas were taken during the healing process. Histology was performed after 30 days of culture. Results: A clear ablated crater into the stroma was observed immediately after the ablation. The thickness of thermal damage ranges between 1 and 25 micrometer. Haze development within the crater varies from the third day to the fourteenth day according to the depth and the roughness of the crater. Histologic sections of the cultured cornea showed complete re- epithelization of the lased area. Loose fibrous tissue is observed filling the ablated space beneath the epithelium. The endothelium appeared unaffected. Conclusions: The intensity and time of haze development appears dependent upon the depth of the ablation. Cultured human corneas may provide useful information regarding the healing process following laser ablation.

  5. Intrastromal Injection of China Painting Ink in Corneas of Male Rabbits: Clinical and Histological Study

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    Alahmady Hamad Alsmman Hassan

    2016-01-01

    Full Text Available Background. Many patients with corneal opacity or complicated cataract in blind eye ask for cosmoses. In this study we tried to investigate the staining of corneas of male rabbits by Rotring China painting ink and to study the histological changes. Method. 10 eyes of 10 male Baladi Egyptian rabbits were injected (0.1 mL intrastromally in the cornea by the use of China painting ink (Rotring Tinta China through insulin syringe (27-gauge needle by single injection; clinical follow-up is for 6 months and lastly the rabbits were scarified and the stained eyes were enucleated for histological analysis. Results. Clinically the stain was stable in color and distribution in corneas with no major complications. Histological results of the stained rabbit corneas showed blackish pigmentation in the corneal stroma without any inflammatory cellular infiltration. Some fibroblast cells had pigment granules in their cytoplasm in the adjacent layers. Conclusion. Corneal staining by China painting ink is effective and safe in staining of male rabbits cornea; however further study in human corneas with longer follow-up period is advisable.

  6. Effect of epithelial debridement on human cornea proteoglycans

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    E.S. Soriano

    2001-03-01

    Full Text Available Corneal transparency is attributed to the regular spacing and diameter of collagen fibrils, and proteoglycans may play a role in fibrillogenesis and matrix assembly. Corneal scar tissue is opaque and this opacity is explained by decreased ultrastructural order that may be related to proteoglycan composition. Thus, the objectives of the present study were to characterize the proteoglycans synthesized by human corneal explants and to investigate the effect of mechanical epithelial debridement. Human corneas unsuitable for transplants were immersed in F-12 culture medium and maintained under tissue culture conditions. The proteoglycans synthesized in 24 h were labeled metabolically by the addition of 35S-sulfate to the medium. These compounds were extracted by 4 M GuHCl and identified by a combination of agarose gel electrophoresis, enzymatic degradation with protease and mucopolysaccharidases, and immunoblotting. Decorin was identified as the main dermatan sulfate proteoglycan and keratan sulfate proteoglycans were also prominent components. When the glycosaminoglycan side chains were analyzed, only keratan sulfate and dermatan sulfate were detected (~50% each. Nevertheless, when these compounds were 35S-labeled metabolically, the label in dermatan sulfate was greater than in keratan sulfate, suggesting a lower synthesis rate for keratan sulfate. 35S-Heparan sulfate also appeared. The removal of the epithelial layer caused a decrease in heparan sulfate labeling and induced the synthesis of dermatan sulfate by the stroma. The increased deposit of dermatan sulfate proteoglycans in the stroma suggests a functional relationship between epithelium and stroma that could be related to the corneal opacity that may appear after epithelial cell debridement.

  7. Bevacizumab application delays epithelial healing in rabbit cornea.

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    Kim, Tae-im; Chung, Jae Lim; Hong, Jin Pyo; Min, Kyung; Seo, Kyoung Yul; Kim, Eung Kweon

    2009-10-01

    Vascular endothelial growth factor (VEGF) is essential for neovascularization, but the use of anti-VEGF therapies to inhibit neovascularization may influence epithelial wound healing. Here, the effects of bevacizumab on corneal epithelial wound healing time in rabbit models, cell proliferation, and expression of integrins in human corneal epithelial and fibroblast cells were evaluated. To compare epithelial wound healing times, epithelial defect sizes were measured after application of bevacizumab topical eye drops at 0, 0.5, 1.0, 1.5, 2.5, or 5 mg/mL, twice daily, to mechanically debrided epithelia of rabbit corneas. The cellular covering of wounded areas and expression of Ki67 were assessed after scrape injuries in cultures of human corneal epithelial and fibroblast cells. Expression of cell surface integrins and collagens was measured using plates coated with mouse monoclonal antibodies against human adhesion molecules, and relevant mRNA levels were assessed by reverse-transcription-polymerase chain reaction (RT-PCR). The application of bevacizumab topical eye drops at 1.0, 1.5, 2.5, or 5 mg/mL delayed rabbit corneal epithelial healing. Cell cultures growing under high concentrations of bevacizumab showed delay in the proliferation of corneal epithelial and fibroblast cells. Surface expression of mRNA encoding integrins and collagens were decreased by 1.5 mg/mL of bevacizumab. Bevacizumab delayed corneal epithelial wound healing and inhibited integrin expression. When bevacizumab is used to reduce the development of new corneal vessels, slight delays in epithelial wound healing are possible and cellular proliferation is to be expected.

  8. Use of glycerol-preserved corneas for corneal transplants

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    Neeti Gupta

    2017-01-01

    Full Text Available Purpose: This study was carried out to see the results of glycerol-preserved cornea (GPC in emergency situation when fresh corneal tissue was not available. The aim was to study the outcome of corneal transplantation using GPC. Methods: This was a retrospective study. The medical records of all the patients were reviewed, who underwent keratoplasty using “GPC” during the period from October 2011 to December 2015. The indication of keratoplasty, duration of preservation of the GPC, and its outcome were analyzed. Descriptive statistics were applied. Results: Out of the 222 penetrating keratoplasty (PKP performed over the study period, the GPC was used in 34 patients (males = 31, 91.2% aged 15–74 years. Therapeutic keratoplasty was performed in all cases in this cohort except one in which tectonic keratoplasty was done. The primary indication of PKP (91.2% was infectious keratitis. Of these, 20 (64.5% patients presented with perforated corneal ulcers. Post-PKP, ocular anatomy was preserved in 91.2%, and visual acuity of perception of light positive and accurate projection of rays in all the quadrants was obtained in 76.5% cases. Complications included glaucoma (n = 12, 35.1%, phthisis bulbi (n = 2, 5.9%, and graft reinfection and endophthalmitis after PKP (n = 1, 2.9%. The secondary procedure post-GPC and PKP were trabeculectomy with mitomycin C (n = 7, 58.3% in patients not controlled on topical antiglaucoma medication. Optical keratoplasty was performed in (n = 3 8.8% patients and triple procedure in (n = 2 5.8% patients with good visual acuity postprocedure. Conclusions: Acellular GPCs are useful in emergency keratoplasty to avoid loss of vision and can save the eye.

  9. Trasplante de córnea Cornea transplant

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    A. Garralda

    2006-08-01

    Full Text Available La queratoplastia o trasplante de córnea es una de las técnicas quirúrgicas más antiguas de la oftalmología cuyas indicaciones son: 1 tectónicas, para preservar la anatomía e integridad corneal, 2 clínicas, para eliminar el tejido corneal inflamado en casos refractarios al tratamiento médico, 3 ópticas, para mejorar la agudeza visual y 4 cosméticas para mejorar el aspecto del ojo. El perfeccionamiento en la técnica y en el instrumental, así como en el tratamiento postoperatorio y en los medios de conservación del tejido donante han mejorado la supervivencia de los injertos realizados. El Modelo Pamplona de coordinación de trasplantes del Hospital Virgen del Camino (HVC está considerado como original y único en España, y en la logística de este programa se incluye el protocolo de detección y extracción de córneas así como el de queratoplastias.The keratoplasty, or corena transplant, is one of the oldest surgical techniques in opthalmology, whose indication are: 1 tectonic, in order to preserve corneal anatomy and integrity; 2 clinical, in order to eliminate the inflamed corneal tissue in cases refractory to medical treatment; 3 optical, in order to improve visual acuity; and 4 cosmetic, in order to improve the appearance of the eye. Improvements in technique and instruments, as well as in post-operative treatment and the means of preserving donated tissue, have improved survival of the grafts. The Pamplona Model of transplant coordination of the Virgen del Camino Hospital is considered to be original and unique in Spain. The logistics of this program include the protocol for detection and extraction of corneas as well as for keratoplasties.

  10. Gene transfer of integration defective anti-HSV-1 meganuclease to human corneas ex vivo.

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    Elbadawy, H M; Gailledrat, M; Desseaux, C; Salvalaio, G; Di Iorio, E; Ferrari, B; Bertolin, M; Barbaro, V; Parekh, M; Gayon, R; Munegato, D; Franchin, E; Calistri, A; Palù, G; Parolin, C; Ponzin, D; Ferrari, S

    2014-03-01

    Corneal graft rejection is a major problem in chronic herpetic keratitis (HK) patients with latent infection. A new class of antiviral agents targeting latent and active forms of herpes simplex virus type 1 (HSV-1) is importantly required. Meganucleases are sequence-specific homing endonucleases capable of inducing DNA double-strand breaks. A proof-of-concept experiment has shown that tailor-made meganucleases are efficient against HSV-1 in vitro. To take this work a step forward, we hypothesized that the pre-treatment of human corneas in eye banks using meganuclease-encoding vectors will allow HK patients to receive a medicated cornea to resist the recurrence of the infection and the common graft rejection problem. However, this strategy requires efficient gene delivery to human corneal endothelium. Using recombinant adeno-associated virus, serotype 2/1 (rAAV2/1), efficient gene delivery of a reporter gene was demonstrated in human corneas ex vivo. The optimum viral dose was 3.7 × 10(11) VG with an exposure time of 1 day, followed by 6 days incubation in de-swelling medium. In addition, 12 days incubation can result in transgene expression in excess of 70%. Using similar transduction conditions, meganuclease transgene expression was detected in 39.4% of the endothelial cells after 2 weeks in culture. Reduction of the total viral load in the media and the endothelial cells of corneas infected with HSV-1 was shown. Collectively, this work provides information about the optimum conditions to deliver genetic material to the cornea, and demonstrates for the first time the expression of meganuclease in human corneas ex vivo and its antiviral activity. In conclusion, we demonstrate that the treatment of human corneas in eye banks before transplantation is a new approach to address the unmet clinical needs in corneal diseases.

  11. Diabetic cornea wounds produce significantly weaker electric signals that may contribute to impaired healing.

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    Shen, Yunyun; Pfluger, Trisha; Ferreira, Fernando; Liang, Jiebing; Navedo, Manuel F; Zeng, Qunli; Reid, Brian; Zhao, Min

    2016-06-10

    Wounds naturally produce electric signals which serve as powerful cues that stimulate and guide cell migration during wound healing. In diabetic patients, impaired wound healing is one of the most challenging complications in diabetes management. A fundamental gap in knowledge is whether diabetic wounds have abnormal electric signaling. Here we used a vibrating probe to demonstrate that diabetic corneas produced significantly weaker wound electric signals than the normal cornea. This was confirmed in three independent animal models of diabetes: db/db, streptozotocin-induced and mice fed a high-fat diet. Spatial measurements illustrated that diabetic cornea wound currents at the wound edge but not wound center were significantly weaker than normal. Time lapse measurements revealed that the electric currents at diabetic corneas lost the normal rising and plateau phases. The abnormal electric signals correlated significantly with impaired wound healing. Immunostaining suggested lower expression of chloride channel 2 and cystic fibrosis transmembrane regulator in diabetic corneal epithelium. Acute high glucose exposure significantly (albeit moderately) reduced electrotaxis of human corneal epithelial cells in vitro, but did not affect the electric currents at cornea wounds. These data suggest that weaker wound electric signals and impaired electrotaxis may contribute to the impaired wound healing in diabetes.

  12. Prevalence and Associations of Steep Cornea/Keratoconus in Greater Beijing. The Beijing Eye Study

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    Xu, Liang; Wang, Ya Xing; Guo, Yin; You, Qi Sheng; Jonas, Jost B.

    2012-01-01

    Purpose To evaluate the prevalence and associated factors of steep cornea/keratoconus in the adult Chinese population. Methods The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6±9.8 years (range: 50–93 years). A detailed ophthalmic examination was performed including optical low-coherence reflectometry. Steep cornea/keratoconus were defined as an anterior corneal refractive power exceeding 48 diopters. Results Mean refractive power of the cornea was 43.16±1.45 diopters (range: 36.51 to 48.46 diopters; flattest meridian) and 43.98±1.52 diopters (range: 37.00 to 52.88 diopters; steepest meridian). A steep cornea/keratoconus defined as corneal refractive power of ≥48 diopters and ≥49 diopters was detected in 27 subjects (prevalence rate: 0.9±0.2%) and 6 (0.2± 0.1%) subjects, respectively. Presence of steep cornea/keratoconus was associated with shorter axial length (Pkeratoconus defined as corneal refractive power of 48+ diopters has a prevalence of 0.9±0.2% among Chinese aged 50 years and above. Its prevalence was significantly associated with the ocular parameters of shorter axial length, smaller interpupillary distance, higher cylindrical and myopic refractive error and lower best corrected visual acuity, however, with none of the systemic parameters tested. PMID:22792169

  13. Outcomes of shunt tube coverage with glycerol preserved cornea versus pericardium.

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    Wigton, Eric; C Swanner, Jason; Joiner, Wade; Feldman, Alex; McGwin, Gerald; Huisingh, Carrie; Curcio, Christine A; Girkin, Christopher A

    2014-01-01

    Pericardium is a biomaterial widely used for covering the outflow tubes of glaucoma drainage devices. Recently, glycerol preserved cornea has been introduced as an alternative that offers durability and improved cosmesis because of its clarity. We retrospectively reviewed 262 patients in the University of Alabama Birmingham Glaucoma Service who underwent shunt procedures using either cornea tissue or pericardium to cover the tube. The primary outcome measure was the number of erosions of the covering material. Nine out of 101 (8.9%) patients in the pericardium covered group experienced an erosion compared with 3 out of 161 (1.9%) in the cornea covered group. A significant difference was reached with P=0.0125. Median follow-up was 440 days for the cornea group and 331 days for the pericardium group. The type of glaucoma (primary open-angle glaucoma vs. secondary glaucoma) was not associated with the risk of erosion (odds ratio, 0.501; 95% confidence interval, 0.204-1.234). The median time to exposure was 252 days in the pericardium group and 440 days in the cornea group (P=0.0017).

  14. Donor cornea preparation in partial big bubble deep anterior lamellar keratoplasty

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    Lim L

    2014-02-01

    Full Text Available Li Lim,1 Samuel Wen Yan Lim21Corneal and External Eye Disease Service, Singapore National Eye Centre, 2Yong Loo Lin School of Medicine, National University of Singapore, SingaporeBackground: The purpose of this paper is to describe a technique of donor cornea preparation to ensure good graft-host apposition in incomplete big bubble deep anterior lamellar keratoplasty.Methods: Following a partial-thickness trephination, manual dissection and excision of corneal stroma was performed. Anwar's big-bubble technique involving a deep stromal air injection was then initiated. However, the big bubble could not extend to the trephination edge and the peripheral residual corneal stroma could not be removed. Donor cornea preparation involving trimming of the posterior lip of the corneal button was then performed and good graft-host apposition was obtained without graft over-ride.Results: We performed peripheral donor cornea trimming prior to allograft placement in order to ensure good graft-host apposition. Postoperatively, best-corrected visual acuity in both eyes was 6/7.5.Conclusion: Donor cornea preparation involving trimming of the posterior lip of the corneal button is a useful technique in instances where the big bubble does not extend to the trephination edge and ensures good graft-host apposition.Keywords: deep anterior lamellar keratoplasty, incomplete Anwar big bubble deep anterior lamellar keratoplasty, donor cornea preparation

  15. Cornea nerve fiber quantification and construction of phenotypes in patients with fibromyalgia

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    Oudejans, Linda; He, Xuan; Niesters, Marieke; Dahan, Albert; Brines, Michael; van Velzen, Monique

    2016-01-01

    Cornea confocal microscopy (CCM) is a novel non-invasive method to detect small nerve fiber pathology. CCM generally correlates with outcomes of skin biopsies in patients with small fiber pathology. The aim of this study was to quantify the morphology of small nerve fibers of the cornea of patients with fibromyalgia in terms of density, length and branching and further phenotype these patients using standardized quantitative sensory testing (QST). Small fiber pathology was detected in the cornea of 51% of patients: nerve fiber length was significantly decreased in 44% of patients compared to age- and sex-matched reference values; nerve fiber density and branching were significantly decreased in 10% and 28% of patients. The combination of the CCM parameters and sensory tests for central sensitization, (cold pain threshold, mechanical pain threshold, mechanical pain sensitivity, allodynia and/or windup), yielded four phenotypes of fibromyalgia patients in a subgroup analysis: one group with normal cornea morphology without and with signs of central sensitization, and a group with abnormal cornea morphology parameters without and with signs of central sensitization. In conclusion, half of the tested fibromyalgia population demonstrates signs of small fiber pathology as measured by CCM. The four distinct phenotypes suggest possible differences in disease mechanisms and may require different treatment approaches. PMID:27006259

  16. Stromal Interleukin-1 Expression in the Cornea after Haze-associated Injury

    Science.gov (United States)

    Barbosa, F. L.; Chaurasia, S.; Kaur, H.; de Medeiros, F. W.; Agrawal, V.; Wilson, S. E.

    2010-01-01

    The purpose of this study was to determine whether myofibroblasts or other cells in the stroma in the cornea produce interleukin (IL)-1α or IL-1β that could modulate myofibroblast viability in corneas with haze after photorefractive keratectomy (PRK). Twenty-four female rabbits had haze-generating PRK for 9 diopters of myopia and were sacrificed at 1 week, 2 weeks, 3 weeks or 4 weeks after surgery. Corneal rims were removed, frozen in OCT at −80°C, and analyzed by immunocytochemistry using primary antibodies to IL-1α, IL-1β and alpha smooth muscle actin (SMA). Double immunostaining was performed for the co-localization of SMA with IL-1α or IL-1β. Central dense haze and peripheral slight haze regions of each cornea were analyzed. SMA+ cells that expressed IL-1α protein were detected in both regions of the corneas at most time points following PRK. However, in the haze region at the 1, 3 and 4 week time points, significantly more (pcorneal fibroblasts, keratocytes, or inflammatory cells may produce IL-1α and/or IL-1β that could act in paracrine fashion to regulate myofibroblast apoptosis—especially in the region where there is haze in the cornea after PRK was performed and SMA+ myofibroblasts are present at higher density. However, some SMA+ myofibroblasts themselves produce IL-1α and/or IL-1β, suggesting that myofibroblast viability could also be regulated via autocrine mechanisms. PMID:20603114

  17. Systematic assessment of microneedle injection into the mouse cornea

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    Matthaei Mario

    2012-06-01

    Full Text Available Abstract Background Corneal intrastromal injection is an important mode of gene-vector application to subepithelial layers. In a mouse model, this procedure is substantially complicated by the reduced corneal dimensions. Furthermore, it may be difficult to estimate the corneal area reached by the volume of a single injection. This study aimed to investigate intrastromal injections into the mouse cornea using different microneedles and to quantify the effect of injecting varying volumes. A reproducible injection technique is described. Methods Forty eyes of 20 129 Sv/J mice were tested. India ink was intrastromally injected using 30° beveled 33 G needles, tri-surface 25° beveled 35 G needles, or hand-pulled and 25° beveled glass needles. Each eye received a single injection of a volume of 1 or 2 μL. Corneoscleral buttons were fixed and flat mounted for computer-assisted quantification of the affected corneal area. Histological assessment was performed to investigate the intrastromal location of the injected dye. Results A mean corneal area of 5.0 ±1.4 mm2 (mean ± SD and 7.7 ±1.4 mm2 was covered by intrastromal injections of 1 and 2 μL, respectively. The mean percentage of total corneal area reached ranged from 39% to 53% for 1 μL injections, and from 65% to 81% for 2 μL injections. Injections using the 33 G needles tended to provide the highest distribution area. Perforation rates were 8% for 30° beveled 33 G needles and 44% for tri-surface beveled 35 G needles. No perforation was observed with glass needle; however, intrastromal breakage of needle tips was noted in 25% of these cases. Conclusions Intracorneal injection using a 30° beveled 33 G needle was safe and effective. The use of tri-surface beveled 35 G needles substantially increased the number of corneal perforations. Glass needles may break inside the corneal stroma. Injections of 1 μL and 2 μL resulted in an overall mean of 49% and 73% respectively

  18. Effective spherical aberration of the cornea as a quantitative descriptor in corneal topography.

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    Seiler, T; Reckmann, W; Maloney, R K

    1993-01-01

    Following excimer laser photorefractive keratectomy and other refractive surgical procedures, complaints of halos, glare, and monocular diplopia are common. These procedures increase the asphericity of the cornea, which may cause the optical distortions. We used ray tracing techniques to estimate the longitudinal monochromatic aberration of the cornea from the measured corneal topography (effective spherical aberration) in 15 normal eyes with varying degrees of astigmatism and in ten eyes after photorefractive keratectomy. Best spherical corrected visual acuity in the astigmatic eyes was highly correlated with effective spherical aberration (r = -0.9527, P < .001). In the eyes that had photorefractive keratectomy, the effective spherical aberration was highly correlated with measured glare visual acuity (r = 0.875, P < .002). These results suggest that effective spherical aberration is a valuable topographic measure that provides information about the optical performance of aspheric corneas.

  19. Study of noncontact air-puff applanation tonometry IOP measurement on irregularly-shaped corneas

    Science.gov (United States)

    Wang, Wai W.; Wang, Kuo-Jen; Tsai, Che-Liang; Wang, I.-Jong

    2017-04-01

    Abnormal corneas with corneal tissue defects like ulceration, melting, laceration, thinning scar, keratoconus etc., poses special challenges for ophthalmologist to measure intraocular pressure (IOP) correctly using air-puff noncontact applanation tonometry. Here, we propose an novel model, Abnormal Applanation IOP Model (AAIOP), to simulate IOP in these abnormal corneas on an air-puff noncontact applanation tonometry system, and the simulated IOP results are correctly fit in those of IOP measured database on human eyes of 91,024 patients (174,666 eyes)1). Our simulated IOP indicates that every 10 μm of central corneal thickness change results in 0.36 mmHg of IOP change. Using our simulation model, the IOP on abnormal eyes with irregularly-shaped corneas can be correctly expected and reported.

  20. Holographic interferometry of intact and radially incised human eye-bank corneas.

    Science.gov (United States)

    Smolek, M K

    1994-05-01

    Many methods to measure corneal elasticity destroy the tissue and thereby produce erroneous results. Holographic interferometry, a highly precise nondestructive optical comparison technique, was used to evaluate corneal elasticity of intact eye-bank eyes. A double-pulse holographic interferometer operating at 632.8 nm was used to measure corneal deformation in 20 whole-globe eyes from donors 45 to 83 years of age for intraocular pressures from 16 mm Hg to 21 mm Hg. Stress was computed from LaPlace's law, and arc length strain was derived from z-axis distention of the central cornea. The stress-strain relationship in the normal physiological range of intraocular pressure was linear with a Young's elastic modulus of 1.03 gigapascals for the central cornea (r = 0.999). During interferometry of radial keratotomy of the cornea, interference fringe patterns developed in association with each incision as it was made. When four incisions were placed deep along each of the primary semimeridians, the fringe pattern developed as expected, based on current keratotomy models. When incisions were shallow (approximately 50% depth) and placed asymmetrically along the nasal, temporal, and superior semimeridians, the resulting surface strain was symmetrical about the central cornea, forming an annular pattern of interference fringes. These results indicate that when the cornea was stressed at physiological pressures as part of the intact whole globe, it was less elastic than excised corneal tissue tested by strip extensiometry. Radially incised corneas demonstrated strain patterns suggestive of inherent structural anisotropy with a possible inferior quadrant weakness.

  1. Differentially expressed wound healing-related microRNAs in the human diabetic cornea.

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    Vincent A Funari

    Full Text Available MicroRNAs are powerful gene expression regulators, but their corneal repertoire and potential changes in corneal diseases remain unknown. Our purpose was to identify miRNAs altered in the human diabetic cornea by microarray analysis, and to examine their effects on wound healing in cultured telomerase-immortalized human corneal epithelial cells (HCEC in vitro. Total RNA was extracted from age-matched human autopsy normal (n=6 and diabetic (n=6 central corneas, Flash Tag end-labeled, and hybridized to Affymetrix® GeneChip® miRNA Arrays. Select miRNAs associated with diabetic cornea were validated by quantitative RT-PCR (Q-PCR and by in situ hybridization (ISH in independent samples. HCEC were transfected with human pre-miR™miRNA precursors (h-miR or their inhibitors (antagomirs using Lipofectamine 2000. Confluent transfected cultures were scratch-wounded with P200 pipette tip. Wound closure was monitored by digital photography. Expression of signaling proteins was detected by immunostaining and Western blot. Using microarrays, 29 miRNAs were identified as differentially expressed in diabetic samples. Two miRNA candidates showing the highest fold increased in expression in the diabetic cornea were confirmed by Q-PCR and further characterized. HCEC transfection with h-miR-146a or h-miR-424 significantly retarded wound closure, but their respective antagomirs significantly enhanced wound healing vs. controls. Cells treated with h-miR-146a or h-miR-424 had decreased p-p38 and p-EGFR staining, but these increased over control levels close to the wound edge upon antagomir treatment. In conclusion, several miRNAs with increased expression in human diabetic central corneas were found. Two such miRNAs inhibited cultured corneal epithelial cell wound healing. Dysregulation of miRNA expression in human diabetic cornea may be an important mediator of abnormal wound healing.

  2. [Cornea bank of Lyon: from quality diagnosis to ISO 9001 certification].

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    Pascal, P; Chalochet, A; Damour, O

    2001-12-01

    The tissue and cell bank of the HCL (Hospices Civils de Lyon) has, since 10 June 1999, consisted of two sections with related activities: cell culture for the Skin Substitutes Laboratory (Laboratoire des Substituts Cutanés, LSC) and preservation of corneas at 31 degrees C for the Cornea Bank. As the LSC had been ISO 9001 certified since March 1997 our aim, since merger, was to raise the Cornea Bank to the same level of quality as the LSC, so as to coincide with the renewal of the LSC certificate in February 2000. The methods we used (project, quality control, analysis and process optimization) led us to receive official certification only nine months after the merger. The procedure started with a program of quality control at the Cornea Bank from February 1999 onwards, in order to list the work and equipment required, evaluate its documentation system and what was needed to incorporate this new activity into the existing system of quality assurance at the LSC. On the 7th March 2000, the Tissue and Cell Bank of the HCL obtained an ISO 9001 certificate for its combined functions. As well as achieving our objectives and the strong points highlighted by the auditor during the renewal process, this quality assessment revealed many advantages: improvements in the conservation of corneas, economies in staff replacement and reductions in both the cost of maintaining quality, the cost of the corneas themselves, etc. The decree 'Banque' no. 99-741 of 30th August 1999, which put in place the system of authorization of tissue banks in France, demands quality control. Our application for certification which started in early 1999 had anticipated this regulation. This helped us enormously when compiling the dossier accompanying the official request and was an essential element in obtaining the favourable response of the ASSAPS on 21 June 2000.

  3. [Pathological changes of the cornea in rabbits with hyphema and concurrent ocular hypertension].

    Science.gov (United States)

    Wang, Feng-yun; Lu, Xiao-he; Zhang, Cai-xia; Bai, Lang; Zhang, Jing; Zhong, Yan-yan; Wang, Shuang-shuang

    2010-03-01

    To evaluate the impact of hyphema secondary to high intraocular pressure on corneal pathology in rabbits. Thirty adult New Zealand rabbit were randomized into 3 equal groups, and in each rabbit, one eye served as the experimental eye with the other as the control eye. In the experimental eye, autoblood was injected into the anterior chamber to induce high intraocular pressure maintained for 3, 5, or 8 days. Only saline was injected into the control eye. After the injections, the cornea was observed with slit-lamp microscopy, and at 3, 5, or 8 days, the experimental and control eyes were taken from the 3 groups for microscopic examination of the corneas to detect the occurrence of cornea bloodstain with prolonged high intraocular pressure. Corneal edema, elastic fibers changes, growth of new blood vessels, changes of eosinophils, fibroblasts, lymphocytes and plasma cells, as well as the pathological changes of the corneal layers were observed and compared between the experimental and control eyes. Maintenance of high intraocular pressure for 8 days resulted in the most severe corneal edema and thickening, and histopathologically, the corneal stroma showed widened space between the elastic fibers and obvious fiber distortion. Neovascularization was seen in the marginal cornea where eosinophil infiltration occurred with a small number of lymphocytes, plasma cells and fiber cells. All the three groups showed more obvious edema in the posterior than in the anterior cornea. Prolonged hyphema with ocular hypertension results in aggravation of corneal edema, and corneal blood staining does not occur until 8 days of high intraocular pressure but corneal elastic fiber disruption can be seen, suggesting the impending irreversible pathological changes of cornea.

  4. Elastic microfibril distribution in the cornea: Differences between normal and keratoconic stroma.

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    White, Tomas L; Lewis, Philip N; Young, Robert D; Kitazawa, Koji; Inatomi, Tsutomu; Kinoshita, Shigeru; Meek, Keith M

    2017-06-01

    The optical and biomechanical properties of the cornea are largely governed by the collagen-rich stroma, a layer that represents approximately 90% of the total thickness. Within the stroma, the specific arrangement of superimposed lamellae provides the tissue with tensile strength, whilst the spatial arrangement of individual collagen fibrils within the lamellae confers transparency. In keratoconus, this precise stromal arrangement is lost, resulting in ectasia and visual impairment. In the normal cornea, we previously characterised the three-dimensional arrangement of an elastic fiber network spanning the posterior stroma from limbus-to-limbus. In the peripheral cornea/limbus there are elastin-containing sheets or broad fibers, most of which become microfibril bundles (MBs) with little or no elastin component when reaching the central cornea. The purpose of the current study was to compare this network with the elastic fiber distribution in post-surgical keratoconic corneal buttons, using serial block face scanning electron microscopy and transmission electron microscopy. We have demonstrated that the MB distribution is very different in keratoconus. MBs are absent from a region of stroma anterior to Descemet's membrane, an area that is densely populated in normal cornea, whilst being concentrated below the epithelium, an area in which they are absent in normal cornea. We contend that these latter microfibrils are produced as a biomechanical response to provide additional strength to the anterior stroma in order to prevent tissue rupture at the apex of the cone. A lack of MBs anterior to Descemet's membrane in keratoconus would alter the biomechanical properties of the tissue, potentially contributing to the pathogenesis of the disease. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. Morphological characterization of keratoconus-affected human corneas by SHG imaging and correlation analysis

    Science.gov (United States)

    Mercatelli, R.; Ratto, F.; Tatini, F.; Rossi, F.; Menabuoni, L.; Nicoletti, R.; Pini, R.; Pavone, Frederick; Cicchi, R.

    2016-03-01

    Keratoconus is an ophthalmic disease in which the cornea acquires an abnormal conical shape that prevents the correct focusing on the retina, causing visual impairment. The late diagnosis of keratoconus is among the principal causes of corneal transplantation surgery. In this study, we characterize the morphology of keratoconic corneas by means of the correlation of SHG images, finding that keratoconus can be diagnosed by analyzing the inclination of lamellae below Bowman's membrane. In addition, imaging performed with both sagittal and "en face" geometry demonstrated that this morphological features can be highlighted both ex vivo and in vivo.

  6. Second harmonic generation imaging of collagen fibrils in cornea and sclera

    Science.gov (United States)

    Han, Meng; Giese, Günter; Bille, Josef F.

    2005-07-01

    Collagen, as the most abundant protein in the human body, determines the unique physiological and optical properties of the connective tissues including cornea and sclera. The ultrastructure of collagen, which conventionally can only be resolved by electron microscopy, now can be probed by optical second harmonic generation (SHG) imaging. SHG imaging revealed that corneal collagen fibrils are regularly packed as a polycrystalline lattice, accounting for the transparency of cornea. In contrast, scleral fibrils possess inhomogeneous, tubelike structures with thin hard shells, maintaining the high stiffness and elasticity of the sclera.

  7. Computer driven optical keratometer and method of evaluating the shape of the cornea

    Science.gov (United States)

    Baroth, Edmund C. (Inventor); Mouneimme, Samih A. (Inventor)

    1994-01-01

    An apparatus and method for measuring the shape of the cornea utilize only one reticle to generate a pattern of rings projected onto the surface of a subject's eye. The reflected pattern is focused onto an imaging device such as a video camera and a computer compares the reflected pattern with a reference pattern stored in the computer's memory. The differences between the reflected and stored patterns are used to calculate the deformation of the cornea which may be useful for pre-and post-operative evaluation of the eye by surgeons.

  8. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study

    NARCIS (Netherlands)

    Barsingerhorn, A.D.; Boonstra, F.N.; Goossens, H.H.L.M.

    2017-01-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different

  9. Effect of topical fluoroquinolones on the expression of matrix metalloproteinases in the cornea

    OpenAIRE

    O'Brien Terrence P; Song Jae K; Hakim Melinda A; Reviglio Victor E

    2003-01-01

    Abstract Background Matrix metalloproteinases play an important role in extracellular matrix deposition and degradation. Based on previous clinical observations of corneal perforations during topical fluoroquinolone treatment, we decided to evaluate the comparative effects of various fluoroquinolone eye drops on the expression of matrix metalloproteinases (MMPs) in cornea. Methods Eighty female Lewis rats were divided into two experimental groups: intact and wounded corneal epithelium. Unifor...

  10. [Simple keratectomy in band-shaped degeneration of the cornea (author's transl)].

    Science.gov (United States)

    Kenyeres, P

    1980-01-01

    In a case of band-shaped keratopathy chemical solution of the opacity failed but it proved easy to remove Bowman's membrane by grasping it with a forceps and pulling it off. As a result the cornea became clear and vision improved up to 6/7ths.

  11. Wavelength-dependent ultraviolet induction of cyclobutane pyrimidine dimers in the human cornea.

    Science.gov (United States)

    Mallet, Justin D; Rochette, Patrick J

    2013-08-01

    Exposition to ultraviolet (UV) light is involved in the initiation and the progression of skin cancer. The genotoxicity of UV light is mainly attributed to the induction of cyclobutane pyrimidine dimers (CPDs), the most abundant DNA damage generated by all UV types (UVA, B and C). The human cornea is also exposed to the harmful UV radiations, but no UV-related neoplasm has been reported in this ocular structure. The probability that a specific DNA damage leads to a mutation and eventually to cellular transformation is influenced by its formation frequency. To shed light on the genotoxic effect of sunlight in the human eye, we have analyzed CPD induction in the cornea and the iris following irradiation of ex vivo human eyes with UVA, B or C. The extent of CPD induction was used to establish the penetrance of the different UV types in the human cornea. We show that UVB- and UVC-induced CPDs are concentrated in the corneal epithelium and do not penetrate deeply beyond this corneal layer. On the other hand, UVA wavelengths penetrate deeper and induce CPDs in the entire cornea and in the first layers of the iris. Taken together, our results are undoubtedly an important step towards better understanding the consequences of UV exposure to the human eye.

  12. Successful treatment of Fusarium keratitis with cornea transplantation and topical and systemic voriconazole.

    NARCIS (Netherlands)

    Klont, R.R.; Eggink, C.A.; Rijs, A.J.M.M.; Wesseling, P.; Verweij, P.E.

    2005-01-01

    A case of invasive Fusarium keratitis in a previously healthy male patient was treated successfully with cornea transplantation and systemic and topical voriconazole after treatment failure with topical amphotericin B and systemic itraconazole. Topical voriconazole was well tolerated, and, in conjun

  13. Influx of immunoglobulins from the vascular compartment into a grafted cornea

    NARCIS (Netherlands)

    VanDerVeen, G; Broersma, L; Bruyne, [No Value; Verhagen, C; VanRij, G; VanDerGaag, R; Ruijter, J

    1997-01-01

    Purpose. To determine the effect of a fresh corneal wound or a healed corneal Methods. F344 rats were immunized with human serum albumin (HSA) 1 week before an autologous rotational keratoplasty of the right cornea or 1 year after an autograft was performed. One group of rats also was treated with g

  14. Crosslinked collagen-gelatin-hyaluronic acid biomimetic film for cornea tissue engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yang; Ren, Li, E-mail: psliren@scut.edu.cn; Wang, Yingjun, E-mail: imwangyj@163.com

    2013-01-01

    Cornea disease may lead to blindness and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents the crosslinked collagen (Col)-gelatin (Gel)-hyaluronic acid (HA) films developed by making use of 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) as the crosslinker. The test results on the physical and biological properties indicate that the CGH631 film (the mass ratio of Col:Gel:HA = 6:3:1) has appropriate optical performance, hydrophilicity and mechanical properties. The diffusion properties of the CGH631 film to NaCl and tryptophan are also satisfactory and the measured data are 2.43 Multiplication-Sign 10{sup -6} cm{sup 2}/s and 7.97 Multiplication-Sign 10{sup -7} cm{sup 2}/s, respectively. In addition, cell viability studies demonstrate that the CGH631 film has good biocompatibility, on which human corneal epithelial cells attached and proliferated well. This biocompatible film may have potential use in cornea tissue engineering. - Highlights: Black-Right-Pointing-Pointer Crosslinked collagen-gelatin-hyaluronic acid films were fabricated in this study. Black-Right-Pointing-Pointer The film had appropriate physical properties. Black-Right-Pointing-Pointer Diffusion coefficient of the film was comparable with the human cornea. Black-Right-Pointing-Pointer HCEC viability studies confirmed the biocompatibility of the film.

  15. Model of Mass and Heat Transfer during Vacuum Freeze-Drying for Cornea

    Directory of Open Access Journals (Sweden)

    Zou Huifen

    2012-01-01

    Full Text Available Cornea is the important apparatus of organism, which has complex cell structure. Heat and mass transfer and thermal parameters during vacuum freeze-drying of keeping corneal activity are studied. The freeze-drying cornea experiments were operated in the homemade vacuum freeze dryer. Pressure of the freeze-drying box was about 50 Pa and temperature was about −10°C by controlled, and operating like this could guarantee survival ratio of the corneal endothelium over the grafting normal. Theory analyzing of corneal freeze-drying, mathematical model of describing heat and mass transfer during vacuum freeze-drying of cornea was established. The analogy computation for the freeze-drying of cornea was made by using finite-element computational software. When pressure of the freeze-drying box was about 50 Pa and temperature was about −10°C, time of double-side drying was 170 min. In this paper, a moving-grid finite-element method was used. The sublimation interface was tracked continuously. The finite-element mesh is moved continuously such that the interface position always coincides with an element node. Computational precision was guaranteed. The computational results were agreed with the experimental results. It proved that the mathematical model was reasonable. The finite-element software is adapted for calculating the heat and mass transfer of corneal freeze-drying.

  16. Use of corneas for transplant after self-inflicted eyeballs enucleation in the Italian law.

    Science.gov (United States)

    Montanari Vergallo, G; Pacella, E; Di Luca, A; Di Luca, N M; Cecchi, R; Marinelli, E

    2017-01-01

    The authors analyze from an ethical and legal point of view the case of a 37 year old man, hospitalized for four days because of a 'dissociative syndrome', who had introduced in both his orbits a portable radio antenna. Most likely, he completed the self-enuclation using his own hands. He was brought to the Ophtalmic Hospital by nurses who handed the two eyeballs to the physicians who ascertained that the corneas were intact. Then, they performed the conservative extraction. In the following days those corneas were transplanted (keratoplasty) on two subjects on the waiting list at that hospital. The case raises the question of whether it is lawful and ethically acceptable to take, for transplant use, the corneas of a mentally incapable patient who has excised his own eyeballs. The authors analyze the case from the angle of the Italian law and Oviedo Convention. Neither of them has a specific regulation on this topic. It is therefore necessary to apply general principles that holdvalidfor Italy and a variety of countries worldwide. Particularly, the choice to use the corneas for transplant did not prejudice the physical integrity of the patient, who could no longer utilize his own eyeballs. His self-determination has not been affected; in fact, he was not in the position to make a conscious decision. Additionally, the so-called "implied consent" could be applied. Therefore, the principle of human solidarity, which is the moral duty to benefit others, seems to prevail in the case at hand.

  17. Shape of the anterior cornea : Comparison of height data from 4 corneal topographers

    NARCIS (Netherlands)

    de Jong, Tim; Sheehan, Matthew T.; Dubbelman, Michiel; Koopmans, Steven A.; Jansonius, Nomdo M.

    2013-01-01

    PURPOSE: To compare the ability of clinical corneal topographers to describe the shape of the anterior cornea for optical modeling. SETTING: University Medical Center Groningen, Groningen, Netherlands. DESIGN: Cross-sectional study. METHODS: The anterior corneal shape of healthy subjects was assesse

  18. Spectroscopic measurements and terahertz imaging of the cornea using a rapid scanning terahertz time domain spectrometer

    Science.gov (United States)

    Wen-Quan, Liu; Yuan-Fu, Lu; Guo-Hua, Jiao; Xian-Feng, Chen; Zhi-Sheng, Zhou; Rong-Bin, She; Jin-Ying, Li; Si-Hai, Chen; Yu-Ming, Dong; Jian-Cheng, Lv

    2016-06-01

    Spectroscopic measurements and terahertz imaging of the cornea are carried out by using a rapid scanning terahertz time domain spectroscopy (THz-TDS) system. A voice coil motor stage based optical delay line (VCM-ODL) is developed to provide a rather simple and robust structure with both the high scanning speed and the large delay length. The developed system is used for THz spectroscopic measurements and imaging of the corneal tissue with different amounts of water content, and the measurement results show the consistence with the reported results, in which the measurement time using VCM-ODL is a factor of 360 shorter than the traditional motorized optical delay line (MDL). With reducing the water content a monotonic decrease of the complex permittivity of the cornea is observed. The two-term Debye relaxation model is employed to explain our experimental results, revealing that the fast relaxation time of a dehydrated cornea is much larger than that of a hydrated cornea and its dielectric behavior can be affected by the presence of the biological macromolecules. These results demonstrate that our THz spectrometer may be a promising candidate for tissue hydration sensing and practical application of THz technology. Project supported by the National Natural Science Foundation of China (Grant No. 61205101), the Shenzhen Municipal Research Foundation, China (Grant Nos. GJHZ201404171134305 and JCYJ20140417113130693), and the Marie Curie Actions-International Research Staff Exchange Scheme (IRSES) (Grant No. FP7 PIRSES-2013-612267).

  19. Pretreatment methods to improve nerve immunostaining in corneas from long-term fixed embryonic quail eyes

    Science.gov (United States)

    Barrett, J. E.; Wells, D. C.; Conrad, G. W.

    1999-01-01

    Pretreatment methods were used to improve neurofilament immunostaining in corneas from embryonic day 16 Japanese quail corneas that had been stored in fixative solution for several months. A sequential combination of the following three pretreatments: brief microwave heating in saline, followed by extraction with sodium dodecyl sulfate (SDS) at 37 degrees C, followed by digestion with hyaluronidase at 37 degrees C, produced significantly increased antibody staining of corneal neurofilament proteins, compared with embryonic corneas subjected to no prior pretreatments or to single or two-step protocols. After applying the sequence of all three pretreatments, darkest nerve staining and increased numbers of fine branches were observed, together with lower background staining. Thus, the result of applying the three-step pretreatment sequence is better than that of applying any of its component single pretreatments or even combinations of any two of them. These findings therefore suggest that each of these three pretreatments causes a unique effect, beneficial to immunostaining of neurofilament proteins, and that their individual effects are independent and additive. In addition to embryonic corneas, the three-step procedure also may be useful for immunostaining of nerves in other very delicate, highly-hydrated tissues containing an abundance of extracellular matrix.

  20. Bacterial cellulose and bacterial cellulose/polycaprolactone composite as tissue substitutes in rabbits' cornea

    Directory of Open Access Journals (Sweden)

    Rodrigo V. Sepúlveda

    Full Text Available ABSTRACT: In order to test the performance of bacterial cellulose/polycaprolactone composite (BC/PCL and pure bacterial cellulose (BC as tissue substitutes in rabbits' cornea, a superficial ulcer containing 5mm in diameter and 0.2mm deep was made in the right cornea of 36 rabbits, then a interlayer pocket was created from the basis of this ulcer. Twelve rabbits received BC/PCL membrane and 12 were treated with BC membranes, both membranes with 8mm in diameter. The remaining rabbits received no membrane constituting the control group. The animals were clinically followed up for 45 days. Three animals of each group were euthanized at three, seven, 21, and 45 days after implantation for histological examination of the cornea along with the implant. Clinical observation revealed signs of moderate inflammatory process, decreasing from day 20th in the implanted groups. Histology showed absence of epithelium on the membranes, fibroplasia close to the implants, lymph inflammatory infiltrate with giant cells, collagen disorganization, with a predominance of immature collagen fibers in both groups with implants. Although inflammatory response is acceptable, the membranes used does not satisfactorily played the role of tissue substitute for the cornea during the study period.

  1. Factors influencing the contamination rate of human organ-cultured corneas.

    Science.gov (United States)

    Röck, Daniel; Wude, Johanna; Bartz-Schmidt, Karl U; Yoeruek, Efdal; Thaler, Sebastian; Röck, Tobias

    2017-03-21

    To assess the influence of donor, environment and storage factors on the contamination rate of organ-cultured corneas, to consider the microbiological species causing corneal contamination and to investigate the corresponding sensitivities. Data from 1340 consecutive donor corneas were analysed retrospectively. Logistic regression analysis was used to assess the influence of different factors on the contamination rate of organ-cultured corneas for transplantation. The mean annual contamination rate was 1.8 ± 0.4% (range: 1.3-2.1%); 50% contaminations were of fungal origin with exclusively Candida species, and 50% contaminations were of bacterial origin with Staphylococcus species being predominant. The cause of donor death including infection and multiple organ dysfunction syndrome increased the risk of bacterial or fungal contamination during organ culture (p = 0.007 and p = 0.014, respectively). Differentiating between septic and aseptic donors showed an increased risk of contamination for septic donors (p = 0.0020). Mean monthly temperature including warmer months increased the risk of contamination significantly (p = 0.0031). Sex, donor age, death to enucleation, death to corneoscleral disc excision and storage time did not increase the risk of contamination significantly. The genesis of microbial contamination in organ-cultured donor corneas seems to be multifactorial. The main source of fungal or bacterial contamination could be resident species from the skin flora. The rate of microbial contamination in organ-cultured donor corneas seems to be dependent on the cause of donor death and mean monthly temperature. © 2017 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  2. Impression cytology and in vivo confocal microscopy in corneas with total limbal stem cell deficiency

    Directory of Open Access Journals (Sweden)

    Aline Lütz de Araújo

    2013-10-01

    Full Text Available PURPOSES: To describe corneal changes seen on in vivo confocal microscopy in patients with total limbal stem cell deficiency and to correlate them with cytological findings. METHODS: A prospective case series including 13 eyes (8 patients with total limbal deficiency was carried out. Stem cell deficiency was diagnosed clinically and by corneal impression cytology. Confocal images of the central cornea were taken with the Heidelberg Retina Tomograph II, Rostock Corneal Module (Heidelberg Engineering, Heidelberg, Germany. RESULTS: Impression cytology of the cornea revealed conjunctival epithelial cells and goblet cells in all cases. In vivo confocal microscopy showed disruption of normal layers of the corneal epithelium in all eyes. Confocal images showed cells with characteristics of conjunctival epithelium at the cornea in 76.9% of the total. These findings on confocal microscopy were compatible to limbal stem cell deficiency. Additionally, goblet cells, squamous metaplasia, inflammatory cells and dendritic cells were observed. The sub-basal nerve plexus was not identified in any of the corneas. Corneal neovessels were observed at the epithelium and stroma. All cases showed diffuse hyper-reflective images of the stroma corresponding to opacity of the tissue. CONCLUSIONS: Limbal stem cell deficiency had been confirmed by impression cytology in all cases, and 76.9% of the cases could also be diagnosed by in vivo confocal microscopy through the conjunctival epithelial cell visualization on the corneal surface. Frequent confocal microscopy findings were abnormal cells at the cornea (conjunctival epithelial, goblet and inflammatory cells, corneal neovessels and diffuse hyper-reflection of the stroma.

  3. Assessment of anti-scarring therapies in ex vivo organ cultured rabbit corneas.

    Science.gov (United States)

    Sriram, Sriniwas; Gibson, Daniel J; Robinson, Paulette; Pi, Liya; Tuli, Sonal; Lewin, Alfred S; Schultz, Gregory

    2014-08-01

    The effects of a triple combination of siRNAs targeting key scarring genes were assessed using an ex vivo organ culture model of excimer ablated rabbit corneas. The central 6 mm diameter region of fresh rabbit globes was ablated to a depth of 155 microns with an excimer laser. Corneas were excised, cultured at the air-liquid interface in defined culture medium supplemented with transforming growth factor beta 1 (TGFB1), and treated with either 1% prednisolone acetate or with 22.5 μM cationic nanoparticles complexed with a triple combination of siRNAs (NP-siRNA) targeting TGFB1, TGFB Receptor (TGFBR2) and connective tissue growth factor (CTGF). Scar formation was measured using image analysis of digital images and levels of smooth muscle actin (SMA) were assessed in ablated region of corneas using qRT-PCR and immunostaining. Ex vivo cultured corneas developed intense haze-like scar in the wounded areas and levels of mRNAs for pro-fibrotic genes were significantly elevated 3-8 fold in wounded tissue compared to unablated corneas. Treatment with NP-siRNA or steroid significantly reduced quantitative haze levels by 55% and 68%, respectively, and reduced SMA mRNA and immunohistostaining. This ex vivo corneal culture system reproduced key molecular patterns of corneal scarring and haze formation generated in rabbits. Treatment with NP-siRNAs targeting key scarring genes or an anti-inflammatory steroid reduced corneal haze and SMA mRNA and protein. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Thermodynamic measurement after cooling the cornea with intact epithelium and lid manipulation.

    Science.gov (United States)

    de Ortueta, Diego; Magnago, Thomas; Arba-Mosquera, Samuel

    2015-01-01

    To characterize the rate of change of ocular surface temperature (OST) under lid manipulation after cooling the intact cornea with balanced salt solution (BSS). In a patient for refractive surgery, prior to the ablation, the temperature of the cornea was continuously recorded with a high speed infrared (350Hz) camera. Two millilitre of chilled BSS with a temperature of 8.6°Celsius (°C) was instilled for about 3s. Using exponential functions, the three contributions have been determined, subjacent corneal layers, environment, and chilled BSS. The mean temperature of the cornea preoperatively was 34.5°C. After applying the chilled BSS the temperature decreased about 14°C down to an OST of 20°C and the time needed afterwards to get the normal (OST) temperature of about 30°C was 40s. Due to the inserted speculum and missing blink, OST did not reach the original OST of 34.5°C and faded at about 32.5°C. According to our best fitted model, absolute value of each contributing component was 31.4°C (subjacent corneal layers), 26.8°C (environment) and 8.6°C (BSS). Applying chilled BSS to the cornea quickly reduces the temperature of the cornea with a thermal relaxation time of 3s and a amplitude decrease of 8.6°C. This together with a relaxation time of 7s for subjacent corneal layers, and 184s for environment after instillation of BSS combined with a well-controlled environment provides a period of 40s of corneal temperature below baseline, which may be of clinical benefit when applying chilled BSS immediately before or immediately after ablation. Copyright © 2014 Spanish General Council of Optometry. Published by Elsevier Espana. All rights reserved.

  5. Involvement of S100A4 in stromal fibroblasts of the regenerating cornea.

    Science.gov (United States)

    Ryan, David G; Taliana, Lavinia; Sun, Lijie; Wei, Zhi-Gang; Masur, Sandra K; Lavker, Robert M

    2003-10-01

    S100A4 is a member of the S100 family of calcium-binding proteins. Members of the S100 family have been implicated in a variety of cellular events, including growth, signaling, differentiation, and motility. It has been suggested that S100A4 modulates cell shape and motility by interacting with components of the cytoskeleton. In the present study, the distribution patterns of S100A4 were investigated in normal and regenerating mouse corneas. Rabbit cDNA libraries were prepared from cultures of corneal fibroblasts. S100A4 was identified as the most abundant message present. Expression of S100A4 in the cornea was determined using Northern blot analysis, in situ hybridization, and immunohistochemistry. Distribution patterns of S100A4 in primary corneal fibroblast cultures treated with either FGF-2/heparin or TGFbeta1 were analyzed by immunofluorescence. S100A4 mRNA was rarely detected in keratocytes or epithelial cells of the normal rabbit cornea. Likewise, S100A4 antigen was not found in normal mouse corneas. However, after removal of the corneal epithelium, fibroblasts are activated and had readily detectable S100A4 expression 6 days after wounding. In the in vitro equivalent of activated keratocytes, cultured rabbit corneal fibroblasts, S100A4 was restricted to the cytoplasm. In contrast, in cultures treated with TGFbeta1, which induces a myofibroblast phenotype, more than 90% of the cells showed a nuclear localization of S100A4. The findings show that S100A4 is expressed in the keratocyte phenotypes that appear in stromal tissue of corneas recovering from damage, the fibroblasts, and myofibroblasts. Its expression and distinct subcellular redistribution patterns suggest that S100A4 may be involved in the interconversions that occur between keratocytes, fibroblasts, and myofibroblasts during corneal wound healing.

  6. Expression of microsomal prostaglandin e synthase-1 in fibroblasts of rabbit alkali-burned corneas.

    Science.gov (United States)

    Kawamura, Aruha; Tatsuguchi, Atsushi; Ishizaki, Masamichi; Takahashi, Hiroshi; Fukuda, Yuh

    2008-12-01

    Prostaglandin E2 is related to wound healing. Three different prostaglandin E synthases have been identified: microsomal prostaglandin E synthase (mPGES)-1, mPGES-2, and cytosolic prostaglandin E synthase. This study examined mPGES-1 expression in the cornea during the reparative process that occurs after an alkali burn. mPGES-1 messenger RNA (mRNA) and protein expression levels were examined by reverse transcription-polymerase chain reaction and Western blot analysis. Localization of mPGES-1 mRNA was examined by in situ hybridization. Using immunostaining, the localization of mPGES-1, cyclooxygenase (COX)-2, and alpha-smooth muscle actin (alpha-SMA) protein was studied. Although mPGES-1 mRNA is expressed in normal cornea, after a corneal injury, a progressive increase of mPGES-1 mRNA occurs. In this study, 2-6 weeks after injury, mPGES-1 mRNA was detected in the stromal spindle cells. Western blot analysis also showed that mPGES-1 protein expression was observed in normal cornea, with an increase noted from 2 to 4 weeks after corneal injury. mPGES-1 immunoreactivity was negative in normal cornea; however, starting at 2 weeks after injury, positive staining of the stromal spindle cells was noted. Although COX-2 and alpha-SMA immunoreactivities were negative in the stroma of normal cornea, after injury, staining was observed in the stromal spindle cells. alpha-SMA-positive cells and myofibroblasts express mPGES-1 mRNA and protein, and in addition, mPGES-1 colocalized with COX-2, suggesting that myofibroblasts synthesize prostaglandin E2 and may act on and accelerate corneal wound healing.

  7. Variable depth thermal lesions in rabbit corneas using a tunable thulium fiber laser

    Science.gov (United States)

    Fried, Nathaniel M.; Noguera, Guillermo; Castro-Combs, Juan; Behrens, Ashley

    2007-02-01

    Laser-induced thermal changes in the cornea have been used clinically for refractive surgery. This study describes the creation of variable depth thermal lesions in the cornea using a tunable Thulium fiber laser. Thermal lesions were created in fresh rabbit corneas, ex vivo, at three different wavelengths (1873 nm, 1890 nm, and 1904 nm) (n=6 corneas each). All other laser parameters were kept fixed with power of 5.5 W, 25-ms exposure time, and 650-μm diameter spot, yielding a single pulse exposure of 138 mJ, and a fluence of 42 J/cm2. Optical coherence tomography (OCT) and histology were used to measure pre- and post-operative corneal thickness and lesion dimensions. OCT measurements of pre and post-operative corneal thickness and lesion depth (in microns) were: (1873 nm: 450+/-30, 801+/-95, 655+/-51), (1890 nm: 460+/-27, 618+/-70, 332+/-56), (1904 nm: 448+20, 550+/-42, 245+36), respectively. By comparison, histologic measurements were: (1873 nm: 470+25, 828+21, 540+/-31), (1890 nm: 457+/-13, 625+/-17, 350+/-43), (1904 nm: 465+/-40, 627+/-35, 239+/-23), respectively. OCT lesion depth measured 82%, 54%, and 45% of corneal thickness, compared to histologic analysis of 65%, 56%, and 38%. This is the first preliminary test of a compact and tunable Thulium fiber laser for creating variable depth thermal lesions in the cornea. The Thulium fiber laser may have potential use as a replacement for the Ho:YAG and diode lasers for thermal keratoplasty.

  8. Hydration and transparency of the rabbit cornea irradiated with UVB-doses of 0.25 J/cm(2) and 0.5 J/cm(2) compared with equivalent UVB radiation exposure reaching the human cornea from sunlight.

    Science.gov (United States)

    Cejka, Cestmír; Ardan, Taras; Sirc, Jakub; Michálek, Jiří; Beneš, Jiří; Brůnová, Blanka; Rosina, Jozef

    2011-07-01

    Exposure of the cornea to UV radiation from sunlight evokes intraocular inflammation, photokeratitis. Photokeratitis is caused by UVB radiation. It is accompanied by changes of corneal hydration and light absorption. The aim of this study was to examine the effect of two UVB doses on corneal optics in rabbits and to compare these UVB doses with the equivalent exposure of UVB radiation reaching the human cornea from sunlight. Rabbit corneas were irradiated with a daily UVB dose of 0.25 J/cm(2) or 0.5 J/cm(2) for 4 days. One day after finishing the irradiations the rabbits were sacrificed and corneal light absorption measured using our spectrophotometrical method. Corneal hydration was examined using an ultrasonic Pachymeter every experimental day before the irradiation procedure and the last day before sacrificing the animals. Changes in corneal optics appeared after the repeated exposure of the cornea to a UVB dose of 0.25 J/ cm(2) and massively increased after the repeated exposure of the cornea to a UVB dose of 0.5 J/cm(2). The first significant changes in corneal hydration appeared after a single exposure of the cornea to a UVB dose of 0.25 J/cm(2). Changes in corneal hydration appeared after the exposure of the rabbit cornea to a single UVB dose equivalent to 2.6 hours of solar UVB radiation reaching the human cornea, as measured by UVB sensors embedded in the eyes of mannequin heads facing the sun on a beach at noon in July. Repeated exposure of the rabbit cornea to the same UVB dose evoked profound changes in corneal optics. Although comparison of experimental and outdoor conditions are only approximate, the results in rabbits point to the danger for the human eye from UVB radiation when short stays in sunlight are repeated for several consecutive days without UV protection.

  9. Harnessing of corneas captured and processed for transplantation in an ocular tissue bank of North-eastern Brazil

    Directory of Open Access Journals (Sweden)

    Izaura Luzia Silvério Freire

    Full Text Available The aim of this study was to describe the harnessing of corneas captured and processed for transplantation in an ocular tissue bank in north-eastern Brazil. This was a transverse and retrospective study, with a sample group of 612 individuals whose corneas were donated and captured between January/2007 and July/2012. This study was approved by the Research Ethics Committee under number 007.0.294.000-10, and research was based on an instrument consisting of social, demographic and clinical data of the donors. Of the 1209 corneas captured, 868 were used and 341 were discarded. Of the 612 donors, the corneas of 597 (97.5% were captured from both eyes, being that 423 (70.9% of these corneas were used. Further studies are required on the reasons for discarding corneas and clarifications as to the conduct of professionals when processing corneas, considering the increase in the quantity of donors and the elevated number of discarded ocular tissue.

  10. Should antibody to hepatitis B core antigen be tested in routine screening of donor corneas for transplant?

    Science.gov (United States)

    Mattern, R M; Cavanagh, H D

    1997-03-01

    A review of the literature on transfusion-transmitted infectious diseases shows that antibody to hepatitis B core antigen (anti-HBc) is not presently viewed as helpful for hepatitis C or hepatitis non-ABC screening of blood donors. Its utility as a screen for hepatitis B or human immunodeficiency virus-1 (HIV-1) is controversial among experts. We compare relevant aspects of the screening of blood donations and the screening of cornea transplant donors to assess implications for the screening of donor corneas. We conclude that there is not sufficient evidence to warrant introducing anti-HBc as a routine screening test for cornea donors.

  11. Differential expression and processing of transforming growth factor beta induced protein (TGFBIp) in the normal human cornea during postnatal development and aging

    DEFF Research Database (Denmark)

    Karring, Henrik; Runager, Kasper; Valnickova, Zuzana

    2010-01-01

    Transforming growth factor beta induced protein (TGFBIp, also named keratoepithelin) is an extracellular matrix protein abundant in the cornea. The purpose of this study was to determine the expression and processing of TGFBIp in the normal human cornea during postnatal development and aging....... TGFBIp in corneas from individuals ranging from six months to 86 years of age was detected and quantified by immunoblotting. The level of TGFBIp in the cornea increases about 30% between 6 and 14 years of age, and adult corneas contain 0.7-0.8 microg TGFBIp per mg wet tissue. Two-dimensional (2-D...... of corneal TGFBIp suggests that TGFBIp may play a role in the postnatal development and maturation of the cornea. Furthermore, these observations may be relevant to the age at which mutant TGFBIp deposits in the cornea in those dystrophies caused by mutations in the transforming growth factor beta induced...

  12. Efficacious and safe tissue-selective controlled gene therapy approaches for the cornea.

    Science.gov (United States)

    Mohan, Rajiv R; Sinha, Sunilima; Tandon, Ashish; Gupta, Rangan; Tovey, Jonathan C K; Sharma, Ajay

    2011-04-12

    Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5), and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5×10(12) vg/ml) expressing green fluorescent protein gene (GFP) was topically applied onto normal or diseased (fibrotic or neovascularized) rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng) using micropocket assay, respectively. Slit-lamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point). Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5-treated and

  13. Efficacious and safe tissue-selective controlled gene therapy approaches for the cornea.

    Directory of Open Access Journals (Sweden)

    Rajiv R Mohan

    Full Text Available Untargeted and uncontrolled gene delivery is a major cause of gene therapy failure. This study aimed to define efficient and safe tissue-selective targeted gene therapy approaches for delivering genes into keratocytes of the cornea in vivo using a normal or diseased rabbit model. New Zealand White rabbits, adeno-associated virus serotype 5 (AAV5, and a minimally invasive hair-dryer based vector-delivery technique were used. Fifty microliters of AAV5 titer (6.5×10(12 vg/ml expressing green fluorescent protein gene (GFP was topically applied onto normal or diseased (fibrotic or neovascularized rabbit corneas for 2-minutes with a custom vector-delivery technique. Corneal fibrosis and neovascularization in rabbit eyes were induced with photorefractive keratectomy using excimer laser and VEGF (630 ng using micropocket assay, respectively. Slit-lamp biomicroscopy and immunocytochemistry were used to confirm fibrosis and neovascularization in rabbit corneas. The levels, location and duration of delivered-GFP gene expression in the rabbit stroma were measured with immunocytochemistry and/or western blotting. Slot-blot measured delivered-GFP gene copy number. Confocal microscopy performed in whole-mounts of cornea and thick corneal sections determined geometric and spatial localization of delivered-GFP in three-dimensional arrangement. AAV5 toxicity and safety were evaluated with clinical eye exam, stereomicroscopy, slit-lamp biomicroscopy, and H&E staining. A single 2-minute AAV5 topical application via custom delivery-technique efficiently and selectively transduced keratocytes in the anterior stroma of normal and diseased rabbit corneas as evident from immunocytochemistry and confocal microscopy. Transgene expression was first detected at day 3, peaked at day 7, and was maintained up to 16 weeks (longest tested time point. Clinical and slit-lamp eye examination in live rabbits and H&E staining did not reveal any significant changes between AAV5

  14. Investigation of the influence of riboflavin-UV induced crosslinking on the cornea in the experiment

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    S. I. Anisimov

    2012-01-01

    Full Text Available Purpose: Morphological examination of the efficiency of the influence of various doses of riboflavin-UV induced crosslinking on the state of the corneal stroma in experimental animals.Methods: In the work were used rabbits males breed Chinchilla mass of 1.5-2.0 kg. the experiment was conducted on 20 eyes of 10 animals, which performed the routine crosslinking. Experimental animals, depending on the power UV-laser irradiation, were divided into 4 groups: the animals of the 1 group with the minimum intensity of radiation (30 minutes, 0.27 J, animals 2 group with medium intensity of radiation (15 minutes, 0.34 J, animals 3 groups with high intensity of radiation (30 minutes, 0.34 J, the control group 4 (without UV-radiation. Date of dynamic observation of the experimental animals was 5 days, after which the animals were taken out of the experiment. Morphological investigations were carried out by means of light and electron microscopy.Results: In groups of experimental animals with the impact of riboflavin UV-radiation in the stroma of the cornea were found the appearance of the areas of cross-stitched collagen fibers and fibrils. In the zone of the crosslinking were found activated keratoblasts.Near the membranes of these cells the contents of the vacuoles are released and filaments finish building of the collagen fibers. the epithelium of the corneas of all experimental animals recovered fully, with no morphological signs of endothelial damage has been found. Electron-microscopic investigation of stroma of corneas of the experimental animals of the control group after the experiment showed the presence of keratocytes in an inactive form and collagen fibers of stroma, packed in the form of plates or beams with a characteristic orientation.Conclusion: Studies have shown that UV-irradiation of the cornea leads to the appearance of linking between the fibers of collagen and actively synthesizing cells in the stroma of the cornea, which points to a

  15. Investigation of the influence of riboflavin-UV induced crosslinking on the cornea in the experiment

    Directory of Open Access Journals (Sweden)

    S. I. Anisimov

    2014-07-01

    Full Text Available Purpose: Morphological examination of the efficiency of the influence of various doses of riboflavin-UV induced crosslinking on the state of the corneal stroma in experimental animals.Methods: In the work were used rabbits males breed Chinchilla mass of 1.5-2.0 kg. the experiment was conducted on 20 eyes of 10 animals, which performed the routine crosslinking. Experimental animals, depending on the power UV-laser irradiation, were divided into 4 groups: the animals of the 1 group with the minimum intensity of radiation (30 minutes, 0.27 J, animals 2 group with medium intensity of radiation (15 minutes, 0.34 J, animals 3 groups with high intensity of radiation (30 minutes, 0.34 J, the control group 4 (without UV-radiation. Date of dynamic observation of the experimental animals was 5 days, after which the animals were taken out of the experiment. Morphological investigations were carried out by means of light and electron microscopy.Results: In groups of experimental animals with the impact of riboflavin UV-radiation in the stroma of the cornea were found the appearance of the areas of cross-stitched collagen fibers and fibrils. In the zone of the crosslinking were found activated keratoblasts.Near the membranes of these cells the contents of the vacuoles are released and filaments finish building of the collagen fibers. the epithelium of the corneas of all experimental animals recovered fully, with no morphological signs of endothelial damage has been found. Electron-microscopic investigation of stroma of corneas of the experimental animals of the control group after the experiment showed the presence of keratocytes in an inactive form and collagen fibers of stroma, packed in the form of plates or beams with a characteristic orientation.Conclusion: Studies have shown that UV-irradiation of the cornea leads to the appearance of linking between the fibers of collagen and actively synthesizing cells in the stroma of the cornea, which points to a

  16. Measurement of quantitative viscoelasticity of bovine corneas based on lamb wave dispersion properties.

    Science.gov (United States)

    Zhang, Xinyu; Yin, Yin; Guo, Yanrong; Fan, Ning; Lin, Haoming; Liu, Fulong; Diao, Xianfen; Dong, Changfeng; Chen, Xin; Wang, Tianfu; Chen, Siping

    2015-05-01

    The viscoelastic properties of the human cornea can provide valuable information for clinical applications such as the early detection of corneal diseases, better management of corneal surgery and treatment and more accurate measurement of intra-ocular pressure. However, few techniques are capable of quantitatively and non-destructively assessing corneal biomechanics in vivo. The cornea can be regarded as a thin plate in which the vibration induced by an external vibrator propagates as a Lamb wave, the properties of which depend on the thickness and biomechanics of the tissue. In this study, pulses of ultrasound radiation force with a repetition frequency of 100 or 200 Hz were applied to the apex of corneas, and the linear-array transducer of a SonixRP system was used to track the tissue motion in the radial direction. Shear elasticity and viscosity were estimated from the phase velocities of the A0 Lamb waves. To assess the effectiveness of the method, some of the corneas were subjected to collagen cross-linking treatment, and the changes in mechanical properties were validated with a tensile test. The results indicated that the shear modulus was 137 ± 37 kPa and the shear viscosity was 3.01 ± 2.45 mPa · s for the group of untreated corneas and 1145 ± 267 kPa and was 0.16 ± 0.11 mPa · s for the treated group, respectively, implying a significant increase in elasticity and a significant decrease in viscosity after collagen cross-linking treatment. This result is in agreement with the results of the mechanical tensile test and with reports in the literature. This initial investigation illustrated the ability of this ultrasound-based method, which uses the velocity dispersion of low-frequency A0 Lamb waves, to quantitatively assess both the elasticity and viscosity of corneas. Future studies could discover ways to optimize this system and to determine the feasibility of using this method in clinical situations.

