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Sample records for central corneal thickness

  1. Clinical significance of central corneal thickness and comparison of central corneal thickness

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    Özgür Çakıcı

    2014-03-01

    Full Text Available Significance of central corneal thickness has been increasing in ophthalmology practice. It is an important clinical evaluation tool especially prior to refractive surgery and in diagnosis of glaucoma and keratoconus. Refractive surgery is planned according to preoperative central corneal thickness measurements. Besides, in order to determine actual intraocular pressure, central corneal thickness is measured and corrected eye pressure is obtained. Today, devices used in measurement of central corneal thickness do the measurement according to two principles. First and relatively older method is ultrasonic method. Optic method is the second and more recent method. In daily practice, the most commonly used clinical method in measurement of central corneal thickness is ultrasound pachymeter. However, this measurement technique requires contact between cornea and probe and gives thinner measurement results compared to the methods that use optic principle. Recently, several technologic methods based on optics have been put in use; they provide advantages of non-contact technique and objective determination of central corneal thickness. Of these methods, most commonly used include Specular Microscopy, Optical coherence tomography, Laser Doppler Interferometry, Optical low coherence reflectometry pachymetry, Optic based topographic mapping (also called screening section pachymetry and Pentacam. In this article, it was aimed to evaluate importance of central corneal thickness in clinical use and compare measurement methods. J Clin Exp Invest 2014; 5 (1: 153-158

  2. Central Corneal Thickness in Adult Chinese

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The central corneal thickness (CCT) in age 48 years or less of Chinese was characterized and its relationship with gender, age, refraction and intraocular pressure (IOP) was investigated.Right eyes of 1669 participants were included in this study (880 men, 52.7 % and 789 women,47.3 %). Mean age of the samples was 23.8±5.9 years. After the examination of corneal topography and refraction, Goldman applanation tonometry was carried out by one physician. Tonometric values were the mean of three consecutive readings. Subsequently, another physician carried out ultrasonic pachymetry with the DGH 2000 AP ultrasonic pachymeter. Six measuremen ts were made at the center of the cornea of each eye. The mean value was used for analysis. The results showed that mean CCT of male participants was 551.33± 34. 62 μm, 5.79 μm more than that of female participants. Linear regression analyses revealed that CCT was negatively related with age only in female and no association was found between refractive status and CCT. IOP was positively related to CCT, and there was a difference in IOP of 1.5 mmHg (1 mmHg=0. 133 kPa) per 100 μm difference in CCT. Ocular hypertension group was prone to have thicker cornea than average. The results indicated that in adult Chinese CCT tended to decrease with aging in female only. IOP measured by Goldmann tonometry was positively related with CCT so that CCT should be measured along with IOP.

  3. Anatomical characterization of central, apical and minimal corneal thickness

    Institute of Scientific and Technical Information of China (English)

    Federico; Saenz-Frances; Martha; Cecilia; Bermúdez-Vallecilla; Lara; Borrego-Sanz; Luis; Jaez; J; osé; Marìa; Martinez-de-la-Casa; Laura; Morales-Fernandez; Enrique; Santos-Bueso; Julián; Garcia-Sanchez; Julián; Garcia-Feijoo

    2014-01-01

    ·AIM: To anatomically locate the points of minimum corneal thickness and central corneal thickness(pupil center) in relation to the corneal apex.·METHODS: Observational, cross-sectional study, 299 healthy volunteers. Thickness at the corneal apex(AT),minimum corneal thickness(MT) and corneal thickness at the pupil center(PT) were determined using the pentacam. Distances from the corneal apex to MT(MD)and PT(PD) were calculated and their quadrant position(taking the corneal apex as the reference) determined:point of minimum thickness(MC) and point of central thickness(PC) depending on the quadrant position. Two multivariate linear regression models were constructed to examine the influence of age, gender, power of the flattest and steepest corneal axes, position of the flattest axis, corneal volume(determined using the Pentacam)and PT on MD and PD. The effects of these variables on MC and PC were also determined in two multinomial regression models.·RESULTS: MT was located at a mean distance of 0.909 mm from the apex(79.4% in the inferior-temporal quadrant). PT was located at a mean distance of 0.156 mm from the apex. The linear regression model for MD indicated it was significantly influenced by corneal volume(B =-0.024; 95% CI:-0.043 to-0.004). No significant relations were identified in the linear regression model for PD or the multinomial logisticregressions for MC and PC.·CONCLUSION: MT was typically located at the inferiortemporal quadrant of the cornea and its distance to the corneal apex tended to decrease with the increment of corneal volume.

  4. Analysis of the horizontal corneal diameter, central corneal thickness, and axial length in premature infants

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    Ozdemir Ozdemir

    2014-08-01

    Full Text Available Purpose: To determine the horizontal corneal diameter, central corneal thickness, and axial length in premature infants. Methods: Infants with a birth weight of less than 2,500 g or with a gestation period of less than 36 weeks were included in the study. Infants with retinopathy of prematurity (ROP were allocated to Group 1 (n=138, while those without ROP were allocated to Group 2 (n=236. All infants underwent a complete ophthalmologic examination, including corneal diameter measurements, pachymetry, biometry, and fundoscopy. Between-group comparisons of horizontal corneal diameter, central corneal thickness, and axial lengths were performed. Independent sample t-tests were used for statistical analysis. Results: Data was obtained from 374 eyes of 187 infants (102 female, 85 male. The mean gestational age at birth was 30.7 ± 2.7 weeks (range 25-36 weeks, the mean birth weight was 1,514 ± 533.3 g (range 750-1,970 g, and the mean postmenstrual age at examination was 40.0 ± 4.8 weeks. The mean gestational age and the mean birth weight of Group 1 were statistically lower than Group 2 (p0.05. Conclusions: The presence of ROP in premature infants does not alter the horizontal corneal diameter, central corneal thickness, or axial length.

  5. The relationship between central corneal thickness and corneal curvature in adult Nigerians

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    E. Iyamu

    2011-12-01

    Full Text Available Purpose: The aim of this study was to provide average values for central corneal thickness (CCT and corneal curvature (CC and also to determine a regression model for the relationship between CCT and CC in adult Nigerians without glaucoma.Methods: A total of 95 subjects consisting of 56 males and 39 females aged between 20 and 69 years with mean age of 47.1 ± 14.1 years were recruited for the study. Central corneal thickness was measured by ultrasound pachymetry (SW-1000P ultrasound pachymeter, Tianjin Suowei Electronic Technology, China and corneal curvature was measured by keratometry (Bausch & Lomb keratometer H-135A, USA.Results: The average values of 550.1 ± 33.1µm and 43.0 ± 1.1 D were obtained for CCT and CC respectively. CCT significantly correlated with age (p=0.01, and the regression model predicts a decrease of 6.0 µm in CCT per decade. No significant association was found between CC and age (p=0.56. Also, no significant association was found between CCT and CC (p=0.07. Female subjects had significantly steeper corneas than their male counterparts.Conclusion: Central corneal thickness decreases with increasing age. Neither CCT nor age appear to be significantly correlated with corneal curvature. (S Afr Optom 2011 70(1 44-50

  6. Quantitative trait loci associated with murine central corneal thickness

    OpenAIRE

    Lively, Geoffrey D.; Koehn, Demelza; Hedberg-Buenz, Adam; Wang, Kai; Anderson, Michael G.

    2010-01-01

    The cornea is a specialized transparent tissue responsible for refracting light, serving as a protective barrier, and lending structural support to eye shape. Given its importance, the cornea exhibits a surprising amount of phenotypic variability in some traits, including central corneal thickness (CCT). More than a mere anatomic curiosity, differences in CCT have recently been associated with risk for glaucoma. Although multiple lines of evidence support a strong role for heredity in regulat...

  7. Central corneal thickness and intraocular pressure in premature infants.

    Science.gov (United States)

    Sekeroglu, Mehmet Ali; Hekimoglu, Emre; Petricli, İkbal Seza; Karakaya, Jale; Ozcan, Beyza; Yucel, Husniye; Kavurt, Aysen Sumru; Bas, Ahmet Yagmur

    2015-12-01

    To evaluate the central corneal thickness (CCT) and intraocular pressure (IOP) of premature infants and to document correlation of them with gestational age, chronological age, and birth weight of infants. Using a hand-held applanation tonometer and a portable pachymeter, IOP and CCT of 170 premature infants were measured just before initial retinopathy of prematurity screening examination and re-measured 4 weeks after the first visit. The CCT and IOP were positively correlated during the first (r = 0.616, p premature infants with a smaller gestational age were found to be higher (p Premature infants with smaller gestational age have higher CCT and IOP values when compared to older infants. These values tend to become lower 4 weeks after the first examination as infants become older. The CCT and IOP were positively correlated with each other and both were negatively correlated with gestational age, chronological age, and birth weight during first and second visits. PMID:26286757

  8. The Heritability of Glaucoma-Related Traits Corneal Hysteresis, Central Corneal Thickness, Intraocular Pressure, and Choroidal Blood Flow Pulsatility

    OpenAIRE

    Freeman, Ellen E.; Roy-Gagnon, Marie-Hélène; Descovich, Denise; Massé, Hugues; Mark R. Lesk

    2013-01-01

    Purpose The purpose of this work was to investigate the heritability of potential glaucoma endophenotypes. We estimated for the first time the heritability of the pulsatility of choroidal blood flow. We also sought to confirm the heritability of corneal hysteresis, central corneal thickness, and 3 ways of measuring intraocular pressure. Methods Measurements were performed on 96 first-degree relatives recruited from Maisonneuve-Rosemont Hospital in Montreal. Corneal hysteresis was determined u...

  9. Effect of fluidics on corneal endothelial cell density, central corneal thickness, and central macular thickness after phacoemulsification with torsional ultrasound

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    Sudeep Das

    2015-01-01

    Full Text Available Aim: To study the relative effects of high and low fluidic parameters on endothelial cell density (ECD, central corneal thickness (CCT, and central macular thickness (CMT after phacoemulsification with torsional ultrasound. Settings and Design: Prospective, randomized clinical trial based on a tertiary eye hospital. Subjects and Methods: The study included 65 patients in each group. Patients were randomized to either the high or the low flow group using a computerized random number table. The study was patient and examiner masked. All patients underwent phacoemulsification with torsional ultrasound. Visual acuity, ECD, CCT, and CMT were measured for all patients preoperatively at 2 weeks and 6 weeks postoperatively. Statistical Analysis Used: The Shapiro–Wilks test was used to assess the normality of the data. Mann–Whitney U-test with the P value set at 0.05 was used to compare the two groups. Results: Cumulative dissipated energy was significantly higher in the low flow group (16.44 ± 9.07 vs. 11.74 ± 6.68; P = 0.002. No statistically significant difference was noted between the two groups in the ECD, CCT, CMT, or corrected distance visual acuity at the end of 6 weeks. Conclusions: No significant difference was noted in the postoperative outcome between high and low flow groups. Parameters can be modified to suit the surgeon's preference, as both high and low flow parameters were found to have comparable postoperative outcomes.

  10. Central Corneal Thickness Measurement by Ultrasound versus Orbscan II

    Science.gov (United States)

    Faramarzi, Amir; Ziai, Hossein

    2008-01-01

    Purpose To compare Orbscan II and ultrasonic pachymetry for measurement of central corneal thickness (CCT) in eyes scheduled for keratorefractive surgery. Methods CCT was measured using Orbscan II (Bausch & Lomb, USA) and then by ultrasonic pachymetry (Tomey SP-3000, Tomey Ltd, Japan) in 100 eyes of 100 patients with no history of ocular surgery scheduled for excimer laser refractive surgery. Results Mean CCT was 544.7±35.5 (range 453–637) μm by ultrasonic pachymetry versus 546.9±41.6 (range 435–648) μm measured by Orbscan II applying an acoustic factor of 0.92 (P=0.14). The standard deviation of measurements was greater with Orbscan pachymetry but the difference was not statistically significant. Conclusion CCT measurements by Orbscan II (applying an acoustic factor) and by ultrasonic pachymetry are not significantly different; however, when CCT readings by Orbscan II are in the lower range, it is advisable to recheck the measurements using ultrasonic pachymetry. PMID:23479527

  11. The heritability of glaucoma-related traits corneal hysteresis, central corneal thickness, intraocular pressure, and choroidal blood flow pulsatility.

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    Ellen E Freeman

    Full Text Available PURPOSE: The purpose of this work was to investigate the heritability of potential glaucoma endophenotypes. We estimated for the first time the heritability of the pulsatility of choroidal blood flow. We also sought to confirm the heritability of corneal hysteresis, central corneal thickness, and 3 ways of measuring intraocular pressure. METHODS: Measurements were performed on 96 first-degree relatives recruited from Maisonneuve-Rosemont Hospital in Montreal. Corneal hysteresis was determined using the Reichert Ocular Response Analyser. Central corneal thickness was measured with an ultrasound pachymeter. Three measures of intraocular pressure were obtained: Goldmann-correlated and corneal compensated intraocular pressure using the Ocular Response Analyser, and Pascal intraocular pressure using the Pascal Dynamic Contour Tonometer. The pulsatility of choroidal blood velocity and flow were measured in the sub-foveolar choroid using single-point laser Doppler flowmetry (Oculix. We estimated heritability using maximum-likelihood variance components methods implemented in the SOLAR software. RESULTS: No significant heritability was detected for the pulsatility of choroidal blood flow or velocity. The Goldman-correlated, corneal compensated, and Pascal measures of intraocular pressure measures were all significantly heritable at 0.94, 0.79, and 0.53 after age and sex adjustment (p = 0.0003, p = 0.0023, p = 0.0239. Central corneal thickness was significantly heritable at 0.68 (p = 0.0078. Corneal hysteresis was highly heritable but the estimate was at the upper boundary of 1.00 preventing us from giving a precise estimate. CONCLUSION: Corneal hysteresis, central corneal thickness, and intraocular pressure are all heritable and may be suitable as glaucoma endophenotypes. The pulsatility of choroidal blood flow and blood velocity were not significantly heritable in this sample.

  12. Central corneal thickness vs Goldman´ tonometry. Study in suspecting patients of Glaucoma.

    OpenAIRE

    Elsa E. Cabeza Martínez; Damaris Peralta Palmero; Elena Triana Gutiérrez

    2010-01-01

    Measuring of the central corneal thickness through ultrasonic pachymetry, in several opportunities can contribute to diagnose glaucoma. The main objective of this research was to determine, the central corneal thickness in suspecting patients of having glaucoma.to check if it makes influence while taking the intraocular pressure with the Tonometer of Goldman, 328 eyes were studied out of the 164 patients who attended the glaucoma provincial appointment as suspecting of suffering from this pat...

  13. Comparison of Central Corneal Thickness Measurements by Ultrasonic Pachymetry and Orbscan II Corneal Topography and Evaluation of Ultrasonic Pachymetry Repeatability

    OpenAIRE

    Semra Tiryaki Demir; Mahmut Odabaşı; Mehmet Ersin Oba; Ayşe Burcu Dirim; Efe Can; Orhan Kara

    2014-01-01

    Objectives: Comparison of central corneal thickness (CCT) measurements by ultrasonic pachymetry and Orbscan II corneal topography and evaluation of ultrasonic pachymetry repeatability for same observer. Materials and Methods: The study included 132, 82, and 80 eyes of 66 patients with primary open-angle glaucoma (POAG), 41 patients with ocular hypertension (OHT), and 40 controls, respectively. All subjects were subjected to routine ophthalmic examination. Orbscan II (Bausch&Lomb) ...

  14. Effect of topical dorzolamide on rabbit central corneal thickness

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    Almeida Jr. G.C.

    2006-01-01

    Full Text Available Our objective was to study the effect of dorzolamide on corneal hydration in an 18-week controlled experiment using ultrasonic pachymetry. Twenty-eight male rabbits were divided randomly into four groups. The 7 rabbits in each group received eye drops containing either 2% (w/v dorzolamide or placebo in their right eye, or in their left eye. The 2% dorzolamide rabbits were treated every 8 h. Fellow eyes are defined as eyes which did not receive either dorzolamide or placebo. The study was blind for both the person who applied the drug and the one who performed the pachymetry. The effect of treatments is reported on the basis of the percentage of pachymetric variation compared to the measurement made before drug application. There was no significant difference (P = 0.061 in pachymetric variation between dorzolamide (-4.42 ± 11.71% and placebo (2.48 ± 9.63%. However, there was a significant difference (P = 0.0034 in pachymetric variation between the dorzolamide fellow eyes (-7.56 ± 10.50% and the placebo (-4.42 ± 11.71%. In conclusion, dorzolamide did not increase the corneal thickness in rabbits.

  15. Evaluation of Central Corneal Thickness Measurements by Optical Low Coherence Reflectometry and Contact Ultrasonic Pachymeter

    OpenAIRE

    Kocatürk, Tolga; Erkan, Erol; Çakmak, Harun; Kurt Ömürlü, İmran; Dayanır, Volkan

    2015-01-01

    AbstractObjective: The aim is to compare the central corneal thickness measurements by optical low-coherence reflectometry and contact ultrasonic pachymeter in patients with pseudoexfoliation syndrome, pseudoexfoliation glaucoma, primary open-angle glaucoma as well as healthy subjects.Materials and Methods: We have made a survey of the data of the patients with glaucoma who had been followed for ten years at the Department of Ophthalmology. 148 eyes of 76 patients who had central corneal thic...

  16. Corneal thickness in glaucoma.

    Science.gov (United States)

    De Cevallos, E; Dohlman, C H; Reinhart, W J

    1976-02-01

    The central corneal stromal thickness of patients with open angle glaucoma, secondary glaucoma (the majority aphakic), or a history of unilateral acute angle closure glaucoma were measured and compared with the stromal thickness of a group of normal patients. In open angle glaucoma, there was a small but significant increase in the average stromal thickness. This thickness increase was, in all likelihood, due to an abnormal function of the endothelium in this disease since the level of the intraocular pressure did not seem to be a factor. There was no correlation between stromal thickness and duration of the glaucoma or type of anti-glaucomatous medication. Most cases of secondary glaucome, controlled medically or not, had markedly increased corneal thickness, again, most likely, due to endothelial damage rather than to level of intraocular pressure. After an angle closure attack, permanent damage to the cornea was found to be rare. PMID:1247273

  17. Central Corneal Thickness Measurement by Ultrasound versus Orbscan II

    Directory of Open Access Journals (Sweden)

    Amir Faramarzi

    2008-12-01

    Full Text Available

    PURPOSE: To compare Orbscan II and ultrasonic pachymetry for measurement of central corneal thickness (CCT in eyes scheduled for keratorefractive surgery. METHODS: CCT was measured using Orbscan II (Bausch & Lomb, USA and then by ultrasonic pachymetry (Tomey SP-3000, Tomey Ltd, Japan in 100 eyes of 100 patients with no history of ocular surgery scheduled for excimer laser refractive surgery. RESULTS: Mean CCT was 544.7±35.5 (range 453-637 µm by ultrasonic pachymetry versus 546.9±41.6 (range 435-648 µm measured by Orbscan II applying an acoustic factor of 0.92 (P=0.14. The standard deviation of measurements was greater with Orbscan pachymetry but the difference was not statistically significant. CONCLUSION: CCT measurements by Orbscan II (applying an acoustic factor and by ultrasonic pachymetry are not significantly different; however, when CCT readings by Orbscan II are in the lower range, it is advisable to recheck the measurements using ultrasonic pachymetry.

  1. Comparison of Central Corneal Thickness Measurements Obtained with Ultrasonic Pachymetry and Spectral Domain Anterior Segment OCT

    OpenAIRE

    Kirikkaya, Esin Tunca; Akyuz Unsal, Ayşe İpek; Dogramaci, Mahmut

    2014-01-01

    Aim: To compare central corneal thickness (CCT) measurements obtained with Ultrasonic Pachymetry (USP) and Anterior Segment Optical Coherence Tomography (AS-OCT).Methods: Seventy eight eyes of thirty nine volunteers between 40-60 ages were recruited in this study. Best corrected visual acuity (BCVA), intraocular pressure (IOP) measurements, anterior and posterior segment biomicroscopic examinations of all volunteers were performed. CCT measurements were evaluated with Nidek  UP and Zeiss Cirr...

  2. Candidate gene study to investigate the genetic determinants of normal variation in central corneal thickness

    OpenAIRE

    Dimasi, David P.; Kathryn P Burdon; Hewitt, Alex W; Savarirayan, Ravi; Healey, Paul R.; Mitchell, Paul; Mackey, David A.; Craig, Jamie E

    2010-01-01

    Purpose The genetic component underlying variation in central corneal thickness (CCT) in the normal population remains largely unknown. As CCT is an identified risk factor for open-angle glaucoma, understanding the genes involved in CCT determination could improve our understanding of the mechanisms involved in this association. Methods To identify novel CCT genes, we selected eight different candidates based on a range of criteria. These included; aquaporin 1 (AQ1), aquaporin 5 (AQ5), decori...

  3. Assessment of the central corneal thickness and intraocular pressure in premature and full-term newborns

    OpenAIRE

    Muslubas, Isil Bahar Sayman; Oral, Ayse Yesim Aydın; Cabi, Cemalettin; Caliskan, Sinan

    2014-01-01

    Purpose: To assess the central corneal thickness (CCT) and intraocular pressure (IOP) in premature and full-term newborns. Materials and Methods: In this study, we evaluated measurements of CCT and IOP in 45 premature and 45 full-term newborns. IOP was determined with topical anesthesia using a Tono-Pen AVIA, applanation tonometer and a wire lid retractor in premature newborns undergoing screening for retinopathy. Full-term newborns were used as a control group. CCT was determined with a port...

  4. Comparison of Spectral Domain Optical Coherence Tomography and Ultrasonic Pachymetry for Assessment of Central Corneal Thickness

    OpenAIRE

    G. Ertuğrul Mirza

    2014-01-01

    Objectives: The aim of this study was to determine if there is a difference in central corneal thickness (CCT) measurements obtained by Cirrus spectral domain optical coherence tomography (SD-OCT) and ultrasonic pachymetry in healthy individuals. Materials and Methods: The study included 50 healthy consecutively selected individuals without ocular or systemic disease. CCT was first measured using OCT, and then using ultrasonic pachymetry. Results: Mean age of the participants was ...

  5. Central corneal thickness and anterior chamber depth measurement by Sirius® Scheimpflug tomography and ultrasound

    OpenAIRE

    Jorge J; Rosado JL; Díaz-Rey JA; González-Méijome JM

    2013-01-01

    J Jorge,1 JL Rosado,2 JA Díaz-Rey,1 JM González-Méijome11Clinical and Experimental Optometry Research Laboratory, Center of Physics (Optometry), School of Sciences, University of Minho, Braga, 2Opticlinic, Lisboa, PortugalBackground: The purpose of this study was to compare the accuracy of the new Sirius® Scheimpflug anterior segment examination device for measurement of central corneal thickness (CCT) and anterior chamber depth (ACD) with that of CCT ...

  6. Central Corneal Thickness Measurements in Nonarteritic Anterior Ischemic Optic Neuropathy Patients: A Controlled Study

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    Haneen Jabaly-Habib

    2014-01-01

    Full Text Available Purpose. To measure central corneal thickness (CCT in patients with history of nonarteritic anterior ischemic optic neuropathy (NAION. Patients and Methods. Patients older than 40 years with a history of NAION (group 1 were prospectively evaluated including full eye examination and central corneal thickness (CCT pachymetry. Patients with a history of intraocular surgery, corneal disease, glaucoma, and contact lens wear were excluded. Measurements were also performed in a gender and age matched control group (group 2. Results. Thirty-one eyes of 31 NAION patients in group 1 were included and 30 eyes of 30 participants in group 2. There were 15 men in group 1 and 9 in group 2 P=0.141, and mean age of the patients was 59±10 years in group 1 versus 61±11 years in group 2 P=0.708. Mean CCT was 539±30 microns in group 1 and 550±33 microns in group 2 P=0.155. Conclusion. Patients with NAION have no special characteristic of CCT in contrast to the crowded optic disc known to be a significant anatomic risk factor for NAION. More studies should be carried out to investigate CCT and other structure related elements in NAION patients.

  7. Importance of Corneal Thickness

    Science.gov (United States)

    ... News About Us Donate In This Section The Importance of Corneal Thickness email Send this article to ... is important because it can mask an accurate reading of eye pressure, causing doctors to treat you ...

  8. Comparison of central corneal thickness measurements between anterior chamber-optical coherence tomography and ultrasonic pachymeter

    International Nuclear Information System (INIS)

    Objective: To assess the agreement of central corneal thickness (CCT) measured by anterior chamber-optical coherence tomography (AC-OCT) and ultrasonic pachymeter and provide an objective basis for clinical application of AC-OCT. Methods: CCT of 150 college student volunteers (300 eyes) measured by two devices were obtained. The data was analyzed by paired t test and Pearson correlation analysis. Bland-Altman plot and Mountain plot were used to assess the agreement. Results: The mean CCT values were (530.05 ± 33.611) μm measured by AC-OCT and (543.68 ± 35.088) μm measured by ultrasonic pachymeter. Regression analysis showed a high correlation between the values obtained by both devices (r=0.960, P<0.001). Compared with AC-OCT, ultrasonic pachymeter overestimated the CCT by a mean of 13.62 μm. The two modalities had incomparable results. Conclusion: It is important to be noted in clinical practice that the measurements acquired by these two modalities are not directly interchangeable. However, the CCT measurements by the AC-OCT and ultrasonic pachymeter are highly correlated. AC-OCT is an effective method to observe the changes of the corneal thickness in the long term. (authors)

  9. The Association of Central corneal thickness with Intra-ocular Pressure and Refractive Error in a Nigerian Population

    OpenAIRE

    Eghosasere Iyamu; Misan Memeh

    2008-01-01

    The purpose of this study was to determine the variation of central corneal thickness (CCT) with intraocular pressure (IOP) and spherical equivalent refractive error. A total of thirty-nine (N=39) subjects within 20-75 years with mean age 45.2 ± 15.4 years were used for this study. The central corneal thickness was assessed with the Corneo-Gage plus ultrasonic Pachymeter, the IOP with slit-lamp mounted Goldmann applanation tonometer and refractive status by Protec 2000 autorefractor, phoropte...

  10. Comparison of Central Corneal Thickness and Retinal Nerve Fiber Layer Thickness and Ganglion Cell Complex in Patients with Ocular Hypertension

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    Gamze Mumcu Taşlı

    2013-12-01

    Full Text Available Purpose: To evaluate the correlation of retinal nerve fiber layer thickness (RNFLT with ganglion cell complex and central corneal thickness (CCT measurements in patients with ocular hypertension and healthy subjects. Material and Method: Seventy-six eyes of 38 patients with ocular hypertension and 76 eyes of 38 healthy subjects were included in this study. Both groups were stratified by CCT into 579 µm (p0.05. In the control group, there was no significant correlation between CCT and RNFLT (average, superior average, inferior average measurements (p>0.05. There was no significant correlation between CCT and average, superior average, inferior average ganglion cell complex in both groups. Discussion: Ocular hypertension patients with CCT <550 µm may represent patients who have very early undetected glaucoma. This may in part explain the higher risk of these patients for progression to glaucoma. (Turk J Ophthalmol 2013; 43: 385-90

  11. Central corneal thickness and intraocular pressure in the Cameroonian nonglaucomatous population

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    André Omgbwa Eballe

    2010-07-01

    Full Text Available André Omgbwa Eballe1, Godefroy Koki2, Augustin Ellong2, Didier Owono2, Emilienne Epée2, Lucienne Assumpta Bella2, Côme Ebana Mvogo1, Jeanne Mayouego Kouam21Faculty of Medicine and Pharmaceuticals Sciences, University of Douala; 2Faculty of Medicine and Biomedical Sciences, University of Yaoundé, CameroonAim: We performed a prospective, analytical study from 01 January to 31 March 2009 in the Ophthalmology Unit of the Gyneco-Obstetric and Pediatric Hospital of Yaounde, aiming to determine the profile of central corneal thickness (CCT in the Cameroonian nonglaucomatous black population and its relationship with intraocular pressure (IOP.Results and discussion: Four hundred and eighty-five patients (970 eyes meeting our ­inclusion criteria were selected for this study. The average CCT was 529.29 ± 35.9 µm in the right eye (95% confidence interval [CI]: 526.09–532.49, 528.19 ± 35.9 µm in the left eye (95% CI: 524.99–531.40 and 528.74 ± 35.89 µm in both eyes (95% CI: 526.48–531.00, range 440 to 670 µm. The average IOP was 13.01 ± 2.97 mmHg in both eyes (95% CI: 12.82–13.19. A rise in CCT by 100 µm was followed by an increase in IOP of about 2.8 mmHg (95% CI: 2.3–3.6 for both eyes taken together. Linear regression analysis showed that corneal thickness was negatively correlated with age and IOP was positively related with age.Conclusion: CCT in the Cameroonian nonglaucomatous black population was found to be lower compared with CCT values in Caucasian and Asian populations. On the basis of reference values ranging between 527 and 560 µm, an adjustment of IOP values by a correction factor is required for many Cameroonian patients. This will improve the diagnosis and follow-up of glaucoma by helping to detect true ocular hypertension.Keywords: central corneal thickness, intraocular pressure, Cameroon

  12. Central corneal thickness in black Cameroonian ocular hypertensive and glaucomatous subjects

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    Christelle Domngang Noche

    2010-11-01

    Full Text Available Christelle Domngang Noche1, André Omgbwa Eballe2, Assumpta Lucienne Bella31Innel Medical Center, 2Faculty of Medicine, University of Douala, 3Faculty of Medicine and Biomedical Sciences, University of Yaoundé, CameroonPurpose: To evaluate central corneal thickness (CCT in a black Cameroonian population of ocular hypertensive and glaucomatous subjects.Material and methods: This was a prospective study undertaken with an ultrasonic pachymeter from January 2009 to December 2009 in an eye clinic (INNEL Medical center in Yaoundé, Cameroon.Results: One hundred subjects (200 eyes were enrolled in the study. Sixty subjects were glaucomatous (primary open angle glaucoma, POAG group, and 40 ocular hypertensive (OHT group. The mean age of the sample was 52.60 ± 12.23 years. For the whole sample, CCT was 534.71 ± 37.95 µm in the right eye and 533.61 ± 37.67 µm in the left eye, with no statistically significant difference between the 2 eyes (P = 0.446. CCT in the POAG group was 526.30 ± 37.34 µm in the right eye and 524.90 ± 35.92 µm in the left eye. CCT in the OHT group was 547.32 ± 35.71 µm in the right eye and 546.67 ± 36.85 µm in the left eye. There was a statistically significant difference between CCT of the 2 groups (right eye: P = 0.013; left eye: P = 0.007.Conclusion: Mean CCT of ocular hypertensive subjects was thicker than CCT of glaucomatous ones in our Cameroonian sample. However, in both ocular hypertensive or glaucomatous patients, CCT of black Cameroonians is thinner than that reported in other studies in Caucasian populations.Keywords: central corneal thickness, ocular hypertension, glaucoma, black Cameroonian

  13. The Influence of Type-1 Diabetes Mellitus on Central Corneal Thickness in Children

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    Pınar Yüksekkaya

    2014-12-01

    Full Text Available Objectives: To evaluate the central corneal thickness (CCT in children with diabetes mellitus (DM, to compare the results with those of age- and sex-matched healthy subjects, and to assess the presence of any relationship between the disease-variable parameters and CCT. Materials and Methods: This prospective, cross-sectional study included 138 eyes of 138 subjects. The CCT was measured by ultrasonic pachymetry in 66 children with type-1 DM and in 72 healthy subjects. The effects of the duration of DM, current hemoglobin A1c levels (HbA1c, and fasting blood glucose (FBG levels on CCT were also evaluated. Results: The demographic characteristics of the study and control groups were similar (p>0.05. The average CCT was greater in the study (555.2±38.6 µm than in the control group (547.7±31.5 µm, but the difference was not statistically significant (independent t-test, p=0.211. CCT was also not significantly different in children with diabetes >5 years’ duration (554.6±39.3 µm compared to diabetes ≤5 years’ duration (555.6±38.6 µm (p>0.05, and there was no significant correlation between the CCT- and the DM-related parameters in the study group (p>0.05. Conclusion: Our findings indicate that DM does not affect the corneal thickness in adolescents. We also did not find any significant correlation between disease-related variables and the CCT. (Turk J Ophthalmol 2014; 44: 445-8

  14. Long-term change in central corneal thickness from a glaucoma perspective

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    Nikhil S Choudhari

    2013-01-01

    Full Text Available Aim: To investigate the longitudinal change in central corneal thickness (CCT over 3 years in patients with glaucoma. Materials and Methods: The Chennai Glaucoma Follow-up Study, an offshoot of the Chennai Glaucoma Study, was designed to evaluate the progression of glaucoma. A cohort of participants in the Chennai Glaucoma Study that were suffering from glaucoma or were at a higher risk for glaucoma underwent comprehensive ophthalmic evaluation at the base hospital at 6-month intervals during the years 2004 to 2007. The CCT (average of 10 readings was measured between 11 am and 1 pm on any given day using an ultrasonic pachymeter. Patients with a history of ocular surgery, corneal disease and usage of topical carbonic anhydrase inhibitor were excluded. No patient was a contact lens wearer. Results: One hundred and ninety-six patients (84 male, 112 female met the inclusion criteria. We analyzed data from the right eye. The mean age of the patients was 59.97 ± 9.06 years. Fifty-nine (30.1% of the patients were diabetic. The mean change in CCT (CCT at first patient visit - CCT at last patient visit was 3.46 ± 7.63 μm. The mean change in CCT was 0.75 μm per year (R 2 = 0.00. Age, gender, intraocular pressure at the first patient visit and diabetic status had no significant influence on the magnitude of change in CCT. Conclusion: A carefully obtained CCT reading by a trained examiner need not be repeated for at least 3 years as long as the ocular and systemic factors known to affect the measurement of CCT are constant.

  15. Comparison of Pre-operative Central Corneal Thickness in Pediatric Cataract Cases versus Normal

    International Nuclear Information System (INIS)

    Objective: To compare the pre-operative central corneal thickness (CCT) in paediatric cataract patients with reference to normal control group. Study Design: A case control study. Place and Duration of Study: Paediatric Ophthalmology Clinic of Al-Shifa Trust Eye Hospital (ASTEH), Rawalpindi, from November 2009 to May 2010. Methodology: The study included 116 subjects with equal number of cases and controls. Demographic profile of all the subjects was noted followed by history and detailed ophthalmic examination. CCT was measured using an ultrasonic pachymeter (model Pac Scan 300). The mean of three measurements from the central cornea were recorded in microns. Results were analyzed using SPSS version 17.0. Results: Mean CCT values of the cases was 566.83 +- 37.646 microns while the control group had a mean CCT of 535.81 +- 24.466 microns. Difference between the CCT values of the two groups was highly significant (p < 0.001). Conclusion: Eyes with congenital cataracts have greater CCT values as compared to normal paediatric population. This factor must be kept in mind while interpreting intra-ocular pressure in such patients. (author)

  16. Changes in central corneal thickness and endothelial cell count pediatric cataract surgery

    International Nuclear Information System (INIS)

    To evaluate the mean changes in Central Corneal Thickness (CCT) and Endothelial Cell Count (ECC) in eyes after pediatric cataract surgery with foldable intraocular lens using scleral tunnel incision micro-surgical technique. Study Design: Qausi experimental study. Place and Duration of Study: Department of Pediatric Ophthalmology and Strabismus, Al-Shifa Trust Eye Hospital, Rawalpindi, from May 2011 to March 2012. Methodology: Fifty-two eyes of 37 children with pediatric cataract were included in the study. Extracapsular Cataract Extraction (ECE) with foldable Intra Ocular Lens (IOL) implantation using sclera tunnel incision was performed in all children. Endothelial Cell Count (ECC) and Central Corneal Thickness (CCT) were recorded before surgery and 1 month, 3 months and 6 months after surgery and the effect of currently practiced surgical technique on ECC and CCTwas evaluated. Results: The mean age at the time of surgery was 8.8 ± 2.7 years (range: 4 to 15 years). The postoperative ECC and CCT were significantly different from the pre-operative values. Mean pre-operative ECC was 3175.3 ± 218.4 cell/mm2 and in first postoperative month the mean ECC was 3113.4 ± 210.8 cell/mm2 (p<0.0001). In the 3rd and 6th month postoperative means ECC were 3052 ± 202.5 cell/mm2 (p<0.0001) and 3015 ±190.6 cell/mm2 (p<0.0001), respectively. The mean cell loss at first postoperative month was 1.95% and at 3rd and 6th postoperative month were 3.9% and 5.05%, respectively. Mean pre-operative CCT was 514 ± 49.9 micro m and first postoperative mean CCT after 1 month was 524.1 ± 25 micro m (p = 0.084). After the 3rd and 6th months postoperative, mean CCT were 527.3 ± 24.6 micro m, and 530 ± 24.5 micro m, respectively. Third and 6th months postoperative means were significantly higher than baseline CCT, p = 0.024 and 0.007, respectively. Conclusion: Endothelial cell loss with closed chamber micro-surgical technique using scleral tunnel incision is within acceptable limits and

  17. Corneal thickness and endothelial density before and after cataract surgery

    OpenAIRE

    Ventura, A.; Walti, R; Bohnke, M

    2001-01-01

    BACKGROUND/AIMS—Deturgescence of the corneal stroma is controlled by the pumping action of the endothelial layer and can be monitored by measurement of central corneal thickness (pachymetry). Loss or damage of endothelial cells leads to an increase in corneal thickness, which may ultimately induce corneal decompensation and loss of vision. Little is known about the effect of moderate reductions in endothelial cell number on the thickness of the corneal stroma. This study aimed to investigate ...

  18. The effects of delivery type and gender on intraocular pressure and central corneal thickness in newborns

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    Zeynep Gursel Ozkurt

    2016-04-01

    Full Text Available ABSTRACT Purpose: To analyze intraocular pressure (IOP and central corneal thickness (CCT in newborns during the first 12 h of life. Methods: Forty-three newborns born by vaginal delivery (VD and 30 newborns born by cesarean section (CS were evaluated. IOP and CCT were measured using Tono-Pen and handheld pachymeter, respectively, at both the 5th minute after delivery and at the 12th h of life. Results: The mean IOP for the VD group was significantly higher than that of the CS group at both the 5th minute and 12th h (p =0.042 and p =0.018, respectively. In both groups, the IOP decreased by the 12th h, but the decrease was only significant for the CS group (p =0.020. The decrease in CCT over the 12 h was significant for both groups (p <0.001. In the VD and CS groups, the IOP values of the males were significantly higher than those of the females at the fifth minute only (p =0.024 and p =0.043, respectively. No other values were significantly different between the genders. Conclusions: Newborn IOP is affected by the mode of delivery and gender. A higher IOP was found in vaginally delivered newborns than in CS newborns for at least 12 h postpartum. CCT showed a significant decline within 12 h. Male newborns have significantly higher IOP values in the first minutes of life.

  19. Comparison of Spectral Domain Optical Coherence Tomography and Ultrasonic Pachymetry for Assessment of Central Corneal Thickness

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    G. Ertuğrul Mirza

    2014-08-01

    Full Text Available Objectives: The aim of this study was to determine if there is a difference in central corneal thickness (CCT measurements obtained by Cirrus spectral domain optical coherence tomography (SD-OCT and ultrasonic pachymetry in healthy individuals. Materials and Methods: The study included 50 healthy consecutively selected individuals without ocular or systemic disease. CCT was first measured using OCT, and then using ultrasonic pachymetry. Results: Mean age of the participants was 31.44 years. Mean CCT measured using SD-OCT was 531.78 µm versus 535.15 µm by ultrasonic pachymetry. Mean CCT measurement obtained by Cirrus SD-OCT showed statistically significant difference by approximately 3.37 µm than the one obtained by ultrasonic pachymetry (t-test, p<0.05; however, Bland-Altman analysis proved that there was high concordance between the measurements. Conclusion: CCT measurements obtained by Cirrus SD-OCT were very similar to those obtained by ultrasonic pachymetry, and as such we think that Cirrus SD-OCT can be used in our present ophthalmology practice to measure OCT. (Turk J Ophthalmol 2014; 44: 259-62

  20. Acute Changes in Central Corneal Thickness According to Experimental Adjustment of Intraocular Pressure in Normal Canine Eyes

    OpenAIRE

    Park, Young-Woo; JEONG, Man-Bok; Lee, Eui Ri; Lee, Yesran; Ahn, Jae-Sang; Kim, Soo-Hyun; SEO, Kangmoon

    2013-01-01

    ABSTRACT Central corneal thickness (CCT) can be a promising source of glaucoma monitoring and diagnosis. This study evaluated changes in CCT according to experimental adjustment of intraocular pressure (IOP) in canine eyes. To adjust and measure IOP, each eye was cannulated with two 26-gauge needles under inhalant anesthesia. One needle was connected to a pressure transducer, and the other was connected to an adjustable bag of physiologic saline. IOP was stepwise increased from 10 mmHg to 70 ...