  17. Characterizing the effects of VPA, VC and RCCS on rabbit keratocytes onto decellularized bovine cornea.

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    Ying Dai

    Full Text Available To investigate the morphological and growth characteristics of rabbit keratocytes when cultured on decellularized cornea under simulate microgravity (SMG rotary cell culture system (RCCS and static culture or in plastic culture supplemented with small molecules of valproic acid (VPA and vitamin C (VC. Bovine corneas were firstly decellularized with Triton X-100 and NH(4OH and through short-term freezing process. Then cell count kit-8 (CCK-8 and flow cytometry were used to test the effects of VPA and VC on the proliferation, cell cycle and apoptosis of rabbit keratocytes. Hematoxylin-eosin (H&E staining and scanning electron microscopy (SEM imaging showed that cells were eliminated in the decellularized bovine corneas. The proliferation of cultured keratocytes was promoted by VPA and VC in the cell proliferation assay. VPA and VC moderately decreased the number of apoptotic cells and obviously promoted cell-cycle entrance of keratocytes. Rabbit keratocytes in plastic displayed spindle shape and rare interconnected with or without VPA and VC. Cells revealed dendritic morphology and reticular cellular connections when cultured on the carriers of decellularized corneas supplemented with VPA and VC even in the presence of 10% fetal bovine serum (FBS. When cultured in RCCS supplemented with VPA, VC and 10% FBS, keratocytes displayed round shape with many prominences and were more prone to grow into the pores of carriers with aggregation. Reverse transcription-polymerase chain reaction (RT-PCR analysis proved that the keratocytes cultured on decellularized bovine cornea under SMG with VPA and VC expressed keratocan and lumican. Keratocytes cultured on plastic expressed lumican but not keratocan. Immunofluorescence identification revealed that cells in all groups were positively immunostained for vimentin. Keratocytes on decellularized bovine cornea under SMG or in static culture were positively immunostained for keratocan and lumican. Thus, we

  18. Physicochemical properties of biodegradable polyvinyl alcohol-agar films from the red algae Hydropuntia cornea.

    Science.gov (United States)

    Madera-Santana, Tomás J; Robledo, Daniel; Freile-Pelegrín, Yolanda

    2011-08-01

    Agar obtained from the red alga Hydropuntia cornea was blended with polyvinyl alcohol (PVOH) in order to produce biodegradable films. In this study, we compare the properties of biopolymeric films formulated with agars extracted from H. cornea collected at different seasons (rainy and dry) in the Gulf of Mexico coast and PVOH as synthetic matrix. The films were prepared at different agar contents (0%, 25%, 50%, 75%, and 100%) and their optical, mechanical, thermal, and morphological properties analyzed. The tensile strength of PVOH-agar films increased when agar content was augmented. The formulation with 50% agar from rainy season (RS) had a significant higher tensile strength when compared to those from dry season (DS; p biodegradable packaging industry.

  19. Photodynamic therapy (ALA-PDT) in the treatment of pathological states of the cornea

    Science.gov (United States)

    Switka-Wieclawska, Iwona; Kecik, Tadeusz; Kwasny, Miroslaw; Graczyk, Alfreda

    2003-10-01

    Each year an increasing amount of research is published on the use of photodynamic therapy in medicine. The most recent research has focused mostly on the use of photosensitizer called vertoporphyrin (Visudyne) is the treatment of subretinal neovascularization in age-related macular degeneration (AMD) or myopia, following a substantial amount of ophthalmology research mostly experimental on the application of the method in diagnosis and treatment of some eye tumors. In the Department of Ophthalmology of Polish Medical University in Warsaw, PDT was used as supplementary method in a selected group of patients with chronic virus ulcer of the cornea and keratopathies. During the treatment 5-aminolevulinic acid (5-ALA) was applied in ointment form as a photosensitizer activated with light wave of 633 nm. It appears, on the basis of the results obtained, that photodynamic therapy (ALA-PDT) may become in the future a valuable supplement to the methods being used at the present treating pathological states of the cornea.

  20. Tectonic deep anterior lamellar keratoplasty in impending corneal perforation using cryopreserved cornea.

    Science.gov (United States)

    Jang, Ji Hye; Chang, Sung Dong

    2011-04-01

    We report a case of tectonic corneal transplantation for impending corneal perforation to preserve anatomic integrity using cryopreserved donor tissue. An 82-year-old woman exhibiting impending corneal perforation suffered from moderate ocular pain in the left eye for one week. After abnormal tissues around the impending perforation area were carefully peeled away using a Crescent blade and Vannas scissors, the patient received tectonic deep anterior lamellar keratoplasty using a cryopreserved cornea stored in Optisol GS® solution at -70℃ for four weeks. At six months after surgery, the cornea remained transparent and restored the normal corneal thickness. There were no complications such as corneal haze or scars, graft rejection, recurrent corneal ulcer, and postoperative rise of intraocular pressure. Cryopreserved donor lamellar tissue is an effective substitute in emergency tectonic lamellar keratoplasty, such as impending corneal perforation and severe necrotic corneal keratitis.

  1. A new optical system for 3-dimensional mapping of the cornea

    Science.gov (United States)

    Franco, Sandra; Almeida, José B.

    2007-07-01

    In this work the authors present an optical corneal tomographer that uses two Scheimpflug cameras attached to an innovative illumination system that allows a rotary scanning of the entire cornea. The measurements are made from corneal optical sections obtained by illumination with a collimated beam expanded in a fan by a small cylindrical lens. This lens is provided with motor driven rotation in order to perform automated rotary scan of the whole cornea. The authors expect to achieve a scanning speed that will allow producing complete tomography maps without consideration of eye movements. Two Scheimpflug cameras are used to capture the images of the optical sections. With this system it is possible to obtain 3-D representation of the corneal thickness as well as corneal topography. Maps of the corneal thickness and elevation maps are shown. As Scheimpflug cameras are used, it is expected to obtained data from the lens too.

  2. Collagens and proteoglycans of the cornea: importance in transparency and visual disorders.

    Science.gov (United States)

    Massoudi, Dawiyat; Malecaze, Francois; Galiacy, Stephane D

    2016-02-01

    The cornea represents the external part of the eye and consists of an epithelium, a stroma and an endothelium. Due to its curvature and transparency this structure makes up approximately 70% of the total refractive power of the eye. This function is partly made possible by the particular organization of the collagen extracellular matrix contained in the corneal stroma that allows a constant refractive power. The maintenance of such an organization involves other molecules such as type V collagen, FACITs (fibril-associated collagens with interrupted triple helices) and SLRPs (small leucine-rich proteoglycans). These components play crucial roles in the preservation of the correct organization and function of the cornea since their absence or modification leads to abnormalities such as corneal opacities. Thus, the aim of this review is to describe the different corneal collagens and proteoglycans by highlighting their importance in corneal transparency as well as their implication in corneal visual disorders.

  3. Sensitivity and rapidity of blood culture bottles in the detection of cornea organ culture media contamination by bacteria and fungi

    OpenAIRE

    Thuret, G; Carricajo, A.; Chiquet, C.; Vautrin, A C; Celle, N; Boureille, M; Acquart, S; Aubert, G.; Maugery, J; Gain, P.

    2002-01-01

    Aims: To test the bactericidal activity of standard organ culture medium, and to compare the sensitivity and rapidity of blood culture bottles with conventional microbiological methods for detection of bacteria and fungi inoculated in a standard cornea organ culture medium.

  4. Keratoconus Screening Indices and Their Diagnostic Ability to Distinguish Normal From Ectatic Corneas.

    Science.gov (United States)

    Shetty, Rohit; Rao, Harsha; Khamar, Pooja; Sainani, Kanchan; Vunnava, Krishnapoojita; Jayadev, Chaitra; Kaweri, Luci

    2017-09-01

    To compare the diagnostic ability of 3 Scheimpflug devices in differentiating normal from ectatic corneas. Comparison of diagnostic instrument accuracy. This study included 42 normal, 37 subclinical keratoconic, and 51 keratoconic eyes seen in a tertiary eye care institute. Keratoconus screening indices were evaluated using the Pentacam (Oculus, Wetzlar, Germany), Galilei (Ziemer, Biel, Switzerland), and Sirius (Costruzione Strumenti Oftalmici, Florence, Italy). Sensitivity, specificity, and area under receiver operating characteristic curve (AUC) were calculated. Highest sensitivity (100%) to diagnose keratoconus was seen for 6 parameters on Pentacam and 1 on Galilei. None of the indices in Sirius reached 100% sensitivity. For subclinical keratoconus, the highest sensitivity (100%) was seen for 2 parameters on Pentacam but for none of them on Galilei and Sirius. All parameters were strong enough to differentiate keratoconus (AUC > 0.9). On comparing the best parameters of all 3 machines, the AUC of the Belin/Ambrosio enhanced ectasia total derivation (BAD-D) and the inferior-superior value (ISV) of Pentacam were statistically similar to that of the keratoconus prediction index (KPI) and keratoconus probability (Kprob) of Galilei (P = .27) and 4.5 mm root mean square per unit area (RMS/A) back of Sirius (P = .55). When differentiating subclinical from normal corneas, BAD-D was similar to the surface regularity index (SRI) of Galilei (P = .78) but was significantly greater than the 8 mm RMS/A back of Sirius (P = .002). Keratoconus indices measured by all 3 machines can effectively differentiate keratoconus from normal corneas. However, new cutoff values might be needed to differentiate subclinical from normal corneas. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. New insight into the shortening of the collagen fibril D-period in human cornea.

    Science.gov (United States)

    Jastrzebska, Maria; Tarnawska, Dorota; Wrzalik, Roman; Chrobak, Artur; Grelowski, Michal; Wylegala, Edward; Zygadlo, Dorota; Ratuszna, Alicja

    2017-02-01

    Collagen fibrils type I display a typical banding pattern, so-called D-periodicity, of about 67 nm, when visualized by atomic force or electron microscopy imaging. Herein we report on a significant shortening of the D-period for human corneal collagen fibrils type I (21 ± 4 nm) upon air-drying, whereas no changes in the D-period were observed for human scleral collagen fibrils type I (64 ± 4 nm) measured under the same experimental conditions as the cornea. It was also found that for the corneal stroma fixed with glutaraldehyde and air-dried, the collagen fibrils show the commonly accepted D-period of 61 ± 8 nm. We used the atomic force microscopy method to image collagen fibrils type I present in the middle layers of human cornea and sclera. The water content in the cornea and sclera samples was varying in the range of .066-.085. Calculations of the D-period using the theoretical model of the fibril and the FFT approach allowed to reveal the possible molecular mechanism of the D-period shortening in the corneal collagen fibrils upon drying. It was found that both the decrease in the shift and the simultaneous reduction in the distance between tropocollagen molecules can be responsible for the experimentally observed effect. We also hypothesize that collagen type V, which co-assembles with collagen type I into heterotypic fibrils in cornea, could be involved in the observed shortening of the corneal D-period.

  6. Atmospheric-Pressure Cold Plasma Induces Transcriptional Changes in Ex Vivo Human Corneas.

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    Umberto Rosani

    Full Text Available Atmospheric pressure cold plasma (APCP might be considered a novel tool for tissue disinfection in medicine since the active chemical species produced by low plasma doses, generated by ionizing helium gas in air, induces reactive oxygen species (ROS that kill microorganisms without substantially affecting human cells.In this study, we evaluated morphological and functional changes in human corneas exposed for 2 minutes (min to APCP and tested if the antioxidant n-acetyl l-cysteine (NAC was able to inhibit or prevent damage and cell death.Immunohistochemistry and western blotting analyses of corneal tissues collected at 6 hours (h post-APCP treatment demonstrated no morphological tissue changes, but a transient increased expression of OGG1 glycosylase that returned to control levels in 24 h. Transcriptome sequencing and quantitative real time PCR performed on different corneas revealed in the treated corneas many differentially expressed genes: namely, 256 and 304 genes showing expression changes greater than ± 2 folds in the absence and presence of NAC, respectively. At 6 h post-treatment, the most over-expressed gene categories suggested an active or enhanced cell functioning, with only a minority of genes specifically concerning oxidative DNA damage and repair showing slight over-expression values (<2 folds. Moreover, time-related expression analysis of eight genes up-regulated in the APCP-treated corneas overall demonstrated the return to control expression levels after 24 h.These findings of transient oxidative stress accompanied by wide-range transcriptome adjustments support the further development of APCP as an ocular disinfectant.

  7. Inflammation Modulatory Protein TSG-6 for Chemical Injuries to the Cornea

    Science.gov (United States)

    2015-10-01

    protein TNF -stimulating gene 6 (TSG-6). TSG-6 may modulate the excessive inflammatory response that exacerbates the injury to the cornea caused by...period. The inflammatory response as measured by biochemical markers correlated with concentration of NAOH applied and began within 2 hours of injury...Goal – Establish the appropriate conditions for testing TSG-6 Determine timing and patterns of cellular and cytokine inflammatory responses as a

  8. A Cornea Substitute Derived from Fish Scale: 6-Month Followup on Rabbit Model

    OpenAIRE

    Fei Yuan; Liyan Wang; Chien-Chen Lin; Cheng-Hung Chou; Lei Li

    2014-01-01

    A fish scale-derived cornea substitute (Biocornea) is proposed as an alternative for human donor corneal tissue. We adopt a regenerative medicine approach to design a primary alternative to the use of fish scale for restoring sight by corneal replacement. Biocornea with corneal multilayer arrangement collagen was implanted to rabbits by pocket implantation. Our study demonstrated the safety and detailed morphologic and physiologic results from the 6 months of followup of rabbit model. In the ...

  9. Pathogenic strains of Acanthamoeba are recognized by TLR4 and initiated inflammatory responses in the cornea.

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    Hassan Alizadeh

    Full Text Available Free-living amoebae of the Acanthamoeba species are the causative agent of Acanthamoeba keratitis (AK, a sight-threatening corneal infection that causes severe pain and a characteristic ring-shaped corneal infiltrate. Innate immune responses play an important role in resistance against AK. The aim of this study is to determine if Toll-like receptors (TLRs on corneal epithelial cells are activated by Acanthamoeba, leading to initiation of inflammatory responses in the cornea. Human corneal epithelial (HCE cells constitutively expressed TLR1, TLR2, TLR3, TLR4, and TLR9 mRNA, and A. castellanii upregulated TLR4 transcription. Expression of TLR1, TLR2, TLR3, and TLR9 was unchanged when HCE cells were exposed to A. castellanii. IL-8 mRNA expression was upregulated in HCE cells exposed to A. castellanii. A. castellanii and lipopolysaccharide (LPS induced significant IL-8 production by HCE cells as measured by ELISA. The percentage of total cells positive for TLR4 was higher in A. castellanii stimulated HCE cells compared to unstimulated HCE cells. A. castellanii induced upregulation of IL-8 in TLR4 expressing human embryonic kidney (HEK-293 cells, but not TLR3 expressing HEK-293 cells. TLR4 neutralizing antibody inhibited A. castellanii-induced IL-8 by HCE and HEK-293 cells. Clinical strains but not soil strains of Acanthamoeba activated TLR4 expression in Chinese hamster corneas in vivo and in vitro. Clinical isolates but not soil isolates of Acanthamoeba induced significant (P< 0.05 CXCL2 production in Chinese hamster corneas 3 and 7 days after infection, which coincided with increased inflammatory cells in the corneas. Results suggest that pathogenic species of Acanthamoeba activate TLR4 and induce production of CXCL2 in the Chinese hamster model of AK. TLR4 may be a potential target in the development of novel treatment strategies in Acanthamoeba and other microbial infections that activate TLR4 in corneal cells.

  10. Proteoglycan biosynthesis by human corneas from patients with types 1 and 2 macular corneal dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Midura, R.J.; Hascall, V.C.; MacCallum, D.K.; Meyer, R.F.; Thonar, E.J.; Hassell, J.R.; Smith, C.F.; Klintworth, G.K. (National Institute of Dental Research, Bethesda, MD (USA))

    1990-09-15

    Corneal buttons were obtained from patients with types 1 and 2 macular corneal dystrophy (MCD) and from control patients with Fuchs' dystrophy or keratoconus. Buttons were incubated for 20 h in the presence of (3H)glucosamine or (2-3H)mannose. Radiolabeled proteoglycans and lactosaminoglycan-glycoproteins (L-GPs) were purified using chromatography on Q-Sepharose, Superose 6, and octyl-Sepharose. They were identified using chondroitinase ABC, keratanase or endo-beta-galactosidase digestion, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis or Superose 6 chromatography. This study confirms previous reports that type 1 MCD corneas synthesize a normal dermatan sulfate-proteoglycan (DS-PG) and an abnormal keratan sulfate-proteoglycan (KS-PG). The data indicate that typ 1 MCD corneas synthesize L-GP instead of KS-PG. This L-GP has a core protein of similar hydrophobicity (elution from octyl-Sepharose) and nearly similar mass (42 kDa) as the core protein of the KS-PG. It has identical glycoconjugates as those of the KS-PG except that they lack sulfate. Thus, type 1 MCD fails to synthesize keratan sulfate as a result of a defect in a sulfotransferase specific for sulfating lactosaminoglycans. Further, proteoglycans synthesized by a cornea from a patient with type 2 MCD were studied. This cornea synthesized a normal ratio of KS-PG to DS-PG although net synthesis of proteoglycans was approximately 30% below normal. The KS-PG appeared normal whereas the DS-PG had dermatan sulfate chains that were approximately 40% shorter than normal.

  11. Demonstration of cornea Dua's layer at a deep anterior lamellar keratoplasty surgery

    OpenAIRE

    Yusuf Kocluk; Ayse Burcu; Emine Alyamac Sukgen

    2016-01-01

    The authors aimed to present a deep anterior lamellar keratoplasty (DALK) surgery case with mixed type bubble demonstrating Dua′s layer (DL). This was a reported case of DALK surgery. The authors encountered cornea DL structure at DALK surgery while cleaning the remaining stromal pieces. We also observed perforation in the central part of DL. However, DALK surgery could be completed. It is possible to encounter DL in a DALK surgery performed with mixed type big-bubble.

  12. Demonstration of cornea Dua′s layer at a deep anterior lamellar keratoplasty surgery

    Directory of Open Access Journals (Sweden)

    Yusuf Kocluk

    2016-01-01

    Full Text Available The authors aimed to present a deep anterior lamellar keratoplasty (DALK surgery case with mixed type bubble demonstrating Dua′s layer (DL. This was a reported case of DALK surgery. The authors encountered cornea DL structure at DALK surgery while cleaning the remaining stromal pieces. We also observed perforation in the central part of DL. However, DALK surgery could be completed. It is possible to encounter DL in a DALK surgery performed with mixed type big-bubble.

  13. Synthesis of type III collagen by fibroblasts from the embryonic chick cornea

    OpenAIRE

    1980-01-01

    Synthesis of collagen types I, II, III, and IV in cells from the embryonic chick cornea was studied using specific antibodies and immunofluorescence. Synthesis of radioactively labeled collagen types I and III was followed by fluorographic detection of cyanogen bromide peptides on polyacrylamide slab gels and by carboxymethylcellulose chromatography followed by disc gel electrophoresis. Type III collagen had been detected previously by indirect immunofluorescence in the corneal epithelial cel...

  14. Occurrence of viral DNA in paired samples of corneal rim and cornea preservation fluid.

    Science.gov (United States)

    Broniek, G; Langwińska-Wośko, E; Sybilska, M; Szaflik, J P; Przybylski, M; Wróblewska, M

    2017-04-01

    Corneal transplants have one of the highest success rates among all transplantological procedures. Corneas intended for transplantation are stored in a preservation fluid, which is then tested for bacterial and fungal infections. Among all analyses of infectious complications following corneal transplants, infections caused by bacteria or fungi are the most prominent. Surprisingly, however, apart from a few publications, there is a lack of data regarding the occurrence of viruses in donor corneas and the risk of transmitting these to their recipients. The intention of this research was therefore to determine the frequency with which human herpesvirus 1 (HHV-1), human herpesvirus 2 (HHV-2), and human adenovirus (HAdV) occur in transplanted corneal tissue, as well as in samples of preservation fluid. The study comprised 57 paired samples, with each pair consisting of a fragment of the corneal tissue remaining after its trepanation for transplantation surgery and a sample of corneal preservation fluid. Sample pairs were all tested for the presence of the DNA of three viruses (HHV-1, HHV-2, and HAdV) using real time PCR technique. Viral DNA was found in three of the tested corneas-HHV-1 DNA in one paired sample (1.8%) and adenovirus DNA in two single samples (3.5%). We postulate that virological testing of corneas for transplantation should be considered, particularly in the case of donors with increased risk factors for herpesvirus and adenovirus reactivation. J. Med. Virol. 89:732-736, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  15. Safety of cornea and iris in ocular surgery with 355-nm lasers.

    Science.gov (United States)

    Wang, Jenny; Chung, Jae Lim; Schuele, Georg; Vankov, Alexander; Dalal, Roopa; Wiltberger, Michael; Palanker, Daniel

    2015-09-01

    A recent study showed that 355-nm nanosecond lasers cut cornea with similar precision to infrared femtosecond lasers. However, use of ultraviolet wavelength requires precise assessment of ocular safety to determine the range of possible ophthalmic applications. In this study, the 355-nm nanosecond laser was evaluated for corneal and iris damage in rabbit, porcine, and human donor eyes as determined by minimum visible lesion (MVL) observation, live/dead staining of the endothelium, and apoptosis assay. Single-pulse damage to the iris was evaluated on porcine eyes using live/dead staining. In live rabbits, the cumulative median effective dose (ED50) for corneal damage was 231 J/cm2, as seen by lesion observation. Appearance of endothelial damage in live/dead staining or apoptosis occurred at higher radiant exposure of 287 J/cm2. On enucleated rabbit and porcine corneas, ED50 was 87 and 52 J/cm2, respectively, by MVL, and 241 and 160 J/cm2 for endothelial damage. In human eyes, ED50 for MVL was 110 J/cm2 and endothelial damage at 453 J/cm2. Single-pulse iris damage occurred at ED 50 of 208 mJ/cm2. These values determine the energy permitted for surgical patterns and can guide development of ophthalmic laser systems. Lower damage threshold in corneas of enucleated eyes versus live rabbits is noted for future safety evaluation.

  16. Surface modification of silicone rubber membrane by plasma induced graft copolymerization as artificial cornea.

    Science.gov (United States)

    Hsiue, G H; Lee, S D; Chang, P C

    1996-11-01

    In this study a highly biocompatible polymer membrane was prepared by surface modification. An artificial cornea was also developed for clinical applications. Silicone rubber (SR) membrane was grafted with hydrophilic monomers such as 2-hydroxyethyl methacrylate (HEMA) and acrylic acid by plasma induced grafted polymerization. Surface properties of the SR were characterized using secondary ions mass spectra, Fourier transform infrared/attenuated total reflection, and element spectra for chemical analysis. The corneal epithelial (CE) cell was cultured in vitro, and penetrating keratoplasty of albino rabbit cornea (in vivo) was performed to evaluate biological properties of modified SR membranes. The ability of the CE cell to attach onto various SR membranes was observed by inverted microscopy. The proliferation of CE cell was conducted in approximately 96 h. Experimental results indicated that the attachment and growth of CE onto SR-g-pHEMA (75 micrograms/ cm2) is enhanced. The morphologies of an attached CE cell are similar to those of a primary CE cell. In the in vivo study, the depth of anterior chamber was maintained 2 weeks after penetrating keratoplasty was performed with a SR grafted with pHEMA (210 micrograms/cm2). This phenomenon displayed a high biocompatibility of modified SR membrane with the CE cell. Furthermore, results in this study provide a valuable reference for application of the modified SR for an artificial cornea.

  17. Resazurin metabolism assay is a new sensitive alternative test in isolated pig cornea.

    Science.gov (United States)

    Perrot, Sébastien; Dutertre-Catella, Hélène; Martin, Chantal; Rat, Patrice; Warnet, Jean-Michel

    2003-03-01

    The main object of our study was to investigate whether the resazurin metabolism assay is a sensitive surfactant and alcohol toxicity test in isolated pig cornea and to compare this recently developed fluorometric assay with the data collected in the eye irritation reference chemical data bank. Resazurin is a substrate that changes color in response to metabolic activity. Isolated pig corneas were immersed for 10 min in surfactants and alcohol irritant solutions. After incubation, resorufin fluorescence was read and corneal viability was assessed. This corneal viability was compared with the maximal modified average score published in the report of ECETOC. This assay highlighted different concentration-dependent irritation potentials of the three surfactants tested, and the same results were obtained with corneas treated with the alcohols. We observed that the degree of surfactant- and alcohol-induced decrease in corneal viability, using the resazurin reduction test, was correlated with the in vivo irritancy measurements as determined by the Draize test and scored with the Modified Maximum Average Score (MMAS). This assay allowed us to classify the ocular irritancy of the tested surfactants and alcohols in the same ranking order as the Draize classification. Corneal viability measurement can be used as a potential alternative for the toxicological assessment of surfactants and alcohols. The nontoxic, nonradioactive resazurin metabolism assay allows rapid assessment of many samples with simple equipment and at reduced cost for continuous monitoring of corneal viability. This assay seems to be suitable as a toxicological screening test for eye irritation determination.

  18. Temperature limitation may explain the containment of the trophozoites in the cornea during Acanthamoeba castellanii keratitis.

    Science.gov (United States)

    Nielsen, Mattias Kiel; Nielsen, Kim; Hjortdal, Jesper; Sørensen, Uffe B Skov

    2014-12-01

    Acanthamoeba keratitis is a serious sight-threatening disease. The relatively low temperature of the cornea may explain why amoebic infections usually are localized in this tissue and rarely spread to other parts of the eye. In this study, the growth rate of the amoeba Acanthamoeba castellanii was examined at different temperatures. The aim was to establish the optimal growth temperature for A. castellanii and to examine the growth within the vicinity of the core body temperature. The growth rates of four clinical and two environmental strains of A. castellanii were estimated at different temperatures, and temperature limitations for the trophozoite stage was established. Movements influenced by temperature gradients were monitored for two clinical strains of A. castellanii. The highest growth rate for each of the six amoebic strains tested was found to be close to 32 °C. The growth of the trophozoites of all examined strains was greatly reduced or completely halted at temperatures above 36 °C and encysted at the elevated temperature. Thus, the optimal growth temperature for the four strains of A. castellanii is close to the surface temperature of the human cornea, while the higher body core-temperature induced encysting of the amoebae. This may explain why most amoebic eye infections are confined to the cornea.

  19. Blast Wave Dynamics at the Cornea as a Function of Eye Protection Form and Fit.

    Science.gov (United States)

    Williams, Steven T; Harding, Thomas H; Statz, J Keegan; Martin, John S

    2017-03-01

    A shock tube and anthropomorphic headforms were used to investigate eye protection form and fit using eyewear on the Authorized Protective Eyewear List in primary ocular blast trauma experiments. Time pressure recordings were obtained from highly linear pressure sensors mounted at the cornea of instrumented headforms of different sizes. A custom shock tube produced highly reliable shock waves and pressure recordings were collected as a function of shock wave orientation and protective eyewear. Eyewear protection coefficients were calculated as a function of a new metric of eyewear fit. In general, better protection was correlated with smaller gaps between the eyewear and face. For oblique angles, most spectacles actually potentiated the blast wave by creating higher peak pressures at the cornea. Installing foam around the perimeter of the spectacle lens to close the gap between the lens and face resulted in significantly lower pressure at the cornea. In conclusion, current eye protection, which was designed to reduce secondary and tertiary blast injuries, provides insufficient protection against primary blast injury. Reprint & Copyright © 2017 Association of Military Surgeons of the U.S.

  20. Femtosecond laser cutting of human corneas for the subbasal nerve plexus evaluation.

    Science.gov (United States)

    Kowtharapu, B S; Marfurt, C; Hovakimyan, M; Will, F; Richter, H; Wree, A; Stachs, O; Guthoff, R F

    2017-01-01

    Assessment of various morphological parameters of the corneal subbasal nerve plexus is a valuable method of documenting the structural and presumably functional integrity of the corneal innervation in health and disease. The aim of this work is to establish a rapid, reliable and reproducible method for visualization of the human corneal SBP using femtosecond laser cut corneal tissue sections. Trephined healthy corneal buttons were fixed and processed using TissueSurgeon-a femtosecond laser based microtome, to obtain thick tissue sections of the corneal epithelium and anterior stroma cut parallel to the ocular surface within approximately 15 min. A near infrared femtosecond laser was focused on to the cornea approximately 70-90 μm from the anterior surface to induce material separation using TissueSurgeon. The obtained corneal sections were stained following standard immunohistochemical procedures with anti-neuronal β-III tubulin antibody for visualization of the corneal nerves. Sections that contained the epithelium and approximately 20-30 μm of anterior stroma yielded excellent visualisation of the SBP with minimal optical interference from underlying stromal nerves. In conclusion, the results of this study have demonstrated that femtosecond laser cutting of the human cornea offers greater speed, ease and reliability than standard tissue preparation methods for obtaining high quality thick sections of the anterior cornea cut parallel to the ocular surface. © 2016 The Authors Journal of Microscopy © 2016 Royal Microscopical Society.

  1. A Cornea Substitute Derived from Fish Scale: 6-Month Followup on Rabbit Model

    Directory of Open Access Journals (Sweden)

    Fei Yuan

    2014-01-01

    Full Text Available A fish scale-derived cornea substitute (Biocornea is proposed as an alternative for human donor corneal tissue. We adopt a regenerative medicine approach to design a primary alternative to the use of fish scale for restoring sight by corneal replacement. Biocornea with corneal multilayer arrangement collagen was implanted to rabbits by pocket implantation. Our study demonstrated the safety and detailed morphologic and physiologic results from the 6 months of followup of rabbit model. In the peripheral Biocornea, the collagen fibrils were arranged in reticular fashion. Slit lamp examination showed that haze and an ulcer were not observed in all groups at 3 months postoperatively while all corneas with Biocornea were clear at both 3 months and 6 months postoperatively. The interface of Biocornea and stromal tissue were filled successfully and without observable immune cells at postoperative day 180. Moreover, the Biocornea was not dissolved and degenerated but remained transparent and showed no apparent fragmentation. Our study demonstrated that the Biocornea derived from fish scale as a good substitute had high biocompatibility and support function after a long-term evaluation. This revealed that the new approach of using Biocornea may yield an ideal artificial cornea substitute for long-term inlay placement.

  2. Characterization of tissue-engineered posterior corneas using second- and third-harmonic generation microscopy.

    Directory of Open Access Journals (Sweden)

    Louis Jay

    Full Text Available Three-dimensional tissues, such as the cornea, are now being engineered as substitutes for the rehabilitation of vision in patients with blinding corneal diseases. Engineering of tissues for translational purposes requires a non-invasive monitoring to control the quality of the resulting biomaterial. Unfortunately, most current methods still imply invasive steps, such as fixation and staining, to clearly observe the tissue-engineered cornea, a transparent tissue with weak natural contrast. Second- and third-harmonic generation imaging are well known to provide high-contrast, high spatial resolution images of such tissues, by taking advantage of the endogenous contrast agents of the tissue itself. In this article, we imaged tissue-engineered corneal substitutes using both harmonic microscopy and classic histopathology techniques. We demonstrate that second- and third-harmonic imaging can non-invasively provide important information regarding the quality and the integrity of these partial-thickness posterior corneal substitutes (observation of collagen network, fibroblasts and endothelial cells. These two nonlinear imaging modalities offer the new opportunity of monitoring the engineered corneas during the entire process of production.

  3. Characterization of tissue-engineered posterior corneas using second- and third-harmonic generation microscopy.

    Science.gov (United States)

    Jay, Louis; Bourget, Jean-Michel; Goyer, Benjamin; Singh, Kanwarpal; Brunette, Isabelle; Ozaki, Tsuneyuki; Proulx, Stéphanie

    2015-01-01

    Three-dimensional tissues, such as the cornea, are now being engineered as substitutes for the rehabilitation of vision in patients with blinding corneal diseases. Engineering of tissues for translational purposes requires a non-invasive monitoring to control the quality of the resulting biomaterial. Unfortunately, most current methods still imply invasive steps, such as fixation and staining, to clearly observe the tissue-engineered cornea, a transparent tissue with weak natural contrast. Second- and third-harmonic generation imaging are well known to provide high-contrast, high spatial resolution images of such tissues, by taking advantage of the endogenous contrast agents of the tissue itself. In this article, we imaged tissue-engineered corneal substitutes using both harmonic microscopy and classic histopathology techniques. We demonstrate that second- and third-harmonic imaging can non-invasively provide important information regarding the quality and the integrity of these partial-thickness posterior corneal substitutes (observation of collagen network, fibroblasts and endothelial cells). These two nonlinear imaging modalities offer the new opportunity of monitoring the engineered corneas during the entire process of production.

  4. Fractal analysis of AFM images of the surface of Bowman's membrane of the human cornea.

    Science.gov (United States)

    Ţălu, Ştefan; Stach, Sebastian; Sueiras, Vivian; Ziebarth, Noël Marysa

    2015-04-01

    The objective of this study is to further investigate the ultrastructural details of the surface of Bowman's membrane of the human cornea, using atomic force microscopy (AFM) images. One representative image acquired of Bowman's membrane of a human cornea was investigated. The three-dimensional (3-D) surface of the sample was imaged using AFM in contact mode, while the sample was completely submerged in optisol solution. Height and deflection images were acquired at multiple scan lengths using the MFP-3D AFM system software (Asylum Research, Santa Barbara, CA), based in IGOR Pro (WaveMetrics, Lake Oswego, OR). A novel approach, based on computational algorithms for fractal analysis of surfaces applied for AFM data, was utilized to analyze the surface structure. The surfaces revealed a fractal structure at the nanometer scale. The fractal dimension, D, provided quantitative values that characterize the scale properties of surface geometry. Detailed characterization of the surface topography was obtained using statistical parameters, in accordance with ISO 25178-2: 2012. Results obtained by fractal analysis confirm the relationship between the value of the fractal dimension and the statistical surface roughness parameters. The surface structure of Bowman's membrane of the human cornea is complex. The analyzed AFM images confirm a fractal nature of the surface, which is not taken into account by classical surface statistical parameters. Surface fractal dimension could be useful in ophthalmology to quantify corneal architectural changes associated with different disease states to further our understanding of disease evolution.

  5. Ophthoselfie: Detailed Self-imaging of Cornea and Anterior Segment by Smartphone

    Directory of Open Access Journals (Sweden)

    Abdullah Kaya

    2017-06-01

    Full Text Available Objectives: To describe the ophthoselfie, a method by which everyone can take detailed self-images of the cornea and anterior segment with a smartphone. Materials and Methods: A 90-diopter non-contact double aspheric lens was attached to posterior camera of the smartphone by clear tape. Images of one eye on the screen of the smartphone could be seen with the other eye in the mirror and images were taken. Results: Accurate and detailed images of the cornea and anterior segment of the eye could be taken. Conclusion: The ophthoselfie allows everyone to take their own detailed anterior segment images by smartphone. To create a clear and detailed self-image of the cornea and anterior segment on the screen of a smartphone may lead to the development of new applications and facilitate patients’ early recognition of certain conditions like keratoconus, refractive errors, corneal rejection, and uveitis. This method may also be useful in some urgent situations by allowing patients to take self-images of the eye and share them with a physician.

  6. Ophthoselfie: Detailed Self-imaging of Cornea and Anterior Segment by Smartphone.

    Science.gov (United States)

    Kaya, Abdullah

    2017-06-01

    To describe the ophthoselfie, a method by which everyone can take detailed self-images of the cornea and anterior segment with a smartphone. A 90-diopter non-contact double aspheric lens was attached to posterior camera of the smartphone by clear tape. Images of one eye on the screen of the smartphone could be seen with the other eye in the mirror and images were taken. Accurate and detailed images of the cornea and anterior segment of the eye could be taken. The ophthoselfie allows everyone to take their own detailed anterior segment images by smartphone. To create a clear and detailed self-image of the cornea and anterior segment on the screen of a smartphone may lead to the development of new applications and facilitate patients' early recognition of certain conditions like keratoconus, refractive errors, corneal rejection, and uveitis. This method may also be useful in some urgent situations by allowing patients to take self-images of the eye and share them with a physician.

  7. Contribution of the cornea and internal surfaces to the change of ocular aberrations with age

    Science.gov (United States)

    Artal, Pablo; Berrio, Esther; Guirao, Antonio; Piers, Patricia

    2002-01-01

    We studied the age dependence of the relative contributions of the aberrations of the cornea and the internal ocular surfaces to the total aberrations of the eye. We measured the wave-front aberration of the eye with a Hartmann-Shack sensor and the aberrations of the anterior corneal surface from the elevation data provided by a corneal topography system. The aberrations of the internal surfaces were obtained by direct subtraction of the ocular and corneal wave-front data. Measurements were obtained for normal healthy subjects with ages ranging from 20 to 70 years. The magnitude of the RMS wave-front aberration (excluding defocus and astigmatism) of the eye increases more than threefold within the age range considered. However, the aberrations of the anterior corneal surface increase only slightly with age. In most of the younger subjects, total ocular aberrations are lower than corneal aberrations, while in the older subjects the reverse condition occurs. Astigmatism, coma, and spherical aberration of the cornea are larger than in the complete eye in younger subjects, whereas the contrary is true for the older subjects. The internal ocular surfaces compensate, at least in part, for the aberrations associated with the cornea in most younger subjects, but this compensation is not present in the older subjects. These results suggest that the degradation of the ocular optics with age can be explained largely by the loss of the balance between the aberrations of the corneal and the internal surfaces.

  8. Safety levels for exposure of cornea and lens to very high-frequency ultrasound.

    Science.gov (United States)

    Silverman, R H; Lizzi, F L; Ursea, B G; Cozzarelli, L; Ketterling, J A; Deng, C X; Folberg, R; Coleman, D J

    2001-09-01

    Very high-frequency (50-MHz) ultrasound is widely used for imaging the anterior segment of the eye. Our aim was to determine whether exposures to ultrasound at and above those used in diagnostic imaging systems might cause bioeffects in ocular tissues. We characterized the output parameters of a polyvinylidene difluoride transducer using a needle hydrophone. We exposed sites on the cornea or lens of rabbits for up to 30 minutes at a 10-kHz pulse repetition frequency. Tissue obtained immediately or 24 hours after exposure was examined by light microscopy. A numeric model was implemented to calculate expected temperature elevations in the cornea and lens under experimental conditions. No tissue changes were observed directly or by slit lamp. Light microscopy showed no abnormalities attributable to ultrasound exposure. Simulations showed that even long-term exposures should produce temperature elevations of less than 1 degree C in both the cornea and lens. With the use of exposure parameters 4 to 5 orders of magnitude greater than encountered in a clinical situation, no tissue changes were observed. This is consistent with the small (0.2 degrees C) temperature rises computed in simulations. The lack of biological effects is attributable to the small dimensions of the focal zone, allowing rapid dissipation of heat, and the low total acoustic power produced by the transducer.

  9. Early expression of surfactant proteins D in Fusarium solani infected rat cornea.

    Science.gov (United States)

    Che, Cheng-Ye; Li, Xiao-Jing; Jia, Wen-Yan; Li, Na; Xu, Qiang; Lin, Jing; Wang, Qing; Jiang, Nan; Hu, Li-Ting; Zhao, Gui-Qiu

    2012-01-01

    To investigate the early expression of surfactant proteins D(SP-D) in Fusarium solani infected rat cornea. Wistar rats were divided into group A, B and C randomly. The right eyes were chosen as the experiment one. Group A was control group. Group B was not inoculated with Fusarium solani. Group C was taken as fusarium solani keratitis model. Five rats in group B and C were executed randomly at 6, 12, 24, 48 and 96 hours respectively after the experimental model being established. The expression of SP-D was assessed through immunohistochemistry and reverse transcription polymerase chain reaction(RT-PCR). RT-PCR detected that the SP-D mRNA expression was low in the corneal of normal rats and group B. The expression of fungal infected cornea increased gradually and reached the peak at 24 hours in group C. The synchronous expression of group B and C were in significant difference (Pfusarium solani infected cornea. SP-D may play a role in the early innate immunity response of the corneal resistance to Fusarium solani infection.

  10. In vivo multiphoton imaging of the cornea: polarization-resolved second harmonic generation from stromal collagen

    Science.gov (United States)

    Latour, G.; Gusachenko, I.; Kowalczuk, L.; Lamarre, I.; Schanne-Klein, M.-C.

    2012-03-01

    Multiphoton microscopy provides specific and contrasted images of unstained collagenous tissues such as tendons or corneas. Polarization-resolved second harmonic generation (SHG) measurements have been implemented in a laserscanning multiphoton microscope. Distortion of the polarimetric response due to birefringence and diattenuation during propagation of the laser excitation has been shown in rat-tail tendons. A model has been developed to account for these effects and correct polarization-resolved SHG images in thick tissues. This new modality is then used in unstained human corneas to access two quantitative parameters: the fibrils orientation within the collagen lamellae and the ratio of the main second-order nonlinear tensorial components. Orientation maps obtained from polarization resolution of the trans-detected SHG images are in good agreement with the striated features observed in the raw images. Most importantly, polarization analysis of the epi-detected SHG images also enables to map the fibrils orientation within the collagen lamellae while epi-detected SHG images of corneal stroma are spatially homogenous and do not enable direct visualization of the fibrils orientation. Depth profiles of the polarimetric SHG response are also measured and compared to models accounting for orientation changes of the collagen lamellae within the focal volume. Finally, in vivo polarization-resolved SHG is performed in rat corneas and structural organization of corneal stroma is determined using epi-detected signals.

  11. Property-based design: optimization and characterization of polyvinyl alcohol (PVA) hydrogel and PVA-matrix composite for artificial cornea.

    Science.gov (United States)

    Jiang, Hong; Zuo, Yi; Zhang, Li; Li, Jidong; Zhang, Aiming; Li, Yubao; Yang, Xiaochao

    2014-03-01

    Each approach for artificial cornea design is toward the same goal: to develop a material that best mimics the important properties of natural cornea. Accordingly, the selection and optimization of corneal substitute should be based on their physicochemical properties. In this study, three types of polyvinyl alcohol (PVA) hydrogels with different polymerization degree (PVA1799, PVA2499 and PVA2699) were prepared by freeze-thawing techniques. After characterization in terms of transparency, water content, water contact angle, mechanical property, root-mean-square roughness and protein adsorption behavior, the optimized PVA2499 hydrogel with similar properties of natural cornea was selected as a matrix material for artificial cornea. Based on this, a biomimetic artificial cornea was fabricated with core-and-skirt structure: a transparent PVA hydrogel core, surrounding by a ringed PVA-matrix composite skirt that composed of graphite, Fe-doped nano hydroxyapatite (n-Fe-HA) and PVA hydrogel. Different ratio of graphite/n-Fe-HA can tune the skirt color from dark brown to light brown, which well simulates the iris color of Oriental eyes. Moreover, morphologic and mechanical examination showed that an integrated core-and-skirt artificial cornea was formed from an interpenetrating polymer network, no phase separation appeared on the interface between the core and the skirt.

  12. Optics of the average normal cornea from general and canonical representations of its surface topography.

    Science.gov (United States)

    Navarro, Rafael; González, Luis; Hernández, José L

    2006-02-01

    Generally, the analysis of corneal topography involves fitting the raw data to a parametric geometric model that includes a regular basis surface, plus some sort of polynomial expansion to adjust the more irregular residual component. So far, these parametric models have been used in their canonical form, ignoring that the observation (keratometric) coordinate system is different from corneal axes of symmetry. Here we propose, instead, to use the canonical form when the topography is referenced to the intrinsic corneal system of coordinates, defined by its principal axes of symmetry. This idea is implemented using the general expression of an ellipsoid to fit the raw data given by the instrument. Then, the position and orientation of the three orthogonal semiaxes of the ellipsoid, which define the intrinsic Cartesian system of coordinates for normal corneas, can be identified by passing to the canonical form, by standard linear algebra. This model has been first validated experimentally obtaining significantly lower values for rms fitting error as compared with previous standard models: spherical, conical, and biconical. The fitting residual was then adjusted by a Zernike polynomial expansion. The topographies of 123 corneas were analyzed obtaining their radii of curvature, conic constants, Zernike coefficients, and the direction and position of the optical axis of the ellipsoid. The results were compared with those obtained using the standard models. The general ellipsoid model provides more negative values for the conic constants and lower apex radii (more prolate shapes) than the standard models applied to the same data. If the data are analyzed using standard models, the resulting mean shape of the cornea is consistent with previous studies, but when using the ellipsoid model we find new interesting features: The mean cornea is a more prolate ellipsoid (apical power 50 D), the direction of the optical axis is about 2.3 degrees nasal, and the residual term shows

  13. Optics of the average normal cornea from general and canonical representations of its surface topography

    Science.gov (United States)

    Navarro, Rafael; González, Luis; Hernández, José L.

    2006-02-01

    Generally, the analysis of corneal topography involves fitting the raw data to a parametric geometric model that includes a regular basis surface, plus some sort of polynomial expansion to adjust the more irregular residual component. So far, these parametric models have been used in their canonical form, ignoring that the observation (keratometric) coordinate system is different from corneal axes of symmetry. Here we propose, instead, to use the canonical form when the topography is referenced to the intrinsic corneal system of coordinates, defined by its principal axes of symmetry. This idea is implemented using the general expression of an ellipsoid to fit the raw data given by the instrument. Then, the position and orientation of the three orthogonal semiaxes of the ellipsoid, which define the intrinsic Cartesian system of coordinates for normal corneas, can be identified by passing to the canonical form, by standard linear algebra. This model has been first validated experimentally obtaining significantly lower values for rms fitting error as compared with previous standard models: spherical, conical, and biconical. The fitting residual was then adjusted by a Zernike polynomial expansion. The topographies of 123 corneas were analyzed obtaining their radii of curvature, conic constants, Zernike coefficients, and the direction and position of the optical axis of the ellipsoid. The results were compared with those obtained using the standard models. The general ellipsoid model provides more negative values for the conic constants and lower apex radii (more prolate shapes) than the standard models applied to the same data. If the data are analyzed using standard models, the resulting mean shape of the cornea is consistent with previous studies, but when using the ellipsoid model we find new interesting features: The mean cornea is a more prolate ellipsoid (apical power 50 D), the direction of the optical axis is about 2.3° nasal, and the residual term shows three

  14. Correlation of Biomicroscopic Findings with Confocal Microscopy in Eyes with Amiodarone-Induced Cornea Verticillata

    Directory of Open Access Journals (Sweden)

    Emine Kaya

    2014-01-01

    Full Text Available Objectives: To investigate the correlation between biomicroscopic and confocal microscopic findings in eyes with amiodarone-induced cornea verticillata. Materials and Methods: Sixteen eyes of 8 patients with amiodarone-induced cornea verticillata were evaluated. Eyes with keratopathy were staged according to Orlando slit-lamp microscopy classification. Confocal laser-scanning microscopy was performed by Rostock cornea modulated to HRT II (Heidelberg Engineering GmbH, Heidelberg, Germany, and staging was done according to Falke’s classification that is based on the degree of epithelial basal cell deposit accumulation. The relation between biomicroscopic staging and corneal involvement detected on confocal microscopy was assessed by Spearman correlation analysis. Results: The mean age of the 8 patients (5 male, 3 female was 63.1±7.2 (50 to 69 years. The mean duration of drug treatment was 12.1±11.8 (3 to 36 months, and the mean drug treatment dose was 312.5±223.2 (100 to 800 mg/day. At the time of examination, 50% of the patients had already given up the treatment at a mean of 29.5±15.8 (6 to 40 months ago, whereas the other 50% were still on amiodarone therapy. Hyper-reflecting deposits were observed in the basal epithelium, anterior-, mid-and deep-stroma, and in the endothelium on confocal microscopic examination. Correlation was detected between biomicroscopic and confocal microscopic stages (r=0.770, p<0.001. Frequency of detecting deposits in the stroma and endothelium was found to be increasing as the biomicroscopic stage increased (r=0.844; p<0.001 and r=0.551; p<0.01, respectively. Conclusion: In amiodarone-induced cornea verticillata, correlated results were detected between biomicroscopic and confocal microscopic staging. Therefore, in clinics where confocal microscopy is not available, biomicroscopic staging can be used as a guiding parameter in eyes with amiodarone-induced cornea verticillata. (Turk J Ophthalmol 2014; 44: 63-67

  15. Chronic Lunar Dust Exposure on Rat Cornea: Evaluation by Gene Expression Profiling

    Science.gov (United States)

    Theriot, C. A.; Glass, A.; Lam, C-W.; James, J.; Zanello, S. B.

    2014-01-01

    Lunar dust is capable of entering habitats and vehicle compartments by sticking to spacesuits or other objects that are transferred into the spacecraft from the lunar surface and has been reported to cause irritation upon exposure. During the Apollo missions, crewmembers reported irritation specifically to the skin and eyes after contamination of the lunar and service modules. It has since been hypothesized that ocular irritation and abrasion might occur as a result of such exposure, impairing crew vision. Recent work has shown that both ultrafine and unground lunar dust exhibited minimal irritancy of the ocular surface (i.e., cornea); however, the assessment of the severity of ocular damage resulting from contact of lunar dust particles to the cornea has focused only on macroscopic signs of mechanical irritancy and cytotoxicity. Given the chemical reactive properties of lunar dust, exposure of the cornea may contribute to detrimental effects at the molecular level including but not limited to oxidative damage. Additionally, low level chronic exposures may confound any results obtained in previous acute studies. We report here preliminary results from a tissue sharing effort using 10-week-old Fischer 344 male rats chronically exposed to filtered air or jet milled lunar dust collected during Apollo 14 using a Jaeger-NYU nose-only chamber for a total of 120 hours (6 hours daily, 5 days a week) over a 4-week period. RNA was isolated from corneas collected from rats at 1 day and 7 days after being exposed to concentrations of 0, 20, and 60 mg/m3 of lunar dust. Microarray analysis was performed using the Affymetrix GeneChip Rat Genome 230 2.0 Array with Affymetrix Expression Console and Transcriptome Analysis Console used for normalization and secondary analysis. An Ingenuity iReport"TM" was then generated for canonical pathway identification. The number of differentially expressed genes identified increases with dose compared to controls suggesting a more severe

  16. Validation of an endothelial roll preparation for Descemet Membrane Endothelial Keratoplasty by a cornea bank using "no touch" dissection technique.

    Science.gov (United States)

    Marty, Anne-Sophie; Burillon, Carole; Desanlis, Adeline; Damour, Odile; Kocaba, Viridiana; Auxenfans, Céline

    2016-06-01

    Descemet Membrane Endothelial Keratoplasty (DMEK) selectively replaces the damaged posterior part of the cornea. However, the DMEK technique relies on a manually-performed dissection that is time-consuming, requires training and presents a potential risk of endothelial graft damages leading to surgery postponement when performed by surgeons in the operative room. To validate precut corneal tissue preparation for DMEK provided by a cornea bank in order to supply a quality and security precut endothelial tissue. The protocol was a technology transfer from the Netherlands Institute for Innovative Ocular Surgery (NIIOS) to Lyon Cornea Bank, after formation in NIIOS to the DMEK "no touch" dissection technique. The technique has been validated in selected conditions (materials, microscope) and after a learning curve, cornea bank technicians prepared endothelial tissue for DMEK. Endothelial cells densities (ECD) were evaluated before and after preparation, after storage and transport to the surgery room. Microbiological and histological controls have been done. Twenty corneas were manually dissected; 18 without tears. Nineteen endothelial grafts formed a double roll. The ECD loss after cutting was 3.3 % (n = 19). After transportation 7 days later, we found an ECD loss of 25 % (n = 12). Three days after cutting and transportation, we found 2.1 % of ECD loss (n = 7). Histology found an endothelial cells monolayer lying on Descemet membrane. The mean thickness was 12 ± 2.2 µm (n = 4). No microbial contamination was found (n = 19). Endothelial roll stability has been validated at 3 days in our cornea bank. Cornea bank technicians trained can deliver to surgeons an ECD controlled, safety and ready to use endothelial tissue, for DMEK by "no touch" technique, allowing time saving, quality and security for surgeons.

  17. In vitro permeation characteristics of moxifloxacin from oil drops through excised goat, sheep, buffalo and rabbit corneas.

    Science.gov (United States)

    Pawar, P K; Majumdar, D K

    2007-11-01

    The objective of present investigation was to study the in vitro permeation characteristics of moxifloxacin from oil drops through freshly excised goat, sheep, buffalo and rabbit corneas. Moxifloxacin, 0.043 to 0.048% (w/v) ophthalmic solutions with or without (0.5% v/v) benzyl alcohol were made in arachis, castor, cottonseed, olive, soybean, sunflower and sesame oils. Permeation studies were conducted by putting 1 ml oil formulation on cornea (0.50 cm2) fixed between donor and receptor compartments of an all glass modified Franz diffusion cell and measuring the drug permeated in receptor (containing 10 ml bicarbonate ringer, pH 7.4 at 37 degrees C under stirring) by spectrophotometry at 291 nm, after 120 min. Post permeation corneal hydration was measured to assess corneal damage. The study was designed with paired corneas i.e. one cornea of an animal received formulation without benzyl alcohol while the contralateral cornea received formulation with benzyl alcohol. Moxifloxacin ophthalmic solution in castor oil showed maximum permeation with all the corneas. Addition of benzyl alcohol, a preservative, to oil drops reduced permeation of moxifloxacin from each oil drop, with corneas of all the species. Partition experiments with moxifloxacin oil drops and phosphate buffer (pH 7.4) indicated higher partitioning of drug in the oil phase, in presence of benzyl alcohol. Thus results of permeation are consistent with the partition characteristics of drug between oil and aqueous phase. Corneal hydration obtained with all the formulations was between 75 to 80% indicating no corneal damage.

  18. Corneal Collagen Cross-Linking with Hypoosmolar Riboflavin Solution in Keratoconic Corneas

    Directory of Open Access Journals (Sweden)

    Shaofeng Gu

    2014-01-01

    Full Text Available Purpose. To report the 12-month outcomes of corneal collagen cross-linking (CXL with a hypoosmolar riboflavin and ultraviolet-A (UVA irradiation in thin corneas. Methods. Eight eyes underwent CXL using a hypoosmolar riboflavin solution after epithelial removal. The corrected distance visual acuity (CDVA, manifest refraction, the mean thinnest corneal thickness (MTCT, and the endothelial cell density (ECD were evaluated before and 6 and 12 months after CXL. Results. The MTCT was 413.9 ± 12.4 μm before treatment and reduced to 381.1 ± 7.3 μm after the removal of the epithelium. After CXL, the thickness decreased to 410.3 ± 14.5 μm at the last follow-up. Before treatment, the mean K-value of the apex of the keratoconus corneas was 58.7 ± 3.5 diopters and slightly decreased (57.7 ± 4.9 diopters at 12 months. The mean CDVA was 0.54 ± 0.23 logarithm of the minimal angle of resolution before treatment and increased to 0.51 ± 0.21 logarithm at the last follow-up. The ECD was 2731.4 ± 191.8 cells/mm2 before treatment and was 2733.4 ± 222.6 cells/mm2 at 12 months after treatment. Conclusions. CXL with a hypoosmolar riboflavin in thin corneas seems to be a promising method for keratoconic eyes with the mean thinnest corneal thickness less than 400 μm without epithelium.

  19. Localization and expression of CHST6 and keratan sulfate proteoglycans in the human cornea.

    Science.gov (United States)

    Di Iorio, Enzo; Barbaro, Vanessa; Volpi, Nicola; Bertolin, Marina; Ferrari, Barbara; Fasolo, Adriano; Arnaldi, Renato; Brusini, Paolo; Prosdocimo, Giovanni; Ponzin, Diego; Ferrari, Stefano

    2010-08-01

    Macular corneal dystrophy (MCD; OMIM 217800) is a rare autosomal recessive inherited disorder caused by mutations in the carbohydrate sulfotransferase 6 (CHST6) and characterised by the presence of unsulfated keratan sulfate proteoglycans (KSPGs) forming abnormal deposits that eventually lead to visual impairment. The aim of this study is to understand in which corneal cells CHST6 and KSPGs are expressed and exert their activity. Expression and localization of CHST6, keratan sulfate (KS) and proteins of the KSPGs, such as mimecan and lumican, were assessed both in human cornea sections and in cultured primary keratinocytes (n = 3) and keratocytes (n = 4). Immunohistochemistry, semiquantitative RT-PCR, in situ RNA hybridization and HPLC analysis of glycosaminoglycans were used as read-outs. In human corneas KS was predominantly found in the stroma, but absent, or barely detectable, in the corneal epithelium. A similar pattern of distribution was found in the epidermis, with KS mainly localised in the derma. As expected, in the cornea CHST6 (the gene encoding the enzyme which transfers sulfate residues onto KSPGs) was found expressed in the suprabasal, but not basal, layers of the epithelium, in the stroma and in the endothelium. Analyses of KS by means of HPLC showed that in vitro cultured stromal keratocytes express and secrete more KS than keratinocytes, thus mirroring results observed in vivo. Similarly expression of the CHST6 gene and of KS proteoglycans such as mimecan, lumican is limited to stromal keratocytes. Unlike keratocytes, corneal keratinocytes do not synthesize mimecan or lumican, and express very little, if none, CHST6. Any drug/gene therapy or surgical intervention aimed at curing this rare genetic disorder must therefore involve and target stromal keratocytes. If coupled to the accuracy of HPLC-based assay that we developed to determine the amount of KS in serum, our findings could lead to more targeted therapeutic treatments of the ocular features

  20. Biocompatibility of poly(ethylene glycol) and poly(acrylic acid) interpenetrating network hydrogel by intrastromal implantation in rabbit cornea.

    Science.gov (United States)

    Zheng, Luo Luo; Vanchinathan, Vijay; Dalal, Roopa; Noolandi, Jaan; Waters, Dale J; Hartmann, Laura; Cochran, Jennifer R; Frank, Curtis W; Yu, Charles Q; Ta, Christopher N

    2015-10-01

    We evaluated the biocompatibility of a poly(ethylene glycol) and poly(acrylic acid) (PEG/PAA) interpenetrating network hydrogel designed for artificial cornea in a rabbit model. PEG/PAA hydrogel measuring 6 mm in diameter was implanted in the corneal stroma of twelve rabbits. Stromal flaps were created with a microkeratome. Randomly, six rabbits were assigned to bear the implant for 2 months, two rabbits for 6 months, two rabbits for 9 months, one rabbit for 12 months, and one rabbit for 16 months. Rabbits were evaluated monthly. After the assigned period, eyes were enucleated, and corneas were processed for histology and immunohistochemistry. There were clear corneas in three of six rabbits that had implantation of hydrogel for 2 months. In the six rabbits with implant for 6 months or longer, the corneas remained clear in four. There was a high rate of epithelial defect and corneal thinning in these six rabbits. One planned 9-month rabbit developed extrusion of implant at 4 months. The cornea remained clear in the 16-month rabbit but histology revealed epithelial in-growth. Intrastromal implantation of PEG/PAA resulted in a high rate of long-term complications.

  1. Ethical Considerations on Heterogeneous Cornea Transplant%异种角膜移植的伦理考量

    Institute of Scientific and Technical Information of China (English)

    张燕

    2011-01-01

    由于移植技术的进步以及异种角膜移植技术自身的优势,异种角膜移植有望成为眼科临床常规诊疗手段之一,为缓解同种角膜移植供体短缺的压力提供可能.分析了异种角膜移植的可行性,并就异种角膜移植涉及的部分伦理问题、安全性问题;人的同一性及完整性问题;患者接受度问题;角膜供体资源管理和分配问题;动物保护问题进行了探讨.%According to advanced transplantation technology and the advantages of comeal stroma, heterogeneous cornea transplant is expected to become one of the conventional means of ophthalmology clinical treatment,and it provides the possibility for easing the shortage of the same cornea transplant donation. This paper analyzed the feasibility of heterogeneous cornea transplant and discussed some ethical issues about heterogeneous cornea transplant: safety issue, people in the identity and integrity problems, degree about patients received, heterogeneous donor cornea resources management and distribution issue and animal protection issue.

  2. Case report: a novel KERA mutation associated with cornea plana and its predicted effect on protein function

    DEFF Research Database (Denmark)

    Roos, Laura; Bertelsen, Birgitte; Harris, Pernille;

    2015-01-01

    Background: Cornea plana (CNA) is a hereditary congenital abnormality of the cornea characterized by reduced corneal curvature, extreme hypermetropia, corneal clouding and hazy corneal limbus. The recessive form, CNA2, is associated with homozygous or compound heterozygous mutations of the kerato......Background: Cornea plana (CNA) is a hereditary congenital abnormality of the cornea characterized by reduced corneal curvature, extreme hypermetropia, corneal clouding and hazy corneal limbus. The recessive form, CNA2, is associated with homozygous or compound heterozygous mutations...... of the keratocan gene (KERA) on chromosome 12q22. To date, only nine different disease-associated KERA mutations, including four missense mutations, have been described. Case presentation: In this report, we present clinical data from a Turkish family with autosomal recessive cornea plana. In some of the affected...... individuals, hypotrichosis was found. KERA was screened for mutations using Sanger sequencing. We detected a novel KERA variant, p.(Ile225Thr), that segregates with the disease in the homozygous form. The three-dimensional structure of keratocan protein was modelled, and we showed that this missense variation...

  3. In vivo 3D measurement of moxifloxacin and gatifloxacin distributions in the mouse cornea using multiphoton microscopy

    Science.gov (United States)

    Lee, Seunghun; Lee, Jun Ho; Park, Jin Hyoung; Yoon, Yeoreum; Chung, Wan Kyun; Tchah, Hungwon; Kim, Myoung Joon; Kim, Ki Hean

    2016-05-01

    Moxifloxacin and gatifloxacin are fourth-generation fluoroquinolone antibiotics used in the clinic to prevent or treat ocular infections. Their pharmacokinetics in the cornea is usually measured from extracted ocular fluids or tissues, and in vivo direct measurement is difficult. In this study multiphoton microscopy (MPM), which is a 3D optical microscopic technique based on multiphoton fluorescence, was applied to the measurement of moxifloxacin and gatifloxacin distribution in the cornea. Intrinsic multiphoton fluorescence properties of moxifloxacin and gatifloxacin were characterized, and their distributions in mouse cornea in vivo were measured by 3D MPM imaging. Both moxifloxacin and gatifloxacin had similar multiphoton spectra, while moxifloxacin had stronger fluorescence than gatifloxacin. MPM imaging of mouse cornea in vivo showed (1) moxifloxacin had good penetration through the superficial corneal epithelium, while gatifloxacin had relatively poor penetration, (2) both ophthalmic solutions had high intracellular distribution. In vivo MPM results were consistent with previous studies. This study demonstrates the feasibility of MPM as a method for in vivo direct measurement of moxifloxacin and gatifloxacin in the cornea.

  4. [Difficult cornea procurement: causes and consequences of the exceptional situation in France].

    Science.gov (United States)

    Delbosc, B

    2000-02-01

    Despite scientific advances, corneal grafting is still in a crucial situation in France in 1999. Over the last 3 years, the number of corneal grafts (2 903 in 1996, 3 213 in 1997, and 4 053 in 1998) has been insufficient to satisfy estimated needs (8 041 in 1996, 8 303 in 1997, 7 400 in 1998). The consequences are waiting lists, long time on waiting lists, and regional differences. This situation results more from difficulties in the cornea procurement system than from limited numbers of potential donors or restricted selection criteria. Progress will depend greatly on structural changes.

  5. Comparison of Scheimpflug imaging parameters between steep and keratoconic corneas of Caucasian eyes

    Directory of Open Access Journals (Sweden)

    Huseynova T

    2016-04-01

    Full Text Available Tukezban Huseynova,1 Farah Abdulaliyeva,2 Michele Lanza3 1Briz-L Eye Clinic, 2National Ophthalmology Center, Baku, Azerbaijan; 3Second University of Naples, Caserta, Campania, Italy Purpose: To compare the keratometric and pachymetric parameters of healthy eyes with those affected by steep cornea and keratoconus (KC using Scheimpflug camera.Setting: Briz-L Eye Clinic, Baku, Azerbaijan.Design: A cross-sectional study.Methods: In this study, 49 KC (Amsler–Krumeich stage 1 eyes and 36 healthy eyes were enrolled. A complete ophthalmic evaluation and a Scheimpflug camera scan were performed in every eye included in the study. Tomographic parameters such as parameters from the front and back cornea, maximum keratometry reading (Kmax, corneal volume (CV, anterior chamber volume (ChV, anterior chamber depth (ACD, anterior chamber angle (AC angle, keratometric power deviation (KPD, maximum front elevation (Max FE, and maximum back elevation (Max BE, as well as pachymetric progression indices (PPI, Ambrosio relational thickness (ART, index of surface variance (ISV, index of vertical asymmetry (IVA, center keratoconus index (CKI, index of height asymmetry (IHA, index of height decentration (IHD, and radius minimum (RM were collected and statistically compared between the two groups.Results: PPI, ART, ISV, IVA, CKI, IHA, IHD, and RM parameter values were significantly different (P<0.05 between the KC and healthy eyes. There were no significant differences in K mean and Q values of the frontal corneal parameters, as well as in Kmax, AC angle, RM, back, and front astigmatism, between stage 1 keratoconic and normal Caucasian eyes with steep cornea. All other parameters such as K mean and Q values of the back corneal parameters, Max FE, Max BE, ACD, ChV, and CV showed significant differences between the groups (P<0.05 for all. Conclusion: Scheimpflug imaging is able to detect corneal morphological differences between stage 1 KC eyes and healthy eyes with

  6. Optics of the human cornea influence the accuracy of stereo eye-tracking methods: a simulation study.

    Science.gov (United States)

    Barsingerhorn, A D; Boonstra, F N; Goossens, H H L M

    2017-02-01

    Current stereo eye-tracking methods model the cornea as a sphere with one refractive surface. However, the human cornea is slightly aspheric and has two refractive surfaces. Here we used ray-tracing and the Navarro eye-model to study how these optical properties affect the accuracy of different stereo eye-tracking methods. We found that pupil size, gaze direction and head position all influence the reconstruction of gaze. Resulting errors range between ± 1.0 degrees at best. This shows that stereo eye-tracking may be an option if reliable calibration is not possible, but the applied eye-model should account for the actual optics of the cornea.

  7. Deleterious Mutations in the Zinc-Finger 469 Gene Cause Brittle Cornea Syndrome

    Science.gov (United States)

    Abu, Almogit; Frydman, Moshe; Marek, Dina; Pras, Eran; Nir, Uri; Reznik-Wolf, Haike; Pras, Elon

    2008-01-01

    Brittle cornea syndrome (BCS) is an autosomal-recessive disorder characterized by a thin cornea that tends to perforate, causing progressive visual loss and blindness. Additional systemic symptoms such as joint hypermotility, hyperlaxity of the skin, and kyphoscoliosis place BCS among the connective-tissue disorders. Previously, we assigned the disease gene to a 4.7 Mb interval on chromosome 16q24. In order to clone the BCS gene, we first narrowed the disease locus to a 2.8 Mb interval and systematically sequenced genes expressed in connective tissue in this chromosomal segment. We have identified two frameshift mutations in the Zinc-Finger 469 gene (ZNF469). In five unrelated patients of Tunisian Jewish ancestry, we found a 1 bp deletion at position 5943 (5943 delA), and in an inbred Palestinian family we detected a single-nucleotide deletion at position 9527 (9527 delG). The function of ZNF469 is unknown. However, a 30% homology to a number of collagens suggests that it could act as a transcription factor involved in the synthesis and/or organization of collagen fibers. PMID:18452888

  8. Two-photon autofluorescence lifetime and SHG imaging of healthy and diseased human corneas

    Science.gov (United States)

    Batista, Ana; Breunig, Hans Georg; Uchugonova, Aisada; Seitz, Berthold; Morgado, António Miguel; König, Karsten

    2015-03-01

    Corneal function can be drastically affected by several degenerations and dystrophies, leading to blindness. Early diagnosis of corneal disease is of major importance and it may be accomplished by monitoring changes of the metabolic state and structural organization, the first detectable pathological signs, by two-photon excitation autofluorescence lifetime and second-harmonic generation imaging. In this study, we propose to use these imaging techniques to differentiate between healthy and pathological corneas. Images were acquired using a laser-scanning microscope with a broadband sub-15 femtosecond near-infrared pulsed laser and a 16-channel photomultiplier tube detector for signal collection. This setup allows the simultaneous excitation of metabolic co-factors and to identify them based on their fluorescence spectra. We were able to discriminate between healthy and pathological corneas using two-photon excitation autofluorescence lifetime and second-harmonic generation imaging from corneal epithelium and stroma. Furthermore, differences between different pathologies were observed. Alterations in the metabolic state of corneal epithelial cells were observed using the autofluorescence lifetime of the metabolic co-factors. In the corneal stroma, we observed not only alterations in the collagen fibril structural organization but also alterations in the autofluorescence lifetime. Further tests are required as the number of pathological samples must be increased. In the future, we intend to establish a correlation between the metabolic and structural changes and the disease stage. This can be a step forward in achieving early diagnosis.

  9. Control of Scar Tissue Formation in the Cornea: Strategies in Clinical and Corneal Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Samantha L. Wilson

    2012-09-01

    Full Text Available Corneal structure is highly organized and unified in architecture with structural and functional integration which mediates transparency and vision. Disease and injury are the second most common cause of blindness affecting over 10 million people worldwide. Ninety percent of blindness is permanent due to scarring and vascularization. Scarring caused via fibrotic cellular responses, heals the tissue, but fails to restore transparency. Controlling keratocyte activation and differentiation are key for the inhibition and prevention of fibrosis. Ophthalmic surgery techniques are continually developing to preserve and restore vision but corneal regression and scarring are often detrimental side effects and long term continuous follow up studies are lacking or discouraging. Appropriate corneal models may lead to a reduced need for corneal transplantation as presently there are insufficient numbers or suitable tissue to meet demand. Synthetic optical materials are under development for keratoprothesis although clinical use is limited due to implantation complications and high rejection rates. Tissue engineered corneas offer an alternative which more closely mimic the morphological, physiological and biomechanical properties of native corneas. However, replication of the native collagen fiber organization and retaining the phenotype of stromal cells which prevent scar-like tissue formation remains a challenge. Careful manipulation of culture environments are under investigation to determine a suitable environment that simulates native ECM organization and stimulates keratocyte migration and generation.

  10. Control of scar tissue formation in the cornea: strategies in clinical and corneal tissue engineering.

    Science.gov (United States)

    Wilson, Samantha L; El Haj, Alicia J; Yang, Ying

    2012-09-18

    Corneal structure is highly organized and unified in architecture with structural and functional integration which mediates transparency and vision. Disease and injury are the second most common cause of blindness affecting over 10 million people worldwide. Ninety percent of blindness is permanent due to scarring and vascularization. Scarring caused via fibrotic cellular responses, heals the tissue, but fails to restore transparency. Controlling keratocyte activation and differentiation are key for the inhibition and prevention of fibrosis. Ophthalmic surgery techniques are continually developing to preserve and restore vision but corneal regression and scarring are often detrimental side effects and long term continuous follow up studies are lacking or discouraging. Appropriate corneal models may lead to a reduced need for corneal transplantation as presently there are insufficient numbers or suitable tissue to meet demand. Synthetic optical materials are under development for keratoprothesis although clinical use is limited due to implantation complications and high rejection rates. Tissue engineered corneas offer an alternative which more closely mimic the morphological, physiological and biomechanical properties of native corneas. However, replication of the native collagen fiber organization and retaining the phenotype of stromal cells which prevent scar-like tissue formation remains a challenge. Careful manipulation of culture environments are under investigation to determine a suitable environment that simulates native ECM organization and stimulates keratocyte migration and generation.

  11. Evaluating the material parameters of the human cornea in a numerical model.

    Science.gov (United States)

    Sródka, Wiesław

    2011-01-01

    The values of the biomechanical human eyeball model parameters reported in the literature are still being disputed. The primary motivation behind this work was to predict the material parameters of the cornea through numerical simulations and to assess the applicability of the ubiquitously accepted law of applanation tonometry - the Imbert-Fick equation. Numerical simulations of a few states of eyeball loading were run to determine the stroma material parameters. In the computations, the elasticity moduli of the material were related to the stress sign, instead of the orientation in space. Stroma elasticity secant modulus E was predicted to be close to 0.3 MPa. The numerically simulated applanation tonometer readings for the cornea with the calibration dimensions were found to be lower by 11 mmHg then IOP = 48 mmHg. This discrepancy is the result of a strictly mechanical phenomenon taking place in the tensioned and simultaneously flattened corneal shell and is not related to the tonometer measuring accuracy. The observed deviation has not been amenable to any GAT corrections, contradicting the Imbert-Fick law. This means a new approach to the calculation of corrections for GAT readings is needed.

  12. Cornea Collagen Cross-linking for Keratoconus: A Comparison between Accelerated and Conventional Methods

    Science.gov (United States)

    Razmjoo, Hasan; Peyman, Alireza; Rahimi, Ali; Modrek, Hoda Jafari

    2017-01-01

    Background: Keratoconus is a progressive degenerative disorder of the cornea in which structural changes in the cornea cause it to become thin and conical in shape. Recently, collagen cross-linking (CXL) has been introduced as an effective intervention in management of progressive keratoconus. Accelerated CXL is a new protocol of this procedure which reduces corneal ultraviolet irradiation exposure time to 5 min. This study aimed to compare visual acuity, keratometry and topographic criteria of keratoconic eyes after conventional and accelerated CXL with a six-month follow-up. Materials and Methods: In this prospective interventional study we assessed eyes of 40 patients. Patients were divided into two groups randomly. One group underwent accelerated (5 min) CXL and the other underwent conventional (30 min) CXL. Visual acuity, topographic criteria and keratometry were assessed preoperatively and 6 months postoperatively. Results: In the present study we assessed 40 patients, 50% of which were right eye (OD) and 50% were left eye (OS). Mean age of patients in the accelerated group was 22.10 and in the conventional group was 22.80 years. Our results showed no significant differences between visual acuity, keratometric and topographic criteria in the two groups before intervention. Likewise our results manifested no significant difference between visual acuity, keratometric, refractive and topographic criteria after intervention. Conclusion: According to our survey topographic criteria and keratometry improvement in the accelerated and conventional protocol are the same. So accelerated protocol is suggested as a safe and effective option for management of progressive keratoconus. PMID:28299302

  13. Animal study on expression of laminin and fibronectin in cornea during wound healing following alkali burn

    Institute of Scientific and Technical Information of China (English)

    赵桂秋; 马轶群; 梁涛; 姜涛; 王传富; 张妍霞

    2003-01-01

    Objective: To observe the expression of laminin and fibronectin in alkali-burned corneas in rats.Methods: A total of 18 normal Wistar rats were randomly divided into 6 groups (n=3 in each group). For each rat, one eye was injured by alkali burn, the other one was taken as the normal control. Then all the corneas were surgically removed and the expression of laminin and fibronectin was observed with immunohistochemistry respectively at 7 hours, 1 day, 3 days, 7 days, 14 days and 28 days after alkali burn. Results: Compared with that of the normal controls, the expression of laminin and fibronectin of the burned eyes was dramatically higher at 7 hours, reached peak at 14 days and decreased to the normal level at 28 days after alkali burn. Conclusions: In the process of wound healing after alkali burn, the expression of laminin and fibronectin increases dramatically, which suggests that laminin and fibronectin may participate in the process of corneal wound healing.

  14. Pre- and postoperative optical resolution of the cornea: a preliminary report

    Science.gov (United States)

    Parel, Jean-Marie A.; Simon, Gabriel; Rol, Pascal O.; Ren, Qiushi; Lee, William E.

    1993-06-01

    The effect of novel refractive surgical techniques on visual acuity and contrast sensitivity is normally determined by the outcome of human clinical trials. For example, ArF laser photorefractive keratoplasty follows an algorithm based on the patient's preoperative data for keratometry, refraction, pachometry, and ocular length all measured with ultrasound. A normalized ablation rate (which is function of the laser fluence), and the desired refractive correction are then used to calculate the ablation depth. On the day of surgery, the epithelium is mechanically removed and the bare cornea photoablated. Finally, the cornea may be medicated with a topical application of antibiotics and the eye is patched. On postoperative day 7, the epithelium is healed and visual acuity and keratometry are measured. With PRK, the theoretical outcome refraction should be within +/- 0.25 D. Thus far however, reproducibility is only of +/- 2 D. We believe the large discrepancy between theory and practice is due to several parameters that vary patient-to-patient.

  15. Chromosome mutations and tissue regeneration in the cornea after the UV laser irradiation

    Science.gov (United States)

    Razhev, Alexander M.; Bagayev, Sergei N.; Lebedeva, Lidya I.; Akhmametyeva, Elena M.; Zhupikov, Andrey A.

    2003-06-01

    In present paper the findings on chromosome mutations, the nature of damage and the repair of the cornea tissue after UV irradiation by excimer lasers at 193, 223 and 248 nm were made. Structural mutations induced by short-pulses UV irradiation were shown to be similar to spontaneous ones by the type, time of formation in the mitotic cycle and location of acentrics. Ten hours after irradiation of the cornea with doses of 0,09 to 1,5 J/cm2 the incidence of cells with chromosome aberrations increased linearly with dose and amounted to 11,7% at 248 nm, 5,5% at 223 nm and 2,6% at 193 nm per 1 J/cm2. No induced chromosome aberrations occurred 72 hour following irradiation. Within the dose range from 3,0 to 18 J/cm2 the cytogenesis effect of radiation was less manifest than that with the doses mentioned above, the frequency of chromosome aberrations being independent of either radiation wavelength or radiation dose and amounted of 2,5 to 3,0%. Thus, large doses of powerful short-pulse UV radiation are safe according to the structural mutation criterion.

  16. Geometrical custom modeling of human cornea in vivo and its use for the diagnosis of corneal ectasia.

    Directory of Open Access Journals (Sweden)

    Francisco Cavas-Martínez

    Full Text Available AIM: To establish a new procedure for 3D geometric reconstruction of the human cornea to obtain a solid model that represents a personalized and in vivo morphology of both the anterior and posterior corneal surfaces. This model is later analyzed to obtain geometric variables enabling the characterization of the corneal geometry and establishing a new clinical diagnostic criterion in order to distinguish between healthy corneas and corneas with keratoconus. METHOD: The method for the geometric reconstruction of the cornea consists of the following steps: capture and preprocessing of the spatial point clouds provided by the Sirius topographer that represent both anterior and posterior corneal surfaces, reconstruction of the corneal geometric surfaces and generation of the solid model. Later, geometric variables are extracted from the model obtained and statistically analyzed to detect deformations of the cornea. RESULTS: The variables that achieved the best results in the diagnosis of keratoconus were anterior corneal surface area (ROC area: 0.847, p<0.000, std. error: 0.038, 95% CI: 0.777 to 0.925, posterior corneal surface area (ROC area: 0.807, p<0.000, std. error: 0.042, 95% CI: 0,726 to 0,889, anterior apex deviation (ROC area: 0.735, p<0.000, std. error: 0.053, 95% CI: 0.630 to 0.840 and posterior apex deviation (ROC area: 0.891, p<0.000, std. error: 0.039, 95% CI: 0.8146 to 0.9672. CONCLUSION: Geometric modeling enables accurate characterization of the human cornea. Also, from a clinical point of view, the procedure described has established a new approach for the study of eye-related diseases.

  17. Assessing the viscoelasticity of green light induced CXL in the rabbit cornea by noncontact OCE and FEM

    Science.gov (United States)

    Han, Zhaolong; Li, Jiasong; Singh, Manmohan; Vantipalli, Srilatha; Aglyamov, Salavat R.; Wu, Chen; Liu, Chih-hao; Twa, Michael D.; Larin, Kirill V.

    2016-03-01

    The biomechanical properties of the cornea have a profound influence on its health and function. Rose bengal/green light corneal collagen cross-linking (RGX) has been proposed as an alternative to UV-A Riboflavin collagen cross-linking (UV-CXL) for treatment of keratoconus. However, the effects of RGX on the biomechanical properties of the cornea are not as well understood as UV-CXL. In this work, we demonstrate the feasibility of quantifying the viscoelasticity of the rabbit cornea before and after RGX using a noncontact method of phase-stabilized swept source optical coherence elastography (PhS-SSOCE) and finite element modeling (FEM). Viscoelastic FE models of the corneas were constructed to simulate the elastic wave propagation based on the OCE measurements. In addition, the effect of the fluid-structure interface (FSI) between the corneal posterior surface and aqueous humor on the elastic wave group velocity was also investigated. The effect of the FSI was first validated by OCE measurements and FEM simulations on contact lenses, and the OCE and FEM results were in good agreement. The Young's modulus of the rabbit cornea before RGX was assessed as E=80 kPa, and the shear viscosity was η=0.40 Pa•s at an intraocular pressure (IOP) of 15 mmHg. After RGX, the Young's modulus increased to E=112 kPa and shear viscosity decreased to η=0.37 Pa•s. Both the corneal OCE experiments and the FE simulations also demonstrated that the FSI significantly reduced the group velocity of the elastic wave, and thus, the FSI should be considered when determining the biomechanical properties of the cornea.

  18. Morphologic and histopathologic changes in the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation.

    Science.gov (United States)

    Zhang, Zhen-Yong; Chu, Ren-Yuan; Zhou, Xing-Tao; Dai, Jin-Hui; Sun, Xing-Huai; Hoffman, Matthew R; Zhang, Xing-Ru

    2009-05-01

    To observe morphologic and histopathologic changes in the midperiphery of the rabbit cornea produced by femtosecond laser-assisted multilayer intrastromal ablation, determine whether this method may be used to correct myopia, and study how the cornea heals when the epithelium is not injured. The right eyes of 10 New Zealand White rabbits were used for the experiments. A 60-kHz femtosecond laser delivery system was used, and three lamellar layers of laser pulses were focused starting at a corneal depth of 180 microm and ending at 90 microm from the surface, with each successive layer placed 45 microm anterior to the previous layer. In the interface of the applanation contact lens cone, a 6-mm diameter aluminum circle was placed at the center to block the laser, and ablation was limited to the midperiphery of the cornea. The laser settings were spot/line separation, 10 microm; diameter, 8.5 mm; energy for ablating the stroma, 1.3 microJ. Topography examination was used to document changes in corneal power. Light microscopy, transmission electron microscopy (TEM), and confocal microscopy in vivo were applied to observe changes in the cornea. There was significant change in mean corneal power between baseline and postoperative month 3 (n = 8; P = 0.0001), with a decrease from 46.82 D to 44.42 D. There was no haze formation or refractive regression throughout the follow-up. There were no corneal structural abnormalities under light microscopy. Activated keratocytes and necrotic debris were visible under confocal microscopy. Fibroblasts were observed, and no myofibroblasts appeared under TEM. Multilayer intrastromal ablation by the femtosecond laser with intact epithelium in the midperiphery of the corneal stroma can flatten the cornea without causing haze formation or refractive regression. This procedure allows the cornea to heal differently than when traditional corneal refractive surgery is performed and the epithelium is damaged.

  19. EFFECT OF DONOR CORNEA PRESERVATION IN TISSUE-CULTURE AND IN MCCAREY-KAUFMANN MEDIUM ON CORNEAL GRAFT-REJECTION AND VISUAL-ACUITY

    NARCIS (Netherlands)

    MOLL, AC; VANRIJ, G; BEEKHUIS, WH; DELAVALETTE, JHCR; HERMANS, J; PELS, E; RINKELVANDRIEL, E

    1991-01-01

    In a retrospective study the rate of rejection and clouding of the donor cornea for other reasons was investigated in 230 penetrating keratoplasties performed between 1984-1986. Donor corneas were stored in McCarey-Kaufmann Medium (MK) at 4-degrees-C or in a modified Minimal Essential Medium (MEM)

  20. Isolation and characterization of soluble sulfated polysaccharide from the red seaweed Glucaric cornea; Isolamento e caracterizacao do polissacarideo sulfatado soluvel extraido da alga vermelha Gracilaria cornea

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Marcia R.S.; Freitas, Ana L.P. [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Bioquimica e Biologia Molecular]. E-mail: rubiamelo@yahoo.com; Feitosa, Judith P.A.; Paula, Regina C.M. de [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica]. E-mail: judith@dqoi.ufc.br

    2001-07-01

    The composition, structure and rheological properties of soluble sulphated polysaccharide Glucaric cornea from Brazilian red seaweeds were investigated. The main components of polysaccharide were 3,6-anhydrogalactose (24.7%) and galactose (64.6%). In addition, minor components as 6-O-methyl-galactose (8.5%), glucose (1.5%), xylose (0.7%) and sulfated groups (4.8%) were detected. Comparison between sulphates content determined by Ft-IR spectroscopy and micro elemental analysis was made. Data from {sup 13}C NMR and FT-IR provided evidence of sulphation in C-4 and C-6 of galactose. No gelation with 1.5, 2.0 and 3.0 % (w/v) aqueous solution was observed, even cooled up to 4 deg C. GPC indicated two majors polysaccharide fractions of M{sub pk} 7.4 x 10{sup 4} and 1.8 x 10{sup 4} g/mol and a minor fraction of M{sub pk} 2.1 x 10{sup 6} g/mol. (author)

  1. Global and local contributions to surface curva- ture of healthy corneas

    Directory of Open Access Journals (Sweden)

    Alan Rubin

    2012-12-01

    Full Text Available This paper demonstrates for several healthy eyes the application of a simple model to understanding local and global contributions to short-term variation in anterior and posterior corneal curvature. Multiple axial anterior and posterior corneal radii and central corneal thicknesses for the right eyes of 10 young subjects were determined over time using a rotating Scheimpflug camera (Oculus Pentacam. The axial radii were transformed to corneal powers, and also to curvatures that were referred to a mid-corneal surface such that local and global contributions to short-term variation could be analyzed quantitatively.When variation of the anterior and posterior corneal surfaces of several healthy eyes are studied in terms of curvatures (rather than powers it is the posterior surfaces that are more variable withthe global or macroscopic rather than local effects dominating. (Harris and Gillan found the same for an eye with mild keratoconus. This finding is opposite to that when variation is considered in terms of dioptric power where the anterior corneal surface usually appears more variable. Possible reasons for this finding includes firstly that the posterior corneal surface has to be measured through the air-tear interface and anterior corneal surface,and thus some uncertainty in measurements of the posterior surface may relate to this limitation. Secondly, no attempt was made here to mathematically align the multiple surfaces as determined per eye and thus we cannot be certain that precisely the same central corneal region was measured each time.Investigators need to carefully consider whether they are more interested in the optical or physical nature of variation in surfaces such as the cornea since studies of the optical effects require theanalysis to be performed in terms of dioptric powers and  symmetric dioptric power space whereas studies of physical variation in the topography of the cornea and the possible reasons for such variability

  2. Changes in biomechanical properties of the cornea after modified transepithelial crosslinking

    Directory of Open Access Journals (Sweden)

    I. B. Medvedev

    2016-01-01

    Full Text Available The aim of the study was to evaluate changes in biomechanical properties of the cornea after conducting transepithelial crosslinking with the prior application of a 40 % glucose solution.Materials and methods. Just studied the biomechanical properties of the corneas of six rabbits breed Chinchilla (12 eyes. 4 rabbit entered in the experimental group, in which in one eye glucose solution was applied on the cornea and allowed to stay for 10 minutes, followed by the instillation of 0.1 % Riboflavin solution for 30 minutes. On a couple of the rabbit eye was applied a solution of Riboflavin without prior instillation of glucose. Then carried out the procedure of irradiation according to the conventional technology with UV with a wavelength of 370 μm and a beam energy of 3.0 mW / cm2. Two rabbits (4 eyes were included in the control group, in which crosslinking was not performed. After 1 month the euthanasia of the animals was performed with subsequent enucleation for corneal research on a tensile testing machine. In the control and experimental group compared, the relaxation curves and the following parameters were analyzed: initial stress (MPa, equilibrium stress (MPa modulus of elasticity.Results and their discussion. After the crosslinking the rise of the initial stress (in the control group and 0.7+0.1 MPa, in the experimental and 1.5+0.2 1.3+0.3 MPa, respectively. The stress relaxation is fast (equilibrium stress value is reached after 250 sec. and after the administration of glucose for approximately 75 seconds, which means a greater rigidity of experimental group of samples. In the experimental groups significantly changed and the modulus of elasticity: its value has increased approximately in 2 times in comparison with control samples. The equilibrium stress values in the experimental groups were different from the zero value that also indicates a change in the chemical structure of the samples.Conclusions. Holding transepithelial of

  3. Clinical performance of KeraSoft® IC in irregular corneas

    Directory of Open Access Journals (Sweden)

    Su S

    2015-10-01

    Full Text Available Stephanie Su,1 Lynette Johns,2 Marjorie J Rah,3 Robert Ryan,1 Joseph Barr3 1Visionary Eye Associates of Rochester, Rochester, NY, USA; 2Custom Lab Channel Business, Bausch & Lomb Incorporated, Wilmington, MA, USA; 3Medical Affairs – Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: This study evaluated the clinical performance of KeraSoft® IC (KIC soft contact lenses in subjects with irregular corneas.Patients and methods: This was a 12-month, prospective, open-label, observational study, which enrolled 43 subjects who were 18 years of age or older with irregular corneas. Subjects were fit according to the KIC Fitting Manual (kerasoftic.com. After achieving best fit according to the fitting manual, lenses were assessed for comfort, vision, centration, rotation, and movement. Subjects were instructed to wear their lenses between 8 and 16 hours each day. Assessments at the exit visit included logMAR visual acuity with high and low contrast, spherocylindrical overrefraction, slit-lamp findings, adverse events, and subjective outcomes.Results: The average base curve was 8.17±0.32 mm (n=70 eyes, and the average diameter dispensed was 14.53±0.12 mm (n=70 eyes. From the baseline to 12 months, there was statistically significant improvement in logMAR visual acuity with high contrast (P=0.038, but no significant difference in low-contrast visual acuity was observed (P>0.05. Slit-lamp findings were ≤ grade 1 for the majority of subjects (89%. Two nonserious adverse events were reported for two of the 84 enrolled eyes (two subjects. At 12 months, subjects reported improvements from habitual baseline for comfort and vision, both upon insertion and just before removal of lenses.Conclusion: Clinical outcomes at 12 months showed good visual, safety, and subjective outcomes for subjects with corneal irregularities who wore KeraSoft® IC soft contact lenses. Keywords: irregular corneas, keratoconus, soft contact lenses, KeraSoft® IC

  4. Fibre optic spectrophotometry for the in vitro evaluation of ultraviolet radiation (UVR) spectral transmittance of rabbit corneas.

    Science.gov (United States)

    Walsh, J E; Bergmanson, J P G; Koehler, L V; Doughty, M J; Fleming, D P; Harmey, J H

    2008-03-01

    A fibre optic spectrophotometer front-end system for measuring corneas to overcome shortcomings associated with existing instruments was tested. The system allowed prompt measurement postmortem, minimizing beam pathlength to reduce the effects of scatter and unwanted refraction and eliminated optical interfaces and cuvette media. Rabbit corneas were excised immediately postmortem and placed on a detecting fibre optic coupled to an Ocean Optics spectrophotometer and illuminated by a deuterium-halogen source. The compact instrument with its small beam size allowed tissue profiling at test points across the corneal surface and efficient interchange for comparison of different tissues. This simplified system operation allowed rapid tissue altering to study induced changes on transmittance. The corneal transmittance data showed a consistent sharp cut-off at 320 nm in the ultraviolet radiation (UVR) spectrum, which decayed rapidly from postmortem swelling. Inter- and intra-corneal consistency was demonstrated by comparing data from different regions of the same cornea and those from opposite eyes. Changes to the spectra, particularly in the UVB below 300 nm, were evident when the corneal epithelium was removed, indicating that this layer is not the only corneal UVR filter. The new system reduced much of the variability associated with previous methods, as it rapidly measured corneal transmittance postmortem. Data are in broad agreement with published transmittance curves. The removal of the corneal epithelium revealed a substantial stromal contribution to the overall corneal UVR absorption, suggesting that corneas with pathologically or iatrogenically thinned stromas are less effective UVR blockers.

  5. Mutations in PRDM5 in Brittle Cornea Syndrome Identify a Pathway Regulating Extracellular Matrix Development and Maintenance

    NARCIS (Netherlands)

    Wright, Emma M. M. Burkitt; Spencer, Helen L.; Daly, Sarah B.; Manson, Forbes D. C.; Zeef, Leo A. H.; Urquhart, Jill; Zoppi, Nicoletta; Bonshek, Richard; Tosounidis, Ioannis; Mohan, Meyyammai; Madden, Colm; Dodds, Annabel; Chandler, Kate E.; Banka, Siddharth; Au, Leon; Clayton-Smith, Jill; Khan, Naz; Biesecker, Leslie G.; Wilson, Meredith; Rohrbach, Marianne; Colombi, Marina; Giunta, Cecilia; Black, Graeme C. M.

    2011-01-01

    Extreme corneal fragility and thinning, which have a high risk of catastrophic spontaneous rupture, are the cardinal features of brittle cornea syndrome (BCS), an autosomal-recessive generalized connective tissue disorder. Enucleation is frequently the only management option for this condition,

  6. Induction of morphological and electrophysiological changes in hamster cornea after in vitro interaction with trophozoites of Acanthamoeba spp.

    Science.gov (United States)

    Omaña-Molina, Maritza; Navarro-García, Fernando; González-Robles, Arturo; Serrano-Luna, José de Jesús; Campos-Rodríguez, Rafael; Martínez-Palomo, Adolfo; Tsutsumi, Víctor; Shibayama, Mineko

    2004-06-01

    Acanthamoeba castellani and Acanthamoeba polyphaga are free-living amebae that cause keratitis and granulomatous encephalitis in humans. We have analyzed the early morphological and electrophysiological changes occurring during the in vitro interaction of cultured amebae with intact or physically damaged corneas obtained from hamsters. Both species of Acanthamoeba produced similar cytopathic changes, as seen by light microscopy and scanning electron microscopy. After adhesion to the epithelial surface, trophozoites formed clumps and migrated toward the cell borders, causing the separation of adjacent cells at 1 h of coculture. At later stages (2 to 4 h), some amebae were found under desquamating epithelial cells whereas others were seen associated with damaged cells or forming amebostome-like structures to ingest detached epithelial cells. Control corneas incubated in culture medium conditioned with amebae showed a cytoplasmic vacuolization and blurring of the epithelial-stromal junction. The early stages of corneal epithelial damage caused by amebae were also analyzed by measuring the transepithelial resistance changes in corneas mounted in Ussing chambers. Both species of Acanthamoeba caused a rapid decrease in electrical resistance. The present observations demonstrate that under in vitro conditions, Acanthamoeba trophozoites rapidly cause significant damage to the corneal epithelium. Furthermore, in our experimental model, previous physical damage to the corneas was not a prerequisite for the development of amebic corneal ulcerations.

  7. Force analysis of bacterial transmission from contact lens cases to corneas, with the contact lens as the intermediary

    NARCIS (Netherlands)

    Qu, Wen-wen; Hooymans, Johanna MM; de Vries, Jacob; van der Mei, Henderina; Busscher, Hendrik

    2011-01-01

    PURPOSE. To determine the probability of transmission of a Staphylococcus aureus strain from a contact lens case, to the contact lens (CL) surfaces, to the cornea, on the basis of bacterial adhesion forces measured by using atomic force microscopy (AFM). METHODS. Adhesion forces between S. aureus st

  8. Optical properties of the human cornea : Shape and wave aberration measurements using the VU topographer and Scheimpflug photography

    NARCIS (Netherlands)

    Sicam, V.A.D.P.

    2007-01-01

    In this study, the optical properties of the human cornea was investigated. Two major developments were made because current measurement techniques need improvement First, the VU topographer, which uses a color coded pattern, was validated with real eye data showing better performance compare to co

  9. Collection, processing and testing of bone, corneas, umbilical cord blood and haematopoietic stem cells by European Blood Alliance members

    DEFF Research Database (Denmark)

    Närhi, M; Natri, O; Desbois, I;

    2013-01-01

    A questionnaire study was carried out in collaboration with the European Blood Alliance (EBA) Tissues and Cells (T&C) working group. The aim was to assess the level of involvement and commonality of processes on the procurement, testing and storage of bone, corneas, umbilical cord blood (UCB...

  10. Cultured corneas show dendritic spread and restrict herpes simplex virus infection that is not observed with cultured corneal cells

    Science.gov (United States)

    Thakkar, Neel; Jaishankar, Dinesh; Agelidis, Alex; Yadavalli, Tejabhiram; Mangano, Kyle; Patel, Shrey; Tekin, Sati Zeynep; Shukla, Deepak

    2017-01-01

    Herpes simplex virus-1 (HSV-1) causes life-long morbidities in humans. While fever blisters are more common, occasionally the cornea is infected resulting in vision loss. A very intriguing aspect of HSV-1 corneal infection is that the virus spread is normally restricted to only a small fraction of cells on the corneal surface that connect with each other in a dendritic fashion. Here, to develop a comprehensive understanding of the susceptibility of human corneal epithelial (HCE) cells to HSV-1 infection, we infected HCE cells at three different dosages of HSV-1 and measured the outcomes in terms of viral entry, gene and protein expression, viral replication and cytokine induction. In cultured cells, infectivity and cytokine induction were observed even at the minimum viral dosage tested, while a more pronounced dose-restricted infectivity was seen in ex vivo cultures of porcine corneas. Use of fluorescent HSV-1 virions demonstrated a pattern of viral spread ex vivo that mimics clinical findings. We conclude that HCE cell cultures are highly susceptible to infection whereas the cultured corneas demonstrate a higher ability to restrict the infection even in the absence of systemic immune system. The restriction is helped in part by local interferon response and the unique cellular architecture of the cornea. PMID:28198435

  11. Corneal Sulfated Glycosaminoglycans and Their Effects on Trigeminal Nerve Growth Cone Behavior In Vitro: Roles for ECM in Cornea Innervation

    OpenAIRE

    Schwend, Tyler; Deaton, Ryan J.; Zhang, Yuntao; Caterson, Bruce; Conrad, Gary W.

    2012-01-01

    In this investigation, we describe differential spatiotemporal expression patterns of glycosaminoglycans KS, DS, and CSA/C during developmental stages of cornea innervation. We show that purified GAGs have divergent effects on trigeminal neuron behavior using in vitro neuronal explant cultures.

  12. Mutations in PRDM5 in Brittle Cornea Syndrome Identify a Pathway Regulating Extracellular Matrix Development and Maintenance

    NARCIS (Netherlands)

    Wright, Emma M. M. Burkitt; Spencer, Helen L.; Daly, Sarah B.; Manson, Forbes D. C.; Zeef, Leo A. H.; Urquhart, Jill; Zoppi, Nicoletta; Bonshek, Richard; Tosounidis, Ioannis; Mohan, Meyyammai; Madden, Colm; Dodds, Annabel; Chandler, Kate E.; Banka, Siddharth; Au, Leon; Clayton-Smith, Jill; Khan, Naz; Biesecker, Leslie G.; Wilson, Meredith; Rohrbach, Marianne; Colombi, Marina; Giunta, Cecilia; Black, Graeme C. M.

    2011-01-01

    Extreme corneal fragility and thinning, which have a high risk of catastrophic spontaneous rupture, are the cardinal features of brittle cornea syndrome (BCS), an autosomal-recessive generalized connective tissue disorder. Enucleation is frequently the only management option for this condition, resu

  13. Automatic pterygium detection on cornea images to enhance computer-aided cortical cataract grading system.

    Science.gov (United States)

    Gao, Xinting; Wong, Damon Wing Kee; Aryaputera, Aloysius Wishnu; Sun, Ying; Cheng, Ching-Yu; Cheung, Carol; Wong, Tien Yin

    2012-01-01

    In this paper, we present a new method to detect pterygiums using cornea images. Due to the similarity of appearances and spatial locations between pterygiums and cortical cataracts, pterygiums are often falsely detected as cortical cataracts on retroillumination images by a computer-aided grading system. The proposed method can be used to filter out the pterygium which improves the accuracy of cortical cataract grading system. This work has three major contributions. First, we propose a new pupil segmentation method for visible wavelength images. Second, an automatic detection method of pterygiums is proposed. Third, we develop an enhanced compute-aided cortical cataract grading system that excludes pterygiums. The proposed method is tested using clinical data and the experimental results demonstrate that the proposed method can improve the existing automatic cortical cataract grading system.

  14. Brittle Cornea Syndrome Associated with a Missense Mutation in the Zinc-Finger 469 Gene

    DEFF Research Database (Denmark)

    Christensen, Anne Elisabeth; Knappskog, Per Morten; Midtbø, Marit

    2010-01-01

    Purpose: To investigate the diverse clinical manifestations, identify the causative mutation and explain the association with red hair in a family with brittle cornea syndrome (BCS). Methods: Eight family members in three generations underwent ophthalmic, dental, and general medical examination......, dental anomalies, hearing loss and minor cardiac defects. The morphologies of the skin biopsies were normal except that in some areas slightly thinner collagen fibrils were seen in one of the affected individuals. Molecular genetic analysis revealed a novel missense mutation of ZNF469, c.10016G....... Reduced BMD and atypical dental crown morphology have not been reported previously. We confirm that BCS is associated with mutations in ZNF469. The association with red hair in some individuals with BCS is likely to occur by chance....

  15. Cadmium toxicity to the cornea of pregnant rats: Electron microscopy and x-ray microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizuka, M.; McCarthy, K.J.; Kaye, G.I.; Fujimoto, S. (Univ. of Occupational and Environmental Health, School of Medicine, Kitakyushu (Japan))

    1990-05-01

    Cadmium toxicity to the cornea of pregnant rats was studied using the electron microscope and x-ray microanalyzer. In in-vivo experiments, severe corneal edema occurred in pregnant dams that received intraperitoneal injections of cadmium sulphate for 4 days during gestation, but not in nonpregnant rats. Prominent swelling of mitochondria and the occurrence of intra- and intercellular vacuoles in the corneal endothelium were observed only in pregnant dams. In in-vitro experiments, electron-dense deposits consisting of cadmium-oxine complexes were preferentially found in swollen mitochondria of the endothelial cells. Cadmium peaks were obtained from these deposits with x-ray microanalysis. These data suggest that the corneal edema observed after administration of cadmium may imply the disturbance of pump function and barrier function of the corneal endothelium due to the primary toxic effects of this metal on mitochondria.

  16. A simplified technique for in situ excision of cornea and evisceration of retinal tissue from human ocular globe.

    Science.gov (United States)

    Parekh, Mohit; Ferrari, Stefano; Di Iorio, Enzo; Barbaro, Vanessa; Camposampiero, Davide; Karali, Marianthi; Ponzin, Diego; Salvalaio, Gianni

    2012-06-12

    Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the retrieval of ocular tissues, especially cornea, by cutting it separate from the ocular globe. Evisceration is the process of removing the internal organs referred here as retina. The ocular globe consists of the cornea, the sclera, the vitreous body, the lens, the iris, the retina, the choroid, muscles etc (Suppl. Figure 1). When a patient is suffering from corneal damage, the cornea needs to be removed and a healthy one must be transplanted by keratoplastic surgeries. Genetic disorders or defects in retinal function can compromise vision. Human ocular globes can be used for various surgical procedures such as eye banking, transplantation of human cornea or sclera and research on ocular tissues. However, there is little information available on human corneal and retinal excision, probably due to the limited accessibility to human tissues. Most of the studies describing similar procedures are performed on animal models. Research scientists rely on the availability of properly dissected and well-conserved ocular tissues in order to extend the knowledge on human eye development, homeostasis and function. As we receive high amount of ocular globes out of which approximately 40% (Table 1) of them are used for research purposes, we are able to perform huge amount of experiments on these tissues, defining techniques to excise and preserve them regularly. The cornea is an avascular tissue which enables the transmission of light onto the retina and for this purpose should always maintain a good degree of transparency. Within the cornea, the limbus region, which is a reservoir of the stem cells, helps the reconstruction of epithelial cells and restricts the overgrowth of the conjunctiva maintaining corneal transparency and clarity. The size and thickness of the cornea are critical for clear vision, as changes in either of them

  17. In vivo laser confocal microscopy findings of a cornea with osteogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Kobayashi A

    2014-02-01

    Full Text Available Akira Kobayashi, Tomomi Higashide, Hideaki Yokogawa, Natsuko Yamazaki, Toshinori Masaki, Kazuhisa Sugiyama Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan Objective: To report the in vivo laser confocal microscopy findings of a cornea with osteogenesis imperfecta (OI with special attention to the abnormality of Bowman's layer and sub-Bowman's fibrous structures (K-structures. Patients and methods: Two patients (67-year-old male and his 26-year-old son with OI type I were included in this study. Slit lamp biomicroscopic and in vivo laser confocal microscopic examinations were performed for both patients. Central corneal thickness and central endothelial cell density were also measured. Results: Although the corneas looked clear with normal endothelial density for both eyes in both patients, they were quite thin (386 µm oculus dexter (OD (the right eye and 384 µm oculus sinister (OS (the left eye in the father and 430 µm OD and 425 µm OS in the son. In both patients, slit lamp biomicroscopic and in vivo laser confocal microscopic examination showed similar results. Anterior corneal mosaics produced by rubbing the eyelid under fluorescein were completely absent in both eyes. In vivo laser confocal microscopy revealed an absent or atrophic Bowman's layer; a trace of a presumed Bowman's layer and/or basement membrane was barely visible with high intensity. Additionally, K-structures were completely absent in both eyes. Conclusion: The absence of K-structures and fluorescein anterior corneal mosaics strongly suggested an abnormality of Bowman's layer in these OI patients. Keywords: osteogenesis imperfecta, K-structure, confocal microscopy, Bowman's layer

  18. Pathogenic strains of Acanthamoeba are recognized by TLR4 and initiated inflammatory responses in the cornea.

    Science.gov (United States)

    Alizadeh, Hassan; Tripathi, Trivendra; Abdi, Mahshid; Smith, Ashley Dawn

    2014-01-01

    Free-living amoebae of the Acanthamoeba species are the causative agent of Acanthamoeba keratitis (AK), a sight-threatening corneal infection that causes severe pain and a characteristic ring-shaped corneal infiltrate. Innate immune responses play an important role in resistance against AK. The aim of this study is to determine if Toll-like receptors (TLRs) on corneal epithelial cells are activated by Acanthamoeba, leading to initiation of inflammatory responses in the cornea. Human corneal epithelial (HCE) cells constitutively expressed TLR1, TLR2, TLR3, TLR4, and TLR9 mRNA, and A. castellanii upregulated TLR4 transcription. Expression of TLR1, TLR2, TLR3, and TLR9 was unchanged when HCE cells were exposed to A. castellanii. IL-8 mRNA expression was upregulated in HCE cells exposed to A. castellanii. A. castellanii and lipopolysaccharide (LPS) induced significant IL-8 production by HCE cells as measured by ELISA. The percentage of total cells positive for TLR4 was higher in A. castellanii stimulated HCE cells compared to unstimulated HCE cells. A. castellanii induced upregulation of IL-8 in TLR4 expressing human embryonic kidney (HEK)-293 cells, but not TLR3 expressing HEK-293 cells. TLR4 neutralizing antibody inhibited A. castellanii-induced IL-8 by HCE and HEK-293 cells. Clinical strains but not soil strains of Acanthamoeba activated TLR4 expression in Chinese hamster corneas in vivo and in vitro. Clinical isolates but not soil isolates of Acanthamoeba induced significant (PAcanthamoeba activate TLR4 and induce production of CXCL2 in the Chinese hamster model of AK. TLR4 may be a potential target in the development of novel treatment strategies in Acanthamoeba and other microbial infections that activate TLR4 in corneal cells.

  19. Turnover of bone marrow-derived cells in the irradiated mouse cornea

    Science.gov (United States)

    Chinnery, Holly R; Humphries, Timothy; Clare, Adam; Dixon, Ariane E; Howes, Kristen; Moran, Caitlin B; Scott, Danielle; Zakrzewski, Marianna; Pearlman, Eric; McMenamin, Paul G

    2008-01-01

    In light of an increasing awareness of the presence of bone marrow (BM)-derived macrophages in the normal cornea and their uncertain role in corneal diseases, it is important that the turnover rate of these resident immune cells be established. The baseline density and distribution of macrophages in the corneal stroma was investigated in Cx3cr1gfp transgenic mice in which all monocyte-derived cells express enhanced green fluorescent protein (eGFP). To quantify turnover, BM-derived cells from transgenic eGFP mice were transplanted into whole-body irradiated wild-type recipients. Additionally, wild-type BM-derived cells were injected into irradiated Cx3cr1+/gfp recipients, creating reverse chimeras. At 2, 4 and 8 weeks post-reconstitution, the number of eGFP+ cells in each corneal whole mount was calculated using epifluorescence microscopy, immunofluorescence staining and confocal microscopy. The total density of myeloid-derived cells in the normal Cx3cr1+/gfp cornea was 366 cells/mm2. In BM chimeras 2 weeks post-reconstitution, 24% of the myeloid-derived cells had been replenished and were predominantly located in the anterior stroma. By 8 weeks post-reconstitution 75% of the myeloid-derived cells had been replaced and these cells were distributed uniformly throughout the stroma. All donor eGFP+ cells expressed low to moderate levels of CD45 and CD11b, with approximately 25% coexpressing major histocompatibility complex class II, a phenotype characteristic of previous descriptions of corneal stromal macrophages. In conclusion, 75% of the myeloid-derived cells in the mouse corneal stroma are replenished after 8 weeks. These data provide a strong basis for functional investigations of the role of resident stromal macrophages versus non-haematopoietic cells using BM chimeric mice in models of corneal inflammation. PMID:18540963

  20. Ultraviolet-visible light spectral transmittance of rabbit corneas after riboflavin/ultraviolet-A (365 nm) corneal collagen cross-linking.

    Science.gov (United States)

    Hwang, Ho Sik; Kim, Man Soo

    2013-01-01

    To determine the effect of riboflavin/ultraviolet-A (365 nm) corneal collagen cross-linking on the transmission of the ultraviolet-visible (UV-VIS) light spectrum through the cornea. Twelve New Zealand white male rabbits were used in this research. Cross-linking was performed unilaterally on the right eyes of the animals while only the epithelium was removed on the left eyes as the control. Seven weeks after cross-linking, the animals were euthanized, and the enucleated eyes were processed for transmission spectroscopy. To confirm that the cross-linking procedures was done successfully on the right corneas, the tensile force-extension relationship was measured using six corneas from three of the rabbits after the transmission spectrum was determined. Seven weeks after cross-linking, ten of the 12 rabbits had clear corneas in the cross-linked and control eyes. The two rabbits with neovascularization and granular opacities in the right corneas were not included in subsequent measurements. In the cross-linked corneas, transmittance was 87.57% at 650 nm, and decreased continuously as the wavelength shortened. From 315 nm, the transmittance rapidly decreased and was 35.52% at 300 nm. In the control corneas, transmittance was 95.95% at 650 nm and decreased continuously as the wavelength shortened. Below 315 nm, the transmittance rapidly decreased, to 40.29% at 300 nm. The transmittance of the cross-linking corneas was 10%-20% lower than that of the control corneas. The difference was 8.38% at 650 nm and increased as the wavelength shortened, reaching a maximum of 20.59% at 320 nm, and decreased rapidly to 4.77% at 300 nm. The tensile force-extension relationship showed that a greater force was necessary to extend the cross-linking corneas over 500 µm than that of the control corneas. The transmittance of the cross-linked corneas was 10%-20% lower than that of the control corneas. The difference increased as the wavelength decrease, reaching a maximum at 320 nm and then

  1. Clinical and epidemiological aspects of cornea transplant patients of a reference hospital.

    Science.gov (United States)

    Cruz, Giovanna Karinny Pereira; Azevedo, Isabelle Campos de; Carvalho, Diana Paula de Souza Rego Pinto; Vitor, Allyne Fortes; Santos, Viviane Euzébia Pereira; Ferreira, Marcos Antonio

    2017-06-08

    clinically characterizing cornea transplant patients and their distribution according to indicated and post-operative conditions of cornea transplantation, as well as estimating the average waiting time. a cross-sectional, descriptive and analytical study performed for all cornea transplants performed at a reference service (n=258). Data were analyzed using Statistical Package for the Social Sciences, version 20.0. the main indicator for cornea transplant was keratoconus. The mean waiting time for the transplant was approximately 5 months and 3 weeks for elective transplants and 9 days for urgent cases. An association between the type of corneal disorder with gender, age, previous surgery, eye classification, glaucoma and anterior graft failure were found. keratoconus was the main indicator for cornea transplant. Factors such as age, previous corneal graft failure (retransplantation), glaucoma, cases of surgeries prior to cornea transplant (especially cataract surgery) may be related to the onset corneal endothelium disorders. caracterizar clínicamente los pacientes trasplantados y su distribución, con descripción de las condiciones indicadoras y posoperatorias de los trasplantes de córneas, así como estimar el tiempo promedio en la fila de espera. estudio epidemiológico, transversal, descriptivo y analítico, realizado con todos los trasplantes de córnea realizados en un servicio de referencia (n=258). Los datos fueron analizados con el software Statistical Package for the Social Sciences, versión 20.0. la principal condición indicadora para el trasplante de córnea fue el queratocono. El tiempo promedio en fila de espera para realización del trasplante fue de aproximadamente 5 meses y tres semanas, para trasplantes electivos y de 9 días para los casos de urgencia. Existió asociación entre el tipo de disturbio de la córnea con: sexo, intervalo etario, cirugía previa, clasificación del ojo, glaucoma y rechazo del injerto anterior. el queratocono fue

  2. Amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis

    Institute of Scientific and Technical Information of China (English)

    Bo; Zeng; Ping; Wang; Ling-Juan; Xu; Xin-Yu; Li; Hong; Zhang; Gui-Gang; Li

    2014-01-01

    AIM:To investigate the effect of amniotic membrane covering(AMC) on the healing of cornea epithelium and visual acuity for fungal keratitis after debridement.METHODS:Twenty fungal keratitis patients were divided into two groups randomly, the AMC group and the control group, ten patients each group. Both debridement of the infected cornea tissue and standard anti-fungus drugs treatments were given to every patients, monolayer amniotic membrane were sutured to the surface of the entire cornea and bulbar conjunctiva with 10-0 nylon suture for patients in the AMC group.The diameter of the ulcer was determined with slit lamp microscope and the depth of the infiltration was determined with anterior segment optical coherence tomography. Uncorrected visual acuity(UCVA) was tested before surgery and three month after healing of the epithelial layer. The healing time of the cornea epithelium, visual acuity(VA) was compared between the two groups using t- test.RESULTS:There was no statistical difference of the diameter of the ulcer, depth of the infiltration, height of the hypopyon and VA between the two groups beforesurgery(P >0.05). The average healing time of the AMC group was 6.89 ±2.98 d, which was statistically shorter than that of the control group(10.23±2.78d)(P <0.05).The average UCVA of the AMC group was 0.138 ±0.083,which was statistically better than that of the control group(0.053±0.068)(P <0.05).CONCLUSION:AMC surgery could promote healing of cornea epithelium after debridement for fungal keratitis and lead to better VA outcome.

  3. Novel micelle carriers for cyclosporin A topical ocular delivery: in vivo cornea penetration, ocular distribution and efficacy studies.

    Science.gov (United States)

    Di Tommaso, Claudia; Bourges, Jean-Louis; Valamanesh, Fatemeh; Trubitsyn, Gregory; Torriglia, Alicia; Jeanny, Jean-Claude; Behar-Cohen, Francine; Gurny, Robert; Möller, Michael

    2012-06-01

    Cornea transplantation is one of the most performed graft procedures worldwide with an impressive success rate of 90%. However, for "high-risk" patients with particular ocular diseases in addition to the required surgery, the success rate is drastically reduced to 50%. In these cases, cyclosporin A (CsA) is frequently used to prevent the cornea rejection by a systemic treatment with possible systemic side effects for the patients. To overcome these problems, it is a challenge to prepare well-tolerated topical CsA formulations. Normally high amounts of oils or surfactants are needed for the solubilization of the very hydrophobic CsA. Furthermore, it is in general difficult to obtain ocular therapeutic drug levels with topical instillations due to the corneal barriers that efficiently protect the intraocular structures from foreign substances thus also from drugs. The aim of this study was to investigate in vivo the effects of a novel CsA topical aqueous formulation. This formulation was based on nanosized polymeric micelles as drug carriers. An established rat model for the prevention of cornea graft rejection after a keratoplasty procedure was used. After instillation of the novel formulation with fluorescent labeled micelles, confocal analysis of flat-mounted corneas clearly showed that the nanosized carriers were able to penetrate into all corneal layers. The efficacy of a 0.5% CsA micelle formulation was tested and compared to a physiological saline solution and to a systemic administration of CsA. In our studies, the topical CsA treatment was carried out for 14 days, and the three parameters (a) cornea transparency, (b) edema, and (c) neovascularization were evaluated by clinical observation and scoring. Compared to the control group, the treated group showed a significant higher cornea transparency and significant lower edema after 7 and 13 days of the surgery. At the end point of the study, the neovascularization was reduced by 50% in the CsA-micelle treated

  4. OrbscanⅡ角膜地形图系统筛查亚临床期圆锥角膜%Screening of Subclinical Keratoconus by OrbscanⅡ Cornea Topography

    Institute of Scientific and Technical Information of China (English)

    虞林丽; 赵刚平; 朱敏; 王艳华; 李追; 赵岭江; 张亚军

    2012-01-01

    Objective To evaluate the features of cornea topography in subclinical keratoconus. Methods Orbscan II cornea topography system was performed on 15 patients(26 eyes) with subclinical keratoconus. Diff values of cornea anterior surface and posterior surface, thickness of the thinnest cornea, center refractive power of cornea, and simulated keratometry were measured. Results Diff values of cornea anterior surface and posterior surface in subclinical keratoconus were 0. 025 and 0. 050 mm respectively, thickness of the thinnest cornea was (450.65 + 35.67) μm;SimK was (4. 55 + 1. 09)D, and center refractive power of cornea was (47. 1 ±3. 5) D. Diff value of cornea anterior surface had a positive correlation with diff value of cornea posterior surface and center refractive power of cornea. Conclusion Orbscan JJ cornea topography system can provide morphological basis for early diagnosis of subclinical keratoconus.%目的 研究亚临床期圆锥角膜的角膜地形图改变的特点.方法 应用 OrbscanⅡ角膜地形图系统检测15例(26只眼)亚临床期圆锥角膜患者的角膜,得到角膜前表面和后表面Diff 值、角膜最薄点厚度、角膜中央屈光力及角膜模拟镜差值(SimK 值),了解亚临床期圆锥角膜的敏感性指标以及各指标之间的相关关系.结果 亚临床期圆锥角膜的角膜前表面Diff 值是0.025 mm,角膜后表面Diff 值为0.050 mm;角膜最薄点厚度(450.65±35.67)μm;SimK值为(4.55±1.09)D;角膜中央屈光力为(47.1 ±3.5)D.角膜前表面Diff值与角膜后表面Diff值、角膜中央屈光力呈正相关关系;角膜后表面Diff值与角膜中央屈光力呈正相关关系.结论 OrbscanⅡ角膜地形图系统可为早期诊断亚临床期圆锥角膜提供形态学依据.

  5. Reconstruction of damaged cornea by autologous transplantation of epidermal adult stem cells.

    Science.gov (United States)

    Yang, Xueyi; Moldovan, Nicanor I; Zhao, Qingmei; Mi, Shengli; Zhou, Zhenhui; Chen, Dan; Gao, Zhimin; Tong, Dewen; Dou, Zhongying

    2008-06-05

    It is crucial for the treatment of severe ocular surface diseases such as Stevens-Johnson syndrome (SJS) and ocular cicatricial pemphigoid (OCP) to find strategies that avoid the risks of allograft rejection and immunosuppression. Here, we report a new strategy for reconstructing the damaged corneal surface in a goat model of total limbal stem cell deficiency (LSCD) by autologous transplantation of epidermal adult stem cells (EpiASC). EpiASC derived from adult goat ear skin by explant culture were purified by selecting single cell-derived clones. These EpiASC were cultivated on denuded human amniotic membrane (HAM) and transplanted onto goat eyes with total LSCD. The characteristics of both EpiASC and reconstructed corneal epithelium were identified by histology and immunohistochemistry. The clinical characteristic of reconstructed corneal surface was observed by digital camera. Ten LSCD goats (10 eyes) were treated with EpiASC transplantation, leading to the restoration of corneal transparency and improvement of postoperative visual acuity to varying degrees in 80.00% (8/10) of the experimental eyes. The corneal epithelium of control groups either with HAM transplantation only or without any transplantation showed irregular surfaces, diffuse vascularization, and pannus on the entire cornea. The reconstructed corneal epithelium (RCE) expressed CK3, CK12, and PAX-6 and had the function of secreting glycocalyx-like material (AB-PAS positive). During the follow-up period, all corneal surfaces remained transparent and there were no serious complications. We also observed that the REC expressed CK1/10 weakly at six months after operation but not at 12 months after operation, suggesting that the REC was derived from grafted EpiASC. Our results showed that EpiASC repaired the damaged cornea of goats with total LSCD and demonstrated that EpiASC can be induced to differentiate into corneal epithelial cell types in vivo, which at least in part correlated with down

  6. Immunogenicity of a Moraxella bovis bacterin containing attachment and cornea-degrading enzyme antigens.

    Science.gov (United States)

    Gerber, J D; Selzer, N L; Sharpee, R L; Beckenhauer, W H

    1988-02-01

    An adjuvanted Moraxella bovis bacterin containing attachment antigens and cornea-degrading enzyme antigens protected cattle from infectious bovine keratoconjunctivitis (IBK) when experimentally challenged with homologous and heterologous challenge cultures of M. bovis. This bacterin also protected cattle against field exposure to M. bovis. Transmission electron microscopy and fluorescein labeled anti-M. bovis pili antiserum showed pili on the M. bovis bacterin strain. Scanning electron microscopy demonstrated a fibrillar glycocalyx. The bacterin strain of M. bovis, but not all strains of M. bovis, destroyed bovine corneal cell monolayers in vitro. Bovine corneal cells began to separate from each other within 5 min after M. bovis organisms were added and adhered to the cell monolayers. Moraxella bovis organisms remained attached to the disintegrating cells as the cell membrane separated and was digested. Vaccination stimulated bacterial agglutination antibodies. However, protection against experimental challenge was more closely related to the cornea-degrading enzyme content of the experimental bacterins. Twenty-two of 29 cattle (76%) vaccinated with bacterins containing a relative enzyme activity (REA) greater than 0.4 were protected in a rigorous challenge of immunity test. Only 1 of 21 non-vaccinated calves (5%) was free of IBK. Ninety-two percent (24/26) of calves vaccinated with a bacterin containing a REA greater than 0.29 remained free of IBK following field exposure, whereas 47% (8/17) non-vaccinated calves developed IBK. Only 8 of 12 calves (67%) vaccinated with a bacterin containing a REA of 0.09 remained free of IBK. In a larger field efficacy test consisting of 32 herds in six states, the incidence of IBK in individual herds ranged from 0% to 55%. The overall rate of infection was 11.2%. Vaccination of calves with an M. bovis bacterin that contained a REA of 0.63 reduced the incidence of IBK from 11.2% (217/1931) in the non-vaccinated controls to 4

  7. In-Vivo Slit Scanning Confocal Microscopy of Normal Corneas in Indian Eyes

    Directory of Open Access Journals (Sweden)

    Vanathi Murugesan

    2003-01-01

    Full Text Available Objective: To study the cellular populations of healthy corneas of Indian eyes using confocal microscopy and to evaluate the correlation with age, gender and laterality. Methods: The central corneas of 100 eyes of 50 healthy subjects were examined using an i n-vivo slit scanning confocal microscope (Confoscan 2. Images were analysed for cell densities of the epithelium, stroma and endothelium. Results: Good quality images enabling analysis of all cell layer populations were obtained in 74 eyes of 43 healthy subjects (22 males and 21 females with a mean age of 31.89 ± 13.47 (range 19-71 years. The basal epithelial cell density was 3601.38 ± 408.19 cells/mm2 (range 3017.3 -4231.1cells/mm2. The mean keratocyte nuclei density in the anterior stroma was 1005.02 ± 396.86 cells/mm2 (range 571.6 - 1249.6 cells/mm2 and in the posterior stroma was 654.32 ± 147.09 cells/mm2 (range 402.6 - 1049.1 cells/mm2. Posterior keratocyte nuclei density was 30.76% less than the anterior stromal keratocyte nuclei density. The difference in keratocyte nuclei density was statistically significant (P=0.001. The mean endothelial cell density was 2818.1 ± 361.03 cells/mm2 (range 2118.9 - 4434 cells/mm2 and the mean endothelial cell area was found to be 385.44 ± 42.66 mm2 (range 268.9 - 489.2 mm2. Hexagonal cells formed 22.5 - 69.4% of the endothelial cell populations (mean 42.04 ± 11.81%. Mean coefficient of cell size variation was 32.29 ± 3.06 (range 27.2 - 39.2. No statistically significant differences were found in cell densities of any corneal layer either between female and male patients or between right and left eyes. Basal epithelial cell density, anterior stromal keratocyte nuclei and posterior stromal keratocyte nuclei density were unaffected by age (r= 0.12, 0.07, - 0.12 respectively (P= 0.001. There was a statistically significant negative correlation between mean endothelial cell density and increase in age (r= - 0.42, P=0.001. Coefficient of cell size

  8. Keratinocyte Growth Factor-2 on the Proliferation of Corneal Epithelial Stem Cells in Rabbit Alkali Burned Cornea

    Institute of Scientific and Technical Information of China (English)

    Liu; Yongping; Shuqi; Huang; Jianxian; Lin; Wenxin; Zhang

    2007-01-01

    Purpose: To determine whether the topical application of keratinocyte growth factor-2 (KGF-2) can enhance corneal epithelial healing in rabbit alkali burned cornea. In addition, the distribution and proliferation of corneal epithelial stem cells in KGF-2-treated and control corneas were investigated to explain their mechanisms of effects on the epithelium.Methods: Twenty-four New Zealand eyes were divided into four groups, treated with KGF-2 solution (1, 50, 100 μg/ml) and PBS solution. Eighth millimeter filter paper discs, produced by standard paper punch, were soaked for 15 sec in 0.5N NaOH solution. The alkali-soaked discs were applied to the central cornea, centered on the pupil and held gently in position with forceps for 1 min. The cornea was finally irrigated over 1 min with 100 ml balanced salt solution (BSS). Keratinocyte growth factor-2 was then applied topically three times a day. The phosphate-buffered saline (PBS) group was served as a control. Each corneal epithelial defect was subsequently photographed every 24 hours with a slit lamp and was measured by computer-assisted digitizer. In each group, two rabbits were sacrificed for light microscopic examination after the interval of 7, 14 and 21 days. Meanwhile, the cornea epithelium was examined by immunohistochemistry for P63, AE5, EGFR.Results: Topical application of 10 μg/ml to 100 μg/ml KGF-2 significantly accelerated corneal epithelial wound healing when compared with controls. After 24 hours,epithelial healing rate of the 100 μg/ml KGF-2 group and the PBS treated group was (74±6)% and (40±8)% (P < 0.05). After 48 hours, the rate of the C group was (94±6)%, whereas in the control group it was (73±12)% (P < 0.05). Epithelial defects were often recurrent, which happened only two times in the 100 μg/ml KGF-2-treated group, but many times in the control group. In the corneal epithelial stem cell analysis, the number of the P63 positive cells was higher in the KGF-2-treated corneal

  9. Oxidative Stress to the Cornea, Changes in Corneal Optical Properties, and Advances in Treatment of Corneal Oxidative Injuries

    Directory of Open Access Journals (Sweden)

    Cestmir Cejka

    2015-01-01

    Full Text Available Oxidative stress is involved in many ocular diseases and injuries. The imbalance between oxidants and antioxidants in favour of oxidants (oxidative stress leads to the damage and may be highly involved in ocular aging processes. The anterior eye segment and mainly the cornea are directly exposed to noxae of external environment, such as air pollution, radiation, cigarette smoke, vapors or gases from household cleaning products, chemical burns from splashes of industrial chemicals, and danger from potential oxidative damage evoked by them. Oxidative stress may initiate or develop ocular injury resulting in decreased visual acuity or even vision loss. The role of oxidative stress in the pathogenesis of ocular diseases with particular attention to oxidative stress in the cornea and changes in corneal optical properties are discussed. Advances in the treatment of corneal oxidative injuries or diseases are shown.

  10. Magic angle-enhanced MRI of fibrous microstructures in sclera and cornea with and without intraocular pressure loading.

    Science.gov (United States)

    Ho, Leon C; Sigal, Ian A; Jan, Ning-Jiun; Squires, Alexander; Tse, Zion; Wu, Ed X; Kim, Seong-Gi; Schuman, Joel S; Chan, Kevin C

    2014-08-07

    The structure and biomechanics of the sclera and cornea are central to several eye diseases such as glaucoma and myopia. However, their roles remain unclear, partly because of limited noninvasive techniques to assess their fibrous microstructures globally, longitudinally, and quantitatively. We hypothesized that magic angle-enhanced magnetic resonance imaging (MRI) can reveal the structural details of the corneoscleral shell and their changes upon intraocular pressure (IOP) elevation. Seven ovine eyes were extracted and fixed at IOP = 50 mm Hg to mimic ocular hypertension, and another 11 eyes were unpressurized. The sclera and cornea were scanned at different angular orientations relative to the main magnetic field inside a 9.4-Tesla MRI scanner. Relative MRI signal intensities and intrinsic transverse relaxation times (T2 and T2*) were determined to quantify the magic angle effect on the corneoscleral shells. Three loaded and eight unloaded tendon samples were scanned as controls. At magic angle, high-resolution MRI revealed distinct scleral and corneal lamellar fibers, and light/dark bands indicative of collagen fiber crimps in the sclera and tendon. Magic angle enhancement effect was the strongest in tendon and the least strong in cornea. Loaded sclera, cornea, and tendon possessed significantly higher T2 and T2* than unloaded tissues at magic angle. Magic angle-enhanced MRI can detect ocular fibrous microstructures without contrast agents or coatings and can reveal their MR tissue property changes with IOP loading. This technique may open up new avenues for assessment of the biomechanical and biochemical properties of ocular tissues in aging and in diseases involving the corneoscleral shell. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  11. Magic Angle–Enhanced MRI of Fibrous Microstructures in Sclera and Cornea With and Without Intraocular Pressure Loading

    Science.gov (United States)

    Ho, Leon C.; Sigal, Ian A.; Jan, Ning-Jiun; Squires, Alexander; Tse, Zion; Wu, Ed X.; Kim, Seong-Gi; Schuman, Joel S.; Chan, Kevin C.

    2014-01-01

    Purpose. The structure and biomechanics of the sclera and cornea are central to several eye diseases such as glaucoma and myopia. However, their roles remain unclear, partly because of limited noninvasive techniques to assess their fibrous microstructures globally, longitudinally, and quantitatively. We hypothesized that magic angle–enhanced magnetic resonance imaging (MRI) can reveal the structural details of the corneoscleral shell and their changes upon intraocular pressure (IOP) elevation. Methods. Seven ovine eyes were extracted and fixed at IOP = 50 mm Hg to mimic ocular hypertension, and another 11 eyes were unpressurized. The sclera and cornea were scanned at different angular orientations relative to the main magnetic field inside a 9.4-Tesla MRI scanner. Relative MRI signal intensities and intrinsic transverse relaxation times (T2 and T2*) were determined to quantify the magic angle effect on the corneoscleral shells. Three loaded and eight unloaded tendon samples were scanned as controls. Results. At magic angle, high-resolution MRI revealed distinct scleral and corneal lamellar fibers, and light/dark bands indicative of collagen fiber crimps in the sclera and tendon. Magic angle enhancement effect was the strongest in tendon and the least strong in cornea. Loaded sclera, cornea, and tendon possessed significantly higher T2 and T2* than unloaded tissues at magic angle. Conclusions. Magic angle–enhanced MRI can detect ocular fibrous microstructures without contrast agents or coatings and can reveal their MR tissue property changes with IOP loading. This technique may open up new avenues for assessment of the biomechanical and biochemical properties of ocular tissues in aging and in diseases involving the corneoscleral shell. PMID:25103267

  12. The role of connective tissue growth factor, transforming growth factor β1 and Smad signaling pathway in cornea wound healing

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The cornea is a highly specialized and unique organ in the human body. Its main function is to project light from the external environment onto the retina, and it has a specific transparency to perform its function properly. The transparency and integrity of the cornea is of vital importance. The corneal wound, especially laceration deep to Bowman's membrane and stroma, which will inevitably cause scar formation, may cause the degeneration or even loss of sight. Injury can activate many biological factors in cornea as a strong stimulating signal. Transforming growth factors (TGF) and connective tissue growth factors (CTGF) are thought to be related to scar formation after injury. TGF can stimulate stroma cells of cornea and promote synthesis of matrix. Over expression of TGF causes scar formation.1,2 CTGF is a 38 kD cysteine-rich protein molecule and belongs to CCN family (CTGF/Fisp12, Cyr 61/CEF-10, Nov). In 1991, CTGF was firstly found in endothelial cells of human umbilical vein cultured in vitro.3,4 CTGF acts as an important molecule that intermediates the processes of fibrosis, scarring, wound repairing, angiogenesis and embryonic development in many cell types. CTGF plays a unique role in proliferation, differentiation and adhesion of fibroblast cells, which in turn produces large amounts of collagen and other extracellular matrix (ECM) proteins.5-8 CTGF is upregulated in fibrotic diseases, including lung-, skin-, pancreas-, liver-and kidney fibrosis.9,10 This study reports the expressions and interactions of TGF-β1 and CTGF in corneal wound in vivo. This study aimed at determining the expressions and interactions of CTGF and TGF-β1 in Smad signaling pathway during the period when corneal wound was healing.

  13. Comment on amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis

    Institute of Scientific and Technical Information of China (English)

    Ahmet; Tas; Abdullah; Ilhan; Umit; Yolcu; Uzeyir; Erdem

    2015-01-01

    <正>Dear Editor,We congratulate Zeng et al[1]for their study entitled"Amniotic membrane covering promotes healing of cornea epithelium and improves visual acuity after debridement for fungal keratitis".The authors endeavored to present an alternative method for ophthalmologists in the treatment of a challenging case.We would like to express our reservations and ask for the attitudes of the authors about

  14. Commercially available rigid gas-permeable contact lens for protecting the cornea from drying during vitrectomy with a wide viewing system

    OpenAIRE

    Kamei M; Matsumura N; Sakaguchi H; Oshima Y; Ikuno Y; Nishida K

    2012-01-01

    Motohiro Kamei, Nagakazu Matsumura, Hirokazu Sakaguchi, Yusuke Oshima, Yasushi Ikuno, Kohji NishidaDepartment of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, JapanPurpose: We evaluated the usefulness of commercially available materials for protecting the cornea from drying during vitrectomy with a wide-angle viewing system.Methods: Three vitreoretinal surgeons evaluated fundus visibility during vitrectomy on the images of five study materials used on the cornea: balance...

  15. Enrichment of pathogenic alleles in the brittle cornea gene, ZNF469, in keratoconus

    Science.gov (United States)

    Lechner, Judith; Porter, Louise F.; Rice, Aine; Vitart, Veronique; Armstrong, David J.; Schorderet, Daniel F.; Munier, Francis L.; Wright, Alan F.; Inglehearn, Chris F.; Black, Graeme C.; Simpson, David A.; Manson, Forbes; Willoughby, Colin E.

    2014-01-01

    Keratoconus, a common inherited ocular disorder resulting in progressive corneal thinning, is the leading indication for corneal transplantation in the developed world. Genome-wide association studies have identified common SNPs 100 kb upstream of ZNF469 strongly associated with corneal thickness. Homozygous mutations in ZNF469 and PR domain-containing protein 5 (PRDM5) genes result in brittle cornea syndrome (BCS) Types 1 and 2, respectively. BCS is an autosomal recessive generalized connective tissue disorder associated with extreme corneal thinning and a high risk of corneal rupture. Some individuals with heterozygous PRDM5 mutations demonstrate a carrier ocular phenotype, which includes a mildly reduced corneal thickness, keratoconus and blue sclera. We hypothesized that heterozygous variants in PRDM5 and ZNF469 predispose to the development of isolated keratoconus. We found a significant enrichment of potentially pathologic heterozygous alleles in ZNF469 associated with the development of keratoconus (P = 0.00102) resulting in a relative risk of 12.0. This enrichment of rare potentially pathogenic alleles in ZNF469 in 12.5% of keratoconus patients represents a significant mutational load and highlights ZNF469 as the most significant genetic factor responsible for keratoconus identified to date. PMID:24895405

  16. Clinical Correlation between Placido, Scheimpflug and LED Color Reflection Topographies in Imaging of a Scarred Cornea

    Directory of Open Access Journals (Sweden)

    Anastasios John Kanellopoulos

    2014-10-01

    Full Text Available This case report aims to evaluate safety, efficacy and feasibility of anterior surface imaging by a novel point-source reflection topographer, in comparison to four other corneal imaging modalities. A 17-year-old female patient, clinically diagnosed with chronic herpetic keratitis in her left eye was imaged by a novel multicolored-spot reflection topography system. We comparatively investigated elevation and curvature maps between the novel topographer and established Placido disk topography and Scheimpflug tomography systems. Pachymetry maps were compared between the Scheimpflug system and anterior-segment optical coherence tomography system. The Placido system failed to properly register the abnormal anterior surface due to incomplete mire registration, while the Scheimpflug topometry device imaged the anterior surface properly, but not the posterior (due to media opacity, and thus pachymetry was highly irregular and erroneous in this case. Imaging of corneas infected with herpes simplex virus keratitis has been rare; we have not identified any such documentation in the peer review literature in the last 10 years. This novel multicolored-spot reflection topography imaging may offer successful corneal imaging in cases where established clinical topography systems may fail to produce accurate reconstruction of the corneal shape. This is an important case demonstrating exceptional clinical feasibility in such rare cases offered by a newly introduced technology in ophthalmic imaging.

  17. Precut cornea for Descemet's stripping endothelial keratoplasty: experience at a single eye bank.

    Science.gov (United States)

    Mohamed, Ashik; Chaurasia, Sunita; Chandragiri, Venkataswamy; Kandhibanda, Srinivas; Gunnam, Srinivas; Garg, Prashant

    2016-07-20

    The aim of the study is to describe the experience with precut facility for endothelial keratoplasty at a single eye bank affiliated to a tertiary eye care center in India. Data on precut tissues from Nov 2012 to Dec 2014 were retrospectively reviewed from the electronic database of the eye bank of a tertiary eye care center in South India. Donor characteristic data including donor age, precut and postcut endothelial cell density (ECD), recipient age, and thickness of graft were collected. The number of precuts increased from 42 in 2012 (Nov and Dec) and 422 in 2013 to 584 in 2014. Of the total of 1048 precuts, seven (0.67 %) were miscut and could not be utilized for transplants. The donor age ranged from 2 to 89 years. A mean change of 43.6 ± 325.2 cells/mm(2) in ECD was noted after cut, proportional increase in mean being 1.9 %. The change in ECD after cut was negatively correlated with ECD before cut. The recipient age ranged from 1 to 89 years. The median thickness of donor lenticule after cut was 148 µm (interquartile range 131-166 µm). Analysis of precut donor corneas from a single eye bank shows that the ECD of the processed tissues was excellent for transplantation. The tissue wastage in the hands of eye bank personal was minimal.

  18. Why don't we have enough cornea donors? A literature review and survey.

    Science.gov (United States)

    Golchet, G; Carr, J; Harris, M G

    2000-05-01

    Organ donation provides a second chance for those who have experienced severe disease or injury. Unfortunately there is a huge discrepancy between the supply and demand of transplantable organs, despite the existence of sufficient numbers of potential donors. Through a review of the literature and a survey of optometry students, this article provides insight into the reasons for the shortage of corneal donors and how more corneal donors might be obtained. A survey of 200 optometry students at the University California, Berkeley, School of Optometry was conducted to augment the literature review. Seventy-six students (38% of those surveyed) completed the survey process. Results of the survey indicated that 64.5% of who responded were willing to donate body organs, while 31.6% were not. Of those not willing to donate organs, 11.8% cited religious reasons. Other personal reasons included: fear (4%), respect for the human body (7.9%), and parental disapproval (6.4%). Only 46.1% of respondents had donation stickers on their driver's licenses. The literature review and survey indicate that age, religion, culture, personality characteristics, views on death and mortality, body image, and humanitarian concerns are among the many factors that influence people's opinion concerning organ donations. Education of the public and health care professionals' awareness of the importance of obtaining corneas for donation is crucial to end the shortage of organ donors.

  19. Q pili enhance the attachment of Moraxella bovis to bovine corneas in vitro.

    Science.gov (United States)

    Ruehl, W W; Marrs, C; Beard, M K; Shokooki, V; Hinojoza, J R; Banks, S; Bieber, D; Mattick, J S

    1993-01-01

    Moraxella bovis, the causative agent of infectious bovine keratoconjunctivitis, exhibits several virulence factors, including pili, haemolysin, leukotoxin, and proteases. The pili are filamentous appendages which mediate bacterial adherence. Prior studies have shown that Q-piliated M. bovis Epp63 are more infectious and more pathogenic than I-piliated and non-piliated isogenic variants, suggesting that Q pili per se, or traits associated with Q-pilin expression, promote the early association of Q-piliated bacteria with bovine corneal tissue. In order to better evaluate the role of Q pili in M. bovis attachment, several M. bovis strains and a recombinant P. aeruginosa strain which elaborates M. bovis Q pili but not P. aeruginosa PAK pili, were evaluated using an in vitro corneal attachment assay. For each strain tested, piliated organisms attached better than non-piliated bacteria. M. bovis Epp63 Q-piliated bacteria adhered better than either the I-piliated or non-piliated isogenic variants. Finally, recombinant P. aeruginosa organisms elaborating M. bovis Q pili adhered better than the parent P. aeruginosa strain which did not produce M. bovis pili. These results indicate that the presence of pili, especially Q pili, enhances the attachment of bacteria to bovine cornea in vitro.

  20. Examination of tear film smoothness on corneae after refractive surgeries using a noninvasive interferometric method

    Science.gov (United States)

    Szczesna, Dorota H.; Kulas, Zbigniew; Kasprzak, Henryk T.; Stenevi, Ulf

    2009-11-01

    A lateral shearing interferometer was used to examine the smoothness of the tear film. The information about the distribution and stability of the precorneal tear film is carried out by the wavefront reflected from the surface of tears and coded in interference fringes. Smooth and regular fringes indicate a smooth tear film surface. On corneae after laser in situ keratomileusis (LASIK) or radial keratotomy (RK) surgery, the interference fringes are seldom regular. The fringes are bent on bright lines, which are interpreted as tear film breakups. The high-intensity pattern seems to appear in similar location on the corneal surface after refractive surgery. Our purpose was to extract information about the pattern existing under the interference fringes and calculate its shape reproducibility over time and following eye blinks. A low-pass filter was applied and correlation coefficient was calculated to compare a selected fragment of the template image to each of the following frames in the recorded sequence. High values of the correlation coefficient suggest that irregularities of the corneal epithelium might influence tear film instability and that tear film breakup may be associated with local irregularities of the corneal topography created after the LASIK and RK surgeries.