  1. Central corneal thickness and anterior chamber depth measurement by Sirius® Scheimpflug tomography and ultrasound

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    Jorge J

    2013-02-01

    Full Text Available J Jorge,1 JL Rosado,2 JA Díaz-Rey,1 JM González-Méijome11Clinical and Experimental Optometry Research Laboratory, Center of Physics (Optometry, School of Sciences, University of Minho, Braga, 2Opticlinic, Lisboa, PortugalBackground: The purpose of this study was to compare the accuracy of the new Sirius® Scheimpflug anterior segment examination device for measurement of central corneal thickness (CCT and anterior chamber depth (ACD with that of CCT measurements obtained by ultrasound pachymetry and ACD measurements obtained by ultrasound biometry, respectively.Methods: CCT and ACD was measured in 50 right eyes from 50 healthy subjects using a Sirius Scheimpflug camera, SP100 ultrasound pachymetry, and US800 ultrasound biometry.Results: CCT measured with the Sirius was 546 ± 39 µm and 541 ± 35 µm with SP100 ultrasound pachymetry (P = 0.003. The difference was statistically significant (mean difference 4.68 ± 10.5 µm; limits of agreement −15.8 to 25.20 µm. ACD measured with the Sirius was 2.96 ± 0.3 mm compared with 3.36 ± 0.29 mm using US800 ultrasound biometry (P < 0.001. The difference was statistically significant (mean difference −0.40 ± 0.16 mm; limits of agreement −0.72 to 0.07 mm. When the ACD values obtained using ultrasound biometry were corrected according to the values for CCT measured by ultrasound, the agreement increased significantly between both technologies for ACD measurements (mean difference 0.15 ± 0.16 mm; limits of agreement −0.16 to 0.45 mm.Conclusion: CCT and ACD measured by Sirius and ultrasound methods showing good agreement between repeated measurements obtained in the same subjects (repeatability with either instrument. However, CCT and ACD values, even after correcting ultrasound ACD by subtracting the CCT value obtained with either technology should not be used interchangeably.Keywords: Scheimpflug corneal tomography, ultrasound biometry, ultrasound pachymetry, limits of agreement

  2. Age-related changes in central corneal thickness in normal eyes among the adult Lithuanian population

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    Galgauskas S

    2014-07-01

    Full Text Available Saulius Galgauskas,1 Grazina Juodkaite,1 Janina Tutkuviene2 1Center of Eye Diseases, 2Faculty of Medicine, Department of Anatomy, Histology and Anthropology, Vilnius University, Vilnius, Lithuania Background: The purpose of this study was to estimate mean central corneal thickness (CCT and determine whether there are any correlations between CCT, age, and sex in the adult ­Lithuanian population.Methods: A total of 1,650 Caucasians of Lithuanian origin (aged 18–89 years comprising 688 (41.7% men and 962 (58.3% women were examined. Subjects were stratified by age into seven groups. CCT was measured using ultrasonic pachymetry. Correlations between CCT, age, and sex were sought.Results: Mean (± standard deviation CCT for both eyes was 544.6±30.5 µm. Mean CCT was 545.2±30.5 µm in the left eye and 544.6±30.5 µm in the right eye, and was 545.0±25.6 µm in men and 544.4±33.5 µm in women. Mean CCT was 550.8±35.7 µm in subjects aged 18–29 years, 557.5±27.6 µm in those aged 30–39 years, 551.3±31.4 µm in those aged 50–59 years, 544.0±31.4 µm in those aged 50–59 years, 544.2±31.6 µm in those aged 60–79 years, 535.1±27.8 µm in those aged 70–79 years, and 530.1±16.8 µm in those aged 80–89 years. No statistically significant difference in CCT was found between the sexes (P>0.05. However, there was a significant difference in subjects aged 18–29 years; men had higher CCT than women (P<0.05. A statistically significant negative correlation was found between CCT and age (r=−0.263, P<0.05 that was stronger in men (r=−0.406, P<0.05 than in women (r=−0.118, P<0.05. Conclusion: The mean CCT in adult Lithuanians was 544.6±30.5 µm, of the left eye 545.2±30.5 µm and of the right – 544.6±30.5 µm. CCT of the right eye was equal to the CCT of both eyes. Mean CCT was 545.0±25.6 µm in men and 544.4±33.5 µm in women. Young men tended to have higher CCT than women. CCT decreases over the

  3. Central corneal thickness and anterior chamber depth measurement by Sirius® Scheimpflug tomography and ultrasound

    Science.gov (United States)

    Jorge, J; Rosado, JL; Díaz-Rey, JA; González-Méijome, JM

    2013-01-01

    Background The purpose of this study was to compare the accuracy of the new Sirius® Scheimpflug anterior segment examination device for measurement of central corneal thickness (CCT) and anterior chamber depth (ACD) with that of CCT measurements obtained by ultrasound pachymetry and ACD measurements obtained by ultrasound biometry, respectively. Methods CCT and ACD was measured in 50 right eyes from 50 healthy subjects using a Sirius Scheimpflug camera, SP100 ultrasound pachymetry, and US800 ultrasound biometry. Results CCT measured with the Sirius was 546 ± 39 μm and 541 ± 35 μm with SP100 ultrasound pachymetry (P = 0.003). The difference was statistically significant (mean difference 4.68 ± 10.5 μm; limits of agreement −15.8 to 25.20 μm). ACD measured with the Sirius was 2.96 ± 0.3 mm compared with 3.36 ± 0.29 mm using US800 ultrasound biometry (P < 0.001). The difference was statistically significant (mean difference −0.40 ± 0.16 mm; limits of agreement −0.72 to 0.07 mm). When the ACD values obtained using ultrasound biometry were corrected according to the values for CCT measured by ultrasound, the agreement increased significantly between both technologies for ACD measurements (mean difference 0.15 ± 0.16 mm; limits of agreement −0.16 to 0.45 mm). Conclusion CCT and ACD measured by Sirius and ultrasound methods showing good agreement between repeated measurements obtained in the same subjects (repeatability) with either instrument. However, CCT and ACD values, even after correcting ultrasound ACD by subtracting the CCT value obtained with either technology should not be used interchangeably. PMID:23467857

  4. Comparison of central corneal thickness measured by Lenstar LS900, OrbscanⅡ and ultrasonic pachmetry

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    Hong-Tao Zhang

    2013-09-01

    Full Text Available AIM: To investigate the difference of central corneal thickness(CCTmeasured by Lenstar LS900, OrbscahⅡ system and ultrasonic pachmetry, and to evaluate the correlation and consistency of the results for providing a theoretical basis for clinical application.METHODS: The mean value of CCT in 70 eyes of 35 patients measured three times by Lenstar LS900, OrbscahⅡ system and ultrasonic pachmetry underwent statistical analysis. The difference of CCT was compared, and the correlation and consistency of three measurements were analyzed to provide theoretical basis for clinical application. CCT values measured by different methods were analyzed with randomized block variance analysis. LSD-t test was used for pairwise comparison between groups. The correlation of three measurement methods were analyzed by linear correlation analysis, and Bland-Altman was used to analyze the consistency.RESULTS: The mean CCT values measured by Lenstar LS900, OrbscanⅡ and ultrasonic pachmetry were 542.75±40.06, 528.74±39.59, 538.54±40.93μm, respectively. The mean difference of CCT measurement was 4.21±8.78μm between Lenstar LS900 and ultrasonic pachmetry, 14.01±13.39μm between Lenstar LS900 and Orbscan Ⅱ, 9.8±10.57μm between ultrasonic pachmetry and Orbscan Ⅱ. The difference was statistically significant(PP>0.05: There was positive correlation between CCT with Lenstar LS900 and ultrasonic pachmetry(r=0.977, 0.944; PCONCLUSION: There are excellent correlation among Lenstar LS900, Orbscan Ⅱ and ultrasonic pachmetry. Lenstar LS900 can be used as CCT non-contact measurement tool.

  5. Ocular biometry and central corneal thickness in children: a hospital-based study

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    Adem Gul

    2014-06-01

    Full Text Available Objetivo: Investigar a distribuição do comprimento axial, profundidade da câmara anterior, espessura do cristalino, profundidade da câmara vítrea e espessura corneal central em crianças em diferentes faixas etárias. Métodos: Foram estudados 364 olhos de 182 crianças entre 1 e 12 anos de idade. O comprimento axial, a profundidade da câmara anterior , a espessura do cristalino e a profundidade da câmara vítrea foram medidos por biometria ultrassônica. A espessura corneal central foi medida por paquimetria ultrassônica em todas as crianças. Resultados: A idade média foi de 6,54 ± 3,42 anos. O comprimento axial foi 20,95 mm no grupo de 1-2 anos de idade e 22,95 mm no grupo de 11-12 anos de idade. A espessura corneal central foi 556 µm no grupo de 1-2 anos de idade e 555 µm no grupo de 11-12 anos de idade. A profundidade da câmara anterior média e profundidade da câmara vítrea aumentou com a idade (3,06 mm a 3,44 mm de profundidade da câmara anterior, 13,75 mm a 15,99 mm de profundidade da câmara vítrea e da espessura do cristalino diminuiu com o aumento da idade (3,67 mm a 3,51 mm. Conclusões: Em nosso estudo, os valores do comprimento axial aumentou com a idade e atingiu os níveis adultos aos 9-10 anos de idade. A espessura do cristalino diminuiu gradualmente até os 12 anos de idade. As medições de espessura corneal central não seguiu um algoritmo linear.

  6. Comparison of Measurement of Central Corneal Thickness with Spectral Domain Optical Coherence Tomography and Standard Ultrasonic Pachymeter in Premature Infants

    OpenAIRE

    Emre Hekimoglu; Muhammet Kazım Erol; Devrim Toslak; Deniz Turgut Coban; Berna Doğan; Ozgur Yucel

    2015-01-01

    Purpose. To evaluate the repeatability of measurement of central corneal thickness (CCT) by spectral domain optical coherence (SD-OCT) in premature infants and compare it to CCT measurement by ultrasonic pachymetry (USP). Methods. Three CCT measurements of the left eyes of 50 premature infants were obtained by SD-OCT using the iVue system. 10 CCT measurements of each 28 left eyes of 28 infants were obtained by USP using the Pacscan 300P system. Bland-Altman plots were developed and the limit ...

  7. Distribution of Central Corneal Thickness and its Association with Ocular Parameters in a Large Central European Cohort: The Gutenberg Health Study

    OpenAIRE

    Hoffmann, Esther M; Lamparter, Julia; Mirshahi, Alireza; Elflein, Heike; Hoehn, René; Wolfram, Christian; Lorenz, Katrin; Adler, Max; Wild, Philipp S.; Schulz, Andreas; Mathes, Barbara; Blettner, Maria; Pfeiffer, Norbert

    2013-01-01

    Main objective To evaluate the distribution of central corneal thickness (CCT) in a large German cohort and to analyse its relationship with intraocular pressure and further ocular factors. Design Population-based, prospective, cohort study. Methods The Gutenberg Health Study (GHS) cohort included 4,698 eligible enrollees of 5,000 subjects (age range 35–74 years) who participated in the survey from 2007 to 2008. All participants underwent an ophthalmological examination including slitlamp bio...

  8. Central Corneal Thickness in Highly Myopic Eyes: Inter-device Agreement of Ultrasonic Pachymetry, Pentacam and Orbscan II Before and After Photorefractive Keratectomy

    OpenAIRE

    Nader Nassiri; Kourosh Sheibani; Sare Safi; Saman Nassiri; Alireza Ziaei; Farnaz Haji; Shiva Mehravaran; Nariman Nassiri

    2014-01-01

    Purpose: To determine inter-device agreement for central corneal thickness (CCT) measurement among ultrasound pachymetry, rotating Scheimpflug imaging (Pentacam, Oculus, Wetzlar, Germany), and scanning slit corneal topography (Orbscan II, Bausch & Lomb, Rochester, NY, USA) in highly myopic eyes before and after photorefractive keratectomy (PRK). Methods: This prospective comparative study included 61 eyes of 32 patients with high myopia who underwent PRK. Six month postoperative CCT value...

  9. Measurement of central corneal thickness by ultrasonic pachymeter and oculus pentacam in patients with well-controlled glaucoma: hospital-based comparative study

    OpenAIRE

    Rashid RF; Farhood QK

    2016-01-01

    Riyam Faihan Rashid, Qasim K Farhood Department of Ophthalmology, College of Medicine, University of Babylon, Babylon, Iraq Background: The measurement of central corneal thickness (CCT) plays an important role in the diagnosis and treatment of glaucoma and many corneal diseases.Objective of the study: To compare the measurement of CCT by ultrasonic pachymeter with that measured by oculus pentacam in both normal subjects and patients with well-controlled glaucoma.Patients and methods: In 17...

  10. Diurnal variations in human corneal thickness.

    OpenAIRE

    Harper, C L; Boulton, M. E.; Bennett, D.; Marcyniuk, B; Jarvis-Evans, J H; Tullo, A. B.; Ridgway, A E

    1996-01-01

    AIM: To elucidate the diurnal variation in human corneal thickness over a 48 hour period. METHOD: Changes in central corneal thickness were monitored in eight healthy subjects (four male, four female) aged between 10 and 63 years using an ultrasonic pachymeter. Measurements were made over a 48 hour period-immediately before sleep, immediately upon waking and at 15, 30, 45 minutes, 1, 1.5, 2, 2.5, 3 hours, and at 2 hour intervals thereafter throughout the remainder of each day. RESULTS: The me...

  11. Long-term evaluation of eyes with central corneal thickness <400 µm following laser in situ keratomileusis

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    Djodeyre MR

    2016-03-01

    Full Text Available Mohammad Reza Djodeyre,1 Jaime Beltran,2 Julio Ortega-Usobiaga,3 Felix Gonzalez-Lopez,4 Ana Isabel Ruiz-Rizaldos,1 Julio Baviera2 1Department of Refractive Surgery, Clinica Baviera, Zaragoza, 2Department of Refractive Surgery, Clinica Baviera, Valencia, 3Department of Research and Development, Clinica Baviera, Bilbao, 4Department of Refractive Surgery, Clinica Baviera, Madrid, Spain Purpose: To study long-term refractive and visual outcomes of laser in situ keratomileusis (LASIK in eyes with a postoperative thin central cornea.  Methods: In this retrospective observational case series, we studied 282 myopic eyes with a normal preoperative topographic pattern and postoperative thin corneas (<400 µm that had at least 3 years of follow-up after LASIK in three private clinics. The main outcome measures were safety, efficacy, predictability, percent tissue altered, and complications.  Results: The mean postoperative central corneal thickness was 392.05 µm (range: 363.00–399.00 µm. After a mean follow-up of 6.89±2.35 years (standard deviation, the safety index was 1.17, the efficacy index was 0.94, and predictability (±1.00 diopter [D] was 73.49. The mean residual stromal bed thickness was 317.34±13.75 µm (range: 275–356 µm, the mean flap thickness was 74.76±13.57 µm (range: 55–124 µm, and the mean percent tissue altered was 37.12%±3.62% (range: 27.25%–49.26%. No major complications were recorded.  Conclusion: LASIK with a resultant central cornea thickness <400 µm seems to be effective, safe, and predictable provided that preoperative topography is normal and the residual stromal bed thickness is >275 µm. Keywords: LASIK, thin, cornea, ectasia, myopia, pachymetry, topography

  12. Corneal thickness and I.O.P. changes in rhegmatogenous retinal detachment

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    Azad Raj

    1990-01-01

    Full Text Available Twenty patients with Rhegmatogenous retinal detachment were subjected to applanation tonometry and Corneal Thickness measurement to ascertain (i the change in central & peripheral corneal thickness and (ii effect of Intra Ocular Pressure on these corneal changes. Twenty age and sex matched controls also underwent similar investigation. It was observed that both the mean Intra Ocular Pressure and the corneal thickness (both Peripheral Corneal Thickness and Central Corneal Thickness] of the affected eye showed statistically significant reduction (P 0.001 when compared to Intra Ocular Pressure and Corneal Thickness changes of fellow-eyes and eyes of control subjects. In addition to these even the fellow eyes which had normal Intra Ocular Pressure, showed statistically low Central Corneal Thickness measurement, when compared with controls. In view of the above observation and reduction in Corneal Thickness measurement, the present study indicates generalised corneal changes in Rhegmatogenous retinal detachment unrelated to intraocular pressure.

  13. Ethnic Variations in Central Corneal Thickness in a Rural Population in China: The Yunnan Minority Eye Studies.

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    Chen-Wei Pan

    Full Text Available To describe the ethnic differences in central corneal thickness (CCT in population-based samples of ethnic Bai, Yi and Han people living in rural China.6504 adults (2119 ethnic Bai, 2202 ethnic Yi and 2183 ethnic Han aged 50 years or older participated in the study. Each subject underwent standardized ocular examinations and interviewer-administered questionnaires for risk factor assessment. CCT was measured for both eyes using an ultrasound pachymeter. Regression and principal component analysis were performed to examine the relationship of ethnicity and other factors with CCT.The mean CCT readings were 536.4 ± 34.2 μm in ethnic Bai, 532.1 ± 32.1 μm in ethnic Yi and 529.6 ± 32.7 μm in ethnic Han adults (P<0.001, respectively. There was a decreasing trend of mean CCT with increasing age across all ethnic groups. In multivariate linear regression models, increasing CCT was associated with younger age (P<0.001, male gender (P<0.001, Bai (P<0.001 or Yi (P<0.001 ethnicity, greater body mass index (P<0.001, higher systolic blood pressure (P<0.001, greater corneal curvature (P<0.001, deeper anterior chamber (P < 0.001, and thicker lens (P<0.001. Ethnicity contributed significantly to presence of thin cornea (60%; P< 0.001 compared with other factors. CCT had similar impact on intraocular pressure readings across all ethnic groups.This study of more than 6500 multiethnic participants demonstrates significant ethnic variations in CCT, with Han ethnicity having the thinnest cornea compared with ethnic minorities. These data are essential to guide future multiethnic clinical trials on CCT-related ocular conditions such as glaucoma.

  14. Comparing acromegalic patients to healthy controls with respect to intraocular pressure, central corneal thickness, and optic disc topography findings

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    Emine Sen

    2014-01-01

    Full Text Available Aims: The aim was to compare the intraocular pressure (IOP, central corneal thickness (CCT, and optic disc topography findings of biochemically controlled acromegalic patients and the control group and to evaluate the effect of the duration of acromegaly and serum growth hormone and insulin-like growth factor-1 (IGF-1 levels on these ocular parameters. Materials and Methods: IOP measurement with Goldmann applanation tonometry, CCT measurement with ultrasonic pachymetry, and topographic analysis with Heidelberg retinal tomograph III were performed on 35 biochemically controlled acromegalic patients and 36 age- and gender-matched controls. Results: Mean IOP and CCT were 14.7 ± 2.9 mmHg and 559.5 ± 44.9 μm in the acromegaly patients and 13.0 ± 1.6 mmHg and 547.1 ± 26.7 μm in controls (P = 0.006 and P = 0.15, respectively. A significant moderate correlation was found between the duration of acromegaly and CCT (r = 0.391 and IOP (r = 0.367. Mean retinal nerve fiber layer (RNFL thickness was significantly lower in the acromegalic patients (0.25 ± 0.05 mm as compared to controls (0.31 ± 0.09 mm (P = 0.01. A significant moderate correlation was detected between IGF-1 level and disc area (r = 0.362, cup area (r = 0.389 and cup volume (r = 0.491. Conclusion: Biochemically controlled acromegalic patients showed significantly higher CCT and IOP levels and lower RNFL thickness compared to healthy controls and the duration of disease was correlated with CCT and IOP levels.

  15. Decreased keratocyte density and central corneal thickness in primary open-angle glaucoma patients undergoing treatment with topical prostaglandin analogues

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    Sibel Kocabeyoglu

    2015-01-01

    Full Text Available Purpose: To evaluate whether prostaglandin (PG analogue use is associated with alterations in keratocyte density and central corneal thickness (CCT in subjects with primary open-angle glaucoma (POAG. Materials and Methods: Thirty-five POAG patients treated with PG analogues for >2 years and 35 control subjects without glaucoma were included in this cross-sectional study. All subjects were underwent CCT measurements using ultrasound pachymetry. Keratocyte densities of each stromal layer were determined by in vivo confocal microscopy. Student′s t-test and Chi-square test were used for statistical evaluations. Correlations between keratocyte densities and CCT were analyzed using Pearson′s correlation analysis. Results: Keratocyte densities in each stromal layer were significantly lower in glaucoma patients receiving PG analogues as compared to those of controls (P < 0.001. The mean CCT was also lower in glaucoma patients (515.2 ± 18.8 μ than control subjects (549.6 ± 21.1 μ, P < 0.001. A positive correlation between keratocyte densities in each stromal layer and CCT was observed in POAG patients. Conclusions: Long-term administration of topical PG analogues may adversely influence keratocyte densities and CCT. Further prospective studies are required clarify the relationship between PG analogues and their effects on the cornea.

  16. Comparison of Measurement of Central Corneal Thickness with Spectral Domain Optical Coherence Tomography and Standard Ultrasonic Pachymeter in Premature Infants

    Directory of Open Access Journals (Sweden)

    Emre Hekimoglu

    2015-01-01

    Full Text Available Purpose. To evaluate the repeatability of measurement of central corneal thickness (CCT by spectral domain optical coherence (SD-OCT in premature infants and compare it to CCT measurement by ultrasonic pachymetry (USP. Methods. Three CCT measurements of the left eyes of 50 premature infants were obtained by SD-OCT using the iVue system. 10 CCT measurements of each 28 left eyes of 28 infants were obtained by USP using the Pacscan 300P system. Bland-Altman plots were developed and the limit of agreement (LoA was determined to compare the mean of the SD-OCT and USP measurements. Results. No statistically significant difference was found among the 3 CCT measurements by SD-OCT. Both USP and SD-OCT have been performed for only left eyes of 28 of the 50 babies. Those results have been compared with each other. A statistically significant difference was found between the mean CCT measurements by SD-OCT and USP (p<0.05. The LoA between the SD-OCT and USP measurements ranged from 11.4 to −64.1. Conclusions. CCT can be measured using the iVue SD-OCT system with a high level of repeatability. Although measurement of CCT by SD-OCT and USP is highly correlated, the 2 systems cannot be used interchangeably in premature infants.

  17. The Path to Open-Angle Glaucoma Gene Discovery: Endophenotypic Status of Intraocular Pressure, Cup-to-Disc Ratio, and Central Corneal Thickness

    OpenAIRE

    Charlesworth, Jac; Kramer, Patricia L.; Dyer, Tom; Diego, Victor; Samples, John R.; Craig, Jamie E; Mackey, David A.; Hewitt, Alex W; Blangero, John; Wirtz, Mary K.

    2010-01-01

    The primary open-angle glaucoma (POAG) risk factors intraocular pressure, vertical cup-to-disc ratio, and central corneal thickness are shown to be highly heritable in 22 large POAG families from Australia and the Northwest Pacific region of the United States. Furthermore, bivariate genetic analysis reveals that both intraocular pressure and vertical cup-to-disc ratio represent potentially useful endophenotypes for the genetic dissection of POAG risk.

  18. Comparison of Central Corneal Thickness Measurements by Ultrasonic Pachymetry, Orbscan II, and SP3000P in Eyes with Glaucoma or Glaucoma Suspect

    OpenAIRE

    Mei-Ching Teng; Ing-Chou Lai; Tsung-Ho Ou

    2012-01-01

    Background: Intraocular pressure (IOP) measurements are affected by the central cornea thickness (CCT). The conventional method for CCT measurement is ultrasonic pachymetry. However, noncontact procedures lower the risk of infection and corneal damage. In this study, we compared the CCT measured by Orbscan II, SP3000P, and ultrasonic pachymetry in patients with glaucoma or glaucoma suspect.Methods: The CCT of 208 eyes (46 eyes with glaucoma suspect, 42 with primary angle-closure glaucoma, and...

  19. Distribution of central corneal thickness and its association with ocular parameters in a large central European cohort: the Gutenberg health study.

    Directory of Open Access Journals (Sweden)

    Esther M Hoffmann

    Full Text Available MAIN OBJECTIVE: To evaluate the distribution of central corneal thickness (CCT in a large German cohort and to analyse its relationship with intraocular pressure and further ocular factors. DESIGN: Population-based, prospective, cohort study. METHODS: The Gutenberg Health Study (GHS cohort included 4,698 eligible enrollees of 5,000 subjects (age range 35-74 years who participated in the survey from 2007 to 2008. All participants underwent an ophthalmological examination including slitlamp biomicroscopy, intraocular pressure measurement, central corneal thickness measurement, fundus examination, and were given a questionnaire regarding glaucoma history. Furthermore, all subjects underwent fundus photography and visual field testing using frequency doubling perimetry. RESULTS: Mean CCT was 557.3 ± 34.3 µm (male and 551.6±35.2 µm in female subjects (Mean CCT from right and left eyes. Younger male participants (35-44 years presented slightly thicker CCT than those older. We noted a significant CCT difference of 4 µm between right and left eyes, but a high correlation between eyes (Wilcoxon test for related samples: p<0.0001. Univariable linear regression stratified by gender showed that IOP was correlated with CCT (p<0.0001. A 10 µm increase in CCT led to an increase in IOP between 0.35-0.38 mm Hg, depending on the eye and gender. Multivariable linear regression analysis revealed correlations between gender, spherical equivalent (right eyes, and CCT (p<.0001 and p=0.03, respectively. CONCLUSIONS: We observed positive correlations between CCT and IOP and gender. CCT was not correlated with age, contact lens wear, positive family history for glaucoma, lens status, or iris colour.

  20. The Effect of Nd: YAG Laser Capsulotomy on Visual Acuity, Intraocular Pressure, Central Corneal Thickness, and Refractive Status

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    Nihat Polat

    2014-08-01

    Full Text Available Objectives: To evaluate the changes in best-corrected visual acuity (BCVA, intraocular pressure (IOP, central corneal thickness (CCT, and spherical equivalent (SE before and after Nd: YAG laser capsulotomy. Materials and Methods: This study included 68 patients (40 men, 28 women who had posterior capsule opacification. The subjects underwent Nd: YAG laser capsulotomy with a minimal energy and shooting number. BCVA, IOP, CCT, and SE were measured before and 1 week, 1 and 3 months after laser capsulotomy. The post-treatment measurements were compared with the pre-treatment ones statistically. Results: There were statistically significant differences between pre- and post-laser BCVA values at 1 week, 1 month, and 3 months (p0.05. There were statistically significant differences between pre- and post-laser SE values at 1 week, 1 month, and 3 months (p<0.001. The SE value at 1 week was not statistically significantly different from those at 1 and 3 months (p=0.068 and p=0.541, respectively. There were statistically significant differences between pre- and post-laser CCT values at 1 week, 1 month, and 3 months (p<0.001, however, no statistically significant differences were found between the CCT measurement at 1 week and those at 1 and 3 months (p=0.296 and p=0.304, respectively. There were statistically significant differences between pre- and post-laser IOP values at 1 week, 1 month, and 3 months (p<0.001, while there were no statistically significant differences between IOP measurements at 1 week and those at 1 and 3 months (p=0.438 and p=0.664, respectively. Conclusion: Substantial changes were observed, especially at first postoperative week, for BCVA, IOP, CCT, and SE in patients with posterior capsule opacification who underwent Nd: YAG laser capsulotomy. (Turk J Ophthalmol 2014; 44: 275-9

  1. Comparison of central corneal thickness measured with Orbscan-Ⅱ, Pentacam and ultrasonic pachymetry%Orbscan-Ⅱ、Pentacam及超声测厚仪角膜厚度测量值的比较

    Institute of Scientific and Technical Information of China (English)

    王霁雪; 吴荒; 杨隆艳; 郑雅娟

    2010-01-01

    Objective To assess the reliability of Orbscan-Ⅱ , Pentacam and ultrasonic pachymetry (US) for central corneal thickness (CCT) measurements. Methods Central corneal thick- ness was measured using Orbscan-Ⅱ, Pentacam and ultrasonic pachymetry in 159 preoperative cases (318 eyes). Patients were further divided into three groups according to corneal thickness (0.05).结论 三种方法用于测量准分子激光角膜手术前近视患者的角膜中央厚度时虽然存在一定差异,但总体上无统计学意义,具有很好的协同性,但相互间还不能完全替代.

  2. Repeatability and Reproducibility of Measurements Using a NT-530P Noncontact Tono/Pachymeter and Correlation of Central Corneal Thickness with Intraocular Pressure

    Science.gov (United States)

    Kamiya, Kazutaka; Fujiwara, Kazuko; Shimizu, Kimiya

    2013-01-01

    Purpose. To investigate the repeatability and reproducibility of intraocular pressure (IOP) and central corneal thickness (CCT) measurements using a noncontact tono/pachymeter (NT-530P) and to assess the correlation of CCT with IOP. Methods. Forty-six eyes of healthy volunteers were measured by two examiners. Three consecutive measurements per eye were performed. Repeatability was assessed using the coefficient of variation, and reproducibility was assessed using Bland-Altman plots. Linear correlations were used to determine agreement between CCT and noncorrected IOP and CCT and corrected IOP, which was calculated using a formula built into the NT-530P. Results. The coefficient of variation for IOP was 6.4% and for CCT was 0.4%. The 95% limits of agreement between examiners were −0.17 ± 1.42 mmHg (range: −2.95 to 2.61 mmHg) for IOP, −0.93 ± 4.37 μm (range: −9.50 to 7.64 μm) for CCT. The corrected IOP was significantly higher than the noncorrected IOP (P = 0.010.3). The noncorrected IOP significantly correlated with CCT (r = −0.4883, P = 0.0006). The corrected IOP showed no significant correlation with CCT (r = −0.0285, P = 0.8509). Conclusions. NT-530P offered repeatability and reproducibility in both IOP and CCT measurements. The corrected IOP calculated using the NT-530P was independent of the CCT, suggesting that this IOP may be less influenced by the central corneal thickness. PMID:24222904

  3. Repeatability and Reproducibility of Measurements Using a NT-530P Noncontact Tono/Pachymeter and Correlation of Central Corneal Thickness with Intraocular Pressure

    Directory of Open Access Journals (Sweden)

    Fusako Fujimura

    2013-01-01

    Full Text Available Purpose. To investigate the repeatability and reproducibility of intraocular pressure (IOP and central corneal thickness (CCT measurements using a noncontact tono/pachymeter (NT-530P and to assess the correlation of CCT with IOP. Methods. Forty-six eyes of healthy volunteers were measured by two examiners. Three consecutive measurements per eye were performed. Repeatability was assessed using the coefficient of variation, and reproducibility was assessed using Bland-Altman plots. Linear correlations were used to determine agreement between CCT and noncorrected IOP and CCT and corrected IOP, which was calculated using a formula built into the NT-530P. Results. The coefficient of variation for IOP was 6.4% and for CCT was 0.4%. The 95% limits of agreement between examiners were −0.17±1.42 mmHg (range: −2.95 to 2.61 mmHg for IOP, −0.93±4.37 μm (range: −9.50 to 7.64 μm for CCT. The corrected IOP was significantly higher than the noncorrected IOP (P=0.010.3. The noncorrected IOP significantly correlated with CCT (r=−0.4883, P=0.0006. The corrected IOP showed no significant correlation with CCT (r=−0.0285, P=0.8509. Conclusions. NT-530P offered repeatability and reproducibility in both IOP and CCT measurements. The corrected IOP calculated using the NT-530P was independent of the CCT, suggesting that this IOP may be less influenced by the central corneal thickness.

  4. Comparison of Central Corneal Thickness Measurements by Ultrasonic Pachymetry, Orbscan II, and SP3000P in Eyes with Glaucoma or Glaucoma Suspect

    Directory of Open Access Journals (Sweden)

    Mei-Ching Teng

    2012-06-01

    Full Text Available Background: Intraocular pressure (IOP measurements are affected by the central cornea thickness (CCT. The conventional method for CCT measurement is ultrasonic pachymetry. However, noncontact procedures lower the risk of infection and corneal damage. In this study, we compared the CCT measured by Orbscan II, SP3000P, and ultrasonic pachymetry in patients with glaucoma or glaucoma suspect.Methods: The CCT of 208 eyes (46 eyes with glaucoma suspect, 42 with primary angle-closure glaucoma, and 120 with primary open-angle glaucoma was measured using Orbscan II, SP3000P, and ultrasonic pachymetry. We compared the linear correlation of the CCT between each mode.Results: The mean CCT measured by Orbscan II (563.63 Ų 35.867 µm was larger than with the other two devices. There were significant linear correlations between measurements with ultrasonic pachymetry and Orbscan II (Pearson correlation coefficient (r = 0.793, p 500 µm to ≤ 578 µm, and > 578 µm. There was no significant linear correlation between ultrasonic pachymetry and Orbscan II in the thin group. But, in the intermediate and thick CCT groups, there were significant linear correlations between each of the three devices.Conclusion: We showed good linear correlations of CCT measurements between each of 3 devices, especially in the intermediate and thickest CCTs. These results will be helpful in predicting the relationship between IOP and CCT for the diagnosis and screening of glaucoma; even we used optic systems.

  5. Short-term variation of central corneal thickness and axial anterior chamber depth of healthy eyes using Scheimpflug photography via the Oculus Pentacam*

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    S. D. Mathebula

    2009-12-01

    Full Text Available The purpose of this study was to investigate short-term variation and intra-subject repeatabil-ity of  human central corneal thickness (CCT and axial anterior chamber depth (AACD measure-ments obtained using the Oculus Pentacam. Forty consecutive images of the right eye of the anteriorsegment of 10 young and healthy individuals were measured with the Pentacam. Measurements of CCT and AACD were ob-tained from these images and means, standard deviations,variances and repeatability of the measurements were investigated. Both parameters (CCTand AACD showed small variation with good orexcellent repeatability for all eyes. The inter-subject or overall means and standard deviations for CCT and AACD of the 10 right eyes were 0.555 ±0.05 millimeters (or 555 ± 50 microns and 3.206± 0.04 millimeters, respectively. The individual or intra-subject averages for samples of CCT and AACD measurements are also provided in this paper. Univariate normality of the data was explored with Kolmogorov-Smirnov, Lilliefors and ShapiroWilks tests and we found that generally the data was normally distributed although there were some exceptions. Based on the results of this study, the Oculus Pentacam appears to provide repeatable and reliable measures for both CCT and AACD in young,normal eyes. Further research is, however, needed to determine short-term variation and repeatability of CCT and AACD with the Pentacam in more com-plicated eyes with, say, corneal scarring or ectasia or where refractive surgery may be an issue.

  6. Measurement of central corneal thickness by ultrasonic pachymeter and oculus pentacam in patients with well-controlled glaucoma: hospital-based comparative study

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    Rashid RF

    2016-03-01

    Full Text Available Riyam Faihan Rashid, Qasim K Farhood Department of Ophthalmology, College of Medicine, University of Babylon, Babylon, Iraq Background: The measurement of central corneal thickness (CCT plays an important role in the diagnosis and treatment of glaucoma and many corneal diseases.Objective of the study: To compare the measurement of CCT by ultrasonic pachymeter with that measured by oculus pentacam in both normal subjects and patients with well-controlled glaucoma.Patients and methods: In 173 eyes of both controls and patients with open-angle glaucoma (normal intraocular pressure attending Ibn Al Haitham Teaching Eye Hospital, CCT was measured by oculus pentacam and then by ultrasound pachymeter at the same morning by the same technicians.Results: The results showed no significant difference in CCT readings measured by the two devices in both glaucoma and control groups (glaucoma group: 547.29±49.32 µm with pentacam vs 547.66±45.24 µm with ultrasound pachymeter; control group: 551.02±36.28 µm with pentacam vs 541.25±34.96 µm with ultrasound pachymeter. P-values were >0.05 in both groups (statistically not significant.Conclusion and recommendation: Ultrasonic pachymeter and oculus pentacam can be used interchangeably in measuring CCT, and we recommend a nontouch method (in this study, pentacam Scheimpflug camera for measuring CCT during assessment of patients with glaucoma or any ocular disease or surgery. Keywords: CCT, open-angle glaucoma, ultrasound pachymeter, Scheimpflug camera

  7. Correlação entre a espessura corneana central e o comprimento axial ocular nos portadores de glaucoma e em olhos normais Correlation between central corneal thickness and axial length in patients with glaucoma and normal eyes

    Directory of Open Access Journals (Sweden)

    Paula Resende Aquino de Assis Pereira Mello

    2009-08-01

    Full Text Available OBJETIVO: Correlacionar a espessura corneana central com o comprimento axial ocular nos portadores de glaucoma primário de ângulo aberto, com glaucoma primário de fechamento angular e indivíduos com olhos normais. MÉTODOS: A amostra foi constituída de 94 olhos de 94 pacientes, divididos em três grupos compostos por 33 olhos de 33 pacientes portadores de glaucoma primário de ângulo aberto, 30 olhos de 30 pacientes com glaucoma primário de fechamento angular e 31 olhos normais de 31 indivíduos. A espessura corneana e o comprimento axial do olho foram obtidos pela paquimetria ultrassônica e ecobiometria, respectivamente. RESULTADOS: A média da espessura corneana central foi de 535,1 mm no glaucoma primário de fechamento angular; 520,6 mm no glaucoma primário de ângulo aberto e 519,2 mm nos olhos normais (p=0,18. A média do comprimento axial do globo ocular nos portadores de glaucoma primário de fechamento angular foi de 22,16 mm e nos grupos com glaucoma primário de ângulo aberto e olhos normais foram de 22,68 mm e 22,64 mm, respectivamente (p=0,13. Não houve correlação significativa entre a espessura corneana central e comprimento axial do globo ocular nos grupos com glaucoma primário de fechamento angular (r=-0,085; p=0,65, glaucoma primário de ângulo aberto (r=-0,070; p=0,69 e olhos normais (r=-0,120; p=0,52. CONCLUSÃO: Os resultados deste trabalho sugerem não haver correlação entre a espessura corneana central e o comprimento axial do globo ocular nos portadores de glaucoma e indivíduos com olhos normais.PURPOSE: To evaluate and to correlate the central corneal thickness with the ocular axial length in patients with primary open-angle glaucoma, primary angle-closure glaucoma and individuals with normal eyes. METHODS: The sample was composed of 94 patients' eyes, divided into three groups constituted of 33 eyes of 33 primary open-angle glaucoma patients, 30 eyes of 30 primary angle-closure glaucoma patients and 31

  8. Differences in Central Corneal Thickness between Spectral Domain-Optical Coherence Tomography and Ultrasound Pachymetry in Patients with Dry Eye Disease

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    Ali Riza Cenk Celebi

    2016-01-01

    Full Text Available Purpose. To compare central corneal thickness (CCT values via Spectral Domain-Optical Coherence Tomography (SD-OCT and ultrasonic pachymetry in patients with severe dry eye disease (DED to determine the level of agreement between these 2 methods. Methods. The paired samples t-test was used to compare CCT values in severe DED patients. Matching analysis between methods was performed using intraclass correlation coefficient (ICC. Intrasession reliability of the measurement methods was calculated via the concordance correlation coefficient (CCC, variation equivalent, and Pearson’s correlation coefficient. The Bland-Altman procedure was used to graphically represent the differences between CCT values. Results. The study included 56 eyes of 24 female and 4 male patients. Mean age of the patients was 50.9±11.3 years. Mean CCT via Cirrus SD-OCT was 523.82±30.98 μm versus 530.050±31.85 μm via ultrasonic pachymetry (paired samples t-test, P<0.001. The Bland-Altman plot showed good agreement between the examiners. The ICC for repeatability was 0.974. The CCC between the 2 methods’ CCT values was 0.973. The variation equivalent was 0.976 and Pearson’s correlation coefficient was 99.3%, which also indicated high correlation between the 2 methods’ measurements. Conclusions. The present findings show that in patients with severe DED Cirrus SD-OCT provides reliable intraobserver CCT values.

  9. Evaluation of corneal thickness and topography in normal eyes using the Orbscan corneal topography system

    OpenAIRE

    Liu, Z.; HUANG, A; Pflugfelder, S.

    1999-01-01

    AIMS—To map the thickness, elevation (anterior and posterior corneal surface), and axial curvature of the cornea in normal eyes with the Orbscan corneal topography system.
METHODS—94 eyes of 51 normal subjects were investigated using the Orbscan corneal topography system. The anterior and posterior corneal elevation maps were classified into regular ridge, irregular ridge, incomplete ridge, island, and unclassified patterns, and the axial power maps were grouped into round, oval, symmetric bo...

  10. Central corneal thickness, intraocular pressure, and degree of myopia in an adult myopic population aged 20 to 40 years in southeast Spain: determination and relationships

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    Manuel Garcia-Medina

    2011-02-01

    Full Text Available Manuel Garcia-Medina1, Jose Javier Garcia-Medina2,3, Pablo Garrido-Fernandez1, Jose Galvan-Espinosa1, Jesus Martin-Molina1, Carlos Garcia-Maturana4, Sergio Perez-Pardo1, Maria Dolores Pinazo-Duran3 1Department of Ophthalmology, Torrecardenas Hospital, Almeria, Spain; 2Department of Ophthalmology, Huercal Overa Hospital, Almeria, Spain; 3Ophthalmology Research Unit “Santiago Grisolia”, University Hospital Doctor Peset, Valencia, Spain; 4University of Sevilla, SpainObjective: To determine the values of, and study the relationships among, central corneal thickness (CCT, intraocular pressure (IOP, and degree of myopia (DM in an adult myopic population aged 20 to 40 years in Almeria (southeast Spain. To our knowledge this is first study of this kind in this region.Methods: An observational, descriptive, cross-sectional study was done in which a sample of 310 myopic patients (620 eyes aged 20 to 40 years was selected by gender- and age-stratified sampling, which was proportionally fixed to the size of the population strata for which a 20% prevalence of myopia, 5% epsilon, and a 95% confidence interval were hypothesized. We studied IOP, CCT, and DM and their relationships by calculating the mean, standard deviation, 95% confidence interval for the mean, median, Fisher’s asymmetry coefficient, range (maximum, minimum, and the Brown-Forsythe’s robust test for each variable (IOP, CCT, and DM.Results: In the adult myopic population of Almeria aged 20 to 40 years (mean of 29.8, the mean overall CCT was 550.12 µm. The corneas of men were thicker than those of women (P = 0.014. CCT was stable as no significant differences were seen in the 20- to 40-year-old subjects’ CCT values. The mean overall IOP was 13.60 mmHg. Men had a higher IOP than women (P = 0.002. Subjects over 30 years (13.83 had a higher IOP than those under 30 (13.38 (P = 0.04. The mean overall DM was -4.18 diopters. Men had less myopia than women (P < 0.001. Myopia was stable in the

  11. Comparison between a New Optical Biometry Device and an Anterior Segment Optical Coherence Tomographer for Measuring Central Corneal Thickness and Anterior Chamber Depth

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    Jinhai Huang

    2016-01-01

    Full Text Available Purpose. To compare between a new optical biometer (AL-Scan, Nidek Co., Aichi, Japan and an anterior segment optical coherence tomographer (Visante AS-OCT, Carl Zeiss Meditec, Dublin, USA for measuring central corneal thickness (CCT, anterior chamber depth (ACD, and aqueous depth (AD. Methods. Sixty-three eyes of 63 normal subjects were examined with AL-Scan and Visante AS-OCT in this prospective study. One eye per subject was measured three times with both devices to record their CCT, ACD, and AD. All procedures were performed by the same operator. Agreement between the two devices was assessed using paired t-tests, Bland-Altman plots, and 95% limits of agreement (LoA. Results. The mean CCT, ACD, and AD measured by AL-Scan were 538.59±27.37 μm, 3.70±0.30 mm, and 3.16±0.30 mm, respectively. The mean values obtained by the Visante OCT were 536.14±26.61 μm for CCT, 3.71±0.29 mm for ACD, and 3.17±0.29 mm for AD. The mean CCT by the AL-Scan was higher than that obtained by the Visante AS-OCT (difference = 2.45±6.07 μm, P<0.05. The differences in ACD and AD measurements were not statistically significant. The 95% LoA of CCT, ACD, and AD were between −9.44 and 14.35 μm, −0.15 and 0.12 mm, and −0.15 and 0.12 mm, respectively. Conclusions. Since these two devices were comparable for measuring CCT, ACD, and AD, their results can be interchangeably used in the clinic.

  12. Comparison between a New Optical Biometry Device and an Anterior Segment Optical Coherence Tomographer for Measuring Central Corneal Thickness and Anterior Chamber Depth.

    Science.gov (United States)

    Huang, Jinhai; Lu, Weicong; Savini, Giacomo; Chen, Hao; Wang, Chengfang; Yu, Xinxin; Bao, Fangjun; Wang, Qinmei

    2016-01-01

    Purpose. To compare between a new optical biometer (AL-Scan, Nidek Co., Aichi, Japan) and an anterior segment optical coherence tomographer (Visante AS-OCT, Carl Zeiss Meditec, Dublin, USA) for measuring central corneal thickness (CCT), anterior chamber depth (ACD), and aqueous depth (AD). Methods. Sixty-three eyes of 63 normal subjects were examined with AL-Scan and Visante AS-OCT in this prospective study. One eye per subject was measured three times with both devices to record their CCT, ACD, and AD. All procedures were performed by the same operator. Agreement between the two devices was assessed using paired t-tests, Bland-Altman plots, and 95% limits of agreement (LoA). Results. The mean CCT, ACD, and AD measured by AL-Scan were 538.59 ± 27.37 μm, 3.70 ± 0.30 mm, and 3.16 ± 0.30 mm, respectively. The mean values obtained by the Visante OCT were 536.14 ± 26.61 μm for CCT, 3.71 ± 0.29 mm for ACD, and 3.17 ± 0.29 mm for AD. The mean CCT by the AL-Scan was higher than that obtained by the Visante AS-OCT (difference = 2.45 ± 6.07 μm, P LoA of CCT, ACD, and AD were between -9.44 and 14.35 μm, -0.15 and 0.12 mm, and -0.15 and 0.12 mm, respectively. Conclusions. Since these two devices were comparable for measuring CCT, ACD, and AD, their results can be interchangeably used in the clinic. PMID:27403339

  13. Effect of compound tropicamide eye drop on measurement of central corneal thickness%复方托吡卡胺对中央角膜厚度测量的影响

    Institute of Scientific and Technical Information of China (English)

    曾原; 李懿

    2015-01-01

    目的:评价复方托吡卡胺眼液对中央角膜厚度测量的影响及影响持续的时间。方法选择拟行激光角膜屈光手术的近视眼患者120例240眼,分别于点眼前和点眼后1,4 h 用 OrbscanⅡ眼前节检查系统和非接触反射显微镜SP-2000P测量角膜厚度。结果以OrbscanⅡ测量复方托吡卡胺点眼前、点眼后1 h、点眼后4 h中央角膜厚度(CCT)分别为(545±27),(559±31),(544±26)μm;以SP-2000P测量分别为(508±26),(521±29),(506±24)μm。复方托吡卡胺点眼后1 h与点眼前与相比,2种仪器测量CCT均增加( P<0.01);复方托吡卡胺点眼后4 h 与点眼后1 h 相比,2种仪器测量 CCT 均下降( P <0.01);复方托吡卡胺点眼后4 h与点眼前相比,CCT均无变化。结论复方托吡卡胺点眼1 h后使CCT增加;复方托吡卡胺对CCT影响在点眼4 h后消除。准分子激光屈光手术术前检查中,CCT的测量应在复方托吡卡胺点眼前或者点眼后4h进行。%Objective To evaluate the effect of compound tropicamide eye drops on the measurement of central corneal thickness and to investi-gate the duration of the effect.Methods In this trial, 240 eyes of 120 myopic patients undergoing corneal laser refractive surgery were selected, and central corneal thicknesses were measured before treatment and 1 , 4 h after administration of compound tropicamide eye drops using OrbscanⅡ anterior segment analysis system and SP -2000P non -contact specular microscope, respectively.Results The central corneal thick-ness was (545 ±27),(559 ±31) and (544 ±26) μm before and 1 and 4 h after administration, measured with Orbscan Ⅱ anterior segment analysis system, whereas being ( 508 ± 26 ) , ( 521 ±29 ) and (506 ±24) μm measured with SP -2000P non -contact specular microscope.The central corneal thickness measured with both OrbscanⅡsystem and SP-2000 P microscope increased 1 h after

  14. A comparative study of central corneal thickness (CCT and intraocular pressure (IOP in University of KwaZulu-Natal students of Black and Indian ethnicity*

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    Z. Sardiwalla

    2012-12-01

    Full Text Available Thisstudy compared central corneal thickness (CCT and intraocular pressure (IOP of Black and Indian students from the University of Kwa-Zulu-Natal. Two hundred (100 Black and 100 Indi-an participants of both genders aged 18-25 years (mean and standard deviation; 20.1±1.6 years participated in this study. CCT and IOP were measured for the right eye of each participant using a Tono-Pachymeter (NT530P and a Goldmann applanation tonometer (GAT respectively. Data was analyzed with descriptive, t-test and Pearson’s cor-relation statistics. In the total sample (N = 200, the mean CCT value was 519.5 ± 38.6 μm and CCT was higher in the Indians (526.5 ± 37.2 µm than in the Blacks (512.4 ± 38.9 µm (p = 0.01.  Also, it was higher in the females (522.3 µm than in males (516.7 µm, but the difference was insignificant (p = 0.07. The mean CCT was higher in the Indian males (520.1 µm than in the Black males (513.2 µm, but the difference was insignificant (p=0.39.  However, it was significantly higher in the Indian females (533 µm than in the Black females (511.6 µm (p = 0.003. In the total sample, the mean IOP was 14.6 mmHg and IOP was greater in Indiansthan Blacks (mean = 15.3 ± 2.9 mmHg and 13.8 ± 2.6 mmHg respectively (p = 0.01. Also, the mean IOP (N = 200 value was slightly higher in the females (14.7 mmHg than in males (14.5 mmHg (p = 0.51. The mean IOP was higher in the Indian males (15.0 mmHg than in the Black males (14.0 mmHg (p = 0.07 and the mean IOP value was higher in the Indian females (15.7 mmHg than in the Black females (13.6 mmHg (p < 0.001. The higher mean IOP value in the Indian than Black participants was attributed to the higher mean CCT values. A positive, but inconsistent association between CCT and IOP was found in this study, the coefficient in the total sample (r = 0.382, p = 0.000, in the Blacks (r = 0.196, p = 0.05 and in Indians (r = 0.498, p = 0.000. A national population study comparing CCT and IOP in the various

  15. Evaluation of corneal thickness alterations during menstrual cycle in productive age women

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    Negar Amiri Ghahfarokhi

    2015-01-01

    Full Text Available Purpose: To determine the change in corneal thickness through different phases of menstrual cycle in women who are in their productive age. Materials and Methods: Fifty healthy women with normal past medical history were enrolled in this prospective study. Central corneal thickness was measured with ultrasound pachymeter three times during a menstrual cycle: Beginning of the cycle (days 1-3, ovulation time, and at the end of cycle (days 27-32. We confirmed ovulation time with determining a peak in luteinizing hormone in urine. To avoid the diurnal variation of the corneal thickness which is well recognized, we checked all our subjects at 10 in the morning. Results: In days 1 to 3 of menstruation, mean corneal thickness was 541.40±11.36 and 540.82±11.70 microns for left and right eyes respectively. At ovulation time the mean thickness changed to 556.50±7.11 and 555.98±7.26 microns for left and right eyes respectively, and at the end of the cycle, the corneal thickness turned in to 536.38±12.83 and 535.48±13.08 microns for left and right eyes respectively. The difference of corneal thickness was statistically significant relating to the different stages of menstrual cycle. Conclusion: The thickest cornea during the menstruation cycle is achieved at the ovulation time and the thinnest at the end of the cycle and this should be taken in to account whilst plan to do a corneal refractive surgery.

  16. Estudo da correlação entre pressão intra-ocular e espessura corneana central (projeto glaucoma Intraocular pressure vs central corneal thickness:a comparative study (glaucoma project

    Directory of Open Access Journals (Sweden)

    Kenji Sakata

    2000-10-01

    Full Text Available Objetivos: Avaliar a distribuição da espessura corneana central (ECC e sua relação com a pressão intra-ocular (PIO em um grupo de pacientes e demonstrar a utilidade da paquimetria para avaliar a PIO em casos selecionados. Métodos: A espessura corneana central foi determinada em 167 pacientes com mais de 40 anos de idade (319 olhos por meio de paquimetria ultra-sônica. A pressão intra-ocular foi medida com tonômetro de aplanação de Goldmann. Resultados: A ECC média dos 319 olhos foi 0,5173 + 0,0377 mm, sendo o valor máximo 0,656 mm e o mínimo 0,430 mm. A PIO média foi 16,44 + 3,88 mmHg, a pressão máxima 30 mmHg e a pressão mínima 8 mmHg. Foi observada uma regressão linear de 0,13677 nas variáveis analisadas (p=0,0145, não havendo diferença entre sexo e idade. Dividiu-se as observações em dois grupos: grupo I -- PIO £ 21 mmHg -- com 285 olhos que apresentaram uma ECC média de 0,517 + 0,0376; e o grupo II -- PIO > 21 mmHg -- com 34 olhos que apresentaram uma ECC média de 0,519 + 0,0393. Conclusão: Observou-se uma regressão linear entre PIO e ECC, ou seja, quanto maior a ECC maior será a PIO. Demonstrou-se a utilidade da paquimetria corneana na avaliação da PIO daqueles pacientes em que esta estava falsamente aumentada ou diminuída na tonometria de aplanação, direcionando a terapêutica a pacientes realmente portadores de glaucoma.Purpose: To evaluate the distribution of the central corneal thickness (CCT and its relationship with the intraocular pressure (IOP in a group of patients and to demonstrate the usefulness of the pachymeter to evaluate IOP in selected cases. Methods: The central cornea thickness of 167 patients over 40 years old (319 eyes was determined using ultrasonic pachymetry. The intraocular pressure was measured by the "Goldmann" applanation tonometer.Results: The CCT average of the 319 eyes was 0.5173 + 0.0377mm, the maximum value being 0.656mm and the minimum value 0.430mm. The IOP average was

  17. Correlation between Corneal Thickness and Degree of Myopic Refractory Error

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    A Mortazavi

    2005-01-01

    Full Text Available Background: corneal thickness is an important factor in refractive surgeries such as Radial Keratotomy (RK, Photo Refractive Keratotomy (PRK and Laser Insitu Keratomileusis (LASIK. This study evaluated the correlation between this factor and the degree of myopic refractory error. Methods: In this cross-sectional study, 224 myopic eyes (112 patients which had undergone LASIK operation were assessed. These patients had referred to Aban Eye Clinic, Isfahan, Iran, during August and September 2002. Corneal thickness was measured by ORB SCAN Topoghraphy, and cycloplegic refraction was performed with autorefratometery and retinoscopy. Suspected keratoconus cases and hyperopic patients were excluded. Results: The patients' age was 27.2 ± 1.36 in men (N = 35 and 30.13 ± 1.04 in women (N = 77. Mean value of myopic refractory error in male patients was 5.1 ± 0.24D and in female patients was 3.8 ± 0.36D. Mean of corneal thickness was 540 ± 5.25 µM and 530 ± 5.88 µM in male and female patients respectively. There was no correlation between the degree of myopia and corneal thickness in any of the patients. Also in this research, no relations between the age and myopia were found. Right eye (P > 0.5, r = 0.124 Left eye (P > 0.5, r = 0.104. Conclusion: Based on our findings, corneal thickness and myopic refectory error do not seem to have any relations. (r = 0.039, p = 0.684. Keywords: Corneal Thickness, Cornea, Myopia, LASIK, Refractory Error

  18. Comparação entre as medidas da espessura central corneana usando a paquimetria óptica e a ultra-sônica Comparison between the measurements of central corneal thickness using optic and ultrasonic pachymeters

    Directory of Open Access Journals (Sweden)

    Aline Leonel Maimone

    2007-10-01

    Full Text Available OBJETIVOS: Comparar a medida da espessura corneana central (ECC obtida pelo paquímetro óptico Haag-Streit e a paquimetria ultrassônica DGH 500 (PachetteTM. MÉTODOS: Foram avaliados, 200 olhos de 100 pacientes utilizando-se o paquímetro óptico (PO e o ultrassônico (PU. As medidas foram realizadas na área central da córnea, respeitando a área dos 3 mm, em pacientes com córneas normais, em olhos hipermétropes, emétropes e míopes, excluindo doenças oculares, usuários de lentes de contato ou submetidos às cirurgias. RESULTADOS: A média geral da ECC medida pelo PO foi 603,8± 32,6µm, e 568,2±40,5 µm pelo PU. As comparações entre as medidas dos dois aparelhos foram realizadas ao nível de 5% de significância e a diferença entre os dois aparelhos foi 35,7±26,4 µm (p=0,0000, indicando diferença significativa entre os métodos utilizados. Não houve diferença estatística entre olhos hipermétropes, emétropes e míopes usando o PU. CONCLUSÃO: A medida da ECC é superestimada pelo PO quando comparada com o PU.PURPOSE: To compare measurements of central corneal thickness obtained using a Haag-Streit optic pachymeter and a DGH 500 (Pachette Ttm ultrasonic pachymeter in normal patients. METHODS: An evaluation was made of 200 eyes of 100 patients using Optic (PO and Ultrasonic (PU pachymeters. Measurements were made in the area of the central cornea (ECC respecting the 3.0 mm territory, in patients with normal corneas of hypermetropic, emetropic and myopic eyes. Patients with ocular diseases, ocular surgeries, and contact lens wearers, were excluded. A statistical analysis was performed using a Paired Student's t test to compare measurements between instruments at the 5% level of significance. RESULTS: The mean thickness of the ECC measured by the PO was 603.8±32.6µm and by the PU, 568.2±40.5µm. The difference between the two instruments was 35.7±26.4µm. Applying the t test with p = <5%, the difference was significant. We

  19. Biomechanical corneal changes induced by different flap thickness created by femtosecond laser

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    Fabricio W. Medeiros

    2011-01-01

    Full Text Available OBJECTIVE: To evaluate the impact of the creation of corneal flaps at different thicknesses on the biomechanical properties of swine corneas. METHOD: Twelve swine eyes were obtained to form two groups: 100 μm flap thickness and 300 μm flap thickness. Each eye was submitted to the following examinations: raster topography to investigate corneal curvature alterations, ocular response analyzer to investigate corneal hysteresis change, optical coherence tomography to measure central corneal and flap thickness and sonic wave propagation velocity as a measure of stiffness, before and immediately after flap creation. After flap amputation, surface wave velocity measurements were repeated. RESULTS: Measured flap thicknesses were statistically different for thin and thick flap groups, with an average of 108.5 + 6.9 and 307.8 + 11.5 μm respectively. Hysteresis and corneal resistance factor did not change significantly after flap creation in the thin flap group. With thicker flaps, both parameters decreased significantly from 8.0 +1.0 to 5.1 +1.5 mmHg and from 8.2 + 1.6 to 4.1 +2.5 mmHg respectively. Simulated keratometry values increased in the thick flap group (from 39.5 + 1 D to 45.9+1.2 D after flap creation but not in the thin flap group (from 40.6 + 0.6 D to 41.4+ 1.0 D. Regarding surface wave velocity analysis, the surgical procedures induced statistically lower results in some positions. CONCLUSION: In the experimental conditions established by this model, thicker flaps presented a greater biomechanical impact on the cornea.

  20. Correlation between Corneal Thickness and Degree of Myopic Refractory Error

    OpenAIRE

    A Mortazavi; K Nasrolahi

    2005-01-01

    Background: corneal thickness is an important factor in refractive surgeries such as Radial Keratotomy (RK), Photo Refractive Keratotomy (PRK) and Laser Insitu Keratomileusis (LASIK). This study evaluated the correlation between this factor and the degree of myopic refractory error. Methods: In this cross-sectional study, 224 myopic eyes (112 patients) which had undergone LASIK operation were assessed. These patients had referred to Aban Eye Clinic, Isfahan, Iran, during August and Septe...

  1. Comparison of Central Corneal Thickness Measured by AC-OCT and OCT%AC-OCT与OCT测量中央角膜厚度的比较

    Institute of Scientific and Technical Information of China (English)

    曾阳发; 刘杏; 蔡小于; 黄晶晶; 郑小萍; 李媚; 王涛; 毛真

    2007-01-01

    [目的]探讨眼前段光学相干断层扫描仪(AC-OCT)测量中央角膜厚度(CCT),并与光学相干断层扫描仪(OCT)进行比较.[方法]分别用OCT和AC-OCT的高分辨单线扫描程序(High Resolution Corneal)、角膜地形图程序(Pachymerry Map)测量30例(30只眼)正常受试者的CCT.采用配对t检验对之进行比较;用相关分析方法分析两种仪器测量值之间的相关性;随机选择1只眼分别用两种OCT仪依次重复测量CCT 10次,采用变异系数作为评判标准,比较测量的可重复性.[结果]OCT测量的CCT平均值为526.0(s=29.4)μm;AC-OCT角膜地形图程序测量的中央2 mm区域最小值、最大值和平均值的均值分别是512.6(s=31.7)μm,522.0(s=32..3)μm和515.0(s=31.7)μm,高分辨单线扫描程序测得的CCT值为518.9(s=31.1)μm;OCT测量的CCT值比AC-OCT的各测量值分别大13.3(s=5.9)μm(P=0.000);3.9(s=6.3)μm(P=0.002);11.0(s=5.9)μm(P=0.000);7.0(s=6.4)μm(P=0.000).OCTCCT与AC-OCT各CCT值有很好的相关性(rOCT-AC-OCT Min=0.987,rOCT-AC-OCT Max=0.987,rOCT-AC-OCT Mean=0.988,rOCT-AC-OCT Flap=0.986,P均=0.000).OCT测量CCT值10次的变异系数为0.67%.AC-OCT角膜地形图中央2 mm区域中的最小值、最大值和平均值以及高分辨单线扫描程序测量值的变异系数分别为0.23%,0.48%,0.20%和0.37%.[结论]OCT测量的CCT值比AC-OCT的各CCT值大,两种OCT的测量值相关性较好;AC-OCT测量CCT的可重复性稍好于OCT.

  2. Assessment of Corneal Epithelial Thickness in Asymmetric Keratoconic Eyes and Normal Eyes Using Fourier Domain Optical Coherence Tomography

    Directory of Open Access Journals (Sweden)

    S. Catalan

    2016-01-01

    Full Text Available Purpose. To compare the characteristics of asymmetric keratoconic eyes and normal eyes by Fourier domain optical coherence tomography (OCT corneal mapping. Methods. Retrospective corneal and epithelial thickness OCT data for 74 patients were compared in three groups of eyes: keratoconic (n=22 and normal fellow eyes (n=22 in patients with asymmetric keratoconus and normal eyes (n=104 in healthy subjects. Areas under the curve (AUC of receiver operator characteristic (ROC curves for each variable were compared across groups to indicate their discrimination capacity. Results. Three variables were found to differ significantly between fellow eyes and normal eyes (all p<0.05: minimum corneal thickness, thinnest corneal point, and central corneal thickness. These variables combined showed a high discrimination power to differentiate fellow eyes from normal eyes indicated by an AUC of 0.840 (95% CI: 0.762–0.918. Conclusions. Our findings indicate that topographically normal fellow eyes in patients with very asymmetric keratoconus differ from the eyes of healthy individuals in terms of their corneal epithelial and pachymetry maps. This type of information could be useful for an early diagnosis of keratoconus in topographically normal eyes.

  3. Use of Fish Scale-Derived BioCornea to Seal Full-Thickness Corneal Perforations in Pig Models.

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    Shih-Cheng Chen

    Full Text Available The aim of this study was to test the use of BioCornea, a fish scale-derived collagen matrix for sealing full-thickness corneal perforations in mini-pigs. Two series of experiments were carried out in 8 Lan-Yu and 3 Göttingen mini-pigs, respectively. A 2mm central full thickness corneal perforation was made with surgical scissors and 2mm trephines. The perforations were sealed immediately by suturing BioCornea to the wounded cornea. The conditions of each patched cornea were followed-up daily for 3 or 4 days. Status of operated eyes was assessed with slit lamp examination or optical coherence tomography (OCT. Animals were sacrificed after the study period and the corneas operated were fixated for histological examination. Both OCT imaging and handheld slit lamp observations indicated that a stable ocular integrity of the perforated corneas was maintained, showing no leakage of aqueous humor, normal depth of anterior chamber and only mild swelling of the wounded cornea. Hematoxylin and eosin staining of the patched cornea showed no epithelial ingrowths to the perforated wounds and no severe leucocyte infiltration of the stroma. The fish scale-derived BioCornea is capable to seal full-thickness corneal perforation and stabilize the integrity of ocular anterior chamber in pre-clinic mini-pig models. BioCornea seems to be a safe and effective alternative for emergency treatment of corneal perforations.

  4. Comparison of high-resolution Scheimpflug and high-frequency ultrasound biomicroscopy to anterior-segment OCT corneal thickness measurements

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    Kanellopoulos AJ

    2013-11-01

    Full Text Available Anastasios John Kanellopoulos,1,2 George Asimellis1 1Laservision.gr Eye Institute, Athens, Greece; 2New York University Medical School, New York, NY, USA Background: The purpose of this study was to compare and correlate central corneal thickness in healthy, nonoperated eyes with three advanced anterior-segment imaging systems: a high-resolution Scheimpflug tomography camera (Oculyzer II, a spectral-domain anterior-segment optical coherence tomography (AS-OCT system, and a high-frequency ultrasound biomicroscopy (HF-UBM system. Methods: Fifty eyes randomly selected from 50 patients were included in the study. Inclusion criteria were healthy, nonoperated eyes examined consecutively by the same examiner. Corneal imaging was performed by three different methods, ie, Oculyzer II, spectral-domain AS-OCT, and FH-UBM. Central corneal thickness measurements were compared using scatter diagrams, Bland-Altman plots (with bias and 95% confidence intervals, and two-paired analysis. Results: The coefficient of determination (r2 between the Oculyzer II and AS-OCT measurements was 0.895. Likewise, the coefficient was 0.893 between the Oculyzer II and HF-UBM and 0.830 between the AS-OCT and HF-UBM. The trend line coefficients of linearity were 0.925 between the Oculyzer II and the AS-OCT, 1.006 between the Oculyzer II and HF-UBM, and 0.841 between the AS-OCT and HF-UBM. The differences in average corneal thickness between the three pairs of CCT measurements were –6.86 µm between the Oculyzer II and HF-UBM, –12.20 µm between the AS-OCT and Oculyzer II, and +19.06 µm between the HF-UBM and AS-OCT. Conclusion: The three methods used for corneal thickness measurement are highly correlated. Compared with the Scheimplug and ultrasound devices, the AS-OCT appears to report a more accurate, but overally thinner corneal pachymetry. Keywords: anterior eye segment, high-frequency ultrasound biomicroscopy, optical coherence tomography, high-resolution Pentacam

  5. Comparison of central corneal thickness measured by AS-OCT, Pentacam and A-mode ultrasound%前节OCT、Pentacam及A超测量中央角膜厚度的比较

    Institute of Scientific and Technical Information of China (English)

    方一明; 王世明; 李晓霞; 林淑贤; 叶翠芬; 陈阿娜

    2013-01-01

    Objective To compare the difference of central corneal thickness (CCT) measured by anterior segment optical coherence tomography(AS-OCT),Pentacam and A-mode ultrasound.Methods AS-OCT,Pentacam and A-mode ultrasound were used to measure the CCT on 102 myopic cases (204 eyes) undergoing laser in situ keratomileusis (LASIK),and then compared the results.Resulls AS-OCT and Pentacam had better repeatability in measurement of CCT than A-mode ultrasound.The value of CCT measured by AS-OCT,Pentacam and A-mode ultrasound were (532-± 30)μm,(539 ±31)μm and (537 ±29)μm.There was a significant linear correlation in CCT measured by three measurements (P < 0.05).The regression equation of three measurements were CCT Pentacam =0.934 CCT AS-OCT +39.789,CCT Pentacam =0.875 CCT A-mode +70.194 and CCT AS-OCT =0.913 CCT Amode + 40.962.The CCT measured by AS-OCT was obvious lower than that measured by Pentacam and A-mode ultrasound,there were statistical differences (P < 0.05).Conclusions AS-OCT,Pentacam and A-mode ultrasound have different advantage of three measurements on clinical using,these instruments should not be used interchangeably for CCT measurement.%目的 比较前节OCT、Pentacam和A超测量中央角膜厚度(CCT)的差异.方法 选择近视患者102例(204眼),行角膜屈光手术前分别用前节OCT (AS-OCT) 、Pentacam和A超测量CCT,并进行统计分析.结果 前节OCT和Pentacam测量CCT的重复性高于A超;三者测得的CCT分别为(532±30) ìm、(539±31) μm和(537±29)μm;三者测量CCT均具有显著相关性(P<0.05);三者的回归方程分别为CCT Pentacam=0.934 CCT前节OCT+ 39.789、CCT Pentacam=0.875 CCT A超+70.194和CCT前节OCT=0.913 CCT A超+40.962.前节OCT测量角膜厚度的结果小于Pentacam与A超(P<0.05).结论 前节OCT、Pentacam和A超在测量角膜厚度方面各有优势,不能简单替代.

  6. Vertical and horizontal corneal epithelial thickness profile using ultra-high resolution and long scan depth optical coherence tomography.

    Directory of Open Access Journals (Sweden)

    Shuangqing Wu

    Full Text Available PURPOSE: To determine the vertical and horizontal thickness profiles of the corneal epithelium in vivo using ultra-long scan depth and ultra-high resolution spectral domain optical coherence tomography (SD-OCT. METHODS: A SD-OCT was developed with an axial resolution of ∼ 3.3 µm in tissue and an extended scan depth. Forty-two eyes of 21 subjects were imaged twice. The entire horizontal and vertical corneal epithelial thickness profiles were evaluated. The coefficient of repeatability (CoR and intraclass correlation (ICC of the tests and interobserver variability were analyzed. RESULTS: The full width of the horizontal epithelium was detected, whereas part of the superior epithelium was not shown for the covered super eyelid. The mean central epithelial corneal thickness was 52.0 ± 3.2 µm for the first measurement and 52.3 ± 3.4 µm for the second measurement (P>.05. In the central zone (0-3.0 mm, the paracentral zones (3.0-6.0 mm and the peripheral zones (6.0-10.0 mm, the mean epithelial thickness ranged from 51 to 53 µm, 52 to 57 µm, and 58 to 72 µm, respectively. There was no difference between the two tests at both meridians and in the right and left eyes (P>.05. The ICCs of the two tests ranged from 0.70 to 0.97 and the CoRs ranged from 2.5 µm to 7.8 µm from the center to the periphery, corresponding to 5.6% to 10.6% (CoR%. The ICCs of the two observers ranged from 0.72 to 0.93 and the CoRs ranged from 4.5 µm to 10.4 µm from the center to the periphery, corresponding to 8.7% to 15.2% (CoR%. CONCLUSIONS: This study demonstrated good repeatability of ultra-high resolution and long scan depth SD-OCT to evaluate the entire thickness profiles of the corneal epithelium. The epithelial thickness increases from the center toward the limbus.

  7. “In situ” corneal and contact lens thickness changes with high resolution OCT

    OpenAIRE

    González-Méijome, José Manuel; Cerviño, Alejandro; Peixoto-de-Matos, S. C.; Madrid-Costa, David; Jorge, Jorge; Ferrer-Blasco, Teresa

    2012-01-01

    Purpose: To show the utility of high resolution spectral domain optical coherence tomography (HR SOCT) for the in situ evaluation of epithelial, stromal and contact lens (CL) thickness changes under closed-eye conditions without lens removal. Settings: Clinical and Experimental Optometry Research Lab, University of Minho, Portugal. Methods: Eight young healthy patients wore a thick soft CL during 90 minutes under closed-eye conditions and measures of epithelial and stromal corneal thi...

  8. A review of corneal diameter, curvature and thickness values and influencing factors*

    Directory of Open Access Journals (Sweden)

    K. P. Mashige

    2013-12-01

    Full Text Available The cornea is an important ocular structure involved in the mediation of visual perception. It is the principal refractive surface of the eye and vision can be significantly affected by relatively small changes in its structure and parameters. Measurement of corneal parameters is important in the diagnosis and management of ocular diseasessuch as keratoconus and glaucoma, and also in the fitting of contact lenses or with refractive surgery such as Laser-Assisted in situ Keratomileusis(LASIK and photorefractive keratectomy (PRK. The human corneal diameter, anterior curvature and centre thickness as well as factors influencing them are reviewed in this article. This review will be useful to eye care professionals who routinely measure these parameters when fitting contact lenses and assessing, diagnosing as well as managing corneal and other ocular conditions. (S Afr Optom 2013 72(4 185-194

  9. Relationship between Corneal Thickness,Corneal Curva-ture,and Intraocular Pressure before and after Laser Treat-ment for Simple Myopia

    Institute of Scientific and Technical Information of China (English)

    Ahmad MA; Edrees MH; Jafarzadehpur E

    2014-01-01

    Purpose:To determine the relationship of central corneal thickness (CCT), curvature (CC), and intraocular pressure (IOP) as determinative factors for corneal biomechanics and in refractive surgery. Methods:.The study investigated 48 eyes from subjects who visited the Excimer Laser Surgery Clinic at the Department of Ophthalmology. The refractive error, IOP, CCT, and CC were measured in all participants. After 3 months, all exami-nations were repeated. Results:.Linear regression demonstrated a significant positive relationship between pre- and postoperative CCT,.CC,.and IOP values..The IOP showed a significant correlation with CCT (P=0.033) for pre-PRK, but no significant relationship was seen post-PRK. The CCT also correlated significantly with CC both pre-and post-PRK (P<0.05). Conclusion:.The IOP was significantly correlated with CCT before PRK, but its behavior differed after surgery. Nearly the same correlation was seen between CCT and CC before and after the PRK;.nevertheless,.IOP measurements should be calculated or estimated more precisely after PRK based on CCT corrections.

  10. The Influence of Soft Contact Lens Materials on the Central, Para-Central and Peripheral Corneal Endothelium

    OpenAIRE

    Lloyd McKernan, Aoife; Simo Mannion, Luisa; O'Dwyer, Veronica

    2015-01-01

    Title: The influence of soft contact lens materials on the central, para-central and peripheral corneal endothelium prior to and following two weeks cessation of soft contact lens wear. Purpose: To examine the influence of a variety of soft contact lens (SCL) materials on the central, para-central and peripheral corneal endothelium measurements, prior to and following two weeks cessation of SCL wear. Methods: Endothelial measurements were taken using the CEM-530 (Nidek, Japan) specular ...

  11. 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.

  12. Limbal stem cells: Central concepts of corneal epithelial homeostasis

    Institute of Scientific and Technical Information of China (English)

    Jinny; J; Yoon; Salim; Ismail; Trevor; Sherwin

    2014-01-01

    A strong cohort of evidence exists that supports the localisation of corneal stem cells at the limbus. The distinguishing characteristics of limbal cells as stem cells include slow cycling properties, high proliferative potential when required, clonogenicity, absence of differentiation marker expression coupled with positive expression of progenitor markers, multipotency, centripetal migration, requirement for a distinct niche environment and the ability of transplanted limbal cells to regenerate the entire corneal epithelium. The existence of limbal stem cells supports the prevailing theory of corneal homeostasis, known as the XYZ hypothesis where X represents proliferation and stratification of limbal basal cells, Y centripetal migration of basal cells and Z desquamation of superficial cells. To maintain the mass of cornea, the sum of X and Y must equal Z and very elegant cell tracking experiments provide strong evidence in support of this theory. However, several recent stud-ies have suggested the existence of oligopotent stem cells capable of corneal maintenance outside of the limbus. This review presents a summary of data which led to the current concepts of corneal epithelial homeostasis and discusses areas of controversy surrounding the existence of a secondary stem cell reservoir on the corneal surface

  13. Central corneal thickness in Iranian congenital glaucoma patients

    Directory of Open Access Journals (Sweden)

    Heidar Amini

    2012-01-01

    Conclusion: Patients with PCG who had controlled IOP have statistically significantly thicker corneas than nonglaucomatous age and sex-matched subjects The thicker cornea could significantly alter IOP measurement with applanation tonometry. Pachymetry should be considered an essential part of the evaluation for PCG.

  14. Central Corneal Thickness Measurement by Ultrasound versus Orbscan II

    OpenAIRE

    Amir Faramarzi; Hossein Ziai

    2008-01-01

  1. Equine corneal stromal abscesses

    DEFF Research Database (Denmark)

    Henriksen, M. D. L.; Andersen, P. H.; Plummer, C. E.;

    2013-01-01

    The last 30 years have seen many changes in the understanding of the pathogenesis and treatment of equine corneal stromal abscesses (SAs). Stromal abscesses were previously considered an eye problem related to corneal bacterial infection, equine recurrent uveitis, corneal microtrauma and corneal...... thickness lamellar keratectomy to remove the fungal hyphae and diseased stroma, followed by transplantation of healthy corneal allografts has a high rate of success in speeding healing and preserving sight. This paradigm shift in the ability to diagnose and institute therapy for corneal SAs in horses has...

  2. Corneal Laceration

    Medline Plus

    Full Text Available ... What Is Corneal Laceration? Corneal Laceration Symptoms What Causes Corneal Laceration? Corneal Laceration Diagnosis Corneal Laceration Treatment ... it will cut completely through the cornea and cause a ruptured globe, a tear in the outer ...

  3. Central corneal sensitivity after small incision lenticule extraction versus femtosecond laser-assisted LASIK for myopia: a meta-analysis of comparative studies

    OpenAIRE

    He, Miao; Huang, Wenyong; Zhong, Xingwu

    2015-01-01

    Background The aim of this study was to evaluate central corneal sensitivity after small incision lenticule extraction (SMILE) versus femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) for myopia. Methods Eligible studies were identified by systematically searching PubMed, the Cochrane Library, Embase and the Chinese Biomedicine Database. Central corneal sensitivity after SMILE versus FS-LASIK was assessed by the pooled weighted mean differences (WMDs) of the reduction from pr...

  4. Surgical compensation of presbyopia with corneal inlays.

    Science.gov (United States)

    Konstantopoulos, Aris; Mehta, Jodhbir S

    2015-05-01

    Presbyopia, the physiological change in near vision that develops with ageing, gradually affects individuals older than 40 years and is a growing cause of visual disability due to ageing demographics of the global population. The routine use of computers and 'smartphones', combined with the affluence of the 'baby boomers' generation has set high standards for near vision correction. Corneal inlays are a relatively new treatment modality that is effective at compensating for presbyopia. The dimensions of these devices vary from 2 to 3.8 mm in diameter and 5 to 32 μm in thickness. They are implanted in the anterior corneal stroma of the non-dominant eye, most commonly, in a femtosecond laser created corneal pocket. They improve near vision by increasing the depth of focus, creating a hyper-prolate region of increased central cornea power or providing a refractive add power. This article reviews the literature on the efficacy and safety of corneal inlays. PMID:25652889

  5. Corneal Laceration

    Medline Plus

    Full Text Available ... Causes Corneal Laceration? Corneal Laceration Diagnosis Corneal Laceration Treatment What Is Corneal Laceration? Written by: Kierstan Boyd ... you get medical attention. DO NOT rinse with water. DO NOT remove the object stuck in eye. ...

  6. Posterior Corneal Surface Stability after Femtosecond Laser-Assisted Keratomileusis

    Directory of Open Access Journals (Sweden)

    Carlo Cagini

    2015-01-01

    Full Text Available The purpose of this study was to evaluate posterior corneal surface variation after femtosecond laser-assisted keratomileusis in patients with myopia and myopic astigmatism. Patients were evaluated by corneal tomography preoperatively and at 1, 6, and 12 months. We analyzed changes in the posterior corneal curvature, posterior corneal elevation, and anterior chamber depth. Moreover, we explored correlation between corneal ablation depth, residual corneal thickness, percentage of ablated corneal tissue, and preoperative corneal thickness. During follow-up, the posterior corneal surface did not have a significant forward corneal shift: no significant linear relationships emerged between the anterior displacement of the posterior corneal surface and corneal ablation depth, residual corneal thickness, or percentage of ablated corneal tissue.

  7. Recovery of Corneal Endothelial Cells from Periphery after Injury.

    Directory of Open Access Journals (Sweden)

    Sang Ouk Choi

    Full Text Available Wound healing of the endothelium occurs through cell enlargement and migration. However, the peripheral corneal endothelium may act as a cell resource for the recovery of corneal endothelium in endothelial injury.To investigate the recovery process of corneal endothelial cells (CECs from corneal endothelial injury.Three patients with unilateral chemical eye injuries, and 15 rabbit eyes with corneal endothelial chemical injuries were studied. Slit lamp examination, specular microscopy, and ultrasound pachymetry were performed immediately after chemical injury and 1, 3, 6, and 9 months later. The anterior chambers of eyes from New Zealand white rabbits were injected with 0.1 mL of 0.05 N NaOH for 10 min (NaOH group. Corneal edema was evaluated at day 1, 7, and 14. Vital staining was performed using alizarin red and trypan blue.Specular microscopy did not reveal any corneal endothelial cells immediately after injury. Corneal edema subsided from the periphery to the center, CEC density increased, and central corneal thickness decreased over time. In the animal study, corneal edema was greater in the NaOH group compared to the control at both day 1 and day 7. At day 1, no CECs were detected at the center and periphery of the corneas in the NaOH group. Two weeks after injury, small, hexagonal CECs were detected in peripheral cornea, while CECs in mid-periphery were large and non-hexagonal.CECs migrated from the periphery to the center of the cornea after endothelial injury. The peripheral corneal endothelium may act as a cell resource for the recovery of corneal endothelium.

  8. Evaluation of Corneal Topography and Biomechanical Parameters after Use of Systemic Isotretinoin in Acne Vulgaris

    Directory of Open Access Journals (Sweden)

    Yusuf Yildirim

    2014-01-01

    Full Text Available Purpose. We report the effect of isotretinoin on corneal topography, corneal thickness, and biomechanical parameters in patients with acne vulgaris. Method. Fifty-four eyes of 54 patients who received oral isotretinoin for treatment of acne vulgaris were evaluated. All patients underwent a corneal topographical evaluation with a Scheimpflug camera combined with Placido-disk (Sirius, ultrasonic pachymetry measurements, and corneal biomechanical evaluation with an ocular response analyzer at baseline, in the 1st, 3rd, and 6th months of treatment, and 6 months after isotretinoin discontinuation. Results. The thinnest corneal thickness measured with Sirius differed significantly in the 1st, 3rd, and 6th months compared with the baseline measurement; there was no significant change in ultrasonic central corneal thickness measurements and biomechanical parameters (corneal hysteresis and corneal resistance factor throughout the study. Average simulated keratometry and surface asymmetry index increased significantly only in the first month of treatment according to the baseline. All changes disappeared 6 months after the end of treatment. Conclusion. Basal tear secretion and corneal morphologic properties were significantly influenced during the systemic isotretinoin treatment and the changes were reversible after discontinuation. No statistical important biomechanical differences were found to be induced by isotretinoin.

  9. The influence of corneal astigmatism on retinal nerve fiber layer thickness and optic nerve head parameter measurements by spectral-domain optical coherence tomography

    OpenAIRE

    Liu Lin; Zou Jun; Huang Hui; Yang Jian-guo; Chen Shao-rong

    2012-01-01

    Abstract Background To evaluate the influence of corneal astigmatism (CA) on retinal nerve fiber layer (RNFL) thickness and optic nerve head(ONH) parameters measured with spectral-domain optical coherence tomography (OCT) in high myopes patients before refractive surgery. Methods Seventy eyes of 35 consecutive refractive surgery candidates were included in this study. The mean age of the subjects was 26.42 ± 6.95 years, the average CA was −1.17 diopters (D; SD 0.64; range −0.2 to-3.3D), All s...

  10. Morphological evaluation of normal human corneal epithelium

    DEFF Research Database (Denmark)

    Ehlers, Niels; Heegaard, Steffen; Hjortdal, Jesper; Ivarsen, Anders; Nielsen, Kim; Prause, Jan Ulrik

    2010-01-01

    PURPOSE: The human corneal epithelium is usually described as a 50-µm-thick layer of regular stratified squamous non-keratinized cells with a thickness of 5-7 cells. The purpose of this study is systemically to revisit the histopathological appearance of 100 corneas. METHODS: 5-µm-thick sections of...... corneas from 100 consecutively selected paraffin-embedded eyes were stained with hematoxylin-eosin and Periodic Acid-Schiff (PAS). All specimens were evaluated by light microscopy. The eyes were enucleated from patients with choroidal melanoma. Corneas were considered to be normal. RESULTS: Ninety of 100...... eyes were evaluated. The central epithelial, stromal and total corneal thickness was measured as 36.0 µm, 618 µm and 651µm, respectively, with a variation coefficient from 0.21 to 0.22. Pathological appearances were found in 27% of corneas, including thickened basement membrane and alterations in...

  11. 超高分辨率OCT角膜上皮厚度自动测量的重复性研究%Study of repeatability of corneal epithelium thickness profiles automatically measured by ultra -high resolution OCT system

    Institute of Scientific and Technical Information of China (English)

    徐肃仲; 叶欣杰; 许哲; 杨纯; 沈梅晓

    2013-01-01

    目的:研究基于自动分层算法的超高分辨率谱域 OCT ( UHR-OCT)用于角膜上皮厚度测量的重复性。  方法:使用自行搭建的UHR-OCT系统采集18例健康受试者(年龄23.2±0.9岁)左眼的图像,应用一种基于轴向梯度信息和最短路径的分层算法对得到的SD-OCT图像进行边界探测获取角膜上皮厚度。  结果:自动与手动的上皮分层的位置有很好的相关性(P>0.05,配对t检验)。自动算法获取的6 mm范围平均上皮厚度为52.1±2.1μm,范围从50.3±1.8μm 到53.2±2.4μm,与手动分层之间的角膜上皮厚度差异为0.4±0.3μm。UHR-OCT自动算法重复测量上皮厚度的组内相关系数ICC和可重复性系数CoR分别为0.90±0.05,1.44±0.01μm。  结论:对于超高分辨率OCT,自动分层方法在角膜上皮厚度测量中有着很好的准确性和可重复性。%AIM:To assess the repeatability of thickness profiles of corneal epithelium produced by aautomatic hierarchic algorithm that was applied to images obtained by a custom-built ultra-high resolution OCT ( UHR-OCT ) system. METHODS:Eighteen left eyes of 18 subjects (23.2±0.9) years;mean age±standard deviation) were imaged twice on non-consecutive days by a custom-built ultra-high resolution OCT ( UHR -OCT ) system. A hierarchic algorithm based on the axial gradient information and a shortest path search was developed to measure the corneal epithelial thickness profiles from the SD-OCT images. RESULTS: There was good correlation between theautomatic and manual hierarchy positions of the epithelium ( p >0.05, paired t -test ). The average epithelial thickness of the 6mm central corneal region determined by the automatic hierarchic algorithm was 52.1±2.1μm, ranging from 50.3 ±1.8μm to 53.2 ±2.4μm along the horizontal meridian. The epithelial thickness differences between automatic and manual hierarchy by the UHR-OCT systems were 0.4 ±0

  12. Corneal endothelial morphology and central thickness in patients with type II diabetes mellitus

    DEFF Research Database (Denmark)

    Storr-Paulsen, Allan; Singh, Amardeep; Jeppesen, Helene; Norregaard, Jens C; Thulesen, Jesper

    2014-01-01

    size was based on a power calculation (power = 0.90; p = 0.05). The diabetic patients had on average more than four HbA1c tests performed (mean 4.1; range 2-14) with intervals of at least 3 months as a reflection of the long-term glycaemic status. The controls had no diabetes confirmed by two causal...

  13. Changes in corneal structure with continuous wear of High-Dk Soft contact lenses : a pilot study

    OpenAIRE

    González-Méijome, José Manuel; González-Pérez, Javier; Cerviño, Alejandro; Yebra-Pimentel Vilar, Eva; Parafita, Manuel A.

    2003-01-01

    Despite numerous studies that have considered the effects of extended wear of high-Dk soft contact lenses on ocular physiology, little attention has been paid to the impact of such lenses on central or peripheral corneal thickness and curvature. The present study aims to report the time course of changes in corneal thickness and curvature that accompanies the 30-night continuous wear of new silicone hydrogel soft contact lenses in a neophyte population in a longitudinal study. Methods. Six...

  14. Choroidal thickness following extrafoveal photodynamic treatment with verteporfin in patients with central serous chorioretinopathy

    DEFF Research Database (Denmark)

    Pryds, Anders; Larsen, Michael

    2012-01-01

    Purpose: To evaluate the effect of verteporfin photodynamic treatment (PDT) on choroidal thickness in patients with central serous chorioretinopathy (CSC). Methods: Choroidal thickness was measured with enhanced depth imaging- optical coherence tomography (EDI-OCT) before and after verteporfin PDT...

  15. Corneal Laceration

    Medline Plus

    Full Text Available ... eye or something striking the eye with significant force, like a metallic hand tool. A corneal laceration is deeper than a corneal abrasion , cutting ... with Industry Medical Disclaimer Privacy Policy Terms of Service For ...

  16. Corneal Laceration

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    Full Text Available ... Health Find an Ophthalmologist Academy Store Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask an Ophthalmologist Español Eye Health / Eye Health A-Z Corneal Laceration Sections What Is Corneal Laceration? Corneal ...

  17. Corneal tissue water content mapping with THz imaging: preliminary clinical results (Conference Presentation)

    Science.gov (United States)

    Sung, Shijun; Bajwa, Neha; Deng, Sophie X.; Taylor, Zachary; Grundfest, Warren

    2016-03-01

    Well-regulated corneal water content is critical for ocular health and function and can be adversely affected by a number of diseases and injuries. Current clinical practice limits detection of unhealthy corneal water content levels to central corneal thickness measurements performed by ultrasound or optical coherence tomography. Trends revealing increasing or decreasing corneal thickness are fair indicators of corneal water content by individual measurements are highly inaccurate due to the poorly understood relationship between corneal thickness and natural physiologic variation. Recently the utility of THz imaging to accuarately measure corneal water content has been explored on with rabbit models. Preliminary experiments revealed that contact with dielectric windows confounded imaging data and made it nearly impossible to deconvolve thickness variations due to contact from thickness variations due to water content variation. A follow up study with a new optical design allowed the acquisition of rabbit data and the results suggest that the observed, time varying contrast was due entirely to the water dynamics of the cornea. This paper presents the first ever in vivo images of human cornea. Five volunteers with healthy cornea were recruited and their eyes were imaged three times over the course of a few minutes with our novel imaging system. Noticeable changes in corneal reflectivity were observed and attributed to the drying of the tear film. The results suggest that clinically compatible, non-contact corneal imaging is feasible and indicate that signal acquired from non-contact imaging of the cornea is a complicated coupling of stromal water content and tear film.

  18. The influence of corneal astigmatism on retinal nerve fiber layer thickness and optic nerve head parameter measurements by spectral-domain optical coherence tomography

    Directory of Open Access Journals (Sweden)

    Liu Lin

    2012-05-01

    Full Text Available Abstract Background To evaluate the influence of corneal astigmatism (CA on retinal nerve fiber layer (RNFL thickness and optic nerve head(ONH parameters measured with spectral-domain optical coherence tomography (OCT in high myopes patients before refractive surgery. Methods Seventy eyes of 35 consecutive refractive surgery candidates were included in this study. The mean age of the subjects was 26.42 ± 6.95 years, the average CA was −1.17 diopters (D; SD 0.64; range −0.2 to-3.3D, All subjects in this study were WTR CA. 34 eyes were in the normal CA group with a mean CA was −0.67 ± 0.28D, 36 eyes were in the high CA group with an average CA of −1.65 ± 0.49D. All subjects underwent ophthalmic examination and imaging with the Cirrus HD OCT. Results No significant difference was noted in the average cup-to-disk ratio, vertical cup-to-disk ratio and cup volume (all P values > 0.05. Compared with the normal CA group, the high CA group had a larger disc area and rim area, thinner RNFL thickness in the temporal quadrant, and the superotemporal and inferotemporal peaks were farther to the temporal horizon (All P values P values > 0.05. Conclusions The degree of with-the-rule CA should be considered when interpreting ONH parameters and peripapillary RNFL thickness measured by the Cirrus HD OCT. Virtual slides The virtual slide(s for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1148475676881895

  19. Change in corneal curvature induced by surgery

    OpenAIRE

    Rij, Gabriel

    1987-01-01

    textabstractThe first section deals with the mechanisms by which sutures, incisions and intracorneal contact lenses produce a change in corneal curvature. To clarify the mechanisms by which incisions and sutures produce astigmatism, we made incisions and placed sutures in the corneoscleral limbus of human eye bank eyes (chapter 2). The changes in corneal curvature were studied by central keratometry and by shadowgraph photography of the corneal contour. A radial corneal suture induces astigma...