  1. Novel GLA Deletion in a Cypriot Female Presenting with Cornea Verticillata

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    Theodoros Georgiou

    2016-01-01

    Full Text Available Fabry disease is an X-linked lysosomal storage disorder resulting from a deficiency of the hydrolytic enzyme α-galactosidase A (α-Gal-A. It is characterized by progressive lysosomal accumulation of globotriaosylceramide (Gb3 and multisystem pathology, affecting the skin, nervous and cerebrovascular systems, kidneys, and heart. Heterozygous females typically exhibit milder symptoms and a later age of onset than males. Rarely, they may be relatively asymptomatic throughout a normal life span or may have symptoms as severe as those observed in males with the classic phenotype. We report on a 17-year-old female in whom cornea verticillata was found during a routine ophthalmological examination but with no other clinical symptoms. Leucocyte α-galactosidase activity was within the overlap range between Fabry heterozygotes and normal controls. Sanger sequencing of the GLA gene failed to reveal any pathogenic variants. Multiplex Ligation-dependent Probe Amplification (MLPA analysis revealed a deletion of exon 7. Using a long-range PCR walking approach, we managed to identify the deletion breakpoints. The deletion spans 1182 bp, with its 5′ end located within exon 6 of the GLA gene and its 3′ end located 612 bp downstream of exon 7. This finding represents a novel deletion identified in the first reported Cypriot female carrier of Fabry disease.

  2. Feasibility of quantitatively diagnosing cornea infection using Raman spectroscopy (Conference Presentation)

    Science.gov (United States)

    Bai, Yanru; Chen, Keren; Mishra, Arti; Beuerman, Roger; Liu, Quan

    2017-02-01

    Ocular infection is a serious eye disease that could lead to blindness without prompt and proper treatment. In pathology, ocular infection is caused by microorganisms such as bacteria, fungi or viruses. The essential prerequisite for the optimal treatment of ocular infection is to identify the microorganism causing infection early as each type of microorganism requires a different therapeutic approach. The clinical procedure for identifying the microorganism species causing ocular infection includes Gram staining (for bacteria)/microscopy (for fungi) and the culture of corneal surface scraping, or aqueous and vitreous smear samples taken from the surface of infected eyes. The culture procedure is labor intensive and expensive. Moreover, culturing is time consuming, which usually takes a few days or even weeks. Such a long delay in diagnosis could result in the exacerbation of patients' symptoms, the missing of the optimal time frame for initiating treatment and subsequently the rising cost for disease management. Raman spectroscopy has been shown highly effective for non-invasive identification of both fungi and bacteria qualitatively. In this study, we investigate the feasibility of identifying the microorganisms of ocular infection and quantifying the concentrations using Raman spectroscopy by measuring not only gram negative and gram positive bacteria but also infected cornea. By applying a modified orthogonal projection approach, the relative concentration of each bacteria species could be quantified. Our results indicate the great potential of Raman spectroscopy as an alternative tool for non-invasive diagnosis of ocular infection and could play a significantly role in future ophthalmology.

  3. Enrichment of pathogenic alleles in the brittle cornea gene, ZNF469, in keratoconus.

    Science.gov (United States)

    Lechner, Judith; Porter, Louise F; Rice, Aine; Vitart, Veronique; Armstrong, David J; Schorderet, Daniel F; Munier, Francis L; Wright, Alan F; Inglehearn, Chris F; Black, Graeme C; Simpson, David A; Manson, Forbes; Willoughby, Colin E

    2014-10-15

    Keratoconus, a common inherited ocular disorder resulting in progressive corneal thinning, is the leading indication for corneal transplantation in the developed world. Genome-wide association studies have identified common SNPs 100 kb upstream of ZNF469 strongly associated with corneal thickness. Homozygous mutations in ZNF469 and PR domain-containing protein 5 (PRDM5) genes result in brittle cornea syndrome (BCS) Types 1 and 2, respectively. BCS is an autosomal recessive generalized connective tissue disorder associated with extreme corneal thinning and a high risk of corneal rupture. Some individuals with heterozygous PRDM5 mutations demonstrate a carrier ocular phenotype, which includes a mildly reduced corneal thickness, keratoconus and blue sclera. We hypothesized that heterozygous variants in PRDM5 and ZNF469 predispose to the development of isolated keratoconus. We found a significant enrichment of potentially pathologic heterozygous alleles in ZNF469 associated with the development of keratoconus (P = 0.00102) resulting in a relative risk of 12.0. This enrichment of rare potentially pathogenic alleles in ZNF469 in 12.5% of keratoconus patients represents a significant mutational load and highlights ZNF469 as the most significant genetic factor responsible for keratoconus identified to date.

  4. Birefringence of the central cornea in children assessed with scanning laser polarimetry

    Science.gov (United States)

    Irsch, Kristina; Shah, Ashesh A.

    2012-08-01

    Corneal birefringence is a well-known confounding factor with all polarization-sensitive technology used for retinal scanning and other intraocular assessment. It has been studied extensively in adults, but little is known regarding age-related differences. Specifically, no information is available concerning corneal birefringence in children. For applications that are geared towards children, such as retinal birefringence scanning for strabismus screening purposes, it is important to know the expected range of both corneal retardance and azimuth in pediatric populations. This study investigated central corneal birefringence in children (ages three and above), by means of scanning laser polarimetry (GDx-VCC™, Carl Zeiss Meditec, Inc.). Children's measures of corneal retardance and azimuth were compared with those obtained in adults. As with previous studies in adults, corneal birefringence was found to vary widely in children, with corneal retardance ranging from 10 to 77 nm, and azimuth (slow axis) ranging from -11° to 71° (measured nasally downward). No significant differences in central corneal birefringence were found between children and adults, nor were significant age-related differences found in general. In conclusion, establishing knowledge of the polarization properties of the central cornea in children allows better understanding, exploitation, or bypassing of these effects in new polarization-sensitive pediatric ophthalmic applications.

  5. The surgical repair of the cornea of the dog using pericardium as a keratoprosthesis

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    Paulo Sérgio de Moraes Barros

    1995-12-01

    Full Text Available Significant advances in corneal repair have been made in the past. Tissue graft has been used to repair full-thickness defects of the cornea and sclera. Equine pericardium preserved in glycerol was used to repair full-thickness corneal lesions after limbal melanoma excision and corneal wound with iris prolapse. A six-year old male, German Shepherd, with 1 cm of diameter, dark-pigmented mass at the temporal limbus of the right eye, with two months of evolution, and a four month old female mixed breed dog, with a corneal wound and iris prolapse, in the left eye, secondary to a cat scratch 5 days earlier. In both cases a piece of pericardium was sutured close to the corneal defects. An antibiotic ointment and atropine 1% eye drops were used. The intraocular pressure was low in the following days, but arose to normal values. All other structures were normal. A granulation tissue initially grew near the patch, and the opacity of the pericardium remained. Dexamethasone eye drops and ointment were used, and the granulation tissue disappeared two months after surgery. Eighteen months follow-up showed the eyes in good condition, although opaqueness was still present.

  6. Corneal biomechanical data and biometric parameters measured with Scheimpflug-based devices on normal corneas

    Science.gov (United States)

    Nemeth, Gabor; Szalai, Eszter; Hassan, Ziad; Lipecz, Agnes; Flasko, Zsuzsa; Modis, Laszlo

    2017-01-01

    AIM To analyze the correlations between ocular biomechanical and biometric data of the eye, measured by Scheimpflug-based devices on healthy subjects. METHODS Three consecutive measurements were carried out using the corneal visualization Scheimpflug technology (CorVis ST) device on healthy eyes and the 10 device-specific parameters were recorded. Pentacam HR-derived parameters (corneal curvature radii on the anterior and posterior surfaces; apical pachymetry; corneal volume; corneal aberration data; depth, volume and angle of the anterior chamber) and axial length (AL) from IOLMaster were correlated with the 10 specific CorVis ST parameters. RESULTS Measurements were conducted in 43 eyes of 43 volunteers (age 61.24±15.72y). The 10 specific CorVis ST data showed significant relationships with corneal curvature radii both on the anterior and posterior surface, pachymetric data, root mean square (RMS) data of lower-order aberrations, and posterior RMS of higher-order aberrations and spherical aberration of the posterior cornea. Anterior chamber depth showed a significant relationship, but there were no significant correlations between corneal volume, anterior chamber volume, mean chamber angle or AL and the 10 specific CorVis ST parameters. CONCLUSIONS CorVis ST-generated parameters are influenced by corneal curvature radii, some corneal RMS data, but corneal volume, anterior chamber volume, chamber angle and AL have no correlation with the biomechanical parameters. The parameters measured by CorVis ST seem to refer mostly to corneal properties of the eye. PMID:28251079

  7. Birefringence of the central cornea in children assessed with scanning laser polarimetry.

    Science.gov (United States)

    Irsch, Kristina; Shah, Ashesh A

    2012-08-01

    Corneal birefringence is a well-known confounding factor with all polarization-sensitive technology used for retinal scanning and other intraocular assessment. It has been studied extensively in adults, but little is known regarding age-related differences. Specifically, no information is available concerning corneal birefringence in children. For applications that are geared towards children, such as retinal birefringence scanning for strabismus screening purposes, it is important to know the expected range of both corneal retardance and azimuth in pediatric populations. This study investigated central corneal birefringence in children (ages three and above), by means of scanning laser polarimetry (GDx-VCC™, Carl Zeiss Meditec, Inc.). Children's measures of corneal retardance and azimuth were compared with those obtained in adults. As with previous studies in adults, corneal birefringence was found to vary widely in children, with corneal retardance ranging from 10 to 77 nm, and azimuth (slow axis) ranging from -11° to 71° (measured nasally downward). No significant differences in central corneal birefringence were found between children and adults, nor were significant age-related differences found in general. In conclusion, establishing knowledge of the polarization properties of the central cornea in children allows better understanding, exploitation, or bypassing of these effects in new polarization-sensitive pediatric ophthalmic applications.

  8. Effect of In Vitro Transcorneal Approach of Aceclofenac Eye Drops through Excised Goat, Sheep, and Buffalo Corneas

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    Vivek Dave

    2015-01-01

    Full Text Available The current study involves the evaluation of factors that influence the transcorneal permeation of aqueous drops of aceclofenac ophthalmic formulation through freshly excised goat, sheep, and buffalo corneas. Aceclofenac formulation with different concentrations 0.1–0.5% (w/v and with different pH and different preservatives, was taken into account. The amount of drug permeated from different formulations was estimated using an Franz diffusion cell. A linear increase in drug permeation was observed with increase in pH (5.5 to 7.4. The apparent permeability coefficient was found to be maximum 15.01±0.45 on goat cornea and maximum transport of aceclofenac was observed at physiological pH of tears (i.e., 7. The results advocate that aceclofenac 0.5% (w/v ophthalmic solution (pH 7.0 containing BAK (0.01% provides maximum in vitro ocular permeability through goat, sheep, and buffalo corneas.

  9. Structure and function of the retinal pigment epithelium, photoreceptors and cornea in the eye of Sardinella aurita (Clupeidae, Teleostei

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    Mostafa Ali Salem

    2016-05-01

    Full Text Available The structure of the pigment epithelium, photoreceptors and the cornea in the eye of a teleost, Sardinella aurita was examined by light and electron microscopy. The retinal pigment epithelium forms a single layer of cells joined laterally by cell junctions. Centrally in the retina these cells are columnar, while more peripherally they become cuboidal in shape. The basal (scleral border of the pigment epithelial cells is not infolded but is relatively smooth. Phagosomes containing lysosome-like bodies are also common features of the retinal pigment epithelium. Numerous melanosomes (pigment granules are abundant throughout the epithelial cells. These melanosomes probably absorb light which has passed through the photoreceptor layer. Four photoreceptor cells were identified; rods, long single cones, short single cones and double cones. The presence of these types suggests a diversity of photoreceptor function. Square mosaic pattern of cones and well-developed choroid gland are also main features of the eye. The inner segment of rods and cones were rich in organelles indicating much synthetic activity. Calycal processes projecting from cone outer segments are also observed. The cornea includes an epithelium with a complex pattern of surface microplicae, a basement membrane, dermal stroma, an iridescent layer, scleral stroma, Descemet’s membrane and endothelium. The autochthonous layer which is seen in some teleosts has not been observed in the cornea of this species. These and other observations were discussed in relation to the photic environment and habits of this fish.

  10. Observation on ultrastructure and histopathology of cornea following femtosecond laser-assisted deep lamellar keratoplasty for acute corneal alkaline burns.

    Science.gov (United States)

    Li, Wen-Jing; Hu, Yu-Kun; Song, Hui; Gao, Xiao-Wei; Zhao, Xu-Dong; Dong, Jing; Guo, Yun-Lin; Cai, Yan

    2016-01-01

    To demonstrate the changes in ultrastructure and histopathology of the cornea in acute corneal alkaline burns after femtosecond laser-assisted deep lamellar keratoplasty. The New Zealand white rabbits treated with alkaline corneal burn were randomized into two groups, Group A (16 eyes) with femtosecond laser-assisted deep lamellar keratoplasty 24h after burn and Group B (16 eyes) without keratoplasty as controls. All eyes were evaluated with transmission electron microscopy (TEM) at 1, 2, 3, and 4wk follow-up, then all corneas were tested by hematoxylin and eosin staining histology. The corneal grafts in Group A were transparent, while those in Group B showed corneal stromal edema and loosely arranged collagen fibers. One week after treatment, TEM revealed the intercellular desmosomes in the epithelial layers and intact non-dissolving nuclei in Group A. At week 4, the center of the corneas in Group A was transparent with regularly arranged collagen fibers and fibroblasts in the stroma. In Group B, squamous cells were observed on the corneal surface and some epithelial cells were detached. Femtosecond laser-assisted deep lamellar keratoplasty can suppress inflammatory responses, prevent toxic substance-induced injury to the corneal endothelium and inner tissues with quicker recovery and better visual outcomes.

  11. Preparation of pre-cut corneas from fresh donated whole globes for Descemet's stripping automated keratoplasty: 3-year results at the Central Eye Bank of Iran.

    Science.gov (United States)

    Kanavi, Mozhgan Rezaei; Javadi, Mohammad Ali; Javadi, Fatemeh; Chamani, Tahereh

    2014-09-01

    To describe the technique and the results of the preparation of pre-cut corneas for Descemet's stripping automated endothelial keratoplasty (DSAEK) during a 3-year period at the Central Eye Bank of Iran (CEBI). The method of preparation of pre-cut corneas from donated whole globes at the CEBI is described and the frequency and percentage of pre-cut corneas prepared for DSAEK, between April 2009 and March 2012, are specified. Moreover, post-operative reports are reviewed for any complaints about using pre-cut tissues for DSAEK. Out of the 1,518 donated whole globes appropriate for DSAEK, 1,478 (97.4 %) pre-cut corneas were successfully prepared. The method of preparation failed in 40 (2.6 %) cases. Based on the eye bank post-operative reports, thickness of pre-cut tissues for DSAEK was deemed unacceptable in only 6 (0.4 %) cases prior to surgery; five of these were too thick and one was too thin. Preparation of pre-cut corneas, for DSAEK from donated whole globes, in the CEBI is a safe and easy method, with very good preservation of endothelial cells after the preparation of the pre-cut corneas and reduced risks from corneal manipulation.

  12. A short-term study of corneal collagen cross-linking with hypo-osmolar riboflavin solution in keratoconic corneas

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    Shao-Feng Gu

    2015-02-01

    Full Text Available AIM: To report the 3mo outcomes of collagen cross-linking (CXL with a hypo-osmolar riboflavin in thin corneas with the thinnest thickness less than 400 μm without epithelium. METHODS: Eight eyes in 6 patients with age 26.2±4.8y were included in the study. All patients underwent CXL using a hypo-osmolar riboflavin solution after its de-epithelization. Best corrected visual acuity, manifest refraction, the thinnest corneal thickness, and endothelial cell density were evaluated before and 3mo after the procedure. RESULTS: The mean thinnest thickness of the cornea was 408.5±29.0 μm before treatment and reduced to 369.8±24.8 μm after the removal of epithelium. With the application of the hypo-osmolar riboflavin solution, the thickness increased to 445.0±26.5 μm before CXL and recover to 412.5±22.7 μm at 3mo after treatment, P=0.659. Before surgery, the mean K-value of the apex of the keratoconus corneas was 57.6±4.0 diopters, and slightly decreased (54.7±4.9 diopters after surgery (P=0.085. Mean best-corrected visual acuity was 0.55±0.23 logarithm of the minimal angle of resolution, and increased to 0.53±0.26 logarithm after surgery (P=0.879. The endothelial cell density was 2706.4±201.6 cells/mm2 before treatment, and slightly decreased (2641.2±218.2 cells/mm2 at last fellow up (P=0.002. CONCLUSION: Corneal collagen cross-linking with a hypo-osmolar riboflavin in thin corneas seems to be a promising treatment. Further study should be done to evaluate the safety and efficiency of CXL in thin corneas for the long-term.

  13. A short-term study of corneal collagen cross-linking with hypo-osmolar riboflavin solution in keratoconic corneas

    Institute of Scientific and Technical Information of China (English)

    Shao-Feng; Gu; Zhao-Shan; Fan; Li-Hua; Wang; Xiang-Chen; Tao; Yong; Zhang; Chun-Qin; Wang; Ya; Wang; Guo-Ying; Mu

    2015-01-01

    AIM: To report the 3mo outcomes of collagen crosslinking(CXL) with a hypo-osmolar riboflavin in thin corneas with the thinnest thickness less than 400 μm without epithelium.METHODS: Eight eyes in 6 patients with age 26.2±4.8y were included in the study. All patients underwent CXL using a hypo-osmolar riboflavin solution after its de-epithelization. Best corrected visual acuity, manifest refraction, the thinnest corneal thickness, and endothelial cell density were evaluated before and 3mo after the procedure.RESULTS: The mean thinnest thickness of the cornea was 408.5 ±29.0 μm before treatment and reduced to369.8 ±24.8 μm after the removal of epithelium. With the application of the hypo-osmolar riboflavin solution, the thickness increased to 445.0 ±26.5 μm before CXL and recover to 412.5 ±22.7 μm at 3mo after treatment, P =0.659). Before surgery, the mean K-value of the apex of the keratoconus corneas was 57.6 ±4.0 diopters, and slightly decreased(54.7±4.9 diopters) after surgery(P =0.085). Mean best-corrected visual acuity was 0.55 ±0.23 logarithm of the minimal angle of resolution, and increased to 0.53±0.26 logarithm after surgery(P =0.879).The endothelial cell density was 2706.4 ±201.6 cells/mm2 before treatment, and slightly decreased( 2641. 2 ±218.2 cells/mm2) at last fellow up(P =0.002).CONCLUSION: Corneal collagen cross-linking with a hypo-osmolar riboflavin in thin corneas seems to be a promising treatment. Further study should be done to evaluate the safety and efficiency of CXL in thin corneas for the long-term.

  14. [Expression of matrix metalloproteinases and inhibitor on the cornea tissue in rabbit after implantation of modified titanium skirt for keratoprosthesis].

    Science.gov (United States)

    Li, Li; Zhou, Dilys; Wang, Xiu-mei; Wang, Xiao-ping; Cui, Fu-zhai; Lu, Yu-jie; Huang, Yi-fei

    2012-01-01

    To investigate the expression of matrix metalloproteinase-2 (MMP-2) and Tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) in rabbit corneas implanted with modified titanium skirt of keratoprosthesis in order to explore the potential roles. A total of 20 New Zealand white rabbits with corneal alkali burn in right eye rabbit corneas were divided into three groups. There were 6 animals in each group. Skirt of hydroxyapatite/Sandblast-Titanium and Sandblast-Titanium were inserted into the corneal stroma of rabbits in group A and group B. The group C did not insert skirt as surgical control.2 rabbits were as normal control D group. A total of 20 New Zealand white rabbits were divided into four groups with the same way. The expression of MMP-2 and TIMP-2 was determined by immunohistochemistry at 1 month, 3 months. The expression of MMP-2 and TIMP-2 mRNA level was determined by real time-polymerase chain reaction, and its protein level was determined by western blot. The optical cylinder was implanted to rabbit corneas, which were implanted with modified titanium skirt after 3 months. There was one case of corneal dissolution being found in group F. MMP-2 and TIMP-2 immunoreactivities were expressed in the normal corneas, predominantly in the corneal epithelium. After injury, immunoreactivities of both MMP-2 and TIMP-2 were increased notably in the healing corneal epithelium, infiltrating inflammatory cells, stromal fibroblasts and in growing vascular endothelial cells. The expression of MMP-2 was lower in group A and E than that in group B and F after 1 month and 3 months (t = 12.05, 2.93, 12.006, 3.781, P 0.05); MMP-2 immunoreactivities were absent or lowly expressed predominantly in the corneal epithelium of normal corneas. The expression of MMP-2, TIMP-2 mRNA level was parallel that of protein level. The expression of MMP-2 was lower in the corneal tissue sections of HA/SB-Ti skirt inserted eyes than that in the tissue sections of SB-Ti skirt inserted eyes. The

  15. Effect of topical fluoroquinolones on the expression of matrix metalloproteinases in the cornea

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    O'Brien Terrence P

    2003-10-01

    Full Text Available Abstract Background Matrix metalloproteinases play an important role in extracellular matrix deposition and degradation. Based on previous clinical observations of corneal perforations during topical fluoroquinolone treatment, we decided to evaluate the comparative effects of various fluoroquinolone eye drops on the expression of matrix metalloproteinases (MMPs in cornea. Methods Eighty female Lewis rats were divided into two experimental groups: intact and wounded corneal epithelium. Uniform corneal epithelial defects were created in the right eye with application of 75% alcohol in the center of the tissue for 6 seconds. The treatment groups were tested as follows: 1 Tear drops: carboxymethylcellulose sodium 0.5 % (Refresh, Allergan; 2 Ciprofloxacin 0.3% (Ciloxan, Alcon; 3 Ofloxacin 0.3%(Ocuflox, Allergan; 4 Levofloxacin 0.5%(Quixin, Santen. Eye drops were administered 6 times a day for 48 hours. Rats were sacrificed at 48 hours. Immunohistochemical analysis and zymography were conducted using antibodies specific to MMPs-1, 2, 8 and 9. Results MMP-1, MMP-2, MMP-8 and MMP-9 expression were detected at 48 hrs in undebrided corneal epithelium groups treated with the topical fluoroquinolones. No statistical difference was observed in quantitative expression of MMPs among ciprofloxacin 0.3%, ofloxacin 0.3%, levofloxacin 0.5%. When the artificial tear group and the fluoroquinolone groups with corneal epithelial defect were compared, increased expression of MMPs was observed as a result of the wound healing process. However, the fluoroquinolone treated group exhibited high statistically significantly levels of MMPs expression. Conclusions Our study provides preliminary evidence that topical application of fluoroquinolone drugs can induce the expression of MMP-1, MMP-2, MMP-8 and MMP-9 in the undebrided corneal epithelium compared to artificial tear eye drops.

  16. Antinociceptive and anti-inflammatory activities of sulphated polysaccharides from the red seaweed Gracilaria cornea.

    Science.gov (United States)

    Coura, Chistiane O; de Araújo, Ianna W F; Vanderlei, Edfranck S O; Rodrigues, José A G; Quinderé, Ana L G; Fontes, Bruno P; de Queiroz, Ismael N L; de Menezes, Dalgimar B; Bezerra, Mirna M; e Silva, Antonio A R; Chaves, Hellíada V; Jorge, Roberta J B; Evangelista, Janaina S A M; Benevides, Norma M B

    2012-04-01

    Seaweeds have attracted special interest as good sources of sulphated polysaccharides (SP) for use in pharmaceutical industries and biotechnology. In this study, we evaluated the effects of SP from the red seaweed Gracilaria cornea (Gc-TSP) in nociceptive and inflammatory models. In mice, Gc-TSP (3, 9 or 27 mg/kg) significantly reduced nociceptive responses, as measured by the number of writhes, at all tested doses. In a formalin test, Gc-TSP significantly reduced licking time in both phases of the test at a dose of 27 mg/kg. In a hot-plate test, the antinociceptive effect was observed only in animals treated with 27 mg/kg of Gc-TSP, suggesting that the analgesic effect occurs through a central action mechanism at the highest dose. Gc-TSP (3, 9 or 27 mg/kg) caused only a slight reduction in neutrophil migration in the rat peritoneal cavity. However, lower doses of Gc-TSP (3 and 9 mg/kg) significantly inhibited paw oedema induced by carrageenan, especially at 3 hr after treatment. Reduction in oedema was confirmed by myeloperoxidase activity in the affected paw tissue. In addition, treatment (s.c.) of animals with different doses of Gc-TSP inhibited paw oedema induced by dextran within the first hour in all doses tested. After 14 consecutive days of intraperitoneal administration of Gc-TSP (9 mg/kg), we measured the wet weight of the liver, kidney, heart, spleen and thymus and performed biochemical, haematological and histopathological evaluations. No systemic damage was found. These results indicate that Gc-TSP possesses analgesic and anti-inflammatory effects and is a potentially important tool worthy of further study.

  17. Visual pigments, oil droplets, lens, and cornea characterization in the whooping crane (Grus americana)

    Science.gov (United States)

    Porter, Megan L.; Kingston, Alexandra C. N.; McCready, Robert; Cameron, Evan G.; Hofmann, Christopher M.; Suarez, Lauren; Olsen, Glenn H.; Cronin, Thomas W.; Robinson, Phyllis R.

    2014-01-01

    Vision has been investigated in many species of birds, but few studies have considered the visual systems of large birds and the particular implications of large eyes and long-life spans on visual system capabilities. To address these issues we investigated the visual system of the whooping crane, Grus americana (Gruiformes: Gruidae). G. americana (an endangered species) is one of only two North American crane species and represents a large, long-lived bird where ultraviolet sensitivity may be degraded by chromatic aberrations and entrance of ultraviolet light into the eye could be detrimental to retinal tissues. To investigate the whooping crane visual system we used microspectrophotometry to determine the absorbance spectra of retinal oil droplets and to investigate if the ocular media (i.e., the lens and cornea) absorbs UV light. In vitro expression and reconstitution was used to determine the absorbance spectra of rod and cone visual pigments. The rod visual pigments had wavelengths of peak absorbance (λmax) at 500 nm, while the cone visual pigments λmax values were determined to be 404 nm (SWS1), 450 nm (SWS2), 499 nm (RH2), and 561 nm (LWS), similar to other characterized bird visual pigment absorbance values. The oil droplet cutoff wavelength (λcut) values similarly fell within ranges recorded from other avian species: 576 nm (R-type), 522 nm (Y-type), 506 nm (P-type), and 448 nm (C-type). We confirm that G. americana has a violet-sensitive visual system, although based on the λmax of the SWS1 visual pigment (404 nm) may also have some ability for UV sensitivity.

  18. [The effects of ocular hypotensive drugs on the cornea: an in vivo analysis with confocal microscopy].

    Science.gov (United States)

    Fernández Jiménez-Ortiz, H; Toledano Fernández, N; Fernández Escamez, C S; Perucho Martinez, S; Crespo Carballés, M J

    2013-11-01

    To evaluate the effects of anti-glaucoma treatments containing benzalconium chloride (BAC) on the human cornea. A prospective single masked cohort study was conducted on the 50 eyes of 50 patients. The inclusion criteria were: recently diagnosed glaucoma or ocular hypertension with previous treatment, or ophthalmologist-prescribed anti-glaucoma therapy, and oral consent to participate in the study. The patients were not randomised, as the ophthalmologist decided the best therapy according to clinical criteria. The patients were divided in 2 cohorts: one exposed to BAC (23 patients), and not exposed (27 patients). The mean follow-up period was 22 weeks (range 18-30). The change in cell density before and after therapy was measured in: basal layer epithelium, basal layer of limbal epithelium and endothelium. The change in stromal reflectivity and the number of nerve branches in sub-basal nerve plexus was also measured. BAC exposure was blinded to the main researcher. A greater increase in basal layer epithelium cell density was observed in BAC exposed cohort (P<.05). No significant differences were detected in the endothelium, limbal cell density, stromal reflectivity, or sub-basal nerve plexus. Age, sex, IOP, active ingredient or BAC concentration did not affect the direction or magnitude of the ocular surface alterations found. Chronic anti-glaucoma therapy induces changes in the corneal epithelium. Preservative free drops showed less disruption of the ocular surface by confocal microscopy analysis. Further studies should be conducted to evaluate the clinical impact of these histological findings. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  19. Rebamipide increases the amount of mucin-like substances on the conjunctiva and cornea in the N-acetylcysteine-treated in vivo model.

    Science.gov (United States)

    Urashima, Hiroki; Okamoto, Takashi; Takeji, Yasuhiro; Shinohara, Hisashi; Fujisawa, Shigeki

    2004-08-01

    Rebamipide increases the amount of mucin-like substances in the stomach. We aimed to determine the effects of rebamipide on the amount of mucin-like substances in the conjunctiva and cornea of N-acetylcysteine-treated eyes. Furthermore, we attempted to evaluate the effects of rebamipide on the wound healing of N-acetylcysteine-treated eyes. The model was created by instilling 10% N-acetylcysteine solutions into rabbit eyes. Rebamipide was then applied on the day following the completion of N-acetylcysteine treatment. The amount of mucin-like substances on the conjunctiva and cornea was measured using the Alcian-blue binding method. The degree of damage was evaluated using scores based on the areas and densities of the cornea and conjunctival after staining using a rose Bengal solution under blind conditions. Rebamipide increased the level of mucin-like substances on the conjunctiva of N-acetylcysteine-treated eyes when instilled at concentrations of 0.3% or higher, and 1% rebamipide increased the amount of mucin-like substances covering the cornea. Moreover, 1% rebamipide improved the rose Bengal scores of the cornea and conjunctiva in N-acetylcysteine-treated eyes. Rebamipide increased mucin-like substances on the cornea and conjunctiva of N-acetylcysteine-treated eyes. In accordance with the mucin-increasing effects, rebamipide improved the rose Bengal scores for the cornea and conjunctiva of N-acetylcysteine-treated eyes. However, the relevance of these findings to dry eyes is unclear because it is not known whether the change in mucus expression in the N-acetylcysteine model is similar to what occurs in aqueous tear deficiency. Consequently, it may be worth trying on an animal model of keratoconjunctivitis sicca.

  20. Localization of angiotensin converting enzyme in rabbit cornea and its role in controlling corneal angiogenesis in vivo.

    Science.gov (United States)

    Sharma, Ajay; Bettis, Daniel I; Cowden, John W; Mohan, Rajiv R

    2010-04-23

    The renin angiotensin system (RAS) has been shown to modulate vascular endothelial growth factor and angiogenesis. In this study we investigated (i) the existence of the RAS components angiotensin converting enzyme (ACE) and angiotensin II receptors (AT(1) and AT(2)) in the rabbit cornea using in vitro and ex vivo models and (ii) the effect of enalapril, an ACE inhibitor, to inhibit angiogenesis in rabbit cornea in vivo. New Zealand White rabbits were used. Cultured corneal fibroblasts and corneal epithelial cells were used for RNA isolation and cDNA preparation using standard molecular biology techniques. PCR was performed to detect the presence of ACE, AT(1), and AT(2) gene expression. A corneal micropocket assay to implant a vascular endothelial growth factor (VEGF) pellet in the rabbit cornea was used to induce corneal angiogenesis. Rabbits of the control group received sterile water, and the treated group received 3 mg/kg enalapril intramuscularly once daily for 14 days starting from day 1 of pellet implantation. The clinical eye examination was performed by slit-lamp biomicroscopy. We monitored the level of corneal angiogenesis in live animals by stereomicroscopy at days 4, 9, and 14 after VEGF pellet implantation. Collagen type IV and lectin immunohistochemistry and fluorescent microscopy were used to measure corneal angiogenesis in tissue sections of control and enalapril-treated corneas of the rabbits. Image J software was used to quantify corneal angiogenesis in the rabbit eye in situ. Our data demonstrated the presence of ACE, AT(1), and AT(2) expression in corneal fibroblasts. Cells of corneal epithelium expressed AT(1) and AT(2) but did not show ACE expression. Slit-lamp examination did not show any significant difference between the degree of edema or cellular infiltration between the corneas of control and enalapril-treated rabbits. VEGF pellet implantation caused corneal angiogenesis in the eyes of vehicle-treated control rabbits, and the mean area

  1. Brittle cornea syndrome ZNF469 mutation carrier phenotype and segregation analysis of rare ZNF469 variants in familial keratoconus.

    Science.gov (United States)

    Davidson, Alice E; Borasio, Edmondo; Liskova, Petra; Khan, Arif O; Hassan, Hala; Cheetham, Michael E; Plagnol, Vincent; Alkuraya, Fowzan S; Tuft, Stephen J; Hardcastle, Alison J

    2015-01-06

    Brittle cornea syndrome 1 (BCS1) is a rare recessive condition characterized by extreme thinning of the cornea and sclera, caused by mutations in ZNF469. Keratoconus is a relatively common disease characterized by progressive thinning and ectasia of the cornea. The etiology of keratoconus is complex and not yet understood, but rare ZNF469 variants have recently been associated with disease. We investigated the phenotype of BCS1 carriers with known pathogenic ZNF469 mutations, and recruited families in which aggregation of keratoconus was observed to establish if rare variants in ZNF469 segregated with disease. Patients and family members were recruited and underwent comprehensive anterior segment examination, including corneal topography. Blood samples were donated and genomic DNA was extracted. The coding sequence and splice sites of ZNF469 were PCR amplified and Sanger sequenced. Four carriers of three BCS1-associated ZNF469 loss-of-function mutations (p.[Glu1392Ter], p.[Gln1930Argfs*6], p.[Gln1930fs*133]) were examined and none had keratoconus. One carrier had partially penetrant features of BCS1, including joint hypermobility. ZNF469 sequencing in 11 keratoconus families identified 9 rare (minor allele frequency [MAF] ≤ 0.025) variants predicted to be potentially damaging. However, in each instance the rare variant(s) identified, including two previously reported as potentially keratoconus-associated, did not segregate with the disease. The presence of heterozygous loss-of-function alleles in the ZNF469 gene did not cause keratoconus in the individuals examined. None of the rare nonsynonymous ZNF469 variants identified in the familial cohort conferred a high risk of keratoconus; therefore, genetic variants contributing to disease pathogenesis in these 11 families remain to be identified. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

  2. Artificial cornea: surface modification of silicone rubber membrane by graft polymerization of pHEMA via glow discharge.

    Science.gov (United States)

    Lee, S D; Hsiue, G H; Kao, C Y; Chang, P C

    1996-03-01

    A method for producing various surfaces of silicone rubber membrane (SR) was developed in this study by grafting various amounts of poly(2-hydroxy ethyl methacrylate) (pHEMA) onto SR by plasma-induced grafted polymerization (PIP) as a homobifunctional membrane. The elemental composition and different carbon bindings on the surface of SR were examined by electron spectroscopy for chemical analysis with the amount of O1s/C1s being approximately 0.7 at 1 min, 60 W, 200 mTorr of Ar-plasma treatment. The peroxide group introduced on SR was measured via 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the amount of 6.85 x 10(-8) mol cm-2 reached optimum value at 1 min of Ar-plasma treatment. After Ar-plasma treated SR, the peroxide group (33D peak) was introduced on the surface of SR by negative spectra of secondary ion mass spectroscopy analysis, whereas ester groups (72D peak) were observed for pHEMA-grafted SR. For the in vitro test, the influence of various surfaces of SR on attachment and growth of rabbit corneal epithelial cells (CEC) was studied by cell culture assay. These results indicated that 56-150 micrograms cm-2 of pHEMA grafted onto SR were suitable values for attachment and growth of CEC. On the contrary, the large grafted amounts (500-1650 micrograms cm-2) of pHEMA on SR were insufficient for attachment and growth of CEC. For the in vivo test, the migration of CEC from host cornea to implant was investigated by slit lamp microscopy. The experimental results indicated that SRs grafted with pHEMA were completely covered with CEC 3 weeks after implantation of the membranes into the host cornea. These results provide a valuable reference for developing an artificial cornea.

  3. Noninvasive measurement of wave speed of porcine cornea in ex vivo porcine eyes for various intraocular pressures.

    Science.gov (United States)

    Zhou, Boran; Sit, Arthur J; Zhang, Xiaoming

    2017-11-01

    The objective of this study was to extend an ultrasound surface wave elastography (USWE) technique for noninvasive measurement of ocular tissue elastic properties. In particular, we aim to establish the relationship between the wave speed of cornea and the intraocular pressure (IOP). Normal ranges of IOP are between 12 and 22mmHg. Ex vivo porcine eye balls were used in this research. The porcine eye ball was supported by the gelatin phantom in a testing container. Some water was pour into the container for the ultrasound measurement. A local harmonic vibration was generated on the side of the eye ball. An ultrasound probe was used to measure the wave propagation in the cornea noninvasively. A 25 gauge butterfly needle was inserted into the vitreous humor of the eye ball under the ultrasound imaging guidance. The needle was connected to a syringe. The IOP was obtained by the water height difference between the water level in the syringe and the water level in the testing container. The IOP was adjusted between 5mmHg and 30mmHg with a 5mmHg interval. The wave speed was measured at each IOP for three frequencies of 100, 150 and 200Hz. Finite element method (FEM) was used to simulate the wave propagation in the corneal according to our experimental setup. A linear viscoelastic FEM model was used to compare the experimental data. Both the experiments and the FEM analyses showed that the wave speed of cornea increased with IOP. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. T-style keratoprosthesis based on surface-modified poly (2-hydroxyethyl methacrylate) hydrogel for cornea repairs

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Jun [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Sun, Jianguo [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); State Key Laboratory of Molecular Engineering of Polymers, Fudan University (China); Hong, Jiaxu [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Wang, Wentao [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Wei, Anji [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Le, Qihua [Research Center, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China); Xu, Jianjiang, E-mail: jianjiang-xu@163.com [Department of Ophthalmology, Eye & ENT Hospital, Shanghai Medical College, Fudan University (China); Key Laboratory of Myopia, Ministry of Health, Fudan University (China); Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University (China)

    2015-05-01

    Corneal disease is a common cause of blindness, and keratoplasty is considered as an effective treatment method. However, there is a severe shortage of donor corneas worldwide. This paper presents a novel T-style design of a keratoprosthesis and its preparation methods, in which a mechanically and structurally effective artificial cornea is made based on a poly(2-hydroxyethyl methacrylate) hydrogel. The porous skirt was modified with hyaluronic acid and cationized gelatin, and the bottom of the optical column was coated with poly(ethylene glycol). The physical properties of the T-style Kpro were analyzed using ultraviolet and visible spectrophotometry and electron scanning microscopy. The surface chemical properties were characterized using Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The surface modification in the spongy skirt promoted cell adhesion and produced a firm bond between the corneal tissue and the implant device, while the surface modification in the optic column resisted cell adhesion and prevented retroprosthetic membrane formation. Through improved surgical techniques, the novel T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with the host environment. In vivo implantation experiments showed that the T-style keratoprosthesis is a promising cornea alternative for patients with severe limbal stem cell deficiency and corneal opacity. - Highlights: • T-style keratoprosthesis was designed and prepared based on a PHEMA hydrogel. • Selective surface modifications effectively regulated cells' selective adhesion. • T-style keratoprosthesis provides enough mechanical stability to facilitate long-term biointegration with host tissues.

  5. Innervation of TRPV1-, PGP-, and CGRP-immunoreactive nerve fibers in the subepithelial layer of a whole mount preparation of the rat cornea.

    Science.gov (United States)

    Hiura, Akio; Nakagawa, Hiroshi

    2012-01-01

    The pattern of innervation of capsaicin receptor, TRPV1-(transient receptor protein vanilloid 1), PGP 9.5-(protein gene product, a marker of peripheral nerve fibers)-, and CGRP (calcitonin gene-related peptide)-immunoreactive (IR) nerve fibers was examined by immunohistological staining of whole mount preparations of the adult rat cornea. The outer corneoscleral limbus toward the central cornea in the subepithelial (stromal) layer was richly innervated by a meshwork of PGP- and CGRP-IR nerve fibers. Sparse innervation was observed in the central cornea, presumably owing to insufficient staining. Dense innervation of TRPV1-IR nerve fibers were demonstrated in addition to innervation of PGP- and CGRP-IR nerve fibers, running from the corneoscleral margin to the central cornea. Although the density of TRPV1-IR nerve fibers appeared to gradually diminish, immunostaining of TRPV1-IR nerve fibers was not as clear as that of PGP- and CGRP-IR nerve fibers. The TRPV1-IR nerve fibers appeared to be thinner than the PGP- and CGRP-IR nerve fibers. The TRPV1-IR leash fibers were observed in the basal epithelial layer, presumably ensuring effective corneal reflex, response to noxious stimuli, and repair of cornea injury.

  6. Lymphatic vessels growing apart from blood vessels in transplanted corneas after the blockade of vascular endothelial growth factor C

    Institute of Scientific and Technical Information of China (English)

    Ye Hui; Yan Hao; Zhong Lei; Wang Tao; Deng Juan; Ling Shi-qi

    2016-01-01

    BACKGROUND:Corneal lymphangiogenesis is beneficial to the transport of corneal antigenic materials, and accelerates the process of antigen presentation, thereby playing an important role in corneal immunity. However, due to the paral el outgrowth of corneal blood and lymphatic vessels in transplanted corneas, it is often difficult to accurately evaluate the role of corneal lymphatic vessels in allograft rejection. OBJECTIVE:To explore the development of corneal lymphangiogenesis and angiogenesis in transplanted rat corneas after the blockade of vascular endothelial growth factor C (VEGF-C). METHODS:130 rats used to establish corneal al ogenic transplantation models were equally randomized into two groups:the anti-VEGF-C group and the control group. VEGF-C was blocked in the anti-VEGF-C group by intraperitoneal injection of neutralizing monoclonal anti-VEGF-C antibody every other day for 2 consecutive weeks. Meanwhile, rats in control groups received intraperitoneal injections of saline. Corneal angiogenesis and lymphangiogenesis were characterized using whole mount immunofluorescence, and the immune rejection of the grafts was evaluated by scoring the rejection index (RI). In addition, the expression of VEGF-C was examined by real-time PCR. The relationship of corneal lymphangiogenesis and angiogenesis to RI in transplanted corneas was also characterized. RESULTS AND CONCLUSION:VEGF-C expression was markedly downregulated after VEGF-C blockade. Corneal lymphangiogenesis developed in parallel with corneal angiogenesis in the control group. While there was a mild reduction in blood vessel area (BVA) and a significant decrease in lymphatic vessel area (LVA) in the anti-VEGF-C group (P0.05). the graft survival time in the anti-VEGF-C group was significantly increased compared with that in the control group (P<0.05). Our results show that the outgrowth of lymphatic vessels is separated from that of blood vessels in transplanted corneas by blocking VEGF-C. The blockade

  7. Change in over-refraction after scleral lens settling on average corneas.

    Science.gov (United States)

    Bray, Chelsea; Britton, Stephanie; Yeung, Debby; Haines, Lacey; Sorbara, Luigina

    2017-07-01

    The purpose of this study was to determine the change in over-refraction, if any, after a scleral lens settled on the eye for 6-8 h. Sixteen patients of varying refractive errors and normal corneal curvatures (measured with Pentacam(™) Oculus) were fitted with trial Mini-Scleral Design (MSD) scleral lenses (15.8 mm diameter) in one eye. The sagittal depths of the scleral lenses were selected by adding 350 μm to the corneal sagittal heights measured at a chord length of 15 mm with the Visante(™) optical coherence tomographer (OCT) anterior segment scans and picking the closest available trial lens in the set. Initial measurements were taken 30 min after lens insertion and included an auto-refraction, subjective refraction, and best sphere refraction over the contact lens. Visual acuities and Visante(™) OCT anterior segment scans were also taken. These measurements were repeated after 6-8 h of lens wear. Over the trial wearing period, the average change in the spherical component of the over-refraction was +0.06 D (S.D. 0.17) (p = 0.16). The average change in cylinder was +0.04 D (S.D. 0.19) (p = 0.33). The average absolute change in axis was 1.06° (S.D. 12.11) (p = 0.74). The average change in best sphere was +0.13 ± 0.30 D (p = 0.12). There was no significant change in visual acuity with the best sphere over-refraction over the 6-8 h wearing period. There was a significant change in central corneal clearance over the wearing period of 83 μm (S.D. 22) (p refraction (sphere, cylinder, and axis) or best sphere or visual acuity. This study has confirmed that there is no link between reduction in central corneal clearance and change in over-refraction for average corneas. © 2017 The Authors Ophthalmic & Physiological Optics © 2017 The College of Optometrists.

  8. Phage display against corneal epithelial cells produced bioactive peptides that inhibit Aspergillus adhesion to the corneas.

    Directory of Open Access Journals (Sweden)

    Ge Zhao

    Full Text Available Dissection of host-pathogen interactions is important for both understanding the pathogenesis of infectious diseases and developing therapeutics for the infectious diseases like various infectious keratitis. To enhance the knowledge about pathogenesis infectious keratitis, a random 12-mer peptide phage display library was screened against cultured human corneal epithelial cells (HCEC. Fourteen sequences were obtained and BLASTp analysis showed that most of their homologue counterparts in GenBank were for defined or putative proteins in various pathogens. Based on known or predicted functions of the homologue proteins, ten synthetic peptides (Pc-A to Pc-J were measured for their affinity to bind cells and their potential efficacy to interfere with pathogen adhesion to the cells. Besides binding to HCEC, most of them also bound to human corneal stromal cells and umbilical endothelial cells to different extents. When added to HCEC culture, the peptides induced expression of MyD88 and IL-17 in HCEC, and the stimulated cell culture medium showed fungicidal potency to various extents. While peptides Pc-C and Pc-E inhibited Aspergillus fumigatus (A.f adhesion to HCEC in a dose-dependent manner, the similar inhibition ability of peptides Pc-A and Pc-B required presence of their homologue ligand Alb1p on A.f. When utilized in an eyeball organ culture model and an in vivo A.f keratitis model established in mouse, Pc-C and Pc-E inhibited fungal adhesion to corneas, hence decreased corneal disruption caused by inflammatory infiltration. Affinity pull-down of HCEC membrane proteins with peptide Pc-C revealed several molecules as potential receptors for this peptide. In conclusion, besides proving that phage display-selected peptides could be utilized to interfere with adhesion of pathogens to host cells, hence could be exploited for managing infectious diseases including infectious keratitis, we also proposed that the phage display technique and the

  9. The effect of hypergravity on the lens, cornea and tail regeneration in Urodela

    Science.gov (United States)

    Grigoryan, E. N.; Dvorochkin, N.; Poplinskaya, V. A.; Yousuf, R.; Radugina, E. A.; Almeida, E. A.

    2017-09-01

    In previous experiments onboard Russian Bion/Foton satellites it was found that exposure to microgravity causes changes in eye lens regeneration of Urodela. The changes included higher rate of regeneration, increased cell proliferation in lens anlage, and synchronization of lens restoration. Similar changes were observed regarding tail regeneration. Recently, investigations were performed to find out whether exposure to hypergravity could also alter lens, cornea and tail regeneration in the newt P. waltl. Nine days prior to exposure the left lens was surgically removed through corneal incision and distal 1/3 of the tail was amputated, thus initiating regeneration. The experimental animals were allowed to recover for 9 days at 1 g and then exposed to 2 g for 12 days in an 8 ft diameter centrifuge at NASA Ames Research Center. The experimental animals were divided into 1 g controls, 2 g centrifugation animals, basal controls, and aquarium controls. Lens and corneal regeneration appeared to be inhibited in 2 g group compared to 1 g animals. In all 1 g controls, lens regeneration reached stages VII-IX in a synchronous fashion and corneal regeneration was nearly complete. In the 2 g newts, neural retinal detachment from the pigmented epithelium was seen in most operated eyes. It was also observed in the non-operated (right) eyes of the animals exposed to 2 g. The level of retinal detachment varied and could have been caused by hypergravity-induced high intraocular pressure. Regeneration (when it could be assessed) proceeded asynchronously, reaching stages from II to IX. Corneal restoration was also noticeably delayed and corneal morphology changed. Cell proliferation was measured using BrdU; the results were not comparable to the 1 g data because of retinal detachment. Previous investigations demonstrated that lens regeneration was controlled by the neural retina; therefore, lower regeneration rate at 2 g was, at least in part, associated with retinal detachment. FGF2

  10. Analysis of two precipitation methods on the yield, structural features and activity of sulfated polysaccharides from Gracilaria cornea (Rhodophyta

    Directory of Open Access Journals (Sweden)

    Ricardo Basto Souza

    2015-03-01

    Full Text Available The global demand for natural products from seaweeds has increased worldwide; however, no description of the use of isoamly alcohol (IAA for obtaining of sulfated polysaccharides (SPs has been reported. We investigated the efficiency of two precipitation methods (M in obtaining SPs from the red seaweed Gracilaria cornea. SPs enzymatically isolated were concentrated with cetylpyridinium chloride (M I or IAA (M II and extracts were examined with regard to their yield, structural features and in vitro effects on the activated partial thromboplastin time (APTT using normal human plasma and standard heparin (193 IU mg-1. Yield difference reached 12.99%. Quantitative determination of sulfate was similar between the two methods (̴ 26%, but extracts revealed different pattern on charge density by agarose gel electrophoresis. Whereas both extracts revealed as agarocolloids, alternative M II was also efficient for lipids, proteins and nucleic acids according to the infrared analysis. Extracts had virtually no effect on APPT (1.95 and 2 IU mg-1 for M I and M II, respectively. The results revealed IAA as an alternative solvent for obtaining SPs from the red seaweed G. cornea, depending on the industry’ usage criterion.

  11. The short-term effects of PMMA contact lens wear on keratometric behaviour: results for a single keratoconic cornea*

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    E. Chetty

    2010-12-01

    Full Text Available Keratometric behaviour is a multifaceted issue that many researchers have investigated for years. Many internal and external influences can have an effect on the cornea’s keratometric behaviour. This investigation forms a small part of a larger study that aims at determining the effects that rigid contact lenses might have on keratometric behaviour. This pilot study examined the keratometric behaviour of a single, mildly keratoconic cornea that was fitted with a polymethyl methacrylate (PMMA contact lens. Sixty successive auto-keratometric measurements were taken immediately before and immediately after three hours of contact lens wear. The data obtained was transformed to dioptric power matrices and were analysed using multivariate statistical methods. This study showed that, at least in one keratoconic cornea, there appeared to be a statistically significant change in corneal curvature under the influence of a PMMA contact lens. The contact lens had also appeared to decrease variation in corneal curvature. There was no control study done on this eye therefore the effects of diurnal variation, if any, could not be established. (S Afr Optom 2010 69(2 69-76

  12. Common genetic variants near the Brittle Cornea Syndrome locus ZNF469 influence the blinding disease risk factor central corneal thickness.

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    Yi Lu

    2010-05-01

    Full Text Available Central corneal thickness (CCT, one of the most highly heritable human traits (h(2 typically>0.9, is important for the diagnosis of glaucoma and a potential risk factor for glaucoma susceptibility. We conducted genome-wide association studies in five cohorts from Australia and the United Kingdom (total N = 5058. Three cohorts were based on individually genotyped twin collections, with the remaining two cohorts genotyped on pooled samples from singletons with extreme trait values. The pooled sample findings were validated by individual genotyping the pooled samples together with additional samples also within extreme quantiles. We describe methods for efficient combined analysis of the results from these different study designs. We have identified and replicated quantitative trait loci on chromosomes 13 and 16 for association with CCT. The locus on chromosome 13 (nearest gene FOXO1 had an overall meta-analysis p-value for all the individually genotyped samples of 4.6x10(-10. The locus on chromosome 16 was associated with CCT with p = 8.95x10(-11. The nearest gene to the associated chromosome 16 SNPs was ZNF469, a locus recently implicated in Brittle Cornea Syndrome (BCS, a very rare disorder characterized by abnormal thin corneas. Our findings suggest that in addition to rare variants in ZNF469 underlying CCT variation in BCS patients, more common variants near this gene may contribute to CCT variation in the general population.

  13. Quantitative & qualitative analysis of endothelial cells of donor cornea before & after penetrating keratoplasty in different pathological conditions

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    Aruna K.R. Gupta

    2016-01-01

    Full Text Available Background & objectives: Endothelial cells of the donor cornea are known to be affected quantitatively and qualitatively in different pathological conditions after penetrating keratoplasty (PK and this has direct effect on the clarity of vision obtained after PK. This study was undertaken to analyze the qualitative and quantitative changes in donor endothelial cells before and after PK in different pathological conditions. Methods: A prospective investigational analysis of 100 consecutive donor corneas used for penetrating keratoplasty between June 2006 and June 2008, was conducted. The patients were evaluated on the first day, at the end of first week, first month, third and six months and one year. Results: A decrease was observed in endothelial cell count in all pathological conditions. After one year of follow up the loss was 33.1 per cent in corneal opacity, 45.9 per cent in acute infective keratitis (AIK, 58.5 per cent in regrafts, 28.5 per cent in pseudophakic bullous keratopathy (PBK, 37 per cent in descemetocele, 27 per cent in keratoconus and 35.5 per cent in aphakic bullous keratopathy (ABK cases. Interpretation & conclusions: The endothelial cell loss was highest in regraft cases which was significant (P<0.05, while the least endothelial cell loss was seen in keratoconus cases. The cell loss was associated with increase in coefficient of variation (CV, i.e. polymegathism and pleomorphism. Inspite of this polymegathism and pleomorphism, the clarity of the graft was maintained.

  14. Visual outcomes after deep anterior lamellar keratoplasty using donor corneas without removal of Descemet membrane and endothelium

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    Tatiana Moura Bastos Prazeres

    Full Text Available ABSTRACT Purpose: The optical quality of the interface after deep anterior lamellar keratoplasty (DALK using the big-bubble technique has been shown to be excellent, leading to results comparable to penetrating keratoplasty. However, there is little in the literature with respect to the controversy surrounding the preparation of the donor cornea. The purpose of this study was to evaluate visual acuity (VA in patients with keratoconus who underwent DALK without removal of the donor graft endothelium. Methods: The records of 90 patients who underwent DALK without the removal of the Descemet membrane (DM and endothelium were retrospectively reviewed. Data collected included uncorrected VA (UCVA and spectacle-corrected VA (SCVA at 7, 30, 180 days, and 1 year postoperatively. Contact lens-corrected visual acuity (CLVA was evaluated after 1 year of the procedure. Results: UCVA was significantly better than preoperative values at 7 days (p<0.001, 30 days (p<0.001, 180 days (p<0.001, and 1 year (p<0.001 after surgery. The 1-year postoperative mean SCVA and CLVA also improved when compared with preoperative SCVA (p<0.001 for both. Conclusions: DALK utilizing donor corneas with attached Descemet membrane and endothelium results in satisfactory VA in patients with keratoconus.

  15. Common genetic variants near the Brittle Cornea Syndrome locus ZNF469 influence the blinding disease risk factor central corneal thickness.

    Directory of Open Access Journals (Sweden)

    Yi Lu

    2010-05-01

    Full Text Available Central corneal thickness (CCT, one of the most highly heritable human traits (h(2 typically>0.9, is important for the diagnosis of glaucoma and a potential risk factor for glaucoma susceptibility. We conducted genome-wide association studies in five cohorts from Australia and the United Kingdom (total N = 5058. Three cohorts were based on individually genotyped twin collections, with the remaining two cohorts genotyped on pooled samples from singletons with extreme trait values. The pooled sample findings were validated by individual genotyping the pooled samples together with additional samples also within extreme quantiles. We describe methods for efficient combined analysis of the results from these different study designs. We have identified and replicated quantitative trait loci on chromosomes 13 and 16 for association with CCT. The locus on chromosome 13 (nearest gene FOXO1 had an overall meta-analysis p-value for all the individually genotyped samples of 4.6x10(-10. The locus on chromosome 16 was associated with CCT with p = 8.95x10(-11. The nearest gene to the associated chromosome 16 SNPs was ZNF469, a locus recently implicated in Brittle Cornea Syndrome (BCS, a very rare disorder characterized by abnormal thin corneas. Our findings suggest that in addition to rare variants in ZNF469 underlying CCT variation in BCS patients, more common variants near this gene may contribute to CCT variation in the general population.

  16. Photography of shock waves during excimer laser ablation of the cornea. Effect of helium gas on propagation velocity.

    Science.gov (United States)

    Krueger, R R; Krasinski, J S; Radzewicz, C; Stonecipher, K G; Rowsey, J J

    1993-07-01

    Shadow photography of shock waves excited by means of a xenon chloride excimer laser was performed to determine the shock wave propagation velocity in air, nitrogen and helium. Energy densities between 500 and 2,000 mJ/cm2 were used to ablate a rotating rubber cylindrical target and porcine corneas. In ablating the rubber cylinder, a shock wave velocity of 3.3 km/s was generated in air and nitrogen at 40 ns; this decreased to 1.4 km/s at 320 ns. When helium was blown on the target, the velocity increased by a factor of approximately two, to 5.9 km/s at 40 ns and 2.7 km/s at 320 ns. We suggest that blowing helium on the surface of the cornea during excimer laser ablation may speed the dissipation of high-energy acoustic waves and gaseous particles, and thus reduce the exposure and transfer of heat energy to the surrounding tissue.

  17. Differentiating untreated and cross-linked porcine corneas of the same measured stiffness with optical coherence elastography

    Science.gov (United States)

    Li, Jiasong; Han, Zhaolong; Singh, Manmohan; Twa, Michael D.; Larin, Kirill V.

    2014-11-01

    Structurally degenerative diseases, such as keratoconus, can significantly alter the stiffness of the cornea, directly affecting the quality of vision. Ultraviolet-induced collagen cross-linking (CXL) effectively increases corneal stiffness and is applied clinically to treat keratoconus. However, measured corneal stiffness is also influenced by intraocular pressure (IOP). Therefore, experimentally measured changes in corneal stiffness may be attributable to the effects of CXL, changes in IOP, or both. We present a noninvasive measurement method using phase-stabilized swept-source optical coherence elastography to distinguish between CXL and IOP effects on measured corneal stiffness. This method compared the displacement amplitude attenuation of a focused air-pulse-induced elastic wave. The damping speed of the displacement amplitudes at each measurement position along the wave propagation were compared for different materials. This method was initially tested on gelatin and agar phantoms of the same stiffness for validation. Consequently, untreated and CXL-treated porcine corneas of the same measured stiffness, but at different IOPs, were also evaluated. The results suggest that this noninvasive method may have the potential to detect the early stages of ocular diseases such as keratoconus or may be applied during CLX procedures by factoring in the effects of IOP on the measured corneal stiffness.

  18. In vitro evaluation of the permeation enhancing effect of polycarbophil-cysteine conjugates on the cornea of rabbits.

    Science.gov (United States)

    Hornof, Margit D; Bernkop-Schnürch, Andreas

    2002-12-01

    It was the aim of this study to investigate the permeation enhancing effect of thiolated polycarbophil on the cornea of rabbits in vitro. The proposed reaction mechanism involves the opening of the tight junctions in the corneal epithelium. The modification of polycarbophil was achieved via covalent attachment of L-cysteine mediated by a carbodiimide. Transcorneal permeation studies were performed in Ussing-type diffusion chambers. As model compounds, sodium fluorescein, as a marker for paracellular transport, and dexamethasone phosphate were used. To evaluate potential corneal damage the corneal hydration level of each cornea was determined. Polycarbophil-cysteine was found to increase the permeation of sodium fluorescein 2.2-fold and that of dexamethasone phosphate 2.4-fold in comparison to the unmodified polymer. The concentration of dexamethasone in the acceptor medium was 1.5-fold increased. As evidenced by the corneal hydration level, polycarbophil-cysteine did not damage the corneal tissues. Therefore, polycarbophil-cysteine conjugates seem to be promising excipients for ocular drug delivery systems where they might be used as safe permeation enhancers.

  19. Differential Effects of Dexamethasone and Doxycycline on Inflammation and MMP Production in Murine Alkali-Burned Corneas Associated with Dry Eye.

    Science.gov (United States)

    Bian, Fang; Pelegrino, Flavia S A; Henriksson, Johanna Tukler; Pflugfelder, Stephen C; Volpe, Eugene A; Li, De-Quan; de Paiva, Cintia S

    2016-04-01

    Alkali burns to the cornea are among the most devastating injuries to the eye. The purpose of this study was to evaluate the effects of dexamethasone (Dex) or doxycycline (Doxy) on protease activity and corneal complications in a combined model (CM) of alkali burn and dry eye. C57BL/6 mice were subjected to the CM for 2 or 5 days (D). Mice were topically treated either with Dex (0.1%), Dox (0.025%) or vehicle QID and observed daily for appearance of corneal perforation. Quantitative real time PCR was performed to measure expression of inflammation cytokines and matrix metalloproteinases (MMPs) in whole cornea lysates. No perforations were observed in the Dex-treated corneas. All wounds in Doxy-treated corneas were closed 2D post-injury, and they had significantly lower corneal opacity scores at days 4 and 5 post-injury compared to BSS treatment. Dex-treated corneas had the lowest corneal opacity scores. Dex treatment significantly decreased expression of IL-1β, IL-6, MMPs -1, -9, -13, and TIMP-1 after 2 days but increased levels of MMP-8, while Doxy treatment significantly decreased IL-1β, IL-6, MMP-8, and -9, compared to vehicle. Decreased MMP-1, -9 and -13 immunoreactivity and gelatinolytic activity were seen in corneas treated with Doxy and Dex compared to vehicle. Increased neutrophil infiltration and myeloperoxidase activity was noted in the vehicle group compared to Dex 2 days post-injury. These findings demonstrate that early initiation of anti-inflammatory therapy is very efficacious in preserving corneal clarity and facilitating wound healing, while modulating MMP production and suppressing neutrophil infiltration. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Research progress in scaffolds of tissue engineered cornea%组织工程化角膜支架的研究进展

    Institute of Scientific and Technical Information of China (English)

    张凯

    2012-01-01

    近20年来,应用组织工程技术构建角膜组织——组织工程化角膜的构建取得了较大的进展.然而,能够广泛应用于临床的组织工程化角膜的构建仍不够完善.组织工程化角膜支架是构建组织工程化角膜的重要组成部分之一.探寻生物相容性好、可降解并具有足够生物力学强度的支架材料是组织工程化角膜研究领域亟待解决的课题.就组织工程化角膜支架的发展历程进行概括总结,评价不同支架材料的优缺点,拓展理想支架材料的研发视野,为可广泛用于临床的组织工程化角膜的研制提供信息.%Great progress has been made in tissue engineering cornea construction (i.c.constructing human corneal equivalence by using tissue engineering technique) during the past 20 years.However,a kind of tissue engineering cornea which can be applied to corneal transplantation as human cornea equivalent is yet to be availablc.Scaffold is an indispensable part of tissue engineering cornea.Searching for some kinds of scaffolds with good biocompability,some extent of biodegradation and euough biomechanics property are the issue needing to be resolved immediately in the tissue engineering cornea filed.This article reviewed the development of tissue engineering cornea scaffolds,represented the merits and defects of different scaffolds in order to optimize the project of choosing scaffolds and furthermore lay the foundation for constructing a kind of tissue engineering cornea which may be applied to corneal transplantation as human cornea equivalent in the future.

  1. Two-photon spectral fluorescence lifetime and second-harmonic generation imaging of the porcine cornea with a 12-femtosecond laser microscope

    Science.gov (United States)

    Batista, Ana; Breunig, Hans Georg; Uchugonova, Aisada; Morgado, António Miguel; König, Karsten

    2016-03-01

    Five dimensional microscopy with a 12-fs laser scanning microscope based on spectrally resolved two-photon autofluorescence lifetime and second-harmonic generation (SHG) imaging was used to characterize all layers of the porcine cornea. This setup allowed the simultaneous excitation of both metabolic cofactors, NAD(P)H and flavins, and their discrimination based on their spectral emission properties and fluorescence decay characteristics. Furthermore, the architecture of the stromal collagen fibrils was assessed by SHG imaging in both forward and backward directions. Information on the metabolic state and the tissue architecture of the porcine cornea were obtained with subcellular resolution, and high temporal and spectral resolutions.

  2. Microbiological profile of donor corneas stored for tectonic transplantation purposes in rabbits Microbiologia de amostras de bancos de córneas destinadas a transplantes, em coelhos

    Directory of Open Access Journals (Sweden)

    K.K. Kobashigawa

    2013-02-01

    Full Text Available This study aimed to evaluate the microbiota of donor rabbit corneas stored for tectonic transplantation purposes. Swabs from both corneas of 20 rabbits were carefully collected and submitted to microorganism isolation and identification. After this first swab collection, rabbits were euthanized for reasons other than this project and the eyes were enucleated. The corneas were collected and stored to compose the cornea tissue bank. Corneas were stored in a 0.3% tobramycin solution at -20ºC. After 30 days, the corneas were thawed at room temperature and removed from the antibiotic. New swabs were obtained from the corneas and submitted to microorganism isolation and identification. Gram positive organisms were predominant in the rabbit corneal flora before storage and the Staphylococcus sp. was the most common microorganism isolated from those samples. No growth was observed on the samples collected after storage. The methods used for collection and storage of the corneas were efficient to constitute a sterile donor corneal tissue bank.Analisaram-se córneas armazenadas para transplantes tectônicos usando-se suabes coletados de 20 coelhos, visando ao isolamento e à identificação de microrganismos. Após a coleta das amostras, os coelhos foram submetidos à eutanásia, por razões alheias ao estudo, e enucleados. As córneas foram coletadas e armazenadas a fim de se constituir o banco de córneas. O armazenamento deu-se em solução de tobramicina 0,3% a -20ºC, por 30 dias. Após esse período, as córneas foram descongeladas à temperatura ambiente e removidas da solução de antibiótico. Novos suabes foram coletados e submetidos ao isolamento e à identificação dos microrganismos. A flora corneal mostrou-se predominantemente composta por bactérias Gram positivas, sendo o Staphylococcus sp. o mais identificado. Não se verificou crescimento de colônias bacterianas ou fúngicas nas amostras após o armazenamento. Considerando-se a

  3. 人工角膜及其相关材料%Artificial cornea and related materials

    Institute of Scientific and Technical Information of China (English)

    严拓; 敖宁建; 覃百花; 邓华

    2008-01-01

    学术背景:对于同种异体角膜移植失败的患者,人工角膜移植便成了复明的惟一希望.人工角膜的研究虽然已经跨越2个世纪,但由于各种因素限制,角膜植入术仍然只能在少数中心开展.近年来,由于相关学科的飞速发展,人工角膜也进入了快速发展时期.目的:从材料选择、片型设计、材料改性以及临床试验等角度进行叙述,比较不同结构人工角膜各自特点,并指出目前人工角膜所存在的主要问题,对理想的人工角膜提出了新的见解.检索策略:作者应用计算机检索中国全文期刊数据库(CNKI),Springer,EI,Blackwell数据库1993-01/2007-12与人工角膜相关文献.所用中文检索词有"人工角膜、角膜穿透术";英文榆索词包括"artificial cornea,penetrating keratoplasty".纳入标准:文章内容与人工角膜材料、片型设计、临床研究有关.排除标准:较为陈旧,重复性研究.文献评价:共检索到86篇相关文献,68篇文献符合上述要求,其中12篇为综述性文献,37篇为基础性研究文献,19篇为临床研究文献,从中选择30篇进行综述.资料综合:人工角膜材料包括光学镜柱材料(水凝胶、聚甲基丙烯酸甲酯、硅凝胶、玻璃)和支架材料(氟碳聚合物、羟基磷灰石、生物材料).材料改性包括材料化学改性、材料表面处理、材料表面修饰、材料表面等离子处理.不同的角膜片型设计中,较为成功的是AlphaCor和Osteo-Odonto,并获得了美国食品药品管理局批准,进入临床阶段.结论:提高人工角膜与组织黏附度,减少并发症是长期研究的重点领域,而材料选择、材料改性、片型设计等是解决的关键.

  4. Establishment of a new in vitro test method for evaluation of eye irritancy using a reconstructed human corneal epithelial model, LabCyte CORNEA-MODEL.

    Science.gov (United States)

    Katoh, Masakazu; Hamajima, Fumiyasu; Ogasawara, Takahiro; Hata, Ken-ichiro

    2013-12-01

    Finding in vitro eye irritation testing alternatives to animal testing such as the Draize eye test, which uses rabbits, is essential from the standpoint of animal welfare. It has been developed a reconstructed human corneal epithelial model, the LabCyte CORNEA-MODEL, which has a representative corneal epithelium-like structure. Protocol optimization (pre-validation study) was examined in order to establish a new alternative method for eye irritancy evaluation with this model. From the results of the optimization experiments, the application periods for chemicals were set at 1min for liquid chemicals or 24h for solid chemicals, and the post-exposure incubation periods were set at 24h for liquids or zero for solids. If the viability was less than 50%, the chemical was judged to be an eye irritant. Sixty-one chemicals were applied in the optimized protocol using the LabCyte CORNEA-MODEL and these results were evaluated in correlation with in vivo results. The predictions of the optimized LabCyte CORNEA-MODEL eye irritation test methods were highly correlated with in vivo eye irritation (sensitivity 100%, specificity 80.0%, and accuracy 91.8%). These results suggest that the LabCyte CORNEA-MODEL eye irritation test could be useful as an alternative method to the Draize eye test.

  5. Adenoviral Gene Therapy for Diabetic Keratopathy: Effects on Wound Healing and Stem Cell Marker Expression in Human Organ-cultured Corneas and Limbal Epithelial Cells.

    Science.gov (United States)

    Kramerov, Andrei A; Saghizadeh, Mehrnoosh; Ljubimov, Alexander V

    2016-04-07

    The goal of this protocol is to describe molecular alterations in human diabetic corneas and demonstrate how they can be alleviated by adenoviral gene therapy in organ-cultured corneas. The diabetic corneal disease is a complication of diabetes with frequent abnormalities of corneal nerves and epithelial wound healing. We have also documented significantly altered expression of several putative epithelial stem cell markers in human diabetic corneas. To alleviate these changes, adenoviral gene therapy was successfully implemented using the upregulation of c-met proto-oncogene expression and/or the downregulation of proteinases matrix metalloproteinase-10 (MMP-10) and cathepsin F. This therapy accelerated wound healing in diabetic corneas even when only the limbal stem cell compartment was transduced. The best results were obtained with combined treatment. For possible patient transplantation of normalized stem cells, an example is also presented of the optimization of gene transduction in stem cell-enriched cultures using polycationic enhancers. This approach may be useful not only for the selected genes but also for the other mediators of corneal epithelial wound healing and stem cell function.

  6. Herpes simplex virus-specific T cells infiltrate the cornea of patients with herpetic stromal keratitis: no evidence for autoreactive T cells

    NARCIS (Netherlands)

    L. Remeijer (Lies); C.M. Mooy (Cornelia); A.D.M.E. Osterhaus (Albert); G.M.G.M. Verjans (George)

    2000-01-01

    textabstractPURPOSE: Herpetic stromal keratitis (HSK) is a T-cell-mediated inflammatory disease initiated by a herpes simplex virus (HSV) infection of the cornea. Recently, studies in the HSK mouse model have shown that the immunopathogenic T cells are directed against the HSV prot

  7. A Raman scattering and FT-IR spectroscopic study on the effect of the solar radiation in Antarctica on bovine cornea

    Science.gov (United States)

    Yamamoto, Tatsuyuki; Murakami, Naoki; Yoshikiyo, Keisuke; Takahashi, Tetsuya; Yamamoto, Naoyuki

    2010-01-01

    The Raman scattering and FT-IR spectra of the corneas, transported to the Syowa station in Antarctica and exposed to the solar radiation of the mid-summer for four weeks, were studied to reveal that type IV collagen involved in corneas were fragmented. The amide I and III Raman bands were observed at 1660 and 1245 cm -1, respectively, and the amide I and II infrared bands were observed at 1655 and 1545 cm -1, respectively, for original corneas before exposure. The background of Raman signals prominently increased and the ratio of amide II infrared band versus amide I decreased by the solar radiation in Antarctica. The control experiment using an artificial UV lamp was also performed in laboratory. The decline rate of the amide II/amide I was utilized for estimating the degree of fragmentation of collagen, to reveal that the addition of vitamin C suppressed the reaction while the addition of sugars promoted it. The effect of the solar radiation in Antarctica on the corneas was estimated as the same as the artificial UV lamp of four weeks (Raman) or one week (FT-IR) exposure.

  8. Central corneal thickness measurement using ultrasonic pachymetry, rotating scheimpflug camera, and scanning-slit topography exclusively in thin non-keratoconic corneas

    Directory of Open Access Journals (Sweden)

    Mehrdad Mohammadpour

    2016-01-01

    Conclusion: In normal thin corneas, Pentacam demonstrated better agreement with US pachymetry as compared to corrected Orbscan readings. Results achieved by Orbscan were better consistent with US pachymetry using an AF of 0.94. We speculate that a dynamically graded AF in reverse proportion to CCT constitutes a better approach for correcting Orbscan measurements.

  9. Amniotic membrane immobilized poly(vinyl alcohol) hybrid polymer as an artificial cornea scaffold that supports a stratified and differentiated corneal epithelium.

    Science.gov (United States)

    Uchino, Yuichi; Shimmura, Shigeto; Miyashita, Hideyuki; Taguchi, Tetsushi; Kobayashi, Hisatoshi; Shimazaki, Jun; Tanaka, Junzo; Tsubota, Kazuo

    2007-04-01

    Poly(vinyl alcohol) (PVA) is a biocompatible, transparent hydrogel with physical strength that makes it promising as a material for an artificial cornea. In our previous study, type I collagen was immobilized onto PVA (PVA-COL) as a possible artificial cornea scaffold that can sustain a functional corneal epithelium. The cellular adhesiveness of PVA in vitro was improved by collagen immobilization; however, stable epithelialization was not achieved in vivo. To improve epithelialization in vivo, we created an amniotic membrane (AM)-immobilized polyvinyl alcohol hydrogel (PVA-AM) for use as an artificial cornea material. AM was attached to PVA-COL using a tissue adhesive consisting of collagen and citric acid derivative (CAD) as a crosslinker. Rabbit corneal epithelial cells were air-lift cultured with 3T3 feeder fibroblasts to form a stratified epithelial layer on PVA-AM. The rabbit corneal epithelial cells formed 3-5 layers of keratin-3-positive epithelium on PVA-AM. Occludin-positive cells were observed lining the superficial epithelium, the gap-junctional protein connexin43-positive cells was localized to the cell membrane of the basal epithelium, while both collagen IV were observed in the basement membrane. Epithelialization over implanted PVA-AM was complete within 2 weeks, with little inflammation or opacification of the hydrogel. Corneal epithelialization on PVA-AM in rabbit corneas improved over PVA-COL, suggesting the possibility of using PVA-AM as a biocompatible hybrid material for keratoprosthesis. (c) 2006 Wiley Periodicals, Inc.

  10. Development of a serum-free human cornea construct for in vitro drug absorption studies: the influence of varying cultivation parameters on barrier characteristics.

    Science.gov (United States)

    Hahne, Matthias; Reichl, Stephan

    2011-09-15

    The increased use of ophthalmic products in recent years has led to an increased demand for in vitro and in vivo transcorneal drug absorption studies. Cell-culture models of the human cornea can avoid several of the disadvantages of widely used animal experimental models, including ethical concerns and poor standardisation. This study describes the development of a serum-free cultivated, three-dimensional human cornea model (Hemicornea, HC) for drug absorption experiments. The impact of varying cultivation conditions on the corneal barrier function was analysed and compared with excised rabbit and porcine corneas. The HC was cultivated on permeable polycarbonate filters using immortalised human keratocytes and a corneal epithelial cell line. The equivalence to native tissue was investigated through absorption studies using model substances with a wide range of molecular characteristics, including hydrophilic sodium fluorescein, lipophilic rhodamine B and fluorescein isothiocyanate (FITC)-labelled macromolecule dextran. To study the intra-laboratory repeatability and construct cultivation, the permeation studies were performed independently by different researchers. The HC exhibited a permeation barrier in the same range as excised animal corneas, high reproducibility and a lower standard deviation. Therefore, the HC could be a promising in vitro alternative to ex vivo corneal tissues in preclinical permeation studies.

  11. One cornea for two patients: case report Uma córnea para dois pacientes: relato de caso

    Directory of Open Access Journals (Sweden)

    Ljubisa Nikolic

    2010-06-01

    Full Text Available Case reporting the use of one donor cornea for two transplantation procedures: deep anterior lamellar keratoplasty (DALK in a case of an imminent corneal perforation caused by herpetic stromal necrosis, and Descemet stripping with endothelial keratoplasty (DSEK in an eye with pseudophakic bullous keratopathy (PBK. Descemet's membrane (DM, denuded by stromal necrosis, served as the starting point for dissection plane and creation of the recipient bed for DALK. The next steps were excision of the diseased stroma along the edge of trephination, and transplantation of a 400-450 µm thick, manually dissected lamellar graft. The remaining posterior layers of the donor cornea, 100-150 µm thick, were used as a graft in the DSEK procedure for PBK. The integrity of the globe was saved, and best-corrected visual acuity (BCVA of 20/40 was reached after DALK in the eye with an imminent corneal perforation. A subnormal central corneal thickness (CCT of 430 µm did not interfere with corneal shape (43.50 x 45.50 D and function. The graft remained attached and clear after DSEK in the eye with PBK, with BCVA of 20/30 and a CCT of 653 µm. One donor cornea can be used for two lamellar keratoplasties, DALK and DSEK. Although the described obstacles may prevent this approach from becoming widely used, it may prove useful when one is confronted with a need for an urgent anterior lamellar keratoplasty, a long list of cases for DSEK, and a shortage of donor corneas.Relato de caso descrevendo o uso de uma córnea doadora para dois procedimentos de transplante: ceratoplastia anterior lamelar profunda (DALK no caso de uma perfuração corneal iminente causada por necrose estromal por herpes vírus, e ceratoplastia com transplante de endotélio (DSEK no olho com ceratopatia bolhosa em pseudofacia (PBK. A membrana de Descemet (DM, previamente desnudada pela necrose estromal, serviu como ponto de partida para o plano de dissecção e da criação do leito estromal para

  12. Quantification of small fiber pathology in patients with sarcoidosis and chronic pain using cornea confocal microscopy and skin biopsies

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    Oudejans LCJ

    2017-08-01

    Full Text Available Linda CJ Oudejans,1 Marieke Niesters,1 Michael Brines,2 Albert Dahan,1 Monique van Velzen1 1Department of Anesthesiology, Leiden University Medical Center, Leiden, the Netherlands; 2Araim Pharmaceuticals, Inc., Tarrytown, NY, USA Abstract: Small fiber pathology with concomitant chronic neuropathic pain is a common complication of sarcoidosis. The gold standard of diagnosis of small fiber neuropathy (SFN is the quantification of small nerve fibers in skin biopsies in combination with patient history and psychophysical tests; a new technique is the quantification of small nerve fibers in the cornea using cornea confocal microscopy (CCM. Here, we studied small fiber morphology in sarcoidosis patients with neuropathic pain using skin biopsies, CCM, and quantitative sensory testing (QST. Our aim was to construct specific phenotypes of neuropathic pain in sarcoidosis. Fifty-eight patients with a confirmed diagnosis of sarcoidosis and with moderate-to-severe neuropathic pain were tested. Decreased intraepidermal nerve fiber density (IENFD from skin biopsies was found in 28% of patients, and CCM abnormalities were observed in 45% of patients. There was no correlation between CCM and IENFD abnormalities. Eighty-three percent of patients had abnormal thermal detection thresholds, a sign of small fiber dysfunction. Based on the presence or absence of abnormalities in IENFD and CCM, four distinct phenotypes were identified with a distinct homogeneous pattern of somatosensory symptoms. We argue that these distinct phenotypes have a similar mechanistic construct with specific phenotype-specific treatment options. Additionally, our data suggest the presence of patients with length- and nonlength-dependent SFN within this population of sarcoidosis patients. Keywords: chronic pain, sarcoidosis, small fiber neuropathy

  13. LL-37 via EGFR transactivation to promote high glucose-attenuated epithelial wound healing in organ-cultured corneas.

    Science.gov (United States)

    Yin, Jia; Yu, Fu-Shin X

    2010-04-01

    Purpose. Patients with diabetes are at higher risk for delayed corneal reepithelialization and infection. Previous studies indicated that high glucose (HG) impairs epidermal growth factor receptor (EGFR) signaling and attenuates ex vivo corneal epithelial wound healing. The authors investigated the effects of antimicrobial peptide LL-37 on HG-attenuated corneal epithelial EGFR signaling and wound closure. Methods. Human corneal epithelial cells (HCECs) were stimulated with LL-37. Heparin-binding EGF-like growth factor (HB-EGF) shedding was assessed by measuring the release of alkaline phosphatase (AP) in a stable HCEC line expressing HB-EGF-AP. Activation of EGFR, phosphoinositide 3-kinase (PI3K), and extracellular signal-regulated kinases 1/2 (ERK1/2) was determined by Western blot analysis. Corneal epithelial wound closure was assessed in cultured HCECs and porcine corneas. LL-37 expression was determined by immune dot blot. Results. LL-37 induced HB-EGF-AP release and EGFR activation in a dose-dependent manner. LL-37 prolonged EGFR signaling in response to wounding. LL-37 enhanced the closure of a scratch wound in cultured HCECs and partially rescued HG-attenuated wound healing in an EGFR- and a PI3K-dependent manner and restored HG-impaired EGFR signaling in cultured porcine corneas. HG attenuated wounding-induced LL-37 expression in cultured HCECs. Conclusions. LL-37 is a tonic factor promoting EGFR signaling and enhancing epithelial wound healing in normal and high glucose conditions. With both antimicrobial and regenerative capabilities, LL-37 may be a potential therapeutic for diabetic keratopathy.

  14. Three dimensional visualization and fractal analysis of mosaic patches in rat chimeras: cell assortment in liver, adrenal cortex and cornea.

    Science.gov (United States)

    Iannaccone, Stephen; Zhou, Yue; Walterhouse, David; Taborn, Greg; Landini, Gabriel; Iannaccone, Philip

    2012-01-01

    The production of organ parenchyma in a rapid and reproducible manner is critical to normal development. In chimeras produced by the combination of genetically distinguishable tissues, mosaic patterns of cells derived from the combined genotypes can be visualized. These patterns comprise patches of contiguously similar genotypes and are different in different organs but similar in a given organ from individual to individual. Thus, the processes that produce the patterns are regulated and conserved. We have previously established that mosaic patches in multiple tissues are fractal, consistent with an iterative, recursive growth model with simple stereotypical division rules. Fractal dimensions of various tissues are consistent with algorithmic models in which changing a single variable (e.g. daughter cell placement after division) switches the mosaic pattern from islands to stripes of cells. Here we show that the spiral pattern previously observed in mouse cornea can also be visualized in rat chimeras. While it is generally held that the pattern is induced by stem cell division dynamics, there is an unexplained discrepancy in the speed of cellular migration and the emergence of the pattern. We demonstrate in chimeric rat corneas both island and striped patterns exist depending on the age of the animal. The patches that comprise the pattern are fractal, and the fractal dimension changes with the age of the animal and indicates the constraint in patch complexity as the spiral pattern emerges. The spiral patterns are consistent with a loxodrome. Such data are likely to be relevant to growth and cell division in organ systems and will help in understanding how organ parenchyma are generated and maintained from multipotent stem cell populations located in specific topographical locations within the organ. Ultimately, understanding algorithmic growth is likely to be essential in achieving organ regeneration in vivo or in vitro from stem cell populations.

  15. Evaluation of Intrastromal Riboflavin Concentration in Human Corneas after Three Corneal Cross-Linking Imbibition Procedures: A Pilot Study

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    Antonella Franch

    2015-01-01

    Full Text Available Purpose. To compare stromal riboflavin concentration after three corneal cross-linking (CXL imbibition procedures: standard (EpiOff, transepithelial corneal (EpiOn, and iontophoresis-assisted technique (Ionto using 0.1% hypotonic riboflavin phosphate. Methods. Randomized open-label pilot clinical study. Twelve corneas/12 patients with advanced keratoconus were randomly divided into 4 groups for CXL (n=3. The corneas underwent imbibition with standard riboflavin EpiOff and with enhanced riboflavin solution (RICROLIN+ EpiOff, EpiOn, and iontophoresis techniques. Thereafter, deep anterior lamellar keratectomy procedure was performed and the obtained debrided corneal tissues were frozen. The maximal intrastromal riboflavin concentration was measured by high-performance liquid chromatography/mass spectrometry (mcg/dg. Results. The mean stromal concentration of riboflavin was 2.02±0.72 mcg/dg in EpiOff group, 4.33±0.12 mcg/g in EpiOff-RICROLIN+ group, 0.63±0.21 mcg/dg in EpiOn-RICROLIN+ group, and 1.15±0.27 mcg/dg in iontophoresis RICROLIN+ group. A 7-fold decrease in intrastromal riboflavin concentration was observed comparing EpiOn-RICROLIN+ and EpiOff-RICROLIN+ groups. Conclusion. The present pilot study indicates that both transepithelial CXL techniques in combination with hypotonic enhanced riboflavin formulation (RICROLIN+ were still inferior to the standard CXL technique; however, larger clinical studies to further validate the results are needed and in progress.

  16. Three dimensional visualization and fractal analysis of mosaic patches in rat chimeras: cell assortment in liver, adrenal cortex and cornea.

    Directory of Open Access Journals (Sweden)

    Stephen Iannaccone

    Full Text Available The production of organ parenchyma in a rapid and reproducible manner is critical to normal development. In chimeras produced by the combination of genetically distinguishable tissues, mosaic patterns of cells derived from the combined genotypes can be visualized. These patterns comprise patches of contiguously similar genotypes and are different in different organs but similar in a given organ from individual to individual. Thus, the processes that produce the patterns are regulated and conserved. We have previously established that mosaic patches in multiple tissues are fractal, consistent with an iterative, recursive growth model with simple stereotypical division rules. Fractal dimensions of various tissues are consistent with algorithmic models in which changing a single variable (e.g. daughter cell placement after division switches the mosaic pattern from islands to stripes of cells. Here we show that the spiral pattern previously observed in mouse cornea can also be visualized in rat chimeras. While it is generally held that the pattern is induced by stem cell division dynamics, there is an unexplained discrepancy in the speed of cellular migration and the emergence of the pattern. We demonstrate in chimeric rat corneas both island and striped patterns exist depending on the age of the animal. The patches that comprise the pattern are fractal, and the fractal dimension changes with the age of the animal and indicates the constraint in patch complexity as the spiral pattern emerges. The spiral patterns are consistent with a loxodrome. Such data are likely to be relevant to growth and cell division in organ systems and will help in understanding how organ parenchyma are generated and maintained from multipotent stem cell populations located in specific topographical locations within the organ. Ultimately, understanding algorithmic growth is likely to be essential in achieving organ regeneration in vivo or in vitro from stem cell populations.

  17. Confocal microscopy of epithelial and langerhans cells of the cornea in patients using travoprost drops containing two different preservatives.

    Science.gov (United States)

    Marsovszky, László; Resch, Miklós D; Visontai, Zsuzsanna; Németh, János

    2014-07-01

    The recently developed confocal cornea microscopy offers the opportunity to examine pathologies of the cornea and to gain insight into the activity of innate immunity. We aimed to investigate the corneal epithelial and Langerhans cell (LC) densities along with dry eye parameters in primary open-angle glaucoma (POAG) subjects, treated with either of two commercially available travoprost 0.004 % topical medications containing different preservatives. (1: benzalkonium chloride 0.015 % (TravBAK) and 2: polyquaternium-1 (PQ) 0.001 % (TravPQ). Consecutive case series of nineteen POAG patients on TravBAK (mean age: 64.8 ± 13.6 years), nineteen POAG patients on TravPQ (mean age: 66.8 ± 11.3 years) and nineteen age-matched healthy control subjects (63.8 ± 8.2 years). Ocular surface disease index (OSDI), lid parallel conjunctival folds (LIPCOF), Schirmer test (ST) and tear break up time (TBUT) were assessed, and then corneal epithelial and LC densities were investigated with confocal microscopy. Tear production was significantly reduced in both glaucoma patient groups compared to healthy individuals (p < 0.05). TBUT was significantly reduced and epithelial cell densities were significantly greater in patients treated with TravBAK compared to healthy individuals (p < 0.05 for all). LC densities were greater in both glaucoma groups compared to control subjects (p < 0.05 for all). Travoprost therapy may compromise ocular surface. The limited alertness of the corneal immune system found in patients with TravPQ can be considered as indicators of a less disturbed ocular surface and better controlled corneal homeostasis.

  18. OAS/PKR Pathways and α/β TCR+ T Cells are Required for Ad: IFN-γ Inhibition of HSV-1 in Cornea1

    Science.gov (United States)

    Austin, Bobbie Ann; Halford, William P.; Williams, Bryan R. G.; Carr, Daniel J. J.

    2007-01-01

    An adenoviral vector containing the muIFN-γ transgene (Ad:IFN-γ) was evaluated for its capacity to inhibit HSV-1. To measure effectiveness, viral titers were analyzed in cornea and trigeminal ganglia (TG) during acute ocular HSV-1 infection. Ad: IFN-γ potently suppressed HSV-1 replication in a dose-dependent fashion, requiring IFN-γ R. Moreover, Ad:IFN-γ was effective when delivered -72 and -24 h prior to infection as well as 24 h post infection. Associated with anti-viral opposition, TG from Ad: IFN-γ transduced mice harbored fewer T cells. Also related to T cell involvement, Ad:IFN-γ was effective but attenuated in TG from α/β TCR deficient mice. In corneas, α/β TCR+ T cells were obligatory for protection against viral multiplication. Type I IFN involvement amid anti-viral efficacy of Ad: IFN-γ was further investigated because type I and II IFN pathways have synergistic anti-HSV-1 activity. Ad:IFN-γ inhibited viral reproduction in corneas and TG from IFN-α/β R deficient (CD118 −/−) mice, although viral titers were 2–3 fold higher in cornea and TG, compared to wild type. The absence of IFN-stimulated anti-viral proteins, 2’-5’ oligoadenylate synthetase/RNase L and ds RNA dependent protein kinase R, completely eliminated the anti-viral effectiveness of Ad:IFN-γ. Collectively, the results demonstrate: (1) nonexistence of type I IFN R does not abolish defense of Ad:IFN-γ against HSV-1; (2) anti-viral pathways, OAS/RNase L and PKR are mandatory; and (3) α/β TCR+ T cells are compulsory for Ad: IFN-γ effectiveness against HSV-1 in cornea but not in TG. PMID:17404299

  19. Poly (ε-caprolactone nanofibrous ring surrounding a polyvinyl alcohol hydrogel for the development of a biocompatible two-part artificial cornea

    Directory of Open Access Journals (Sweden)

    Bakhshandeh H

    2011-07-01

    Full Text Available Haleh Bakhshandeh1, Masoud Soleimani2, Saied Shah Hosseini3, Hassan Hashemi3, Iman Shabani4, Abbas Shafiee5, Amir Houshang Behesht Nejad6, Mohammad Erfan1, Rassoul Dinarvand7, Fatemeh Atyabi71Department of Pharmaceutics, School of Pharmacy, Shaheed Beheshti Medical University, Tehran, Iran; 2Hematology Department, Faculty of Medical Science, Tarbiat Modares University, Tehran, Iran; 3Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran; 4Nanotechnology and Tissue Engineering Department, Stem Cell Technology Research Center, Tehran, Iran; 5Stem Cell Biology Department, Stem Cell Technology Research Center, Tehran, Iran; 6Ophthalmology Department, Tehran University of Medical Sciences, Tehran, Iran; 7Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, IranAbstract: The study aimed to fabricate and characterize a 2-part artificial cornea as a substitute for penetrating keratoplasty in patients with corneal blindness. The peripheral part of the artificial cornea consisted of plasma-treated electrospun poly (ε-caprolactone (PCL nanofibers, which were attached to a hydrogel disc of polyvinyl alcohol (PVA as a central optical part. The physical properties of the prepared artificial cornea, including morphology, mechanical properties, light transmittance, and contact angle, were assessed. Cell attachment and proliferation studies were performed on rabbit limbal stem cells. The SEM image of the polymeric system showed that the peripheral part formed a highly porous scaffold that could facilitate tissue biointegration. Assessment of the mechanical properties of the peripheral nanofibrous part and the hydrogel optical part showed suitable elasticity. Young’s modulus values of the electrospun PCL skirt and PVA hydrogel core were 7.5 and 5.3 MPa, respectively, which is in line with the elasticity range of natural human cornea (0.3–7 MPa. The light transmittance of the central part was >85

  20. Estudo comparativo entre duas plataformas para realização de Lasik personalizado para correção de miopia e astigmatismo: Alcon CustomCornea® versus Bausch & Lomb Zyoptix® Wavefront-Guided Lasik for low to moderate myopia: CustomCornea® versus Zyoptix®

    Directory of Open Access Journals (Sweden)

    Telma Pereira Barreiro

    2009-08-01

    Full Text Available OBJETIVO: Comparar os resultados obtidos após o Lasik personalizado utilizando duas plataformas diferentes. MÉTODOS: Estudo prospectivo, randomizado com 50 pacientes míopes submetidos a cirurgia refrativa em ambos os olhos. Foram selecionados para o estudo, pacientes com equivalente esférico semelhante entre os olhos. Todos foram submetidos a Lasik bilateral e simultâneo, sendo que um olho foi operado pela plataforma CustomCornea® e o outro pela Zyoptix®. Acuidade visual sem e com correção, refração dinâmica e estática, medida das aberrações oculares, teste de sensibilidade ao contraste foram realizados no período pré-operatório e pós-operatório de 1, 3 e 6 meses. RESULTADOS: No período pré-operatório a média do equivalente esférico era de -3,29 ± 1,56 D no grupo CustomCornea® e de -3,22 ± 1,50 D no Zyoptix® (p=0,267. No sexto mês de pós-operatório, a média do equivalente esférico no grupo CustomCornea® era de -0,077 ± 0,23 D e -0,282 ± 0,30 D no Zyoptix® (p 20/20 foi alcançada em 86% dos olhos no grupo CustomCornea® e 70% no grupo Zyoptix® (p=0,094. Nenhum paciente perdeu duas ou mais linhas da melhor acuidade visual corrigida. Cem por cento dos olhos CustomCornea® e 88% dos Zyoptix® ficaram entre ± 0,50 D da emetropia (p=0,014*. Melhora da sensibilidade ao contraste em todas as frequências espaciais testadas foi observada em ambos os grupos. A aberração esférica apresentou aumento em ambos os grupos, porém este foi estatisticamente maior na plataforma Zyoptix® (pPURPOSE: To compare the visual and clinical outcomes of Wavefront-guided laser in situ keratomileusis (Lasik with Alcon CustomCornea® and Zyoptix® systems. METHODS: A prospective, randomized, masked and bilateral study was conducted. Fifty patients with preoperative spherical equivalent ranging from -1.00 to -6.50 D were enrolled for customized ablation in both eyes. All of them were submitted to Lasik CustomCornea® treatment in one

  1. Coloured cornea replacements with anti-infective properties: expanding the safe use of silver nanoparticles in regenerative medicine

    Science.gov (United States)

    Alarcon, E. I.; Vulesevic, B.; Argawal, A.; Ross, A.; Bejjani, P.; Podrebarac, J.; Ravichandran, R.; Phopase, J.; Suuronen, E. J.; Griffith, M.

    2016-03-01

    Despite the broad anti-microbial and anti-inflammatory properties of silver nanoparticles (AgNPs), their use in bioengineered corneal replacements or bandage contact lenses has been hindered due to their intense yellow coloration. In this communication, we report the development of a new strategy to pre-stabilize and incorporate AgNPs with different colours into collagen matrices for fabrication of corneal implants and lenses, and assessed their in vitro and in vivo activity.Despite the broad anti-microbial and anti-inflammatory properties of silver nanoparticles (AgNPs), their use in bioengineered corneal replacements or bandage contact lenses has been hindered due to their intense yellow coloration. In this communication, we report the development of a new strategy to pre-stabilize and incorporate AgNPs with different colours into collagen matrices for fabrication of corneal implants and lenses, and assessed their in vitro and in vivo activity. Electronic supplementary information (ESI) available: Collagen hydrogel, moulded as a cornea, prepared containing collagen protected AgNPs and representative images for collagen hydrogels, moulded as corneas, containing Blue AgNPs either unprotected or protected with LL37-SH; representative TEM images for Green-1 AgNPs prepared in this work; changes on surface plasmon band after synthesis for Green-2 AgNPs without LL37-SH; representative picture of the powder obtained for Green-1 AgNPs capped with LL37-SH after 72 h lyophilization, see main text; representative TEM images for Blue and Green-1 AgNPs prepared in this work; absorption spectra for the supernatants for collagen hydrogels containing Blue AgNPs; absorbance at 600 nm of PAO1 cultures prepared in 25% LB media incubated for 14 h at 37 °C in the presence of different concentrations of AgNPs, Green-1 or Blue, or silver nitrate; HECC cell density (cells per cm2) measured on gels with and without silver nitrate after 1 day of cell incubation; total silver concentration

  2. Simultaneous quantification of gatifloxacin, moxifloxacin, and besifloxacin concentrations in cornea and aqueous humor by LC-QTOF/MS after topical ocular dosing.

    Science.gov (United States)

    Domingos, Luisa C; Moreira, Matheus Vilardo L; Keller, Kelly M; Viana, Fernando Antônio B; Melo, Marília M; Soto-Blanco, Benito

    The fourth-generation fluoroquinolones are widely used as ophthalmic antimicrobials. This study aimed to validate a new analytical technique for simultaneous quantification of gatifloxacin, moxifloxacin, and besifloxacin concentrations in the cornea and aqueous humor by liquid chromatography (LC) coupled to quadrupole time-of-flight mass spectrometry (QTOF/MS) at 10min and 1h after instillation of topical ophthalmic antimicrobial suspensions. It was used twenty-two male dogs without ocular lesions verified by ophthalmic and histologic examinations. Methanol:water (4:1) was used for the extraction procedure for cornea and acetonitrile:water (4:1) was used for aqueous humor. The chromatographic separations were carried out on a C18 column with a linear gradient of water and methanol, both containing 0.1% formic acid. The total chromatographic run time was 4min. Mass spectrometry analyses were performed on a Xevo™ G2-S QTof tandem mass spectrometer, operated in a positive ion electrospray ionization (ESI+) mode. The retention times were approximately 1.42min for gatifloxacin, 1.87min for moxifloxacin, and 3.01min for besifloxacin. No interference peak was detected for the three tested antimicrobials in samples obtained from both cornea and aqueous humor, ensuring that the peak response was exclusive to the analyte of interest. The limit of detection for the three antimicrobials was 0.11μg/mL and the limit of quantification was 0.42μg/mL for both cornea and aqueous humor samples. At both time points post instillation of the three antimicrobials, moxifloxacin had the highest corneal concentration and besifloxacin demonstrated the highest concentration in the aqueous humor. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Determining the Depth of Injury in Bioengineered Tissue Models of Cornea and Conjunctiva for the Prediction of All Three Ocular GHS Categories.

    Directory of Open Access Journals (Sweden)

    Michaela Zorn-Kruppa

    Full Text Available The depth of injury (DOI is a mechanistic correlate to the ocular irritation response. Attempts to quantitatively determine the DOI in alternative tests have been limited to ex vivo animal eyes by fluorescent staining for biomarkers of cell death and viability in histological cross sections. It was the purpose of this study to assess whether DOI could also be measured by means of cell viability detected by the MTT assay using 3-dimensional (3D reconstructed models of cornea and conjunctiva. The formazan-free area of metabolically inactive cells in the tissue after topical substance application is used as the visible correlate of the DOI. Areas of metabolically active or inactive cells are quantitatively analyzed on cryosection images with ImageJ software analysis tools. By incorporating the total tissue thickness, the relative MTT-DOI (rMTT-DOI was calculated. Using the rMTT-DOI and human reconstructed cornea equivalents, we developed a prediction model based on suitable viability cut-off values. We tested 25 chemicals that cover the whole range of eye irritation potential based on the globally harmonized system of classification and labelling of chemicals (GHS. Principally, the MTT-DOI test method allows distinguishing between the cytotoxic effects of the different chemicals in accordance with all 3 GHS categories for eye irritation. Although the prediction model is slightly over-predictive with respect to non-irritants, it promises to be highly valuable to discriminate between severe irritants (Cat. 1, and mild to moderate irritants (Cat. 2. We also tested 3D conjunctiva models with the aim to specifically address conjunctiva-damaging substances. Using the MTT-DOI method in this model delivers comparable results as the cornea model, but does not add additional information. However, the MTT-DOI method using reconstructed cornea models already provided good predictability that was superior to the already existing established in vitro/ex vivo

  4. Corneal thickness changes during corneal collagen cross-linking with UV-A irradiation and hypo-osmolar riboflavin in thin corneas

    Directory of Open Access Journals (Sweden)

    Belquiz Amaral Nassaralla

    2013-06-01

    Full Text Available PURPOSE: To evaluate the thinnest corneal thickness changes during and after corneal collagen cross-linking treatment with ultraviolet-A irradiation, using hypo-osmolar riboflavin solution in thin corneas. METHODS: Eighteen eyes of 18 patients were included in this study. After epithelium removal, iso-osmolar 0.1% riboflavin solution was instilled to the cornea every 3 minutes for 30 minutes. Hypo-osmolar 0.1% riboflavin solution was then applied every 20 seconds for 5 minutes or until the thinnest corneal thickness reached 400 µm. Ultraviolet-A irradiation was performed for 30 minutes. During irradiation, iso-osmolar 0.1% riboflavin drops were applied every 5 minutes. Ultrasound pachymetry was performed at approximately the thinnest point of the cornea preoperatively, after epithelial removal, after iso-osmolar riboflavin instillation, after hypo-osmolar riboflavin instillation, after ultraviolet-A irradiation, and at 1, 6 and 12 months after treatment. RESULTS: Mean preoperative thinnest corneal thickness was 380 ± 11 µm. After epithelial removal it decreased to 341 ± 11 µm, and after 30 minutes of iso-osmolar 0.1% riboflavin drops, to 330 ± 7.6 µm. After hypo-osmolar 0.1% riboflavin drops, mean thinnest corneal thickness increased to 418 ± 11 µm. After UVA irradiation, it was 384 ± 10 µm. At 1, 6 and 12 months after treatment, it was 372 ± 10 µm, 381 ± 12.7, and 379 ± 15 µm, respectively. No intraoperative, early postoperative, or late postoperative complications were noted. CONCLUSIONS: Hypo-osmolar 0.1% riboflavin solution seems to be effective for swelling thin corneas. The swelling effect is transient and short acting. Corneal thickness should be monitored throughout the procedure. Larger sample sizes and longer follow-up are required in order to make meaningful conclusions regarding safety.

  5. Chronic Electromagnetic Exposure at Occupational Safety Level Does Not Affect the Metabolic Profile nor Cornea Healing after LASIK Surgery

    Directory of Open Access Journals (Sweden)

    David Crouzier

    2014-01-01

    Full Text Available LASIK eye surgery has become a very common practice for myopic people, especially those in the military. Sometimes undertaken by people who need to keep a specific medical aptitude, this surgery could be performed in secret from the hierarchy and from the institute medical staff. However, even though the eyes have been previously described as one of the most sensitive organs to electromagnetic fields in the human body, no data exist on the potential deleterious effects of electromagnetic fields on the healing eye. The consequences of chronic long-lasting radar exposures at power density, in accordance with the occupational safety standards (9.71 GHz, 50 W/m2, were investigated on cornea healing. The metabolic and clinical statuses after experimental LASIK keratotomy were assessed on the different eye segments in a New Zealand rabbit model. The analysis methods were performed after 5 months of exposure (1 hour/day, 3 times/week. Neither clinical or histological examinations, nor experimental data, such as light scattering, 1H-NMR HRMAS metabolomics, 13C-NMR spectra of lipidic extracts, and antioxidant status, evidenced significant modifications. It was concluded that withdrawing the medical aptitude of people working in electromagnetic field environments (i.e., radar operators in the navy after eye surgery was not justified.

  6. Combined use of borneol or menthol with labrasol promotes penetration of baicalin through rabbit cornea in vitro.

    Science.gov (United States)

    Huang, Lei; Bai, Jianhai; Yang, Hongbin; Liu, Jingjing; Cui, Hao

    2015-01-01

    The permeability of most drugs through the eyes is very limited, so finding safe and effective penetration enhancers is of high importance in current ophthalmology research. In this paper, we use a new approach that integrates Chinese and Western medicine to improve the corneal permeability of baicalin, a water- and fat-insoluble target drug, in vitro. Rabbits were divided into three groups. The first group was dosed with borneol (0.05%, 0.1%). menthol (0.1%, 0.2%), or Labrasol (1%, 2%) individually, the second was dosed with a combination of Labrasol with either borneol or menthol, and the third group received a control treatment. Compared with the control treatment, borneol, menthol, or Labrasol alone clearly improved the permeability of baicalin in vitro. Furthermore, the penetrating effects were significantly increased by combining the application of Labrasol with menthol or borneol. Among the various combined penetration enhancers, 0.1% borneol with 2% Labrasol achieved the best apparent permeability, approximately 16.35 times that of the control. Additionally, the calculation of corneal hydration level and the Draize test demonstrated the safety of these penetration enhancers to the rabbit corneas in vivo. This study confirms that the combined use of borneol or menthol, compounds both derived from Chinese herbs, with Labrasol can improve the corneal permeability of water- and fat-insoluble drugs.

  7. Late Stage of Corneal Decompensation Caused by Progressive Keratoconus: Can We Treat It and Save the Cornea?

    Directory of Open Access Journals (Sweden)

    Igor Knezović

    2015-01-01

    Full Text Available Aim. To report a case of 40-year-old male with progressive bilateral keratoconus who had undergone transepithelial phototherapeutic keratectomy (TE-PTK and corneal collagen cross-linking (CXL using hypoosmolar riboflavin solution in a same day procedure. Methods. Eye examination showed that UCDVA on both eyes was 0,01 according to Snellen charts, and slit lamp biomicroscopy showed paracentral diffuse intrastromal corneal haze. Anterior OCT marked stromal hyperreflective zones and localized paracentral thinning of the cornea. Scheimpflug tomography noted keratoconus stages III-IV on both eyes. After 40/35 microns TE-PTK, a CXL was performed for 30 minutes using hypoosmolar riboflavin solution. The left eye was treated first and the right eye 1 month after. Follow-up period was 10 months. Results. One month after the treatment both eyes showed improvement in corneal topography and the UCDVA was better. Eight months after the treatment BSCVA improved to 0,6 in both eyes using Rose K2 contact lenses and remained stable. Conclusion. TE-PTK and CXL using hypotonic riboflavin solution as a same day procedure have been shown to be a safe and promising method in this case of progressive keratoconus. It was necessary to consider certain parameters that could influence the safety and the final outcome of this combined protocol.

  8. Effect of the Multiglycoside of Tripterygium Wilfordii Hookf.(Tii)on Cornea Allograft Rejection Model in Rabbit

    Institute of Scientific and Technical Information of China (English)

    ZhijieLi; ChenLi

    1995-01-01

    Purpose:Toexamine the effect of Tii treatment of cornea graft survival in a rab-bit model.Methods:Tii was administrated orally after eccentrical corneal transplantation.Survival times were determined by biomicroscopy.Cytotoxic T lymphocytes(CTL)and delayed-type hypersensitivity(DTH)responses to donor alloantigens were assessed at ady 16after heterotopic corneal grafts.Results:Administration of Tii reduced the incidence and prologed the graft sur-vival time.Both CTLand DTH responses to donor alloantigens were severely ed-pressed in hosts treated with Tii.However,combination of Tii and cyclosporine further enhanced the immunosuppressive effects described above.Conclusions:Tii is a potent immunosuppressant with the ability to prolong allo-graft survival in the rabbit penetrating keratoplasty model and may have coordi-native effects with CsA through different mechanisms.Further studies are neces-sary to define any potentially coordinative role in the prevention of allograft rejec-tion in human keratoplasty.Eye Science 1995;11:168-172.

  9. Chronic Electromagnetic Exposure at Occupational Safety Level Does Not Affect the Metabolic Profile nor Cornea Healing after LASIK Surgery.

    Science.gov (United States)

    Crouzier, David; Dabouis, Vincent; Gentilhomme, Edgar; Vignal, Rodolphe; Bourbon, Fréderic; Fauvelle, Florence; Debouzy, Jean-Claude

    2014-01-01

    LASIK eye surgery has become a very common practice for myopic people, especially those in the military. Sometimes undertaken by people who need to keep a specific medical aptitude, this surgery could be performed in secret from the hierarchy and from the institute medical staff. However, even though the eyes have been previously described as one of the most sensitive organs to electromagnetic fields in the human body, no data exist on the potential deleterious effects of electromagnetic fields on the healing eye. The consequences of chronic long-lasting radar exposures at power density, in accordance with the occupational safety standards (9.71 GHz, 50 W/m(2)), were investigated on cornea healing. The metabolic and clinical statuses after experimental LASIK keratotomy were assessed on the different eye segments in a New Zealand rabbit model. The analysis methods were performed after 5 months of exposure (1 hour/day, 3 times/week). Neither clinical or histological examinations, nor experimental data, such as light scattering, (1)H-NMR HRMAS metabolomics, (13)C-NMR spectra of lipidic extracts, and antioxidant status, evidenced significant modifications. It was concluded that withdrawing the medical aptitude of people working in electromagnetic field environments (i.e., radar operators in the navy) after eye surgery was not justified.

  10. KTCNlncDB—a first platform to investigate lncRNAs expressed in human keratoconus and non-keratoconus corneas

    Science.gov (United States)

    Szcześniak, Michał W.; Kabza, Michal; Karolak, Justyna A.; Rydzanicz, Malgorzata; Nowak, Dorota M.; Ginter-Matuszewska, Barbara; Polakowski, Piotr; Ploski, Rafal; Szaflik, Jacek P.; Gajecka, Marzena

    2017-01-01

    Keratoconus (KTCN, OMIM 148300) is a degenerative eye disorder characterized by progressive stromal thinning that leads to a conical shape of the cornea, resulting in optical aberrations and even loss of visual function. The biochemical background of the disease is poorly understood, which motivated us to perform RNA-Seq experiment, aimed at better characterizing the KTCN transcriptome and identification of long non-coding RNAs (lncRNAs) that might be involved in KTCN etiology. The in silico functional studies based on predicted lncRNA:RNA base-pairings led us to recognition of a number of lncRNAs possibly regulating genes with known or plausible links to KTCN. The lncRNA sequences and data regarding their predicted functions in controlling the RNA processing and stability are available for browse, search and download in KTCNlncDB (http://rhesus.amu.edu.pl/KTCNlncDB/), the first online platform devoted to KTCN transcriptome. Database URL: http://rhesus.amu.edu.pl/KTCNlncDB/ PMID:28077570

  11. Dr John Nottingham's 1854 Landmark Treatise on Conical Cornea Considered in the Context of the Current Knowledge of Keratoconus.

    Science.gov (United States)

    Gokul, Akilesh; Patel, Dipika V; McGhee, Charles N J

    2016-05-01

    John Nottingham has been widely credited with the first accurate description of keratoconus in his treatise on conical cornea, published in 1854. Contained within the 270-page treatise are accounts and theories of keratoconus postulated by authors such as Scarpa, von Carion, von Ammon, and Mackenzie, synthesized by Nottingham in a treatise containing his own original observations. Nottingham's work delves deeply into keratoconus, with coverage reminiscent of a modern review, albeit in a far less succinct manner. He extensively describes the epidemiology, clinical presentation, underlying cause, and treatment of keratoconus. However, the concepts put forth are limited largely by the contemporary lack of understanding of the underlying anatomy and physiology of the eye, and the observations, by technological limitations. He postulates a similar treatment algorithm to that used today; optical devices being the management option of choice in the mild stages with surgery being a last resort. None of the surgical methods discussed are used in the modern era, but he does make reference to the possible efficacy of corneal transplantation. Nottingham's treatise was published over 160 years ago, yet his ideas and observations are surprisingly accurate. It is very possible that he was the first person to publish an accurate, comprehensive description of keratoconus.

  12. Tissue engineering of corneal stromal layer with dermal fibroblasts: phenotypic and functional switch of differentiated cells in cornea.

    Science.gov (United States)

    Zhang, Yan Qing; Zhang, Wen Jie; Liu, Wei; Hu, Xiao Jie; Zhou, Guang Dong; Cui, Lei; Cao, Yilin

    2008-02-01

    Previously, we successfully engineered a corneal stromal layer using corneal stromal cells. However, the limited source and proliferation potential of corneal stromal cells has driven us to search for alternative cell sources for corneal stroma engineering. Based on the idea that the tissue-specific environment may alter cell fate, we proposed that dermal fibroblasts could switch their phenotype to that of corneal stromal cells in the corneal environment. Thus, dermal fibroblasts were harvested from newborn rabbits, seeded on biodegradable polyglycolic acid (PGA) scaffolds, cultured in vitro for 1 week, and then implanted into adult rabbit corneas. After 8 weeks of implantation, nearly transparent corneal stroma was formed, with a histological structure similar to that of its native counterpart. The existence of cells that had been retrovirally labeled with green fluorescence protein (GFP) demonstrated the survival of implanted cells. In addition, all GFP-positive cells that survived expressed keratocan, a specific marker for corneal stromal cells, and formed fine collagen fibrils with a highly organized pattern similar to that of native stroma. However, neither dermal fibroblast-PGA construct pre-incubated in vitro for 3 weeks nor chondrocyte-PGA construct could form transparent stroma. The results demonstrated that neonatal dermal fibroblasts could switch their phenotype in the new tissue environment under restricted conditions. The functional restoration of corneal transparency using dermal fibroblasts suggests that they could be an alternative cell source for corneal stroma engineering.

  13. Label-free SHG imaging and spectral FLIM of corneas using a sub-15 fs laser microscope

    Science.gov (United States)

    Batista, Ana; Breunig, Hans Georg; Uchugonova, Aisada; Seitz, Berthold; Morgado, António Miguel; König, Karsten

    2014-02-01

    Alterations to the corneal cell metabolism or to the structural organization of collagen fibrils occur in several corneal and systemic pathologies. In this work we resort to multiphoton microscopy corneal imaging to achieve a characterization of the corneal state. Using fluorescence lifetime imaging microscopy (FLIM) the assessment of the metabolic state of corneal cells is possible, whereas second harmonic generation (SHG) imaging can be used to assess corneal structural alterations. A sub-15 fs near-infrared laser source with a broad excitation spectrum was used for SHG imaging and FLIM. The broad spectrum allows simultaneous excitation of both metabolic co-factors. The signals were collected by a photomultiplier tubes (PMT) detector with 16 simultaneous recording channels, which allowed the separation of fluorophores autofluorescence based on their emission wavelengths. We were able to successfully image ex-vivo human and porcine cornea at multiple depths. Simultaneous NADH and flavin autofluorescence, SHG of collagen fibrils, and stroma autofluorescence imaging was performed which may in future allow an improved characterization of the metabolic and structural alterations of the corneal tissue due to pathophysiological conditions. This would be an important step towards a better understanding of corneal dystrophies and systemic metabolic disorders.

  14. Expressions of matrix metalloproteinases-1 and -9 and opioid growth factor in rabbit cornea after lamellar keratectomy and treatment with 1% nalbuphine

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    Miguel Ladino Silva

    2015-06-01

    Full Text Available ABSTRACT Purposes: To evaluate the effects of nalbuphine 1% on the expression of metalloproteinase 1 (MMP-1, metalloproteinase 9 (MMP-9, and opioid growth factor (OGF in rabbit corneas after lamellar keratectomy. Methods: The rabbits were assigned to two groups: group nalbuphine (GN, n=30, which received 30 µL of nalbuphine 1% in 4 daily applications at regular intervals until corneal epithelialization, and group control (GC, n=30, which received physiological saline solution under the same conditions adopted in GN. The corneas were collected for immunohistochemistry on days 1, 3, 5, 7, and 9 after lamellar keratectomy, and the expressions of MMP-1, MMP-9, and OGF were analyzed. Results: The expressions of MMP-1 and MMP-9 increased until day 5 of the evaluation, with no differences observed between GN and GC (p>0.05. On days 7 and 9, significant reductions were observed in the expression of MMP-1 (p0.05. The expression of OGF was constant in all periods (p>0.05, restricted to the corneal epithelium, and there was no difference between the groups (p>0.05. Conclusions: The study results showed that nalbuphine 1% did not alter the expression patterns of MMP-1, MMP-9, and OGF in rabbit corneas after lamellar keratectomy.

  15. Simultaneous imaging and measurement of tensile stress on cornea by using a common-path optical coherence tomography system with an external contact reference

    Institute of Scientific and Technical Information of China (English)

    Utkarsh Sharma; Jin U. Kang

    2008-01-01

    The objective of this study is to demonstrate that tensile stress resulting due to applied force on cornea can be accurately measured by using a time-domain common-path optical coherence tomography (OCT) system with an external contact reference. The unique design of the common-path OCT is utilized to set up an imaging system in which a chicken eye is placed adjacent to a glass plate serving as the external reference plane for the imaging system. As the force is applied to the chicken eye, it presses against the reference glass plate. The modified OCT image obtained is used to calculate the size of contact area, which is then used to derive the tensile stress on the cornea. The drop in signal levels upon contact of reference glass plate with the tissue are extremely sharp because of the sharp decline in reference power levels itself, thus providing us with an accurate measurement of contact area. The experimental results were in good agreement with the numerical predictions. The results of this study might be useful in providing new insights and ideas to improve the precision and safety of currently used ophthalmic surgical techniques. This research outlines a method which could be used to provide high resolution OCT images and a precise feedback of the forces applied to the cornea simultaneously.

  16. Effect of a pulsed magnetic field on permeability of the cornea and sorption properties of the tissue structures and refractive media of the eye

    Energy Technology Data Exchange (ETDEWEB)

    Skrinnik, A.V.

    1986-03-01

    The author attempts to obtain direct proof of increased permeability of the cornea and enhanced sorption properties of the tissue structures and refractive media of the eye under the influence of a pulsed magnetic field (MF). In the course of the investigation, the method of radioactive indication of two substances (/sup 35/S-streptomycin and /sup 75/Se-methionine), widely used in opthalmologic practice, was used. The radioactivity of the working solution of the preparations was 300,000 cpm in 0.1 ml. Changes in the permeability of the cornea were assessed on the basis of changes in radioactivity of the aqueous humor. The concentration of /sup 35/S-streptomycin in aqueous humor of the animals immediately after exposure to MF was significantly higher than in the control. Analysis of permeability of the cornea for /sup 75/Se-methionine also showed increased penetration of radioactivity into the aqueous. The results are evidence of the greater penetrating power of /sup 75/Se-methionine.

  17. Distribution of Young's modulus in porcine corneas after riboflavin/UVA-induced collagen cross-linking as measured by atomic force microscopy.

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    Jan Seifert

    Full Text Available Riboflavin/UVA-induced corneal collagen cross-linking has become an effective clinical application to treat keratoconus and other ectatic disorders of the cornea. Its beneficial effects are attributed to a marked stiffening of the unphysiologically weak stroma. Previous studies located the stiffening effect predominantly within the anterior cornea. In this study, we present an atomic force microscopy-derived analysis of the depth-dependent distribution of the Young's modulus with a depth resolution of 5 µm in 8 cross-linked porcine corneas and 8 contralateral controls. Sagittal cryosections were fabricated from every specimen and subjected to force mapping. The mean stromal depth of the zone with effective cross-linking was found to be 219 ± 67 µm. Within this cross-linked zone, the mean Young's modulus declined from 49 ± 18 kPa at the corneal surface to 46 ± 17 kPa, 33 ± 11 kPa, 17 ± 5 kPa, 10 ± 4 kPa and 10 ± 4 kPa at stromal depth intervals of 0-50 µm, 50-100 µm, 100-150 µm, 150-200 µm and 200-250 µm, respectively. This corresponded to a stiffening by a factor of 8.1 (corneal surface, 7.6 (0-50 µm, 5.4 (50-100 µm, 3.0 (100-150 µm, 1.6 (150-200 µm, and 1.5 (200-250 µm, when compared to the Young's modulus of the posterior 100 µm. The mean Young's modulus within the cross-linked zone was 20 ± 8 kPa (2.9-fold stiffening, while it was 11 ± 4 kPa (1.7-fold stiffening for the entire stroma. Both values were significantly distinct from the mean Young's modulus obtained from the posterior 100 µm of the cross-linked corneas and from the contralateral controls. In conclusion, we were able to specify the depth-dependent distribution of the stiffening effect elicited by standard collagen cross-linking in porcine corneas. Apart from determining the depth of the zone with effective corneal cross-linking, we also developed a method that allows for atomic force microscopy-based measurements of gradients of Young's modulus in soft

  18. The non-surgical therapy of fungal cornea ulcer%真菌性角膜溃疡药物治疗体会

    Institute of Scientific and Technical Information of China (English)

    程昕; 谷树严

    2008-01-01

    Objective To summarize curative effect of the non-surgical operations cured the fungal cornea ulcer.Methods 68 inpatients (68 eyes) of the fungal cornea ulcer were treated with medicine locally and systemically.To analyze the curative effect of medication in fungal cornea ulcer.Result The cure rate of non-surgical operation treatment was 36.76%,the improvement rate is 27.94%,the inefficacious rate is 35.29%,2 cases were relapsed.Conclusions The non-surgical operation treatment is the effective method of cure the fungal cornea ulcer.Broad spectrum antifungal agents,especially the polyene and triazole,is efficacious drug to fungal cornea ulcer.The curative effect is conspicuous to the low-grade cases.The refractory cases should be treated with surgical operation.%目的 评价真菌性角膜溃疡非手术治疗的效果.方法 对68例68眼真菌性角膜溃疡患者,采用局部、全身药物治疗等方法的疗效进行回顾性分析,总结非手术方法治疗真菌性角膜溃疡的效果.结果 68例真菌性角膜溃疡患者经非手术治疗,治愈25只眼,好转19只眼,无效24只眼,复发2只眼.结论 非手术治疗方法是治疗真菌性角膜溃疡的一种有效的方法.广谱抗真菌药物多烯类与三唑类药物局部及全身联合治疗真菌性角膜溃疡有效,尤其对溃疡面积小、浸润浅者效果好,复发率低.对于非手术治疗无效的重症患者需行穿透性角膜移植手术治疗.

  19. LASIK后角膜瓣皱褶和折叠的处理%Management of folds and striae in the cornea flap after laser in situ keratomileusis,

    Institute of Scientific and Technical Information of China (English)

    刘云川; 吴欣怡; 张丽; 马蓉; 崔迎春; 王洪娟

    2008-01-01

    目的 探讨准分子激光原位角膜磨镶术(laser in situ keratomileusis,LASIK)后早期角膜瓣皱褶和折叠的有效处理方法.方法 对LASIK术后11例角膜瓣皱褶的原因及处理进行回顾性分析.所有的患者需经手术重新复位,在显微镜下采用去离子水冲洗角膜瓣加戴角膜接触镜24 h.术后观察角膜瓣状况、屈光变化、裸眼视力和最佳矫正视力.结果 经过处理的所有患者裸眼视力均达到或超过术前最佳矫正视力.角膜透明,未见明显皱褶,角膜瓣位置正常,无上皮植入.结论 角膜瓣皱褶和折叠是LASIK术后较严重的并发症.早期诊断和正确快速的处理是获得最佳视力的关键.用去离子水重新复位角膜瓣并佩戴角膜接触镜治疗LASIK术后早期角膜瓣皱褶和折叠是安全简单有效的方法.%Objective To investigate the efficient treatment of cornea flap folds and striae after laser in situ keratomileusis (LASIK).To review the management and results of cases with severe flap wrinkling or dislodgment after LASIK.Methods Eleven patients with cornea flap folds and striae after LASIK are described.To make retrospective analysis of etiology and treatment in 11 cases who had cornea flap folds and striae after LASIK.Surgical repositioning of the flap was performed in all cases.Under the operating microscope the flap was refloated and hydrated with sterile deionized water for 2 minutes without stretching or ironing the flap.A bandage contact lens was then applied for 24 hours.Flap status,refractive changes,and final uncorrected and best corrected visual acuities were used to evaluate the outcome of flap repositioning.Results Relocation flap and bandage contact lens were used in such cases.Scraping epithelial and hydrating the cornea flap with sterile deionized water were used under operation.Twenty-four hours after treatment with sterile deionized water and a bandage contact lens,the cornea was smooth and wrinkle free.All patients

  20. Microbiota bacteriana aeróbia da conjuntiva de doadores de córnea Aerobic bacterial microbiota of the conjunctiva of cornea donors

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    Paula Fontana Lorenzini

    2007-03-01

    Full Text Available OBJETIVOS: Determinar a microbiota bacteriana aeróbia da conjuntiva de doadores de córnea e seu padrão de suscetibilidade a antibióticos; verificar o número de córneas utilizadas para transplante e a média de tempo de preservação em solução preservante com gentamicina e estreptomicina; traçar o perfil dos doadores e receptores de córnea. MÉTODOS: Espécimes clínicos foram colhidos de saco inferior da conjuntiva de ambos os olhos, de 40 doadores de córnea. As amostras foram inoculadas em ágar sangue azida, ágar chocolate e ágar MacConkey e o antibiograma foi realizado pelo método de Kirby-Bauer. RESULTADOS: A freqüência de cultura positiva da conjuntiva de doadores de córnea foi de 72,5%, sendo que Gram-positivos totalizaram 81,6% e apenas 18,4% das amostras foram identificadas como Gram-negativos. Vancomicina inibiu 100% dos Gram-positivos, ao passo que a sensibilidade dos Gram-negativos à gentamicina foi de 53,8% e à estreptomicina foi de 30%. O sexo masculino predominou entre os doadores e receptores, a média de tempo entre o óbito e a enucleação foi de 2h e a de preservação em solução preservante com gentamicina e estreptomicina foi de 7 dias. Neoplasia e mais de uma causa associada foram as causas de óbito mais freqüentes. O ceratocone foi a principal indicação para transplante (51,7%. CONCLUSÕES: Staphylococcus coagulase negativo foi o microrganismo com o maior número de isolamentos, apresentando sensibilidade variada aos antimicrobianos. A quantidade de córneas utilizadas para transplante foi bastante inferior em relação ao total de captações. O perfil dos doadores e receptores de córnea mostrou-se heterogêneo para grande parte das variáveis analisadas.PURPOSE: To determine aerobic bacterial microbiota of the conjunctiva of cornea donors and its patterns of susceptibility to antibiotics; verify the number of corneas used for transplant and the average time of preservation in solutions with

  1. Microscopia confocal en córneas de cien ojos sanos Confocal microscopy results of one hundred healthy eye corneas

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    Zulema Gómez Castillo

    2012-06-01

    Full Text Available Objetivo: Analizar las estructuras celulares por microscopia confocal, Confoscan 4, en córneas sanas en nuestro medio. Métodos: Se realizó un estudio prospectivo longitudinal a 100 ojos sanos de médicos que trabajan en nuestra institución, y pacientes que asistieron al servicio de córnea. Esta investigación fue desde mayo de 2007 a mayo 2008, en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer", La Habana. En los médicos se examinaron ambos ojos y en los pacientes el ojo no afectado. Se recopilaron un total de 50 casos sin afección corneal. Resultados: De los 100 ojos estudiados, 64 tenían paquimetrías por encima del valor medio. Estuvieron presentes los tres tipos de células epiteliales en casi la totalidad de los pacientes; así como los queratocitos en las diferentes profundidades del estroma corneal. La mayoría de los ojos tenían un conteo celular endotelial por encima de 2 500, cifra comprendida dentro de los valores normales. Se encontraron fibras nerviosas en cada una de sus capas. Conclusiones: La microscopia confocal se presenta como una nueva herramienta que permite observar en vivo la histología corneal y complementar las observaciones de la biomicroscopia convencional. Esto constituye un reto para el mejor entendimiento de la histopatología corneal. De esta manera podemos actuar de forma profiláctica y terapéutica, en el seguimiento y evolución de patologías corneales.Objective: This paper is aimed at analyzing the corneal cellular structures through Confoscan S4-aided confocal microscopy in apparently healthy corneas. Methods: A prospective longitudinal study of 100 healthy eyes from practicing doctors, and from patients who had attended the corneal service at “Ramón Pando Ferrer” Cuban Institute of Ophthalmology in Havana since May 2007 was conducted. Both eyes of participating doctors were examined whereas the non-affected eye was examined in the patients. A total of 50 cases with no corneal

  2. Evaluation of the HB&L System for the Microbiological Screening of Storage Medium for Organ-Cultured Corneas

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    D. Camposampiero

    2013-01-01

    Full Text Available Aims. To compare HB&L and BACTEC systems for detecting the microorganisms contaminating the corneal storage liquid preserved at 31°C. Methods. Human donor corneas were stored at 4°C followed by preservation at 31°C. Samples of the storage medium were inoculated in BACTEC Peds Plus/F (aerobic microorganisms, BACTEC Plus Anaerobic/F (anaerobic microorganisms, and HB&L bottles. The tests were performed (a after six days of storage, (b end of storage, and (c after 24 hours of preservation in deturgescent liquid sequentially. 10,655 storage and deturgescent media samples were subjected to microbiological control using BACTEC (6-day incubation and HB&L (24-hour incubation systems simultaneously. BACTEC positive/negative refers to both/either aerobic and anaerobic positives/negatives, whereas HB&L can only detect the aerobic microbes, and therefore the positives/negatives depend on the presence/absence of aerobic microorganisms. Results. 147 (1.38% samples were identified positive with at least one of the two methods. 127 samples (134 identified microorganisms were positive with both HB&L and BACTEC. 14 HB&L+/BACTEC− and 6 BACTEC+/HB&L− were identified. Sensitivity (95.5%, specificity (99.8%, and positive (90.1% and negative predictive values (99.9% were high with HB&L considering a 3.5% annual contamination rate. Conclusion. HB&L is a rapid system for detecting microorganisms in corneal storage medium in addition to the existing methods.

  3. 真菌毒素与角膜真菌感染%Mycotoxins and fungal infection of cornea

    Institute of Scientific and Technical Information of China (English)

    吴福进; 胡建章; 韩晓丽

    2013-01-01

    Mycotoxins are secondary metabolites produced by the toxigenic fungi in suitable environmental conditions,the main toxicity of which are carcinogenesis,genotoxicity,teratogenesis,hepatotoxicity and immunosuppression.After fungal infects the cornea,it may release mycotoxins to cause corneal damage.However what roles do the mycotoxins play in fungal keratitis is still unclear.The biosynthesis of mycotoxinis is regulated by a series of related function genes ; in addition,pH value,carbon nitrogen ratio and other environmental conditions are the influence factors as well.This article reviews the common harms,regulatory factors and their possible roles in the occurrence and development of keratomycosis.%真菌毒素(Mycotoxin)是由产毒真菌在适宜的环境条件下产生的具有毒性的次级代谢产物,主要毒性有致癌作用、遗传毒性、致畸作用、肝细胞毒性和免疫抑制等.真菌感染角膜后可能释放真菌毒素导致角膜损害,但至今对真菌毒素在真菌性角膜炎中究竟扮演什么角色,仍不明确.真菌毒素的生物合成受到一系列相关功能基因的调控;此外,pH值、碳氮比等环境条件也能影响其产量.本文就常见的真菌毒素的危害、调控因素及其可能在真菌性角膜炎发生发展中的作用进行综述.

  4. Mechanisms involved in the anti-inflammatory action of a polysulfated fraction from Gracilaria cornea in rats.

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    Chistiane Oliveira Coura

    Full Text Available The anti-inflammatory mechanisms of the sulfated polysaccharidic fraction obtained from red marine alga Gracilaria cornea (Gc-FI were investigated using a paw edema model induced in rats by different inflammatory agents (carrageenan, dextran, serotonin, bradykinin, compound 48/80 or L-arginine. Gc-FI at the doses of 3, 9 or 27 mg/kg, subcutaneously--s.c., significantly inhibited rat paw edema induced by carrageenan and dextran, as confirmed by myeloperoxidase and Evans' blue assessments, respectively. Gc-FI (9 mg/kg, s.c. inhibited rat paw edema induced by histamine, compound 48/80 and L-arginine. Additionally, Gc-FI (9 mg/kg, s.c. inhibited Cg-induced edema in animals with intact mast cells but did not inhibit that with degranulated mast cells by compound 48/80, revealing a protective role on mast cell membranes. Gc-FI down-regulated the IL-1β, TNF-α and COX-2 mRNA and protein levels compared with those of the carrageenan group, based on qRT-PCR and immunohistochemistry analyses. After inhibition with ZnPP IX, a specific heme oxygenase-1 (HO-1 inhibitor, the anti-inflammatory effect of Gc-FI was not observed in Cg-induced paw edema, suggesting that the anti-inflammatory effect of Gc-FI is, in part, dependent on the integrity of the HO-1 pathway. Gc-FI can target a combination of multiple points involved in inflammatory phenomena.

  5. Mechanisms involved in the anti-inflammatory action of a polysulfated fraction from Gracilaria cornea in rats.

    Science.gov (United States)

    Coura, Chistiane Oliveira; Souza, Ricardo Basto; Rodrigues, José Ariévilo Gurgel; Vanderlei, Edfranck de Sousa Oliveira; de Araújo, Ianna Wivianne Fernandes; Ribeiro, Natássia Albuquerque; Frota, Annyta Fernandes; Ribeiro, Kátia Alves; Chaves, Hellíada Vasconcelos; Pereira, Karuza Maria Alves; da Cunha, Rodrigo Maranguape Silva; Bezerra, Mirna Marques; Benevides, Norma Maria Barros

    2015-01-01

    The anti-inflammatory mechanisms of the sulfated polysaccharidic fraction obtained from red marine alga Gracilaria cornea (Gc-FI) were investigated using a paw edema model induced in rats by different inflammatory agents (carrageenan, dextran, serotonin, bradykinin, compound 48/80 or L-arginine). Gc-FI at the doses of 3, 9 or 27 mg/kg, subcutaneously--s.c., significantly inhibited rat paw edema induced by carrageenan and dextran, as confirmed by myeloperoxidase and Evans' blue assessments, respectively. Gc-FI (9 mg/kg, s.c.) inhibited rat paw edema induced by histamine, compound 48/80 and L-arginine. Additionally, Gc-FI (9 mg/kg, s.c.) inhibited Cg-induced edema in animals with intact mast cells but did not inhibit that with degranulated mast cells by compound 48/80, revealing a protective role on mast cell membranes. Gc-FI down-regulated the IL-1β, TNF-α and COX-2 mRNA and protein levels compared with those of the carrageenan group, based on qRT-PCR and immunohistochemistry analyses. After inhibition with ZnPP IX, a specific heme oxygenase-1 (HO-1) inhibitor, the anti-inflammatory effect of Gc-FI was not observed in Cg-induced paw edema, suggesting that the anti-inflammatory effect of Gc-FI is, in part, dependent on the integrity of the HO-1 pathway. Gc-FI can target a combination of multiple points involved in inflammatory phenomena.

  6. A histological study of rabbit corneas after transepithelial corneal crosslinking using partial epithelial photoablation or ethanol treatment

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    Mehmet Cuneyt Ozmen

    2014-12-01

    Full Text Available AIM: To evaluate the histological changes after transepithelial corneal crosslinking (CXL using partial thickness excimer laser ablation or epithelial ethanol application in an experimental rabbit study.METHODS: Right eyes of twenty-four rabbits were studied. Four eyes received total epithelial debridement (group I. Four eyes received partial thickness epithelial ablation with excimer laser (group II. Twelve eyes were treated with different durations (30s and 60s and concentrations (18% to 48% of ethanol (group III. Riboflavin was applied for 30min intervals along with topical proparacaine drops with benzalkonium chloride, and 370 nm irradiation was performed for 30min, while riboflavin was instilled every 3min. Four eyes (group IV received 48% ethanol for 30s without riboflavin and irradiation. Eyes were collected after 24h and examined histologically.RESULTS: All eyes in group I showed keratocyte loss in the superficial 300 µ of corneal storma. In group II, 1-4 layers of epithelium were preserved and no keratocyte loss occurred. In group III, CXL after treatment with ethanol up to 24% concentration and up to 60s revealed no keratocyte loss. CXL after treatment with 48% and higher ethanol concentrations yielded keratocyte loss in the superficial 200 µ to 300 µ of cornea.CONCLUSION: Incomplete excimer laser ablation of the epithelium or treatment with ethanol up to 24% concentration and up to 60s duration yielded no stromal keratocyte loss. To get the same histological appearance seen in epithelial debridement group, partial thickness excimer laser epithelial ablation or ethanol application is not adequate for transepithelial CXL.

  7. Effect of Biometric Characteristics on the Change of Biomechanical Properties of the Human Cornea due to Cataract Surgery

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    Xuefei Song

    2014-01-01

    Full Text Available Purpose. To determine the impact of biometric characteristics on changes of biomechanical properties of the human cornea due to standard cataract surgery using biomechanical analysis. Patients and Methods. This prospective consecutive cross-sectional study comprised 54 eyes with cataract in stages I or II that underwent phacoemulsification and IOL implantation. CH, CRF, IOPg, and IOPcc intraocular pressure were measured by biomechanical analysis preoperatively and at 1 month postoperatively. Changes (Δ were calculated as preoperative value versus postoperative value. Biometrical data were extracted from TMS-5 (CSI and SAI, IOLMaster (AL, and EM-3000 (CCT and ECC preoperatively. Results. The average values of the changes were ΔCH=-0.45±1.27 mmHg, ΔCRF=-0.88±1.1 mmHg, ΔIOPg=-1.58±3.15 mmHg, and ΔIOPcc=-1.45±3.93 mmHg. The higher the CSI the smaller the decrease in CH (r=0.302, P=0.028. The higher the CCT the larger the decrease in CRF (r=-0.371, P=0.013. The higher the AL the smaller the decrease in IOPg (r=0.417, P=0.005. The higher the AL, SAI, and EEC the smaller the decrease in IOPcc (r=0.351, P=0.001; r=-0.478, P<0.001; r=0.339, P=0.013. Conclusions. Corneal biomechanical properties were affected by comprehensive factors after cataract surgery, including corneal endothelium properties, biometry, and geometrical characteristics.

  8. Evaluation of the HB&L System for the Microbiological Screening of Storage Medium for Organ-Cultured Corneas.

    Science.gov (United States)

    Camposampiero, D; Grandesso, S; Zanetti, E; Mazzucato, S; Solinas, M; Parekh, M; Frigo, A C; Gion, M; Ponzin, D

    2013-01-01

    Aims. To compare HB&L and BACTEC systems for detecting the microorganisms contaminating the corneal storage liquid preserved at 31°C. Methods. Human donor corneas were stored at 4°C followed by preservation at 31°C. Samples of the storage medium were inoculated in BACTEC Peds Plus/F (aerobic microorganisms), BACTEC Plus Anaerobic/F (anaerobic microorganisms), and HB&L bottles. The tests were performed (a) after six days of storage, (b) end of storage, and (c) after 24 hours of preservation in deturgescent liquid sequentially. 10,655 storage and deturgescent media samples were subjected to microbiological control using BACTEC (6-day incubation) and HB&L (24-hour incubation) systems simultaneously. BACTEC positive/negative refers to both/either aerobic and anaerobic positives/negatives, whereas HB&L can only detect the aerobic microbes, and therefore the positives/negatives depend on the presence/absence of aerobic microorganisms. Results. 147 (1.38%) samples were identified positive with at least one of the two methods. 127 samples (134 identified microorganisms) were positive with both HB&L and BACTEC. 14 HB&L+/BACTEC- and 6 BACTEC+/HB&L- were identified. Sensitivity (95.5%), specificity (99.8%), and positive (90.1%) and negative predictive values (99.9%) were high with HB&L considering a 3.5% annual contamination rate. Conclusion. HB&L is a rapid system for detecting microorganisms in corneal storage medium in addition to the existing methods.