  20. Application of corneal tomography before keratorefractive procedure for laser vision correction.

    Science.gov (United States)

    Luz, Allan; Lopes, Bernardo; Salomão, Marcela; Ambrósio, Renato

    2016-05-01

    Ectasia after refractive surgery represents a major concern among refractive surgeons. Corneal abnormalities and preexisting corneal ectasia are the most important risk factors. Corneal topography and central corneal thickness are the factors traditionally screening for in refractive surgery candidates. Study of the anterior surface by Placido topography allows for identification of keratoconus before biomicroscopy. However, this is insufficient for the evaluation of pre-operative refractive surgery. There are cases of ectasia after laser in situ keratomilusis (LASIK) without identifiable risk factors such that there is a need to go beyond the corneal surface. A key requirement is quantifying susceptibility to corneal biomechanical instability and progression to ectasia. Tomographic indices derived from elevation maps and pachymetry spatial variation produce a Belin Ambrosio display final D index (BAD-D index), which has shown better results compared to surface curvature indices for detecting very mild forms of ectasia. A logistic regression formula, integrating age, residual stromal bed, and BAD-D (Ectasia Susceptibility Score, ESS) resulted in a significant improvement in accuracy, leading to 100% sensitivity and 94% specificity for detecting susceptible cases. A comprehensive corneal structural analysis based on corneal segmental tomography can detect susceptible corneas, which increases safety for refractive surgery patients. PMID:27079610

  1. Role of Optical Coherence Tomography on Corneal Surface Laser Ablation

    Directory of Open Access Journals (Sweden)

    Bruna V. Ventura

    2012-01-01

    Full Text Available This paper focuses on reviewing the roles of optical coherence tomography (OCT on corneal surface laser ablation procedures. OCT is an optical imaging modality that uses low-coherence interferometry to provide noninvasive cross-sectional imaging of tissue microstructure in vivo. There are two types of OCTs, each with transverse and axial spatial resolutions of a few micrometers: the time-domain and the fourier-domain OCTs. Both have been increasingly used by refractive surgeons and have specific advantages. Which of the current imaging instruments is a better choice depends on the specific application. In laser in situ keratomileusis (LASIK and in excimer laser phototherapeutic keratectomy (PTK, OCT can be used to assess corneal characteristics and guide treatment decisions. OCT accurately measures central corneal thickness, evaluates the regularity of LASIK flaps, and quantifies flap and residual stromal bed thickness. When evaluating the ablation depth accuracy by subtracting preoperative from postoperative measurements, OCT pachymetry correlates well with laser ablation settings. In addition, OCT can be used to provide precise information on the morphology and depth of corneal pathologic abnormalities, such as corneal degenerations, dystrophies, and opacities, correlating with histopathologic findings.

  2. Comparison of Corneal Topographical and Biomechanical Properties in Cases with Atopic Dermatitis and Healthy Subjects

    Directory of Open Access Journals (Sweden)

    Yusuf Yıldırım

    2013-06-01

    Full Text Available Pur po se: To compare the topographic, biomechanical, and thickness properties of corneas of patients with atopic dermatitis (AD and of healthy individuals. Ma te ri al and Met hod: In this prospective, cross-sectional, and comparative study, 28 healthy individuals (control group and 28 patients with AD (study group were enrolled. Corneal topographical measurements using Scheimpflug camera with a Placido disc topographer (Sirius, corneal biomechanical properties using Ocular Response Analyzer (ORA, and central corneal thickness (CCT using ultrasonic pachymeter were obtained for each participant. Re sults: Topographic parameters were not significantly different between both groups (p>0.05. Corneal hysteresis (CH and corneal resistance factor (CRF were found same in both groups. CCT measured with ultrasonic pachymeter was significantly lower in patients with AD compared to health controls (p<0.05. Dis cus si on: No significant difference was found between patients with AD and age-matched healthy individuals regarding the corneal topographic findings and corneal biomechanical parameters. CCT was found to be lower in cases with AD than in healthy controls. (Turk J Ophthalmol 2013; 43: 140-4

  3. Corneal amyloidosis associated with keratoconus.

    Science.gov (United States)

    Stern, G A; Knapp, A; Hood, C I

    1988-01-01

    Nodular, gray-white, central corneal opacities which extended from the subepithelial zone through the anterior four fifths of the stroma developed in a 50-year-old man with a longstanding history of hard contact lens wear for keratoconus. Results of histopathologic analysis of the corneal button obtained at the time of penetrating keratoplasty disclosed that the opacities were composed of amyloid. Corneal amyloidosis is rarely found in association with keratoconus. Although there were some similarities in the pattern of amyloid deposition to that seen in primary familial amyloidosis of the cornea, the authors believe that their patient is more likely to have had a secondary amyloidosis. Corneal amyloidosis should be considered in keratoconus patients with development of unusual forms of central corneal opacification. PMID:3278260

  4. [Influence of corneal transparency on the quality of topographies].

    Science.gov (United States)

    Franko Zeitz, P; Kohlhaas, M

    2012-12-01

    Corneal topographs that measure the anterior and posterior corneal surface with optical methods need a clear cornea for precise measurements. Opacities cause artifacts in the corneal thickness (with measurements usually being too thin) and corneal curvatures. This is important to know as certain pathologies may repeatedly cause similar artifacts. This is highly relevant after a corneal cross-linking, Lasek or PRK, as these procedures cause typical artifacts that can easily be misinterpreted. PMID:23258670

  5. SURGICAL OUTCOME OF TRIPLE PROCEDURE AS PENETRATING KERATOPLASTY WITH EXTRACAPSULAR CATARACT EXTRACTION WITH POSTERIOR CHAMBER INTRAOCULAR LENS IMPLANTATION IN PATIENTS WITH BOTH CENTRAL CORNEAL OPACITY AND ADVANCED CATARACT AT RURAL SET UP

    OpenAIRE

    Shubhangi Nigwekar, Kishor Badhe, Neeta Misra, Surekha Bangal

    2015-01-01

    Purpose: To study the surgical outcome of triple procedure as penetrating keratoplasty (PKP) with conventional extra capsular cataract extraction (ECCE) with posterior chamber intraocular lens (PCIOL) implantation in patients with both central corneal opacity and advanced cataract at rural set up. Introduction: When corneal opacity and cataract present together then well-established and effective triple procedure is indicated. Prognosis for a clear graft is good in triple, as graft endothe...

  6. Colour of the nucleus as a marker of nuclear hardness, diameter and central thickness

    OpenAIRE

    Gullapalli Vamsi; Murthy Praveen; Murthy K

    1995-01-01

    Hundred and thirty patients, aged above 40 years, with senile cataract were examined. Age and colour were selected as the probable preoperative indicators of nuclear hardness. The lens material collected after manual extracapsular extraction was washed and the nucleus isolated. The diameter and central thickness of the nucleus were measured; the mean diameter and mean central thickness were 7.13 mm ± 0.76 and 3.05 mm ± 0.48, respectively. The hardness of the nucleus was measured...

  7. Kinetics of central macular thickness reduction in patients with macular edema after intravitreal drug therapy

    Directory of Open Access Journals (Sweden)

    He L

    2011-12-01

    Full Text Available Lingmin He, Annie Chan, Theodore Leng, Mark S BlumenkranzDepartment of Ophthalmology, Stanford University School of Medicine, Stanford, California, USABackground: The purpose of this study was to characterize central macular thickness and retinal volume following intravitreal injections using time domain and spectral domain optical coherence tomography (TD-OCT and SD-OCT, respectively.Methods: Nine patients with macular edema secondary to diabetes or retinal vein occlusion treated with intravitreal triamcinolone 4.0 mg and/or bevacizumab 1.25 mg were enrolled. Central macular thickness and volume was measured by SD-OCT and TD-OCT scan at baseline, and 1, 3, 6, 24, 48 hours, and 1 week postinjection.Results: Equations were derived to describe central macular thickness and volume reduction in the hours following intravitreal injection. Measurements of central macular thickness by SD-OCT were significantly reduced by 3 hours (P = 0.03 and retinal volume by 6 hours (P = 0.03. Central macular thickness measured 40.9 (28.6–53.2 µm thicker on the SD-OCT instrument while volume measured 3.47 (3.27–3.66 mm3 higher.Conclusion: Significant central macular thickness and volume reductions occur in the first hours after injection with triamcinolone and/or bevacizumab.Keywords: retinal vein occlusion, intravitreal injection, diabetic retinopathy

  8. In Vivo Corneal Biomechanical Properties with Corneal Visualization Scheimpflug Technology in Chinese Population

    Directory of Open Access Journals (Sweden)

    Ying Wu

    2016-01-01

    Full Text Available Purpose. To determine the repeatability of recalculated corneal visualization Scheimpflug technology (CorVis ST parameters and to study the variation of biomechanical properties and their association with demographic and ocular characteristics. Methods. A total of 783 healthy subjects were included in this study. Comprehensive ophthalmological examinations were conducted. The repeatability of the recalculated biomechanical parameters with 90 subjects was assessed by the coefficient of variation (CV and intraclass correlation coefficient (ICC. Univariate and multivariate linear regression models were used to identify demographic and ocular factors. Results. The repeatability of the central corneal thickness (CCT, deformation amplitude (DA, and first/second applanation time (A1/A2-time exhibited excellent repeatability (CV% ≤ 3.312% and ICC ≥ 0.929 for all measurements. The velocity in/out (Vin/out, highest concavity- (HC- radius, peak distance (PD, and DA showed a normal distribution. Univariate linear regression showed a statistically significant correlation between Vin, Vout, DA, PD, and HC-radius and IOP, CCT, and corneal volume, respectively. Multivariate analysis showed that IOP and CCT were negatively correlated with Vin, DA, and PD, while there was a positive correlation between Vout and HC-radius. Conclusion. The ICCs of the recalculated parameters, CCT, DA, A1-time, and A2-time, exhibited excellent repeatability. IOP, CCT, and corneal volume significantly influenced the biomechanical properties of the eye.

  9. Corneal Laceration

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    Full Text Available ... about eye health and preserving your vision. Privacy Policy Related Corneal Collagen Cross-linking Approved to Treat ... Academy Financial Relationships with Industry Medical Disclaimer Privacy Policy Terms of Service For Advertisers For Media Ophthalmology ...

  10. Corneal Laceration

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    Full Text Available ... itself. A corneal laceration is a very serious injury and requires immediate medical attention to avoid severe ... 27, 2015 Dark Spot in Vision After Blunt Trauma Dec 21, 2014 Pain a Year After Eyelid ...

  11. Corneal Laceration

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    Full Text Available ... drugs. These drugs thin the blood and may increase bleeding. After you have finished protecting the eye, ... that I’m older, will a corneal transplant help me? May 15, 2015 Why Do My Eyes ...

  12. Corneal transplant

    Science.gov (United States)

    ... clear outer lens on the front of the eye. A corneal transplant is surgery to replace the cornea with tissue ... years. Rejection can sometimes be controlled with steroid eye drops. Other ... are: Bleeding Cataracts Infection of the eye Glaucoma ( ...

  13. Management of inflammatory corneal melt leading to central perforation in children: a retrospective study and review of literature.

    Science.gov (United States)

    Medsinge, A; Gajdosova, E; Moore, W; Nischal, K K

    2016-04-01

    PurposeTo assess the outcome of early therapeutic penetrating keratoplasty (PKP) for corneal melt leading to perforation in children.MethodsCase notes of all the consecutive patients presenting with acute corneal perforation that underwent urgent therapeutic PKP between 2000 and 2010 to the practice of one of the authors, both NHS at Great Ormond Street Hospital for Children and private, were retrospectively reviewed. Onset of perforation, underlying cause, medical and surgical treatment, pre- and post-operative visual acuity, graft clarity, length of follow-up, and post-operative complications were recorded.ResultsFour eyes of four consecutive patients (mean age of 9.5 years and median 8.5 years, range 4-17 years) were treated for acquired acute onset corneal perforations. There were three females and one male. Etiologies included herpes simplex keratitis secondary to immune recovery disease post bone marrow transplantation, acanthamoeba keratitis, recessive dystrophic epidermolysis bullosa, and blepharokeratoconjunctivitis with acne rosacea. Pre-operative visual acuity ranged from hand movements to 6/150. All the patients had severe anterior chamber inflammation. All eyes improved in visual acuity ranging from 6/9 to 6/18 with clear grafts at last follow-up. There was no recurrence of melt or perforation. Mean follow-up was 67 months (median 44 months).ConclusionPKP during the acute phase together with aggressive medical therapy and close follow-up may achieve good visual outcomes in children with corneal melt with perforation and should be considered. Waiting may sometimes allow the marked inflammatory response seen in children to cause irreversible structural and/or functional damage. PMID:26821761

  14. Sunitinib inhibits inflammatory corneal lymphangiogenesis.

    OpenAIRE

    Detry, Benoît; Blacher, Silvia; Erpicum, Charlotte; Paupert, Jenny; Maertens, Ludovic; Maillard, Catherine; Munaut, Carine; Sounni, Nor Eddine; Lambert, Vincent; Foidart, Jean-Michel; Rakic, Jean-Marie; Cataldo, Didier; Noël, Agnès

    2013-01-01

    PURPOSE: To evaluate the antilymphangiogenic potential of multi-target tyrosine kinase inhibitor sunitinib in corneal neovascularization (NV). METHODS: Inflammatory corneal NV was induced by thermal cauterization applied in the central cornea of mice, to which sunitinib malate was daily administered by gavage or not. At days 6, 11, or 17 post cauterization, lymphatic and blood vessels, as well as inflammatory cells were immunostained and quantified in whole-mounted corneas. RT-PCRs were perfo...

  15. Therapeutic efficiency of tissue-engineered human corneal endothelium transplants on rabbit primary corneal endotheliopathy

    Institute of Scientific and Technical Information of China (English)

    Ting-jun FAN; Jun ZHAO; Xiu-zhong HU; Xi-ya MA; Wen-bo ZHANG; Chao-zhong YANG

    2011-01-01

    To evaluate the therapeutic efficiency of tissue-engineered human corneal endothelia (TE-HCEs) on rabbit primary corneal endotheliopathy (PCEP), TE-HCEs reconstructed with monoclonal human corneal endothelial cells (mcHCECs) and modified denuded amniotic membranes (mdAMs) were transplanted into PCEP models of New Zealand white rabbits using penetrating keratoplasty. The TE-HCEs were examined using diverse techniques including slit-lamp biomicroscopy observation and pachymeter and tonometer measurements in vivo, and fluorescent microscopy, alizarin red staining, paraffin sectioning, scanning and transmission electron microscopy observations in vitro. The corneas of transplanted eyes maintained transparency for as long as 200 d without obvious edema or immune rejection. The corneal thickness of transplanted eyes decreased gradually after transplanting, reaching almost the thickness of normal eyes after 156 d, while the TE-HCE non-transplanted eyes were turbid and showed obvious corneal edema. The polygonal corneal endothelial cells in the transplanted area originated from the TE-HCE transplant. An intact monolayer corneal endothelium had been reconstructed with the morphology, cell density and structure similar to those of normal rabbit corneal endothelium. In conclusion, the transplanted TE-HCE can reconstruct the integrality of corneal endothelium and restore corneal transparency and thickness in PCEP rabbits. The TE-HCE functions normally as an endothelial barrier and pump and promises to be an equivalent of HCE for clinical therapy of human PCEP.

  16. Corneal Transplantation

    DEFF Research Database (Denmark)

    Hjortdal, Jesper Østergaard

    . Economic considerations on cost and benefi t of medical treatment and surgical procedures are today an integrated part of the health system in many countries, and a chapter covers these aspects of corneal transplantation. This textbook is aimed at presenting an updated review of the new techniques...... with less risk of rejection episodes. Besides covering updated chapters on penetrating keratoplasty, and anterior and posterior lamellar procedures, this textbook also gives a thorough overview of the history of corneal transplantation and a detailed presentation of the microstructural components...

  17. Corneal Laceration

    Medline Plus

    Full Text Available ... Tips & Prevention News Ask an Ophthalmologist Patient Stories Español Eye Health / Eye Health A-Z Corneal Laceration ... without Eye Protection Jun 19, 2014 Leer en Español: ¿Qué Es una Laceración de la Córnea? Find ...

  18. Corneal Laceration

    Medline Plus

    Full Text Available ... Glasses & Contacts Tips & Prevention News Ask an Ophthalmologist Español Eye Health / Eye Health A-Z Corneal Laceration ... without Eye Protection Jun 19, 2014 Leer en Español: ¿Qué Es una Laceración de la Córnea? Find ...

  19. Analysis of low-energy and high-frequency femtosecond laser for the construction of deep anterior donor corneal lamellae

    Directory of Open Access Journals (Sweden)

    Gustavo Victor

    2014-04-01

    Full Text Available Purpose: To evaluate the efficacy and reliability of a low-energy femtosecond laser with a high repetition rate for construction of deep anterior donor corneal lamellae. Methods: This was a prospective laboratory investigation. Twenty-five human corneal buttons were femtosecond laser cut to create thick anterior lamellae (diameter, 10mm; thickness, 500µm. The laser cuts were made using an LDV® femtosecond laser in a Ziemer® anterior chamber. To obtain a better edge, the lamellae were trephined with an 8mm trephine (Katena®. The central corneal thickness and the anterior lamellae were measured using a Mitutoyo® thickness gauge with an accuracy of 0.001mm. Results: The central thickness of the 25 corneas ranged from 500 to 705µm (mean, 584 ± 51µm. The thickness of the anterior lamellae ranged from 420 to 480µm (mean, 455 ± 12.7µm. The anterior lamellae diameters were 7.90 ± 0.1mm, and all laser cuts were round. The lamellar interfaces appeared regular by surgical microscopy. There were no cases of inter-lamellar adhesion. Conclusion: The LDV® femtosecond laser appears to be a safe and reliable instrument for cutting deep anterior lamellae from donor corneoscleral buttons. Minimal variation in donor lamellar depth with the laser will be useful for creating donor corneal tissue for deeper anterior lamellar keratoplasty or endothelial keratoplasty surgery or both from a single donor cornea.

  20. The Long-Term Effects of Silicone Hydrogel Contact Lens Wear on Corneal Morphology

    OpenAIRE

    Yelda Yıldız; Canan Gürdal; Özge Saraç; Şenay Aşık Nacaroğlu; Tamer Takmaz; İzzet Can

    2012-01-01

    Pur po se: To evaluate the effects of silicone hydrogel contact lenses (SHCL) on central corneal thickness (CCT), corneal endothelial cell morphology, and tear functions. Ma te ri al and Met hod: Fifty-five eyes of 28 SHCL wearers (Group 1) and 52 eyes of 26 healthy subjects (Group 2) were included in this study’. According to their contact lens wearing time, the contact lens wearing subjects were divided into 2 groups: Group 1a - wearing time less than 1 year and Group 1b - weari...

  1. Full-Thickness Retinochoroidal Incision in the Management of Central Retinal Vein Occlusion

    Directory of Open Access Journals (Sweden)

    San-Ni Chen

    2015-01-01

    Full Text Available Purpose. To evaluate the clinical outcomes in patients with central retinal vein occlusion (CRVO treated with full-thickness retinochoroidal incisions and to compare whether there is difference in treatment response in ischemic and nonischemic CRVO. Methods. Retrospective study of patients of CRVO receiving full-thickness retinochoroidal incisions in Changhua Christian Hospital. Fluorescein angiography (FA, slit-lamp biomicroscopy, indirect funduscopy, best corrected visual acuity, and central macular thickness (CMT measured by optical coherence tomography were performed pre- and postoperatively. Patients were divided into an ischemic and nonischemic group according to the findings of FA. Patients were followed up for at least 1 year. Results. Twenty-eight eyes (14 ischemic and 14 nonischemic CRVO were included. Functional retinochoroidal venous anastomosis (RCVA was achieved in 48 of the 65 retinochoroidal incisions (73.8%. Central macular thickness (CMT and retinal hemorrhage decreased significantly after the surgery. Significant visual gain was observed postoperatively in the nonischemic group, but not in the ischemic group. Postoperative complications included vitreous hemorrhage (17.8%, neovascular glaucoma (7.1%, and preretinal fibrovasular membrane (10.7%, all of which were in the ischemic group. Conclusions. RCVA formation induced by retinochoroidal incisions could improve venous flow, and decrease CMT and retinal hemorrhage. However, only eyes with nonischemic CRVO showed visual improvement.

  2. Corneal Endothelial Safety of Intracameral Preservative-free 1% Xylocaine

    Directory of Open Access Journals (Sweden)

    Shah Alpesh

    2004-01-01

    Full Text Available Purpose : To evaluate the effect of intracameral preservative-free 1% xylocaine on the corneal endothelium as an adjuvant to topical anaesthesia during phacoemulsification and Acrysof foldable IOL implantation. Material & Methods: This is a prospective, controlled, randomised, double-masked study. 106 patients with soft to moderately dense (Grade 1-3 senile cataract and corneal endothelial cell density of >1500/mm2 were randomised to the xylocaine group (n=53 and control group(n=53. Central endothelial specular microscopy and ultrasound corneal pachymetry were performed preoperatively. On the first postoperative day the eyes were evaluated for corneal oedema and Descemet′s folds. Ultrasound corneal pachymetry was performed at 1, 3 and 12 months. Specular microscopy was performed at 3 and 12 months. Cell loss was expressed as a percentage of preoperative cell density. Six patients could not complete one year follow-up. Chi-square and paired t test (2 tail statistical tests were applied for analysis. Results: Four (7.54% patients in the xylocaine group and 5 (9.43% in the control group had a few Descemet′s folds associated with mild central stromal oedema. Corneal thickness increased from 549.3µ ± 37.2µ to 555.5µ ± 36.5µ in the xylocaine group and from 553.1µ ± 36.2µ to 559.3µ ± 40.5µ in the control group at the one-month postoperative visit. Thickness returned to the preoperative level in xylocaine group 549.6µ ± 34.5µ and control group 554.7µ ± 41.1µ at three months. (P=0.484 The percentage of cell loss was 4.47 ± 2.53% in the xylocaine group and 4.49 ± 3.09 % in the control group at one year. (P=0.97 Conclusion: Intracameral preservative-free 1% xylocaine does not appear to affect corneal endothelium adversely during phacoemulsification.

  3. Changes in Corneal Biomechanical Properties after Long-Term Topical Prostaglandin Therapy

    Science.gov (United States)

    Yu, Xiaobo; Li, Mengwei; Wen, Wen; Sun, Xinghuai

    2016-01-01

    Objective To compare corneal biomechanical properties, measured by a newly developed tonometer (Corneal Visualization Scheimpflug Technology, Corvis ST), in untreated primary open angle glaucoma (POAG) patients, POAG patients with long-term topical prostaglandin analog (PGA) therapy and in normal controls. Further is to investigate the potential effects of PGA on corneal biomechanics. Methods In this case-control study, 35 consecutive medication naïve eyes with POAG, 34 POAG eyes with at least 2 years treatment by PGA and 19 normal eyes were included. Intraocular pressure (IOP), central corneal thickness (CCT) and corneal biomechanical parameters, including deformation amplitude (DA), applanation time (AT1 and AT2), applanation length (AL1 and AL2), applanation velocity (AV1 and AV2), and peak distance and radius were measured using Corvis ST. Axial length and corneal curvature were measured with partial coherence interferometry (IOLMaster, Zeiss, Germany). General linear model analysis was performed to investigate the corneal biomechanical property changes among the normal controls, newly diagnosed POAG patients and POAG patients with long-term PGA treatment, and among the subgroups of different types of PGA treatment, including bimatoprost, latanoprost and travoprost. Furthermore, pairwise comparisons using Bonferroni correction for least squares means were employed. Results AT1 (p<0.0001), AV1 (p<0.0001), AT2 (p = 0.0001), AV2 (p<0.0001) and DA (p = 0.0004) in newly diagnosed glaucoma patients were significantly different from those in normal subjects and in patients underwent at least 2 years topical PGA therapy after adjusting for age and gender. After adjusting for age, gender, IOP, CCT, axial length and corneal curvature, a significant difference was detected for DA between glaucoma patients without PGA treatment and patients with long-term PGA therapy (p = 0.0387). Furthermore, there were no statistical significant differences in all of the corneal

  4. Optovue iVue OCT测量角膜厚度的可重复性及其与Pentacam、Visante OCT的一致性研究%Repeatability of corneal thickness measurement with Optovue iVue OCT and a comparative study with Pentacam and Visante OCT

    Institute of Scientific and Technical Information of China (English)

    苏小连; 吴文静; 王雁

    2015-01-01

    Background Measurement of corneal thickness is of great significance for the design of refractive surgery and the diagnosis of eye diseases,measuring equipments and technology develop rapidly in recent years.Optovue iVue OCT is a new frequency-domain optical coherence tomography (OCT),to compare its results with those of Pentacam and Visante OCT is helpful to objectively assess the clinical value of Optovue iVue OCT.Objective This study was to investigate the repeatability of corneal thickness measurement with Optovue iVue OCT and the comparatbility with Pentacam three-dimensional anterior segment analysis diagnostic system and Visante OCT.In addition,this study attempted to analyze the distribution of average corneal thickness in each quadrant by Optovue iVue OCT.Methods The corneal thicknesses of the corneal thinnest point,the central point and 3:00,6:00,9:00,12:00 zones 1 mm away from the center of the cornea were measured in 45 right eyes of 45 subjects with myopia using Optovue iVue OCT,Pentacam and Visante OCT in Tianjin Eye Hospital.Interclass correlation coefficient (ICC) was used to analyze the repeatability of measurement by Optovue iVue OCT.The agreements between Optovue iVue OCT and Pentacam or Visante OCT were evaluated by Bland-Altman test.The corneal area of 1.0-2.5 mm away from the center was divided into eight quadrants and the average corneal thickness of each quadrant was measured and analysis with Optovue iVue OCT.Results No significant difference was found in corneal thickness values for 3 times by Optovue iVue OCT (P=0.546).The ICC by Optovue iVue OCT was 99.92%,99.99%,99.96%,99.99%,99.99% and 99.97% at the corneal thinnest point,the central point and 3:00,6:00,9:00,12:00 zones respectively.There were significant differences among the 3 kinds of methods (P =0.000,0.001,0.000,0.003,0.002,0.000).The measured values of Optovue iVue OCT were significantly lower mean 24.20 μm than those of Pentacam (P=0.000,0

  5. Colour of the nucleus as a marker of nuclear hardness, diameter and central thickness

    Directory of Open Access Journals (Sweden)

    Gullapalli Vamsi

    1995-01-01

    Full Text Available Hundred and thirty patients, aged above 40 years, with senile cataract were examined. Age and colour were selected as the probable preoperative indicators of nuclear hardness. The lens material collected after manual extracapsular extraction was washed and the nucleus isolated. The diameter and central thickness of the nucleus were measured; the mean diameter and mean central thickness were 7.13 mm ± 0.76 and 3.05 mm ± 0.48, respectively. The hardness of the nucleus was measured with a lens guillotine designed by us. Regression analysis was applied to the parameters measured and these were compared with the colour and age. The parameters measured had the following relationship: Colour vs hardness (r value = 0.7569 (p < 0.001 Colour vs diameter (r value = 0.3962 (p < 0.001 Colour vs central thickness (r value = 0.4785 (p < 0.001 Age vs hardness (r value = -0.0499 (p > 0.05 Age vs diameter (r value = 0.0987 (p > 0.05 Age vs central thickness (r value = 0.1700 (p > 0.05 The values showed that colour had a statistically significant relationship with all the 3 parameters (p < 0.001, while age had no significant relationship with the same parameters. The results indicated that colour can be used more reliably to predict physical characteristics of the cataractous lens nucleus, the preoperative knowledge of which would help the surgeon in planning small-incision surgery including phacoemulsification.

  6. Kinetics of central macular thickness reduction in patients with macular edema after intravitreal drug therapy

    OpenAIRE

    He, Lingmin

    2011-01-01

    Lingmin He, Annie Chan, Theodore Leng, Mark S BlumenkranzDepartment of Ophthalmology, Stanford University School of Medicine, Stanford, California, USABackground: The purpose of this study was to characterize central macular thickness and retinal volume following intravitreal injections using time domain and spectral domain optical coherence tomography (TD-OCT and SD-OCT, respectively).Methods: Nine patients with macular edema secondary to diabetes or retinal vein occlusion treated with intra...

  7. Repeatability of corneal parameters with Pentacam after laser in situ keratomileusis

    Directory of Open Access Journals (Sweden)

    Jain Rajeev

    2007-01-01

    Full Text Available Aim: To investigate the coefficient of repeatability (CR for corneal parameters evaluated with Pentacam after laser in situ keratomileusis (LASIK in myopic eyes. Design and Setting: Prospective, non-interventional, non-comparative study in an institutional setup. Materials and Methods: Forty eyes of 40 consecutive subjects who had undergone LASIK for myopia were assessed with the Scheimpflug system (Pentacam 70700: Oculus, Wetzlar Germany. The mean of five consecutive measurements of all the corneal parameters was recorded and CR was calculated as standard deviation of the difference from the mean of these repeat measurements divided by the mean response. The statistical significance of the CR was calculated for these parameters at 5% significance level. Results: The best CR was observed for the periphery of the anterior corneal curvature (0.18% and the least for the horizontal meridian of the posterior corneal curvature (1.29%. Despite being significantly different ( P < 0.001, both the measurements were highly repeatable in post-LASIK eyes. The central, apical and minimal corneal thickness had a CR of 1%, 0.78% and 0.77% respectively. These were equally repeatable ( P >0.323. The CR of the mean radius of curvature of the anterior cornea (0.29% was significantly better ( P < 0.001 than the posterior corneal curvature (0.57%. Conclusion: The CR for the post-LASIK cornea with Pentacam was the best for the anterior corneal curvature. Significantly, Pentacam has a high degree of repeatability for the posterior corneal curvature, which has a potential for early detection of keratectasia in these eyes. Post-LASIK pachymetry with Pentacam also showed excellent repeatability.

  8. Automatized Patient-Specific Methodology for Numerical Determination of Biomechanical Corneal Response.

    Science.gov (United States)

    Ariza-Gracia, M Á; Zurita, J; Piñero, D P; Calvo, B; Rodríguez-Matas, J F

    2016-05-01

    This work presents a novel methodology for building a three-dimensional patient-specific eyeball model suitable for performing a fully automatic finite element (FE) analysis of the corneal biomechanics. The reconstruction algorithm fits and smooths the patient's corneal surfaces obtained in clinic with corneal topographers and creates an FE mesh for the simulation. The patient's corneal elevation and pachymetry data is kept where available, to account for all corneal geometric features (central corneal thickness-CCT and curvature). Subsequently, an iterative free-stress algorithm including a fiber's pull-back is applied to incorporate the pre-stress field to the model. A convergence analysis of the mesh and a sensitivity analysis of the parameters involved in the numerical response is also addressed to determine the most influential features of the FE model. As a final step, the methodology is applied on the simulation of a general non-commercial non-contact tonometry diagnostic test over a large set of 130 patients-53 healthy, 63 keratoconic (KTC) and 14 post-LASIK surgery eyes. Results show the influence of the CCT, intraocular pressure (IOP) and fibers (87%) on the numerical corneal displacement [Formula: see text] the good agreement of the [Formula: see text] with clinical results, and the importance of considering the corneal pre-stress in the FE analysis. The potential and flexibility of the methodology can help improve understanding of the eye biomechanics, to help to plan surgeries, or to interpret the results of new diagnosis tools (i.e., non-contact tonometers). PMID:26307330

  9. Colour of the nucleus as a marker of nuclear hardness, diameter and central thickness.

    Science.gov (United States)

    Gullapalli, V K; Murthy, P R; Murthy, K R

    1995-12-01

    Hundred and thirty patients, aged above 40 years, with senile cataract were examined. Age and colour were selected as the probable preoperative indicators of nuclear hardness. The lens material collected after manual extracapsular extraction was washed and the nucleus isolated. The diameter and central thickness of the nucleus were measured; the mean diameter and mean central thickness were 7.13 mm +/- 0.76 and 3.05 mm +/- 0.48, respectively. The hardness of the nucleus was measured with a lens guillotine designed by us. Regression analysis was applied to the parameters measured and these were compared with the colour and age. The parameters measured had the following relationship: Colour vs hardness (r value = 0.7569) (p 0.05) Age vs diameter (r value = 0.0987) (p > 0.05) Age vs central thickness (r value = 0.1700) (p > 0.05) The values showed that colour had a statistically significant relationship with all the 3 parameters (p cataractous lens nucleus, the preoperative knowledge of which would help the surgeon in planning small-incision surgery including phacoemulsification. PMID:8655196

  10. Corneal Regeneration by Deep Anterior Lamellar Keratoplasty (DALK Using Decellularized Corneal Matrix.

    Directory of Open Access Journals (Sweden)

    Yoshihide Hashimoto

    Full Text Available The purpose of this study is to demonstrate the feasibility of DALK using a decellularized corneal matrix obtained by HHP methodology. Porcine corneas were hydrostatically pressurized at 980 MPa at 10°C for 10 minutes to destroy the cells, followed by washing with EGM-2 medium to remove the cell debris. The HHP-treated corneas were stained with H-E to assess the efficacy of decellularization. The decellularized corneal matrix of 300 μm thickness and 6.0 mm diameter was transplanted onto a 6.0 mm diameter keratectomy wound. The time course of regeneration on the decellularized corneal matrix was evaluated by haze grading score, fluorescein staining, and immunohistochemistry. H-E staining revealed that no cell nuclei were observed in the decellularized corneal matrix. The decellularized corneal matrices were opaque immediately after transplantation, but became completely transparent after 4 months. Fluorescein staining revealed that initial migration of epithelial cells over the grafts was slow, taking 3 months to completely cover the implant. Histological sections revealed that the implanted decellularized corneal matrix was completely integrated with the receptive rabbit cornea, and keratocytes infiltrated into the decellularized corneal matrix 6 months after transplantation. No inflammatory cells such as macrophages, or neovascularization, were observed during the implantation period. The decellularized corneal matrix improved corneal transparency, and remodelled the graft after being transplanted, demonstrating that the matrix obtained by HHP was a useful graft for corneal tissue regeneration.

  11. On the correlation between minimum thickness and central deflection during small punch test

    Science.gov (United States)

    Kumar, Pradeep; Chattopadhyay, J.; Dutta, B. K.

    2016-07-01

    Present paper deals with a detailed study on the correlation between minimum thickness (t/t0) and central deflection (δ/t0). Such data are obtained during the deformation of a small punch test of miniaturized specimen. Finite element studies have been carried out to investigate the effect of various parameters which are expected to influence this correlation. The parameters under consideration are material hardening, material yield stress, coefficient of friction and initial thickness of the specimen. It is shown that the correlation remains unaffected with respect to change in material parameters. Similarly, the coefficient of friction beyond 0.2 also does not affect the correlation. However, change in thickness has significant effect on the correlation. A modification has been suggested in the existing correlation to consider the influence of thickness change. The modified correlation is then used to calculate fracture toughness using the experimental results quoted in the literature. It is shown that the modified correlation improves the fracture toughness prediction considerably.

  12. Corneal laceration caused by river crab

    Directory of Open Access Journals (Sweden)

    Vinuthinee N

    2015-01-01

    Full Text Available Naidu Vinuthinee,1,2 Anuar Azreen-Redzal,1 Jaafar Juanarita,1 Embong Zunaina2 1Department of Ophthalmology, Hospital Sultanah Bahiyah, Alor Setar, 2Department of Ophthalmology, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Malaysia Abstract: A 5-year-old boy presented with right eye pain associated with tearing and photophobia of 1-day duration. He gave a history of playing with a river crab when suddenly the crab clamped his fingers. He attempted to fling the crab off, but the crab flew and hit his right eye. Ocular examination revealed a right eye corneal ulcer with clumps of fibrin located beneath the corneal ulcer and 1.6 mm level of hypopyon. At presentation, the Seidel test was negative, with a deep anterior chamber. Culture from the corneal scrapping specimen grew Citrobacter diversus and Proteus vulgaris, and the boy was treated with topical gentamicin and ceftazidime eyedrops. Fibrin clumps beneath the corneal ulcer subsequently dislodged, and revealed a full-thickness corneal laceration wound with a positive Seidel test and shallow anterior chamber. The patient underwent emergency corneal toileting and suturing. Postoperatively, he was treated with oral ciprofloxacin 250 mg 12-hourly for 1 week, topical gentamicin, ceftazidime, and dexamethasone eyedrops for 4 weeks. Right eye vision improved to 6/9 and 6/6 with pinhole at the 2-week follow-up following corneal suture removal. Keywords: corneal ulcer, pediatric trauma, ocular injury

  13. [Aesthesiometry of the cornea after refractive corneal surgery].

    Science.gov (United States)

    Kohlhaas, M; Draeger, J; Böhm, A; Lombardi, M; Abbondanza, M; Zuppardo, M; Görne, M

    1992-10-01

    The corneal sensibility was examined with the aesthesiometer of Draeger in 41 patients after refractive corneal surgery, 31 patients after radial keratotomy, 5 after epikeratophakia, 5 after excimer laser ablation. It could be shown that after radial corneal incisions the sensibility remains normal. After epikeratophakia the corneal sensibility is asensible even 3 years after operation. The lenticle periphery shows an increase of sensibility after 6 months. Excimer patients with "haze" showed a significant hyposensibility in the centre. The central sensibility showed normal values after a normal corneal wound healing. PMID:1453657

  14. Riboflavin for corneal cross-linking.

    Science.gov (United States)

    O'Brart, D P S

    2016-06-01

    Corneal collagen cross-linking (CXL) with riboflavin and ultraviolet A (UVA) radiation is the first therapeutic modality that appears to arrest the progression of keratoconus and other corneal ectasias. Riboflavin is central to the process, acting as a photosensitizer for the production of oxygen singlets and riboflavin triplets. These free radicals drive the CXL process within the proteins of the corneal stroma, altering its biomechanical properties. Riboflavin also absorbs the majority of the UVA radiation, which is potentially cytotoxic and mutagenic, within the anterior stroma, preventing damage to internal ocular structures, such as the corneal endothelium, lens and retina. Clinical studies report cessation of ectatic progression in over 90% of cases and the majority document significant improvements in visual, keratometric and topographic parameters. Clinical follow-up is limited to 5-10 years, but suggests sustained stability and enhancement in corneal shape. Sight-threatening complications are rare. The optimal stromal riboflavin dosage for CXL is as yet undetermined. PMID:27458610

  15. Overnight corneal swelling with high and low powered silicone hydrogel lenses☆

    Science.gov (United States)

    Moezzi, Amir M.; Fonn, Desmond; Varikooty, Jalaiah; Simpson, Trefford L.

    2014-01-01

    Purpose To compare central corneal swelling after eight hours of sleep in eyes wearing four different silicone hydrogel lenses with three different powers. Methods Twenty-nine neophyte subjects wore lotrafilcon A (Dk, 140), balafilcon A (Dk, 91), galyfilcon A (Dk, 60) and senofilcon A (Dk, 103) lenses in powers −3.00, −10.00 and +6.00 D on separate nights, in random order, and on one eye only. The contra-lateral eye (no lens) served as the control. Central corneal thickness was measured using a digital optical pachometer before lens insertion and immediately after lens removal on waking. Results For the +6.00 D and −10.00 D, lotrafilcon A induced the least swelling and galyfilcon A the most. The +6.00 D power, averaged across lens materials, induced significantly greater central swelling than the −10.00 and −3.00 D (Re-ANOVA, p < 0.001), (7.7 ± 2.9% vs. 6.8 ± 2.8% and 6.5 ± 2.5% respectively) but there was no difference between −10.00 and −3.00 D. Averaged for power, lotrafilcon A induced the least (6.2 ± 2.8%) and galyfilcon A the most (7.6 ± 3.0%) swelling at the center (Re-ANOVA, p < 0.001). Central corneal swelling with +6.00 D was significantly greater than −10.00 D lens power despite similar levels of average lens transmissibility of these two lens powers. Conclusions The differences in corneal swelling of the lens wearing eyes are consistent with the differences in oxygen transmission of the silicone hydrogel lenses. In silicone hydrogel lenses central corneal swelling is mainly driven by central lens oxygen transmissibility. PMID:25649637

  16. Contours of Corcoran Clay Thickness in feet by Page (1986) for the Central Valley Hydrologic Model (CVHM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset defines the thickness of the Corcoran Clay Member of the Tulare Formation. The complex hydrologic system of the Central Valley is simulated...

  17. Evaluation of corneal biomechanical properties following penetrating keratoplasty using ocular response analyzer

    Directory of Open Access Journals (Sweden)

    Vanathi Murugesan

    2014-01-01

    Full Text Available Purpose: To evaluate corneal biomechanical properties in eyes that has undergone penetrating keratoplasty (PK. Materials and Methods: Retrospective observational study in a tertiary care centre. Data recorded included ocular response analyzer (ORA values of normal and post-keratoplasty eyes [corneal hysteresis (CH, corneal resistance factor (CRF, Goldmann-correlated intraocular pressure (IOPg, and cornea-compensated intraocular pressure (IOPcc], corneal topography, and central corneal thickness (CCT. Wilcoxon signed rank test was used to analyze the difference in ORA parameter between post-PK eyes and normal eyes. Correlation between parameters was evaluated with Spearman′s rho correlation. Results: The ORA study of 100 eyes of 50 normal subjects and 54 post-keratoplasty eyes of 51 patients showed CH of 8.340 ± 1.85 and 9.923 ± 1.558, CRF of 8.846 ± 2.39 and 9.577 ± 1.631 in post-PK eyes and normal eyes, respectively. CH and CRF did not correlate with post-keratoplasty astigmatism (P = 0.311 and 0.276, respectively while a significant correlation was observed with IOPg (P = 0.004 and IOPcc (P < 0.001. Conclusion: Biomechanical profiles were significantly decreased in post-keratoplasty eyes with significant correlation with higher IOP as compared with that in normal eyes.

  18. Effect of corneal hydration on the quality of the femtosecond laser anterior lamellar cut.

    Directory of Open Access Journals (Sweden)

    Ossama Nada

    Full Text Available The goal of this study was to assess the effect of corneal hydration on the quality of the femtosecond laser (FSL anterior lamellar cut. The Visumax FSL was used to dissect an 8-mm-diameter corneal flap in 22 eye bank corneas showing various levels of hydration. The intended ablation depth was 220 µm in all eyes, which corresponded to the maximal depth available with this laser. After the cut, the achieved ablation depth was measured using optical coherence tomography images, flap separability was assessed by measuring the mean force generated to detach the flap, and stromal bed roughness was assessed by measuring the Haralick contrast level on the 1000× scanning electron microscopy images of the ablated surfaces. The preoperative central corneal thickness ranged from 547 to 1104 µm (mean ± SEM: 833 ± 30 µm. A negative correlation was found between the level of corneal hydration and the ablation depth measured in the mid-peripheral cornea (r =  -0.626, p = 0.003, the ablation being more superficial in more edematous corneas. The Haralick contrast also tended to increase as a function of corneal hydration (r = 0.416, p = 0.061, suggesting that laser ablation in edematous corneas results in rougher stromal surfaces. These results support the hypothesis that the quality of the FSL lamellar cut decreases as the level of corneal hydration increases. Although FSL is still considered in the field as the tool of the future for corneal dissection, a better understanding of the limits of this tool will be needed before it can replace manual or automated stromal dissection techniques in hydrated corneas.