  9. 5-Fluorouracil for the treatment of intraepithelial neoplasia and squamous cell carcinoma of the conjunctiva, and cornea

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    Abdulmoghni Al-Barrag

    2010-07-01

    Full Text Available Abdulmoghni Al-Barrag1, Mutahar Al-Shaer1, Nabil Al-Matary2, Mohammed Al-Hamdani21Ophthalmic Department, Faculty of Medicine and Health Sciences, Sana’a University, Sana’a, Republic of Yemen; 2Ophthalmic Department, Military Hospital, Sana’a, Republic of YemenObjective: To evaluate the efficacy and risks of complications of pulse dosing of topical 5-fluorouracil (5-FU in the treatment of corneal intraepithelial neoplasia (CIN, and conjunctival squamous cell carcinoma (SCC. Design: Prospective, noncomparative case series. Participants: Fifteen patients with histological evidence CIN or SCC of the conjunctiva and cornea were identified by tumor biopsy. Methods: All patients clinically evident of CIN, or SCC were evaluated, with maximum 30 months of follow-up were treated with pulsed dosing of 1% 5-FU. Treatment cycles were defined as four times per day for 4 days using the medication followed by 30 days without medication. The number of initial treatment was six cycles. Results: The mean age of the 15 patients was 50.8 years (range 25–78 years. Excision biopsy proved seven cases as CIN, and eight cases as locally invasive SCC. All patients remained disease free with a mean follow-up of 14.53 months (range 6-30 months. Additional chemotherapy was given after the initial treatment cycles, only for one case. 5-FU caused mild temporary local irritation, but no long-term intraocular or extra ocular complications. Conclusions: Adjuvant 1% topical 5-FU appears to be effective in the prevention of recurrence of conjunctival or corneal CIN and SCC after excision biopsy. Our results indicate that at least six cycles of topical 1% 5-FU is required to prevent local recurrence in the long term. It is well-tolerated and an effective method of treatment. No complications that would preclude use of our dose regimen were noted.Keywords: chemotherapy, fluorouracil, neoplasia, treatment cycles

  10. Microbiota bacteriana da conjuntiva de doadores de córnea Bacterial microbiota of the conjunctiva of donor corneas

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    Maria Emília Xavier dos Santos Araújo

    2004-12-01

    Full Text Available OBJETIVOS: Quantificar e qualificar a microbiota aeróbia da conjuntiva de doadores de córnea segundo a interferência do intervalo de tempo entre o óbito e a colheita do espécime conjuntival, a causa do óbito e a idade do doador e avaliar a atividade biocida de determinados antibióticos aos microrganismos isolados. MÉTODOS: Entre janeiro e março de 1994 foram colhidos espécimes da conjuntiva de 242 olhos de doadores de córnea. O material transportado em meio de Stuart foi semeado em ágares sangue, chocolate, sangue azida, MacConkey e caldo tioglicolato. Foi registrada a idade do doador, hora e causa do óbito. A atividade biocida dos antibióticos foi avaliada pela metodologia de Kirby e Bauer. A análise estatística utilizou os testes do qui-quadrado, exato de Fisher e Mann-Whitney. RESULTADOS: A freqüência de cultura positiva da conjuntiva de doadores de córnea foi de 91,7%. A mediana da idade dos doadores foi de 62 anos e do intervalo de tempo entre o óbito e a colheita do espécime foi de 4,2 horas. A causa mais freqüente de óbito foi doença cardiovascular (26,4%. Não houve diferença significante entre a cultura positiva e as variáveis estudadas. A vancomicina inibiu 100% das cepas de bactérias Gram-positivas e a sensibilidade dos bacilos Gram-negativos à gentamicina variou de 36,7% a 92,3%. CONCLUSÕES: O estudo revelou freqüência elevada de cultura positiva da conjuntiva de doadores de córneas. Staphylococcus coagulase negativo foi a espécie com maior número de isolamentos positivos. Não foi encontrada associação entre os fatores de risco avaliados e cultura positiva. Os antibióticos tiveram atividade biocida variável sobre os Gram-negativos e 100% dos Gram-positivos foram sensíveis à vancomicina.PURPOSE: To identify and qualify bacterial organisms in conjunctival tissue of donor corneas. To correlate the frequency of positive cultures with donor age, cause of death, and time from death to collection of

  11. Reduced expression of Pax6 in lens and cornea of mutant mice leads to failure of chamber angle development and juvenile glaucoma.

    Science.gov (United States)

    Kroeber, Markus; Davis, Noa; Holzmann, Silvia; Kritzenberger, Michaela; Shelah-Goraly, Michal; Ofri, Ron; Ashery-Padan, Ruth; Tamm, Ernst R

    2010-09-01

    Heterozygous mutations in PAX6 are causative for aniridia, a condition that is frequently associated with juvenile glaucoma. Defects in morphogenesis of the iridocorneal angle, such as lack of trabecular meshwork differentiation, absence of Schlemm's canal and blockage of the angle by iris tissue, have been described as likely causes for glaucoma, and comparable defects have been observed in heterozygous Pax6-deficient mice. Here, we employed Cre/loxP-mediated inactivation of a single Pax6 allele in either the lens/cornea or the distal optic cup to dissect in which tissues both alleles of Pax6 need to be expressed to control the development of the tissues in the iridocorneal angle. Somatic inactivation of one allele of Pax6 exclusively from epithelial cells of lens and cornea resulted in the disruption of trabecular meshwork and Schlemm's canal development as well as in an adhesion between iris periphery and cornea in juvenile eyes, which resulted in the complete closure of the iridocorneal angle in the adult eye. Structural changes in the iridocorneal angle presumably caused a continuous increase in intraocular pressure leading to degenerative changes in optic nerve axons and to glaucoma. In contrast, the inactivation of a single Pax6 allele in the distal optic cup did not cause obvious changes in iridocorneal angle formation. We conclude that the defects in iridocorneal angle formation are caused by non-autonomous mechanisms due to Pax6 haploinsufficiency in lens or corneal epithelial cells. Pax6 probably controls the expression of signaling molecules in lens cells that regulate the morphogenetic processes during iridocorneal angle formation.

  12. Boston type I keratoprosthesis-donor cornea interface evaluated by high-definition spectral-domain anterior segment optical coherence tomography.

    Science.gov (United States)

    Fernandez, Ana G Alzaga; Radcliffe, Nathan M; Sippel, Kimberly C; Rosenblatt, Mark I; Sood, Priyanka; Starr, Christopher E; Ciralsky, Jessica B; D'Amico, Donald J; Kiss, Szilárd

    2012-01-01

    The purpose of this study was to assess whether the resolution offered by two different, recently commercially available high-resolution, spectral-domain anterior segment optical coherence tomography (AS-OCT) instruments allows for detailed anatomic characterization of the critical device-donor cornea interface in eyes implanted with the Boston type I permanent keratoprosthesis. Eighteen eyes of 17 patients implanted with the Boston type I keratoprosthesis were included in this retrospective case series. All eyes were quantitatively evaluated using the Cirrus HD-OCT while a subset (five eyes) was also qualitatively imaged using the Spectralis Anterior Segment Module. Images from these instruments were analyzed for evidence of epithelial migration onto the anterior surface of the keratoprosthesis front plate, and presence of a vertical gap between the posterior surface of the front plate and the underlying carrier donor corneal tissue. Quantitative data was obtained utilizing the caliper function on the Cirrus HD-OCT. The mean duration between AS-OCT imaging and keratoprosthesis placement was 29 months. As assessed by the Cirrus HD-OCT, 83% of eyes exhibited epithelial migration over the edge of the front plate. Fifty-six percent of the keratoprosthesis devices displayed good apposition of the device with the carrier corneal donor tissue. When a vertical gap was present (44% of eyes), the mean gap was 40 (range 8-104) microns. The Spectralis Anterior Segment Module also displayed sufficient resolution to allow for similar characterization of the device-donor cornea interface. Spectral-domain AS-OCT permits high resolution imaging of the keratoprosthesis device-donor cornea interface. Both the Cirrus HD-OCT and the Spectralis Anterior Segment module allowed for visualization of epithelial coverage of the device-donor cornea interface, as well as identification of physical gaps. These imaging modalities, by yielding information in regard to integration of the

  13. Introduction of quantitative and qualitative cornea optical coherence tomography findings induced by collagen cross-linking for keratoconus: a novel effect measurement benchmark

    Directory of Open Access Journals (Sweden)

    Kanellopoulos AJ

    2013-02-01

    Full Text Available A John Kanellopoulos1,2 George Asimellis11Laservision.gr Institute, Athens, Greece; 2New York University Medical School, New York, NY, USAPurpose: To introduce a novel, noninvasive technique to determine the depth and extent of anterior corneal stroma changes induced by collagen cross-linking (CXL using quantitative analysis of high-resolution anterior-segment optical coherence tomography (OCT post-operative images.Setting: Private clinical ophthalmology practice.Patients and methods: Two groups of corneal cross-sectional images obtained with the OptoVue RTVue anterior-segment OCT system were studied: group A (control consisted of unoperated, healthy corneas, with the exception of possible refractive errors. The second group consisted of keratoconic corneas with CXL that were previously operated on. The two groups were investigated for possible quantitative evidence of changes induced by the CXL, and specifically, the depth, horizontal extent, as well as the cross-sectional area of intrastromal hyper-reflective areas (defined in our study as the area consisting of pixels with luminosity greater than the mean +2 × standard deviation of the entire stromal cross section within the corneal stroma.Results: In all images of the second group (keratoconus patients treated with CXL there was evidence of intrastromal hyper-reflective areas. The hyper-reflective areas ranged from 0.2% to 8.8% of the cross-sectional area (mean ± standard deviation; 3.46% ± 1.92%. The extent of the horizontal hyper-reflective area ranged from 4.42% to 99.2% (56.2% ± 23.35% of the cornea image, while the axial extent (the vertical extent in the image ranged from 40.00% to 86.67% (70.98% ± 7.85%. There was significant statistical difference (P < 0.02 in these values compared to the control group, in which, by application of the same criteria, the same hyper-reflective area (owing to signal noise ranged from 0.00% to 2.51% (0.74% ± 0.63%.Conclusion: Herein, we introduce a

  14. Conhecimento de estudantes de medicina sobre o processo de doação de córneas The knowledge of medical students about cornea donation

    Directory of Open Access Journals (Sweden)

    Rodrigo França de Espíndola

    2007-08-01

    Full Text Available OBJETIVO: Avaliar o conhecimento de estudantes de medicina sobre o processo de doação de córneas, comparando-o entre aqueles que já cursaram a disciplina de Oftalmologia com os demais. MÉTODOS: Foi aplicado um questionário a estudantes de medicina do interior de São Paulo, contendo dados como: idade, sexo, ano de graduação e 10 perguntas de múltipla escolha sobre o tema. As questões abordaram o limite de idade para doação, contra-indicações para o transplante, tempo para retirada das córneas, dentre outras. Foi comparado o conhecimento (% de acertos entre aqueles que haviam cursado a disciplina de Oftalmologia (Grupo A com os demais (Grupo B. RESULTADOS: Foram entrevistados 402 estudantes. Destes, 140 eram do grupo A e 262 do grupo B. Não houve diferença estatisticamente significante entre os dois grupos (p=0,8328. CONCLUSÃO: O conhecimento sobre o processo de doação de córneas mostrou-se insuficiente entre os alunos entrevistados, mesmo para aqueles que haviam cursado a disciplina de Oftalmologia, apontando a necessidade de aperfeiçoamento do conhecimento divulgado nas escolas médicas.PURPOSE: To compare knowledge of medical students about the cornea donation process among those who already studied Ophthalmology and the others. METHODOS: A questionnaire containing data as: age, sex, graduation year, and 10 multiple-choice questions about the subject was applied to medical students from the interior of São Paulo state, Brazil. The questions were: age for donation, contraindication for transplants, the time limit to remove the cornea, among others. The knowledge regarding cornea donation was compared between the two groups: students who already studied Ophthalmology (Group A and the others (Group B. RESULTS: The study group was composed of 402 students, of whom 140 were of group A and 262 of group B. Knowledge between the two groups was different, but not statistically significant (p=0.8328. CONCLUSION: Knowledge about

  15. Boston type I keratoprosthesis-donor cornea interface evaluated by high-definition spectral-domain anterior segment optical coherence tomography

    Directory of Open Access Journals (Sweden)

    Alzaga Fernandez AG

    2012-08-01

    Full Text Available Ana G Alzaga Fernandez,* Nathan M Radcliffe,* Kimberly C Sippel, Mark I Rosenblatt, Priyanka Sood, Christopher E Starr, Jessica B Ciralsky, Donald J D'Amico, Szilárd KissDepartment of Ophthalmology, Weill Cornell Medical College, New York-Presbyterian Hospital, New York, NY, USA*These authors contributed equally to this work and both are considered principal authorsBackground: The purpose of this study was to assess whether the resolution offered by two different, recently commercially available high-resolution, spectral-domain anterior segment optical coherence tomography (AS-OCT instruments allows for detailed anatomic characterization of the critical device-donor cornea interface in eyes implanted with the Boston type I permanent keratoprosthesis.Methods: Eighteen eyes of 17 patients implanted with the Boston type I keratoprosthesis were included in this retrospective case series. All eyes were quantitatively evaluated using the Cirrus HD-OCT while a subset (five eyes was also qualitatively imaged using the Spectralis Anterior Segment Module. Images from these instruments were analyzed for evidence of epithelial migration onto the anterior surface of the keratoprosthesis front plate, and presence of a vertical gap between the posterior surface of the front plate and the underlying carrier donor corneal tissue. Quantitative data was obtained utilizing the caliper function on the Cirrus HD-OCT.Results: The mean duration between AS-OCT imaging and keratoprosthesis placement was 29 months. As assessed by the Cirrus HD-OCT, 83% of eyes exhibited epithelial migration over the edge of the front plate. Fifty-six percent of the keratoprosthesis devices displayed good apposition of the device with the carrier corneal donor tissue. When a vertical gap was present (44% of eyes, the mean gap was 40 (range 8–104 microns. The Spectralis Anterior Segment Module also displayed sufficient resolution to allow for similar characterization of the device

  16. [Cornea in diabetus mellitus].

    Science.gov (United States)

    Simion, Maria; Selaru, Daniela

    2011-01-01

    Diabetus mellitus is associated with numerous ocular complications. Diabetic keratopathy occurs in response to a neuropathy of the ophthalmic division of the trigeminal nerve, but also as a result of epithelial subclinical abnormalities, limbal vasculopathy and decrease in tear production. It comprises several symptomatic corneal conditions inducing superficial punctate keratopathy and persistent corneal epithelial erosions; the latter can progress to corneal ulceration and is often resistant to routine clinical management.

  17. CORNEA AND ANTERIOR SEGMENT

    African Journals Online (AJOL)

    A Comparison of Visual Outcomes after Extracapsular Cataract. Surgery and ... 07-0007;. 2007. p. iv. Available from: http://www.archive.ahrq.gov/data/hcup/ ... Case Report: An 11-year-old pupil presented with two days history of pain, redness ...

  18. Biofiltration of fishpond effluents and accumulation of N-compounds (phycobiliproteins and mycosporine-like amino acids) versus C-compounds (polysaccharides) in Hydropuntia cornea (Rhodophyta).

    Science.gov (United States)

    Figueroa, Félix L; Korbee, Nathalie; Abdala, Roberto; Jerez, Celia G; López-de la Torre, Mayra; Güenaga, Leire; Larrubia, María A; Gómez-Pinchetti, Juan L

    2012-02-01

    The biofiltration capacity, biomass-yield and accumulation of N- and C-compounds of Hydropuntia cornea were analyzed. Algae were grown in different conditions for 28 d: outdoor and indoor, with or without fishpond effluents. N-uptake efficiency of these effluents was higher than 95% after 7 d both outdoors and indoors. N-enriched conditions reduced the extent of photoinhibition and increased the maximal quantum yield in H. cornea. The biomass-yield was higher in outdoor grown-algae after 7 d and decreased independently of the treatment after 28 d. N, acid polysaccharide (AP) and mycosporine-like amino acid (MAA)-yields decreased throughout the experiment in all conditions. The highest MAA-yield was observed in fishpond effluent outdoor-grown algae, indicating a positive effect of increased radiation on MAA accumulation. However, APs were higher under N-depleted conditions. The use of MAAs as UV-screening and antioxidants, and the use of AP as immunostimulants are discussed.

  19. A comparative clinical study of Solcoseryl Eye-Gel and Cysteine Eye-Gel 2.4% in the treatment of foreign-body injuries of the cornea.

    Science.gov (United States)

    Studer, O

    1984-01-01

    Solcoseryl, a protein-free haemodialysate, promotes tissue regeneration and improves utilization of oxygen in the cell. In a randomized, double-blind, clinical study, Solcoseryl Eye-Gel was compared with Cysteine Eye-Gel in the treatment of foreign-body injuries of the cornea in a total of 99 eyes. In order to facilitate objective evaluation of the effects of the treatment, the area of the lesion before the start of treatment and on the following day was determined by means of slit-lamp photographs. Healing of the lesion and relative reduction of the area of the wound were observed much more frequently in the group treated with Solcoseryl Eye-Gel than in the reference group. Maculae corneae after the end of the treatment were significantly less frequent under Solcoseryl Eye-Gel than under Cysteine Eye-Gel. Teh tolerability of the test preparation was good; an itching sensation was reported in only 2 cases. Under Cysteine Eye-Gel, on the other hand, a burning sensation was reported by a number of patients and very fine deposits in the epithelium were also observed in a few cases. Thus complete closure of the epithelium over the lesion after 1 day was observed much more frequently in the group of patients treated with Solcoseryl Eye-Gel than in the reference group (63 vs. 53%).

  20. Corneal Melting after Collagen Cross-Linking for Keratoconus in a Thin Cornea of a Diabetic Patient Treated with Topical Nepafenac: A Case Report with a Literature Review

    Directory of Open Access Journals (Sweden)

    Karim Mohamed-Noriega

    2016-02-01

    Full Text Available Purpose: To report the case of a 50-year-old woman with diabetes that presented with corneal melting and perforation 6 weeks after collagen cross-linking (CxL for keratoconus (KC and postoperative use of nepafenac eye drops, a nonsteroidal anti-inflammatory drug (NSAID. Methods: This is a case report of a patient with diabetes, KC and a thin cornea that had undergone left eye corneal CxL at a different hospital followed by postoperative use of nepafenac eye drops for 6 weeks. Results: The patient presented for the first time to our clinic with left corneal melting, perforation and iris prolapse 6 weeks after corneal CxL and topical nepafenac use. She was treated with a left eye tectonic penetrating keratoplasty, extracapsular cataract extraction, intraocular lens implantation and pupilloplasty. Conclusions: The corneal melting and perforation in this patient was associated with multiple risk factors: (1 nepafenac eye drop use, (2 CxL in a cornea thinner than 400 µm and (3 diabetes. The recommended corneal thickness limits should be respected. Topical NSAIDs should be used with caution if used as postoperative treatment after corneal CxL and in patients with diabetes, epithelial defect or delayed healing, because of the possible increased risk for corneal melting when multiple risk factors are observed.

  1. Long-Term Cultures of Human Cornea Limbal Explants Form 3D Structures Ex Vivo - Implications for Tissue Engineering and Clinical Applications.

    Science.gov (United States)

    Szabó, Dóra Júlia; Noer, Agate; Nagymihály, Richárd; Josifovska, Natasha; Andjelic, Sofija; Veréb, Zoltán; Facskó, Andrea; Moe, Morten C; Petrovski, Goran

    2015-01-01

    Long-term cultures of cornea limbal epithelial stem cells (LESCs) were developed and characterized for future tissue engineering and clinical applications. The limbal tissue explants were cultivated and expanded for more than 3 months in medium containing serum as the only growth supplement and without use of scaffolds. Viable 3D cell outgrowth from the explants was observed within 4 weeks of cultivation. The outgrowing cells were examined by immunofluorescent staining for putative markers of stemness (ABCG2, CK15, CK19 and Vimentin), proliferation (p63α, Ki-67), limbal basal epithelial cells (CK8/18) and differentiated cornea epithelial cells (CK3 and CK12). Morphological and immunostaining analyses revealed that long-term culturing can form stratified 3D tissue layers with a clear extracellular matrix deposition and organization (collagen I, IV and V). The LESCs showed robust expression of p63α, ABCG2, and their surface marker fingerprint (CD117/c-kit, CXCR4, CD146/MCAM, CD166/ALCAM) changed over time compared to short-term LESC cultures. Overall, we provide a model for generating stem cell-rich, long-standing 3D cultures from LESCs which can be used for further research purposes and clinical transplantation.

  2. Commercially available rigid gas-permeable contact lens for protecting the cornea from drying during vitrectomy with a wide viewing system

    Directory of Open Access Journals (Sweden)

    Kamei M

    2012-08-01

    Full Text Available Motohiro Kamei, Nagakazu Matsumura, Hirokazu Sakaguchi, Yusuke Oshima, Yasushi Ikuno, Kohji NishidaDepartment of Ophthalmology, Osaka University Graduate School of Medicine, Osaka, JapanPurpose: We evaluated the usefulness of commercially available materials for protecting the cornea from drying during vitrectomy with a wide-angle viewing system.Methods: Three vitreoretinal surgeons evaluated fundus visibility during vitrectomy on the images of five study materials used on the cornea: balanced saline solution, a viscoelastic agent, a vitrectomy contact lens, a rigid gas permeable (RGP contact lens, and a soft contact lens. Fundus visibility was graded using the following scale: grade 1, unclear; grade 2, slightly unclear; grade 3, clear; and grade 4, very clear.Results: Respective scores for each material used during core vitrectomy and membrane removal were: balanced saline solution, 3.3/3.3; viscoelastic agent, 3.8/3.3; vitrectomy contact lens, 3.3/4.0; RGP contact lens, 4.0/3.9; soft contact lens, 1.1/not applicable.Conclusion: The RGP contact lens provided visibility similar to or clearer than that obtained with other methods. Because of its ease of use and lower cost, use of the RGP contact lens is ideal during vitrectomy performed with a wide-angle viewing system.Keywords: contact lens, RGP, viscoelastic agent, vitrectomy, wide viewing system

  3. Research progress of correction of cornea astigmatism after cataract extraction%白内障术后角膜散光矫正的研究进展

    Institute of Scientific and Technical Information of China (English)

    杨宁

    2012-01-01

    随着白内障手术由复明手术向屈光手术的转变,角膜散光已成为影响白内障术后裸眼视力的主要因素之一.矫正术前存在的角膜散光,控制手术源性散光,是解决白内障术后因散光导致的术后视力不佳的有效方法.本文将对控制和矫正白内障术后散光的治疗进展进行综述.%Cataract operation has evolved from pure vision improvement toward the optics for reducing refractive errors. The main factor affecting naked vision of postoperative cataract surgery is cornea astigmatism . To correct cornea astigmatism and decrease surgically induced astigmatism are required for resolving problems of post cataract operative refraction and improving visual acuity. The research progress of reducing and correcting astigmatism after cataract extraction was summarized in this paper.

  4. Corneal Cross-Linking with Riboflavin and UV-A in the Mouse Cornea in Vivo: Morphological, Biochemical, and Physiological Analysis

    Science.gov (United States)

    Kling, Sabine; Hammer, Arthur; Conti, Alain; Hafezi, Farhad

    2017-01-01

    Purpose To morphologically, biochemically, and physiologically characterize corneal cross-linking with riboflavin and UV-A light (CXL) in a newly established in vivo murine model. Methods C57BL/6 wild-type mice (N = 67) were treated with various CXL protocols, with modification of the following parameters: total energy (fluence) used, duration of UV-A irradiation, continuous versus pulsed irradiation, and CXL under hypoxic conditions (contact lens). Corneas were evaluated biomicroscopically, histologically, and using optical coherence tomography. Conformational collagen changes were evaluated via changes in the speed of enzymatic digestion. Results A fluence of 5.4 J/cm2 induced scar formation, while fluences of scar formation. Changes in the speed of enzymatic digestion suggest that CXL in mice, when compared to humans, requires less UV-A energy than the difference in corneal thickness between the species would suggest. Conclusions We demonstrated the in vivo response of very strong and very weak CXL and identified the best suited range of UV fluence in murine corneas. The presented murine CXL model may be helpful in future research addressing cellular and molecular pathways associated to CXL treatment. Translational Relevance Adverse tissue reactions following CXL treatment were observed, if the administered UV energy was out of the treatment window—raising concern about novel CXL treatment protocols that have not been previously validated in an experimental setting. PMID:28149672

  5. 准分子激光角膜屈光术后角膜感染诊断与治疗回顾%Review the diagnosis and treatment of infection of the cornea after excimer laser cornea refractive surgery

    Institute of Scientific and Technical Information of China (English)

    李韵秋; 李静; 王梦雅; 李从心; 李素霞; 史伟云; 王婷

    2015-01-01

    目的:回顾性分析准分子激光角膜屈光术后早期角膜感染的诊断与治疗策略及视力转归。方法对2008年1月至2014年3月我院收治的因准分子激光术后早期角膜感染患者7例(8只眼)进行回顾性分析。根据患者病史、共焦显微镜或角膜病灶组织刮片等检查明确其感染类型,对症采用局部及全身药物治疗,对药物不能控制的感染采取手术治疗,并观察视力转归情况。结果患者8只眼全部诊断为细菌性角膜溃疡,其中8只眼病灶组织刮片检查为阳性,5只眼细菌培养阳性。4只眼(50.0%)经抗菌药物治疗达到溃疡愈合,4只眼(50.0%)行板层性角膜移植术治愈。治愈病例至溃疡愈合时,8只眼视力均较治疗前提高。结论感染性角膜炎是准分子激光术后早期发生的严重并发症,尽早明确诊断并积极治疗是控制感染、保存视力的关键。%Objective Retrospective analysis of diagnosis and treatment strategies and visual acuity outcomes of the early corneal infection after excimer laser cornea refractive surgery.Methods Retrospective analysis 7 patients 8 eyes early postoperative corneal infection after excimer laser who treated in our hospital in 2008 January to 2014 March.Confirm the type of infection according to patient history, confocal microscopy or corneal tissue scraping test , using local and sys-temic drug treatment, take the operation if drug can not control the infection, and observe the visual prognosis.Results All patients with 8 eyes diagnosed as bacterial corneal ulcer, 8 eyes Lesions tissue smear examination, 5 eyes of bacterial culture were positive.4 eyes (50%) after anti bacteria drug treatment to the healing of ulcer, 4 eyes (50%) taking lamel-lar keratoplasty to cure.To the healing of ulcers, visual acuity of 8 eyes was improved compared with those before treat-ment.Conclusion Infective keratitis is a severe complication occ-urred after

  6. The management of cornea blindness from severe corneal scarring, with the Athens Protocol (transepithelial topography-guided PRK therapeutic remodeling, combined with same-day, collagen cross-linking

    Directory of Open Access Journals (Sweden)

    Kanellopoulos AJ

    2012-02-01

    Full Text Available Anastasios John KanellopoulosLaservision.gr Institute, Athens, Greece; Manhattan Eye, Ear and Throat Hospital, New York, NY, USA; New York University Medical School, New York, NY, USAPurpose: To evaluate the safety and efficacy of combined transepithelial topography-guided photorefractive keratectomy (PRK therapeutic remodeling, combined with same-day, collagen cross-linking (CXL. This protocol was used for the management of cornea blindness due to severe corneal scarring.Methods: A 57-year-old man had severe corneal blindness in both eyes. Both corneas had significant central scars attributed to a firework explosion 45 years ago, when the patient was 12 years old. Corrected distance visual acuity (CDVA was 20/100 both eyes (OU with refraction: +4.00, –4.50 at 135° in the right eye and +3.50, –1.00 at 55° in the left. Respective keratometries were: 42.3, 60.4 at 17° and 35.8, 39.1 at 151.3°. Cornea transplantation was the recommendation by multiple cornea specialists as the treatment of choice. We decided prior to considering a transplant to employ the Athens Protocol (combined topography-guided partial PRK and CXL in the right eye in February 2010 and in the left eye in September 2010. The treatment plan for both eyes was designed on the topography-guided wavelight excimer laser platform.Results: Fifteen months after the right eye treatment, the right cornea had improved translucency and was topographically stable with uncorrected distance visual acuity (UDVA 20/50 and CDVA 20/40 with refraction +0.50, –2.00 at 5°. We noted a similar outcome after similar treatment applied in the left eye with UDVA 20/50 and CDVA 20/40 with –0.50, –2.00 at 170° at the 8-month follow-up.Conclusion: In this case, the introduction of successful management of severe cornea abnormalities and scarring with the Athens Protocol may provide an effective alternative to other existing surgical or medical options.Keywords: Athens Protocol, collagen cross

  7. Histogenesis and cellular apoptosis of the mouse cornea%小鼠角膜的发生与细胞凋亡

    Institute of Scientific and Technical Information of China (English)

    李雪; 王强; 陈文静; 刘彬; 邓锦波

    2013-01-01

    目的 通过观察小鼠角膜的发生过程,探讨角膜细胞的增殖与凋亡对角膜结构修复与塑形的作用.方法 各日龄共计120只小鼠,用HE染色或4’,6-二脒基-2-苯基吲哚(DAPI)染色对小鼠角膜的一般结构进行观察;用5’-溴脱氧尿嘧啶核苷(BrdU)技术标记角膜增殖细胞和免疫荧光法标记干细胞和凋亡细胞.结果 胚胎发育及出生后早期,角膜以实质层的发育为主.出生14d(P14)左右,角膜上皮细胞层开始增殖分化为两层细胞,同时内皮细胞也开始分化.至P30时,我们可以辨别出角膜的6层结构.BrdU阳性细胞主要存在实质层中的成纤维细胞,出生以后也可见于角膜上皮细胞层和内皮细胞层.随着角膜发育,P10左右,其他层的BrdU阳性细胞都消失,仅存在于角膜上皮细胞层.增殖细胞核抗原(PCNA)阳性细胞在发育早期散在分布于角膜的各层,P14以后PCNA阳性细胞均匀的分布于角膜上皮细胞的基底层,并维持在稳定状态.在角膜发育早期,在各层可见许多细胞凋亡.结论 角膜的发育与其感光功能形成的过程相一致,角膜干细胞的增殖与其修复有关;有大量的凋亡细胞参与角膜结构的塑形.%Objective Our aim was to observe the histogenesis, cellular proliferation and apoptosis of the mouse cornea. Methods A total of 120 mice were used in the study. HE staining and DAPI staining were used to observe the general structure of the mouse cornea. Brdu detetion and immunofluorescent labeling were carried out to study corned proliferating cell, stem cells apoptic cells. Caspase-8 immunofluorescent staining was uesd to detect corneal apoptotic cells. Results During embryonic development and early postnatal stage, the stroma layer was observed in the developing cornea. About P14, the corneal epithelial cell layer began to proliferate and differentiate into two layers, with differentiation of endothelial cells. At P30 the six-layer structure of the

  8. Investigation of Cornea Donation Cognition and Willing of College Students, Daqing%大庆市大学生对角膜捐献的认知及捐献意愿调查

    Institute of Scientific and Technical Information of China (English)

    赵楠; 王彩霞

    2015-01-01

    目的:了解大学生角膜捐献知识及捐献意愿现状,探讨相关影响因素.方法:分层整群抽取大庆市3所高校1040名在校大学生,以问卷调查形式对角膜捐献知识及捐献意愿现状进行调查.结果:不同特征大学生对角膜捐献知晓情况不同,差异有统计学意义;整体上看,大学生关于角膜捐献具体知识了解较少,医学生与非医学生的认知差异有统计学意义.64.5%的大学生愿意捐献角膜,35.5%的大学生暂时不愿意捐献角膜,性别、年级、是否听说过角膜捐献、是否知道角膜供体紧缺、是否了解医学伦理学知识及社会对角膜捐献的支持与鼓励力度与身后捐献角膜意愿有关.结论:高校大学生对角膜捐献知识了解较少,但捐献意愿较高,应该有针对性地进行角膜捐献知识的宣传普及,完善角膜捐献渠道及相关法律法规.%Objective: To understand the current status of knowledge and willingness of cornea donation of college students, and to analyze its influencing factors.Methods:1040 students from 3 universities were selected with stratified cluster sampling method, and the questionnaires were used to analyze their knowledge and willingness of cornea donation .Results: Different students had different cognition on cornea donation with statistical significance (P <0.05).The overall respondents had a poor knowledge on cornea donation, with statistically significant differences between medical and non-medical students (P <0.05), and 64.5% of them were willing to donate cornea donation with 35.5% not.The students'gender, grade, whether knowing the cornea donation and the shortage of donor, and medical ethics knowledge and the social support and encourage on cornea donation were related to their donation willingness.Conclusion: College students'cornea donation knowledge is not enough but their donation willingness is high.Strategies such as promoting and popularizing knowledge of cornea donation, and

  9. Averaged spacing and 2-d organization of collagen fibrils in the posterior cornea of the rabbit eye assessed by transmission electron microscopy.

    Science.gov (United States)

    Doughty, Michael J

    2014-04-01

    To assess how reproducible collagen fibril spacing might be in the corneal stroma as viewed by transmission electron microscopy by calculating averaged values for the 2-D organization. One cornea from 8 albino rabbits (2 kg) was fixed in situ to preserve natural shape. Thin sections were stained with 2% phosphotungstic acid (PTA) and images taken of fibrils from the central-posterior stroma. After projection at 250,000 X magnification, an overlay was prepared of the fibrils. Using a 500 × 500 nm region of interest (ROI), the distances to all fibril centers were measured to 2 nm resolution. The sets of fibrils had average diameters between 32.4 and 36.1 nm (group mean ± SD of 34.4 ± 4.2 nm). The mean fibril density was 396 ± 21 per square micrometer, with a fibril area fraction of 38.7 ± 3.9%. The mean distance to the literal nearest neighbor fibril center was 43.2 ± 4.5 nm. A radial distribution analysis showed a distinct nearest neighbors peak at 51 nm. This nearest neighbors peak had an average amplitude of 2.236 ± 0.315, with a broader secondary peak being evident in all data sets centered at 93 nm with an average amplitude of 1.166 ± 0.093 (or 53.3 ± 7.1% of the nearest neighbors peak). Overall, these results show that a predictable 2-D organization can be demonstrated for collagen fibrils in rabbit corneas when consideration is given to sample selection and preparation and the image analysis strategy.

  10. The grave necessity to make eye bank specular microscopy mandatory in all eye banks in the subcontinent to improve utilization of scarce donor corneas

    Directory of Open Access Journals (Sweden)

    Jagruti N Jadeja

    2013-01-01

    Full Text Available Context: Donor tissue scarcity, Eye Bank Specular Microscopy as yet not made mandatory and tissue utilization often based on clinical judgment only. Aims: Prospectively analyze alteration in clinical grading of donor corneas and hence utilization, based on Eye Bank Specular Microscopy (EBSM and to infer if EBSM should be mandatory in all eye banks. Materials and Methods: 200 consecutive otherwise ′suitable for surgery′ donor eyes were graded clinically. On quantitative and qualitative analysis of endothelial cells by EBSM, final grading was adjusted. Impact on subsequent utilization for various surgeries was analyzed with regard to Age of Donor, Death to Enucleation Time, Death to Preservation Time and Lens Status of Donor Eye. Results: 76 eyes (38% (P 60 years showed CD >= 2500. From donor >=81 years, 2/13 (15.3% eyes showed CD between 2501-3000 and 1 (7.6% eye showed CD > 3000. Owing to better grading after EBSM, 13/14 (92.85% tissues with DTET >6 hours and 5/5 (100% tissues with DTPT > 16 hours were transplanted. Out of 45 (22.5% pseudo-phakic tissues, 21 (46.67% tissues were used for Therapeutic/Tectonic Penetrating Keratoplasty (PKP while 24 (53.33% tissues were used for Optical PKP. Conclusions: EBSM significantly alters final grading of tissues and its subsequent utilization. Acquiring huge importance in areas where adequate supply of corneas is lacking, EBSM becomes an indispensable tool for optimizing availability of qualified tissues for surgery. EBSM should be made a mandatory analysis.

  11. Transplantation of reconstructed corneal layer composed of corneal epithelium and fibroblasts on a lyophilized amniotic membrane to severely alkali-burned cornea.

    Science.gov (United States)

    Jang, In-Keun; Ahn, Jae-Il; Shin, Jun-Seop; Kwon, Young-Sam; Ryu, Yang-Hwan; Lee, Jeong-Kyu; Park, Jung-Keug; Song, Kye-Yong; Yang, Eun-Kyung; Kim, Jae-Chan

    2006-06-01

    The purpose of this article was to evaluate the graft efficacy of reconstructed corneal layer, composed of autologous corneal epithelium and fibroblasts on a lyophilized amniotic membrane (LAM), in a severely alkali-burned corneal model. After biopsy specimens were obtained from the left eyes of 24 rabbits, the corneal epithelial cells and fibroblasts were expanded in vitro and the corneal layer was reconstructed on LAM. Thirty-six eyes of rabbits underwent alkali burn (1 N NaOH, 30 s) to create a limbal deficiency and a deeply damaged corneal stroma. Four weeks later, group 1 underwent a graft of the reconstructed corneal layer composed of autologous corneal epithelium and fibroblasts on LAM. Group 2 was transplanted with a graft of the reconstructed autologous corneal epithelium, and group 3 served as a control without surgery. Wound healing and stabilization of the ocular surfaces occurred much faster in group 1 than in groups 2 and 3. The eyes in group 3 revealed typical limbal deficiencies with conjuctivalization and persistent corneal epithelial defects. However, the corneas in group 1 developed only mild peripheral neovascularization. Immunohistochemical staining in group 1 demonstrated that p63, cytokeratin 3, E-cadherin, transforming growth factor (TGF)-beta1, and collagen IV were expressed strongly in the corneal epithelium and basement membrane. On the basis of these results, transplantation of the reconstructed corneal layer, composed of autologous corneal epithelium and fibroblasts on LAM, partially accelerated the recovery of the alkali-injured rabbit ocular surface, and might be useful therapeutically for the treatment of patients with severely damaged cornea.

  12. Central Corneal Thickness Measurement Using Ultrasonic Pachymetry, Rotating Scheimpflug Camera, and Scanning-slit Topography Exclusively in Thin Non-keratoconic Corneas

    Science.gov (United States)

    Mohammadpour, Mehrdad; Mohammad, Kazem; Karimi, Nasser

    2016-01-01

    Purpose: To evaluate the agreement among Pentacam, Orbscan and ultrasound (US) pachymetry for measurement of central corneal thickness (CCT) in thin corneas with normal topographic pattern. Methods: We included 88 eyes of 44 refractive surgery candidates with thinnest pachymetric readings of 500 micrometers (μm) or less on Orbscan, a normal topographic pattern, no sign of keratoconus, and best corrected visual acuity (BCVA) of 20/20. Pentacam, Orbscan and US were performed in one session by the same examiner. Exclusion criteria were history of ocular surgery, topographic abnormalities suggesting forme fruste keratoconus or keratectasia, and recent contact lens wear. Results: The difference in CCT measurements by US pachymetry and Orbscan II [using an acoustic factor (AF) of 0.92] ranged from −34 to +34 μm. The difference between the thinnest point and central readings measured by US reached 16 μm with Orbscan II (AF: 0.92) and 2 μm with Pentacam. Mean differences between the employed devices were 0.2 μm for Pentacam versus US (P = 0.727), 30.1 μm for uncorrected Orbscan versus US (P < 0.001), 10.4 μm for Orbscan II (AF = 0.92) versus US (P < 0.001), and 0.2 μm for Orbscan II (AF = 0.94) versus US (P = 0.851). Conclusion: In normal thin corneas, Pentacam demonstrated better agreement with US pachymetry as compared to corrected Orbscan readings. Results achieved by Orbscan were better consistent with US pachymetry using an AF of 0.94. We speculate that a dynamically graded AF in reverse proportion to CCT constitutes a better approach for correcting Orbscan measurements. PMID:27621779

  13. Eye Gaze Tracking Method Based on Pupil Center Cornea Reflection Technique%基于瞳孔-角膜反射技术的视线跟踪方法

    Institute of Scientific and Technical Information of China (English)

    吴广发; 宋鸿陟; 黄生辉

    2014-01-01

    视线跟踪是基于多通道的人机交互技术的重要研究内容,而基于瞳孔-角膜反射技术的视线方向是目前应用最广泛的视线跟踪技术之一。瞳孔-角膜反射技术的主要目的是提取人眼图像中瞳孔-角膜反射向量作为视线方向计算模型所需的视觉信息,通过搭建红外光源设备提取瞳孔-角膜反射向量构建基于瞳孔-角膜反射技术的视线跟踪系统,为面向人机交互的视线跟踪研究提供可行的低成本解决方案。%Eye gaze tracking is an important research content of human-computer interaction technology based on multiple channels, and the gaze estimation based on pupil center cornea reflection technique is one of eye gaze tracking technologies with the widest application. The pri-mary purpose of pupil center cornea reflection technique is to extract the pupil center cornea reflection vector in human eye image as the vision information of gaze estimation model. Constructs an infrared light device to extract the pupil center cornea reflection vector and builds up an eye gaze tracking system based on pupil center cornea reflection technique, provides a feasible and low-cost solution for the eye gaze tracking research of human-computer interaction.

  14. 辅助角膜移植显微手术机器人系统的实验性应用研究%Operation of cornea grafting micro-surgery robot system

    Institute of Scientific and Technical Information of China (English)

    梁庆丰; 李大寨; 胡一达; 魏东; 邓世靖; 孙旭光

    2009-01-01

    目的 探讨辅助角膜移植显微手术机器人系统的实验性应用效果.方法 实验研究.采用人机协同手术方式,建立具有6个子系统的角膜移植显微手术机器人系统,并对20只兔眼角膜进行钻切、缝合实验;观察手术目标定位误差、切口圆周对称性、角膜钻切深度及缝合跨距等指标.结果 20只角膜钻切、缝合手术操作均按照机器人及计算机导航系统的预定程序完成,其手术钻切中心定位误差为(0.356±0.040)mm,切口横纵跨度比为(0.855±0.040),角膜圆周不同位置钻切深度误差小于10 μm,病理组织切片可见角膜切缘整齐,角膜切口附近各层组织结构及厚度无明显变化;缝合装置的缝合跨距(2.15±0.09)mm,与目标跨距2.00 mm误差(0.15±0.02)mm.结论 辅助角膜移植显微手术机器人系统设计合理;系统的基本功能可满足角膜移植手术的要求;在实验动物的角膜钻切、缝合过程中具有较好的稳定性和准确性.%Objective To design the robotic mechanism of the cornea grafting micro-surgery system and evaluate its experimental feasibility and efficacy. Methods It was an experimental study. Based on computer assisted cornea grafting surgery ( CACGS), the prototype about cornea grafting robot, which consists of six subsystems, was developed. The system was used for looping incision and suturing for 20 rabbit corneas. Experimental data were studied including the error of target incision position, the actual cutting depth and the cutting edge span in order to evaluate the system's clinical value. All above statistical descriptions were performed using SPSS software version 11.5. Results 20 corneas were looping incised and sutured by the robot-assisted cornea grafting micro-surgery system successfully. The error of target incision position was (0.356±0.040)mm. With CACGS, the cutting edge span (A) was (0.855±0.040) and the actual cutting depth error was less than 10 p,m. Corneal structure

  15. 正常与病态眼角膜蠕变特性的对比分析%Comparative Analysis of the Creep Mechanical Characteristic of the Normal and the Morbid Cornea

    Institute of Scientific and Technical Information of China (English)

    李爽; 袁毅

    2012-01-01

    To compare the creep mechanical characteristics of the normal cornea and the morbid cornea and provide the biome-chanical parameter for the clinical medicine. 20 corneas were divided into two groups. 10 corneas (the rest part of the cornea after transplantation) belonged to the normal group and the other 10 ones (the abandoned part of the severe ulcer corneal after operation) belonged to the morbid group. The creep experiment was done with the electronic universal testing machine, increasing the stress at the speed of 0. 1 MPa per second. The data with the normalized analysis method was analyzed. The creep quantity of the normal group in 7 200 s was 0. 16% . The creep quantity of the morbid one in 7 200 s was 0. 12%. The creep quantity of the normal group was more than the morbid one and the differences were significant (P < 0. 05). The creep curves of the normal group and the morbid one change exponentially. The creep characteristics of the cornea in the morbid group has changed.%比较正常和病态眼角膜的蠕变力学特性为临床提供生物力学参数.采用人工捐献角膜,角膜移植后的10个眼角膜剩余部分、严重角膜溃疡术后严重并发症行角膜移植患者的病态眼角膜遗弃部分10个,在电子万能试验机上以0.1 Mpa/s的应力增加速度进行蠕变实验.以归一化分析的方法处理蠕变实验数据.正常对照组眼角膜7 200s蠕变量为0.16%,病态组眼角膜7 200s蠕变量为0.12%,正常对照组7 200s蠕变量大于病态组,差异显著(P<0.05).蠕变曲线是以指数关系变化的,病态组眼角膜蠕变特性发生改变.

  16. The generation of 4-hydroxynonenal, an electrophilic lipid peroxidation end product, in rabbit cornea organ cultures treated with UVB light and nitrogen mustard

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Ruijin; Po, Iris; Mishin, Vladimir; Black, Adrienne T. [Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Heck, Diane E. [Environmental Science, New York Medical College, Valhalla, NY (United States); Laskin, Debra L. [Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Sinko, Patrick J. [Pharmaceutics, Rutgers University, Piscataway, NJ (United States); Gerecke, Donald R.; Gordon, Marion K. [Pharmacology and Toxicology, Rutgers University, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Environmental and Occupational Medicine, UMDNJ-Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    2013-10-15

    The cornea is highly sensitive to oxidative stress, a process that can lead to lipid peroxidation. Ultraviolet light B (UVB) and nitrogen mustard (mechlorethamine) are corneal toxicants known to induce oxidative stress. Using a rabbit air-lifted corneal organ culture model, the oxidative stress responses to these toxicants in the corneal epithelium was characterized. Treatment of the cornea with UVB (0.5 J/cm{sup 2}) or nitrogen mustard (100 nmol) resulted in the generation of 4-hydroxynonenal (4-HNE), a reactive lipid peroxidation end product. This was associated with increased expression of the antioxidant, heme oxygenase-1 (HO-1). In human corneal epithelial cells in culture, addition of 4-HNE or 9-nitrooleic acid, a reactive nitrolipid formed during nitrosative stress, caused a time-dependent induction of HO-1 mRNA and protein; maximal responses were evident after 10 h with 30 μM 4-HNE or 6 h with 10 μM 9-nitrooleic acid. 4-HNE and 9-nitrooleic acid were also found to activate Erk1/2, JNK and p38 MAP kinases, as well as phosphoinositide-3-kinase (PI3)/Akt. Inhibition of p38 blocked 4-HNE- and 9-nitrooleic acid-induced HO-1 expression. Inhibition of Erk1/2, and to a lesser extent, JNK and PI3K/Akt, suppressed only 4-HNE-induced HO-1, while inhibition of JNK and PI3K/Akt, but not Erk1/2, partly reduced 9-nitrooleic acid-induced HO-1. These data indicate that the actions of 4-HNE and 9-nitrooleic acid on corneal epithelial cells are distinct. The sensitivity of corneal epithelial cells to oxidative stress may be an important mechanism mediating tissue injury induced by UVB or nitrogen mustard. - Highlights: • UVB or nitrogen mustard causes rabbit corneal epithelial injury. • 4-Hydroxynonenal (4-HNE) was formed and heme oxygenase-1 (HO-1) was increased. • 4-HNE induced HO-1 mRNA and protein expression in human corneal epithelial cells. • The induction of HO-1 by 4-HNE was through MAP kinase activation.

  17. 正常与病态眼角膜应力松弛力学特性的对比分析%The Comparative Analysis of Stress Relaxation Characteristics of Normal and Pothologycal Cornea

    Institute of Scientific and Technical Information of China (English)

    李爽; 李鹏; 袁毅

    2013-01-01

    通过建立正常与病态眼角膜的应力松弛函数方程、应力松弛曲线,比较正常和病态眼角膜的应力松弛力学为临床提供生物力学参数。正常人尸体眼角膜和病态(眼角膜移植患者的眼角膜)眼角膜各10个,在电子万能试验机上进行应力松弛实验。模拟人体温在36.5±0.5℃的温度下,以0.1%/s的应变增加速度对试样施加拉应变,采集100个数据,以归一化分析的方法处理应力松弛数据,拟合应力松弛曲线。正常对照组眼角膜7200 s应力松弛量为0.61 MPa,病态组眼角膜7200 s应力松弛量为0.46 MPa,正常对照组7200 s应力松弛量大于病态组,差异显著(P<0.05)。应力松弛曲线是以对数关系变化的,病态组眼角膜应力松弛特性发生改变。%To compare the stress relaxation mechanics of normal and morbid state corneas by establishing normal and the morbid state cornea stress relaxation functional equation and the stress relaxation curve,and to provide the biological mechanical parameters for clinical.10 corneas of the normal persons′corpse cornea and the morbid state (the corneas of patients with transplanted corneas) corneas were taken respectively,and then the stress relaxation experiment was conducted with electronic universal testing machine.We simulated human body temperature at a temperature of 36.5 ±0.5 ℃,and then applied a tensile strain in the sample 0.1%/state of increase of the strain,and collected 100 data,then the stress relaxation data were dealed with normalized analysis method,and finally the stress relaxation curve was fitted.The stress relaxation quantity of the coreas of the normal control group at 7 200 s was 0.61 MPa, the stress relaxation quantity of the corneas of the morbid state group at 7 200 s was 0.46 MPa,the stress relaxation quantity of normal control group at 7 200 s was more than that of the morbid state group,and the differences were obviously (P<0

  18. Controlled reshaping of the front surface of the cornea through its full-area ablation outside of the optical zone with a Gaussian ArF excimer laser beam

    Science.gov (United States)

    Semchishen, A. V.; Semchishen, V. A.

    2014-01-01

    We studied in vitro the response of the topography of the cornea to its full-area laser ablation (the laser beam spot diameter is commensurable with the size of the interface) outside of the central zone with an excimer laser having a Gaussian fluence distribution across the beam. Subject to investigation were the topographically controlled surface changes of the anterior cornea in 60 porcine eyes with a 5 ± 1.25-diopter artificially induced astigmatism, the changes being caused by laser ablation of the stromal collagen in two 3.5-mm-dia. circular areas along the weaker astigmatism axis. Experimental relationships are presented between the actual astigmatism correction and the expected correction for the intact optical zones 1, 2, 3, and 4 mm in diameter. The data for each zone were approximated by the least-squares method with the function d = a + bx. The coefficient b is given with the root-mean-square error. The statistical processing of the data yielded the following results: d = (0.14 ± 0.037)x for the 1-mm-dia. optical zone, (1.10 ± 0.036)x for the 2-mm-dia. optical zone, (1.04 ± 0.020)x for the 3-mm-dia. optical zone, and (0.55 ± 0.04)x for the 4-mm-dia. optical zone. Full astigmatism correction was achieved with ablation effected outside of the 3-mm-dia. optical zone. The surface changes of the cornea are shown to be due not only to the removal of the corneal tissue, but also to the biomechanical topographic response of the cornea to its strain caused by the formation of a dense pseudomembrane in the ablation area.

  19. Neuroprotective Effects of Sulphated Agaran from Marine Alga Gracilaria cornea in Rat 6-Hydroxydopamine Parkinson's Disease Model: Behavioural, Neurochemical and Transcriptional Alterations.

    Science.gov (United States)

    Souza, Ricardo Basto; Frota, Annyta Fernandes; Sousa, Rayane Siqueira; Cezario, Nayara Araújo; Santos, Tarcizio Brito; Souza, Luziana Mara Frota; Coura, Chistiane Oliveira; Monteiro, Valdécio Silvano; Cristino Filho, Gerardo; Vasconcelos, Silvânia Maria Mendes; da Cunha, Rodrigo Maranguape Silva; Aguiar, Lissiana Magna Vasconcelos; Benevides, Norma Maria Barros

    2017-02-01

    Parkinson's disease (PD) is a multifactorial disease associated with the degeneration of dopaminergic neurons and behavioural alterations. Natural bioactive compounds may provide new therapeutic alternatives for neurodegenerative disorders, such as PD. The sulphated polysaccharides isolated from marine algae are heterogenic molecules that show different biological activities. The red marine alga Gracilaria cornea has a sulphated polysaccharide (SA-Gc) with structure and anti-inflammatory and antinociceptive activities reported in the literature. Therefore, this study aimed to evaluate the neuroprotective effects of SA-Gc in rat model PD induced by 6-hydroxydopamine (6-OHDA). Firstly, we established the PD model in rats, induced by an intrastriatal injection (int.) of 6-OHDA, followed by a single administration of SA-Gc (15, 30 or 60 μg; int.). On the 14th day, behavioural tests were performed. After killing, brain areas were dissected and used for neurochemical and/or transcriptional analyses. The results showed that SA-Gc (60 μg, int.) promoted neuroprotective effects in vivo through reducing the oxidative/nitroactive stress and through alterations in the monoamine contents induced by 6-OHDA. Furthermore, SA-Gc modulated the transcription of neuroprotective and inflammatory genes, as well as returning behavioural activities and weight gain to normal conditions. Thus, this study reports the neuroprotective effects of SA-Gc against 6-OHDA in rats.

  20. 人角膜接触镜材料生物相容性的研究%Studies on biocompatibility of contact lens material for human cornea

    Institute of Scientific and Technical Information of China (English)

    朱文渊; 刘正堂; 崔英德; 黎新明

    2007-01-01

    Objective To study the biocompatibility of contact lens material for human cornea prepared in our department. Methods Biological properties of the material were assessed by cytotoxicity,haemolysis and protein aggradation. Results The material had no toxicity for HEFC. The haemolysis rate was eligibility(1.62%). Anti-protein-aggradation was quite good. Conclusion The contact lens material by our department possesses quite good biological properties.%目的 研究本室制备的人角膜接触镜材料的生物性能.方法 采用细胞毒性试验、红细胞溶血试验以及蛋白质沉积试验方法.结果 所制备的人角膜接触镜材料对人胚肺纤维细胞(HEFC)毒性评价为1级无毒性;红细胞溶血率为1.62%合格;在体温范围内抗蛋白质沉积作用较好.结论 本室制备的人角膜接触镜材料具有较好的生物相容性.

  1. Monitoring of cornea elastic properties changes during UV-A/riboflavin-induced corneal collagen cross-linking using supersonic shear wave imaging: a pilot study.

    Science.gov (United States)

    Nguyen, Thu-Mai; Aubry, Jean-François; Touboul, David; Fink, Mathias; Gennisson, Jean-Luc; Bercoff, Jeremy; Tanter, Mickael

    2012-08-31

    Keratoconus disease or post-LASIK corneal ectasia are increasingly treated using UV-A/riboflavin-induced corneal collagen cross-linking (CXL). However, this treatment suffers from a lack of techniques to provide an assessment in real-time of the CXL effects. Here, we investigated the potential interest of corneal elasticity as a biomarker of the efficacy of this treatment. For this purpose, supersonic shear wave imaging (SSI) was performed both ex vivo and in vivo on porcine eyes before and after CXL. Based on ultrasonic scanners providing ultrafast frame rates (~30 kHz), the SSI technique generates and tracks the propagation of shear waves in tissues. It provides two- and three-dimensional (2-D and 3-D) quantitative maps of the corneal elasticity. After CXL, quantitative maps of corneal stiffness clearly depicted the cross-linked area with a typical 200-μm lateral resolution. The CXL resulted in a 56% ± 15% increase of the shear wave speed for corneas treated in vivo (n = 4). The in vivo CXL experiments performed on pigs demonstrated that the quantitative estimation of local stiffness and the 2-D elastic maps of the corneal surface provide an efficient way to monitor the local efficacy of corneal cross-linking.

  2. 准分子激光原位角膜磨镶术不同厚度角膜瓣的临床评估%Clinical evaluation on the cornea flap with different thickness after LASIK

    Institute of Scientific and Technical Information of China (English)

    张丰菊; 陈丽娜; 郭宁; 于芳蕾; 鲁智莉

    2009-01-01

    目的 利用共焦显微镜观察厚、薄角膜瓣各层组织在形态学方面改变的区别,同时比较准分子激光原位角膜磨镶术(LASIK)后厚、薄角膜瓣的视功能差异,以期为临床合理化手术提供客观依据.方法 病例对照研究.收集行LASIK手术的患者70例(70只眼),平均年龄(23±5)岁.按照角膜瓣厚度分为两组:薄角膜瓣组(A组,36只眼)和厚角膜瓣组(B组,34只眼),术前平均等值球镜屈光度数分别为(-4.76±2.30)和(-3.03±2.20)D.术前术后均进行视力、屈光度、波阵面像差、对比敏感度等视功能检查,同时应用共焦显微镜(海德堡视网膜断层扫描仪角膜模块,HRTⅢ)检测角膜中央各层组织.数据应用配对t检验进行统计学分析,以P0.05).IASIK术后两组角膜瓣厚度分别为(107.37±20.5)和(149±25.2)μm,皱褶厚度分别为(63.71±15.8)和(48.16±20.7)μm,无细胞区厚度分别为(69.93±15.8)和(55.63±23.7)μm,激活角膜细胞区厚度分别为(60.15±30.9)和(51.86±27.9)μm;前基质细胞密度分别为(825.14±156.9)和(853.54±126.8)个/mm2;各项差异均有统计学意义(t=2.679,1.974,3.051,2.196,3.146;P0.05).术前及术后不同时间两组的各阶像差及对比敏感度差异均无统计学意义(P>0.05).结论 准分子激光原位角膜磨镶术中采用的角膜瓣厚度不同,术后虽然其临床视功能比较并无明显差异,但是厚、薄角膜瓣愈合时在细胞水平存在较大差异,角膜瓣与基质之间是非瘢痕性愈合.角膜薄瓣在细胞水平对角膜组织损伤的程度重于角膜厚瓣.(中华眼科杂志,2009,45:587-593)%Objective To investigate morphologically the different changes of cornea tissue between thick and thin cornea flap with confocal microscope, and to compare visual function between thick and thin cornea flap after LASIK Methods 70 eases (70 eyes) who had received LASIK were divided into the thin cornea flap group (36eyes, group A) and the thick cornea flap group

  3. 改良结膜筋膜覆盖角膜术在眼球萎缩整形中的应用%Application of improved conjunctival and balbar fascia flap cornea coverlaying in traumatic atrophic eyeball for anaplasty

    Institute of Scientific and Technical Information of China (English)

    刘凤霞; 张松; 王彦; 刘德成

    2016-01-01

    目的 探讨保留外伤性萎缩眼球配戴薄型义眼的方法与临床效果.方法 轻中度外伤眼球萎缩32例(32眼).术中将萎缩眼球的角膜浅层基质和角膜缘上皮组织彻底清除,将上方球结膜和眼球筋膜同时向下滑行,覆盖整个角膜并固定于下方角膜缘,与下方眼球筋膜及结膜缝合.术后1个月定做义眼片佩戴,随访6 ~ 24个月,观察其效果.结果 32例结膜筋膜覆盖良好,无角膜暴露,患者无异物感,双侧睑裂对称,外观改善满意.结论 轻中度外伤性眼球萎缩采用改良结膜眼球筋膜瓣覆盖角膜,术后愈合良好,角膜不暴露,结膜囊成形好,佩戴个性化义眼片,可达到美容效果.%Objective To investigate the method and clinical effect of wearing thin-walled ocular prosthesis after conjunctival and bulbar fascia flap coverlaying surgery of traumatic atrophic eyeball.Methods Total 32 eyes of 32 patients with mild-to-moderate traumatic atrophic eyeball were treated.In the operation,the superficial parenchyma of cornea and limbus epithelial tissue of atrophic eyeball were thoroughly removed,the above bulbar conjunctiva and bulbar fascia flap were slid downward to cover the whole cornea and fixed in the inferior limbus,and sutured with fascia and conjunctiva below.At 1 month postoperatively,customized personalized ocular prosthesis was used.The follow-up time was 6-24 months and the curative effect was observed.Results The conjunctiva fascia coverage of 32 patients were good without corneal exposure or foreign body sensation.The improved appearance was satisfactory.Conclusion Applying complete conjunctiva fascia flap to cover cornea in mild-to-moderate traumatic atrophic eyeball is effective.The healing of postoperative fascia and cornea is good,and the cornea is not exposed.The cosmetic effect of wearing personalized ocular prosthesis is good.

  4. Normal X-inactivation mosaicism in corneas of heterozygous FlnaDilp2/+ female mice--a model of human Filamin A (FLNA diseases

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    Douvaras Panagiotis

    2012-02-01

    Full Text Available Abstract Background Some abnormalities of mouse corneal epithelial maintenance can be identified by the atypical mosaic patterns they produce in X-chromosome inactivation mosaics and chimeras. Human FLNA/+ females, heterozygous for X-linked, filamin A gene (FLNA mutations, display a range of disorders and X-inactivation mosaicism is sometimes quantitatively unbalanced. FlnaDilp2/+ mice, heterozygous for an X-linked filamin A (Flna nonsense mutation have variable eye, skeletal and other abnormalities, but X-inactivation mosaicism has not been investigated. The aim of this study was to determine whether X-inactivation mosaicism in the corneal epithelia of FlnaDilp2/+ mice was affected in any way that might predict abnormal corneal epithelial maintenance. Results X-chromosome inactivation mosaicism was studied in the corneal epithelium and a control tissue (liver of FlnaDilp2/+ and wild-type (WT female X-inactivation mosaics, hemizygous for the X-linked, LacZ reporter H253 transgene, using β-galactosidase histochemical staining. The corneal epithelia of FlnaDilp2/+ and WT X-inactivation mosaics showed similar radial, striped patterns, implying epithelial cell movement was not disrupted in FlnaDilp2/+ corneas. Corrected stripe numbers declined with age overall (but not significantly for either genotype individually, consistent with previous reports suggesting an age-related reduction in stem cell function. Corrected stripe numbers were not reduced in FlnaDilp2/+ compared with WT X-inactivation mosaics and mosaicism was not significantly more unbalanced in the corneal epithelia or livers of FlnaDilp2/+ than wild-type Flna+/+ X-inactivation mosaics. Conclusions Mosaic analysis identified no major effect of the mouse FlnaDilp2 mutation on corneal epithelial maintenance or the balance of X-inactivation mosaicism in the corneal epithelium or liver.

  5. Clinical Outcomes of Small Incision Lenticule Extraction with Accelerated Cross-Linking (ReLEx SMILE Xtra in Patients with Thin Corneas and Borderline Topography

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    Sri Ganesh

    2015-01-01

    Full Text Available Purpose. To study the safety and clinical outcomes of ReLEx SMILE with accelerated cross-linking in individuals with thinner corneas, borderline topography, and higher refractive errors. Methods. Eligible patients first underwent SMILE procedure for correction of myopic refractive error. Following the removal of lenticule, 0.25% riboflavin in saline was injected into the interface and allowed to diffuse for 60 seconds. Finally, eye was exposed to UV-A radiation of 45 mW/cm2 for 75 seconds through the cap. Total energy delivered was 3.4 J/cm2. Results. 40 eyes of 20 patients with mean age of 26.75 ± 5.99 years were treated. Mean follow-up was 12 months ± 28.12 days. Mean spherical equivalent (SE was −5.02 ± 2.06 D preoperatively and −0.24 ± 0.18 D postoperatively. The mean central corneal thickness (CCT and keratometry changed from 501 ± 25.90 µm to 415 ± 42.26 µm and 45.40 ± 1.40 D to 41.2 ± 2.75 D, respectively. Mean uncorrected visual acuity (UCVA was 20/25 or better in all eyes. No eyes lost lines of corrected distant visual acuity (CDVA. There were no complications like haze, keratitis, ectasia, or regression. Conclusion. Based on the initial clinical outcome it appears that SMILE Xtra may be a safe and feasible modality to prevent corneal ectasia in susceptible individuals.

  6. Enucleaton of the right eye due to large choroidal melanoma with simultaneous penetrating cornea transplantation from OD to OS (Case report.

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    E. A. Korchuganova

    2014-07-01

    Full Text Available There is presentation case report of 75‑year old woman with choroidal melanoma (T3N0M0 on the right eye and failed graft on the left pseudophakic eye with far advanced glaucoma and ARMD. No treatment was given to the leading eye with VA 0,2. VA of OS = 1 / ∞ pr.l.certa; PKP OS in 2008 for pseudophakic bullous keratopathy on the eye with far advanced glaucoma. IOP was normal after previous filtering surgery. After PKP VA = 0,04; clear graft during 2 years; then gradually opacification and vascularization occurred. VA dropped to light perception. Echography OD — tumor h 8,29 mm, d 21,77 mm. No ingrowth of tumor into anterior segment of the eye; VA OD = 0 (no light perception. Concerning the need to enucleate the right eye with large choroidal melanoma, the advantage of using corneal autograft from OD to OS, location of tumor in the posterior pole with no ingrowth in anterior segment, the decision was made to perform the following operation — to enucleate the right eye and transplant simultaneously corneal graft from OD on OS. Patient was discharged from the Ophthalmology Hospital with VA OS = 0,01, during next week VA improved to 0,02. 8,0 mm graft isclear, fixed with 8 interruptured and continious suture 10 / 0‑nylon. Anterior chamber — normal depth, atrophic iris, stable position of PC IOL. Optic nerve head is pale with subtotal deep glaucomatous excavation. Conclusion: presented case report demonstrates the rarepossibility to use cornea after enucleation the eye with large malignant tumor (located in the posterior pole for grafting in the only eye with failed vascularised graft. It was the only possibility for this patient to restore some vision.

  7. Enucleaton of the right eye due to large choroidal melanoma with simultaneous penetrating cornea transplantation from OD to OS (Case report.

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    E. A. Korchuganova

    2013-01-01

    Full Text Available There is presentation case report of 75‑year old woman with choroidal melanoma (T3N0M0 on the right eye and failed graft on the left pseudophakic eye with far advanced glaucoma and ARMD. No treatment was given to the leading eye with VA 0,2. VA of OS = 1 / ∞ pr.l.certa; PKP OS in 2008 for pseudophakic bullous keratopathy on the eye with far advanced glaucoma. IOP was normal after previous filtering surgery. After PKP VA = 0,04; clear graft during 2 years; then gradually opacification and vascularization occurred. VA dropped to light perception. Echography OD — tumor h 8,29 mm, d 21,77 mm. No ingrowth of tumor into anterior segment of the eye; VA OD = 0 (no light perception. Concerning the need to enucleate the right eye with large choroidal melanoma, the advantage of using corneal autograft from OD to OS, location of tumor in the posterior pole with no ingrowth in anterior segment, the decision was made to perform the following operation — to enucleate the right eye and transplant simultaneously corneal graft from OD on OS. Patient was discharged from the Ophthalmology Hospital with VA OS = 0,01, during next week VA improved to 0,02. 8,0 mm graft isclear, fixed with 8 interruptured and continious suture 10 / 0‑nylon. Anterior chamber — normal depth, atrophic iris, stable position of PC IOL. Optic nerve head is pale with subtotal deep glaucomatous excavation. Conclusion: presented case report demonstrates the rarepossibility to use cornea after enucleation the eye with large malignant tumor (located in the posterior pole for grafting in the only eye with failed vascularised graft. It was the only possibility for this patient to restore some vision.

  8. The Changes of TGF-α, TGF-β1 and Basic FGF Messenger RNA Expression in Rabbit Cornea after Photorefractive Keratectomy

    Institute of Scientific and Technical Information of China (English)

    Yisheng Zhong; Yingrning Zhou; Jingcai Lian; Wen Ye; Kangsun Wang; Feng Cheng

    2000-01-01

    Objective: To study the mechanism of haze formation and investigate the expression changes of transforming growth factor-αα(TGF-αα), transforming growth factor-β1 (TGF-β1)and basic fibroblast growth factor (bFGF) mRNA in corneal epithelium and stroma after photorefractive keratectomy (PRK).Methods: Sixteen white rabbits were randomly divided into 4 groups, and PRK was performed on each eye of 12 rabbits. The haze formation was examined under a slit-lamp microscope at the 1st, 2na and 3ra month after PRK, and the expressions of TGF-αα , TGF-βi and bFGF mRNA were detected with in situ hybridization.Results: The corneal haze formed at the 1st month after PRK. The most prominent haze formation was observed at the 2nd month, and declined gradually at the 3ra month after ablation. TGF-αα mRNA expression was presented on the normal corneal epithelium and not on the corneal stroma. TGF-βl and bGFG mRNA were expressed by both corneal epitheliurn and stroma. The capacities for cornea tissue expression of three growth factors mRNA increased after PRK, and the peaks appeared on the 1s, 2na month. The extent for expressions of three growth factors related proportionally to the haze formation.Conclusion: Three growth factors took part in promoting corneal wound healing after PRK, and might contribute to corneal haze formation and development.

  9. Motivos do descarte de córneas captadas pelo banco de olhos do Hospital São Paulo em dois anos Discarding causes of cornea collected by eye bank of São Paulo hospital in two years

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    Carla Galluzzi dos Santos

    2010-02-01

    Full Text Available OBJETIVO: Analisar os motivos do descarte ou não utilização de córneas doadas, cujos tecidos foram captados, preservados e avaliados pelo Banco de Olhos do Hospital São Paulo no período de outubro de 2002 a setembro de 2004. MÉTODOS: Estudo retrospectivo analisando os prontuários com as seguintes informações sobre as doações: história clínica e ocular do doador, idade, causa mortis, resultados de exames sorológicos, avaliação do corpo do doador, avaliação biomicroscópica da morfologia do globo ocular e da córnea e contagem celular endotelial. RESULTADOS: De 1.116 córneas doadas no período, 518 (46,41% foram descartadas antes de serem preservadas, sendo 288 (25,80% devido à causa mortis, 56 (5,01% pelo histórico clínico do doador e 174 (15,59% pela avaliação do tecido. Das 598 córneas preservadas, 317 (28,40% foram destinadas ao transplante óptico e 168 (15,05% indicadas para transplantes tectônicos. CONCLUSÃO: A análise do prontuário hospitalar e história clínica do doador foi um importante fator de descarte de córneas antes da preservação. Já a avaliação biomicroscópica realizada na lâmpada de fenda é uma etapa fundamental para qualificação e classificação do tecido adequando-o para o paciente e garantindo um bom resultado cirúrgico.PURPOSE: To analyze causes of discarded donor corneas which were collected and preserved by São Paulo Hospital Eye Bank in a period of two years. METHODS: Retrospective study based in the investigation of donor's medical records, for clinical and ocular factors, age, death cause, serology results, body conditions, slit lamp corneal examination and endothelial cells counting. RESULTS: 1,116 corneas were donated and included in the study, 518 (46.41% were discarded before preservation, 168 (15.05% were not transplanted for optical purpose, but used for tectonic indication. The main reason of cornea discard was the cause of death in 288 (25.80% corneas, second the slit

  10. Study on penetration behavior of mitomycin in isolated cornea of rabbits%丝裂霉素在兔离体角膜中的渗透特性研究

    Institute of Scientific and Technical Information of China (English)

    王石健; 应苗法

    2014-01-01

    目的:考察丝裂霉素在兔离体角膜中的渗透特性。方法以谷胱甘肽缓冲液为接收液,使用水平式扩散仪考察丝裂霉素在离体兔角膜中的渗透特性;样品使用HPLC测定,采用Agilent Zorbax C18柱(150 mm ×4.6 mm,5μm),流动相为甲醇∶水(70∶30,v/v),流速为1 mL/min,检测波长为365 nm。结果建立的丝裂霉素HPLC测定方法专属性、线性、精密度等均良好,丝裂霉素在兔角膜中的渗透按照一级动力学拟合时相关系数最高。结论丝裂霉素在兔离体角膜中的渗透符合一级动力学过程。%Objective To investigate the penetration behavior of mitomycin in isolated cornea of rabbits. Methods The penetration behavior of mitomycin in isolated rabbit cornea was investigated on horizontal diffusion cells using glutathione buffer as receptor medium. The samples were determined by HPLC and separation was achieved on an Agilent Zorbax C18 column. The mobile phase consisted of methanol/water (70/30,v/v) and delivered at a flow rate of 1 mL/min. The detective wavelength was set at 365 nm. Results The established HPLC method had shown good selectivity,linearity and precision. The correlation index was the highest when the penetration profile of mitomycin in isolated rabbit cornea was fitted by first order kinetic equation. Conclusion The penetration behavior of mitomycin in isolated rabbit cornea accords to first order kinetics.