  19. Three-dimensional LASIK flap thickness variability: topographic central, paracentral and peripheral assessment, in flaps created by a mechanical microkeratome (M2 and two different femtosecond lasers (FS60 and FS200

    Directory of Open Access Journals (Sweden)

    Kanellopoulos AJ

    2013-04-01

    Full Text Available A John Kanellopoulos,1,2 George Asimellis1 1Laservision.gr Institute, Athens, Greece; 2NYU Medical School, New York, USA Purpose: To evaluate programmed versus achieved laser-assisted in situ keratomileusis (LASIK flap central thickness and investigate topographic flap thickness variability, as well as the effect of potential epithelial remodeling interference on flap thickness variability. Patients and methods: Flap thickness was investigated in 110 eyes that had had bilateral myopic LASIK several years ago (average 4.5 ± 2.7 years; range 2–7 years. Three age-matched study groups were formed, based on the method of primary flap creation: Group A (flaps made by the Moria Surgical M2 microkeratome [Antony, France], Group B (flaps made by the Abbott Medical Optics IntraLase™ FS60 femtosecond laser [Santa Ana, CA, USA], and Group C (flaps made by the Alcon WaveLight® FS200 femtosecond laser [Fort Worth, TX, USA]. Whole-cornea topographic maps of flap and epithelial thickness were obtained by scanning high-frequency ultrasound biomicroscopy. On each eye, topographic flap and epithelial thickness variability was computed by the standard deviation of thickness corresponding to 21 equally spaced points over the entire corneal area imaged. Results: The average central flap thickness for each group was 138.33 ± 12.38 µm (mean ± standard deviation in Group A, 128.46 ± 5.72 µm in Group B, and 122.00 ± 5.64 µm in Group C. Topographic flap thickness variability was 9.73 ± 4.93 µm for Group A, 8.48 ± 4.23 µm for Group B, and 4.84 ± 1.88 µm for Group C. The smaller topographic flap thickness variability of Group C (FS200 was statistically significant compared with that of Group A (M2 (P = 0.004, indicating improved topographic flap thickness consistency – that is, improved precision – over the entire flap area affected. Conclusions: The two femtosecond lasers produced a smaller flap thickness and reduced variability than the mechanical

  20. Clinical Observation of Transepithelial Corneal Collagen Cross-linking by Iontophoresis of Riboflavin in Treatment of Keratoconus

    Institute of Scientific and Technical Information of China (English)

    Na Li; Zhengjun Fan; Xiujun Peng; Xu Pang; Chunyu Tian

    2014-01-01

    Purpose: To evaluate the efficacy and safety of transepithelial collagen cross-linking by iontophoretic delivery of riboflavin in treatment of progressive keratoconus.Methods:.Eleven patients (15 eyes) with progressive kerato-conus were enrolled. After 0.1% riboflavin-distilled water so-lution was deliveried via transepithelial iontophpresis for 5 min with 1 mA current, and ultraviolet radiation (370 nm,.3 mW /cm2) was performed at a 1.5 cm distance for 30 min. The fol-low up were 6 months in all eyes. The uncorrected visual acu-ity, corrected visual acuity,endothelial cell counting, corneal thickness,.intraocular pressure, corneal curvature, corneal to-pography,.OCT and corneal opacity before and 6-month after surgery were analyzed.Results: At 6 month postoperatively, mean uncorrected visual acuity and corrected visual acuity changed from 0.36 to 0.30 and from 0.42 to 0.57 without statistical significance..The mean value of each index of corneal curvature declined with-out statistical significance.Kmax value dereased from 60.91 to 59.91, and the astigmatism declined from 3.86 to 3.19. Cen-tral corneal thickness decreased from 460.93 μm to 455.40μm,.and thinnest corneal thickness declined from 450.87 μm to 440.60 μm with no statistical significance..Intraocular pres-sure was significantly elevated from 10.85 mmHg to 12.62 mmHg. Endothelial cell count did not change significantly. No corneal haze occurred. Mean depth of corneal demarcation line was 288.46 μm at 1 month postoperatively..Conclusion:.Transepithelial corneal collagen cross-linking by iontophoresis is effective and safe in the treatment of progres-sive keratoconus, and yields stable clinical outcomes during 6-month follow up..However,.long-term follow up is urgently required. (Eye Science 2014; 29:160-164)

  1. Thickness of Knox Group overburden on Central Chestnut Ridge, Oak Ridge Reservation

    International Nuclear Information System (INIS)

    The thickness of residual soil overlying the Knox Group along Central Chestnut Ridge was estimated by a conventional seismic refraction survey. The purpose of this survey was to identify sites on the Department of Energy's Oak Ridge Reservation where ample overburden exists above the water table for the shallow land burial of low-level radioactive waste. The results of the survey suggest that the upper slopes of the higher ridges in the area have a minimum of 16 to 26 m (52 to 85 ft) of overburden and that the crests of these ridges may have more than 30 m (100 ft). Therefore, it is unlikely that sound bedrock would be encountered during trench excavation [maximum of 10 m (32 ft)] along Central Chestnut Ridge. Also, the relatively low seismic wave velocities measured in the overburden suggest that the water table is generally deep. On the basis of these preliminary results, Central Chestnut Ridge appears to be suitable for further site characterization for the shallow land burial of low-level radioactive waste. 3 references, 5 figures, 1 table

  2. The thick-bedded tail of turbidite thickness distribution as a proxy for flow confinement: Examples from tertiary basins of central and northern Apennines (Italy)

    Science.gov (United States)

    Marini, Mattia; Felletti, Fabrizio; Milli, Salvatore; Patacci, Marco

    2016-07-01

    This study reviews the thickness statistics of non-channelized turbidites from four tertiary basins of Central-Northern Apennines (Italy), where bed geometry and sedimentary character have been previously assessed. Though very different in terms of size and, arguably, character of feeder system, these basins share a common stratigraphic evolution consisting in transition from an early ponded to a late unconfined setting of deposition. Based on comparison of thickness subsets from diverse locations and stratigraphic heights within the studied turbidite fills, this paper seeks to answer the following questions: i) how data collection procedures and field operational constraints (e.g. measure location, outcrop quality, use of thicknesses data from single vs. multiple correlative sections, stratigraphic thickness of the study interval) can affect statistics of sample data? ii) how depositional controls of confined vs. unconfined turbidite basins can result in different thickness-frequency distributions?; and iii) is there in thickness statistics a 'flow confinement' signature which can be used to distinguish between confined and unconfined turbidites? Results suggest that: i) best practices of data collection are crucial to a meaningful interpretation of sample data statistics, especially in presence of stratigraphic and spatial trends of turbidite bed thickness; ii) a systematic bias against cm-thick Tcd Bouma sequence turbidites exists in sample data, which can result in the low-end tail of empirical thickness-frequency distributions to depart significantly from the actual distribution of turbidite thickness; and iii) thickness statistics of beds starting with a basal Ta/Tb Bouma division bear a coherent relationship to the transition from ponded to unconfined depositional settings, consisting in reduction of variance and mean and, consequently, parameters, or even type, of best fit model distribution. This research highlights the role of flow stripping, sediment by

  3. Comparative analysis of corneal morphological changes after transversal and torsional phacoemulsification through 2.2 mm corneal incision

    Directory of Open Access Journals (Sweden)

    Assaf A

    2013-01-01

    Full Text Available Ahmed Assaf, Maged Maher RoshdyOphthalmology Department, Ain Shams University, Cairo, EgyptPurpose: This paper compares and evaluates the corneal morphological changes occurring after cataract surgery through a 2.2 mm corneal incision. We use two platforms for comparison and evaluation, transversal and torsional phacoemulsification.Patients and methods: This study includes 139 consecutive cataractous eyes (nuclear color 2–4, according to the Lens Opacities Classification System III [LOCSIII] of 82 patients undergoing cataract surgery through a 2.2 mm corneal incision. Two different phacoemulsification platforms were used and assigned randomly: we used the WhiteStar Signature® system with the Ellips™ FX transversal continuous ultrasound (US mode for group I (mean age: 65.33 ± 6.97 years, and we used the Infiniti® system with the OZil® Intelligent Phaco (IP torsional US mode for group II (mean age: 64.02 ± 7.55 years. The corneal endothelium and pachymetry were evaluated preoperatively and at 1 month postoperatively. Incision size changes were also evaluated.Results: All surgeries were uneventful. Before intraocular lens implantation, the mean incision size was 2.24 ± 0.06 mm in both groups (P = 0.75. In terms of corneal endothelial cell density, neither preoperative (I vs II: 2304.1 ± 122.5 cell/mm2 vs 2315.6 ± 83.1 cell/mm2, P = 0.80 nor postoperative (I vs II: 2264.1 ± 124.3 cell/mm2 vs 2270.3 ± 89.9 cell/mm2, P = 0.98 differences between the groups were statistically significant. The mean endothelial cell density loss was 1.7% ± 1.6% and 2.0% ± 1.4% in groups I and II, respectively. Furthermore, no significant differences between groups I and II were found preoperatively (P = 0.40 and postoperatively (P = 0.68 in central pachymetry. With surgery, the mean increase in central pachymetry was 28.1 ± 23.6 µm and 24.0 ± 24.0 µm in groups I and II, respectively (P = 0.1.Conclusion: Ellips™ FX transversal and OZil® IP torsional

  4. Groundwater flow functioning in arid zones with thick volcanic aquifer units: North-Central Mexico

    International Nuclear Information System (INIS)

    Population increase in arid zones of Mexico has created the presence of 450% new cities with more that 50,000 inhabitants, as related to the 1950s. Due to the arid nature of the environment, the once sufficient spring and shallow water are becoming inadequate for the supply of those cities. An answer to this problem lies with the sustainable development of deep groundwater. The geological features of the country include fractured volcanic aquifer units that are more than 1,500 m thick, and are regionally continuous over of several hundred thousands of square kilometres. Groundwater development decisions need to consider, in the long span, inter-basin groundwater flow and the need to prevent environmental impacts in distant sites hydraulically connected with extraction centres. Radiocarbon is an excellent tool that initially has been applied to characterize groundwater in thick aquifer units in central Mexico to provide evidence on the hierarchy of flow (local/regional) and water age from where the distance of regional recharge was inferred. Radiocarbon also helps constrain flow path length which can then be used to characterize inter-basin groundwater communication. Radiocarbon has a large potential for future expansion of research and water management application. (author)

  5. Thickness variation of Simpson group in south-central Oklahoma and its tectonic significance

    Energy Technology Data Exchange (ETDEWEB)

    Islam, Q.T.; Crump, J. (ARCO Oil and Gas Co., Plano, TX (USA))

    1989-08-01

    The Middle Ordovician Simpson Group in the Southern Oklahoma aulacogen is composed of interbedded sandstone, limestone, and shale. Several pulses of subsidence controlled the deposition of these sediments. Simpson Group thickness variations, based on an isopach map and corresponding regional cross sections, define the presence of two distinct depositional basins flanked on their northern sides by a stable cratonic shelf. The anomalous thickness of Simpson sediments within these basins is related to syndepositional subsidence along zones of weakness initiated during the rifting stage of aulacogen development. The larger basin covers the western part of south-central Oklahoma. The northern flank of this basin illustrates a zone of rapid thickening of sediments. The updip portion of the northern flank is the northernmost limit of the Southern Oklahoma aulacogen. The depocenter of the larger basin is positioned in the Ardmore basin. Paleostress studies using calcite twin lamellae along the southeastern portion of the Sulfur fault within the smaller basin reveal an east-west compression followed by north-south compression. Surface folds formed by the east-west compression are highly faulted and overturned, whereas the folds formed by the north-south compression are open, slightly asymmetric, with rounded hinges and limbs. Similar east-west-trending structures in the subsurface could be a favorable target for hydrocarbon exploration. In general, these basins are genetically related but are separated by a large Precambrian basement block (Tishomingo Granite).

  6. A brief history of corneal transplantation: From ancient to modern

    Directory of Open Access Journals (Sweden)

    Alexandra X Crawford

    2013-01-01

    corticosteroids. Recent developments, including the replacement of selected corneal layers rather than full-thickness keratoplasty, have the potential to improve or transform corneal transplant surgery in the future.

  7. Corneal melanosis successfully treated using topical mitomycin-C and alcohol corneal epitheliectomy: a 3-year follow-up case report

    Directory of Open Access Journals (Sweden)

    Mehmet Balcı

    2015-08-01

    Full Text Available ABSTRACTWe report a case of primary acquired corneal melanosis without atypia associated with corneal haze in a patient with a history of limbal malignant melanoma and the effect of mitomycin-C. A 75-year-old woman with a history of limbal malignant melanoma presented with loss of vision in right eye. Corneal examination showed a patchy melanotic pigmentation with a central haze. Topical mitomycin-C improved visual acuity and corneal haze. However, the pigmented lesions persisted, and they were removed with alcohol corneal epitheliectomy. Histopathological examination demonstrated primary acquired melanosis without atypia. The lesions were successfully removed, and there were no recurrences during the follow-up period of 36 months. The association of conjunctival and corneal melanosis without atypia is a rare condition. In addition, co-existence of central corneal haze and melanosis may decrease visual acuity. Topical mitomycin-C and alcohol corneal epitheliectomy can be useful treatments in this condition.

  8. Knockdown of NBCe1 In Vivo Compromises the Corneal Endothelial Pump

    OpenAIRE

    Liu, Cailing; Cheng, Qiang; Nguyen, Tracy; Bonanno, Joseph A

    2010-01-01

    Sodium bicarbonate cotransporter (NBC) expression was reduced in corneal endothelium by lentiviral delivery of shRNA. Corneal thickness in these eyes showed greater sensitivity to the topical carbonic anhydrase inhibitor brinzolamide, indicating that NBC works in conjunction with carbonic anhydrases as a component of the corneal endothelial pump.

  9. Corneal thickness and daily curve of intraocular pressure in suspected and glaucomatous patients Espessura corneana e curva diária de pressão intra-ocular em pacientes suspeitos e glaucomatosos

    Directory of Open Access Journals (Sweden)

    Sebastião Cronemberger

    2005-04-01

    Full Text Available PURPOSE: To evaluate in suspected and glaucomatous patients the correlation between central corneal thickness (CCT and intraocular pressure (IOP, measured during the daily curve of intraocular pressure (DCPo, including CCT and IOP measurements in bed at 6 am. The ocular axial length was also compared. METHODS: 114 eyes from 73 patients, 30 eyes suspected of glaucoma (group I and 84 eyes with chronic open-angle glaucoma (group II were prospectively studied. Both groups were subjected to DCPo with measurements of IOP at 9 am, 12 pm, 6 pm, 10:30 pm and on the next day at 6 am in bed and in darkness before the patient gets up. Using the ultrasonic DGH 5100® device, CCT measurements were performed at 9 am, 6 pm, 10:30 pm and the next day at 6 am in bed before the patient gets up. The ocular axial length was also measured. RESULTS: In the total sample and, separately in each group, the mean IOP was more elevated in bed at 6 am. There were no significant CCT changes during the day within each group or between both groups. No statistically significant difference was found between the mean ocular axial length of both groups. CONCLUSIONS: In suspected and glaucomatous patients, there were no statistically significant CCT variations during the day; therefore, only one CCT measurement is sufficient. Also, there was no statistically significant difference between ocular axial length of both groups.OBJETIVO: Verificar em pacientes suspeitos de glaucoma e glaucomatosos se existe correlação entre a espessura corneana central (ECC e a pressão intra-ocular (Po, medidos durante a curva diária de pressão intra-ocular (CDPo, incluindo-se as medidas da ECC e da Po às 6:00 horas da manhã no leito. Avaliar também comparativamente o diâmetro axial ântero-posterior (Diâm. axial em ambos os grupos. MÉTODOS: 114 olhos de 73 pacientes selecionados no Serviço de Glaucoma do Hospital São Geraldo, foram divididos em dois grupos: grupo I - pacientes suspeitos de

  10. The effect of anterior chamber depth on endothelial cell count and postoperative corneal edema in phacoemulsification surgery

    Directory of Open Access Journals (Sweden)

    Ekrem Kadıoğlu

    2011-06-01

    Full Text Available To investigate the effect of anterior chamber depth on corneal endothelial cell loss and development of postoperative corneal edema in patients undergoing phacoemulsification surgery.Materials and methods: The effect of preoperative anterior chamber depth was evaluated by ultrasound biometry of 35 eyes with senile cataract and treated with phacoemulsification on intraoperative endothelial cell loss and at postoperative central corneal thicknesses by specular microscopy.Results: The mean age was 64.8 ± 10.7 years (range 42-84. Preoperative anterior chamber depth, cell density and central corneal thickness were 3.37 ± 0.51 mm (1.61-4.33 mm, 2345 ± 341 cell/mm² (1600-2915 cell/mm² and 536 ± 32 μ (457-588 μ respectively. Postoperative endothelial cell densities were detected 1876 ± 443 cell/mm², 1882 ± 457 cell/mm² and 1920 ± 456 cell/mm² at first week, first month and at third month respectively. Compared to preoperative values, decreases of endothelial cell densities at postoperative first week, first month and third month were found to be significant (p0.05.Conclusion: Phacoemulsification surgery leaded to more endothelial cell loss than expected in patients with shallow anterior chamber. Anterior chamber depth should preoperatively be evaluated especially in the elderly and/or patients with endothelial dystrophy.

  11. The Effect of Contact Lens Usage on Corneal Biomechanical Parameters in Keratoconus Patients

    Directory of Open Access Journals (Sweden)

    Ali Bülent Çankaya

    2012-05-01

    Full Text Available Pur po se: To determine and compare the corneal biomechanical properties in keratoconus patients using rigid gas permeable contact lenses and keratoconus patients who do not use contact lenses. Ma te ri al and Met hod: The study consisted of 70 healthy controls (Group A, 27 ketatoconus subjects who do not use contact lens (Group B and 36 rigid gas permeable contact lens using keratoconic patients (Group C. Corneal viscoelastic parameters were measured with an Ocular response analyzer (ORA. Central corneal thickness was measured with an ultrasonic pachymeter. The differences in ORA parameters between the groups were compared. Re sults: The mean corneal hysteresis (CH in Groups A, B, and C were 10.3±1.5 mm Hg, 7.8±1.4 mm Hg, and 7.4±1.2 mm Hg, respectively. The differences in mean CH between Group A and the other two groups were statistically significant (p<0.01 for both comparisons, but no statistically significant difference was found between groups B and C in terms of mean CH (p=0.61. The mean corneal resistance factor (CRF was 10.7±1.9 in Group A compared with 6.6±1.6 in Group B and 6.1±1.5 in Group C. The differences in mean CRF between Group A and the other two groups were statistically significant (p<0.01 for both comparisons. There was no significant difference in CRF between the keratoconus eyes with or without rigid gas permeable contact lens usage (p=0.57. Dis cus si on: Our results suggest that ORA-generated parameters may be different in subjects with keratoconus. Corneal biomechanical parameters did not demonstrate a clear trend of change with rigid gas permeable contact lens usage. (Turk J Ophthalmol 2012; 42: 197-201

  12. Effect of Orbital Decompression on Corneal Topography in Patients with Thyroid Ophthalmopathy.

    Directory of Open Access Journals (Sweden)

    Su Ah Kim

    Full Text Available To evaluate changes in corneal astigmatism in patients undergoing orbital decompression surgery.This retrospective, non randomized comparative study involved 42 eyes from 21 patients with thyroid ophthalmopathy who underwent orbital decompression surgery between September 2011 and September 2014. The 42 eyes were divided into three groups: control (9 eyes, two-wall decompression (25 eyes, and three-wall decompression (8 eyes. The control group was defined as the contralateral eyes of nine patients who underwent orbital decompression surgery in only one eye. Corneal topography (Orbscan II, Hertel exophthalmometry, and intraocular pressure were measured at 1 month before and 3 months after surgery. Corneal topographic parameters analyzed were total astigmatism (TA, steepest axis (SA, central corneal thickness (CCT, and anterior chamber depth (ACD.Exophthalmometry values and intraocular pressure decreased significantly after the decompression surgery. The change (absolute value (|x| of the difference in astigmatism at the 3 mm zone was significantly different between the decompression group and the controls (p = 0.025. There was also a significant change in the steepest axis at the 3 mm zone between the decompression group and the controls (p = 0.033. An analysis of relevant changes in astigmatism showed that there was a dominant tendency for incyclotorsion of the steepest axis in eyes that underwent decompression surgery. Using Astig PLOT, the mean surgically induced astigmatism (SIA was 0.21±0.88 D with an axis of 46±22°, suggesting that decompression surgery did change the corneal shape and induced incyclotorsion of the steepest axis.There was a significant change in corneal astigmatism after orbital decompression surgery and this change was sufficient to affect the optical function of the cornea. Surgeons and patients should be aware of these changes.

  13. The Continental Distillery: Building Thick Continental Crust in the Central Andes (Invited)

    Science.gov (United States)

    Wagner, L. S.; Beck, S. L.; Zandt, G.; Long, M. D.; Tavera, H.; Minaya, E.; Biryol, C. B.; Bishop, B.; Eakin, C. M.; Franca, G.; Knezevic Antonijevic, S.; Kumar, A.; Ryan, J. C.; Scire, A. C.; Ward, K. M.; Young, B. E.

    2013-12-01

    The formation of stable continental crust and the associated development and destruction of mantle lithospheric roots is central to our understanding of plate tectonics, both at its inception and as an ongoing process today. Subduction zones play an important role in the creation and refinement of continental crust, and also serve as a possible mechanism for the removal of residual mantle material. The central Andes provide an intriguing laboratory for the study of these processes. Up to 400 km wide, 1500 km long, and with an average elevation of 4 km, the Altiplano Plateau is the largest orogen on earth associated with an ocean-continent subduction zone. This is much larger than adjacent 'normal' sections of the Andes, raising the question of why this portion of South American crust became so much more substantial than surrounding areas. Over the past several years, new seismic data have made it possible for us to develop a more complete picture of the lithospheric and asthenospheric processes involved in the development of the Altiplano Plateau and the adjacent narrower orogen further to the north. The 'Central Andean Uplift and the Geodynamics of High Topography' (CAUGHT) comprises in part a broadband deployment of 50 stations across the northern flank of the Altiplano Plateau in southern Peru and northern Bolivia. The adjacent 'PerU Lithosphere and Slab Experiment' (PULSE) includes 40 broadband stations that cover the region directly north of the CAUGHT deployment, encompassing the northern edge of the Altiplano, the transition to 'normal' width orogen, and the transition in slab geometry from normal to flat from south to north across the study area. Uplift of the Altiplano Plateau is likely due to some combination shortening, isostasy due to lithospheric destruction or changes in crustal density, magmatic addition to the crust, and/or flow within the thickened crust. Our studies indicate pervasive low velocities across the Altiplano consistent with a

  14. Ocular histopathological changes after eyeball enucleation induced by corneal trauma

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To observe the ocular histopathological changes aftereyeball enucleation induced by corneal trauma.Methods: Light microscopic examination was done on 117 eyeball specimens enucleated after corneal trauma (18 with corneal fissure and 99 with corneal perforating trauma).Results: Acute, subacute or chronic inflammatory changes, and fibrous membrane formation were observed in well-closed corneal wounds, whereas inflammation, atrophy and scar were observed in the focal tissues. But at the late period, secondary glaucoma, retinal detachment, endophthalmitis and eyeball atrophy resulted in blindness. Corneal fistula was observed in those with inadequate cure of wounds caused by ingrowth of corneal epithelium, embedment of iris and vitreous body, and large area of centrally located tissue deficiency of the corneal. A high incidence of endophthalmitis was noted due to the presence of corneal fistula. Severe inflammation was observed in the anterior segmental tissues with fibrous infiltration in the anterior chamber, which might result in rapid destruction of the eyeballs.Conclusions: Ocular pathology varies with the difference of the position, form, size and closing conditions of the corneal laceration after trauma.

  15. Goldmann applanation tonometry compared with corneal-compensated intraocular pressure in the evaluation of primary open-angle Glaucoma

    Directory of Open Access Journals (Sweden)

    Ehrlich Joshua R

    2012-09-01

    Full Text Available Abstract Background To better understand the role of corneal properties and intraocular pressure (IOP in the evaluation of primary open-angle glaucoma (POAG; and to determine the feasibility of identifying glaucomatous optic neuropathy (GON using IOP corrected and uncorrected for corneal biomechanics. Methods Records from 1,875 eyes of consecutively evaluated new patients were reviewed. Eyes were excluded if central corneal thickness (CCT or Ocular Response Analyzer (ORA measurements were unavailable. Presence or absence of GON was determined based on morphology of the optic disc, rim and retinal nerve fiber layer at the time of clinical examination, fundus photography and Heidelberg Retinal Tomography. Goldmann-applanation tonometry (GAT in the untreated state was recorded and Goldmann-correlated (IOPg and corneal-compensated IOP (IOPcc were obtained using the ORA. Glaucomatous eyes were classified as normal or high-tension (NTG, HTG using the conventional cutoff of 21 mm Hg. One eligible eye was randomly selected from each patient for inclusion. Results A total of 357 normal, 155 HTG and 102 NTG eyes were included. Among NTG eyes, IOPcc was greater than GAT (19.8 and 14.4 mm Hg; p  Conclusions IOPcc may account for measurement error induced by corneal biomechanics. Compared to GAT, IOPcc may be a superior test in the evaluation of glaucoma but is unlikely to represent an effective diagnostic test.

  16. SURGICAL OUTCOME OF TRIPLE PROCEDURE AS PENETRATING KERATOPLASTY WITH EXTRACAPSULAR CATARACT EXTRACTION WITH POSTERIOR CHAMBER INTRAOCULAR LENS IMPLANTATION IN PATIENTS WITH BOTH CENTRAL CORNEAL OPACITY AND ADVANCED CATARACT AT RURAL SET UP

    Directory of Open Access Journals (Sweden)

    Shubhangi Nigwekar, Kishor Badhe, Neeta Misra, Surekha Bangal

    2015-10-01

    Full Text Available Purpose: To study the surgical outcome of triple procedure as penetrating keratoplasty (PKP with conventional extra capsular cataract extraction (ECCE with posterior chamber intraocular lens (PCIOL implantation in patients with both central corneal opacity and advanced cataract at rural set up. Introduction: When corneal opacity and cataract present together then well-established and effective triple procedure is indicated. Prognosis for a clear graft is good in triple, as graft endothelium does not touch the hard nucleus which may occur in two steps or sequential surgery. It provides faster visual rehabilitation. Being single step procedure it reduces patient’s hospital stay, postoperative care and follows up visits. Methodology: In this hospital based observational , three years longitudinal study, we studied the surgical outcome of relatively rare one step triple procedure as PKP with conventional ECCE with PCIOL implantation in sulcus or in bag, in patients with both central corneal opacity and advanced cataract at rural set up. The outcome measures included graft clarity on slit lamp, postoperative unaided visual acuity with Snellen’s chart and the occurrence of postoperative complications after taking IEC permission and informed written consent in local language from study patients. Results: Out of 13 study patients mean age was 61.15yrs (Range50-80yrs. Follow up range was 9-34 months. At final follow up 9 patients (69.23% had clear grafts and 61.52% patients gained visual acuity >6/24. Graft failure was the most common post operative complication in 30.76% followed by Posterior capsular opacification (PCO in 15.38% patients which was treated well with YAG laser capsulotomy. Conclusion: Triple procedure gives good results in respect to graft clarity, unaided vision, and faster rehabilitation.

  17. The Long-Term Effects of Silicone Hydrogel Contact Lens Wear on Corneal Morphology

    Directory of Open Access Journals (Sweden)

    Yelda Yıldız

    2012-03-01

    Full Text Available Pur po se: To evaluate the effects of silicone hydrogel contact lenses (SHCL on central corneal thickness (CCT, corneal endothelial cell morphology, and tear functions. Ma te ri al and Met hod: Fifty-five eyes of 28 SHCL wearers (Group 1 and 52 eyes of 26 healthy subjects (Group 2 were included in this study’. According to their contact lens wearing time, the contact lens wearing subjects were divided into 2 groups: Group 1a - wearing time less than 1 year and Group 1b - wearing time more than 1 year. CCT, epithelial thickness, corneal endothelial cell morphology, ocular surface disease index score (OSDI, and tear break-up time (TBUT were evaluated. Re sults: In Group 1 and Group 2, the mean CCT was 561.85±39.98 µm and 537.25±27.12 µm, respectively (p: 0.001.The epithelial thickness was 50.38±5.41 µm and 55.64±5.32 µm, respectively (p: 0.001. In Group 1a and Group1 b, the mean CCT was 573.39±33.86 µm and 546.96±42.98 µm (p: 0.014 and the epithelial thickness was 49.51±4.78 µm and 51.50±6.04 µm (p>0.05, respectively. In Group 1, the percentage of endothelial cells larger than 700µ was low, while the percentage of endothelial cells between 200 and 400µ was high (p<0,05. Dis cus si on: With SHCL wear, the corneal morphology is more affected in the short-term period. During long-term contact lens wear, the cornea enters an adaptation period and shows near-normal morphology. Tear functions are not affected by short- or long-term SHCL wear. (Turk J Ophthalmol 2012; 42: 91-6

  18. Tear Mediators in Corneal Ectatic Disorders

    Science.gov (United States)

    Pásztor, Dorottya; Kolozsvári, Bence Lajos; Csutak, Adrienne; Berta, András; Hassan, Ziad; Ujhelyi, Bernadett; Gogolák, Péter; Fodor, Mariann

    2016-01-01

    Purpose To compare the concentrations of 11 tear mediators in order to reveal the biochemical difference between pellucid marginal degeneration (PMD) and keratoconus (KC). Methods We have designed a cross-sectional study in which patients with corneal ectasia based on slit-lamp biomicroscopy and Pentacam HR (keratometry values (K1, K2, Kmax), astigmatism, minimal radius of curvature (Rmin), corneal thickness (Apex and Min), indices (surface variation, vertical asymmetry, keratoconus, central keratoconus, height asymmetry and decentration)) were enrolled. Eyes of keratoconic patients were similar to the PMD patients in age and severity (K2, Kmax and Rmin). Non-stimulated tear samples were collected from nine eyes of seven PMD patients, 55 eyes of 55 KC patients and 24 eyes of 24 healthy controls. The mediators’ (interleukin -6, -10, chemokine ligand 5, -8, -10, matrix metalloproteinase (MMP) -9, -13, tissue inhibitor of metalloproteinases (TIMP)-1, tissue plasminogen activator, plasminogen activator inhibitor, nerve growth factor) concentrations were measured using Cytometric Bead Array. Results MMP-9 was the only mediator which presented relevant variances between the two patient groups (p = 0.005). The ratios of MMP-9 and TIMP-1 were 2.45, 0.40 and 0.23 in PMD, KC and the controls, respectively. Conclusion As far as we are aware, this is the first study that aims to reveal the biochemical differences between PMD and KC. Further studies of biomarkers to investigate the precise role of these mediators need to be defined, and it is important to confirm the observed changes in a larger study to gain further insights into the molecular alterations in PMD. PMID:27074131

  19. Significance of corneal arcus

    Directory of Open Access Journals (Sweden)

    K Mohan Raj

    2015-01-01

    Full Text Available The corneal arcus consists of cholesterol, phospholipids and triglycerides. As serum triglyceride is one of the accurate of lipid metabolic state, greater importance was given, and it was found to be elevated in 72% of patients and a positive correlation with increasing age. This suggests a strong correlation between impairment of lipid metabolism and incidence of corneal arcus.

  20. Estimated Thickness of Quaternary Sediment in the Wood River Valley aquifer system, South-Central Idaho

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This dataset is the estimated thickness of Quaternary sediment of the Wood River Valley aquifer system. This isopach map was constructed by subtracting the...

  1. Interannual variability of summer sea ice thickness in the Siberian and central Arctic under different atmospheric circulation regimes

    Science.gov (United States)

    Haas, Christian; Eicken, Hajo

    2001-03-01

    Extensive drill hole and electromagnetic induction measurements of sea ice thickness in the Siberian and central Arctic Seas in the summers of 1993, 1995, and 1996 reveal significant interannual variability. In the Laptev Sea, minimum and maximum modal first-year ice thicknesses amounted to 1.25 and 1.85 m in 1995 and 1996, respectively. Ice thickness correlates with ice extent, which reached a record minimum in August 1995 and was well above average in 1996. These differences are explained by the strength and location of a summer cyclonic atmospheric circulation pattern affecting both ice advection and surface melt. From drifting buoys deployed in 1995 and satellite radar backscatter data, first- and second-year ice regimes are delineated. Differences in first-year ice backscatter coefficients between 1993, 1995, and 1996 are explained by differences in level ice surface roughness. The Lagrangian evolution of ice thickness between 1995 and 1996 is studied. While the shape of the thickness distribution does not change significantly, the mean (modal) ice thickness of the ice field increases from 1.80 m (1.25 m) in 1995 to 2.86 m (2.25 m) in 1996. The thickness distribution of second-year ice in 1996 closely agrees with that of level multiyear ice downstream in the Transpolar Drift obtained in 1991. In 1996, mean level ice thickness increases at 0.23 and 0.16 m deg-1 with latitude in the Kara and Laptev Sea sectors of the Arctic Ocean, respectively.

  2. Comparing bevacizumab and ranibizumab for initial reduction of central macular thickness in patients with retinal vein occlusions

    OpenAIRE

    Singer, Michael

    2013-01-01

    Michael A Singer,1 Steven R Cohen,2 Sylvia L Groth,3 Salman Porbandarwalla21Medical Center Ophthalmology Associates (MCOA), San Antonio, Texas, USA; 2Department of Ophthalmology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA; 3University of Minnesota Medical School, Minneapolis, Minnesota, USAPurpose: To examine short-term effects of ranibizumab versus bevacizumab on reduction of optical coherence tomography (OCT) central macular thickness (CMT) in patients...

  3. Corneal reconstruction by stem cells and bioengineering

    Directory of Open Access Journals (Sweden)

    Arjamaa O

    2012-09-01

    Full Text Available Olli ArjamaaDepartment of Biology, University of Turku, Turku, FinlandAbstract: Almost 300 million people are visually impaired worldwide due to various eye diseases such as cataracts, glaucoma, age-related macular degeneration, diabetic retinopathy, and corneal diseases. Notably, ten million people are blind because of severe ocular surface diseases and the majority of cases occur in developing countries. Blinding ocular surface diseases have, however, become treatable by grafting of surface layers, or by full-thickness transplantation of the cornea. As the demand for human corneal tissue for surface reconstruction and transplantation far exceeds the supply, methods are being developed to supplement tissue donation. Xenotransplantation of the cornea or cells from genetically modified pigs may become one of the solutions. Transplantation of limbal stem cells within tissue biopsies, to restore the transparency of the cornea is another remarkable method, which has shown its potential in several clinical studies. The combination of stem cell technology and engineering of biocompatible tissue equivalent, still at preclinical stage, has shown us how synthetic corneal tissue is able to guide cultured corneal stromal stem cells of human origin, to become native-like stroma, the most important layer of the cornea. These findings give hope for a large-quantity production of biomaterial for corneal reconstruction. As such, clinical ophthalmologists should become more familiar with the methods of laboratory science.Keywords: eye, grafting, keratoplasty, xenotransplantation, cell reservoir, biocompatible tissue equivalent

  4. Comparison of Corneal Endothelial Changes After a Single-Dose Injection of Bevacizumab or Ranibizumab

    Directory of Open Access Journals (Sweden)

    Fatih Horozoğlu

    2013-12-01

    Full Text Available Purpose: To compare the corneal endothelial changes after injection of a single-dose intravitreal bevacizumab or intravitreal ranibizumab. Material and Method: In this retrospective study, we evaluated 27 eyes of 27 patients with either diabetic macular edema or senile macular degeneration, who underwent 1.25 mg/0.05 ml intravitreal bevacizumab or 0.5 mg/0.05 ml ranibizumab injection. None of the patients had corneal pathology. Fourteen eyes of 14 patients received intravitreal ranibizumab, other 13 eyes of 13 patients received intravitreal bevacizumab. We evaluated preoperative and postoperative 1st week and 1st month visual acuity, corneal endothelial count at mm2, intraocular pressure, and pachymetry results. For statistical analysis, Mann-Whitney U and Wilcoxon tests were used. Results: Mean age of the patients was 69.3±12.5 (44-85 year. Average corneal endothelial cell count for bevacizumab and ranibizumab was preoperatively 2358.1±487 and 2348.9±598, postoperative 1. week 2360.8±474.1 and 2398.3±585.6, postoperative 1. month 2315.1±465 and 2407.4±585.6, respectively. Preoperative and postoperative corneal endothelial cell counts were not statistically significantly different in both groups (respectively, 1. week p=0.953 and p=0.59; 1. month p=0.26 and p=0.555. Average central macular thickness for bevacizumab and ranibizumab was preoperatively 527.3±36.9 and 544.1±55.5 µm, postoperative 1. week 529.2±49.9 and 543.5±51.8 µm, postoperative 1. month 530.3±55 and 543.9±46.6 µm, respectively. Preoperative and postoperative central macular thickness values for both groups were not statistically significantly different (respectively, 1. week P=0.515 and P=0.838; 1. month P=0.678 and P=0.444. Discussion: Injection of a single dose of 1.25 mg/0.05 ml bevacizumab or 0.5 mg/0.05 ml ranibizumab does not affect the corneal endothelial cell count at 1. week and 1. month. (Turk J Ophthalmol 2013; 43: 391-4

  5. Corneal blindness and xenotransplantation.

    Science.gov (United States)

    Lamm, Vladimir; Hara, Hidetaka; Mammen, Alex; Dhaliwal, Deepinder; Cooper, David K C

    2014-01-01

    Approximately 39 million people are blind worldwide, with an estimated 285 million visually impaired. The developing world shoulders 90% of the world's blindness, with 80% of causative diseases being preventable or treatable. Blindness has a major detrimental impact on the patient, community, and healthcare spending. Corneal diseases are significant causes of blindness, affecting at least 4 million people worldwide. The prevalence of corneal disease varies between parts of the world. Trachoma, for instance, is the second leading cause of blindness in Africa, after cataracts, but is rarely found today in developed nations. When preventive strategies have failed, corneal transplantation is the most effective treatment for advanced corneal disease. The major surgical techniques for corneal transplantation include penetrating keratoplasty (PK), anterior lamellar keratoplasty, and endothelial keratoplasty (EK). Indications for corneal transplantation vary between countries, with Fuchs' dystrophy being the leading indication in the USA and keratoconus in Australia. With the exception of the USA, where EK will soon overtake PK as the most common surgical procedure, PK is the overwhelming procedure of choice. Success using corneal grafts in developing nations, such as Nepal, demonstrates the feasibility of corneal transplantation on a global scale. The number of suitable corneas from deceased human donors that becomes available will never be sufficient, and so research into various alternatives, for example stem cells, amniotic membrane transplantation, synthetic and biosynthetic corneas, and xenotransplantation, is progressing. While each of these has potential, we suggest that xenotransplantation holds the greatest potential for a corneal replacement. With the increasing availability of genetically engineered pigs, pig corneas may alleviate the global shortage of corneas in the near future. PMID:25268248

  6. Quantitative proteomic analysis of mice corneal tissues reveals angiogenesis-related proteins involved in corneal neovascularization.

    Science.gov (United States)

    Shen, Minqian; Tao, Yimin; Feng, Yifan; Liu, Xing; Yuan, Fei; Zhou, Hu

    2016-07-01

    Corneal neovascularization (CNV) was induced in Balb/c mice by alkali burns in the central area of the cornea with a diameter of 2.5mm. After fourteen days, the cornea from one eye was collected for histological staining for CNV examination, while the cornea from the other eye of the same mouse was harvested for proteomic analysis. The label-free quantitative proteomic approach was applied to analyze five normal corneal tissues (normal group mice n=5) and five corresponding neovascularized corneal tissues (model group mice n=5). A total of 2124 proteins were identified, and 1682 proteins were quantified from these corneal tissues. Among these quantified proteins, 290 proteins were significantly changed between normal and alkali burned corneal tissues. Of these significantly changed proteins, 35 were reported or predicted as angiogenesis-related proteins. Then, these 35 proteins were analyzed using Ingenuity Pathway Analysis Software, resulting in 26 proteins enriched and connected to each other in the protein-protein interaction network, such as Lcn-2, αB-crystallin and Serpinf1 (PEDF). These three significantly changed proteins were selected for further Western blotting validation. Consistent with the quantitative proteomic results, Western blotting showed that Lcn-2 and αB-crystallin were significantly up-regulated in CNV model, while PEDF was down-regulated. This study provided increased understanding of angiogenesis-related proteins involved in corneal vascular development, which will be useful in the ophthalmic clinic of specifically target angiogenesis. PMID:27049463

  7. Validez y reproducibilidad de la ecografía convencional de alta resolución en la estimación del espesor corneal central, profundidad de la cámara anterior y ángulo iridocorneal

    OpenAIRE

    Gómez Herrera, Juan Jesús

    2015-01-01

    En el campo de las técnicas de diagnóstico basadas en imágenes, tanto en atención primaria como especializada, uno de los pilares de la colaboración con el programa de la Organización Mundial de la Salud Visión 2020 es el desarrollo y aplicación de técnicas que evalúen los factores cuya detección y/o corrección permitan prevenir la aparición de glaucoma. Entre estos factores se encuentran la evaluación del ángulo iridocorneal y la estimación tanto del espesor corneal central como de la profun...

  8. Serial thick, frozen, gallocyanin stained sections of human central nervous system

    OpenAIRE

    Heinsen, Helmut; Heinsen, Y. L.

    2010-01-01

    A rapid method for macroscopic and microscopic investigation of human CNS is proposed. After fonnalin fixation, gelatin or agarose embedding, and cryoprotective treatment, frozen human spinal cords, brainstems, or hemispheres can be serially cut into 0.7 mm thick slices. Stained with gallocyanin-chromalum, these slices facilitate cytoarchitectonic, neuropathologic, and quantitative examination. Regions of interest from parallel fonnalin-stored unstained slices can be embedded into paraffin an...

  9. Airborne radar survey above Vostok region, east-central Antarctica: ice thickness and Lake Vostok geometry

    OpenAIRE

    Tabacco, I. E.; Department of Earth Science, University of Milan, Via Cicognara 7, I-20129 Milan, Italy; Bianchi, C.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Zirizzotti, A.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Zuccheretti, E.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Forieri, A.; Department of Earth Science, University of Milan, Via Cicognara 7, I-20129 Milan, Italy; Della Vedova, A.; Department of Earth Science, University of Milan, Via Cicognara 7, I-20129 Milan, Italy

    2002-01-01

    During the 1999-2000 Italian Expedition, an airborne radar survey was performed along 12 transects across Lake Vostok, Antarctica, and its western and eastern margins. Ice thickness, subglacial elevation and the precise location of lake boundaries were determined. Radar data confirm the geometry derived from previous surveys, but with some slight differences. We measured a length of up to 260 km, a maximum width of 81 km and an area of roughly 14000 km2. Along the major axis, from north...

  10. Hypocellular scar formation or aberrant fibrosis induced by an intrastromal corneal ring: a case report

    Directory of Open Access Journals (Sweden)

    Ramkumar Hema L

    2011-08-01

    Full Text Available Abstract Introduction Intrastromal corneal rings or segments are approved for the treatment of myopia and astigmatism associated with keratoconus. We describe a clinicopathological case of intrastromal corneal rings. For the first time, the molecular pathological findings of intrastromal corneal rings in the cornea are illustrated. Case presentation A 47-year-old African-American man with a history of keratoconus and failure in using a Rigid Gas Permeable contact lens received an intrastromal corneal ring implant in his left eye. Due to complications, penetrating keratoplasty was performed. The intrastromal corneal ring channels were surrounded by a dense acellular (channel haze and/or hypocellular (acidophilic densification collagen scar and slightly edematous keratocytes. Mild macrophage infiltration was found near the inner aspect of the intrastromal corneal rings. Molecular analyses of the microdissected cells surrounding the intrastromal corneal ring channels and central corneal stroma revealed 10 times lower relative expression of IP-10/CXCL10 mRNA and two times higher CCL5 mRNA in the cells surrounding the intrastromal corneal ring, as compared to the central corneal stroma. IP-10/CXCL10 is a fibrotic and angiostatic chemokine produced by macrophages, endothelial cells and fibroblasts. Conclusion An intrastromal corneal ring implant can induce hypocellular scar formation and mild inflammation, which may result from aberrant release of fibrosis-related chemokines.

  11. Corneal Segmentation Analysis Increases Glaucoma Diagnostic Ability of Optic Nerve Head Examination, Heidelberg Retina Tomograph's Moorfield's Regression Analysis, and Glaucoma Probability Score.

    Science.gov (United States)

    Saenz-Frances, F; Jañez, L; Berrozpe-Villabona, C; Borrego-Sanz, L; Morales-Fernández, L; Acebal-Montero, A; Mendez-Hernandez, C D; Martinez-de-la-Casa, J M; Santos-Bueso, E; Garcia-Sanchez, J; Garcia-Feijoo, J

    2015-01-01

    Purpose. To study whether a corneal thickness segmentation model, consisting in a central circular zone of 1 mm radius centered at the corneal apex (zone I) and five concentric rings of 1 mm width (moving outwards: zones II to VI), could boost the diagnostic accuracy of Heidelberg Retina Tomograph's (HRT's) MRA and GPS. Material and Methods. Cross-sectional study. 121 healthy volunteers and 125 patients with primary open-angle glaucoma. Six binary multivariate logistic regression models were constructed (MOD-A1, MOD-A2, MOD-B1, MOD-B2, MOD-C1, and MOD-C2). The dependent variable was the presence of glaucoma. In MOD-A1, the predictor was the result (presence of glaucoma) of the analysis of the stereophotography of the optic nerve head (ONH). In MOD-B1 and MOD-C1, the predictor was the result of the MRA and GPS, respectively. In MOD-B2 and MOD-C2, the predictors were the same along with corneal variables: central, overall, and zones I to VI thicknesses. This scheme was reproduced for model MOD-A2 (stereophotography along with corneal variables). Models were compared using the area under the receiver operator characteristic curve (AUC). Results. MOD-A1-AUC: 0.771; MOD-A2-AUC: 0.88; MOD-B1-AUC: 0.736; MOD-B2-AUC: 0.845; MOD-C1-AUC: 0.712; MOD-C2-AUC: 0.838. Conclusion. Corneal thickness variables enhance ONH assessment and HRT's MRA and GPS diagnostic capacity. PMID:26180641

  12. Designing multifocal corneal models to correct presbyopia by laser ablation

    Science.gov (United States)

    Alarcón, Aixa; Anera, Rosario G.; Del Barco, Luis Jiménez; Jiménez, José R.

    2012-01-01

    Two multifocal corneal models and an aspheric model designed to correct presbyopia by corneal photoablation were evaluated. The design of each model was optimized to achieve the best visual quality possible for both near and distance vision. In addition, we evaluated the effect of myosis and pupil decentration on visual quality. The corrected model with the central zone for near vision provides better results since it requires less ablated corneal surface area, permits higher addition values, presents stabler visual quality with pupil-size variations and lower high-order aberrations.

  13. KERATOCONUS AND EPI-OFF CORNEAL CROSS-LINKING BY RIBOFLAVIN-ULTRAVIOLET TYPE A: INDICATIONS AND RATIONAL OF EMPLOYMENT

    Directory of Open Access Journals (Sweden)

    A. Caporossi

    2010-11-01

    Full Text Available Keratoconus is the most common dystrophic corneal ectasia, characterized by the presence of irregular astigmatism associated with a reduction of corneal thickness. It is the leading cause of corneal transplant in Italy and Europe. Recently a new therapeutic opportunity is offered by Riboflavin + UV A Corneal Cross-linking, first introduced in Italy in 2004 by Professor Aldo Caporossi at the Department of Ophthalmology of Siena. This treatment requires early diagnosis to prevent corneal ectatic modifications related to pathology. The modern treatment of keratoconus is directed into three "directories": 1 prevention of its progression; 2 reduction of the related refractive defect and induced corneal aberrations; 3 replacement of ectatic corneal in advanced phase not subjected to conservative approach and HRGP lens intolerance. Riboflavin + UV A Collagen Cross-linking is mostly indicated in patients between 10 and 26 years old with progressive keratoconus (stage 1 and 2 with strict adherence to the recommended inclusion thickness (thinnest point > 400 microns.

  14. Correlating corneal arcus with atherosclerosis in familial hypercholesterolemia

    Directory of Open Access Journals (Sweden)

    Zech Loren A

    2008-03-01

    Full Text Available Abstract Background A relationship between corneal arcus and atherosclerosis has long been suspected but is controversial. The homozygous familial hypercholesterolemia patients in this study present a unique opportunity to assess this issue. They have both advanced atherosclerosis and corneal arcus. Methods This is a cross-sectional study of 17 patients homozygous for familial hypercholesterolemia presenting to the Clinical Center of the National Institutes of Health. Plasma lipoproteins, circumferential extent of arcus, thoracic aorta and coronary calcific atherosclerosis score, and Achilles tendon width were measured at the National Institutes of Health. Results Patients with corneal arcus had higher scores for calcific atherosclerosis (mean 2865 compared to 412, cholesterol-year score (mean 11830 mg-yr/dl compared to 5707 mg-yr/dl, and Achilles tendon width (mean 2.54 cm compared to 1.41 cm than those without. Corneal arcus and Achilles tendon width were strongly correlated and predictive of each other. Although corneal arcus was correlated with calcific atherosclerosis (r = 0.67; p = 0.004, it was not as highly correlated as was the Achilles tendon width (r = 0.855; p Conclusion Corneal arcus reflects widespread tissue lipid deposition and is correlated with both calcific atherosclerosis and xanthomatosis in these patients. Patients with more severe arcus tend to have more severe calcific atherosclerosis. Corneal arcus is not as good an indicator of calcific atherosclerosis as Achilles tendon thickness, but its presence suggests increased atherosclerosis in these hypercholesterolemic patients.

  15. Association of CHRDL1 mutations and variants with X-linked megalocornea, Neuhäuser syndrome and central corneal thickness

    DEFF Research Database (Denmark)

    Davidson, Alice E; Cheong, Sek-Shir; Hysi, Pirro G; Venturini, Cristina; Plagnol, Vincent; Ruddle, Jonathan B; Ali, Hala; Carnt, Nicole; Gardner, Jessica C; Hassan, Hala; Gade, Else; Kearns, Lisa; Jelsig, Anne Marie; Restori, Marie; Webb, Tom R; Laws, David; Cosgrove, Michael; Hertz, Jens M; Russell-Eggitt, Isabelle; Pilz, Daniela T; Hammond, Christopher J; Tuft, Stephen J; Hardcastle, Alison J

    2014-01-01

    We describe novel CHRDL1 mutations in ten families with X-linked megalocornea (MGC1). Our mutation-positive cohort enabled us to establish ultrasonography as a reliable clinical diagnostic tool to distinguish between MGC1 and primary congenital glaucoma (PCG). Megalocornea is also a feature of...

  16. Collagens and proteoglycans of the corneal extracellular matrix

    OpenAIRE

    Michelacci Y.M.

    2003-01-01

    The cornea is a curved and transparent structure that provides the initial focusing of a light image into the eye. It consists of a central stroma that constitutes 90% of the corneal depth, covered anteriorly with epithelium and posteriorly with endothelium. Its transparency is the result of the regular spacing of collagen fibers with remarkably uniform diameter and interfibrillar space. Corneal collagen is composed of heterotypic fibrils consisting of type I and type V collagen molecules. Th...

  17. Carotid intima-media thickness and apolipoproteins in patients of ischemic stroke in a rural hospital setting in central India: A cross-sectional study

    OpenAIRE

    Jyoti Jain; Tejal Lathia; Om Prakash Gupta; Vishakha Jain

    2012-01-01

    Context: Carotid intima-media thickness (CIMT) and apolipoproteins have been found as a risk factor for ischemic stroke . Objective: The objective was to study the carotid intima-media thickness, apolipoproteins, and their relation in patients of ischemic stroke in central rural India. Settings and Design: A cross-sectional study was performed in a rural hospital in central India. Materials and Methods: In all patients of ischemic stroke proven by computerized tomography (CT), CIMT, apolipopr...

  18. New therapeutic modality for corneal endothelial disease using Rho-associated kinase inhibitor eye drops.

    Science.gov (United States)

    Koizumi, Noriko; Okumura, Naoki; Ueno, Morio; Kinoshita, Shigeru

    2014-11-01

    Corneal endothelial dysfunction accompanied by visual disturbance is a primary indication for corneal endothelial transplantation. However, despite the value and potential of endothelial graft surgery, a strictly pharmacological approach for treating corneal endothelial dysfunction remains an attractive proposition. Previously, we reported that the selective Rho-associated kinase (ROCK) inhibitor Y-27632 promotes cell adhesion and proliferation, and inhibits the apoptosis of primate corneal endothelial cells in culture. These findings have led us to develop a novel medical treatment for the early phase of corneal endothelial disease using ROCK inhibitor eye drops. In rabbit and monkey models of partial endothelial dysfunction, we showed that corneal endothelial wound healing was accelerated via the topical application of ROCK inhibitor to the ocular surface, resulting in the regeneration of a corneal endothelial monolayer with a high endothelial cell density. Based on these animal studies, we are now attempting to advance the clinical application of ROCK inhibitor eye drops for patients with corneal endothelial dysfunction. A pilot clinical study was performed at the Kyoto Prefectural University of Medicine, and the effects of Y-27632 eye drops after transcorneal freezing were evaluated in 8 patients with corneal endothelial dysfunction. We observed a positive effect of ROCK inhibitor eye drops in treating patients with central edema caused by Fuchs corneal endothelial dystrophy. We believe that our new findings will contribute to the establishment of a new approach for the treatment of corneal endothelial dysfunction. PMID:25289721

  19. Influence of corneal collagen crosslinking with riboflavin and ultraviolet-a irradiation on excimer laser surgery.

    NARCIS (Netherlands)

    Kampik, D.; Ralla, B.; Keller, S.; Hirschberg, M.; Friedl, P.H.A.; Geerling, G.

    2010-01-01

    PURPOSE: Riboflavin/ultraviolet A (UVA) cross-linking (CXL) of corneal collagen is a novel method of stabilizing corneal mechanical properties and preventing progression of keratectasias. This study was conducted to investigate whether CXL influences ablation rate, flap thickness, and refractive res

  20. Corneal endothelium after deep anterior lamellar keratoplasty and penetrating keratoplasty for keratoconus: A four-year comparative study

    Directory of Open Access Journals (Sweden)

    Anil Kubaloglu

    2012-01-01

    Full Text Available Purpose: To compare the status of corneal endothelium and central corneal thickness within the first four postoperative years after deep anterior lamellar keratoplasty (DALK and penetrating keratoplasty (PK in patients with keratoconus. Materials and Methods: Thirty-nine eyes (Group A which had PK and 44 eyes (Group B which had DALK for the treatment of keratoconus were included in this retrospective study. The endothelial cell density (ECD, the mean endothelial cell area and the coefficient of variation of cell area were assessed with a non-contact specular microscope, and the central corneal thickness (CCT was measured with an ultrasound pachymeter. Results: Mean ECD loss rate at two years was 36.24% in Group A and 18.12% in Group B (P<0.001. Mean ECD loss rate at four years was 47.82% in Group A and 21.62% in Group B (P<0.001. Mean annual ECD loss rate was calculated 14.12% per year in Group A and 5.78% per year in Group B. In the PK group, increase in mean CCT was 15.60% in two years and 15.03% in four years, while in the DALK group, mean CCT increased by 8.05% in two years and 9.31% in four years. Conclusions: As the majority of ectatic disorders such as keratoconus occur in young people, long-term endothelial cell survival following treatment with keratoplasty is essential for the long-term visual ability. Our finding that corneal endothelial cell loss in the DALK group occurs at a slower rate than in the PK group suggests DALK as a safer alternative to PK in these selected patients.

  1. Isolation of bovine corneal keratan sulfate and its growth factor and morphogen binding

    OpenAIRE

    Weyers, Amanda; Yang, Bo; Solakyildirim, Kemal; Yee, Vienna; Li, Lingyun; Zhang, Fuming; Linhardt, Robert

    2013-01-01

    Keratan sulfate (KS) is an important glycosaminoglycan that is found in cartilage, reproductive, and neural tissues. Corneal KS glycosaminoglycan is found N-linked to lumican, keratocan, and mimecan proteoglycans and has been widely studied by investigators interested in corneal development and diseases. Recently, the availability of corneal KS has become severely limited due to restricted the shipment of bovine central nervous system by-products across international borders in efforts to pre...

  2. Mosaic analysis of stem cell function and wound healing in the mouse corneal epithelium

    Directory of Open Access Journals (Sweden)

    Morley Steven D

    2009-01-01

    Full Text Available Abstract Background The mouse corneal epithelium is a continuously renewing 5–6 cell thick protective layer covering the corneal surface, which regenerates rapidly when injured. It is maintained by peripherally located limbal stem cells (LSCs that produce transient amplifying cells (TACs which proliferate, migrate centripetally, differentiate and are eventually shed from the epithelial surface. LSC activity is required both for normal tissue maintenance and wound healing. Mosaic analysis can provide insights into LSC function, cell movement and cell mixing during tissue maintenance and repair. The present study investigates cell streaming during corneal maintenance and repair and changes in LSC function with age. Results The initial pattern of corneal epithelial patches in XLacZ+/- X-inactivation mosaics was replaced after birth by radial stripes, indicating activation of LSCs. Stripe patterns (clockwise, anticlockwise or midline were independent between paired eyes. Wound healing in organ culture was analysed by mosaic analysis of XLacZ+/- eyes or time-lapse imaging of GFP mosaics. Both central and peripheral wounds healed clonally, with cells moving in from all around the wound circumference without significant cell mixing, to reconstitute striping patterns. Mosaic analysis revealed that wounds can heal asymmetrically. Healing of peripheral wounds produced stripe patterns that mimicked some aberrant striping patterns observed in unwounded corneas. Quantitative analysis provided no evidence for an uneven distribution of LSC clones but showed that corrected corneal epithelial stripe numbers declined with age (implying declining LSC function but stabilised after 39 weeks. Conclusion Striping patterns, produced by centripetal movement, are defined independently and stochastically in individual eyes. Little cell mixing occurs during the initial phase of wound healing and the direction of cell movement is determined by the position of the wound

  3. A 90 m-thick coal seam in the Lubstow lignite deposit (Central Poland): palynological analysis and sedimentary environment

    Energy Technology Data Exchange (ETDEWEB)

    Durska, E. [University of Warsaw, Warsaw (Poland). Faculty of Geology

    2008-07-01

    A 90 m-thick brown coal seam, the result of organic matter deposition in a fault-trough, is exploited in an open cast mine at Lubstow (Central Poland). Palynological analysis was conducted in order to determine which plants were the source of organic matter forming such a thick coal bed. The pollen spectrum is dominated by the gymnosperm pollen Inaperturopollenites, produced by trees closely related to the extant genera Taxodium and Glyptostrobus, the dominant constituents of swamp forests in SE North America and SE Asia today. However the lack of xylites and preserved tissues in the coal does not support the conception of a swamp forest as the peat-producing community. There is also significant percentage of angiosperm pollen in the coal, mainly from the groups: Castaneoideapollis, Tricolporopollenites exactus and T. pseudocingulum. The plants producing these pollen were probably the main constitutent of the peat-producing community. The community shows signs of a shrub swamp with local tree islands and a low water table. Evidence for this also includes the detrital type of coal, the lack of preserved plant tissues and the presence of fungal remains. The characteristics show the existence of aerobic zones at the time of peat production. The peat was probably derived from angiosperms. Dome-shaped forms in the upper part of the deposit are the remains of tree islands. As detritus accumulation is very on the surfaces of present-day tree islands, a similar rate of deposition may have taken place during peat production at Lubstow. This, combined with subsidence in the fault-through, explains the great thickness of the coal bed.

  4. Ice thickness, volume and subglacial topography of Urumqi Glacier No. 1, Tianshan mountains, central Asia, by ground penetrating radar survey

    Indian Academy of Sciences (India)

    Puyu Wang; Zhongqin Li; Shuang Jin; Ping Zhou; Hongbing Yao; Wenbin Wang

    2014-04-01

    The results of radar survey for three times are presented, aiming to determine ice thickness, volume and subglacial topography of Urumqi Glacier No. 1, Tianshan Mountains, central Asia. Results show that the distribution of ice is more in the center and lesser at both ends of the glacier. The bedrock is quite regular with altitudes decreasing towards the ice front, showing the U-shaped subglacial valley. By comparison, typical ice thinning along the centerline of the East Branch of the glacier was 10–18 m for the period 1981–2006, reaching a maximum of ∼30 m at the terminus. The corresponding ice volume was 10296.2 × 104 m3, 8797.9 × 104 m3 and 8115.0 × 104 m3 in 1981, 2001 and 2006, respectively. It has decreased by 21.2% during the past 25 years, which is the direct result of glacier thinning. In the same period, the ice thickness, area and terminus decreased by 12.2%, 10.3%, and 3.6%, respectively. These changes are responses to the regional climatic warming, which show a dramatic increase of 0.6°C (10 a)−1 during the period 1981–2006.

  5. An Association between Corneal Inflammation and Corneal Lymphangiogenesis after Keratoplasty

    Institute of Scientific and Technical Information of China (English)

    Weihua Li; Wencong Wang; Shiqi Ling

    2014-01-01

    Purpose:To examine the relationship between corneal in-flammation and corneal lymphangiogenesis after keratoplasty. Methods:.Rat corneal lymphangiogenesis was examined by lymphatic vessel endothelial receptor (LYVE-1) immunohis-tochemistry and whole mount immunofluorescence at 1, 3, 7, 10, and 14 days after corneal transplantation. Corneal inflam-mation was evaluated by inflammation index (IF) grading and NF-κB immunohistochemistry at the same time points. The association between lymphatic vessel counting (LVC) and the IF scores was then examined. Results:.LYVE-1 positive lymphatic vessels occurred in the corneal stroma on day 3,.developed throughout days 7 and 10,.and peaked in number at day 14 after keratoplasty. Corneal inflammation was strong on day 3, and then resolved gradually,.but increased again from days 7 to 14 after the transplantation..LVC was strongly and positively correlated with IF after keratoplasty(r=0.41;P<0.05). However, changes in IF scores and LVC were not parallel. Conclusion:.A close,.but not parallel,.relationship was found between corneal lymphangiogenesis and corneal inflammation after corneal transplantation.

  6. Isolation of bovine corneal keratan sulfate and its growth factor and morphogen binding.

    Science.gov (United States)

    Weyers, Amanda; Yang, Bo; Solakyildirim, Kemal; Yee, Vienna; Li, Lingyun; Zhang, Fuming; Linhardt, Robert J

    2013-05-01

    Keratan sulfate (KS) is an important glycosaminoglycan that is found in cartilage, reproductive tissues, and neural tissues. Corneal KS glycosaminoglycan is found N-linked to lumican, keratocan and mimecan proteoglycans, and has been widely studied by investigators interested in corneal development and diseases. Recently, the availability of corneal KS has become severely limited, owing to restrictions on the shipment of bovine central nervous system byproducts across international borders in an effort to prevent additional cases of mad cow disease. We report a simple method for the purification of multi-milligram quantities of bovine corneal KS, and characterize its structural properties. We also examined its protein-binding properties, and discovered that corneal KS bound with high affinity to fibroblast growth factor-2 and sonic hedgehog, a growth factor and a morphogen involved in corneal development and healing. PMID:23402351

  7. Genetics of corneal endothelial dystrophies

    Indian Academy of Sciences (India)

    Chitra Kannabiran

    2009-12-01

    The corneal endothelium maintains the level of hydration in the cornea. Dysfunction of the endothelium results in excess accumulation of water in the corneal stroma, leading to swelling of the stroma and loss of transparency. There are four different corneal endothelial dystrophies that are hereditary, progressive, non-inflammatory disorders involving dysfunction of the corneal endothelium. Each of the endothelial dystrophies is genetically heterogeneous with different modes of transmission and/or different genes involved in each subtype. Genes responsible for disease have been identified for only a subset of corneal endothelial dystrophies. Knowledge of genes involved and their function in the corneal endothelium can aid understanding the pathogenesis of the disorder as well as reveal pathways that are important for normal functioning of the endothelium.

  8. Comparative Study of Anterior Eye Segment Measurements with Spectral Swept-Source and Time-Domain Optical Coherence Tomography in Eyes with Corneal Dystrophies

    Directory of Open Access Journals (Sweden)

    Anna K. Nowinska

    2015-01-01

    Full Text Available Purpose. To compare anterior eye segment measurements and morphology obtained with two optical coherence tomography systems (TD OCT, SS OCT in eyes with corneal dystrophies (CDs. Methods. Fifty healthy volunteers (50 eyes and 54 patients (96 eyes diagnosed with CD (epithelial basement membrane dystrophy, EBMD = 12 eyes; Thiel-Behnke CD = 6 eyes; lattice CD TGFBI type = 15 eyes; granular CD type 1 = 7 eyes, granular CD type 2 = 2 eyes; macular CD = 23 eyes; and Fuchs endothelial CD = 31 eyes were recruited for the study. Automated and manual central corneal thickness (aCCT, mCCT, anterior chamber depth (ACD, and nasal and temporal trabecular iris angle (nTIA, tTIA were measured and compared with Bland-Altman plots. Results. Good agreement between the TD and SS OCT measurements was demonstrated for mCCT and aCCT in normal individuals and for mCCT in the CDs group. The ACD, nTIA, and tTIA measurements differed significantly in both groups. TBCD, LCD, and FECD caused increased CCT. MCD caused significant corneal thinning. FECD affected all analyzed parameters. Conclusions. Better agreement between SS OCT and TD OCT measurements was demonstrated in normal individuals compared to the CDs group. OCT provides comprehensive corneal deposits analysis and demonstrates the association of CD with CCT, ACD, and TIA measurements.

  9. Contact Lens Related Corneal Ulcer

    OpenAIRE

    Loh, KY; P Agarwal

    2010-01-01

    A corneal ulcer caused by infection is one of the major causes of blindness worldwide. One of the recent health concerns is the increasing incidence of corneal ulcers associated with contact lens user especially if the users fail to follow specific instruction in using their contact lenses. Risk factors associated with increased risk of contact lens related corneal ulcers are: overnight wear, long duration of continuous wear, lower socio-economic classes, smoking, dry eye and poor hygiene. Th...

  10. A Case of Solitary Nonvascularized Corneal Epithelial Dysplasia

    Directory of Open Access Journals (Sweden)

    Tomoya Morii

    2016-01-01

    Full Text Available Background. Epithelial dysplasia is categorized as conjunctival/corneal intraepithelial neoplasia which is a precancerous lesion. The lesion is usually developed at the limbal region and grows towards central cornea in association with neovascularization into the lesion. Here, we report a case of isolated nonvascularized corneal epithelial dysplasia surrounded by normal corneal epithelium with immune histochemical finding of ocular surface tissues cytokeratins, for example, keratin 13 and keratin 12. Case Presentation. A 76-year-old man consulted us for visual disturbance with localized opacification of the corneal epithelium in his left eye. His visual acuity was 20/20 and 20/200 in his right and left eye, respectively. Slit lamp examination showed a whitish plaque-like lesion at the center of his left corneal epithelium. No vascular invasion to the lesion was found. The lesion was surgically removed and subjected to histopathological examination and diagnosed as epithelial dysplasia. Amyloidosis was excluded by direct fast scarlet 4BS (DFS staining. Immunohistochemistry showed that the dysplastic epithelial cells express keratin 13 and vimentin, but not keratin 12, indicating that the neoplastic epithelial cells lacked corneal-type epithelium differentiation. Conclusions. The lesion was diagnosed as nonvascularized epithelial dysplasia of ocular surface. Etiology of the lesion is not known.

  11. A Case of Solitary Nonvascularized Corneal Epithelial Dysplasia

    Science.gov (United States)

    Morii, Tomoya; Sumioka, Takayoshi; Izutani-Kitano, Ai; Takada, Yukihisa; Okada, Yuka; Kao, Winston W.-Y.; Saika, Shizuya

    2016-01-01

    Background. Epithelial dysplasia is categorized as conjunctival/corneal intraepithelial neoplasia which is a precancerous lesion. The lesion is usually developed at the limbal region and grows towards central cornea in association with neovascularization into the lesion. Here, we report a case of isolated nonvascularized corneal epithelial dysplasia surrounded by normal corneal epithelium with immune histochemical finding of ocular surface tissues cytokeratins, for example, keratin 13 and keratin 12. Case Presentation. A 76-year-old man consulted us for visual disturbance with localized opacification of the corneal epithelium in his left eye. His visual acuity was 20/20 and 20/200 in his right and left eye, respectively. Slit lamp examination showed a whitish plaque-like lesion at the center of his left corneal epithelium. No vascular invasion to the lesion was found. The lesion was surgically removed and subjected to histopathological examination and diagnosed as epithelial dysplasia. Amyloidosis was excluded by direct fast scarlet 4BS (DFS) staining. Immunohistochemistry showed that the dysplastic epithelial cells express keratin 13 and vimentin, but not keratin 12, indicating that the neoplastic epithelial cells lacked corneal-type epithelium differentiation. Conclusions. The lesion was diagnosed as nonvascularized epithelial dysplasia of ocular surface. Etiology of the lesion is not known. PMID:27042371

  12. Weekly periodicities of aerosol optical thickness over Central Europe – evidence of an anthropogenic direct aerosol effect

    Directory of Open Access Journals (Sweden)

    B. Vogel

    2007-08-01

    Full Text Available Statistical analyses of data from 14 ground-based sun photometer stations all over Central Europe are presented. All stations are part of the Aerosol Robotic Network (AERONET, and only data of the highest data quality level 2.0 had been applied. The averages by weekday of aerosol optical thickness (AOT at a wavelength of 440 nm of 12 of the 14 stations show a weekly periodicity with lowest values on Sunday and Monday, but greatest values from Wednesday until Saturday, that is significant at least on a 90% level. The stations in Germany and in Greater Paris show weekly cycles with ranges of about 20% on average. In Northern Italy and Switzerland this range is about 10% on average. The corresponding weekly cycle of anthropogenic gaseous and particulate emissions leads us to the conclusion of the anthropogenic origin of the weekly AOT cycle. Since these AOT patterns are derived from the reduction of the direct sun radiation by the columnar atmospheric aerosol, this result represents strong evidence for an anthropogenic direct aerosol effect on shortwave radiation. Furthermore, this study makes a first contribution to the understanding and explanation of recently observed weekly periodicities in meteorological variables as temperature in Germany.

  13. Comparison of aspheric keratectomy excimer laser subepithelial keratomileusis (LASEK)and aspheric laser in situ keratomileusis(LASIK) for different thickness corneal%非球面切削LASEK和LASIK治疗不同厚度角膜的高度近视

    Institute of Scientific and Technical Information of China (English)

    朱云喜; 金敏; 王小园; 高宗银; 杨为中; 朱远军

    2010-01-01

    目的 探讨角膜波前像差联合Q值优化的非球面切削准分子激光上皮下角膜切削术(LASEK)与角膜波前像差联合Q值优化的非球面切削准分子激光原位角膜磨镶术(LASIK),分别治疗角膜薄(500μm)的高度近视的临床疗效比较.方法 选取角膜厚度薄的高度近视患者行LASEK治疗25例(42只眼),角膜厚的高度近视患者38例(65只眼),比较术前视力、年龄、角膜厚度、切削厚度、剩余角膜厚度、等效球镜度、球差、慧差、总阶像差,术后2周,4周,3月,6月的视力,比较术后6月两组视力、等效球镜度、球差、慧差、总阶像差、HAZE等级.结果 两种手术方式术后6月内的视力,术后6月的等效球镜度、球差、慧差、总阶像差均无统计学意义,治疗高度近视具有相同均具有很高的安全性、有效性及可预测性且两组具有相同的临床疗效.结论 非球面切削的LASEK治疗角膜薄的高度近视与非球面切削的LASIK治疗角膜厚的高度近视具有相同的临床疗效.%Objective To compare the clinical curative effect of corneal wavefront-guided combining Q-value guided aspheric keratctomy excimer LASEK for high myopia of thin cornea (500μm). Methods Of selected 25 high myopia of thin cornea (42 eyes), and 38 high myopia of thick cornea (65 eyes), compared the preoperative uncorrected visual acuity (UCVA), age, corneal thickness, atherectomy thickness,remnant thickness, spherical equivalent (SE), Coma-like RMS (root of mean square), spherical-like RMS,RMSg (root of mean square of general aberration) with postoperative UCVA of 2, 4 weeks, 1 month, 3, 6 months SE, Coma-like RMS, spherical-like RMS, RMSg, Level of Haze. Results There were no statistically significant differences between two groups 6 months aiter operation in UCVA, spherical equivalent (SE),Coma-like RIMS, spherical-like RMS and RMSg. Both groups showed high safety, efficacy, predictability and the same clinical curative effect

  14. Transient corneal edema after phacoemulsification

    International Nuclear Information System (INIS)

    Objective: To determine the association between pre-operative and intra-operative factors leading to transient corneal edema after phacoemulsification. Study Design: Cohort study. Place and Duration of Study: Department of Ophthalmology, Shifa Foundation Community Health Centre, Islamabad, from October 2011 to September 2012. Methodology: Patients undergoing phacoemulsification and Intraocular Lens (IOL) implantation were enrolled in the study using consecutive non-probability sampling. Pre-operative risk factors including peripheral corneal degenerations, the type and density of cataract were documented. Surgical risk factors included the incision site, the type of intraocular lens, the phacotechnique and the phacopower time. Postoperatively the patients were assessed for corneal clarity and the degree of striate keratopathy. Statistical analysis was done using SPSS version 17. Results: There were 43% male and 57% female patients (n = 182). Mean age was 58.92 ± 13.00 years (median and mode-60 years). Factors which increased the risk of transient corneal edema after phacoemulsification included hypertension (p = 0.022), dense nuclear cataracts (p=0.006), divide and conquer technique (p = 0.008), duration of phacopower use (p < 0.001) and peripheral corneal degenerations (p < 0.001). Conclusion: Patients with peripheral corneal degenerations and dense nuclear cataracts had significantly higher rates of postoperative corneal edema. Use of phaco-chop technique and less phaco-power time helps in decreasing corneal edema. (author)

  15. Geophysical Investigations on Malta (Central Mediterranean) using Ambient Noise: Assessing Array Performance and Influence of a Thick Low Velocity Layer.

    Science.gov (United States)

    Farrugia, D.; Paolucci, E.; D'Amico, S.; Galea, P. M.

    2014-12-01

    The use of microtremors to obtain shear wave velocity (Vs) profiles of the subsurface is becoming a widespread approach due to its various advantages. Noise measurements were carried out at four sites on Malta (Central Mediterranean). Array techniques were first tested in an area where a ≈45 m layer of soft Blue Clay (BC) overlies the harder limestone. Three array configurations (two arrays of 17 geophones in an L-shape and circle respectively and one 42 geophone array in an L-shape) were tested and processed using the f-k and two SPAC techniques: Modified and Extended SPAC. No significant difference was observed in the dispersion curve from the two short arrays despite having different shapes. However, a significant variation was observed between the dispersion curve from the long and short arrays in the low frequency part. A joint inversion, using two direct search methods, of the dispersion and the H/V curve was then used to obtain the Vs profile for the site, with most of the profiles being in agreement both in terms of velocity and depth. A study was also conducted at three other sites on Malta where hard Upper Coralline Limestone (UCL) overlies the soft BC creating a velocity inversion in the soil profile. The shape of the effective dispersion curves obtained using ESAC show both an inverse dispersive trend and normal dispersion. This shape is tentatively explained in terms of the presence of higher mode Rayleigh waves. A Genetic Algorithm approach was then used to jointly invert the H/V and Rayleigh wave dispersion curve. It was observed that the BC velocity was higher when overlain by a large thickness of UCL. This could be linked to the effective pressure caused by the hard UCL, making the BC more compact, and having a higher velocity. The theoretical implications of a prominent low-velocity layer on site amplification and the interpretation of ambient noise data are investigated and discussed.

  16. Advances in corneal cell therapy.

    Science.gov (United States)

    Fuest, Matthias; Yam, Gary Hin-Fai; Peh, Gary Swee-Lim; Mehta, Jodhbir S

    2016-09-01

    Corneal integrity is essential for visual function. Transplantation remains the most common treatment option for advanced corneal diseases. A global donor material shortage requires a search for alternative treatments. Different stem cell populations have been induced to express corneal cell characteristics in vitro and in animal models. Yet before their application to humans, scientific and ethical issues need to be solved. The in vitro propagation and implantation of primary corneal cells has been rapidly evolving with clinical practices of limbal epithelium transplantation and a clinical trial for endothelial cells in progress, implying cultivated ocular cells as a promising option for the future. This review reports on the latest developments in primary ocular cell and stem cell research for corneal therapy. PMID:27498943

  17. Corneal Transplant Infection due to Alternaria alternata: A Case Report

    Directory of Open Access Journals (Sweden)

    Vasileios Konidaris

    2013-01-01

    Full Text Available Purpose. To report a case of Alternaria alternata keratitis in a patient with a corneal transplant in her right eye due to bullous pseudophakic keratopathy. Methods. A 66-year-old female underwent a full-thickness keratoplasty in her right eye due to bullous pseudophakic keratopathy. Three weeks after keratoplasty, epithelial edema and a stromal opacity with an infiltrate and development of peripheral corneal opacities appeared. The diagnosis of Alternaria alternata keratitis was made. Results. The patient underwent a second keratoplasty, due to the corneal melting as a result of the fungal infection. She was also given combined antifungal treatment locally and systematically. Conclusion. Corneal transplantation alone would not have been sufficient to keep the fungus in the anterior portion of the eye. Combined antifungal treatment, locally and systematically, was important in attempting to prevent the further spread of the fungus to the interior of the eye. To our knowledge, the case presented here is only the second one in the literature concerning a keratomycosis due to Alternaria alternata corneal transplant infection.

  18. Concise Review: An Update on the Culture of Human Corneal Endothelial Cells for Transplantation.

    Science.gov (United States)

    Parekh, Mohit; Ferrari, Stefano; Sheridan, Carl; Kaye, Stephen; Ahmad, Sajjad

    2016-02-01

    The cornea forms the front window of the eye, enabling the transmission of light to the retina through a crystalline lens. Many disorders of the cornea lead to partial or total blindness, and therefore corneal transplantation becomes mandatory. Recently, selective corneal layer (as opposed to full thickness) transplantation has become popular because this leads to earlier rehabilitation and visual outcomes. Corneal endothelial disorders are a common cause of corneal disease and transplantation. Corneal endothelial transplantation is successful but limited worldwide because of lower donor corneal supply. Alternatives to corneal tissue for endothelial transplantation therefore require immediate attention. The field of human corneal endothelial culture for transplantation is rapidly emerging as a possible viable option. This manuscript provides an update regarding these developments. Significance: The cornea is the front clear window of the eye. It needs to be kept transparent for normal vision. It is formed of various layers of which the posterior layer (the endothelium) is responsible for the transparency of the cornea because it allows the transport of ions and solutes to and from the other layers of the cornea. Corneal blindness that results from the corneal endothelial dysfunction can be treated using healthy donor tissues. There is a huge demand for human donor corneas but limited supply, and therefore there is a need to identify alternatives that would reduce this demand. Research is underway to understand the isolation techniques for corneal endothelial cells, culturing these cells in the laboratory, and finding possible options to transplant these cells in the patients. This review article is an update on the recent developments in this field. PMID:26702128

  19. Corneal Cross-Linking (with a Partial Deepithelization) in Keratoconus with Five Years of Follow-Up

    Science.gov (United States)

    Galvis, Virgilio; Tello, Alejandro; Carreño, Néstor I.; Ortiz, Alvaro I.; Barrera, Rodrigo; Rodriguez, Carlos Julián; Ochoa, Miguel E.

    2016-01-01

    We performed a retrospective interventional case series including 80 eyes of 48 patients with keratoconus (KC) who were treated with modified corneal cross-linking (CXL) for KC (with a partial deepithelization in a pattern of stripes). The average follow-up was 5.8 years (with a minimum of 5 years). At the last follow-up visit, compared with preoperative values, there were no significant changes in spherical equivalent, average keratometry, corneal thickness, corneal hysteresis, or corneal resistance factor. The distance-corrected visual acuity was 20/39 preoperatively and 20/36 postoperatively (P = 0.3). The endothelial cell count decreased by 4.7% (P < 0.005). These findings suggest that this modified corneal CXL technique is a safe and effective alternative to halt the progression of KC up to five years after the procedure. However, some concerns remain as to whether this technique can affect in some degree the corneal endothelial cells. PMID:27199574

  20. Surface Modification of PMMA to Improve Adhesion to Corneal Substitutes in a Synthetic Core-Skirt Keratoprosthesis.

    Science.gov (United States)

    Riau, Andri K; Mondal, Debasish; Yam, Gary H F; Setiawan, Melina; Liedberg, Bo; Venkatraman, Subbu S; Mehta, Jodhbir S

    2015-10-01

    Patients with advanced corneal disease do poorly with conventional corneal transplantation and require a keratoprosthesis (KPro) for visual rehabilitation. The most widely used KPro is constructed using poly(methyl methacrylate) (PMMA) in the central optical core and a donor cornea as skirt material. In many cases, poor adherence between the PMMA and the soft corneal tissue is responsible for device "extrusion" and bacterial infiltration. The interfacial adhesion between the tissue and the PMMA was therefore critical to successful implantation and device longevity. In our approach, we modified the PMMA surface using oxygen plasma (plasma group); plasma followed by calcium phosphate (CaP) coating (p-CaP); dopamine followed by CaP coating (d-CaP); or plasma followed by coating with (3-aminopropyl)triethoxysilane (3-APTES). To create a synthetic KPro model, we constructed and attached 500 μm thick collagen type I hydrogel on the modified PMMA surfaces. Surface modifications produced significantly improved interfacial adhesion strength compared to untreated PMMA (p strength was observed in p-CaP group over time (p human corneal stromal fibroblasts, except for the 3-APTES group, which showed no live cells at 72 h of culture. In contrast, cells on d-CaP surface showed good anchorage, evidenced by the expression of focal adhesion complex (paxillin and vinculin), and prominent filopodia protrusions. In conclusion, d-CaP can not only enhance and provide stability to the adhesion of collagen hydrogel on the PMMA surface but also promote biointegration. PMID:26389670

  1. LIM Homeobox Domain 2 Is Required for Corneal Epithelial Homeostasis.

    Science.gov (United States)

    Sartaj, Rachel; Chee, Ru-ik; Yang, Jing; Wan, Pengxia; Liu, Aihong; Guaiquil, Victor; Fuchs, Elaine; Rosenblatt, Mark I

    2016-02-01

    The cornea requires constant epithelial renewal to maintain clarity for appropriate vision. A subset of stem cells residing at the limbus is primarily responsible for maintaining corneal epithelium homeostasis. Trauma and disease may lead to stem cell deficiency and therapeutic targeting to replenish the stemness capacity has been stalled by the lack of reliable corneal epithelial stem cell markers. Here we identified the location of Lhx2 in mice (mLhx2) cornea and conjunctival tissue using an Lhx2eGFP reporter model and in human tissues (hLHX2). Lhx2 localized to the basal cells of central cornea, the conjunctiva and the entire limbal epithelium in humans and mice. To ascribe a functional role we generated Lhx2 conditional knockout (cKO) mice and the phenotypic effects in corneas were analyzed by slit lamp microscopy, in cell-based assays and in a model of corneal epithelium debridement. Immunodetection on corneal sections were used to visualize conjunctivalization, a sign of limbal barrier failure. Lhx2cKO mice produced reduced body hair and spontaneous epithelial defects in the cornea that included neovascularization, perforation with formation of scar tissue and opacification. Cell based assays showed that Lhx2cKO derived corneal epithelial cells have a significantly lower capacity to form colonies over time and delayed wound-healing recovery when compared to wildtype cells. Repeated corneal epithelial wounding resulted in decreased re-epithelialization and multiple cornea lesions in Lhx2cKO mice compared to normal recovery seen in wildtype mice. We conclude that Lhx2 is required for maintenance of the corneal epithelial cell compartment and the limbal barrier. PMID:26661907

  2. Femtosecond laser-assisted keratoplasty in a child with corneal opacity:case report

    Directory of Open Access Journals (Sweden)

    E. Yu. Markova

    2014-01-01

    Full Text Available Corneal opacities are the fourth cause of blindness world-wide. Over the past two centuries, various corneal transplantation (i.e., keratoplasty methods have been developed and improved. Nowadays, femtolaserssisted keratoplasty is one of most promising techniques. Femtosecond laser have several advantages that provide additional surgical benefits. Among them, no thermal injury, the ability to cut deeply on a single plane and to perform various corneal profiles should be mentioned. In children, corneal disorders are of special importance while femtosecondassisted keraatoplasty case reports are rare. Here, we describe femtosecond laserssisted penetrating keratoplasty in a girl with a rough central corneal opacity.

  3. Spontaneous corneal perforation in an eye with Peters' anomaly

    Directory of Open Access Journals (Sweden)

    Kim M

    2013-07-01

    Full Text Available Moosang Kim, Seung-Chan Lee, Seung-Jun Lee Department of Ophthalmology, School of Medicine, Kangwon National University, Chuncheon, South Korea Abstract: A premature female infant underwent her first ophthalmologic examination at the age of 4 weeks. The initial examination of the baby was requested for evaluation of a ‘white spot’ on the surface of her right eye. She had been hospitalized in the neonatal intensive care unit because of systemic abnormalities, such as a right clavicle fracture and microcephaly. Slit-lamp examination of the right eye showed a central corneal opacity, corneal thinning, and an iridocorneal adhesion. The lens and fundus of the right eye could not be observed. We observed no pathologic findings in the left eye. The baby's parents were informed of the high risk for spontaneous corneal perforation without external pressure. At 42 days of age, an ophthalmologic examination of the infant was again requested for evaluation of ‘tears’ from her right eye 3 hours previously. Examination revealed corneal perforation, iris protrusion, and a flat anterior chamber. We performed emergent conjunctival flap surgery. Three months following surgery, the patient's right eye was successfully preserved with no sign of inflammation or leakage. Keywords: conjunctival flap, corneal perforation, Peters' anomaly

  4. Microtubule regulation of corneal fibroblast morphology and mechanical activity in 3-D culture

    OpenAIRE

    Kim, Areum; Petroll, W. Matthew

    2007-01-01

    The purpose of this study was to investigate the role of microtubules in regulating corneal fibroblast structure and mechanical behavior using static (3-D) and dynamic (4-D) imaging of both cells and their surrounding matrix. Human corneal fibroblasts transfected to express GFP-zyxin (to label focal adhesions) or GFP-tubulin (to label microtubules) were plated at low density inside 100 μm thick type I collagen matrices. After 24 hours, the effects of nocodazole (to depolymerize microtubules),...

  5. Changes in the micromorphology of the corneal subbasal nerve plexus in patients after plaque brachytherapy

    International Nuclear Information System (INIS)

    To quantify the development of radiation neuropathy in corneal subbasal nerve plexus (SNP) after plaque brachytherapy, and the subsequent regeneration of SNP micromorphology and corneal sensation. Nine eyes of 9 melanoma patients (ciliary body: 3, iris: 2, conjunctiva: 4) underwent brachytherapy (ruthenium-106 plaque, dose to tumour base: 523 ± 231 Gy). SNP micromorphology was assessed by in-vivo confocal microscopy. Using software developed in–house, pre-irradiation findings were compared with those obtained after 3 days, 1, 4 and 7 months, and related to radiation dose and corneal sensation. After 3 days nerve fibres were absent from the applicator zone and central cornea, and corneal sensation was abolished. The earliest regenerating fibres were seen at the one-month follow-up. By 4 months SNP structures had increased to one-third of pre-treatment status (based on nerve fibre density and nerve fibre count), and corneal sensation had returned to approximately two-thirds of pre-irradiation values. Regeneration of SNP and corneal sensation was nearly complete 7 months after plaque brachytherapy. The evaluation of SNP micromorphology and corneal sensation is a reliable and clinically useful method for assessing neuropathy after plaque brachytherapy. Radiation-induced neuropathy of corneal nerves develops quickly and is partly reversible within 7 months. The clinical impact of radiation-induced SNP damage is moderate

  6. Using skew-symmetric mixed models for investigating the effect of different diabetic macular edema treatments by analyzing central macular thickness and visual acuity responses

    OpenAIRE

    Marjan Mansourian; Anoshirvan Kazemnejad; Iraj Kazemi; Farid Zayeri; Masoud Soheilian

    2011-01-01

    Background: Diabetic Macular Edema (DME) is one of the major causes of visual loss and increase in central macular thickness (CMT). The aim of this study was to determine the efficacy of a single intravitreal injection of bevacizumab (IVB) alone or in combination with intravitreal triamcinolone acetonide (IVB/IVT) versus macular laser photocoagulation (MPC) as primary treatment for DME when confounders were considered. Methods: Skew-symmetric bivariate mixed modeling according to best cor...

  7. [Transplantation of corneal endothelial cells].

    Science.gov (United States)

    Amano, Shiro

    2002-12-01

    Though conventional corneal transplantation has achieved great success, it still has several drawbacks including limited availability of donor corneas, recurrent allograft rejection, and subsequent graft failure in certain cases. Reconstructing clinically usable corneas by applying the technology of regenerative medicine can offer a solution to these problems, as well as making corneal transplantation a non-emergency surgery and enabling the usage of banked corneal cells. In the present study, we focused on corneal endothelium that is critical for corneal transparency and investigated the reconstruction of cornea utilizing cultured human corneal endothelial cells (HCECs). We succeeded in steadily culturing HCECs by using culture dishes pre-coated with extracellular matrix produced by calf corneal endothelial cells and culture media that contained basic fibroblast growth factor and fetal bovine serum. We performed the following analysis utilizing these cultured HCECs. The older the donor was, the more frequently large senescent cells appeared in the passaged HCECs. The telomeres of HCECs were measured as terminal restriction fragments (TRF) by Southern blotting. HCECs, in vivo from donors in their seventies had a long TRFs of over 12 kilobases. Passaging shortened the TRFs but there was no difference in TRFs among donors of various ages. These results indicated that shortening of telomere length is not related to senescence of HCECs. We investigated the role of advanced glycation end products (AGEs) in the senescence of in vivo HCECs. The results indicated that AGE-protein in the aqueous humor is endocytosed into HCECs via AGE receptors expressed on the surface of HCECs and damages HCECs by producing reactive oxygen species and inducing apoptosis, suggesting that AGEs, at least partly, cause the senescence of HECEs. HCECs were cultured using adult human serum instead of bovine serum to get rid of bovine material that can be infected with prions. Primary and passage

  8. Human corneal epithelial subpopulations

    DEFF Research Database (Denmark)

    Søndergaard, Chris Bath

    2013-01-01

    . Since the first successful treatment of LSCD by transplantation of ex vivo expanded LESCs in 1997, many attempts have been carried out to optimize culture conditions to improve the outcome of surgery. To date, progress in this field of bioengineering is substantially hindered by both the lack of...... specific biomarkers of LESCs and the lack of a precise molecular characterization of in situ epithelial subpopulations. The aim of this dissertation was to optimize culture systems with regard to the environmental oxygen concentration for selective ex vivo expansion of LESCs and to analyse in situ...... subpopulations in human corneal epithelium using a combination of laser capture microdissection and RNA sequencing for global transcriptomic profiling. We compared dissociation cultures, using either expansion on γ-irradiated NIH/3T3 feeder cells in serum-rich medium or expansion directly on plastic in serum...