  11. Dendritic immune cell densities in the central cornea associated with soft contact lens types and lens care solution types: a pilot study

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    Sindt CW

    2012-03-01

    Full Text Available Christine W Sindt1, Trudy K Grout1, D Brice Critser1, Jami R Kern2, David L Meadows21University of Iowa Hospitals and Clinics, Iowa City, IA; 2Alcon Research Ltd, Fort Worth, TX, USABackground: The purpose of this study was to assess whether differences in central corneal dendritic immune cell densities associated with combinations of soft contact lenses and lens care solutions could be detected by in vivo confocal microscopy.Methods: Participants were adults naïve to contact lens wear (n = 10 or who wore soft contact lenses habitually on a daily-wear schedule (n = 38 or on a study-assigned schedule for 30 days with daily disposable silicone hydrogel lenses (n = 15. Central corneas were scanned using an in vivo confocal microscope. Cell densities were compared among groups by demographic parameters, lens materials, and lens care solutions (polyhexamethylene biguanide [PHMB], polyquaternium-1 and myristamidopropyl dimethylamine [PQ/MAPD], peroxide, or blister pack solution [for daily disposable lenses].Results: Among lens wearers, no associations were observed between immune cell densities and age, gender, or years of lens-wearing experience. Mean cell density was significantly lower (P < 0.01 in nonwearers (29 ± 23 cells/mm2, n = 10 than in lens wearers (64 ± 71 cells/mm2, n = 53. Mean cell density was lower (P = 0.21 with traditional polymer lenses (47 ± 44 cells/mm2, n = 12 than with silicone hydrogel lenses (69 ± 77 cells/mm2, n = 41. Lowest to highest mean density of immune cells among lens wearers was as follows: PQ/MAPD solution (49 ± 28 cells/mm2, blister pack solution (63 ± 81 cells/mm2, PHMB solution (66 ± 44 cells/mm2, and peroxide solution (85 ± 112 cells/mm2.Conclusion: In this pilot study, in vivo confocal microscopy was useful for detecting an elevated immune response associated with soft contact lenses, and for identifying lens-related and solution-related immune responses that merit further research.Keywords: Clear Care

  12. [The early post-operative wound healing mode study of the rabbit cornea after flap-free epiploic laser in-situ keratomileusis].

    Science.gov (United States)

    Liu, Xi; DU, Zhi-yu; Xiang, Yi-min; Huang, Zheng

    2009-10-01

    To evaluate the wound healing mode of rabbit corneal epithelium after Epi-LASIK(epiplolic laser in-situ keratomileusis) and Flap-free Epi-LASIK(Flap-free epiploic laser in-situ keratomileusis). Twenty-four New Zealand white rabbits (48 eyes) were randomly divided into four groups. There were six rabbits in every group, which were randomly treated with Epi-LASIK in one eye and Flap-free Epi-LASIK in the other by VISX20/20 excimer laser. Other three rabbits (6 eyes) without any treatment were used as control. The corneal epithelium wound healing mode was observed at 1, 2, 4, 7 days after surgery by light microscope and electron microscope. The number of keratocytes cells in the central anterior stroma were counted by hematoxylin-eosin-stained. The expression of basic fibroblast growth factor (bFGF) in corneal stroma were assessed by Immunohistochemistry staining. Cornea stromal cell apoptosis was evaluated by terminal deoxyribonuc-1-eotidyl transferase-mediated deoxynuridine triphosphate nick end labeling (TUNEL) assay.All the data was analysised by t-test to evaluate the different of wound healing mode after Epi-LASIK and Flap-free Epi-LASIK. The findings of light microscope and electron microscope investigation demonstrated that, at the first day after surgery, there was one layer of neogenesis of the corneal epithelial cells covering the area of surgery in Flap-free Epi-LASIK specimens. It would increase gradually after 7 days. At the first day after the surgery, the base membrane of the corneal epithelium was tightly attached to the stroma in Epi-LASIK specimens. At the second day after the surgery, there was edema observed on the epithelium flap in the Epi-LASIK specimens. There were more keratocytes cells found at 4 days after surgery in Flap-free Epi-LASIK group (33.85 +/- 3.39) than that in Epi-LASIK group (t = -2.315, P corneal wound healing.

  13. The cornea in systemic disease

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    W.D.H. Gillan

    2005-01-01

    Full Text Available Systemic  disease  often  results  in  corneal signs that are easily observable by means of bio-microscopy. Optometry is in a unique position to detect the corneal manifestations of systemic disease. This review presents corneal signs of various systemic diseases. The list is not com-plete but the review rather attempts to empha-size the importance of detection, and referral, of systemic diseases.

  14. Determination of posaconazole level in rabbit cornea by high performance liquid chromatography%高效液相色谱法测定兔角膜中泊沙康唑的含量

    Institute of Scientific and Technical Information of China (English)

    吴伟; 何梅凤; 钟建文; 郭泽莉

    2014-01-01

    OBJECTIVE To establish a high performance liquid chromatography method for the determination of content of posaconazole in rabbit cornea and explore the permeability of the posaconazole eye drops so as to provide theoretical basis for clinical use of this eye drops .METHODS The rabbit corneas were obtained and quantified at 30 minutes after topically applying posaconazole eye drops to the rabbit eyes .The drug levels were assayed by high performance liquid chromatography .The separation was performed on Diamonsil C18 column ,the mobile phase was acetonitrile‐water (60∶40) with the flow rate of 1 .0 ml/min ,the detection wavelength was at 262 nm and column temperature was 25℃ .RESULTS The chromatograms of HPLC showed that the posaconazole peak could be separated from other materials ,no interferential peak was seen .The calibration curve of posaconazole was linear within the concentration range of 0 .204 5‐4 .089 9 μg/ml ,r=0 .9999 .The recovery rate was more than 90 .0%and the relative standard deviations(RSD)of intra‐day and inter‐day assays were less than 3 .0% .The posaconazole concentration in cornea was (5 .9 ± 0 .4)μg/g .CONCLUSION The method is accurate and reliable ,which can be used for the determination of the content of posaconazole in rabbit cornea .The posaconazole content in cornea is higher than the minimal inhibitory concentration of most fungi .The posaconazole eye drops can be used as a topi‐cal antifungal agent to treat keratitis .%目的:建立兔角膜中泊沙康唑含量测定的高效液相色谱分析方法,探讨眼局部应用泊沙康唑滴眼液后在角膜中的吸收情况,为该滴眼液的临床应用提供理论依据。方法兔结膜囊内滴入泊沙康唑滴眼液,30 min 后取角膜,采用高效液相色谱法测定角膜中泊沙康唑的含量,色谱条件:采用 Diamonsil C18为色谱柱;流动相为乙腈∶水(60∶40),流速1.0 ml/min ,检测波长262 nm ,柱温25℃。结

  15. ESTUDO HISTOPATÓLOGICO NAS CÓRNEAS DOS CÃES TRATADOS COM 2-1 FOSFATO DISSÓDICO DE BETAMETASONA E FOSFATO DISSÓDICO/ACETATO DE DEXAMETASONA, QUE RECEBERAM TRASPLANTES COM CÓRNEAS DE SUÍNOS HISTOPHATOLOGICAL STUDY IN CORNEAS OF DOGS, TREATED WITH 2-1 DISSODIC FOSPHATE OF BETAMETHASONE AND DISSODIC FOSPHATED/ACETATE OF DEXAMETHASONE, THAT HAD RECEIVED IMPLANTATION OF SWINE CORNEAS

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    Luiz Antônio Franco da Silva

    2007-09-01

    Full Text Available

    Foram utilizados 10 cães, sem raça definida, com peso médio de 10kg, examinados e considerados sadios. Cada cão, a seu tempo, teve implantada no olho esquerdo córnea de suíno, conservada em câmara úmida pelo período máximo de seis horas. Cada animal antes da cirurgia recebeu 4 mg de fosfato dissódico/acetato de dexametasona, por via intramuscular, e uma gota de fosfato dissódico de betametasona/sulfato de gentamicina colírio. Conservou-se a medicação ocular 4 vezes/dia e a intramuscular semanalmente, até o sacrifício do cão. Cada qual foi sacrificado por processo indolor (thiopental sódico + cloreto de succinilcolina e teve o olho que recebeu implante com córnea de suíno enucleado. Foi injetado formol 10% na câmara do vítreo e a córnea foi removida com aba escleral, tratada e corada com hematoxilina-eosina. Foram analisadas as seguintes áreas: enxerto, áreas adjacentes receptoras e observadas as várias alterações.

    PALAVRAS-CHAVE: Histopatologia; corticosteróides; xenotransplantes; córnea; canino; suíno.

    Ten dogs, with no definitive breed, average weight of 10 kg, were in this research. After being examined and considered healthy they received numbers, from 11 to 20 in their collars. Each dog received implantation, in the left eye, of swine cornea, obtained at Casa de Banha Caçula, a slaughterhouse, and maintained in wet chamber for six hours at most. Before surgery, each animal received 4 mg of dissodic phosphate/acetate dexamethasone IM and, once a week one drop of dissodic phosphate betamethasone and gentamicin sulphate, four times a day, until the 28th day. when the animals were sacrificed through painless process (Thiopental sodic

  16. 部分环状板层角膜移植治疗蚕蚀性角膜溃疡%Clinical effect of using a ring-shaped donor cornea in partial lamellar keratoplasty for Mooren's ulcer

    Institute of Scientific and Technical Information of China (English)

    王秀先; 史伟云; 李素霞; 王婷; 高华

    2012-01-01

    Objective To evaluate the clinical effect of using a ring-shaped donor cornea in partial lamellar keratoplasty for early-stage Mooren's ulcer.Methods It was a retrospective case series study.Partial lamellar keratoplasty was performed on 11 eyes with Mooren's ulcer.The patients were treated for symptoms for a week or more.A residual ring-shaped section of a donor cornea was used after partial penetrating keratoplasty.A trephine (7.75-8.00 mm) was used to mark the central cornea.An ophthalmic knife was used to deepen the trephine groove to an extent dictated by the size of the lesion in order to excise the lesion adequately.If corneal perforation appeared before or during the operation,it was repaired using a very thin layer of lamellar cornea larger than the perforation and sutured to the perforation hole with 10-0 sutures.Then a ring-shaped donor graft was used to repair the lesion area.Visual acuity,condition of the lesion,and complications were monitored for 6-36 months.Repeated measures analysis of variance were used.Results Compared to pre-surgery,uncorrected visual acuity improved by a mean of 1.36±1.21 Snellen chart lines at 1 month,1.72±1.47 lines at 3 months and 1.86±2.04 lines at 6 months.Best spectacle-corrected visual acuity improved by a mean of 0.46±0.93 Snellen chart lines at 1 month,0.73±1.10 lines at 3 months and 1.55±1.75 lines at 6 months.There were significant difference before and after surgery at uncorrected visual acuity (F=5.630,P<0.05) and best spectacle-corrected visual acuity (F=5.925,P<0.05).One patient had graft epithelial defect and was cured with an amniotic membrane transplant after 20 days.One patient had a recurrence after 19 months and was cured with a second lamellar keratoplasty.No rejections were detected.Conclusion A ring-shaped donor cornea in partial lamellar keratoplasty for Mooren's ulcer is a useful option when medical treatment fails.It cannot only control the development of the disease,but also preserve the

  17. Study of irradiated drug-containing xeno-Cornea in treatment of ocular chemical burns%含药辐照异种角膜治疗眼化学烧伤的研究

    Institute of Scientific and Technical Information of China (English)

    肖长辉; 易敬林; 曾元临; 辛国华; 毛远桂; 李国辉

    2001-01-01

    Objective To investigate an ideal therapeutic method for ocular chemical burns. Methods 36 New Zealand white rabbits with eyes of hydrochioric acid burn or alkali burn were randomly divided into experiment group and control group. The eyes in experiment group were treated by irradiated drug containing Xeno - Cornea. Control group received routine therapy. 34 cases (52 eyes)with ocular chemical burns were randomly divided into treatment group and control group. The eyes were treated as animal group. Results The study showed that the rate of ocular infection, cornea ulcer and perforation in experiment group were obviously lower than those in control group (P<0.05). Clinical study showed that the cure rate in treatment group was obviously higher than that in control group(P<0.05) . Conclusion Being an ideal biological dressing materals, irradiated drug - containing xeno - cornea had well therapeutic effect on ocular chemical burns.%目的探索一种理想的眼化学烧伤治疗方法。方法动物实验和临床研究相结合。将36只酸、碱眼化学烧伤的新西兰白兔随机分为实验组和对照组,实验组应用含药辐照异种角膜治疗,对照组按常规治疗。将34例(52眼)眼化学烧伤患者随机分为治疗组和对照组,治疗方法同动物组。结果动物实验显示实验组眼感染率及角膜溃疡、穿孔率远低于对照组(P<0.05)。临床研究显示治疗组治愈率远高于对照组(P<0.05)。结论含药辐照异种角膜是一种理想的角膜覆盖材料,对眼化学烧伤具有良好的治疗效果。

  18. 眼球萎缩改良结膜瓣覆盖术临床观察%Clinical observation of non-orbital implantation with conjunctival flap covering the entire cornea for eyeball atrophy surgery

    Institute of Scientific and Technical Information of China (English)

    乔磊; 田艳明; 李鹏; 闫希冬

    2015-01-01

    Objective To investigate the clinical observation of non-movable coral eye-seat implantation with modified conjunctival-Tenon's capsule flap covering the entire cornea for eyeball atrophy surgery,applying thin eye model.Methods Thirteen eyes (13 light or moderate eyeball atrophy cases) who had accepted the surgical treatment including conjunctival flap covering the entire cornea,receiving thin eye-model 1 month later,which had satisfying cosmetically result.Results The surgical method of restoring mild and moderate atrophy eyeballs (especially mild atrophy eyeballs) to be the base and making a modified conjunctival-Tenon's capsule flap covering the entire cornea operation with thin eye-model fixed,restore the normally anatomy structure,had fewer complications and non-influence on eyeball movement.Conclusions The thin eye-model has good activity,satisfactory appearance and the appearance are obviously improved.%目的 探讨改良结膜瓣覆盖术治疗轻、中度萎缩眼球,术后安装薄型义眼模的临床效果.方法 对2006年1月至2014年1月在解放军第474医院就诊的13例(13只眼)轻、中度眼球萎缩患者保留完整角膜行结膜覆盖术,术后1个月配戴薄型义眼.结果 13例13只眼经过改良术式治疗配戴薄型义眼模,术后观察半年以上均达到满意的美容效果.结论 轻、中度萎缩眼球以其自身作为底座,行改良结膜瓣覆盖术并发症少,义眼模活动度良好,仿真效果逼真,明显改善患者容貌.

  19. 多西环素对碱烧伤大鼠角膜炎症细胞浸润的抑制作用%Doxycycline inhibits the infiltration of inflammatory cells in rat alkali burn corneas

    Institute of Scientific and Technical Information of China (English)

    赵静博; 邹文进; 付馨余

    2013-01-01

    AIM: To investigate the inhibited effect of Doxycycline on the infiltration of inflammatory cells in rat alkali burn corneas.METHODS: Corneas of 32 SD rats were injured with 1 mol/L NaOH, then divided into two groups: control and doxycycline - treated. All agents were administered topically 4 times daily. Slit - lamp microscope was performed and inflammatory index was calculated at 3, 7, 14 and 21 days after injury. Then 4 rats were randomly sacrificed and each cornea was divided into two parts, one for histopathology, the other for ICAM - 1 ELISA assay.RESULTS:ln control group, the inflammatory index and the number of inflammatory cell was higher than the doxycycline-treated dramatically at all time points ( P< 0.05). Compared with control group, corneal ICAM - 1 expression decreased significantly in doxycycline-treated group at all time points( P < 0.05).CONCLUSION: Doxycycline may inhibit inflammatory cell infiltration by down-regulating ICAM-1 expression.%目的:观察多西环素对碱烧伤大鼠角膜炎症细胞浸润的抑制作用.方法:健康SD大鼠32只,随机分为对照组、多西环素组,每组16只大鼠.建立角膜碱烧伤模型后,多西环素组予3g/L多西环素眼液点眼,对照组予眼液溶媒点眼.分别于碱烧伤后第3,7,14,21d观察计算炎症指数,角膜取材后进行病理切片及炎症细胞计数,行ICAM-1的ELISA检测.结果:多西环素组各时间点结膜充血、角膜水肿较对照组轻,炎症指数均明显低于对照组,差异有统计学意义(P< 0.05).多西环素组各时间点炎症细胞计数少于对照组(P< 0.05).多西环素组各时间点大鼠角膜的ICAM-1表达低于对照组(P<0.05).结论:多西环素可以抑制碱烧伤大鼠角膜的炎症细胞浸润,其机制可能是抑制ICAM-1的表达.

  20. Automatic Measurement of Central Cornea Thickness of Eye Anterior Segment Optical Coherence Tomography Image%眼前节光学相干层析图像中央角膜厚度自动测量

    Institute of Scientific and Technical Information of China (English)

    舒鹏; 孙延奎; 田小林

    2012-01-01

    为了自动获取所需医学参数,辅助医生诊断,提出了一种基于边缘检测和随机抽样一致性的中央角膜厚度自动测量方法.采用边缘检测算子获得眼前节组织光学相干层析图像中的初始边缘,然后利用随机抽样一致性算法对初始中央角膜上边缘进行圆弧拟合,进一步提取中央角膜下边缘并采用相同方法进行圆弧拟合,根据得到的中央角膜上下边缘计算中央角膜厚度.实验结果表明,该算法能排除图像中时常出现的中央亮线干扰,实时而准确地提取中央角膜上下边缘,得到的中央角膜厚度计算结果与人工分析基本一致,具有良好的应用价值和商业前景.%To obtain quantitative parameters automatically and help medical diagnosis, automatic measurement of central cornea thickness based on edge detection and random sample consensus (RANSAC) is employed. The initial edge in the eye anterior segment optical coherence tomography (OCT) image is obtained with an edge detector. Upper and lower edges of the central cornea are extraxted using the RANSAC circle fitting method. The central cornea thickness is then computed based on the edges. Experiments show that the proposed method can avoid the effect of light beam crossing, and good results comparable to manual analysis can be obtained in real time, indicating that the method has potential applications in the future.

  1. 农作物致角膜非穿透性外伤128例临床分析%The treatment analysis of 128 cases of nonpenetrated cornea trauma caused by crops

    Institute of Scientific and Technical Information of China (English)

    伍志琴; 聂尚武; 王金华; 黄辉; 苏凡凡

    2016-01-01

    目的 探讨农作物致角膜非穿透性外伤的正确治疗方法.方法 对128例农作物致角膜非穿透性外伤患者的临床资料进行回顾性分析.将患者按受伤至就诊时间分为三组:33例于受伤当天就诊(A组),72例于受伤次日至1周内就诊(B组),23例于受伤后1周就诊(C组).对三组患者的治疗方法及预后进行分析.结果 A组、B组、C组角膜溃疡发生率比较差异有统计学意义[6.1%(2/33)、62.5%(45/72)、100.0%(23/23),χ2=52.32,P<0.01].B组12例行球结膜遮盖术,2例行角膜移植术,2例行眼内容物剜除术;C组10例行球结膜遮盖术,4例行角膜移植术,2例行眼内容物剜除术.其余患者均经病灶清创联合药物治疗治愈.结论 农作物致角膜非穿透性外伤需重视并及时恰当处理,早期清创联合碘伏烧灼可有效预防感染性角膜炎的发生,球结膜遮盖术对角膜外伤后导致的角膜溃疡有较好的治疗效果.%Objective To investigate the clinical treatment of nonpenetrated cornea trauma caused by crops. Methods Clinical data of 128 cases of nonpenetrated cornea trauma caused by crops were retrospectively analyzed. According to the interval time between occurrence of trauma and clinic visiting, the patients were divided into 3 groups:group A (33 cases,<24 h), group B (72 cases, 24 h≤interval time<1 week) and group C (23 cases, ≥ 1 week). The therapeutic effects and prognosis were analyzed. Results There was statistical difference in the incidence of corneal ulcer among group A, group B and group C: 6.1% (2/33), 62.5% (45/72) and 100.0% (23/23), χ2= 52.32, P<0.01. In group B, 12 cases were treated with conjunctival flap covering, 2 cases received keratoplasty and 2 cases undertook enucleation. In group C, 10 cases were treated with conjunctival flap covering, 4 cases received keratoplasty and 2 patients undertook enucleation finally. All the other patients were cured with local debridement and medical treatment. Conclusions

  2. A clinical research of the cornea symmetry and refractive power of thyroid-associated ophthalmology disease%甲状腺相关眼病对角膜对称性及角膜屈光力的影响

    Institute of Scientific and Technical Information of China (English)

    余相均; 洪明胜; 余心洁; 陈捷灵; 张俐娜; 盛文; 毛剑波; 陈峰; 沈丽君

    2013-01-01

    目的 研究甲状腺相关眼病对角膜形态学及角膜屈光力的影响.方法 前瞻性病例对照研究.收集2012年12月至2013年5月在温州医科大学附属眼视光医院确诊为甲状腺相关眼病稳定期的患者24例(46眼)作为观察组,甲状腺相关眼病活动性的评估主要依据临床活动度评分CAS标准进行评估.收集与之年龄、性别相匹配的正常人30例(30眼)作为对照组.采用Pentacam测量2组角膜形态学参数及角膜屈光力,包括角膜表面变异指数(ISV)、垂直不对称指数(IVA)、高度不对称性指数(IHA)、高度离心指数(IHD)和最小曲率半径(Rim),角膜中央厚度(CCT),角膜前、后表面屈光力,角膜前、后表面散光度及散光轴向.应用眼球突出计(Hertel眼突计)测量观察组眼球突出度.用独立样本t检验或秩和检验对2组参数进行比较.结果 甲状腺相关眼病ISV中位数为21.0(10~71),高于正常组的14.0(10~34),Z=1.31,P<0.01;IVA为0.180(0.07~0.70),高于正常组的0.100 (0.50~0.37),Z=1.08,P<0.0I;IHA为5.95(0.0~28.7),高于正常组的1.65(0.2~13.9),Z=84.34,P<0.01;IHD为0.020±0.015,高于正常组的(0.010±.0040),t=5.67,P<0.01;Rim为(7.43±0.30)mm,低于正常组的(7.62±0.26)mm,t=-2.505,P<0.01;CCT为(523.74±26.00)μm,低于正常组的(546.25±28.84) μm,t=3.230,P<0.01;角膜前表面K1为(43.58±1.18)D,高于正常组的(42.86±1.43)D,t=2.123,P<0.05;角膜后表面K1为-6.20D(-7.2-5.7D),高于正常组的-6.10 D(-6.6~-5.7 D),Z=101.4,P<0.01;角膜前、后表面陡峭屈光力,角膜前、后表面散光轴向及大小与正常组相比差异无统计学意义.结论 甲状腺相关眼病能引起角膜对称性降低,角膜屈光力增加.%Objective To investigate the effect on cornea topographical characteristcs of thyroid-associated ophthalmology (TAO) disease.Methods In this prospective case control study,46 eyes of 24 patients diagnosed with the inactive TAO were recruited as study

  3. Color light-emitting diode reflection topography: validation of keratometric repeatability in a large sample of wide cylindrical-range corneas

    Directory of Open Access Journals (Sweden)

    Kanellopoulos AJ

    2015-02-01

    (0.02 to 12.13° for the keratoconic Group B, and 3.20±1.99° (0.17 to 8.61° for the cross-linked Group C. The control Group D had axis repeatability 2.16±1.39° (0.05 to 5.86°. The SAI index measurement repeatability was 0.33±0.40 (0.01 to 2.31 in the post-LASIK Group A, 0.39±0.75 (0.00 to 7.15 in the keratoconic Group B, and 0.43±0.56 (0.05 to 3.50 in the keratoconus post-CXL Group C. The control group had SAI measurement repeatability of 0.26±0.30 (0.00 to 2.39. The SRI index repeatability was 0.22±0.17 (0.01 to 0.96 for post-LASIK Group A, 0.20±0.18 (0.00 to 1.07 in keratoconic Group B, and 0.13±0.09 (0.00 to 0.45 in the keratoconus post-CXL Group C. The control Group D had SRI measurement repeatability of 0.23±0.16 (0.00 to 0.75.Conclusion: This novel corneal topography device appears to offer very high specificity in estimating corneal keratometry and specific corneal irregularity indices, even in topographically challenging corneas such as LASIK treated, keratoconic, and cross-linked.Keywords: LED topography, point-source topography, VU topographer, axis of astigmatism, Cassini topographer, steep meridian, surface regularity index, surface asymmetry index, form factor

  4. Transplantation of porcine type I atelocollagen into rabbit cornea%兔眼角膜去端肽猪皮Ⅰ型胶原膜移植的研究

    Institute of Scientific and Technical Information of China (English)

    王林妮; 戎慧丰; 颜华; 梁爽; 王鹏飞; 刘文广

    2011-01-01

    Objective To investigate corneal wound healing in rabbit after lamellar keratoplasty with porcine type I atelocollagen. Methods One hundred Chinese white rabbits, 80 rabbits were randomly divided into collagen materials group (group A) and allograft group (group B) , and group A and B were operated for the lamellar keratoplasty in one eye. Rest 20 rabbits'eyes (40 eyes) were used as the source of allograft for group B. After operation,the rabbits'eyes were observed by naked eyes and slit lamp, and recorded the score of the transparency and neovascularization of the cornea. The rabbits were sacrificed at 3rd, 14th day, the 1st, 3rd, and 6th month (each group eight eyes). The corneas were observed by histopathology, and the epithelial cells marker protein K3 were detected by immunohistochemistry. The results were analyzed by Rank sum test. Results The transparency of the cornea was increased gradually in A and B groups, and reached the peak on the 6th month(group A; x2 =31.250, P=0.000; group B: x2= 32.566, P = 0.000). The difference had not statistics significance in the comparison of the transparency from the 1st to 6th month(Z= -1.414, 0.000, -0.743;P=0. 157, 1.000, 0.458). The two groups had corneal neovascularization after 7 days, the intensity of corneal neovascularization in A group increased gradually, reached the peak on day 14, then decreased gradually (x2 = 20.727, P = 0.001); the intensity of corneal neovascularization in B group increased gradually, reached the peak on day 14, and then decreased gradually (x2 =25. 562, P =0. 000). The difference had statistics significance in the comparison of the neovascularzation of the cornea on the 6th month between A and B group(Z=-2.070,P=0.038).Histopathology showed the collagen material nearly disappeared after 1 month of surgery and arrangement of collagen tends to be regular.On the 6th month,arrayed collagen was regular in general,but disordered partly.Conclusions Porcine type I atelocollagen can promote

  5. Application of whole conjunctival fascia flap coveting cornea in plasty of trophic eyeball%结膜筋膜瓣覆盖角膜术在眼球萎缩整形中应用

    Institute of Scientific and Technical Information of China (English)

    任彦新; 马景学; 卫玉彩; 耿玉欣; 包永琴

    2014-01-01

    Objective To discuss a method and clinical effect of wearing thin ocular prosthesis after whole conjunctiva fascia flap covering operation.Methods A retrospective study.A total of 18 cases with mild-to-moderate eyeball atrophy compared exophthalmos with the other healthy eye that differed from 4 to 7 mm.According to the medical order,18 patients were divided into groups A and B.In the operation,the corneal epithelium and limbs epithelial tissue of atrophy eyeball were thoroughly removed,in which 10 cases (group A) the above the bulbar conjunctiva and fascia were slid downward,to cover the whole cornea and were fixed in the sclera below the limbs,and stratified suture was used in the below fascia and conjunctiva.Eight cases (group B),the above fascia conjunctiva and beneath fascia conjunctiva were stratified sutured and fixed in corneal central part.After a month,customized personalized ocular prosthesis was used,followed-up of 3 months to two years,to observe the curative effect.Results The conjunctiva fascia coverage of 10 patients in group A was good,with no corneal exposure and foreign body sensation,8 patients in group B,in which there was a horizontal crack in central cornea in two patients respectively,with foreign body sensation.The bilateral palpebral fissure height,orbital area plumpness and eye activity were similar in two groups,and the improved outward appearance was satisfactory,which reached the cosmetic effect Conclusions By apply complete conjunctiva fascia flap to cover cornea in mild-to-moderate eyeball atrophy,the healing of postoperative fascia and cornea is good,and the cornea is not easy exposed.With personalized ocular prosthesis,the cosmetic effect is good.%目的 探讨保留萎缩眼球配戴薄型义眼的方法和临床效果.方法 回顾性研究对2010年2月至2012年8月在河北医科大学第二医院眼科就诊的轻中度眼球萎缩患者18例(同健眼相比眼球突出度相差4~7 mm),按照就诊顺序分成A组(10

  6. MMP and TIMP in cornea alkaline burn after amniotic membrane transplantation in mice%碱烧伤小鼠行羊膜移植后MMP及TIMP表达的变化

    Institute of Scientific and Technical Information of China (English)

    朱晶; 程旭康

    2011-01-01

    目的:通过检测羊膜移植对小鼠角膜碱烧伤后不同时间点基质金属蛋白酶(metalloproteinases,MMP-2,8,9)及金属蛋白酶组织抑制剂(tissue inhibitor of metalloproteinases,TIMP-1,2)的表达,探讨羊膜移植在碱烧伤病程中所起的作用.方法:将40只Balb/c小鼠随机分为实验组和对照组,采用1mol/L氢氧化钠溶液烧伤小鼠角膜;实验组小鼠右眼行羊膜移植加睑裂缝合术,对照组仅行睑裂缝合术.分别在羊膜移植后的第0,2,7,14d处死小鼠,应用Western blot检测不同时间点MMP-2,8,9及TIMP-1,2的表达,增强化学发光法(enhanced chemiluminescent,ECL)对结果进行分析.结果:对照组角膜中MMP-2,8,9在第2d出现表达,第14d达到峰值,且表达主要位于基质层及上皮下的炎性细胞中.碱烧伤后第2d TIMP-1仅微弱表达,第7d可见表达增加,第14d到达峰值.TIMP-2第2d即可见表达增加,后持续增强.实验组各时间点MMP-2,8,9表达均低于对照组(P<0.01),TIMP-1,2的表达均高于对照组(P<0.01).结论:行羊膜移植可通过抑制MMP的表达,促进TIMP表达,从而抑制和延迟碱烧伤后角膜炎性浸润及溃疡的发生和发展,对碱烧伤后角膜的重塑起着重要作用.%AIM: To study metalloproteinases(MMP) and tissue inhibitors of metalloproteinases(TIMP) expresion in cornea of mice with alkaline burns treated with amniotic membrane transplantation (AMT), and to evaluate the effect of AMT in treatment of alkaline burns.METHODS: Forty Balb/c mice were divided into two groups (experimental group and control group) and their right eye corneas were burned with alkali(NaOH). The cornea was treated with AMT and secured with a tarsorrhaphy in experimental group, while the control group underwent tarsorrhaphy alone. At different time points(0, 2, 7, 14 days) after AMT, mice were killed and the expressions of MMP and TIMP in cornea were measured by the Western blot technique, and the results were analyzed by enhanced

  7. Injection of autogenous blood into the sealed space between cornea and amnion graft in treatment of epibulbar diseases%封闭式缝合羊膜空间自血留置在眼表疾病的应用

    Institute of Scientific and Technical Information of China (English)

    王作先; 宗酉明; 吴雅颖; 王毓琴; 张云忠; 万灵龙

    2003-01-01

    Aim To treat epibulbar diseases by injecting antogenous blood into the space produced by suturing an amnion graft overcornea. Methods The lesion tissue of the oeular surface was clewed under the microscope. Then, cornea and ocular conjunctiva werecovered with amnion which was running sutured with ocular conjunctiva. Autogenous blood was injected into the space resulted betweenthe amnion and the cornea and the blood was left to clot. Resultas Ninety-two patients were treated by this way, including 17 herpessimplex conjunctivitis, 9 bulbous keratitis, 2 corneal fistula, 3 comeal bums, 17 non-septic corneal ulcers, and 4 incision ulcers aftercornea grating. The irritation signs in all patients improved significantly and al1 gave pains disappeared after the operations. After theamnion was removed, comeal epithelial staining was negative. Seventy-nine patients acquired stable ocular surface. No case worsenedaggressively after treatment. Conclusion Autogenous blood injected into the space resulted by suturing the annion over the cornea iseffective to eliminate irritation signs and pain caused by epibulbar diseases and to heal the ocular surface in various epibulbar diseases.So, it can be widely used in clinic.%目的利用封闭式缝合的羊膜与角膜之间的空隙注入自血,留置形成血膜治疗眼表疾病.方法在手术显微镜下机械清除眼表病变组织后,羊膜遮盖角膜、球结膜,环型连续封闭式缝合在球结膜上,取自血注入羊膜与角膜之间,使之形成血膜.结果治疗单疱角膜炎1 7例、大疱性角膜炎9例、角膜瘘2例、重度电光性眼炎3例、酸性伤16例、碱性伤11例、热烧伤13例、非化脓性角膜溃疡17例、角膜移植创口溃疡4例,共计92例.术后明显刺激症状改善,术前难以忍受的疼痛全部消失.羊膜拆除后角膜上皮染色阴性,眼表面稳定达到79例占86%(79/92).因本法应用导致病情加重者为零.结论本法应用羊膜不是移植而是作为

  8. Expression of βig-h3 in keratoconus and normal cornea%βig-h3在圆锥角膜和正常角膜中的表达

    Institute of Scientific and Technical Information of China (English)

    赵桂秋; 王传富; 孙为荣; 张文卿; 李艳; 生晖; 梁涛

    2002-01-01

    Objectives To observe the expression of βig-h3 in normal cornea and keratoconus and to elucidate the role of extracellular matrix in keratoconus. Methods In situ hybridization was used to detect the expression of βig-h3 in the cornea. The cDNA library was screened with human βig-h3 cDNA probe to locate βig-h3 mRNA in cells. Results Expression of βig-h3 was found mainly in the stroma of the normal cornea and keratoconus, but decrease depending on the degree of keratopathy. In some serious cases, no expression signal was detected. The strongest expression was seen at the border of the normal region and keratoconus. Conclusions βig-h3,the structural component of the extracellular matrix, can affect cell adhensiveness in the development of corneal fibrous interstitial organization. During the development of keratoconus, decreasing levels of βig-h3 cause the diminution of corneal steadiness, which is related to formation of keratoconus.%目的观察圆锥角膜患者及正常人角膜组织中βig-h3的表达,探讨细胞外基质结构成分在圆锥角膜病变中的作用.方法采用原位杂交技术,以BIGH3基因的cDNA探针对圆锥角膜患者及正常人角膜组织中βig-h3mRNA进行细胞定位,检测角膜组织中βig-h3基因表达的水平.结果正常角膜组织中βig-h3表达主要在基质层;圆锥角膜患者βig-h3在基质层表达因角膜病变的程度不同而呈不同程度的减弱,严重者未检测到βig-h3的阳性表达信号.在圆锥角膜的正常和病变交界处,可见βig-h3表达呈强阳性.结论细胞外基质结构成分βig-h3在角膜纤维间质有序化的发育中起细胞粘附作用,在圆锥角膜病变的发生过程中 ,βig-h3的水平下降,导致角膜的稳固性下降,可能与圆锥角膜形成有关.

  9. Detection of basement membrane components on the surface of acellular porcine cornea%脱细胞猪角膜表面基底膜成分的检测

    Institute of Scientific and Technical Information of China (English)

    林旭初; 金岩; 惠延年

    2012-01-01

    BACKGROUND: The previous experiments have suggested that the acellular porcine cornea stroma (APCS) has a good compatibility and can support the growth of keratocytes and skin epithelial cellsOBJECTIVE:To detect whether the important structure for the grwth of corneal cells basement membrane canbe preserved on the surface of the APCSMETHODS: Fluorescent antibody was used to detect the basement membrane component (laminin and collagen IV) by immunohistochemistry Fluorescence microscopy was observed whether the basement membrane could be preserved on the surface oftheAPCS RESULTS AND CONCLUSION:Immunofluorescence staining showed that larnimn and collagen IV positively expressedthe APCS can preserve the natural basement membrane component of the cornea which is beneficial to the growth of comeal epithelial cells%背景:前期实验显示脱细胞猪角膜具有良好的组织相容性,可以支持角膜细胞和皮肤上皮细胞的生长.目的:检测脱细胞猪角膜是否保存了利于角膜上皮细胞生长的重要组织结构-基底膜.方法:利用荧光抗体对脱细胞猪角膜表面的基底膜成分(层粘蛋白和Ⅳ型胶原)进行免疫组织化学检测,荧光显微镜下观察脱细胞猪角膜表面是否保存了基底膜成分.结果与结论:免疫荧光染色显示脱细胞猪角膜前基质表面层粘蛋白和Ⅳ型胶原呈阳性表达,与新鲜猪角膜表面基底膜的荧光表达相同,表明脱细胞猪角膜保存了利于角膜上皮细胞生长的基底膜.

  10. Avaliação da qualidade das córneas doadoras em relação à idade do doador e causa do óbito Evaluation of the quality of donor corneas in relation to the age of donor and cause of death

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    Gleisson Rezende Pantaleão

    2009-10-01

    Full Text Available OBJETIVO: Analisar a qualidade das córneas avaliadas em lâmpada de fenda no Banco de Tecidos Oculares do Hospital de Clínicas da Universidade Federal do Paraná (BTO HC-UFPR relacionando com a idade e causa de óbito. MÉTODOS: Foram analisadas retrospectivamente fichas de avaliações padronizadas de 492 córneas, avaliadas no BTO HC-UFPR, do período de agosto de 2006 a agosto de 2008. Cada córnea avaliada foi classificada em relação a sua qualidade em: Muito bom, bom, regular e ruim; mediante os seguintes fatores: claridade da córnea, edema epitelial, defeito epitelial, edema estromal, dobras de Descemet, opacidade estromal, cicatrizes corneanas, densidade endotelial e guttata. RESULTADOS: A idade média dos doadores foi de 42,74 anos (dp=17,77. Dentre as causas de óbito, a mais comum foi trauma com 46,18%, seguindo por causas cardiovasculares com 41,86%. Na avaliação da córnea, foram classificadas: 57,11% como "bom", seguido por 20,73% "regular", 16,87% "muito bom" e 5,28% "ruim". Com aplicação de testes estatísticos baseados em modelo de regressão ordinal verificou-se que as córneas provenientes de mortes por traumas tendem a ser melhores, bem como aquelas de pacientes mais jovens. CONCLUSÕES: Estatisticamente, córneas de doadores mais jovens tendem a ter melhores graduações na avaliação, bem como córneas provenientes de doadores com morte por trauma tendem a ser de melhor qualidade quando comparadas com as provenientes de mortes por doenças cardiovasculares e outras doenças sistêmicas.PURPOSE: To analyze the quality of the corneas evaluated by slit lamp examination in the Eye Bank of the Hospital de Clínicas UFPR and its relation to donor age and cause of death. METHODS: Analysis of 492 corneas, evaluated in BTO HC-UFPR between August 2006 to August 2008. Each cornea was classified regarding the quality as: very good, good, regular and bad; and according to clarity, epithelial defect, stromal edema, Descemet

  11. Safety evaluation of rabbit corneas with subconjunctival injection of voriconazole%结膜下注射伏立康唑对兔眼角膜的安全性评价

    Institute of Scientific and Technical Information of China (English)

    闫瑾; 贾淑杰; 刘美欣; 韩泉洪; 张毅

    2015-01-01

    Objective To evaluate the safety of rabbit corneas with subconjunctival injection of voriconazole, and explore a safe range of antibiotic dose. Methods According to body weights, total 25 healthy rabbits were randomly divided into control group, and voriconazole (50, 100, 200, and 400μg) groups. The eyes of control group received subconjunctival injection of 0.1 mL balanced salt solution (BBS), and those treatment groups received 0.1 mL injection containing Voriconazole for injection 50, 100, 200, and 400μg, respectively. Every rabbit received five injections, once daily. Before the administration and 1, 7, and 14 d after the last injection, basic situations of the eyes were observed with slit lamp biomicroscopy and direct ophthalmscopy. Ultrastructures of the corneas were detected in vivo observation 1, 7, and 14 d after the last injection, respectively, and endothelial cell counts and corneal thicknesses were performed at the same time using confocal microscopy. Fourteen days after the last injection, pathological observations were carried out for corneal morphology. Results Subconjunctival injection of voriconazole in the rabbits at doses of 50 and 100μg, there was no abnormality in corneal cells, but at doses of 200 and 400μg, the rabbits showed edema cornea, exfoliation of corneal epithelium and abnormities in ultrastructures. However, there was no significant difference in endothelial cell counts and corneal thickness with those of control group at any time points. Conclusion It is safe for corneas of rabbit subconjunctival injection of voriconazole at the dose ≤100μg.%目的:评估结膜下注射伏立康唑对兔眼角膜的安全性,寻找兔眼结膜下注射伏立康唑的安全剂量。方法健康成年新西兰白兔25只,按体质量随机分为对照组、伏立康唑(50、100、200、400μg)组。对照组结膜下注射0.1 mL生理盐水,伏立康唑组均结膜下注射0.1 mL伏立康唑注射液,分别含50、100、200、400

  12. Perfil epidemiológico dos pacientes na lista de espera para transplante de córnea no Estado de Sergipe Epidemiological profile of the patients on the waiting list for cornea transplantation in the State of Sergipe , Brazil

    Directory of Open Access Journals (Sweden)

    Ângelo Augusto Araújo

    2004-08-01

    Full Text Available OBJETIVO: Avaliar o perfil epidemiológico dos pacientes em lista de espera e submetidos a transplante de córnea no estado de Sergipe e as principais indicações para este procedimento. MÉTODOS: Na Central de Transplantes de Sergipe, foram colhidos os dados de 320 pacientes que entraram em lista de espera e daqueles que tiveram a córnea transplantada entre maio de 2000 e novembro de 2002. Os dados registrados foram: doença corneana, a idade, o sexo, a acuidade visual e o tempo de espera na lista até a realização do transplante. RESULTADOS: A ceratopatia bolhosa do afácico e do pseudofácico foi a doença mais freqüente (39,1%, seguida por leucoma (22,5%, ceratocone (14,1%, "outras doenças" (10,6%, retransplante (7,8% e úlcera (5,6%. A idade média foi de 52,16 anos e não houve diferença significante entre os sexos. A acuidade visual mais freqüente foi visão de vultos e "percebe luz". Os 110 pacientes que tiveram a córnea transplantada esperaram, em média, seis meses. Os indicados por úlcera e por retransplante tiveram prioridade, aguardando menos tempo. Os portadores de ceratopatia bolhosa encontravam-se na faixa etária média de 68,5 anos e os com ceratocone, na de 23,6 anos. CONCLUSÕES: Pode-se concluir que a ceratopatia bolhosa é a principal indicação para transplante de córnea em nosso estado. Não há diferença entre a freqüência dos sexos; a idade média da doença mais freqüente está de acordo com seu aparecimento. A acuidade visual está dentro do esperado e o tempo em lista de espera é longo e inadequado.PURPOSE: To define the epidemiological aspects of the patients on the waiting list and those submitted to corneal transplantation in the state of Sergipe, Brazil and the main indications for this procedure. METHODS: The data of 320 patients who were on the waiting list and those who had their corneas transplanted from May 2000 to November 2002 were collected at the Transplantation Center of Sergipe. The

  13. Efeito do uso de lente escleral cosmética na sensibilidade tátil corneal em phthisis bulbi Effect of ocular prosthesis on cornea sensitivity in phthisis bulbi

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    Lucia Miriam Dumont Lucci

    2004-10-01

    Full Text Available OBJETIVOS: Comparar a sensibilidade tátil corneal entre olhos normais e aqueles com phthisis bulbi e avaliar as alterações provocadas na sensibilidade tátil corneal pelo uso de lente escleral cosmética em phthisis bulbi. MÉTODOS: Estudo prospectivo de 23 pacientes com phthisis bulbi unilateral. Foram realizadas medidas da sensibilidade tátil corneal em ambos os olhos utilizando-se o estesiômetro de Cochet-Bonnet antes e após 3 meses do uso da lente escleral cosmética. RESULTADOS: Em todos os pacientes, a medida da sensibilidade tátil corneal no olho com phthisis bulbi foi menor do que no contralateral (controle. Em 96% houve diminuição da sensibilidade tátil corneal após a adaptação da lente escleral cosmética. CONCLUSÃO: Após a adaptação da lente escleral cosmética, ocorre diminuição da sensibilidade tátil corneal nos olhos. A fisiopatologia é semelhante à encontrada nos usuários de lentes de contato.PURPOSE: To compare corneal sensitivity between normal eyes and those whith phthisis bulbi and also to analyze the alterations of corneal sensitivity in phthisis bulbi induced by wearing ocular prosthesis. METHODS: Prospective study of 23 patients with unilateral phthisis bulbi. Bilateral cornea sensitivity was evaluated using the Cochet-Bonnet esthesiometer before and after 3 months of wearing ocular prosthesis. RESULTS: In all patients, corneal sensitivity of the eye with phthisis bulbi was lower than that of the normal eye (control. In 96% there was decrease of corneal sensitivity after adaptation of ocular prosthesis. CONCLUSION: After wearing ocular prosthesis, there is a reduction in corneal sensitivity in phthisis bulbi. The pathophysiology seems to be the same as that found in contact lens wearers.

  14. Interferón alfa-2b tópico como primera opción en las neoplasias intraepiteliales corneoconjuntivales Topical interferon alfa-2b for primary treatment of conjunctiva-cornea intraepithelial neoplasia

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    M. Pérez de Arcelus

    2012-04-01

    Full Text Available Se describen dos casos de neoplasia intraepitlelial corneo-conjuntival (CIN tratados con interferón alfa-2b (IFN alfa-2b tópico como primera elección. El tratamiento clásico de los CIN ha sido tradicionalmente la resección completa con márgenes de seguridad seguida de crioterapia en el lecho quirúrgico. No obstante, y puesto que la tasa de recidivas puede alcanzar el 50% han sido propuestos coadyuvantes como la mitomicina C y el 5 fluoracilo, con el consiguiente riesgo de toxicidad corneal y límbica. El IFN alfa-2b presenta una eficacia similar a la cirugía en la erradicación completa de la masa tumoral como primera opción, con escasos efectos secundarios y nulo potencial carcinogénico, incluso en casos de recurrencia a terapia con mitomicina C, lesiones quirúrgicas residuales y formas difusas.We describe two cases of conjunctival-cornea intraepithelial neoplasia (CIN, treated with topical IFN alfa 2b. The traditional treatment for CIN is surgical excision usually with adjunctive cryotherapy. However, residual tumour may remain, which can lead to recurrence rates of more than 50%. 5-Fluorouracil, mitomicyn C and interferon alfa 2b are new pharmacological agents that have proved their efficacy in the treatment of CIN. As side effects are common, we present IFN alfa 2b as a single therapeutic agent as an effective and optimal treatment for presumed recurrent corneal and conjunctival intraepithelial neoplasia. It offers the benefits of topical therapy and avoids the risks of surgical or other interventions - specifically, ocular surface toxicity, cicatricial conjunctival changes, and limbal stem cell deficiency.

  15. 眼内麻醉剂对兔角膜内皮细胞影响的实验研究%Effect of intracameral anesthetics on rabbit cornea endothelium

    Institute of Scientific and Technical Information of China (English)

    马立威; 许军; 许明林; 张劲松

    2005-01-01

    目的:研究不同眼内麻醉剂对离体兔角膜内皮细胞的作用.方法:将实验用兔角膜取下后,分别用10g/L利多卡因、1g/L塞罗卡因及BSS处理.通过台盼蓝-茜素红联合染色观察兔角膜内皮细胞的形态学改变,并用计算机自动图像分析系统对兔角膜内皮细胞的损伤情况进行定量分析;对处理后的兔角膜内皮细胞进行扫描电镜观察,了解其超微形态学改变.结果:①各实验组中,10g/L利多卡因作用后兔角膜内皮细胞的损伤率分别为(0.91±0.12)%,(1.23±0.27)%,(2.42±0.31)%,(3.61±0.14)%;10g/L塞罗卡因作用后的兔角膜内皮细胞的损伤率分别为(0.68±0.16)%,(0.89±0.17)%,(1.84±0.34)%,(2.58±0.34)%.二者差异均具有显著性.(P<0.05,P<0.01).②眼内麻醉剂的作用时间与兔角膜内皮细胞的损伤率呈正相关,相关系数分别为0.974、0.976.③眼内麻醉剂作用后,10g/L利多卡因造成的兔角膜内皮细胞的损伤情况较10g/L塞罗卡因更为严重.结论:10g/L利多卡因及10g/L塞罗卡因都会对兔角膜内皮细胞造成损伤.比较而言,不含防腐剂的塞罗卡因更安全.%· AIM: To investigate the effects of different intraocular anesthetics on rabbit cornea endothelial cells in vitro.· METHODS: The excised rabbit corneae were treated with 10g/L lidocaine or 10g/L xylocaine for different durations. The morphological change was studied under a light microscope using dual staining of Typan-blue and Alizarine-red, and under a scanning electric microscope as well. The cornea endothelial cell (CEC) lost rate was calculated by computerized image analysis system.(Metamorph Image System V 4.6, Olympus Japan).· RESULTS: ①The CEC lost rate in 10g/L lidocaine groups for different durations was(0.91±0.12)%, (1.23±0.27)%, (2.42±0.31)% and (3.61±0.14)% respectively;while in 10g/L xylocaine groups was (0.68±0.16)%,(0.89±0.17)%, (1.84±0.34)% and (2.58±0.34)%, respectively. The difference was significant (P

  16. Dez anos de doação de córneas no Banco de Olhos do Hospital São Paulo: perfil dos doadores de 1996 a 2005 Ten years of corneal donation to the Hospital São Paulo Eye Bank: characteristics of cornea donors from 1996 to 2005

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    Consuelo Bueno Diniz Adán

    2008-04-01

    corneal tissue for transplant is still an important issue in Brazil. The Hospital São Paulo Eye Bank aims to provide high-quality ocular tissues for surgery starting with rigorous selection of donors. PURPOSE: To investigate the characteristics of cornea donors to the Hospital São Paulo Eye Bank during a 10-year period. METHODS: Retrospective analysis of Hospital São Paulo Eye Bank records from January 1996 to December 2005. RESULTADS: 3,624 corneas were evaluated by the Hospital São Paulo Eye Bank during this 10-year period. Mean age of donors was 56.8 years the highest proportion being in the 70-79 years age category. The most common cause of death was cardiovascular disease followed by cancer and trauma. Mean "enucleation" and "preservation" times were 3.8 and 3.6 hours, respectively. The number of corneas received by our eye bank from other eye banks decreased substantially whereas the number of corneas harvested by the Hospital São Paulo Eye Bank staff increased. Optisol GS® were the most utilized preservation media and a high proportion of corneas classified as "Excellent" or "Good" came from young donors. CONCLUSIONS: In a period of 10 years, there was a decreasing trend in the number of donated corneas provided by other eye banks to the Hospital São Paulo Eye Bank and an increase in the number of corneas harvested and processed by the Hospital São Paulo Eye Bank staff with a significant reduction of preservation time. Most donors were male and the main cause of death was cardiovascular disease. Although a great proportion of donated corneas came from older donors, the majority of corneas used for optical transplants came from younger ones.

  17. The ethical debate and countermeasures during cornea transplantation in China%我国开展角膜移植手术过程中存在的伦理争论探讨及对策

    Institute of Scientific and Technical Information of China (English)

    隋东明; 张晶晶

    2012-01-01

    OBJECTIVE To investigate the ethical debate and countenneasures during cornea transplantation in China. METHODS Attempted to explore bioethical issues from the relationship among donor, recipient and doctor, and analyzed its root causes, finally, put forward some suggestions how to avoid ethical risks in technology. RESULTS At present ethics argued mainly included: the donor faced the voluntary donation principle received the criticism and questioned, the donor families hoped to obtain some information corresponding receptors. Receptor faced that the heterogeneity transplantation caused the identity of acceptor's personality more complication. Doctor faced how grasping the death standard; donor and the relative whether knew the circumstances and both agree; how to unify both sides benefit of the donor and the acceptor. CONCLUSION According to the aspects of ethics controversy, we suggest: establishing some reasonable ethical principles and guidelines; establishing organ donor incentives; specification and construction of eye bank; establishing and strengthening mechanisms for monitoring the work of organ transplantation.%目的 探讨我国开展角膜移植手术过程中存在伦理争论及其解决措施.方法 从供体、受体、医生三者关系出发,探讨生命伦理问题,剖析其产生根源,并对如何规避生命科技发展中的伦理风险提出建议.结果 目前伦理争论主要包括:供体面临的伦理问题是自愿捐赠原则受到批评与置疑;供体家属希望获得相应受体的资料.受体面临的伦理问题是异种移植使受体人格同一性问题更加复杂化.医生面临的伦理问题是如何把握合理死亡标准;捐献者及其亲属是否知情同意;供体与受体双方利益如何统一.结论 根据目前存在的伦理争论,提出相应解决措施:建立合理的伦理规范原则;建立器官供体激励机制;规范和建设眼库;建立和加强对器官移植工作的监督机制.

  18. Calcareous degeneration of the canine cornea.

    Science.gov (United States)

    Sansom, Jane; Blunden, Tony

    2010-07-01

    The purpose of this paper is to describe a specific presentation of canine corneal calcification. Fourteen cases are described. In seven cases the corneal lesions were bilaterally symmetrical. In five cases the corneal lesion was unilateral. Two dogs were uniocular, the contralateral eye had been enucleated between 1 and 3 months previously by the referring veterinary surgeon following corneal ulceration and perforation. Of a total of 21 eyes with corneal calcification, 16 eyes had associated ulceration. The ulceration presented as follows: two eyes had descemetocoeles, four eyes had corneal perforations, eight eyes had stromal ulceration, and two eyes had superficial punctate ulceration. The cause of the corneal mineralization remains undetermined but underlying systemic disease, particularly hyperadrenocorticism (Cushing's Syndrome), is suspected as a possible contributing factor in some of these cases. Histopathology was carried out on three cases following a keratectomy and placement of a conjunctival pedicle flap into the ulcerated lesion.

  19. Facts about the Cornea and Corneal Disease

    Science.gov (United States)

    ... for surgery and recovery. The development of endothelial stem cell lines is an area of research being explored by a number of NEI-supported investigators. The goal of this research is to create stem cells that can be used as a laboratory model ...

  20. Silk film biomaterials for cornea tissue engineering.

    Science.gov (United States)

    Lawrence, Brian D; Marchant, Jeffrey K; Pindrus, Mariya A; Omenetto, Fiorenzo G; Kaplan, David L

    2009-03-01

    Biomaterials for corneal tissue engineering must demonstrate several critical features for potential utility in vivo, including transparency, mechanical integrity, biocompatibility and slow biodegradation. Silk film biomaterials were designed and characterized to meet these functional requirements. Silk protein films were used in a biomimetic approach to replicate corneal stromal tissue architecture. The films were 2 microm thick to emulate corneal collagen lamellae dimensions, and were surface patterned to guide cell alignment. To enhance trans-lamellar diffusion of nutrients and to promote cell-cell interaction, pores with 0.5-5.0 microm diameters were introduced into the silk films. Human and rabbit corneal fibroblast proliferation, alignment and corneal extracellular matrix expression on these films in both 2D and 3D cultures were demonstrated. The mechanical properties, optical clarity and surface patterned features of these films, combined with their ability to support corneal cell functions suggest that this new biomaterial system offers important potential benefits for corneal tissue regeneration.

  1. Laser assisted robotic surgery in cornea transplantation

    Science.gov (United States)

    Rossi, Francesca; Micheletti, Filippo; Magni, Giada; Pini, Roberto; Menabuoni, Luca; Leoni, Fabio; Magnani, Bernardo

    2017-03-01

    Robotic surgery is a reality in several surgical fields, such as in gastrointestinal surgery. In ophthalmic surgery the required high spatial precision is limiting the application of robotic system, and even if several attempts have been designed in the last 10 years, only some application in retinal surgery were tested in animal models. The combination of photonics and robotics can really open new frontiers in minimally invasive surgery, improving the precision, reducing tremor, amplifying scale of motion, and automating the procedure. In this manuscript we present the preliminary results in developing a vision guided robotic platform for laser-assisted anterior eye surgery. The robotic console is composed by a robotic arm equipped with an "end effector" designed to deliver laser light to the anterior corneal surface. The main intended application is for laser welding of corneal tissue in laser assisted penetrating keratoplasty and endothelial keratoplasty. The console is equipped with an integrated vision system. The experiment originates from a clear medical demand in order to improve the efficacy of different surgical procedures: when the prototype will be optimized, other surgical areas will be included in its application, such as neurosurgery, urology and spinal surgery.

  2. 复合水凝胶人工角膜裙边支架材料的生物相容性评价*%Biocompatibility of a hydrogel skirt scaffold in artificial cornea

    Institute of Scientific and Technical Information of China (English)

    邱岗峰; 石春芝; 周金生; 麦卫馨; 欧阳君君; 吴三强; 丘渭遥

    2013-01-01

    BACKGROUND: Beta-tricalcium phosphate/poly (vinyl alcohol) hydrogel (β-TCP/PVA-H) composite is a material with high water content, good softness, which is beneficial to the fibroblasts growth and col agen deposition. OBJECTIVE: To study the biocompatibility of β-TCP/PVA-H composite as an artificial cornea skirt material. METHODS: Delayed-type hypersensitivity: Both sides of the spinal skin of the guinea pig from beginning to end were injected with A solution (the mixture of complete Freund’s adjuvant and normal saline), B solution (extraction ofβ-TCP/PVA-H composite or normal saline or 2-Mercaptobenzothiazole), C solution (mixture of A and B solutions at equal volume), fol owed by local induction and inspire. The acute systemic toxicity test: Kunming mouse tail vein was injected with normal saline and β-TCP/PVA-H composite extraction. In vitro cytotoxicity assays: MRC-5 cells were cultured by β-TCP/PVA-H composite extraction, cel culture medium and phenol-containing cel culture medium. Intradermal reaction: The extracts of β-TCP/PVA-H composite, normal saline was injected intradermal y into the rabbit spine by normal saline (or sesame oil), normal saline and sesame oil. RESULTS AND CONCLUSION: The biocompatibility experiments of β-TCP/PVA-H composite showed that delayed-type hypersensitivity was graded 0-1, acute systemic toxicity test showed no symptoms, in vitro cytotoxicity was graded 0 or 1, and skin irritations were very slight. The experiments are agreed with the relative national standards, and β-TCP/PVA-H composite skirt as artificial cornea scaffold is a qualified medical material.%  背景:β-磷酸三钙/聚乙烯醇复合水凝胶具有高含水量、良好柔软性优点,有利于成纤细胞生长及胶原沉积,适用于做人工角膜裙边支架材料。目的:评价β-磷酸三钙/聚乙烯醇复合水凝胶人工角膜裙边支架材料的生物相容性。方法:①迟发型超敏反应:在豚鼠脊柱两侧

  3. EYE CLINICAL STUDY IN SWINE CORNEA IMPLANT DOGS TREATED WITH 2-1 BETAMETHASONE DISSODIC FOSPHATE AND DISSODIC FOSPHATED/ACETATE DEXAMETHASONE ESTUDO CLÍNICO NOS OLHOS DOS CÃES, TRATADOS COM 2-1 FOSFATO DISSÓDICO DE BETAMETASONA E FOSFATO DISSÓDICO/ACETATO DE DEXAMETASONA, QUE RECEBERAM IMPLANTES COM CÓRNEAS DE SUÍNOS

    Directory of Open Access Journals (Sweden)

    Nilo Sérgio Troncoso Chaves

    2007-09-01

    Full Text Available

    Ten mixed breed dogs, with a 10 kg average weight, were selected at Centro de Zoonoses de Goiânia. After being examined and considered healthy the dogs were enumerated from 11 to 20 on their collars. Each animal had swine cornea implanted into the left eye. The swine cornea was obtained at Casa de Banha Caçula, a slaughterhouse, and conserved in humid chamber for a maximum 6 hour period. Before surgery, each animal received 4 mg dissodic fosphate/acetate dexamethasone IM and was instilled one drop of betamethasone dissodic fosphate and one drop of gentamicin sulphate, maintaining the ocular medication 4 times/day and the intramuscular medication once a week, until euthanasia. After xenografts being realized, each cornea was examined every 7 days using direct ophthalmoscope to analyse transparency, vessels new formation, episcleral and conjunctival vessels reaction, cornea thickness, depth and presence or absence of deposits into the anterior chamber. On day 7 clinical evaluation, all cornea xenotransplant eyes (100% had lost transparency (++,+++, there was episcleral vessels reaction (P, anterior chamber depth was preserved (N, there wasn’t edema, as well as deposits (A on anterior chamber. On day 14, with the loss of two corneas by “self-trauma”, the other dogs had their implanted corneas (80% completely opaque (+++, with important ciliary reaction (P, edema (A; however, the anterior chamber integrity was preserved (N, without presence of deposits (A. With three more dogs euthanized between days 14 and 21, due to corticosteroids side-effects, the remaining dogs (50% preserved their implants with the day 14 alterations until the end of this experience.

    Foram utilizados 10 cães, sem ra

  4. 中期保存角膜远程投送包装系统温度控制的实验研究%An experimental study of the temperature controlling package system in transportation of cornea preserved with itermediate term medium

    Institute of Scientific and Technical Information of China (English)

    吴志勇; 蒋华

    2010-01-01

    Objective To invent a package system for transportation of cornea preserved in intermediate term medium,to study the effect of temperature controlling about the system,and to discuss the security of cornea and the feasibility of cornea transportation in the package system.Methods In normal condition,ice box and intermediate medium bottle were laid together in the incubator,of which were both 4℃C,with sponge stuffing the spare room.Divide into 4 groups by the cubage of the medium,and record the temperature curve both in-bottle and ex-bottle.Observe the maintaining time of the temperature between zoro and 4℃,and analyze among the groups.Compare the cornea position before and after imitated distance transportation in the package system.Results In normal condition and in a definite range of medium cubage,the package system Can maintain the temperature between zero and 4℃ for about 20h,which is much more longer than ice-bucket and the temperature rises smoothly.The cornea position was not changed after imitated transportation.Conclusion In normal condition,the package system Can control the temperature between zero and 4℃ effectively,and it is necessary to preserve cornea by intermediate term medium.The system can maintain this temperature range for more than 20h,and the time is enough for transportation to most of areas in the world.The package system also has the characteristics of vibration resisting and cornea immobility.It is secure for Intermediate term cornea preservation and feasible for long-distance transportation.%目的 探讨应用于角膜中期保存的安全性及远程投送的可行性.方法 常温下,将冰点为4℃冰盒与盛有4℃中期保存液的保存瓶,一同置于保温箱内,并用海绵固定.按照保存介质(中期保存液)体积分组,采用双通道温度记录仪,记录不同组别的瓶内瓶外温度变化曲线,观察该包装能否满足中期保存>0℃,≤4℃的温度要求,及该温度范围的维持时间,并在

  5. The study of the treatment of Modified conjunctival flap microsurgery to the cornea infective ulcer with perforation or nearly perforation%改良结膜瓣遮盖术治疗穿孔或近穿孔感染性角膜溃疡的探讨

    Institute of Scientific and Technical Information of China (English)

    吴洁; 龙潭; 朱海峰; 马挺; 杜蕊; 程燕; 梁厚成

    2008-01-01

    Objective To investigate the treatment of the modified conjunctival flap microsurgery (m-CFM) to the cornea infective ulcer with perforation or nearly perforation. Methods The m-CFMs were operated to the 12 patients with perforated cornea ulcer and 52 ones with nearly perforated ulcer. Before surgeries, it should be done as possible as we could to control the infection. Then while surgery, the ulcers were cleared, and the conjunctival flap and the Tennon's capsule were sew on the cornea to envelope the ulcer in file. Results Among the patients with nearly perforation, the infections in 47 eyes were controlled by one surgery, as the same time, the flaps on other 5 eyes were dissolved in 2 weeks (the second surgeries were done to the 3 eyes of them, and succeeded, and the other 2 were abandoned), the surgeries to 12 eyes with perforation were all succeed, though 3 of them catch a secondary glaucoma. Conclusions The m-CFM could be done when the infection of the cornea ulcer was be controlled, and that is so easy to operate that it could be done at the elementary hospital, especially could be done to shorten the cure circle and to protect the eyes when the cornea transplantation couldn't be done.%目的 探讨应用改良结膜瓣遮盖术治疗感染基本控制的穿孔或近穿孔的感染性角膜溃疡.方法 选择感染基本控制的角膜溃疡穿孔12例、近穿孔病例52例(共64只眼).手术中溃疡面修剪清创,4%碘酊烧灼溃疡面或边缘(穿孔者),在临近角膜溃疡处转移球结膜瓣,将Tenon囊组织单层或多层于创面修剪后间断固定缝合,再将已转移的球结膜瓣遮盖于表面间断固定缝合.结果 47只角膜溃疡近穿孔患眼于术后一次成功,术后2W内余5只眼结膜瓣溶解脱落(3例再次结膜瓣手术成功,2例放弃治疗)手术一次成功率92.19%.角膜溃疡穿孔患眼术后成功率达100%,但是有3只眼术后发生继发性青光眼.结论 改良结膜瓣遮盖手术在角膜溃疡感

  6. The efficaly of rotational autokeratoplasty combined with double-lamellar autokeratoplasty for the treatment of cornea perforation%自体角膜转位移植联合双板层角膜移植治疗角膜穿孔效果评价

    Institute of Scientific and Technical Information of China (English)

    姚晓明; 彭云; 黎明; 周晓萍

    2014-01-01

    Objective To evaluate the clinical efficacy of rotational autokeratoplasty combined with double-lamellar autokeratoplasty in the treatment of cornea perforation.Methods Eight patients (8 eyes) with cornea perforation who underwent rotational autokeratoplasty combined with double-lamellar autokeratoplasty from June 2010 to December 2012 were retrospectively reviewed.8 cases (8 eyes) with cornea perforation included 5 cases of fungal corneal ulcers with perforation,1 case of pseudomonas ulcer with perforation,1 case of advanced Mooren' s ulcer with perforation,and 1 case of acute perforation of keratoconus.All cases underwent rotational autokeratoplasty combined double-lamellar autokeratoplasty.Results After operation,all patients not only preserved their eyeballs,but also retained the best-corrected visual acuity at 1 month after surgery:hand move in 3 eyes,0.04 in 2 eyes,0.05 in 1 eye,0.08 in 1 eye,0.1 in 1 eye.In two weeks after operation,the grafts epithelium was integrity in 8 eyes.No other postoperative complications developed in all patients.Conclusion Rotational autokeratoplasty combined with double-lamellar autokeratoplasty is an effective method to save eyeballs under the situation of deficiency of cornea donor in the treatment of cornea perforation.%目的 评价自体角膜转位联合双板层角膜移植术治疗角膜穿孔的临床效果.方法 对2010年6月至2012年12月因角膜穿孔而实施自体角膜转位联合双板层角膜移植术的8例(8只眼)进行了回顾性分析.其中真菌性角膜溃疡穿孔5只眼,铜绿假单胞菌性角膜溃疡穿孔1只眼,角膜Mooren溃疡穿孔1只眼,圆锥角膜急性穿孔1只眼.结果 所有患者眼表形态结构均得到有效的恢复,避免了摘除眼球,5只眼保留了有效视力,其中术后1个月矫正视力:手动3只眼,0.04者2只眼,0.05者1只眼,0.08者1只眼,0.1者1只眼.术后14 d内8只眼角膜植片上皮均愈合完整,角膜植片与植床对合好.所有患者术后

  7. 手术切口大小对白内障术后视力和角膜的影响%The influence of operation incision size on postoperative visual acuity and cornea in cataract patients

    Institute of Scientific and Technical Information of China (English)

    江晓琴; 蔡方荣

    2012-01-01

      目的研究手术切口大小对白内障术后视力和角膜的影响.方法将患者分成A、B两个组后,均使用卡尔•蔡司手术显微镜(Carl Zeiss Stativ S88)和美国爱尔康白内障超声乳化仪(Alcon Infiniti Vision System),分别对两组患者进行3.5毫米透明角膜切口和6毫米反眉弓形巩膜隧道切口白内障超声乳化术628眼和336眼,然后用多美Tomey角膜地形图仪TMS-4对患者角膜形态参数进行计算分析.结果 A、B两组患者在术后7天时角膜散光度有较明显差异,3.5毫米角膜组于术后30天起无明显差异,6毫米巩膜组于术后90天才没有明显差异.术后30天,角膜组的散光度数低于巩膜组散光度数.术后7天角膜组SRI值要明显低于巩膜组,而SAI值却无组间差异.两组术后7天时,SAI及SRI值均高于术前水平,90天时恢复至术前水平.结论实施3.5毫米透明角膜切口超声乳化术效果较好,术后患者视力和散光恢复较快,角膜形态改变较小.%  Objective:To study the influence of operation incision size on postoperative visual acuity and cornea in cataract patients. METHODS:The patients were divided into A and B groups, using Carle Zeiss Stativ S88 operation microscope and American Alcon Infiniti Vision System, respectively for the two groups of patients by 3.5mm clear corneal incision and 6mm anti superciliary arch sclera tunnel incision phacoemulsification in 628 eyes and 336 eyes, and then use Tomey TMS-4 in patients with corneal topography corneal morphology parameters were calculated and analyzed. RESULTS:7 days later,A and B two group patients’s corneal astigmatism are obviously different, 3.5 mm corneal group on the 30 postoperative day without obvious difference, 6 mm scleral group from postoperative 90 days did not differ significantly. 30 days later, the degree of astigmatism corneal group below the scleral group astigmatism. 7 days later , corneal group’s SRI value was lower than the scleral

  8. Estudo de potenciais doadores de córnea no Hospital de Clínicas da UFPR Study of cornea potential donors at the Clinical Hospital of UFPR

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    Glauco Henrique Reggiani Mello

    2010-10-01

    Full Text Available OBJETIVO: Quantificar os potenciais doadores de córnea nas diferentes unidades hospitalares do Hospital de Clínicas da Universidade Federal do Paraná - UFPR. MÉTODOS: Foram analisados 369 prontuários de pacientes que foram a óbito nos meses de abril a julho de 2005 no HC-UFPR. No prontuário de cada paciente foram avaliados: evolução clínica, CID-10 e unidade hospitalar do óbito. Para ser considerado potencial doador (PD utilizou-se como critérios de exclusão os tópicos citados no Manual de Transplantes (2ª edição - 2004 da Secretaria Estadual da Saúde do Estado do Paraná. Os PD foram agrupados em: data do óbito, tipo de internamento e unidade hospitalar. Analisamos a quantidade de PD e total de óbitos. RESULTADOS: Dos 369 prontuários analisados, foram considerados potenciais doadores (PD 70 pacientes (18,97% do total de prontuários analisados As unidades: Centro de Terapia Intensiva, Centro de Terapia Semi e Pronto Atendimento Adulto foram responsáveis por 62,8% dos PD. Já a Neurocirurgia, Emergência Cárdio e UTI Cirurgia Cardíaca apresentaram uma relação de PD por óbito superior a 60%. CONCLUSÃO: Nesse estudo constatou-se que tanto as unidades com grande número de PD como aquelas com uma grande relação PD por óbito são locais de escolha para uma intervenção com o intuito de aumentar o número de doações em nosso meio.PURPOSE: To quantify the potential cornea donor from the different units of Clinical Hospital of the UFPR. METHODS: 369 records of patients who died from april until july of 2005 in the HC-UFPR were analyzed. The medical records of each patient had been evaluated: the clinical evolution, CID-10 and hospital unit of the death. To be considered potential donor (PD it was used as exclusion criteria the topics cited in the Manual of Transplants (2ª edition-2004 of the State Secretariat of the Health of the State of the Paraná. The PD had been grouped in: date of the death, type of internment

  9. 改良甘油冷冻保存角膜用于桥式穿透性角膜移植效果观察%The effect of the bridge-type penetration keratoplasty using the corneas preserved by improved long-term cryopreservation with glycerol

    Institute of Scientific and Technical Information of China (English)

    范军华; 李学喜; 潘栋平

    2012-01-01

    Objective To study the clinical effects of bridge-type penetration keratoplasty (BPK) using glycerol cryopreserved corneas for severe corneal perforation in the absence of fresh donor cornea for penetrating keratoplasty. Methods Ten patients (10 eyes) of severe corneal ulcer with perforation were received bridge-type penetrating keratoplasty with corneas preserved for 2 months to 2 years by improved cryopreservation with glycerol.The diameter of all corneal ulcers were 5-8mm,the diameter of perforations were 2-4mm.The transparency of the grafts,corneal epithelial healing time,intraocular pressure (IOP) and complications were observed after operation. Results The postoperative follow-up of 12 months to 2 years revealed that all corneal ulcers had no recurrence,grafts were translucent,comeal epithelium was fully restored in 10.2±3.6 days,graft edema dissipated in 30.7±6.8 days,IOP were all normal.The vision ranged from finger counting to 0.25. Conclusions In the absence of fresh donor comea,the operation of bridge-type penetration keratoplasty can be used successfully with the corneas preserved by improved long-term cryopreservation with glycerol in the clinical emergency treatment for severe corneal ulcer perforation.The grafts can keep transparency in a long time,so that it can keep the eyes to avoid enucleation and can enhance visual acuity.%目的 探索在没有新鲜供体角膜供穿透性角膜移植的情况下,观察以改良甘油长期冷冻保存的角膜行桥式穿透性角膜移植的效果.方法 角膜大面积溃疡并穿孔病例共10例10只眼,溃疡直径5~8 mm,穿孔直径2~4 mm.以改良甘油冷冻保存法保存2个月至2年的角膜进行桥式穿透性角膜移植,术后观察植片透明情况、角膜上皮愈合时间、眼压及并发症等.结果 术后随访12~24个月,10例患者溃疡均治愈无复发,植片呈半透明状,角膜植片上皮完全修复时间(10.2±3.6)d,植片水肿完全消退时间(30.7±6.8)d,眼压

  10. Método para o estudo in vivo da angiogênese: indução de neovascularização na córnea de coelho Method for in vivo study of angiogenesis: induction of neovascularization in the rabbit cornea

    Directory of Open Access Journals (Sweden)

    Raimundo P. González

    2000-09-01

    Full Text Available A angiogênese é um processo de múltiplos degraus que conduz a formação de novos vasos sangüíneos a partir de capilares preexistentes e que participa em diversos processos fisiológicos e patológicos incluindo o crescimento tumoral e de metástases. Vários métodos têm sido desenvolvidos para estudar a angiogênese. A técnica de indução de vascularização na córnea do coelho foi uma das primeiras a serem desenvolvidas pelo grupo de Gimbrone e colaboradores. O principal objetivo deste trabalho foi descrever a técnica de indução de angiogênese na córnea do coelho, através do implante cirúrgico de "pellets" de polimetilmetacrilato (PMMA contendo fator básico de crescimento fibroblástico (FCFb. Um "pellet" contendo 0.1 mig de FCFb foi implantado em uma das córneas e outro, sem FCFb, na córnea contralateral, como controle. A atividade angiogênica foi expressa por um índice, resultado da contagem do número de vasos e da medição de seu comprimento em milímetros. Os resultados mostraram que o FCFb induz crescimento vascular significativo a partir do sexto dia após o implante do "pellet" com atividade máxima no 15º dia. O PMMA sem FCFb não estimulou significativamente a vascularização. Esta técnica fornece uma nova opção de modelo para o estudo da biologia da angiogênese e para avaliação de drogas antiangiogênicas, usando "pellets" de polimetilmetacrilato (PMMA.Angiogenesis is a multi-step process that leads to the formation of new blood vessels from preexisting capillaries and is a key event in several physiological and pathophysiological processes including the tumor growth and development of metastases. Several in vitro and in vivo techniques have been developed for studying angiogenesis. The Rabbit Cornea Assay was one of the first, created by Gimbrone and coworkers. The main objective of this work was to describe the method of inducing angiogenesis in the rabbit cornea, by means of surgical

  11. A study on the effect of different residual stroma thicknesses on the rabbit cornea after laser in situ keratomileusis%不同角膜切削深度的准分子激光原位角膜磨镶术对兔角膜的影响

    Institute of Scientific and Technical Information of China (English)

    贺瑞; 周迎霞; 陈维毅; 王晓君; 冯熠; 渠敏; 刘斌; 赵炬伟

    2010-01-01

    目的 比较不同切削量的准分子激光原位角膜磨镶术(LASIK)术后眼角膜生物力学特性及角膜变形的情况.方法 选取成年新西兰白兔16只(32眼)随机分成A、B、C、D四个组.A、B、C组均行LASIK手术,使残留的基质床厚度分别为全层角膜厚度的30%、50%、70%;D组不行切削手术,作为对照组.术后6个月对兔眼行角膜地形图检查;对条状角膜在Instron试验机上进行单向拉伸和拉伸蠕变实验,用最小二乘法拟合得出不同切削量的角膜在蠕变实验中的弹性系数.结果 术后6个月,角膜地形图检测结果显示,A组角膜切削区的中央部较周边膨隆;B、C组均未发现角膜膨隆和圆锥角膜.与对照组比较,A、B组LASIK术后角膜的弹性模量有统计学意义(P0.05). Conclusion Stiffness coefficients diminished with an increase in the depth of the incision and the anti-tensile ability of the corneas is also reduced after LASIK. Further study needs to be done on keratoconus after LASIK with a residual stroma thickness of 50% of the cornea.