  9. Fuchs' endothelial corneal dystrophy

    DEFF Research Database (Denmark)

    Nielsen, Esben; Ivarsen, Anders; Kristensen, Simon; Hjortdal, Jesper

    2016-01-01

    with normal corneas who received cataract surgery (control group). Subjects were recruited between March 2013 and July 2014. Observational procedures included the following: best-corrected visual acuity (BCVA), contrast sensitivity (CS), Catquest-9SF questionnaire, Scheimpflug tomography and anterior......PURPOSE: To investigate the determining factors of vision and subjective outcome after Descemet's stripping automated endothelial keratoplasty (DSAEK) for Fuchs' endothelial dystrophy (FECD). METHODS: In a prospective study, 41 FECD patients who received DSAEK were compared to 40 cataract patients...... OCT. Examinations were carried out before surgery and at 3-, 6- and 12-month follow-up. Main outcome measures were associations between corneal optics and visual parameters, as well as subjective improvement (Catquest-9SF effect size) RESULTS: Best-corrected visual acuity (BCVA) negatively correlated...

  10. Cornea stress test--evaluation of corneal endothelial function in vivo by contact lens induced stress

    Directory of Open Access Journals (Sweden)

    Saini Jagjit

    1997-01-01

    Full Text Available Reliable and valid assessment of corneal endothelial function is a critical input for diagnosing, prognosticating and monitoring progression of disorders affecting corneal endothelium. In 123 eyes, corneal endothelial function was assessed employing data from the corneal hydration recovery dynamics. Serial pachometric readings were recorded on Haag-Striet pachometer with Mishima-Hedbys modification before and after two hours of thick soft contact lens wear. Percentage Recovery Per Hour (PRPH was derived from raw data as an index of endothelial function. Assessed PRPH in pseudophakic corneal oedema and Fuchs′ endothelial dystrophy eyes (35.9 +/- 9.8% was significantly lower than normal controls (61.9 +/- 10.5%. On employing receiver operation characteristics curve analysis the tested results demonstrated high sensitivity (87% and specificity (92% for detection of low endothelial function at PRPH cut off of 47.5%. Using this PRPH cut off, 80% of Fuchs′ endothelial dystrophy and 93.3% of pseudophakic corneal oedema eyes could be demonstrated to have low endothelial function. A total of 66.7% of diabetic eyes also demonstrated PRPH of lower than 47.5%. Clear corneal grafts demonstrated PRPH values of 24.6% to 73.0%. Of 6 corneal grafts that demonstrated initial PRPH of lower than 47.5%, 4 failed within 4 to 6 months. Our data demonstrated high sensitivity and specificity of this corneal stress test. PRPH index was useful in quantifying endothelial function in clinical disorders including diabetes mellitus. The index PRPH was demonstrated to be useful in monitoring and prognosticating outcome of corneal grafts.

  11. Structure of carbon monoxide time variations in the atmospheric thickness over Central Eurasia (Issyk Kul Monitoring Station)

    Science.gov (United States)

    Aref'ev, V. N.; Kashin, F. V.; Orozaliev, M. D.; Sizov, N. I.; Sinyakov, V. P.; Sorokina, L. I.

    2013-03-01

    The results of measurements of the CO content in the atmospheric thickness by the method of solar molecular-absorption spectroscopy are presented. Over 87 months of observations, the annual mean CO content decreased by ˜19% at a mean rate of changes equal to -(0.14 ± 0.02) atm cm per year. Maxima and minima of seasonal variations most often fall on February and September, respectively. The mean overall amplitude of changes in the CO content during the annual cycle is about 50% of the mean value. The Fourier analysis revealed variations in the CO composition with periods from 3 to 84 months. A simple statistical model satisfactorily describes time changes in the CO content in the atmospheric thickness. The results of measurements of the CO content in the atmospheric thickness are compared with the data of CO measurements in samples of surface air at stations of the Global Atmospheric Watch.

  12. Corneal viscoelastic properties from finite-element analysis of in vivo air-puff deformation.

    Directory of Open Access Journals (Sweden)

    Sabine Kling

    Full Text Available Biomechanical properties are an excellent health marker of biological tissues, however they are challenging to be measured in-vivo. Non-invasive approaches to assess tissue biomechanics have been suggested, but there is a clear need for more accurate techniques for diagnosis, surgical guidance and treatment evaluation. Recently air-puff systems have been developed to study the dynamic tissue response, nevertheless the experimental geometrical observations lack from an analysis that addresses specifically the inherent dynamic properties. In this study a viscoelastic finite element model was built that predicts the experimental corneal deformation response to an air-puff for different conditions. A sensitivity analysis reveals significant contributions to corneal deformation of intraocular pressure and corneal thickness, besides corneal biomechanical properties. The results show the capability of dynamic imaging to reveal inherent biomechanical properties in vivo. Estimates of corneal biomechanical parameters will contribute to the basic understanding of corneal structure, shape and integrity and increase the predictability of corneal surgery.

  13. Cell therapy of congenital corneal diseases with umbilical mesenchymal stem cells: lumican null mice.

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    Hongshan Liu

    Full Text Available BACKGROUND: Keratoplasty is the most effective treatment for corneal blindness, but suboptimal medical conditions and lack of qualified medical personnel and donated cornea often prevent the performance of corneal transplantation in developing countries. Our study aims to develop alternative treatment regimens for congenital corneal diseases of genetic mutation. METHODOLOGY/PRINCIPAL FINDINGS: Human mesenchymal stem cells isolated from neonatal umbilical cords were transplanted to treat thin and cloudy corneas of lumican null mice. Transplantation of umbilical mesenchymal stem cells significantly improved corneal transparency and increased stromal thickness of lumican null mice, but human umbilical hematopoietic stem cells failed to do the same. Further studies revealed that collagen lamellae were re-organized in corneal stroma of lumican null mice after mesenchymal stem cell transplantation. Transplanted umbilical mesenchymal stem cells survived in the mouse corneal stroma for more than 3 months with little or no graft rejection. In addition, these cells assumed a keratocyte phenotype, e.g., dendritic morphology, quiescence, expression of keratocyte unique keratan sulfated keratocan and lumican, and CD34. Moreover, umbilical mesenchymal stem cell transplantation improved host keratocyte functions, which was verified by enhanced expression of keratocan and aldehyde dehydrogenase class 3A1 in lumican null mice. CONCLUSIONS/SIGNIFICANCE: Umbilical mesenchymal stem cell transplantation is a promising treatment for congenital corneal diseases involving keratocyte dysfunction. Unlike donated corneas, umbilical mesenchymal stem cells are easily isolated, expanded, stored, and can be quickly recovered from liquid nitrogen when a patient is in urgent need.

  14. Reconstruction of Rabbit Corneal Layer Composed of Corneal Fibroblasts and Corneal Epithelium on the Lyophilized Amniotic Membrane

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Many researchers have employed the cryopreserved amniotic membrane(CAM) and corneal epithelial cells in the treatment of a severely damaged burned cornea, with corneal epithelial cells cultured on an amniotic membrane (AM). The lyophilized amniotic membrane (LAM) has a higher graft take and a longer shelf life; it is easier to store and safer because of gamma irradiation. Two Teflon rings(Ahn's supporter) were made for culturing the cells on the LAM, and were then used to support the LAM. To reconstruct a corneal layer composed of corneal fibroblasts and epithelium, the corneal fibroblasts were first cultivated on the stromal side of LAM for five days, followed by epithelial cells culture on the epithelial side, by using the air-liquid interface culture. The reconstructed corneal layer composed of corneal fibroblasts and corneal epithelial cells has a much healthier basal layer of corneal epithelium than the reconstructed corneal epithelium, which was got by using only corneal epithelial cells, and resembles the epithelium of normal corneas, without the horny layer. Thus, the reconstruction of the corneal layer by using a LAM is considered to be a good in vitro model, not only for its application in toxicological test kits, but also for transplantation in patients with a severely damaged cornea.

  15. Intrastromal keratoplasy with segment implantation in combination with corneal collagen cross-linking

    Directory of Open Access Journals (Sweden)

    Z.I. Moroz

    2013-03-01

    Full Text Available ABSTRACT Purpose. To evaluate the efficacy of intrastromal keratoplasy with intra-corneal ring segment (ICRS implantation in combination with corneal collagen cross-linking in the treatment of early and advanced keratoconus. Material and methods. In the study 183 eyes with keratoconus were included: 87 eyes (47.5% with the stage II and 96 eyes (32.5% with stage III. The ICRS were implanted as a first step of treatment in 98 cases (53.5%, cross-linking was performed 3 months later. In 85 cases (46.4% the CXL was performed as a first step followed by the ICRS implantation after 3 months. Results. Patients were examined 3, 6, 24 months after surgery. Best functional results were obtained after the ICRS implantation: UCVA and BCVA increased by 3-5 lines, mean keratometry readings decreased by 3.5-4D, the average spherical equivalent decreased by 3.2-2.75D, astigmatism decreased by 2.6-3.9D. After the subsequent CXL procedure, there was a slight improvement of the obtained results. The results obtained in the groups І and II differed insignificantly and were almost identical. At 24 months after surgery some deterioration of functional results was detected in 23.1-26.7% of cases. In the rest of the cases, the obtained effect remained stable. Conclusions. 1. Intra-corneal ring segments implantation and cross-linking are aimed to halt a keratoconus progression and have been successfully used to treat the disease of initial and far-advanced stages. 2. The combination of both methods gives better functional results regardless of which method is performed as a first step. 3. The choice of method to be performed as a first step of treatment depends on the central pachymetry and corneal thickness in a 5-7mm zone of ectasia. 4. Interval between the first and the second step of treatment has to be 3 months or more.

  16. Traumatic corneal endothelial rings from homemade explosives.

    Science.gov (United States)

    Ng, Soo Khai; Rudkin, Adam K; Galanopoulos, Anna

    2013-08-01

    Traumatic corneal endothelial rings are remarkably rare ocular findings that may result from blast injury. We present a unique case of bilateral traumatic corneal endothelial rings secondary to blast injury from homemade explosives. PMID:23474743

  17. Facts about the Cornea and Corneal Disease

    Science.gov (United States)

    ... a donor. This procedure is used for: Fuchs’ dystrophy Post-cataract edema Corneal failure after surgery for cataract, glaucoma or retinal detachment Corneal transplants are generally done under local ...

  18. Proteins of the corneal stroma: importance in visual function.

    Science.gov (United States)

    Xuan, Meng; Wang, Shurong; Liu, Xin; He, Yuxi; Li, Ying; Zhang, Yan

    2016-04-01

    The human cornea, consisting of five layers, is the transparent tissue that refracts and transmits light to the lens and retina, providing about two thirds of the refractive power of the eye. The stroma layer comprises nearly 90 % of the thickness of the cornea and thus plays a pivotal role in normal visual function. The bulk of this layer is constituted by proteins in the extracellular martrix secreted by the corneal epithelial, stroma, and endothelial cells. Clinical research has shown that corneal stroma diseases are common and involve conditions such as infections, injuries, and genetic defects, which cause severe visual disturbances or even blindness. To improve our understanding of the basic molecular mechanisms involved in the physiological and pathological activities of the corneal stroma, its proteins have been brought into the limelight to determine their crucial and irreplaceable roles. The data presented in a previous study have demonstrated the presence of 1679 proteins in the stroma, and this data set has subsequently been perfected by utilizing a highly sensitive isobaric peptide-labeling approach. According to their manifestations, these proteins can be classified as a gel-like organic material composed of proteoglycans, enzymes, and hemocyanin-binding proteins and a network of filaments composed of collagen, elastin, keratin, vimentin, and interconnected filaments comprising fibronectin and laminin. The aim of this review is to describe some corneal stroma proteins by highlighting their major functions and valuable applications in ophthalmologic research toward the better characterization and treatment of eye diseases. PMID:26905288

  19. MicroRNA-145 regulates human corneal epithelial differentiation.

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    Sharon Ka-Wai Lee

    Full Text Available BACKGROUND: Epigenetic factors, such as microRNAs, are important regulators in the self-renewal and differentiation of stem cells and progenies. Here we investigated the microRNAs expressed in human limbal-peripheral corneal (LPC epithelia containing corneal epithelial progenitor cells (CEPCs and early transit amplifying cells, and their role in corneal epithelium. METHODOLOGY/PRINCIPAL FINDINGS: Human LPC epithelia was extracted for small RNAs or dissociated for CEPC culture. By Agilent Human microRNA Microarray V2 platform and GeneSpring GX11.0 analysis, we found differential expression of 18 microRNAs against central corneal (CC epithelia, which were devoid of CEPCs. Among them, miR-184 was up-regulated in CC epithelia, similar to reported finding. Cluster miR-143/145 was expressed strongly in LPC but weakly in CC epithelia (P = 0.0004, Mann-Whitney U-test. This was validated by quantitative polymerase chain reaction (qPCR. Locked nucleic acid-based in situ hybridization on corneal rim cryosections showed miR-143/145 presence localized to the parabasal cells of limbal epithelium but negligible in basal and superficial epithelia. With holoclone forming ability, CEPCs transfected with lentiviral plasmid containing mature miR-145 sequence gave rise to defective epithelium in organotypic culture and had increased cytokeratin-3/12 and connexin-43 expressions and decreased ABCG2 and p63 compared with cells transfected with scrambled sequences. Global gene expression was analyzed using Agilent Whole Human Genome Oligo Microarray and GeneSpring GX11.0. With a 5-fold difference compared to cells with scrambled sequences, miR-145 up-regulated 324 genes (containing genes for immune response and down-regulated 277 genes (containing genes for epithelial development and stem cell maintenance. As validated by qPCR and luciferase reporter assay, our results showed miR-145 suppressed integrin β8 (ITGB8 expression in both human corneal epithelial cells

  20. Management of pediatric corneal limbal dermoids.

    Science.gov (United States)

    Pirouzian, Amir

    2013-01-01

    This paper reviews the data in the published literature (PubMed from 1937 to 2011) concerning the medical and surgical management of pediatric limbal dermoids. Current standard medical treatment for grade I pediatric limbal dermoids (ie, with superficial corneal involvment) is initially conservative. In stages II (ie, affecting the full thickness of the cornea with/without endothelial involvement) and III (ie, involvement of entire cornea and anterior chamber), a combination of excision, lamellar keratoplasty, and amniotic membrane and limbal stem cell tranplantation are advocated. Combinations of these approaches seem to yield better and more stable long-term ocular surface cosmesis and fewer complications in comparison with traditional methods of excision and lamellar keratoplasty. Management of amblyopia (i.e. occlusion treatment, chemical penalization with/without spectacle wear, etc) must continue after surgical excision to yield optimal results when or if the surgery is done at a younger age. PMID:23576860

  1. Bilateral Keratectasia 34 Years after Corneal Transplant

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    Xavier Valldeperas

    2010-07-01

    Full Text Available We report the clinical findings of a patient with severe bilateral keratectasia 34 years after a penetrating keratoplasty (PK in both eyes. An otherwise healthy 67-year-old man complained of deterioration of the eyesight in both eyes over the last 6 months. The patient was diagnosed with bilateral keratoconus at the age of 32 years, and he underwent a bilateral PK. At presentation, visual acuity was 20/200 in the right eye and light perception in the left eye. A Pentacam pachymetric map revealed a central pachymetry of 720 µm in the right eye and of 710 µm in the left eye, as well as an average paracentral pachymetry of 436 and 270 µm in the 9-mm zone in the right and the left eye, respectively. Corneal topography revealed bilateral irregular and asymmetric bowing with generalized steepening and high corneal power. We describe a case of bilateral keratectasia 34 years after PK in a patient who was originally diagnosed with bilateral keratoconus.

  2. Acute corneal hydrops in keratoconus

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    Prafulla K Maharana

    2013-01-01

    Full Text Available Acute corneal hydrops is a condition characterized by stromal edema due to leakage of aqueous through a tear in descemet membrane. The patient presents with sudden onset decrease in vision, photophobia, and pain. Corneal thinning and ectasias combined with trivial trauma to the eye mostly by eye rubbing is considered as the underlying cause. With conservative approach self-resolution takes around 2 to 3 months. Surgical intervention is required in cases of non-resolution of corneal edema to avoid complications and for early visual rehabilitation. Intracameral injection of air or gas such as perflouropropane is the most common surgical procedure done. Recent investigative modality such as anterior segment optical coherence tomography is an extremely useful tool for diagnosis, surgical planning, and postoperative follow up. Resolution of hydrops may improve the contact lens tolerance and visual acuity but most cases require keratoplasty for visual rehabilitation.

  3. Progress in corneal wound healing.

    Science.gov (United States)

    Ljubimov, Alexander V; Saghizadeh, Mehrnoosh

    2015-11-01

    Corneal wound healing is a complex process involving cell death, migration, proliferation, differentiation, and extracellular matrix remodeling. Many similarities are observed in the healing processes of corneal epithelial, stromal and endothelial cells, as well as cell-specific differences. Corneal epithelial healing largely depends on limbal stem cells and remodeling of the basement membrane. During stromal healing, keratocytes get transformed to motile and contractile myofibroblasts largely due to activation of transforming growth factor-β (TGF-β) system. Endothelial cells heal mostly by migration and spreading, with cell proliferation playing a secondary role. In the last decade, many aspects of wound healing process in different parts of the cornea have been elucidated, and some new therapeutic approaches have emerged. The concept of limbal stem cells received rigorous experimental corroboration, with new markers uncovered and new treatment options including gene and microRNA therapy tested in experimental systems. Transplantation of limbal stem cell-enriched cultures for efficient re-epithelialization in stem cell deficiency and corneal injuries has become reality in clinical setting. Mediators and course of events during stromal healing have been detailed, and new treatment regimens including gene (decorin) and stem cell therapy for excessive healing have been designed. This is a very important advance given the popularity of various refractive surgeries entailing stromal wound healing. Successful surgical ways of replacing the diseased endothelium have been clinically tested, and new approaches to accelerate endothelial healing and suppress endothelial-mesenchymal transformation have been proposed including Rho kinase (ROCK) inhibitor eye drops and gene therapy to activate TGF-β inhibitor SMAD7. Promising new technologies with potential for corneal wound healing manipulation including microRNA, induced pluripotent stem cells to generate corneal

  4. Collagens and proteoglycans of the corneal extracellular matrix

    Directory of Open Access Journals (Sweden)

    Y.M. Michelacci

    2003-08-01

    Full Text Available The cornea is a curved and transparent structure that provides the initial focusing of a light image into the eye. It consists of a central stroma that constitutes 90% of the corneal depth, covered anteriorly with epithelium and posteriorly with endothelium. Its transparency is the result of the regular spacing of collagen fibers with remarkably uniform diameter and interfibrillar space. Corneal collagen is composed of heterotypic fibrils consisting of type I and type V collagen molecules. The cornea also contains unusually high amounts of type VI collagen, which form microfibrillar structures, FACIT collagens (XII and XIV, and other nonfibrillar collagens (XIII and XVIII. FACIT collagens and other molecules, such as leucine-rich repeat proteoglycans, play important roles in modifying the structure and function of collagen fibrils.Proteoglycans are macromolecules composed of a protein core with covalently linked glycosaminoglycan side chains. Four leucine-rich repeat proteoglycans are present in the extracellular matrix of corneal stroma: decorin, lumican, mimecan and keratocan. The first is a dermatan sulfate proteoglycan, and the other three are keratan sulfate proteoglycans. Experimental evidence indicates that the keratan sulfate proteoglycans are involved in the regulation of collagen fibril diameter, and dermatan sulfate proteoglycan participates in the control of interfibrillar spacing and in the lamellar adhesion properties of corneal collagens. Heparan sulfate proteoglycans are minor components of the cornea, and are synthesized mainly by epithelial cells. The effect of injuries on proteoglycan synthesis is discussed.

  5. Fate Mapping Mammalian Corneal Epithelia.

    Science.gov (United States)

    Richardson, Alexander; Wakefield, Denis; Di Girolamo, Nick

    2016-04-01

    The anterior aspect of the cornea consists of a stratified squamous epithelium, thought to be maintained by a rare population of stem cells (SCs) that reside in the limbal transition zone. Although migration of cells that replenish the corneal epithelium has been studied for over a century, the process is still poorly understood and not well characterized. Numerous techniques have been employed to examine corneal epithelial dynamics, including visualization by light microscopy, the incorporation of vital dyes and DNA labels, and transplantation of genetically marked cells that have acted as cell and lineage beacons. Modern-day lineage tracing utilizes molecular methods to determine the fate of a specific cell and its progeny over time. Classically employed in developmental biology, lineage tracing has been used more recently to track the progeny of adult SCs in a number of organs to pin-point their location and understand their movement and influence on tissue regeneration. This review highlights key discoveries that have led researchers to develop cutting-edge genetic tools to effectively and more accurately monitor turnover and displacement of cells within the mammalian corneal epithelium. Collating information on the basic biology of SCs will have clinical ramifications in furthering our knowledge of the processes that govern their role in homeostasis, wound-healing, transplantation, and how we can improve current unsatisfactory SC-based therapies for patients suffering blinding corneal disease. PMID:26774909

  6. [Current treatments for corneal neovascularization].

    Science.gov (United States)

    Benayoun, Y; Petellat, F; Leclerc, O; Dost, L; Dallaudière, B; Reddy, C; Robert, P-Y; Salomon, J-L

    2015-12-01

    The extension of blood vessels into the normally avascular stroma defines corneal neovascularization. Though this phenomenon, pathophysiological and clinical features are well characterized, therapeutic modalities have been hindered by a lack of safe, efficacious and non-controversial treatments. In this literature review, we focus on available therapeutic options in light of recent evidence provided by animal and clinical studies. First, this review will focus on pharmacological treatments that target angiogenesis. The low cost and market availability of bevacizumab make it the first anti-angiogenic therapy choice, and it has demonstrable efficacy in reducing corneal neovascularization when administered topically or subconjunctivally. However, novel anti-angiogenic molecules targeting the intracellular pathways of angiogenesis (siRNA, antisense oligonucleotides) provide a promising alternative. Laser therapy (direct photocoagulation or photo-dynamic therapy) and fine needle diathermy also find a place in the treatment of stabilized corneal neovascularization alone or in association with anti-angiogenic therapy. Additionally, ocular surface reconstruction using amniotic membrane graft or limbal stem cell transplantation is essential when corneal neovascularization is secondary to primary or acquired limbal deficiency. PMID:26522890

  7. Corneal stroma microfibrils

    KAUST Repository

    Hanlon, Samuel D.

    2015-03-01

    Elastic tissue was first described well over a hundred years ago and has since been identified in nearly every part of the body. In this review, we examine elastic tissue in the corneal stroma with some mention of other ocular structures which have been more thoroughly described in the past. True elastic fibers consist of an elastin core surrounded by fibrillin microfibrils. However, the presence of elastin fibers is not a requirement and some elastic tissue is comprised of non-elastin-containing bundles of microfibrils. Fibers containing a higher relative amount of elastin are associated with greater elasticity and those without elastin, with structural support. Recently it has been shown that the microfibrils, not only serve mechanical roles, but are also involved in cell signaling through force transduction and the release of TGF-β. A well characterized example of elastin-free microfibril bundles (EFMBs) is found in the ciliary zonules which suspend the crystalline lens in the eye. Through contraction of the ciliary muscle they exert enough force to reshape the lens and thereby change its focal point. It is believed that the molecules comprising these fibers do not turn-over and yet retain their tensile strength for the life of the animal. The mechanical properties of the cornea (strength, elasticity, resiliency) would suggest that EFMBs are present there as well. However, many authors have reported that, although present during embryonic and early postnatal development, EFMBs are generally not present in adults. Serial-block-face imaging with a scanning electron microscope enabled 3D reconstruction of elements in murine corneas. Among these elements were found fibers that formed an extensive network throughout the cornea. In single sections these fibers appeared as electron dense patches. Transmission electron microscopy provided additional detail of these patches and showed them to be composed of fibrils (~10nm diameter). Immunogold evidence clearly

  8. Corneal topographic changes after 20-gauge pars plana vitrectomy associated with scleral buckling for the treatment of rhegmatogenous retinal detachment

    Directory of Open Access Journals (Sweden)

    Alexandre Achille Grandinetti

    2013-04-01

    Full Text Available PURPOSE: To evaluate the changes in corneal topography after 20-gauge pars plana vitrectomy associated with scleral buckling for the repair of rhegmatogenous retinal detachment. METHODS: Twenty-five eyes of 25 patients with rhegmatogenous retinal detachment were included in this study. 20-gauge pars plana vitrectomy associated with scleral buckling was performed in all patients. The corneal topography of each was measured before surgery and one week, one month, and three months after surgery by computer-assisted videokeratoscopy. RESULTS: A statistically significant central corneal steepening (average, 0,9 D , p<0,001 was noted one week after surgery. The total corneal astigmatism had a significant increase in the first postoperative month (p=0,007. All these topographic changes persisted for the first month but returned to preoperative values three months after the surgery. CONCLUSION: Pars plana vitrectomy with scleral buckling was found to induce transient changes in corneal topography.

  9. Management of corneal bee sting

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    Razmjoo H

    2011-12-01

    Full Text Available Hassan Razmjoo1,2, Mohammad-Ali Abtahi1,2,4, Peyman Roomizadeh1,3, Zahra Mohammadi1,2, Seyed-Hossein Abtahi1,3,41Medical School, Isfahan University of Medical Sciences (IUMS; 2Ophthalmology Ward, Feiz Hospital, IUMS; 3Isfahan Medical Students Research Center (IMSRC, IUMS; 4Isfahan Ophthalmology Research Center (IORC, Feiz Hospital, IUMS, Isfahan, IranAbstract: Corneal bee sting is an uncommon environmental eye injury that can result in various ocular complications with an etiology of penetrating, immunologic, and toxic effects of the stinger and its injected venom. In this study we present our experience in the management of a middle-aged male with a right-sided deep corneal bee sting. On arrival, the patient was complaining of severe pain, blurry vision with acuity of 160/200, and tearing, which he had experienced soon after the injury. Firstly, we administered conventional drugs for eye injuries, including topical antibiotic, corticosteroid, and cycloplegic agents. After 2 days, corneal stromal infiltration and edema developed around the site of the sting, and visual acuity decreased to 100/200. These conditions led us to remove the stinger surgically. Within 25 days of follow-up, the corneal infiltration decreased gradually, and visual acuity improved to 180/200. We suggest a two-stage management approach for cases of corneal sting. For the first stage, if the stinger is readily accessible or primary dramatic reactions, including infiltration, especially on the visual axis, exist, manual or surgical removal would be indicated. Otherwise, we recommend conventional treatments for eye injuries. Given this situation, patients should be closely monitored for detection of any worsening. If the condition does not resolve or even deteriorates, for the second stage, surgical removal of the stinger under local or generalized anesthesia is indicated.Keywords: bee sting, stinger, cornea, removal, management, surgery

  10. Keratopathy due to ophthalmic drug abuse with corneal melting and perforation presenting as Mooren-like ulcer: A case report

    Science.gov (United States)

    WU, HUI; HU, YUAN; SHI, XIAO-RU; XU, FEIHONG; JIANG, CHUN-YING; HUANG, RONG; JIA, HUI

    2016-01-01

    The present report describes the clinical course and treatment of a Mooren-like ulcer associated with abuse of topical anesthetics and dexamethasone. A 38-year-old male physician treated himself with lidocaine, tetracaine and dexamethasone (DEX) eye drops for severe pain and decline of vision in both eyes. After six months of treatment, his right cornea exhibited annular melting with full-thickness stromal infiltration at the limbus and central corneal haze. His left cornea was completely melted and exhibited iris prolapse. The patient was treated with topical antibiotics, lubricants and underwent a binocular keratoplasty. The surgery was successful and after eight months the postoperative best-corrected visual acuities were counting fingers in the right eye and light perception in the left eye. In summary, this report documents a severe case of keratopathy presenting as Mooren-like ulcer caused by topical anesthetics and DEX, which were treated via keratoplasty, resulting in useful vision being retained.

  11. The effect of 193 nm excimer laser radiation on the human corneal endothelial cell density

    International Nuclear Information System (INIS)

    The effect of 193 nm excimer laser radiation on human corneal endothelial cell density was examined. Fifty-five eyes from 35 patients underwent photorefractive keratectomy for myopia. Photomicrographs of the endothelium were taken a short time before the operation and on an average of 7 months postoperatively with a specular microscope. The average endothelial cell densities were preoperatively 3375 ± 266 cells/mm2 (means ± SD) and postoperatively 3348 ± 287 cells/mm2, corresponding to a fall of 27 cells/mm2 (N = 55). This fall in endothelial cell density was not statistically significant. A significant correlation between the change in cell density and age of the patient was found, with older patients losing more cells (N = 35, 2p < 0.05). The magnification of the specular microscope was found to change with corneal thickness. The importance of correcting the endothelial cell densities for corneal thickness is discussed. (au) 14 refs

  12. The effect of 193 nm excimer laser radiation on the human corneal endothelial cell density

    Energy Technology Data Exchange (ETDEWEB)

    Isager, P.; Hjortdal, J.Oe.; Ehlers, N. [Aarhus Univ. Hospital, Dept. of Ophthalmology, Aarhus (Denmark)

    1996-06-01

    The effect of 193 nm excimer laser radiation on human corneal endothelial cell density was examined. Fifty-five eyes from 35 patients underwent photorefractive keratectomy for myopia. Photomicrographs of the endothelium were taken a short time before the operation and on an average of 7 months postoperatively with a specular microscope. The average endothelial cell densities were preoperatively 3375 {+-} 266 cells/mm{sup 2} (means {+-} SD) and postoperatively 3348 {+-} 287 cells/mm{sup 2}, corresponding to a fall of 27 cells/mm{sup 2} (N = 55). This fall in endothelial cell density was not statistically significant. A significant correlation between the change in cell density and age of the patient was found, with older patients losing more cells (N = 35, 2p < 0.05). The magnification of the specular microscope was found to change with corneal thickness. The importance of correcting the endothelial cell densities for corneal thickness is discussed. (au) 14 refs.

  13. Get It through Your Thick Head: Emerging Principles in Neuroimmunology and Neurovirology Redefine Central Nervous System "Immune Privilege".

    Science.gov (United States)

    Solomos, Andreas C; Rall, Glenn F

    2016-04-20

    The central nervous system (CNS) coordinates all aspects of life, autonomic and sentient, though how it has evolved to contend with pathogenic infections remains, to a great degree, a mystery. The skull and cerebrospinal fluid (CSF) provide protection from blunt force contacts, and it was once thought that the blood-brain barrier (BBB) was a fortress that restricted pathogen entry and limited inflammation. Recent studies, however, have caused a revision of this viewpoint: the CNS is monitored by blood-borne lymphocytes, but can use alternative strategies to prevent or resolve many pathogenic challenges. In this Review, we discuss emerging principles that indicate how the CNS is immunologically unique from peripheral tissues. We focus on developments that include glymphatics, recently characterized brain lymphatic vessels, distinctions in innate and adaptive immune strategies, novel points of entry for neurotropic viruses, and, finally, how the periphery can influence CNS homeostasis and immune responses within the brain. Collectively, these attributes demand a re-evaluation of immunity in the brain: not privileged, but distinct. PMID:26854733

  14. Turning the tide of corneal blindness

    Directory of Open Access Journals (Sweden)

    Matthew S Oliva

    2012-01-01

    Full Text Available Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world′s largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind.

  15. Turning the tide of corneal blindness.

    Science.gov (United States)

    Oliva, Matthew S; Schottman, Tim; Gulati, Manoj

    2012-01-01

    Corneal diseases represent the second leading cause of blindness in most developing world countries. Worldwide, major investments in public health infrastructure and primary eye care services have built a strong foundation for preventing future corneal blindness. However, there are an estimated 4.9 million bilaterally corneal blind persons worldwide who could potentially have their sight restored through corneal transplantation. Traditionally, barriers to increased corneal transplantation have been daunting, with limited tissue availability and lack of trained corneal surgeons making widespread keratoplasty services cost prohibitive and logistically unfeasible. The ascendancy of cataract surgical rates and more robust eye care infrastructure of several Asian and African countries now provide a solid base from which to dramatically expand corneal transplantation rates. India emerges as a clear global priority as it has the world's largest corneal blind population and strong infrastructural readiness to rapidly scale its keratoplasty numbers. Technological modernization of the eye bank infrastructure must follow suit. Two key factors are the development of professional eye bank managers and the establishment of Hospital Cornea Recovery Programs. Recent adaptation of these modern eye banking models in India have led to corresponding high growth rates in the procurement of transplantable tissues, improved utilization rates, operating efficiency realization, and increased financial sustainability. The widespread adaptation of lamellar keratoplasty techniques also holds promise to improve corneal transplant success rates. The global ophthalmic community is now poised to scale up widespread access to corneal transplantation to meet the needs of the millions who are currently blind. PMID:22944753

  16. PAIRED OPPOSITE CLEAR CORNEAL INCISIONS TO REDUCE PREEXISTING CORNEAL ASTIGMATISM IN PHACOEMULSIFICATION

    OpenAIRE

    Chandrakant; Narayan; Srinivasulu; Prabhu; Inchara; Sushma; Padmini

    2015-01-01

    BACKGROUND: To study the effect of paired opposite clear corneal incisions on the steep axis on preexisting corneal astigmatism in phacoemulsification. MATERIALS AND METHODS : This study was performed on 30 eyes of 30 patients who had keratometric astigmatism of more than 1 diopter. All patients underwent clear corneal phacoemulsification with a 3.2mm clear corneal incision on the stee p axis. An additional similar incision was placed on the steep axis opposit...

  17. Pterygium-induced corneal refractive changes

    Directory of Open Access Journals (Sweden)

    Maheshwari Sejal

    2007-01-01

    Full Text Available To study the effect of pterygium on corneal topography, a retrospective analysis of 151 eyes with primary pterygia was done. All cases underwent videokeratography preoperatively and one month postoperatively. Statistical analysis of average corneal power (ACP, corneal astigmatism, surface regularity index (SRI and surface asymmetry index (SAI was done before and one month after surgery. Topographic indices were compared statistically for various grades of pterygia. Increase in the grade of pterygia had a significant effect on topographic indices. Corneal astigmatism reduced from 4.40±3.64 diopter (D to 1.55±1.63D ( P value < 0.001 following surgery. The regularity of corneal surface improved and asymmetry of the cornea reduced one month after surgery. Pterygium leads to significant changes in corneal refractive status, which increase with the increase in the grade of pterygia and improve following pterygium excision.

  18. Geometry and kinematics of the Andean thick-skinned thrust systems: Insights from the Chilean Frontal Cordillera (28°-28.5°S), Central Andes

    Science.gov (United States)

    Martínez, F.; Arriagada, C.; Valdivia, R.; Deckart, K.; Peña, M.

    2015-12-01

    The structure of the Chilean Frontal Cordillera, located over the Central Andes flat-slab subduction segment (27°-28.5°S), is characterized by a thick-skinned deformation, affecting both the pre-rift basement and the Mesozoic and Cenozoic infill of the NNE-SSW Lautaro and Lagunillas Basins, which were developed during the Pangea-Gondwana break-up. The compressive deformation show a complex interaction between Mesozoic rift structures and thrust systems, affecting a suite of Permo-Triassic (258-245 Ma) granitic blocks. We used a combination of geological mapping, new structural data, balanced and restored cross sections and geochronological data to investigate the geometry and kinematics of the Andean thick-skinned thrust systems of the region. The thrust systems include double-vergent thick-skinned thrust faults, basement-cored anticlines and minor thin-skinned thrusts and folds. The presence of Triassic and Jurassic syn-rift successions along the hanging wall and footwall of the basement thrust faults are keys to suggest that the current structural framework of the region should be associated with the shortening of previous Mesozoic half grabens. Based on this interpretation, we propose a deformation mechanism characterized by the tectonic inversion of rift-related faults and the propagation of basement ramps that fold and cut both, the early normal faults and the basement highs. New U-Pb ages obtained from synorogenic deposits (Quebrada Seca and Doña Ana formations) indicate at least three important compressive pulses. A first pulse at ˜80 Ma (Late Cretaceous), a second pulse related to the K-T phase of Andean deformation and, finally, a third pulse that occurred during the lower Miocene.

  19. Development and Beam-Shape Analysis of an Integrated Fiber-Optic Confocal Probe for High-Precision Central Thickness Measurement of Small-Radius Lenses

    Directory of Open Access Journals (Sweden)

    Boonsong Sutapun

    2015-04-01

    Full Text Available This work describes a new design of a fiber-optic confocal probe suitable for measuring the central thicknesses of small-radius optical lenses or similar objects. The proposed confocal probe utilizes an integrated camera that functions as a shape-encoded position-sensing device. The confocal signal for thickness measurement and beam-shape data for off-axis measurement can be simultaneously acquired using the proposed probe. Placing the probe’s focal point off-center relative to a sample’s vertex produces a non-circular image at the camera’s image plane that closely resembles an ellipse for small displacements. We were able to precisely position the confocal probe’s focal point relative to the vertex point of a ball lens with a radius of 2.5 mm, with a lateral resolution of 1.2 µm. The reflected beam shape based on partial blocking by an aperture was analyzed and verified experimentally. The proposed confocal probe offers a low-cost, high-precision technique, an alternative to a high-cost three-dimensional surface profiler, for tight quality control of small optical lenses during the manufacturing process.

  20. MICROBIOLOGICAL STUDY OF CORNEAL ULCERS AT KIMS, AMALAPURAM

    Directory of Open Access Journals (Sweden)

    Padmaja

    2014-04-01

    Full Text Available Corneal ulcers are the common cause of corneal blindness. Of the corneal ulcers, majority of the cases are because of the fungal etiology. The present study is aimed to identify the pathogenic organisms responsible for corneal infections. Majority of the cases are secondary to trauma. Of the fungal cases, Aspergillus is found to be the predominant fungus affecting corneal ulcers, followed by bacteria affecting the corneal ulcers.

  1. Pterygium-induced corneal refractive changes

    OpenAIRE

    Maheshwari Sejal

    2007-01-01

    To study the effect of pterygium on corneal topography, a retrospective analysis of 151 eyes with primary pterygia was done. All cases underwent videokeratography preoperatively and one month postoperatively. Statistical analysis of average corneal power (ACP), corneal astigmatism, surface regularity index (SRI) and surface asymmetry index (SAI) was done before and one month after surgery. Topographic indices were compared statistically for various grades of pterygia. Increase in the grade of...

  2. Glaucoma and Corneal Transplant Procedures

    Directory of Open Access Journals (Sweden)

    Ammar M. Al-Mahmood

    2012-01-01

    Full Text Available Glaucoma after corneal transplantation is a leading cause of ocular morbidity after penetrating keratoplasty. The incidence reported is highly variable and a number of etiologic factors have been identified. A number of treatment options are available; surgical intervention for IOP control is associated with a high incidence of graft failure. IOP elevation is less frequently seen following deep anterior lamellar keratoplasty. Descemet's striping-automated endothelial keratoplasty is also associated with postprocedure intraocular pressure elevation and secondary glaucoma and presents unique surgical challenges in patients with preexisting glaucoma surgeries. Glaucoma exists in up to three-quarters of patients who undergo keratoprosthesis surgery and the management if often challenging. The aim of this paper is to highlight the incidence, etiology, and management of glaucoma following different corneal transplant procedures. It also focuses on the challenges in the diagnosis of glaucoma and intraocular pressure monitoring in this group of patients.

  3. Inverse Cutting of Posterior Lamellar Corneal Grafts by a Femtosecond Laser

    DEFF Research Database (Denmark)

    Hjortdal, Jesper; Nielsen, Esben; Vestergaard, Anders;

    2012-01-01

    (range: 1.400 to 2.000 cells per sq. mm). The grafts were of uniform thickness, but substantial interface haze was present in most grafts. Conclusions: Posterior lamellar corneal grafts can be prepared from the endothelial side using a femto-second laser. All grafts were clear after 6 months with...

  4. Mapping distribution and thickness of supraglacial debris in the Central Karakoram National Park: main features and implications to model glacier meltwater

    Science.gov (United States)

    Minora, Umberto; Mayer, Christoph; Bocchiola, Daniele; D'Agata, Carlo; Maragno, Davide; Lambrecht, Astrid; Vuillermoz, Elisa; smiraglia, claudio; diolaiuti, guglielmina

    2014-05-01

    Supraglacial debris plays a not negligible role in controlling magnitude and rates of buried ice melt (Østrem, 1959; Mattson et al., 1993). Knowledge on rock debris is essential to model ice melt (and consequently meltwater discharge) upon wide glacierized areas, as melt rates are mainly driven by debris thickness variability. This is particularly important for the Pamir-Himalaya-Karakoram area (PHK), where debris-covered glaciers are frequent (Smiraglia et al., 2007; Scherler et al., 2011) and where melt water from glaciers supports agriculture and hydropower production. By means of remote sensing techniques and field data, supraglacial debris can be detected, and then quantified in area and thickness. Supervised classifications of satellite imagery can be used to map debris on glaciers. They use different algorithms to cluster an image based on its pixel values, and Region Of Interests (ROIs) previously selected by the human operator. This can be used to obtain a supraglacial debris mask by which surface extension can be calculated. Moreover, kinetic surface temperature data derived from satellites (such as ASTER and Landsat), can be used to quantify debris thicknesses (Mihalcea et al., 2008). Ground Control Points (GCPs) are essential to validate the obtained debris thicknesses. We took the Central Karakoram National Park (CKNP) as a representative sample for PHK area. The CKNP is 12,000 km2 wide, with more than 700 glaciers, mostly debris covered (Minora et al., 2013). Among those we find some of the widest glaciers of the World (e.g: Baltoro). To improve the knowledge on these glaciers and to better model their melt and water discharge we proceeded as follows. Firstly we ran a Supervised Maximum Likelihood (SML) classification on 2001 and 2010 Landsat images to detect debris presence and distribution. Secondly we analyzed kinetic surface temperature (from Landsat) to map debris depth. This latter attempt took also advantage from field data of debris thickness

  5. Reliability of corneal dynamic scheimpflug analyser measurements in virgin and post-PRK eyes.

    Directory of Open Access Journals (Sweden)

    Xiangjun Chen

    Full Text Available PURPOSE: To determine the measurement reliability of CorVis ST, a dynamic Scheimpflug analyser, in virgin and post-photorefractive keratectomy (PRK eyes and compare the results between these two groups. METHODS: Forty virgin eyes and 42 post-PRK eyes underwent CorVis ST measurements performed by two technicians. Repeatability was evaluated by comparing three consecutive measurements by technician A. Reproducibility was determined by comparing the first measurement by technician A with one performed by technician B. Intraobserver and interobserver intraclass correlation coefficients (ICCs were calculated. Univariate analysis of covariance (ANCOVA was used to compare measured parameters between virgin and post-PRK eyes. RESULTS: The intraocular pressure (IOP, central corneal thickness (CCT and 1st applanation time demonstrated good intraobserver repeatability and interobserver reproducibility (ICC ≧ 0.90 in virgin and post-PRK eyes. The deformation amplitude showed a good or close to good repeatability and reproducibility in both groups (ICC ≧ 0.88. The CCT correlated positively with 1st applanation time (r = 0.437 and 0.483, respectively, p<0.05 and negatively with deformation amplitude (r = -0.384 and -0.375, respectively, p<0.05 in both groups. Compared to post-PRK eyes, virgin eyes showed longer 1st applanation time (7.29 ± 0.21 vs. 6.96 ± 0.17 ms, p<0.05 and lower deformation amplitude (1.06 ± 0.07 vs. 1.17 ± 0.08 mm, p < 0.05. CONCLUSIONS: CorVis ST demonstrated reliable measurements for CCT, IOP, and 1st applanation time, as well as relatively reliable measurement for deformation amplitude in both virgin and post-PRK eyes. There were differences in 1st applanation time and deformation amplitude between virgin and post-PRK eyes, which may reflect corneal biomechanical changes occurring after the surgery in the latter.