  12. 冰冻保存供体的周边深板层角膜移植治疗Terrien’s角膜变性的临床疗效%Peripheral deep anterior lamellar keratoplasty using a cryopreserved donor cornea for Terrien’s marginal degeneration

    Institute of Scientific and Technical Information of China (English)

    Dan HUANG; Wen-ya QIU; Bei ZHANG; Bing-hong WANG; Yu-feng YAO‡

    2014-01-01

    Objective: To evaluate the clinical efficacy of peripheral deep anterior lamellar keratoplasty (DALK) using a cryopreserved donor cornea for Terrien’s marginal degeneration (TMD). Methods: Thirty-one eyes of 27 patients with TMD underwent peripheral DALK using cryopreserved donor corneas. According to the distance between the inner edge of the lesion and the limbus, a ring-shaped or D-shaped DALK was performed. Al grafts were stored at−20 °C. Cryopreserved corneoscleral rims were prepared for ring-shaped grafts and cryopreserved whole eyebals were prepared for D-shaped grafts. The general conditions, intraoperative performance, postoperative corneal reconstruc-tion, astigmatism, best corrected visual acuity (BCVA), and various complications were analyzed. Results: Ring-shaped DALK was performed in 28 eyes and D-shaped DALK was performed in 3 eyes. Postoperative folow-up time was (28.4±24.8) months. There was evidence of inflammation before surgery in 12 eyes (38.7%) and intraoper-ative perforation occurred in 13 eyes (41.9%). The corneal structures of al eyes were reconstructed. Postoperative astigmatism and BCVA showed improvement (bothP=0.00) except for cases that underwent D-shaped DALK. Ten eyes (32.2%) developed transient ocular hypertension and one eye (3.2%) developed secondary glaucoma. No pri-mary disease recurrence or corneal allograft rejection was observed. Conclusions: Peripheral DALK for TMD using cryopreserved donor tissue is an effective technique that eliminates rejection and extends the use of donor eyes. Inflammatory history or intraoperative perforation has no adverse effect on graft recovery. However, D-shaped DALK did not achieve good visual outcomes.

  13. 不同光源共焦显微镜的活体正常角膜图像研究%The in vivo study of different light sources confocal microscopy in normal cornea

    Institute of Scientific and Technical Information of China (English)

    黎明; 姚晓明; 林跃生; 于莉; 林宝涛; 张醇; 聂丹瑶

    2012-01-01

    Objective To observe the different organizational structures of corneal layers of normal Chinese adult by halogen light source confocal microscopy and laser light source confocal microscopy in vivo,to study and compare its image features.Methods The central parts of the cornea were examined by halogen light source confocal microscopy and laser light source confocal microscopy from 35 cases (70 eyes) adult (age from 18 to 55 years old).The image characteristics of organizational structures of different corneal layers were studied and compared.Results The corneal epithelial wing-like cell layer images of 67 eyes (95.7%) were successfully examined.The basal epithelium,Bowman's membrane,anterior stroma,posterior stroma,Dscemet's membrane,endothelium were successful examined 100%.Conclusions The magnification of halogen light confocal microscopy are 1000 times,and the better magnification of cells.It's similar to the magnification of the primary electron microscopy.Because of the weak tissue penetration of the halogen light source and easy to decay,the cell images of different corneal layers of halogen light confocal microscopy are more blurred than laser corneal confocal microscopy,and the color of that are more gray,the structure of that are partial fuzzy; The magnification of laser corneal confocal microscopy are 800 times,cell magnification of that are slightly smaller than that of halogen light confocal microscopy.The cell images of different corneal layers of laser corneal confocal microscopy are more clearly than that of halogen light confocal microscopy,because of the stronger tissue penetration of the laser light source.And the very similar to the corneal tissue pathology slice images are available at a particular point of view.%目的 分别采用卤素灯光源共焦显微镜和激光光源共焦显微镜对中国正常成人活体角膜各层组织结构进行观察,对照研究其图像特征.方法 对35例(70只眼)中国成人(年龄18~55岁)中

  14. 白细胞介素-9在单纯疱疹病毒性角膜基质炎小鼠角膜组织中的表达%Expression of interleukin-9 in murine cornea with herpetic stromal keratitis

    Institute of Scientific and Technical Information of China (English)

    孙超; 夏丽坤

    2013-01-01

    Background Herpetic stromal keratitis (HSK) is an immunopathologic eye disorder mediated by CD4+ T lymphocytes.Interleukin-9 (IL-9) is a cytokine linked to the process of many immune inflammatory diseases,but whether IL-9 is involved in the immunopathology of HSK remains unclear.Objective This study was to investigate the expression of IL-9 in murine cornea during the development of HSK and its relationship with the degree of HSK.Methods One hundred and eighty clean BALB/c mice were divided into the normal control group (20 mice) and experimental group (160 mice).HSK models were established by scratching on the surface of the cornea followed by inoculation of 1 × 106 plague forming unit(PFU) herpes simplex virus type 1 (HSV-1) KOS strain.Change of ocular surface was examined under the slit lamp biomicroscopy before and I day,3,5,7,8,10,14,21 days after inoculation of HSV-1.The corneas of mice were collected on the time points mentioned above.The relative expression level of IL-9 mRNA in the cornea of mice was detected by real-time PCR.Immunocytochemical localization of IL-9 protein in murine cornea was viewed by a confocal microscope after preparation of the corneal cryostat sections.All experimental manipulations were undertaken in accordance with the institutional guidelines for the care and use of laboratory animals.Results Punctiform,dendriform or geographic defect in corneal epithelium were seen 3 days and healing 6 days after inoculation of HSV-1.However,edema and opacity of the corneal stroma appeared 7 days and peaked 14 days following the inoculation.Real-time PCR assay showed that very little of IL-9 mRNA (A260/A280) was expressed in the cornea in the mice of the control group.But in 1 day,3,5,7,8,10 and 14 days,the relative level of IL-9 mRNA was 6.37±0.45,5.66±0.53,3.93±0.35,3.62±0.34,3.23±0.18,2.57±0.14,2.19±0.20,with a significant difference among the various time points (F=92.764,P=0.000),and IL-9 mRNA in 1 day,3,5,7,8,10 and 14 days after

  15. ESTUDO DO LEUCOGRAMA COMO MONITOR DO 2-1 FOSFATO DISSÓDICO DE BETAMETASONA DO FOSFATO DISSÓDICO/ACETATO DE DEXAMETASONA, EM CÃES QUE RECEBERAM TRANSPLANTES COM CÓRNEAS DE SUÍNOS WHITE BLOOD COUNT AS A 2-1 BETAMETHASONE DISSODIC FOSFHATE AND DEXAMETHASONE DISSODIC FOSPHATE/ACETATE MONITOR IN SWINE CORNEA TRANSPLANTED DOGS

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    Larissa Franco de Araújo

    2007-09-01

    . Each animal had swine cornea implanted into the left eye. The swine cornea was obtained at Casa de Banha Caçula, a slaughterhouse, and conserved in a humid chamber during a maximum 6 hour period. Each animal received 4 mg dissodic fosphate/acetate dexamethasone IM and was instilled one drop of gentamycin sulphate/betametbasone dissodic fosphate, maintaining ocular medication 4 times/day and intramuscular medication once a week until euthanasia. Each animal had blood samples collected on day 0, before surgery, and on day 14 and 28 to analyse white blood count as a monitor of corticosteroids, imunocellular supressor drugs. From ten blood samples collected on day 0, 80% didn’t present any alterations, 10% presented leukocytosis with neutrophilia and 10% weren’t submitted to analysis. Due to the fact that three animals had been euthanized between days 14 and 21, these samples (40%, were analyzed and compared with these collected on day 0. Five animals (50% had their samples examined on day 28. On both days 14 and 28, there were 100% neutrophilia, 100% eosinophilia and 44.4% lymphocytopenia, indicating imunocellular supression.

    KEY-WORDS: Corticosteroids; xenotransplants; cornea; canine; swine.

  16. Effects of mitomycin C on infiltration of polymorphonuclear leukocytes after epithelial scrape injury in the mouse cornea Efeito da mitomicina C na infiltração de leucócitos polimorfonucleares após lesão epitelial em córnea de camundongo

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    Ana Cecília Souza Leão Escarião

    2008-12-01

    Full Text Available PURPOSE: To determine whether mitomycin C (MMC alters appearance and disappearance of polymorphonuclear leucocytes (PMN in the cornea stroma, using an epithelial scrape injury in eye mouse model. METHODS: Twenty-mice underwent mechanical epithelium debridement in the central cornea using 20% ethanol. After the scrape, the right eye received 0.02% MMC for one minute, while the left eye received physiological saline. The animals were sacrificed on days 1, 2, 5, and 14 after surgery, and corneal whole mounts were prepared for histology. PMN distribution was analyzed in digitized microscope images. Cell division in the cornea was determined by immunohistochemical detection of bromodeoxyuridine (BrdU, which was injected intraperitoneally before the mice were sacrificed. RESULTS: Epithelial scrape injury triggered infiltration of PMNs into the corneal stroma. An analysis of PMN distribution revealed that there was no difference between eyes treated with and without MMC at all time points. BrdU labeling showed that 0.02% MMC for one minute blocked keratocyte proliferation completely. CONCLUSION: MMC treatment regimen, which is common in clinical practice, inhibits keratocyte proliferation during wound healing, but when used at 0.02% for one minute, it does not affect PMN infiltration into the corneal stroma, and subsequent movement toward the injury site, or the disappearance of PMNs from the stroma, in the mouse epithelial injury model.OBJETIVO: O objetivo do estudo foi determinar se a mitomicina C (MMC altera o aparecimento dos leucócitos polimorfonucleares (PMN no estroma corneano após abrasão epitelial central, utilizando olhos de camundongo como modelo. MÉTODOS: Vinte camundongos foram submetidos à abrasão epitelial em córnea central utilizando etanol a 20%. Após a lesão, o olho direito recebeu MMC a 0,02% por 1 minuto, enquanto o olho esquerdo recebeu solução salina. Os animais foram sacrificados em 1, 2, 5 e 14 dias após a cirurgia e

  17. 温度敏感型富血小板血浆凝胶对兔角膜碱烧伤组织的修复效果%Thermo-Sensitive Platelet-Rich Plasma GelforRepair of Alkali-Burned Cornea in Rabbits

    Institute of Scientific and Technical Information of China (English)

    彭小维; 林森

    2016-01-01

    目的:观察温度敏感型富血小板血浆凝胶对兔角膜碱烧伤组织的修复效果,探讨角膜损伤修复的有效治疗方法。方法将20只白兔制作兔角膜碱烧伤模型后按随机数字表法分为 A、B、C、D 组,每组5只,分别采用生理盐水、自体富血小板血浆、温度敏感型富血小板血浆凝胶和凝胶空白基质点眼。于治疗前及治疗后3、5、7、10、14 d采用 Ando 和 Trousdale 标准对角膜炎症及溃疡评分,HE 染色观察角膜组织病理变化。结果治疗14 d 后 A 组与 D 组角膜炎症及溃疡评分差异均无统计学意义(P >0.05);B、C 组角膜炎症及溃疡评分较 A、D 组显著降低(P <0.01),且 C 组角膜炎症及溃疡评分较 B 组显著降低(P <0.01)。病理所见给药后14 d A 组和 D 组角膜处于炎症和溃疡期,B 组角膜处于修复中期,C 组角膜处于修复后期。结论温度敏感型富血小板血浆凝胶对兔角膜碱烧伤组织的修复效果良好,是一种有效的眼表修复制剂。%ABSTRACT:Objective Objective To observe the efficacy of thermo-sensitive platelet-rich plas-magel in therepair of alkali-burned rabbit cornea,and to investigate the effective methods for trea-ting corneal injury.Methods Corneal alkali burn was induced in 20 white rabbits.These model rabbits were topically administered normal saline (group A,n=5),autologous platelet-rich plas-ma (group B,n=5),thermo-sensitive platelet-rich plasma gel (group C,n=5),orblank matrix gel (group D,n= 5).Corneal inflammationand ulceration were respectivelyevaluated by Ando’sand Trousdale’scriteria before and after treatment for 3,5,7,10 and 14 days.Pathological changes in cornea were observed by HEstaining.Results There were no significant differences in inflamma-tion and ulcer scores between group A and group D after treatment for 14 days (P >0.05).Com-pared with groups A and D,inflammation and ulcer scores decreased in groups B

  18. O cálculo do poder das lentes intra-oculares e o Orbscan-II. Parte 1: O poder óptico da córnea normal Power calculation of intraocular lenses and the Orbscan-II. Part 1: The power of the normal cornea

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    Érika C. Canarim de Oliveira

    2003-10-01

    Full Text Available OBJETIVO: Avaliar o poder dióptrico da porção central da córnea normal. MÉTODOS: Análise retrospectiva da topografia por varredura de fenda de luz e disco de Plácido em 30 olhos normais. RESULTADOS: Os poderes médios ceratométrico, anterior, da espessura e total; ópticos ceratométrico e total; axiais ceratométrico e total; tangencial total, equivalente e a soma do poder médio de ambas superfícies foram semelhantes (p>0,8361 nas quatro áreas centrais analisadas (0,04, 1, 3 e 5 mm de diâmetro. O poder médio posterior diminuiu de -6,62 D até -6,35 D (p=0,0030. A espessura média aumentou de 524 µm até 554 µm (p=0,0231, representando 0,13 D do poder total da córnea. Os poderes óptico (p0,4907 e à soma do poder de ambas superfícies (p>0,3868. O poder médio anterior foi ao redor de 7,5 vezes maior que o poder médio posterior. CONCLUSÕES: O poder real da córnea calculado usando ambas superfícies, sua espessura e os índices de refração fisiológicos é menor que o poder convencionalmente aceito e determinado pela medição da curvatura da superfície anterior e o índice de refração ceratométrico da córnea (FPURPOSE: To evaluate the dioptric power of the normal central cornea. METHODS: Retrospective analysis of combined slit-scanning and Placido-ring topography in 30 normal eyes. RESULTS: Keratometric-mean, anterior-mean, thickness-mean, and total-mean powers; keratometric-optical and total-optical, keratometric-axial and total-axial, and total-tangential powers; equivalent power and the addition of anterior and posterior mean powers, were similar (p>0.8361 in the four analyzed central areas with 0.04, 1.0, 3.0, and 5.0 mm diameter. The posterior-mean power decreased (p=0.0030 from -6.62 D to -6.35 D. The average thickness increased (p=0.0231 from 524 µm to 554 µm, representing 0.13 D of total-mean corneal power. Keratometric-optical (p0.4907, and to the addition of anterior-mean and posterior-mean powers (p>0

  19. OCULAR MICROBIAL POPULATION AS A 2-1 BETAMETHASONE DISSODIC FOSPHATE AND DISSODIC FOSPHATE/ACETATE DEXAMETHASONE MONITOR IN SWINE CORNEA TRANSPLANTED DOGS ESTUDO DA MICROBIOTA OCULAR COMO MONITOR DO 2-1 FOSFATO DISSÓDICO DE BETAMETASONA E DO FOSFATO DISSÓDICO/ACETATO DE DEXAMETASONA, EM CÃES QUE RECEBERAM TRANSPLANTES COM CÓRNEAS DE SUÍNOS

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    Nilo Sérgio Troncoso Chaves

    2007-09-01

    Full Text Available

    Ten mixed breed dogs, with a 10 kg average weight, were selected at Centro de Zoonoses de Goiânia. After being examined and considered healthy, the dogs were enumerated from 11 to 20 on their collars. Each animal had swine cornea implanted into the left eye. The swine cornea was obtained at Casa de Banha Caçula, a slaughterhouse, and conserved in a humid chamber during a maximum 6 hour period. Before surgery, each animal received 4 mg dissodic fosphate/acetate of dexamethasone IM and one drop of betamethasone dissodic fosphate and gentamycin sulphate. This medication was kept until euthanasia. Each dog had a superior fornix sample collected, the sample was immersed in 0.1% peptonized water, so that tests for aerobic bacteria and fungus could be realized. Each test was repeated with samples collected on days 7, 14, 21 and 28, after graft, and compared with those from day 0. The 12.8% Staphylococcus epidermidis on initial samples was caused by contamination during collection because it wasn’t found on the 28th day samples. This fact suggests that, although corticosteroids had caused systemic imunocellular supression, they didn’t make easier the bacterial development into the grafted eye.

    KEY-WORDS: Microbial population; corticosteroids; xenotranplants; cornea; canine; swine.

    Foram utilizados dez cães, sem raça definida, com peso médio de 10kg, selecionados no Centro de Zoonoses da Prefeitura de Goiânia. Após examinados e considerados sadios, foram numerados de 11 a 20 na respectiva coleira. Cada cão, a seu tempo, teve implantada no olho esquerdo córnea de suíno, este abatido no frigorífico Casa de Banha Caçula. A córnea foi conservada em câmara úmida pelo

  20. An experimental study on the fate of the amniotic membrane after amniotic membrane transplantation for acute alkaline burn of rat cornea%羊膜移植治疗大鼠角膜碱烧伤后羊膜转归的研究

    Institute of Scientific and Technical Information of China (English)

    陈酉; 晏晓明; 吴海荣; 荣蓓

    2012-01-01

    及角膜基质间,且同一种羊膜移植方法中羊膜与角膜融合的位置关系可以是以上3种位置关系中的一种或多种同时存在,但差异无统计学意义(H=4.206,P=0.122).结论 羊膜溶解后可存在于角膜组织中,无缝线羊膜移植较传统羊膜移植方法手术时间短、炎症反应轻,在角膜视路病变治疗中具有更广阔的应用前景.%Objective Use three different methods of amniotic membrane transplantation for acute alkaline burn of rat cornea,to investigate the difference on operation time,reabsorption time of amniotic membrane,integration patterns of amniotic membrane into the cornea among the three amniotic membrane transplantation methods.Methods SD rats were randomly assigned into five groups.Group A: simply alkaline burn of cornea; Group B: inlay method; Group C: overlay method; Group D: sutureless method;Group E: normal.Prepared the model of corneal alkaline burn of the right eyes of group A-D rats,performed three different methods of amniotic membrane transplantation on Group B-D rats respectively within 24 hours after alkaline burn.The operation time was recorded.Observed the eyes with slit-lamp microscopy after transplantation,recorded the reabsorption time of amniotic membrane.HE staining and immmunohistochemical staining against human collagen Ⅳ were performed for pathological study.The results were analysed with Image-Pro Plus 6.0 software.The integration patterns of amniotic membrane into the cornea after amniotic membrane reabsorbed were observed.Results ( 1 ) Operation time: Group B was ( 35.500 ± 2.878 )minutes ; Group C was ( 33.375 ± 2.973 ) minutes ; Group D was (9.875 ± 1.246 ) minutes.There was statistical significance between group B and group D ( P < 0.001 ),group C and group D ( P < 0.001 ).There was no statistical significance between group B and group C (P =0.102).(2) Reabsorption time of amniotic membrane: Group B was (16.625 ±3.662) days; Group C was (9.250 ±2.188) days

  1. EntransterTM纳米载体介导大鼠角膜CD25siRNA转染的效果及安全性评估%The efficiency and safety assessment of EntransterTM nanoparticle carrier for CD25 siRNA transfection in rat cornea

    Institute of Scientific and Technical Information of China (English)

    秦琴; 石韵洁; 赵敏

    2016-01-01

    细胞凋亡数明显多于EntransterTM-CD25 siRNA组、单纯CD25 siRNA组和生理盐水组,差异均有统计学意义(均P=0.00).免疫荧光检测显示,CD11b荧光主要分布于角膜上皮层和角膜基质层,随着基因转染后时间的延长,脂质体-CD25 siRNA组大鼠角膜组织中CD11b的表达量逐渐增加,基因转染后24 h时荧光强度达峰,随后逐渐减弱,至转染后第7天仍可见弱荧光.EntransterTM-CD25 siRNA组、单纯CD25siRNA组和生理盐水组大鼠角膜组织中均未发现CD11b的荧光表达. 结论 EntransterTM纳米材料作为载体转染CD25 siRNA于正常SD大鼠角膜具有转染效率高、毒性低、不引起角膜免疫反应的特点,可作为角膜疾病基因治疗的合适载体.%Background Gene transfection is an effective therapeutic avenue to target many kinds of eye diseases.Non-viral vectors with high transfection efficiency,long-term expression,low toxicity and high expression levels are pivotal in gene therapy of corneal disease.Objective This study was to evaluate and compare the safety and efficiency between EntransterTM and liposome vectors for transfer of CD25 siRNA in rat cornea.Methods Eighty male SPF SD rats were randomly divided into EntransterTM-CD25 siRNA group,liposome-CD25 siRNA group,simple CD25 siRNA group and normal saline solution (NSS) group with the right eye as experimental eyes.Corneal epithelia of the rats were completely removed after ocular surficial anesthesia,and 50 μl EntransterTM-CD25 siRNA,liposome-CD25 siRNA,CD25 siRNA solution and NSS were topical administered in the eyes respectively.Ocular response and green fluorescence number on the corneas were examined under the slit lamp assisted microscope 12 hours,24 hours,3 days and 7 days after use of the drugs.The rats were sacrificed and the corneas were obtained,and corneal histopathological examination was performed by using hematoxylin eosin stain.The gene transferred efficiency in the corneas was evaluated by

  2. Análise da qualidade das córneas doadas e do intervalo entre óbito, enucleação e preservação após a implantação de novas normas técnicas e sanitárias em Banco de Olhos Universitário Comparative analysis of the donor cornea quality and of the interval between death and preservation before and after new sanitary and technique rules in a University Eye Bank

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    Fabio Zantut

    2012-12-01

    Full Text Available OBJETIVO: Comparar o intervalo entre o óbito e a enucleação (ΔT-O-E, entre a enucleação e a preservação (ΔT-E-P e a qualidade da córnea antes e após a implantação de novas normas técnicas e sanitárias baseadas na Resolução RDC 347. MÉTODOS: Estudo retrospectivo em que foram avaliados os prontuários dos doadores de córnea do Banco de Tecidos Oculares da Santa Casa de São Paulo, 2 anos antes e 2 anos depois da implementação de novas normas sanitárias. RESULTADOS: Foi observado aumento do número absoluto de 205 para 374 doadores após as mudanças adotadas. Não foi observada diferença estatisticamente significante no Δt-O-E e ΔT-E-P antes e após as mudanças implantadas. Do total de 1.105 córneas doadas, foi observado 388 córneas doadas antes das mudanças e 717 córneas doadas após as mudanças implementadas. Foi observado aumento estatisticamente significante da graduação da qualidade da córnea doada de 1,76 ± 0,90 para 1,94 ± 0,88 após a implementação das novas normas da Resolução. CONCLUSÃO: Após as mudanças técnicas e sanitárias exigidas pela Resolução 347, houve grande aumento no número de córneas doadas, captadas e preservadas. O Banco de Tecidos Oculares não diminuiu os ΔT O-E e ΔT E-P. A qualidade da córnea apresentou-se inferior após as mudanças realizadas no setor.PURPOSE: To compare the interval between death and enucleation (ΔT-O-E, between enucleation and preservation (ΔT-E-P and the quality of the cornea before and after the implantation of new technique and sanitary rules. METHODS: A retrospective study that evaluated the records of cornea donors in Sao Paulo's Santa Casa Eye Tissue Bank 2 years before and 2 years after the implementation new sanitary rules. RESULTS: An increase was observed in the absolute number of 205 to 374 donors following the adopted changes. There was no statistically significant difference in Δt-O-E and ΔT-E-P before and after the implemented

  3. Influence of Tobradex on Three Cytokines in Tears and the Restoration of Cornea after LASIK%典必殊对 LASIK 术后角膜修复及泪液中3种细胞因子的影响

    Institute of Scientific and Technical Information of China (English)

    张玉生; 冯有为

    2014-01-01

    -ceiving Laser in situ keratomileusis ( LASIK) , to observe the rules of their change after receiving additional Tobradex treat-ment and analyze the relations between cytokines and daily dosage and treatment course .Also, to discuss the influence of this treatment on the healing of cornea , eyesight and eye pressure for guiding reasonable postoperative drug administration . Method All 96 patients with myopia ( 189 eyes ) who received LASIK treatment , were randomly divided into three test groups of different postoperative Tobradex treatment course .All groups began to receive Tobradex treatment 24h after surger-y, the first group was treated for one week the second two weeks and the third four weeks .The tear samples of each group were collected before and 24h after surgery, one week, two weeks and four weeks after treatment to determine the concentra-tion of 3 cytokines IL-1a, IL-2 and TNF-αand analyze the influence of different daily dosage and treatment course on the ef -ficacy, healing of cornea , eyesight and eye pressure .All data were processed statistically with SAS 6.12 statistic software package.Results The content of IL-1a, IL-2 and TNF-αin tears of patients in three groups 24 hours after surgery in-creased substantially and had significant difference ( P0.05).In examination for 3 groups 24h after surgery, the wounds of cornea had all been covered by epi-thelial cells , the restoration of corneal flap was good and the wounds healed one week after surgery .Two weeks and four weeks after surgery, their eyesight improved and restored , without obvious difference ( P>0.05 ) .The occurrence rate of corticosteroid induced ocular hypertension was different in three groups two weeks after surgery , which was of statistical sig-nificance ( P<0.05 ) .Four weeks after surgery , ocular hypertension disappeared in test groups one and two , however the occurrence rate of corticosteroid induced ocular hypertension in test group three was still as high as 13.16%, the difference

  4. Changes in high order aberrations of anterior and posterior surfaces of cornea before and after phacoemulsification%超声乳化白内障吸除术后角膜前后表面高阶像差的变化

    Institute of Scientific and Technical Information of China (English)

    王娟; 汤欣; 张帅; 李丽华

    2008-01-01

    目的 探讨利用Pentacam观察超声乳化白内障吸除术前后角膜前后表面高阶像差的变化.方法 前瞻性系列病例研究.对45例(51只眼)年龄相关性白内障患者行3.2 mm透明角膜切口的超声乳化白内障吸除联合折叠型人工晶状体植入术,分别于术前1 d,术后7 d、1个月及3个月利用Pentacam测量角膜前后表面的高阶像差(包括总的高阶像差、球差、彗差、三叶草以及3~6阶像差),将角膜前、后表面高阶像差按直径范围不同(3 mm直径和6 mm直径)分为两组,用具有一个重复测量的两因素设计定量资料方差分析方法对两组数据分别进行统计学分析.结果 角膜前表面总的高阶像差术前1 d为(0.289±0.171)μm,至术后3个月时轻度增加为(0.312±0.158)μm(3 mm直径);术前1 d为(0.980 ±0.215)μm,至术后3个月时轻度增加为(1.054±0.308)μm(6mm直径),但手术前后变化无统计学差异(F=1.55,P=0.22),且两组总的高阶像差随时间的变化趋势相同(F=0.95,P=0.42);其余各项高阶像差手术前后的变化与总的高阶像差的变化相似.角膜后表面总的高阶像差术前1 d为(0.548±0.220)μm,至术后3个月时明显增加为(0.661±0.275)μm(3 mm直径);术前1 d为(1.780±0.453)μm,至术后3个月时明显增加为(1.945±0.532)μm(6mm直径),手术前后变化差异有统计学意义(F=15.83,P=0.00),且两组总的高阶像差随时间的变化趋势不同(F=12.46,P=0.00);其余各项高阶像差手术前后的变化与总的高阶像差的变化相似.结论 超声乳化白内障吸除术后角膜前表面高阶像差的变化不影响术后患者的视觉质量.但是,手术前后角膜后表面高阶像差发生了显著的变化,可能影响术后患者的视觉质量.%Objective To study the effects of phacoemulsification surgery on the optical high order aberrations(HOA)of the cornea measured with Pentacarm.Methods It was a prospective case series study.HOAs of the anterior and

  5. Bee sting of the cornea: A running case report

    Directory of Open Access Journals (Sweden)

    Roland Höllhumer

    2015-03-01

    Full Text Available Bee stings that present with ocular sequelae are infrequently reported in the literature. The present report is of a retained corneal bee stinger with a delayed presentation. A review of case reports reveals a number of potential ocular complications of bee stings. The ocular sequelae and treatment options are reviewed.

  6. Spheroid degeneration of conjunctiva and cornea. Two years' follow up.

    Science.gov (United States)

    Norn, M

    1980-10-01

    Twenty-six subjects with spheroid degeneration were followed up after two years. The number of colourless conjunctival droplets was seen to have increased by on an average 46% (2 alpha = 0.05) and that of autofluorescent conjunctival droplets by 223% (2 alpha less than 0.01). Counting within the individual sites sites disclosed that some droplets will disappear (not less than 30 and 21% respectivelY), while recently formed will constitute at least 76 and 243%. The number of areas with band-shaped keratopathy was found to rise from 3 to 26 (P less than 0.001) out of 104 possibilities, (nasally and temporally of right and left eye). Vital staining (fluorescein, rose bengal, tetrazolium, alcian blue) showed the epithelium above the droplets to be intact, and the droplet-containing eyes were found not to be abnormally dry (break up time, tear production).

  7. A Novel Insight into Keratoconus: Mechanical Fatigue of the Cornea

    OpenAIRE

    Norouzpour, Amir; Mehdizadeh, Alireza

    2012-01-01

    An integrated model for keratectasia risk assessment has received much attention over many years. The objective of this article is to propose a more complete, conceptual model by which high risk individuals can be screened, even with no topographic irregularity or corneal thinning. In this model, corneal ectasia results from the fatigue effect of cyclic shear stress and tensile stress, caused by eye rubbing and fluctuating intraocular pressure (IOP), respectively, on corneal microstructures. ...

  8. Intergrin-dependent neutrophil migration in the injured mouse cornea

    Science.gov (United States)

    As an early responder to an inflammatory stimulus, neutrophils must exit the vasculature and migrate through the extravascular tissue to the site of insult, which is often remote from the point of extravasation. Following a central epithelial corneal abrasion, neutrophils recruited from the peripher...

  9. Diverse set of Turing nanopatterns coat corneae across insect lineages.

    Science.gov (United States)

    Blagodatski, Artem; Sergeev, Anton; Kryuchkov, Mikhail; Lopatina, Yuliya; Katanaev, Vladimir L

    2015-08-25

    Nipple-like nanostructures covering the corneal surfaces of moths, butterflies, and Drosophila have been studied by electron and atomic force microscopy, and their antireflective properties have been described. In contrast, corneal nanostructures of the majority of other insect orders have either been unexamined or examined by methods that did not allow precise morphological characterization. Here we provide a comprehensive analysis of corneal surfaces in 23 insect orders, revealing a rich diversity of insect corneal nanocoatings. These nanocoatings are categorized into four major morphological patterns and various transitions between them, many, to our knowledge, never described before. Remarkably, this unexpectedly diverse range of the corneal nanostructures replicates the complete set of Turing patterns, thus likely being a result of processes similar to those modeled by Alan Turing in his famous reaction-diffusion system. These findings reveal a beautiful diversity of insect corneal nanostructures and shed light on their molecular origin and evolutionary diversification. They may also be the first-ever biological example of Turing nanopatterns.

  10. Apparatus for preparing cornea material for tabbed (sutureless) transplantation

    Science.gov (United States)

    Collins, J.P.

    1997-07-22

    A tool and a method for preparing a donor material used in sutureless corneal transplants uses a first cutting portion to prepare a donor blank having tabbed portions extending outwardly radially. A second cutting portion is used to cut the central portion of the blank. The tool is used as a guide member for the second cutting portion. In one embodiment the tool has slits laterally defined therethrough which allow the tabbed portions of the donor material to be thinned to a desired thickness using a scalpel. In an another embodiment the second cutting portion is a round trephine which is used to simultaneously trim each of the tabbed portions. 26 figs.

  11. Supercritical Carbon Dioxide-Assisted Decellularization of Aorta and Cornea.

    Science.gov (United States)

    Guler, Selcan; Aslan, Bahar; Hosseinian, Pezhman; Aydin, Halil Murat

    2017-09-01

    Tissue engineering approaches utilize both natural and synthetic materials in the repair and regeneration processes. A naturally sourced material for this purpose is required to be free from any antigenic matter such as cells or cellular components. Decellularization of tissues may be achieved through chemical or physical removal agents. Supercritical carbon dioxide (sc-CO2) has been used on the purpose of removing bioburden from tissues and offers an alternative to the traditionally used treatment methods. In addition to many advantages it offers with regard to the successful decellularization of tissues, it is known to have a sterilization effect. This study provides an insight into sc-CO2-assisted decellularization trials of corneal and aortic tissues. Results showed that high pressure of the fluid bursts the cells during the treatment and rapid depressurization was found to be effective in the removal of the cells from the tissues. sc-CO2 decellularization offers significantly reduced treatment times, complete decellularization, and preserved extracellular matrix structure.

  12. Photorefractive keratectomy results in myopic patients with thin cornea eyes

    Directory of Open Access Journals (Sweden)

    Hassan Hashemi

    2015-01-01

    Conclusion: PRK is a safe, effective, and predictable procedure with desirable effects on mesopic CS in patients with corneal thickness <500 μm, which increases HOAs and decreases corneal integrity proportionate to its value before the procedure.

  13. Effects of radiofrequency hyperthermia on the healthy canine cornea

    Energy Technology Data Exchange (ETDEWEB)

    Glaze, M.B.; Turk, M.A.

    1986-04-01

    Radiofrequency hyperthermia was used to induce axial corneal lesions in the eyes of 10 dogs. Clinical observations were continued for up to 6 months, using biomicroscopy and indirect ophthalmoscopy. Eyes were harvested at intervals for light and electron microscopic evaluation. Clinical alterations included immediate corneal opacification and epithelial disruption at the site of electrode contact. Ulcerative keratitis persisted for 4 to 6 days, accompanied by anterior uveitis. Additional corneal changes included stromal thinning, edema, and vascularization. Final evaluation revealed negligible alterations in corneal contour or clarity 6 months after treatment. Microscopically, epithelial and superficial stromal necrosis preceded epithelial loss. Stromal alterations included edema (associated with focal endothelial detachments), vascularization, and inflammatory cell infiltration. Recovery was characterized by keratocytic hyperplasia and hypertrophy, epithelial proliferation, and stromal condensation.

  14. Pathogenesis of herpes simplex virus infections of the cornea

    NARCIS (Netherlands)

    J. Maertzdorf (Jeroen)

    2002-01-01

    textabstractThe identification of human herpes virus (HHV) infections can be traced back to ancient Greece where Herpes simplex vims (HSV) infections in humans were first documented. Hippocrates used the word "herpes", meaning to creep or crawl, to describe spreading skin lesions. Although the

  15. Advanced Squamous Cell Carcinoma of Cornea in a Child with ...

    African Journals Online (AJOL)

    causes marked alterations in the skin leading to keratosis, telangiectasia ... Keywords: Squamous cell carcinoma, surgical excision, Xeroderma Pigmentosum. How to cite this .... Typically, the first stage makes its appearance after the age of 6 ...

  16. A fibrin-related line of research and theoretical possibilities for the use of fibrin glue as a temporary basal membrane in non-perforated corneal ulcers and in photorefractive keratectomy (PRK-operated corneas Linha de pesquisa em fibrina e possibilidades teóricas de seu uso como membrana basal provisória em úlceras corneanas não perfuradas e em córneas operadas de ceratectomia fotorrefrativa (PRK

    Directory of Open Access Journals (Sweden)

    José Américo Bonatti

    2007-10-01

    Full Text Available PURPOSE: To report a specific line of research developed at the University of São Paulo/Brazil on fibrin glue used for sealing corneal perforations and the perspectives of use on non-perforated corneal ulcers and photorefractive keratectomy-operated corneas. METHODS: To describe fibrin glue manufacture, development of a device to test the glued perforated corneal area resistance, subsequent experimental investigations of the use of the fibrin glue in corneal perforations, reporting its efficacy, mechanical resistance experiments and histological study. Finally, the medical literature basis is searched to propose studies on the use of fibrin as a temporary basal membrane on non-perforated corneal surfaces like non-infectious corneal ulcers and on post-photorefractive keratectomy corneal surfaces. RESULTS: The development of fibrin glue, the device for resistance experiments, the efficacy, resistance and histological studies on fibrin glue used for sealing corneal perforations are reported as well as the scientific literature basis for the proposed studies on the use of fibrin as a temporary basal membrane on non-perforated corneas like non-perforated corneal ulcers and photorefractive keratectomy corneal surfaces. CONCLUSION: A specific line of research was reported on fibrin glue to seal corneal perforations at the University of São Paulo/Brazil and the theoretical perspectives for the use of fibrin in non-perforated corneal ulcers and on photorefractive keratectomy-operated corneas in an attempt to reduce corneal haze.OBJETIVO: Relatar uma linha de pesquisa desenvolvida no Brasil (Universidade de São Paulo em cola de fibrina para tamponamento de perfuração corneana e a perspectiva de seu uso em úlceras corneanas não perfuradas e em córneas operadas de ceratectomia fotorrefrativa. MÉTODOS: Relatar a fabricação da cola de fibrina, desenvolvimento de instrumentação para ensaio de resistência da área colada, estudo experimental da

  17. Clinical effect of bioengineered cornea and in vivo confocal microscopy observation after human lamellar keraplasty%生物角膜用于人角膜板层移植术后的临床疗效及激光扫描共焦显微镜动态观察

    Institute of Scientific and Technical Information of China (English)

    王素娟; 张月琴; 李金; 余晓菲; 窦新岩; 王丽娅

    2016-01-01

    Background Xenotransplantation is arousing more attention of researchers because of the lack of corneal donors.Biological corneal scaffolds constructed by porcine corneal acellular stroma appears to have an acceptable biocompatibility.However,its clinical effects and the histomorphological features in the corneal tissue of receipts' are still unclear.Objective This study was to evaluate the viability of bioengineered corneas as a new material of human lamellar keratoplasty and observe the in viva biological features after human keratoplasty under the laser confocal microscope.Methods A prospective serial cases observational study was carried out.Fifteen eyes of 15 patients with infectious keratitis were enrolled in Henan Eye Hospital from February to August 2014 under the approval of Ethic Committee of Henan Eye Hospital and informed consent of each patient, including 4 eyes of fungal keratitis,1 eye of bacterial keratitis, 9 eyes of mixed infectious keratitis and 1 eye of leucoma.Corneal lamellar transplantation was performed on the eyes with the bioengineered corneas as grafts and the follow-up time was one year.The survival of grafts was assessed and scored, and the indices including corneal transparency,neovascularization, graft lysis or inflammatory recurrence and visual acuity (logMAR) were evaluated.The morphology and density of corneal epithelial cells and endothelial cells, corneal stroma and subepithelial neural fibers were examined by laser confocal microscope 3,6,9 and 12 months after surgery.Results Postoperative inflammatory response was seen 3 days and disappeared 7 days after surgery.The grafts were clear 1 month after surgery, and no corneal dissolution was found during the follow-up duration.Glaucoma occurred in 1 eye at 6 months and graft rejection occurred in another eye 12 months after surgery.The logMAR, corneal transparency scores and corneal neovascularization scores improved after surgery in comparison with before surgery,with a significant

  18. 去除上皮瓣的微型角膜刀法准分子激光角膜上皮瓣下磨镶术后早期兔角膜的修复方式研究%The early post-operative wound healing mode study of the rabbit cornea after flap-free epipolis laser in-situ keratomileusis

    Institute of Scientific and Technical Information of China (English)

    刘玺; 杜之渝; 向一旻; 黄正

    2009-01-01

    Objective To evaluate the wound healing mode of rabbit corneal epithelium after Epi-LASIK(epipolis laser in-situ keratomilensis ) and Flap-free Epi-LASIK (Flap-free epipolis laser in-situ keratomileusia).Methods Twenty-four New Zealand white rabbits(48 eyes) were randomly divided into four groups.There were six rabbits in every group, which were randomly treated with Epi-LASIK in one eye and Flap-free Epi-LASIK in the other by VISX20/20 excimer laser.Other three rabbits(6 eyes) without any treatment were used as control.The corneal epithelium wound healing mode was observed at 1,2,4,7 days after surgery by light microscope and electron microscope.The number of keratocytes cells in the central anterior stroma were counted by hematoxylin-cesin-stained.The expression of basic fibroblast growth factor (bFGF) in corneal stroma were assessed by Immunohistochemistry staining.Cornea stromal cell apoptosis was evaluated by terminal deoxyribonuc1eotidyl transferase-mediated deoxynuridine triphosphate nick end labeling (TUNEL) assay.All the data was analysised by t-test to evaluate the different of wound healing mode after Epi-LASIK and Flap-free Epi-LASIK.Results The findings of light microscope and electron microscope investigation demonstrated that, at the first day after surgery, there was one layer of neogenesis of the corneal epithelial cells covering the area of surgery in Flap-free Epi-LASIK specimens.It would increase gradually after 7 days.At the first day after the surgery, the base membrane of the corneal epithelium was tightly attached to the stroma in Epi-LASIK specimens.At the second day after the surgery, there was edema observed on the epithelium flap in the Epi-LASIK specimens.There were more keratocytes cells found at 4 days after surgery in Flap-free Epi-LASIK group (33.85±3.39) than that in Epi-LASIK group (t=-2.315,P<0.05).The expression of bFGF in Flap-free Epi-LASIK group at 2,4 days after surgery were 101.75±8.07 and 110.56±9.00, which were more

  19. Effects of topical 2% cyclosporine A on the corneas of dogs subjected to lamellar keratoplasty with a graft of equine pericardium preserved in glycerin: clinical and morphological evaluation Efeitos da aplicação tópica da ciclosporina A a 2% sobre a córnea de cães submetidos à ceratoplastia lamelar com implante de pericárdio de eqüino preservado em glicerina: avaliação clínica e morfológica

    Directory of Open Access Journals (Sweden)

    Roseli Borges Teixeira

    2004-02-01

    Full Text Available The effects of topical 2% cyclosporine A on the cornea of dogs subjected to experimental lamellar keratoplasty with an equine pericardial graft were evaluated. Ten dogs were grouped to be evaluated 3, 7, 15, 30 and 60 days after surgery. Animals received bilateral grafts followed by the application of a 2% cyclosporine A ointment on the left eye (treated eye and the ointment base on the right eye (control eye twice a day. The ophthalmic evaluation showed profound bilateral blepharospasm, photophobia and a mucous secretion until the 7th day after surgery; corneal vascularization starting in the limbus was observed as early as the 3rd day in both eyes; opacification and vascularization were more intense in the treated cornea on days 15 and 30 after surgery. Vascularization was still evident on the 60th day, and looked similar in treated eyes and control eyes. The histologic evaluation showed a complete bilateral reepithelization and corneal vascularization three days after the surgery; intense vascularization in both eyes on days 15 and 30, that was much more pronounced in the treated cornea; and a bilateral predominance of polymorphonuclear cells until day 15, and mononuclear cells on day 30. Intact epithelium and stroma with new vessels, as well as graft absorption, in both eyes, were seen on the 60th day. The lamellar keratoplasty with equine pericardial graft was an effective model to study the inflammatory kinetics and corneal vascularization phenomenon. In this study, cyclosporine A did not inhibit corneal vascularization and it did not interfere in the corneal cicatricial process.Foram avaliados os efeitos da ciclosporina A a 2% sobre a córnea de cães submetidos à ceratoplastia lamelar experimental com implante de pericárdio de equino. Dez cães foram divididos em grupos para estudo aos três, sete, 15, 30 e 60 dias de pós-operatório, recebendo implantes bilaterais e em seguida aplicação da pomada com ciclosporina A a 2% no olho

  20. CoQ10-containing eye drops prevent UVB-induced cornea cell damage and increase cornea wound healing by preserving mitochondrial function.

    Science.gov (United States)

    Mencucci, Rita; Favuzza, Eleonora; Boccalini, Carlotta; Lapucci, Andrea; Felici, Roberta; Resta, Francesco; Chiarugi, Alberto; Cavone, Leonardo

    2014-10-09

    We evaluated the potential protective effects of Coenzyme Q10 (CoQ10) on human corneal cells and rabbit eyes after ultraviolet B (UVB) exposure and a model of wound healing in rabbit eyes after corneal epithelium removal. Human corneal epithelium cells (HCE) were exposed to a source of UVB radiation (312 nM) in the presence of different CoQ10 concentrations or vehicle. The mitochondrial function and cell survival were evaluated by means of 3-(4,5-dimethylthiazole-2-yl)2,5-diphenyl-tetrazolium (MTT) reduction and lactic dehydrogenase (LDH) release. Furthermore, quantitation of oxygen consumption and mitochondrial membrane potential were conducted. In vivo rabbit models were adopted to evaluate the effect of CoQ10 on UVB-induced conjunctival vessel hyperemia and corneal recovery after ethanol induced corneal lesion. In UVB-exposed HCE cells, CoQ10 addition led to an increased survival rate and mitochondrial function. Furthermore, oxygen consumption was maintained at control levels and adenosine triphosphate (ATP) decline was completely prevented in the CoQ10-treated cells. Interestingly, in an in vivo model, CoQ10 was able dose-dependently to reduce UVB-induced vessel hyperemia. Finally, in a model of corneal epithelium removal, 12 hours from surgery, animals treated with CoQ10 showed a reduction of damaged area in respect to vehicle controls, which lasted until 48 hours. We demonstrated that CoQ10 reduces corneal damages after UVB exposure in vivo and in vitro by preserving mitochondrial function. Also, for the first time to our knowledge we showed that the administration of CoQ10 after corneal epithelium removal promotes corneal wound healing. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

  1. The Effect of Fibronectin on Re-epithelialization of Rabbits Cornea after Alkali Burn

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    The authors found experimentally that (1) fibronectin enhanced the healing of rabbit corneal epithelium after alkali burn and prevented the secondary breakdown; (2) it rapidly deposited on the denuded basement membrane to disappear as epithelial cells slided over, and (3) ultrastructurally, the neighbouring epithelial cells became flattened, with filopodia at the advancing edge, and extended to the wounded areas at 24 hours after the burn. However, the epithelial defects recurred 72 hours after the burn...

  2. Treatment of the Cornea Using Transcytotic Delivery into the Tear Film

    Science.gov (United States)

    2015-12-01

    hourly, challengingpa- tient compliance [5]. In many cases, ocular diseases such as scleritis [6] and fungal [7], bacterial and viral keratitis [8...treatment of bacterial keratitis, Am J. Ophthalmol. 106 (1988) 279–281. [13] M.C. Edman, R.R. Marchelletta, S.F. Hamm-Alvarez, Lacrimal gland...such as the corneal, limbal and con- junctival epithelial cells, meibomian and LG epithelium, retina, and ret- inal pigmented epithelium/choroid [48

  3. Use of Cross-linked Donor Corneas as Carriers for the Boston Keratoprosthesis

    Science.gov (United States)

    2016-10-03

    Chemical Injuries; Unspecified Complication of Corneal Transplant; Autoimmune Diseases; Ocular Cicatricial Pemphigoid; Stevens Johnson Syndrome; Lupus Erythematosus, Systemic; Rheumatoid Arthritis; Other Autoimmune Diseases

  4. Research progress on applications of hDPSCs in cornea reconstruction

    Directory of Open Access Journals (Sweden)

    Jun Li

    2017-09-01

    Full Text Available The corneal reconstruction is tosurgial recover the structure integrity and corneal function after suffered from various trauma, inflammation and degenerative diseases. The corneal diseases caused millions of people worldwide suffering from eyesight damages and even blindness. At present, the corneal transplant is the main therapy for corneal blindness. However, the shortage in donor corneal issue is a worldwide problem and the failure due to the immunologic rejection of host is common. Nowadays, with the development of tissue culture and bioengineering technology, the application prospect of autologous stem cell transplantation is becoming more and more popular which might replace the allogeneic transplantation, becoming an important clinical treatment of regenerative medicine. Human dental pulp stem cells(hDPSCsis a class of adult stem cell divided from the third molar teeth. Both hDPSCs and corneal cell are from the cranial nerve in embryonic ectoderm. Extensive researches show that the hDPSCs have the potentialities in corneal cell differentiation without causing immunologic rejection of the recipient. These findings manifested the potentials of hDPSCs in the clinical applications related to ocular surface reconstruction. In this paper, the features and current investigation status of hDPSCs in ocular surface reconstruction are reviewed.

  5. Value of human amniotic epithelial cells in tissue engineering for cornea.

    Science.gov (United States)

    Fatimah, Simat Siti; Ng, Sook Luan; Chua, Kien Hui; Hayati, Abdul Rahman; Tan, Ay Eeng; Tan, Geok Chin

    2010-11-01

    Human amniotic epithelial cells (hAECs) are potentially one of the key players in tissue engineering due to their easy availability. The aim of the present study was to develop an optimal isolation and transportation technique, as well as to determine the immunophenotype and epithelial gene expression of hAECs. Amnion was mechanically peeled off from the chorion and digested with trypsin-ethylenediaminetetraacetic acid. The isolated hAECs were cultured in medium containing 10 ng/mL epidermal growth factor until P4. The epithelial gene expression, cell surface antigen and protein expression of hAECs were analyzed by quantitative polymerase chain reaction, flow cytometry and immunocytochemistry. hAECs were also cultured in adipogenic, osteogenic and neurogenic induction media. The best cell yield of hAECs was seen in the digestion of 15 pieces of amnion (2 × 2 cm) and isolated 30 min after digestion with trypsin. F12:Dulbecco's modified eagle medium was the best medium for short term storage at 4 °C. hAECs expressed CD9, CD44, CD73 and CD90, and negligibly expressed CD31, CD34, CD45 and CD117. After serial passage, CK3, CK19 and involucrin gene expressions were upregulated, while p63, CK1 and CK14 gene expressions were downregulated. Sustained gene expressions of integrin β1 and CK18 were observed. At initial culture, these cells might have stem-like properties. However, they differentiated after serial passage. Nonetheless, hAECs have epithelial stem cell characteristics and have the potential to differentiate into corneal epithelial cells. Further investigations are still needed to elucidate the mechanism of differentiation involved and to optimize the culture condition for long term in vitro culture.

  6. Short-term azithromycin treatment promotes cornea allograft survival in the rat.

    Directory of Open Access Journals (Sweden)

    Katrin Wacker

    Full Text Available BACKGROUND: Any inflammatory response following corneal transplantation may induce rejection and irreversible graft failure. The purpose of this study is to analyze the anti-inflammatory effect of azithromycin (AZM following experimental keratoplasty in rats. METHODS: Corneal transplants were performed between Fisher-donor and Lewis-recipient rats. Recipients were postoperatively treated three times daily with AZM, miglyol, ofloxacin or dexamethasone eye drops. As an additional control, AZM was applied following syngeneic keratoplasty. Furthermore, short-term treatments with AZM for seven days perioperatively or with AZM only three days prior to the transplantation were compared to appropriate controls. All transplants were monitored clinically for opacity, edema, and vascularization. Infiltrating CD45(+, CD4(+, CD8(+, CD25(+, CD161(+ and CD163(+ cells were quantified via immunohistochemistry. RESULTS: AZM significantly promoted corneal graft survival compared with miglyol or ofloxacin treatment. This effect was comparable to topical dexamethasone. No adverse AZM effect was observed. Histology confirmed a significant reduction of infiltrating leukocytes. The short-term application of AZM for three days prior to transplantation or for seven days perioperatively reduced corneal graft rejection significantly compared with the controls. CONCLUSIONS: Along with antibiotic properties, topical AZM has a strong anti-inflammatory effect. Following keratoplasty, this effect is comparable to topical dexamethasone without the risk of steroid-induced adverse effects. Short-term treatment with AZM three days prior to the transplantation was sufficient to promote graft survival in the rat keratoplasty model. We therefore suggest further assessing the anti-inflammatory function of topical AZM following keratoplasty in humans.

  7. Public Health Implications of the 1540 nm Laser on the Cornea

    Science.gov (United States)

    2007-05-30

    Cambridge [Eng.]: University Press. Fleischauer, Eric. 2005. Blinding Light As A Weapon: Lasers Pose Threat To Airplane Pilots Decatur Daily News, Jan 7...epithelium in vitro. Invest Ophthalmol Vis Sci 41: 3754-62; 2000. Esquenazi S, He J, Bazan NG, Bazan HE. Comparison of corneal wound-healing...Vis Sci 41, no. 12: 3754-62. Endangered Species Act Of 1973. 1973. Esquenazi, S., J. He, N. G. Bazan , and H. E. Bazan . 2005. Comparison Of Corneal

  8. The spatial organization of Descemet's membrane-associated type IV collagen in the avian cornea

    OpenAIRE

    1990-01-01

    The organization of type IV collagen in the unconventional basement membrane of the corneal endothelium (Descemet's membrane) was investigated in developing chicken embryos using anti-collagen mAbs. Both immunofluorescence histochemistry and immunoelectron microscopy were performed. In mature embryos (greater than 15 d of development), the type IV collagen of Descemet's membrane was present as an array of discrete aggregates of amorphous material at the interface between Descemet's membrane a...

  9. Long-term results of cornea collagen cross-linking with riboflavin for keratoconus

    Directory of Open Access Journals (Sweden)

    Vinay Agrawal

    2013-01-01

    Full Text Available Corneal collagen cross-linking with riboflavin and UVA light (CXL is the only method designed to arrest the progression of keratoconus. Visual improvement generally starts 3 months after treatment. Reduction is coma seen on aberrometry in early postoperative phase is also responsible for the improvement in visual acuity. In the light of currently available data we can thus say that CXL is a safe procedure that is successful in arresting keratoconus.

  10. Corneal topography with conical null-screen for non-symmetric aspheric corneas

    Science.gov (United States)

    Armengol-Cruz, Victor de Emanuel; Osorio-Infante, Arturo I.; Campos-García, Manuel; Cossio-Guerrero, Cesar; Díaz-Uribe, José Rufino

    2016-09-01

    In this work, we will present some improvements to the conical null-screen based corneal topographer, for testing aspheric surfaces without rotational symmetry. We present the formulae to design the conical null-screen in such a way that the image on the CCD is a perfect array of spots; departures from this geometry are due to deformation or misalignment of the surface. Additionally, we will explain how to improve the algorithms to find the normals of corneal surface. Finally, we will evaluate the topography of a spherical surface.

  11. Evaluation of Surface anesthetic action of Aqueous Extract of Piper Betel leaf On Rabbit Cornea

    Directory of Open Access Journals (Sweden)

    Dr.T.Jayasree

    2014-07-01

    Full Text Available Aim: Piper betel Linn. (Piperaceae commonly known as betel leaf and the habit of betel chewing is widely prevalent in most parts of India. It is claimed to have aphrodisiac, laxative, antimicrobial, mucolytic, antiinflammatory and euphoric properties and proven antimutagenic and anti-carcinogenic effect. It is commonly observed that chewing of betel leaf produces numbness in the mouth, suggesting a possible local anesthetic effect. This observation prompted us to take this study . The aim of the study was to evaluate the local anesthetic activity of betel leaf extract after autoclaving the extract of betel leaf. Materials and methods: Extract of plain betel leaf, was tested for surface anesthetic activity using rabbits. Aqueous extraction of Piper betel leaf (AEPBL done by Soxhelts apparatus .Twenty male Rabbit’s were taken and divided in to four groups each group contain 5 animals, Group I - Standard (2% xylocaine, Group II - Test 0.3% (AEPBL, Group III - Test 0.6 % (AEPBL,Group IV - Test 12 % (AEPBL was instilled in conjunctival sac of right eyes. Standard protocol was followed to elicit light reflex, corneal reflex and to measure pupillary size after instilling the test drugs in the eye. There was dose dependent increase in onset and duration of local anesthetic activity with 6% and 12% doses of alcoholic extract of Piper betel leaf. Results: Betel leaf showed significant surface anesthetic activity comparable to that of Xylocaine. Conclusion: As a surface anesthetic, the onset was as quick as xylocaine and the duration was shorter than xylocaine

  12. Development of high refractive ZnS/PVP/PDMAA hydrogel nanocomposites for artificial cornea implants.

    Science.gov (United States)

    Zhang, Quanyuan; Su, Kai; Chan-Park, Mary B; Wu, Hong; Wang, Dongan; Xu, Rong

    2014-03-01

    A series of high refractive index (RI) ZnS/PVP/PDMAA hydrogel nanocomposites containing ZnS nanoparticles (NPs) were successfully synthesized via a simple ultraviolet-light-initiated free radical co-polymerization method. The average diameter of the ZnS NPs is ∼ 3 nm and the NPs are well dispersed and stabilized in the PVP/PDMAA hydrogel matrix up to a high content of 60 wt.% in the hydrogel nanocomposites. The equilibrium water content of ZnS/PVP/PDMAA hydrogel nanocomposites varied from 82.0 to 66.8 wt.%, while the content of mercaptoethanol-capped ZnS NPs correspondingly varied from 30 to 60 wt.%. The resulting nanocomposites are clear and transparent and their RIs were measured to be as high as 1.58-1.70 and 1.38-1.46 in the dry and hydrated states, respectively, which can be tuned by varying the ZnS NPs content. In vitro cytotoxicity assays suggested that the introduction of ZnS NPs added little cytotoxicity to the PVP/PDMAA hydrogel and all the hydrogel nanocomposites exhibited minimal cytotoxicity towards common cells. The hydrogel nanocomposites implanted in rabbit eyes can be well tolerated over 3 weeks. Hence, the high RI ZnS/PVP/PDMAA hydrogel nanocomposites with adjustable RIs developed in this work might potentially be a candidate material for artificial corneal implants.

  13. The filtering, clear-cornea diathermal keratostomy: a minor Danish multicenter study

    DEFF Research Database (Denmark)

    Kessing, S.V.; Nissen, O.I.; Thygesen, J.;

    2008-01-01

    to start their consecutive IDK series. The data were analyzed centrally. Injection of preoperative, subconjunctival doses of mitomycin C (MMC) was recommended according to risk-of-failure. A total of 54 eyes from 48 patients with advanced and complicated glaucomas (mean age 65 y) and preoperative mean...

  14. Iontophoretic Delivery of Riboflavin into the Rabbit Cornea:a Primary Study

    Institute of Scientific and Technical Information of China (English)

    Na Li; Xiujun Peng; Zhengjun Fan; Yu Xia

    2014-01-01

    Purpose:.To determine the penetrability of riboflavin into the corneal stroma by iontophoresis and to compare the perme-ability effects of different solvents. Methods:.Twenty rabbits were randomly divided into four groups:.a group that received 0.1% riboflavin-balanced salt solution (BSS) by iontophoresis, a group that received 0.1%riboflavin-saline solution by iontophoresis,.a group that re-ceived 0.1% riboflavin-distilled water solution by iontophore-sis, and a control group that received classical riboflavin in-stillation after corneal de-epithelialization..The degree of yel-lowing of the de-epithelialized corneal stromal button from each rabbit was compared. Results:.The yellow color scores for the corneal stromal but-tons in the three iontophoresis groups were compared with those of control group..Iontophoretic delivery of a 0.1% ri-boflavin-distilled water solution yielded similar yellow changes in the corneal stromal button when compared with classical ri-boflavin instillation after de-epithelialization..However,.the other two solvents did not sufficiently enhance the permeabili-ty of riboflavin. Conclusion:.Riboflavin can effectively penetrate into the corneal stroma to saturation levels by iontophoresis..Using distilled water as the solvent can promote penetrability.. (Eye Science 2014; 29:30-35).

  15. Polymerase Chain Reaction Identification of a Hymenopteran Insect in the Cornea: a Case Report

    Directory of Open Access Journals (Sweden)

    Hsien-Chung Lin

    2006-03-01

    Full Text Available The type of corneal injuries associated with insect encounters is related to the composition of the foreign body. However, previous reports on corneal foreign bodies as insects were rarely based on scientific evidence. Here, we report on a 49-year-old male who was stung in his left eye by an unknown insect. Emergent keratotomy was performed to remove the embedded corneal foreign body. The removed foreign body was observed under light microscopy, and a fragment of insect was suspected. The sample was sent for molecular analysis. The polymerase chain reaction product was sequenced, subjected to a BLAST search, and identified as an ichneumonoid member of the insect order Hymenoptera.

  16. A Review of Collagen Cross-Linking in Cornea and Sclera

    Directory of Open Access Journals (Sweden)

    Xiao Zhang

    2015-01-01

    Full Text Available Riboflavin/UVA cross-linking is a technique introduced in the past decades for the treatment of keratoconus, keratectasia, and infectious keratitis. Its efficacy and safety have been investigated with clinical and laboratory studies since its first clinical application by Wollensak for the treatment of keratoconus. Although its complications are encountered during clinical practice, such as infection inducing risk, minimal invasion merits a further investigation on its future application in clinical practice. Recently, collagen cross-linking in sclera shows a promising prospect. In present study, we summarized the representative studies describing the clinical and laboratory application of collagen cross-linking published in past decades and provided our opinion on the positive and negative results of cross-linking in the treatment of ophthalmic disorders.

  17. Filamentous fungal infections of the cornea: a global overview of epidemiology and drug sensitivity.

    Science.gov (United States)

    Kredics, László; Narendran, Venkatapathy; Shobana, Coimbatore Subramanian; Vágvölgyi, Csaba; Manikandan, Palanisamy

    2015-04-01

    Fungal keratitis is a serious suppurative, usually ulcerative corneal infection which may result in blindness or reduced vision. Epidemiological studies indicate that the occurrence of fungal keratitis is higher in warm, humid regions with agricultural economy. The most frequent filamentous fungal genera among the causal agents are Fusarium, Aspergillus and Curvularia. A more successful therapy of fungal keratitis relies on precise identification of the pathogen to the species level using molecular tools. As the sequence analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA gene cluster (rDNA) is not discriminative enough to reveal a species-level diagnosis for several filamentous fungal species highly relevant in keratitis infections, analysis of other loci is also required for an exact diagnosis. Molecular identifications may also reveal the involvement of fungal species which were not previously reported from corneal infections. The routinely applied chemotherapy of fungal keratitis is based on the topical and systemic administration of polyenes and azole compounds. Antifungal susceptibility testing of the causal agents is of special importance due to the emergence and spread of resistance. Testing the applicability of further available antifungals and screening for new, potential compounds for the therapy of fungal keratitis are of highlighted interest.

  18. Toxic endothelial cell destruction of the cornea after routine extracapsular cataract surgery.

    Science.gov (United States)

    Breebaart, A C; Nuyts, R M; Pels, E; Edelhauser, H F; Verbraak, F D

    1990-08-01

    Eighteen patients developed an acute corneal decompensation following normal intraocular surgery (cataract extraction in 17 patients), characterized by star-shaped endothelial folds, a twofold increase in corneal thickness, and a visual acuity of counting fingers during several postoperative days. In some cases, there was an additional iritis and transient hypotony. There was no effect of topical and/or subconjunctival corticosteroids on the course of the decompensation. Endothelial morphometric analysis showed a mean endothelial cell loss of 72%. Endothelial wound healing, as determined by coefficient of variation and percentage hexagonals, stabilized 6 months postoperatively. We coined the term toxic endothelial cell destruction for this syndrome. Epidemiological evaluation revealed the toxic endothelial cell destruction syndrome to be linked with the 10-fold increase of a detergent solution in the ultrasonic bath for cleaning the surgical instruments.

  19. Bacterial transmission from contact lenses to porcine corneas : An ex vivo study

    NARCIS (Netherlands)

    Vermeltfoort, PBJ; van Kooten, TG; Bruinsma, GM; Hooymans, AMM; van der Mei, HC; Busscher, HJ

    2005-01-01

    PURPOSE. To quantify the transmission to ex vivo porcine eyes of Staphylococcus aureus 835 and Pseudomonas aeruginosa 3 from three types of contact lenses - one daily wear and two extended wear - differing in hydrophobicity and roughness. METHODS. One daily wear lens (etafilcon) and two extended-wea

  20. Inflammation Modulatory Protein TSG-6 for Chemical Injuries to the Cornea

    Science.gov (United States)

    2016-10-01

    flush + IV TSG-6 (0.2mg per time point) = 16 Lewis rats total • IV Injection time points: 1. Immediately following injury 2. 6 hours after injury 3...over time in order to further research in the development of a novel therapy with the anti-inflammatory protein TNF-stimulating gene 6 (TSG-6). TSG-6...within neutrophil granules. Real-time PCR (RT-PCR) was used to evaluate mRNA expression levels of cytokines, chemokines, and genes involved in