  6. Optimization model for UV-Riboflavin corneal cross-linking

    Science.gov (United States)

    Schumacher, S.; Wernli, J.; Scherrer, S.; Bueehler, M.; Seiler, T.; Mrochen, M.

    2011-03-01

    Nowadays UV-cross-linking is an established method for the treatment of keraectasia. Currently a standardized protocol is used for the cross-linking treatment. We will now present a theoretical model which predicts the number of induced crosslinks in the corneal tissue, in dependence of the Riboflavin concentration, the radiation intensity, the pre-treatment time and the treatment time. The model is developed by merging the difussion equation, the equation for the light distribution in dependence on the absorbers in the tissue and a rate equation for the polymerization process. A higher concentration of Riboflavin solution as well as a higher irradiation intensity will increase the number of induced crosslinks. However, performed stress-strain experiments which support the model showed that higher Riboflavin concentrations (> 0.125%) do not result in a further increase in stability of the corneal tissue. This is caused by the inhomogeneous distribution of induced crosslinks throughout the cornea due to the uneven absorption of the UV-light. The new model offers the possibility to optimize the treatment individually for every patient depending on their corneal thickness in terms of efficiency, saftey and treatment time.

  7. Ultrastructural analysis of corneal exposure to UV radiation

    International Nuclear Information System (INIS)

    The primate cornea was exposed to 300 nm UVR with five levels of radiant expsure from 0.08 to 0.6 Jcm-2. All cellular layers of the cornea were damaged at the 0.08 Jcm-2 exposure, and damage became more severe as the exposure level was increased. The corneal cells showed variable response in that essentially normal cells were found among damaged cells. Eight days post-exposure using the 0.6 Jcm-2 level, the epithelium had regained its normal thickness and was populated largely by normal appearing cells; however, the stroma showed damaged keratocytes and the loss of keratocytes. The corneal basement membranes (the epithelial basement membrane and the posterior limiting lamina) and the anterior limiting lamina were not damaged at any exposure level except for an isolated area along the epithelial basement membrane in one cornea. Therefore, one is lead to conclude that basement membranes are unaffected by UVR. The endothelium continued to demonstrate the loss of mitochondria, endoplasmic reticulum and some vacuoles at 8 days after exposure. However, the endothelium appeared to have resumed its physiological function as demonstrated by the reduced stromal oedema. This research gives the first complete description of UV-B induced corneal damage and repair of the full, in-depth cornea of the primate using the EM. (author)

  8. Transparent, resilient human amniotic membrane laminates for corneal transplantation.

    Science.gov (United States)

    Hariya, Takehiro; Tanaka, Yuji; Yokokura, Shunji; Nakazawa, Toru

    2016-09-01

    This study evaluated a new technique to toughen and optically clarify human amniotic membrane (AM) tissue, which is naturally thin and clouded, and determined the suitability of the altered tissue for corneal transplantation. The technique created a tissue laminate by repeatedly depositing wet layers of AM and dehydrating them, followed by chemical cross-linking to tighten integration at the layer interfaces and within the layers, thereby improving the physical properties of the laminates by increasing light transmittance and mechanical strength. Interestingly, this improvement only occurred in laminates with at least 4 layers. Cross-linking also improved the resistance of the laminates to collagenase degradation, such as occurs in corneal melting. This study also confirmed that the AM tissue was biocompatible by inserting AM monolayers into the corneal stroma of rabbits, and by performing lamellar keratoplasty in rabbits with cross-linked AM laminates. The laminates were sufficiently thick and resilient to need only one set of sutures, whereas in previously described multi-layer AM transplantation technique, each layer required separate sutures. The current findings are a promising advance in the engineering of novel biomaterials and the alteration of existing tissues for medical use. PMID:27267629

  9. Ultrastructural analysis of corneal exposure to UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pitts, D.G.; Bergmanson, J.P.G.; Chu, L.W.-F.

    1987-01-01

    The primate cornea was exposed to 300 nm UVR with five levels of radiant expsure from 0.08 to 0.6 Jcm/sup -2/. All cellular layers of the cornea were damaged at the 0.08 Jcm/sup -2/ exposure, and damage became more severe as the exposure level was increased. The corneal cells showed variable response in that essentially normal cells were found among damaged cells. Eight days post-exposure using the 0.6 Jcm/sup -2/ level, the epithelium had regained its normal thickness and was populated largely by normal appearing cells; however, the stroma showed damaged keratocytes and the loss of keratocytes. The corneal basement membranes (the epithelial basement membrane and the posterior limiting lamina) and the anterior limiting lamina were not damaged at any exposure level except for an isolated area along the epithelial basement membrane in one cornea. Therefore, one is lead to conclude that basement membranes are unaffected by UVR. The endothelium continued to demonstrate the loss of mitochondria, endoplasmic reticulum and some vacuoles at 8 days after exposure. However, the endothelium appeared to have resumed its physiological function as demonstrated by the reduced stromal oedema. This research gives the first complete description of UV-B induced corneal damage and repair of the full, in-depth cornea of the primate using the EM.

  10. System for quantifying the formation stages of corneal arcus

    Science.gov (United States)

    Nasution, Aulia; Fahdarina, Sally; Cahya, Deny I.

    2015-07-01

    Extensive research on interpreting the clinical signs of corneal-arcus formation and their related diagnostics potentials have found that there is a strong correlation of the arcus formation with the risk of coronary artery diseases and lipid stratification. Clinically the stages of the arcus formation are normally observed as separate grey-whitish arcs, that are formed at the inferior and then at the superior poles of the cornea. These arcs will by time being elongated to form a ring approximately 1 mm in width. In this paper, efforts to develop quantification system that is capable to recognize the stages of the arcus formation will be reported. The quantification was based on eye-images taken using prior developed low-cost digital image acquisition system, which self constructed from a plastic safety welding-goggle that was modified by placing two Logitec C525 webcam and LEDs lighting system. Pattern images of arcs with variation of arc's positions, lengths and thickness were used for pre-calibration purposes. Then these similar arcs are drawn on the of periphery of cornea images to simulate dummy corneal arcus, which mimick the stages of corneal arcus development. Using 672 data images, results of recognition show a good recognition rate, i.e. 93.6 % for determining arc's length (with maximum %RSD of 5.67 %) and 84.83 % for determining arc's thickness (with maximum %RSD of 5.67 %). Worser precision data were observed to happen for the small arc's length as well as small arc's thickness. Current efforts are devoted to translate the system for clinical trials.

  11. Evaluation of corneal changes after myopic LASIK using the Pentacam®

    Directory of Open Access Journals (Sweden)

    Khairat YM

    2013-09-01

    Full Text Available Yehia M Khairat, Yasser H Mohamed, Ismail ANO Moftah, Narden N Fouad Department of Ophthalmology, Faculty of Medicine, El-Minya University, Egypt Background: In this study, we used a Pentacam® device to evaluate the corneal changes that occur after laser-assisted in situ keratomileusis (LASIK. Methods: Our study included 60 eyes of 32 patients. All patients were treated for myopia and myopic astigmatism using LASIK. The eyes were examined preoperatively and 3 months postoperatively using a Pentacam to assess corneal changes with regard to curvature, elevation, and asphericity of the cornea. Results: A statistically significant decrease in mean keratometric power of the anterior corneal surface (P = 0.001 compared with its pre-LASIK value was detected after 3 months, but there was no significant change in keratometric power of the posterior surface (P = 0.836. Asphericity (Q-value of the anterior and posterior surfaces increased significantly after LASIK (P = 0.001. A significant forward bulge of the anterior corneal surface 4 mm and 7 mm from the central zone was detected 3 months post-LASIK (P = 0.001 for both, but there was no significant increase in posterior elevation at 4 mm and 7 mm from the center (P = 0.637 and P = 0.26, respectively. No cases of post-LASIK ectasia were detected. Correlation between different parameters of the corneal surface revealed an indirect relation between changes in pachymetry and anterior corneal elevation at 4 mm and 7 mm from the central zone (r = −0.27, P = 0.13, and r = −0.37, P = 0.04, respectively, and a direct proportion between changes in pachymetry and mean keratometric power of the anterior and posterior corneal surfaces (r = 0.7, P = 0.001 and r = 0.4, P = 0.028, respectively. Conclusion: LASIK causes significant changes at the anterior corneal surface but the effect is subtle and insignificant at the posterior surface. Keywords: LASIK, laser-assisted in situ keratomileusis, Pentacam®, corneal

  12. Efecto de la sedación con dexmedetomidina sobre la presión intraocular y el espesor central de la córnea en perros (Effects of the dexmedetomidine sedation on intraocular pressure and on the central cornea thickness in the dog

    Directory of Open Access Journals (Sweden)

    Cristóbal-Gómez, L.

    2009-05-01

    Full Text Available ResumenDeterminar el efecto de la sedación con dexmedetomidinasobre la presión intraocular (PIO y el espesor central de la córnea (ECC en perros Material y métodos: Estudio realizado en 10 perros a los que se midió la PIO y ECC basales y tras administración tópica de tropicamida 1%. Seguidamente sedamos con dexmedetomidina 5µg/kg IV y valoramos PIO y ECC a los 5,10, 15 y 20 minutos post-sedación. Los valores medios se compararon mediante la prueba t de Student para muestras pareadas. Resultados: Los valores medios basales de PIO fueron media ± D.E. 10,95 ± 1,70 mmHg; y 571 ± 21,42 µm para el ECC. No existe asociación significativa entre PIO y ECC (r= -0,2399. La midriasis no varió significativamente los valores de PIO (P= 0,3665 pero sí el ECC (P=5,6109x10-6. La sedación con dexmedetomidina no varía significativamente los valores de PIO ni ECC (P>0,05. Conclusiones midriasis provocada por tropicamida 1% disminuyesignificativamente el ECC pero no la PIO. La sedación condexmedetomidina 5 mg/kg IV no varía significativamente los valores basales de PIO ni del ECC.SummaryObjective: to determine the effects of the dexmedetomidine sedation onintraocular pressure (IOP and on the central corneal thickness (CCT.Material and methods: this study has been performed over 10 dogstreated in the Veterinary Clinical Hospital of Córdoba University. The IOP and the CCT were measured before and after administration of one drop of 1% tropicamide. Thereafter, they were sedated with dexmedetomidine 5 µg/kg IV, and IOP and CCT were evaluated at 5, 10, 15 and 20 minutes after sedation. A t-Student test was performed with paired samples of mean values in order to compare both groups.Results: Basal values of IOP were 10.95 ± 1.70 mmHg, whereas CCTmean values were 571 ± 21.42µm. There were no statistically significant association between IOP and CCT (Pearson correlation r= -0.2399.Mydriasis did not significantly change the values of IOP (P= 0

  13. [Corneal tatoo--art or science?].

    Science.gov (United States)

    Craiu, Andreea-Madalina

    2009-01-01

    The permanent colouring of disfigured corneal scars is known for almost 200 years. Because of improvement in surgical reconstructive techniques, corneal tattoing is used today only with a restricted group on carefully chosen patients, and merely for esthetique reasons. PMID:19697848

  14. Metallic corneal foreign bodies: an occupational health hazard

    Directory of Open Access Journals (Sweden)

    Zeynep Gursel Ozkurt

    2014-04-01

    Full Text Available Purpose: To analyze the risk factors, outcomes, demographic characteristics, and attitudes of workers with metallic corneal foreign body (FB injury. Methods: One hundred consecutive patients who presented with a metallic corneal FB to the eye clinic at Diyarbakir Training and Research Hospital were evaluated. The patients completed a questionnaire and were examined to determine features of the injury. Results: All patients were male. The mean age was 32.46 ± 1.03 years. Fiftyfive percent of the patients were unregistered workers, 59% were working in the metal industry sector, and 65% injuries resulted from metal cutting. Protective goggles were available in the workplace of 64% patients. However, 57% patients were not wearing goggles when the accident occurred, and 43% were injured despite goggle use. Most patients (52% attempted to remove FBs by themselves. FBs were located in the central zone of the cornea in 16% patients. Rust marks remained after FB removal in 26% patients. Corneal scars from previous FB injuries were present in 58% patients. Only 8% workplaces provided compensation for physician visits for occupation related illnesses. Conclusions: Workplaces with a high risk for eye injuries should increase their protective measures, and educational programs should be implemented for both workers and occupational physicians. The government should enforce laws regarding unregistered workers in a better manner.

  15. Effects of Topically Applied Vitamin D during Corneal Wound Healing

    Science.gov (United States)

    Reins, Rose Y.; Hanlon, Samuel D.; Magadi, Sri; McDermott, Alison M.

    2016-01-01

    Vitamin D is an important regulator of immune function and largely acts to dampen chronic inflammatory events in a variety of tissues. There is also accumulating evidence that vitamin D acts to enhance initial inflammation, beneficial during both infection and wound healing, and then promotes resolution and prevention of chronic, damaging inflammation. The current study examines the effect of topical vitamin D in a mouse of model of corneal epithelial wound healing, where acute inflammation is necessary for efficient wound closure. At 12 and 18 hours post-wounding, vitamin D treatment significantly delayed wound closure by ~17% and increased infiltration of neutrophils into the central cornea. Basal epithelial cell division, corneal nerve density, and levels of VEGF, TGFβ, IL-1β, and TNFα were unchanged. However, vitamin D increased the production of the anti-microbial peptide CRAMP 12 hours after wounding. These data suggest a possible role for vitamin D in modulating corneal wound healing and have important implications for therapeutic use of vitamin D at the ocular surface. PMID:27035345

  16. Corneal abrasions associated with pepper spray exposure.

    Science.gov (United States)

    Brown, L; Takeuchi, D; Challoner, K

    2000-05-01

    Pepper spray containing oleoresin capsicum is used by law enforcement and the public as a form of nonlethal deterrent. Stimulated by the identification of a case of a corneal abrasion associated with pepper spray exposure, a descriptive retrospective review of a physician-maintained log of patients presenting to a jail ward emergency area over a 3-year period was performed. The objective was to give some quantification to the frequency with which an emergency physician could expect to see corneal abrasions associated with pepper spray exposure. Of 100 cases of pepper spray exposure identified, seven patients had sustained corneal abrasions. We conclude that corneal abrasions are not rare events when patients are exposed to pepper spray and that fluorescein staining and slit lamp or Wood's lamp examination should be performed on all exposed patients in whom corneal abrasions cannot be excluded on clinical grounds. PMID:10830682

  17. Management of pediatric corneal limbal dermoids

    Directory of Open Access Journals (Sweden)

    Pirouzian A

    2013-03-01

    Full Text Available Amir Pirouzian1,21Tayani Institute, Division of Ophthalmology and Cornea, Mission Viejo in affiliation with Children’s Hospital of Orange County at Mission Hospital, CA, USA; 2Rady’s Children’s Hospital of San Diego, San Diego, CA, USAAbstract: This paper reviews the data in the published literature (PubMed from 1937 to 2011 concerning the medical and surgical management of pediatric limbal dermoids. Current standard medical treatment for grade I pediatric limbal dermoids (ie, with superficial corneal involvment is initially conservative. In stages II (ie, affecting the full thickness of the cornea with/without endothelial involvement and III (ie, involvement of entire cornea and anterior chamber, a combination of excision, lamellar keratoplasty, and amniotic membrane and limbal stem cell tranplantation are advocated. Combinations of these approaches seem to yield better and more stable long-term ocular surface cosmesis and fewer complications in comparison with traditional methods of excision and lamellar keratoplasty. Management of amblyopia (i.e. occlusion treatment, chemical penalization with/without spectacle wear, etc must continue after surgical excision to yield optimal results when or if the surgery is done at a younger age.Keywords: limbal dermoid, amniotic membrane, surgical management, tissue adhesive

  18. Localisation of corneal foreign bodies.

    OpenAIRE

    Kay-Wilson, L. G.

    1992-01-01

    Of 50 patients attending the eye casualty department with a corneal foreign body (FB), 41 were able to say where they felt the FB and 78% of these were localised correctly for side or level of cornea. Patient handedness did not influence FB location. Indicating the upper lid was a particularly poor guide to localisation, whereas FB sensations within the palpebral fissure, in the lower lid or medially or laterally were good guides to actual FB location. A simple method of recording FB location...

  19. Comparison of central corneal thickness measurement with Pentacam, Sirius and an ultrasonic pachymeter%Pentacam和Sirius地形图系统与超声测厚仪角膜厚度的对比研究

    Institute of Scientific and Technical Information of China (English)

    郭慧; 顾宝文; 杨旭; 张醇; 肖海华

    2012-01-01

    目的:探讨Sirius与Pentacam及超声测厚仪测量中央角膜厚度的一致性.方法:对51例102眼正常人采用Pentacam和Sirius及超声角膜测厚仪三种仪器测量角膜厚度,记录并比较三种方法测量所得中央角膜厚度结果,同时运用Bland-Altman法绘制图表分析两两间一致性.结果:A超中央角膜厚度平均值低于 Pentacam的平均值,Sirius中央角膜厚度的平均值最接近A超平均值.Sirius与Pentacam一致性的比较:其Bland-Altman图中3.92%的点在95%一致性界限以外.在一致性界限以内,Sirius与Pentacam中央角膜厚度差值的绝对值最大为19.5μm.Sirius与A超一致性的比较:其Bland-Altman图中2.94%的点在95%一致性界限以外.在一致性界限以内,Sirius与A超中央角膜厚度差值的绝对值最大为18.667μm.Pentacam与A超一致性的比较:其Bland-Altman图中5 82%点在95%一致性界限以外.在一致性界限以内,Pentacam与A超中央角膜厚度差值的绝对值最大为25 33μm.结论:Sirius系统与Pentacam系统具有良好的一致性,且Sirius系统比Pentacam系统更接近A超角膜测厚的结果.

  20. Corneal Sensitivity and Dry Eye Symptoms in Patients with Keratoconus

    Science.gov (United States)

    Dienes, Lóránt; Kiss, Huba J.; Perényi, Kristóf; Nagy, Zoltán Z.; Acosta, M. Carmen; Gallar, Juana; Kovács, Illés

    2015-01-01

    Purpose To investigate corneal sensitivity to selective mechanical, chemical, and thermal stimulation and to evaluate their relation to dry eye symptoms in patients with keratoconus. Methods Corneal sensitivity to mechanical, chemical, and thermal thresholds were determined using a gas esthesiometer in 19 patients with keratoconus (KC group) and in 20 age-matched healthy subjects (control group). Tear film dynamics was assessed by Schirmer I test and by the non-invasive tear film breakup time (NI-BUT). All eyes were examined with a rotating Scheimpflug camera to assess keratoconus severity. Results KC patients had significatly decreased tear secretion and significantly higher ocular surface disease index (OSDI) scores compared to controls (5.3±2.2 vs. 13.2±2.0 mm and 26.8±15.8 vs. 8.1±2.3; p0.05). The mean threshold for selective mechanical (KC: 139.2±25.8 vs. control: 109.1±24.0 ml/min), chemical (KC: 39.4±3.9 vs. control: 35.2±1.9%CO2), heat (KC: 0.91±0.32 vs. control: 0.54±0.26 Δ°C) and cold (KC: 1.28±0.27 vs. control: 0.98±0.25 Δ°C) stimulation in the KC patients were significantly higher than in the control subjects (p0.05), whereas in the control subjects both mechanical (r = 0.52, p = 0.02), chemical (r = 0.47, p = 0.04), heat (r = 0.26, p = 0.04) and cold threshold (r = 0.40, p = 0.03) increased with age. In the KC group, neither corneal thickness nor tear flow, NI-BUT or OSDI correlated significantly with mechanical, chemical, heat or cold thresholds (p>0.05 for all variables). Conclusions Corneal sensitivity to different types of stimuli is decreased in patients with keratoconus independently of age and disease severity. The reduction of the sensory input from corneal nerves may contribute to the onset of unpleasant sensations in these patients and might lead to the impaired tear film dynamics. PMID:26495846

  1. Evaluation of the cytotoxic effects of ophthalmic solutions containing benzalkonium chloride on corneal epithelium using an organotypic 3-D model

    Directory of Open Access Journals (Sweden)

    Jessen Bart A

    2009-07-01

    Full Text Available Abstract Background Benzalkonium chloride (BAC is a common preservative used in ophthalmic solutions. The aim of this study was to compare the cytotoxic effects of BAC-containing ophthalmic solutions with a BAC-free ophthalmic solution using an organotypic 3-dimensional (3-D corneal epithelial model and to determine the effects of latanoprost ophthalmic solution and its BAC-containing vehicle on corneal thickness in a monkey model. Methods The cytotoxicity of commercially available BAC-containing ophthalmic formulations of latanoprost (0.02% BAC and olopatadine (0.01% BAC was compared to that of BAC-free travoprost and saline in a corneal organotypic 3-D model using incubation times of 10 and 25 minutes. To compare the extent of differentiation of 3-D corneal cultures to monolayer transformed human corneal epithelial (HCE-T cell cultures, expression levels (mRNA and protein of the corneal markers epidermal growth factor receptor, transglutaminase 1 and involucrin were quantified. Finally, latanoprost ophthalmic solution or its vehicle was administered at suprapharmacologic doses (two 30 μL drops twice daily in 1 eye for 1 year in monkey eyes, and corneal pachymetry was performed at baseline and at weeks 4, 13, 26 and 52. Results In the 3-D corneal epithelial culture assays, there were no significant differences in cytotoxicity between the BAC-containing latanoprost and olopatadine ophthalmic solutions and BAC-free travoprost ophthalmic solution at either the 10- or 25-minute time points. The 3-D cultures expressed higher levels of corneal epithelial markers than the HCE-T monolayers, indicating a greater degree of differentiation. There were no significant differences between the corneal thickness of monkey eyes treated with latanoprost ophthalmic solution or its vehicle (both containing 0.02% BAC and untreated eyes. Conclusion The lack of cytotoxicity demonstrated in 3-D corneal cultures and in monkey studies suggests that the levels of BAC

  2. Distribution of Posterior Corneal Astigmatism According to Axis Orientation of Anterior Corneal Astigmatism

    OpenAIRE

    Miyake,Toshiyuki; Shimizu, Kimiya; Kamiya, Kazutaka

    2015-01-01

    Purpose To investigate the distribution of posterior corneal astigmatism in eyes with with-the-rule (WTR) and against-the-rule (ATR) anterior corneal astigmatism. Methods We retrospectively examined six hundred eight eyes of 608 healthy subjects (275 men and 333 women; mean age ± standard deviation, 55.3 ± 20.2 years). The magnitude and axis orientation of anterior and posterior corneal astigmatism were determined with a rotating Scheimpflug system (Pentacam HR, Oculus) when we divided the su...

  3. Analysis of Postoperative Corneal Astigmatism after Phacoemulsification Through a Clear Corneal Incision

    OpenAIRE

    Sušić, Nikola; Brajković, Jasenka; Kalauz-Surać, Ivana

    2007-01-01

    The aim of the study was to analyze postoperative corneal astigmatism after phacoemulsification with intraocular lens implantation through a clear corneal incision. This prospective study included 22 eyes (10 right and 12 left eyes) having had phacoemulsification with implantation of a foldable intraocular lens through a clear corneal incision. A superotemporal incision was used in all right eyes, and superonasal incision in all left eyes. Astigmatism was measured by autorefractometer-keratom...

  4. Technology needs for corneal transplant surgery

    Science.gov (United States)

    Vaddavalli, Pravin K.; Yoo, Sonia H.

    2011-03-01

    Corneal transplant surgery has undergone numerous modifications over the years with improvements in technique, instrumentation and eye banking. The main goals of corneal transplantation are achieving excellent optical clarity with long-term graft survival. Penetrating, anterior and posterior lamellar surgery along with femtosecond laser technology have partially met these goals, but outcomes are often unpredictable and surgeon dependent. Technology to predictably separate stroma from Descemet's membrane, techniques to minimize endothelial cell loss, improvements in imaging technology and emerging techniques like laser welding that might replace suturing, eventually making corneal transplantation a refractively predictable procedure are on the wish list of the cornea surgeon.

  5. Self-organized centripetal movement of corneal epithelium in the absence of external cues

    Science.gov (United States)

    Lobo, Erwin P.; Delic, Naomi C.; Richardson, Alex; Raviraj, Vanisri; Halliday, Gary M.; di Girolamo, Nick; Myerscough, Mary R.; Lyons, J. Guy

    2016-08-01

    Maintaining the structure of the cornea is essential for high-quality vision. In adult mammals, corneal epithelial cells emanate from stem cells in the limbus, driven by an unknown mechanism towards the centre of the cornea as cohesive clonal groups. Here we use complementary mathematical and biological models to show that corneal epithelial cells can self-organize into a cohesive, centripetal growth pattern in the absence of external physiological cues. Three conditions are required: a circumferential location of stem cells, a limited number of cell divisions and mobility in response to population pressure. We have used these complementary models to provide explanations for the increased rate of centripetal migration caused by wounding and the potential for stem cell leakage to account for stable transplants derived from central corneal tissue, despite the predominantly limbal location of stem cells.

  6. A Case of Medication-Resistant Acanthamoeba Keratitis Treated by Corneal Crosslinking in Turkey

    Directory of Open Access Journals (Sweden)

    Goktug Demirci

    2013-01-01

    Full Text Available Purpose. To report a case of medication-resistant acanthamoeba keratitis (AK treated successfully by corneal crosslinking (CXL. Methods. A 26-year-old male with medication-resistant AK underwent a standard CXL procedure with local anesthesia, followed by central corneal epithelial debridement, application of riboflavin 0.1%, and UV-A irradiation. Results. The patient experienced a dramatic symptomatic improvement within 24 hours. At two months, keratitis was healed with a semitransparent paracentral scar that did not affect visual acuity. Conclusions. Our experience, considered in the context of recent studies, suggests that CXL may be an option for selected patients with medication-resistant AK and corneal melting. CXL allows patients to avoid emergency keratoplasty and experience rapid symptomatic relief.

  7. Confocal comparison of corneal reinnervation after small incision lenticule extraction (SMILE and femtosecond laser in situ keratomileusis (FS-LASIK.

    Directory of Open Access Journals (Sweden)

    Meiyan Li

    Full Text Available PURPOSE: To evaluate corneal reinnervation, and the corresponding corneal sensitivity and keratocyte density after small incision lenticule extraction (SMILE and femtosecond laser in situ keratomileusis (FS-LASIK. METHODS: In this prospective, non-randomized observational study, 18 patients (32 eyes received SMILE surgery, and 22 patients (42 eyes received FS-LASIK surgery to correct myopia. The corneal subbasal nerve density and microscopic morphological changes in corneal architecture were evaluated by confocal microscopy prior to surgery and at 1 week, 1 month, 3 months, and 6 months after surgery. A correlation analysis was performed between subbasal corneal nerve density and the corresponding keratocyte density and corneal sensitivity. RESULTS: The decrease in subbasal nerve density was less severe in SMILE-treated eyes than in FS-LASIK-treated eyes at 1 week (P = 0.0147, 1 month (P = 0.0243, and 3 months (P = 0.0498, but no difference was detected at the 6-month visit (P = 0.5277. The subbasal nerve density correlated positively with central corneal sensitivity in both groups (r = 0.416, P<0.0001, and r = 0.2567, P = 0.0038 for SMILE group and FS-LASIK group, respectively. The SMILE-treated eyes have a lower risk of developing peripheral empty space with epithelial cells filling in (P = 0.0005. CONCLUSIONS: The decrease in subbasal nerve fiber density was less severe in the SMILE group than the FS-LASIK group in the first 3 months following the surgeries. The subbasal nerve density was correlated with central corneal sensitivity.

  8. EDC/NHS cross-linked collagen foams as scaffolds for artificial corneal stroma.

    Science.gov (United States)

    Vrana, N E; Builles, N; Kocak, H; Gulay, P; Justin, V; Malbouyres, M; Ruggiero, F; Damour, O; Hasirci, V

    2007-01-01

    In this study, a highly porous collagen-based biodegradable scaffold was developed as an alternative to synthetic, non-degradable corneal implants. The developed method involved lyophilization and subsequent stabilization through N-ethyl-N'-[3-dimethylaminopropyl] carbodiimide/N-hydroxy succinimide (EDC/NHS) cross-linking to yield longer lasting, porous scaffolds with a thickness similar to that of native cornea (500 microm). For collagen-based scaffolds, cross-linking is essential; however, it has direct effects on physical characteristics crucial for optimum cell behavior. Hence, the effect of cross-linking was studied by examining the influence of cross-linking on pore size distribution, bulk porosity and average pore size. After seeding the foam with human corneal keratocytes, cell proliferation, cell penetration into the scaffold and ECM production within the scaffold were studied. After a month of culture microscopical and immunohistochemical examinations showed that the foam structure did not undergo any significant loss of integrity, and the human corneal keratocytes populated the scaffold with cells migrating both longitudinally and laterally, and secreted some of the main constituents of the corneal ECM, namely collagen types I, V and VI. The foams had a layer of lower porosity (skin layer) both at the top and the bottom. Foams had an optimal porosity (93.6%), average pore size (67.7 microm), and chemistry for cell attachment and proliferation. They also had a sufficiently rapid degradation rate (73.6+/-1.1% in 4 weeks) and could be produced at a thickness close to that of the natural corneal stroma. Cells were seeded at the top surface of the foams and their numbers there was higher than the rest, basically due to the presence of the skin layer. This is considered to be an advantage when epithelial cells need to be seeded for the construction of hemi or full thickness cornea. PMID:17988518

  9. Photodynamic therapy with verteporfin for corneal neovascularization

    Directory of Open Access Journals (Sweden)

    Abdullah A Al-Torbak

    2012-01-01

    Results: At the last follow-up visit, 22 (66.7% eyes showed a decrease in corneal neovascularization and evidence of vascular thrombosis. Complete vascular occlusion was achieved in 14 (42.4% eyes, partial occlusion was achieved in 8 (24.2% eyes, and the vessels were patent in 11 (33.3% eyes. The corneal neovascularization score and depth of the vessels were found to be significant risk factors for failure (P = 0.0001 and 0.046, respectively. However, the diagnoses or causes of corneal neovascularisation were not statistically significant. No significant systemic or ocular complications associated with photodynamic therapy were observed. Conclusion: Photodynamic therapy with verteporfin was effective for the treatment of corneal neovascularization in the majority of the cases in this study.

  10. Clear corneal incision in cataract surgery

    Directory of Open Access Journals (Sweden)

    Ammar M Al Mahmood

    2014-01-01

    Full Text Available Since the introduction of sutureless clear corneal cataract incisions, the procedure has gained increasing popularity worldwide because it offers several advantages over the traditional sutured scleral tunnels and limbal incisions. Some of these benefits include lack of conjunctival trauma, less discomfort and bleeding, absence of suture-induced astigmatism, and faster visual rehabilitation. However, an increasing incidence of postoperative endophthalmitis after clear corneal cataract surgery has been reported. Different authors have shown a significant increase up to 15-fold in the incidence of endophthalmitis following clear corneal incision compared to scleral tunnels. The aim of this report is to review the advantages and disadvantages of clear corneal incisions in cataract surgery, emphasizing on wound construction recommendations based on published literature.

  11. Corneal wound healing after laser vision correction.

    Science.gov (United States)

    Spadea, Leopoldo; Giammaria, Daniele; Trabucco, Paolo

    2016-01-01

    Any trauma can trigger a cascade of responses in tissues, with the purpose of safeguarding the integrity of the organ affected by the trauma and of preventing possible damage to nearby organs. Subsequently, the body tries to restore the function of the organ affected. The introduction of the excimer laser for keratorefractive surgery has changed the treatment landscape for correcting refractive errors, such as myopia, hyperopia, and astigmatism. In recent years, with the increased understanding of the basic science of refractive errors, higher-order aberrations, biomechanics, and the biology of corneal wound healing, a reduction in the surgical complications of keratorefractive surgery has been achieved. The understanding of the cascade of events involved in the corneal wound healing process and the examination of how corneal wound healing influences corneal biomechanics and optics are crucial to improving the efficacy and safety of laser vision correction. PMID:26405102

  12. Keratocytes are induced to produce collagen type II: A new strategy for in vivo corneal matrix regeneration.

    Science.gov (United States)

    Greene, Carol Ann; Green, Colin R; Dickinson, Michelle E; Johnson, Virginia; Sherwin, Trevor

    2016-09-10

    The stroma, the middle layer of the cornea, is a connective tissue making up most of the corneal thickness. The stromal extracellular matrix (ECM) consists of highly organised lamellae which are made up of tightly packed fibrils primarily composed of collagens type I and V. This layer is interspersed with keratocytes, mesenchymal cells of neural crest origin. We have previously shown that adult corneal keratocytes exhibit phenotypic plasticity and can be induced into a neuronal phenotype. In the current study we evaluated the potential of keratocytes to produce collagen type II via phenotypic reprogramming with exogenous chondrogenic factors. The cornea presents a challenge to tissue engineers owing to its high level of organisation and the phenotypic instability of keratocytes. Traditional approaches based on a scar model do not support the engineering of functional stromal tissue. Type II collagen is not found in the adult cornea but is reported to be expressed during corneal development, raising the possibility of using such an approach to regenerate the corneal ECM. Keratocytes in culture and within intact normal and diseased tissue were induced to produce collagen type II upon treatment with transforming growth factor Beta3 (TGFβ3) and dexamethasone. In vivo treatment of rat corneas also resulted in collagen type II deposition and a threefold increase in corneal hardness and elasticity. Furthermore, the treatment of corneas and subsequent deposition of collagen type II did not cause opacity, fibrosis or scarring. The induction of keratocytes with specific exogenous factors and resulting deposition of type II collagen in the stroma can potentially be controlled by withdrawal of the factors. This might be a promising new approach for in vivo corneal regeneration strategies aimed at increasing corneal integrity in diseases associated with weakened ectatic corneal tissue such as keratoconus. PMID:27539660

  13. Corneal damage following focal laser intervention

    International Nuclear Information System (INIS)

    Corneal endothelial damage caused by two levels of laser energy was studied in albino rats. Observations indicate that focal, non-invasive destruction of the endothelium can be consistently generated by laser treatment following anterior chamber localization of fluorescein. The dose related effects of this described protocol will make it possible to study different aspects of posterior corneal function without generating invasive, inflammatory side effects. (author)

  14. Phacoemulsification in Cases with Corneal Opacity

    OpenAIRE

    Elif Erdem; Kemal Yar; Hande Taylan Şekeroğlu; Meltem Yağmur

    2011-01-01

    Pur po se: To assess the results of phacoemulsification in patients with corneal opacity and cataract. Ma te ri al and Met hod: Fifteen eyes of 13 patients who were diagnosed as senile cataract and corneal opacity were included in the present study. All surgeries were performed under topical anesthesia. Trypan blue (0.1%) was used during the capsulorrhexis step of phacoemulsification. Following hydrodissection, phacoemulsification was performed using “quick chop” technique. Postopera...

  15. Temporal corneal phacoemulsification in filtered glaucoma patients.

    OpenAIRE

    Caprioli, J.; Park, H.J.; Kwon, Y. H.; Weitzman, M

    1997-01-01

    PURPOSE: To evaluate the effect of temporal clear corneal phacoemulsification on intraocular pressure (IOP) in eyes that had prior trabeculectomy. DESIGN: Retrospective case-control study. PATIENTS: Forty consecutive patients (cases; TRAB-PHACO group) who underwent temporal corneal phacoemulsification subsequent to trabeculectomy were identified. Forty patients (controls; TRAB group) who had trabeculectomy alone were matched to the cases for length of follow-up, age, IOP, number of anti-glauc...

  16. Detecting thermal phase transitions in corneal stroma by fluorescence micro-imaging analysis

    Science.gov (United States)

    Matteini, P.; Rossi, F.; Ratto, F.; Bruno, I.; Nesi, P.; Pini, R.

    2008-02-01

    Thermal modifications induced in corneal stroma were investigated by the use of fluorescence microscopy. Freshly extracted porcine corneas were immersed for 5 minutes in a water bath at temperatures in the 35-90°C range and stored in formalin. The samples were then sliced in 200-μm-thick transversal sections and analyzed under a stereomicroscope to assess corneal shrinkage. Fluorescence images of the thermally treated corneal samples were acquired using a slow-scan cooled CCD camera, after staining the slices with Indocyanine Green (ICG) fluorescent dye which allowed to detect fluorescence signal from the whole tissue. All measurements were performed using an inverted epifluorescence microscope equipped with a mercury lamp. The thermally-induced modifications to the corneal specimens were evaluated by studying the grey level distribution in the fluorescence images. For each acquired image, Discrete Fourier Transform (DFT) and entropy analyses were performed. The spatial distribution of DFT absolute value indicated the spatial orientation of the lamellar planes, while entropy was used to study the image texture, correlated to the stromal structural transitions. As a result, it was possible to indicate a temperature threshold value (62°C) for high thermal damage, resulting in a disorganization of the lamellar planes and in full agreement with the measured temperature for corneal shrinkage onset. Analysis of the image entropy evidenced five strong modifications in stromal architecture at temperatures of ~45°C, 53°C, 57°C, 66°C, 75°C. The proposed procedure proved to be an effective micro-imaging method capable of detecting subtle changes in corneal tissue subjected to thermal treatment.

  17. Phenotypic Spectrum of Granular Corneal Dystrophy Type II in Two Italian Families Presenting an Unusual Granular Corneal Dystrophy Type I Clinical Appearance

    Directory of Open Access Journals (Sweden)

    Cosimo Mazzotta

    2015-01-01

    Full Text Available Clinical, instrumental, and genetic findings are reported in Italian families with Type II Granular Corneal Dystrophies (GCD2 presenting an initial unusual presentation of a Granular Corneal Dystrophy Type I (GCD1 phenotypic spectrum in female descendants. Slit-lamp examinations showed the typical phenotypic features of GCD2 in both mothers and a phenotypic appearance of GCD1 in both daughters. Despite the different phenotypic onset, the genetic diagnostic testing revealed the presence of a mutation in the TGFB-I gene, typical of GCD2 in both cases, excluding GCD1. Patients who were clinically suspected of corneal dystrophy need a genetic confirmatory testing for certain diagnosis. Genetic test may help to find the specific mutation distinguishing between different phenotypic spectra with relative diagnostic and prognostic implications. The study demonstrates that the phenotypic spectrum of genetically confirmed granular corneal dystrophies in patients may change over time. Since the R124H mutation has also been described in clinically asymptomatic individuals prior to LASIK, who then develop dramatic deposition, suggesting that this particular mutation and phenotype may be sensitive to, precipitated, or modified by central cornea trauma, a careful familial anamnesis excluding cornel dystrophies and specific preoperative genetic test are recommended prior to LASIK.

  18. "All-laser" endothelial corneal transplant in human patients

    Science.gov (United States)

    Rossi, Francesca; Menabuoni, Luca; Malandrini, Alex; Canovetti, Annalisa; Lenzetti, Ivo; Pini, Roberto

    2012-03-01

    Femtosecond laser sculpturing of corneal tissue is commonly used for the preparation of endothelial flaps. Diode laser welding of ocular tissues is a procedure that enables minimally invasive suturing of tissues. The combination of these laser based techniques results in a new approach to minimally invasive ophthalmic surgery, such as in endothelial corneal transplant (or endothelial keratoplasty - EK). In this work we present the "all laser" EK performed in human subjects. 24 pseudophakic patients with bullous keratopathy underwent EK: the femtosecond laser was used to prepare the 100 ìm thick and 8.5 mm diameter donor Descemet endothelial flap. After staining the stromal layer of the donor flap with a liquid ICG solution, the donor flap was inserted in the recipient eye by the use of the Busin injector. Then, the endothelial layer was laser-welded to the recipient eye (10 laser spots around the periphery of the flap), in order to reduce the risk of postoperative dislocation of the transplanted flap. A transplanted flap engraftment was observed in all the treated eyes. The staining procedure used to perform laser welding also enabled to evidence the stromal side of the donor flap, so as the flap was always placed in the right side position. The endothelial cells counts in both the laserwelded flaps and in a control group were in good agreement. The proposed technique is easy to perform and enables the reduction of postoperative endothelial flap dislocations.

  19. Critical head, thickness of fine-grained deposit, and skeletal elastic storage arrays of the SUB package of the Central Valley Hydrologic Model

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset defines the SUB package arrays for the model grid, critical head, thickness of fine-grained deposits, and skeletal-elastic-storage used in the...

  20. Effect of detergents on corneal permeability

    International Nuclear Information System (INIS)

    Changes of corneal permeability for 22Na caused by benzalkonium chloride (BAC) and the Czechoslovak detergent Jar were tested in vitro as well as in vivo. Experiments in vitro were performed on corneas of bovine eyes incubated at 37 degC. During a 10 min span the corneal surface was wetted with nine drops of aqueous solutions of BAC (0.001%, 0.01%, 0.1%, 1% and 10.0%, resp.) and Jar (0.01%, 0.1%, 1.0%, 10.0% and 100.0%, i.e., commercialy available compound, resp.). Changes of corneal permeability caused by detergents were demonstrated by an increaseJ uptake of 22Na transferred from the paper strips stretched over the corneal surface. For the controls, saline was used instead of detergents. The corneal permeability for 22Na increased with increasing detergent concentration. Significant changes of corneal permeability were caused by Jar diluted to 0.01%. Experiments in vivo were carried out on rabbits. Both detergents were tested in above mentioned concetrations using always two drops during a 1 min exposure. The eyes were observed for 6 days. Heavy keratitis with corneal edema, purulent conjunctival discharge and blepharitis was caused by 10% BAC and to a lesser degree also by 1% BAC or undiluted Jar. On the seventh day the permeability of the rabbit corneas was tested applying the paper strips soaked with 22Na. After 30 min the rabbits were dissected and the radioactivity of the isolated tissues and aqueous has been evaluated. After the six days delay the functional changes of the epithelial barrier were still observable manifesting itself by changed permeability and ocular distribution of 22Na. (author)

  1. Genetics Home Reference: lattice corneal dystrophy type I

    Science.gov (United States)

    ... Diagnosis & Management These resources address the diagnosis or management of lattice corneal dystrophy type I: American Foundation for the Blind: Living with Vision Loss Genetic Testing Registry: Lattice corneal dystrophy Type ...

  2. Role of Decorin Core Protein in Collagen Organisation in Congenital Stromal Corneal Dystrophy (CSCD)

    Science.gov (United States)

    Kamma-Lorger, Christina S.; Pinali, Christian; Martínez, Juan Carlos; Harris, Jon; Young, Robert D.; Bredrup, Cecilie; Crosas, Eva; Malfois, Marc; Rødahl, Eyvind

    2016-01-01

    The role of Decorin in organising the extracellular matrix was examined in normal human corneas and in corneas from patients with Congenital Stromal Corneal Dystrophy (CSCD). In CSCD, corneal clouding occurs due to a truncating mutation (c.967delT) in the decorin (DCN) gene. Normal human Decorin protein and the truncated one were reconstructed in silico using homology modelling techniques to explore structural changes in the diseased protein. Corneal CSCD specimens were also examined using 3-D electron tomography and Small Angle X-ray diffraction (SAXS), to image the collagen-proteoglycan arrangement and to quantify fibrillar diameters, respectively. Homology modelling showed that truncated Decorin had a different spatial geometry to the normal one, with the truncation removing a major part of the site that interacts with collagen, compromising its ability to bind effectively. Electron tomography showed regions of abnormal stroma, where collagen fibrils came together to form thicker fibrillar structures, showing that Decorin plays a key role in the maintenance of the order in the normal corneal extracellular matrix. Average diameter of individual fibrils throughout the thickness of the cornea however remained normal. PMID:26828927

  3. Corneal Stromal Bioequivalents Secreted on Patterned Silk Substrates

    OpenAIRE

    Wu, Jian; Rnjak-Kovacina, Jelena; Du, Yiqin; Funderburgh, Martha L.; Kaplan, David L.; Funderburgh, James L.

    2014-01-01

    Emulating corneal stromal tissue is believed to be the most challenging step in bioengineering an artificial human cornea because of the difficulty in reproducing its highly ordered microstructure, the key to the robust biomechanical properties and optical transparency of this tissue. We conducted a comparative study to assess the feasibility of human corneal stromal stem cells (hCSSCs) and human corneal fibroblasts (hCFs) in the generation of human corneal stromal tissue on groove-patterned ...

  4. Evaluation of corneal higher order aberrations in normal topographic patterns

    OpenAIRE

    Mirzajani, Ali; Aghataheri, Sattar; Ghoreishi, Mohammad; Jafarzadepour, Ebrahim; Mohammadinia, Mohadese

    2016-01-01

    Purpose This study reports the characteristics of corneal higher order aberrations (HOAs) in eyes with normal topographic pattern using the Pentacam scheimpflug system. Methods In this prospective, observational, comparative study, 165 eyes of 97 patients separated into five groups based on corneal topographic patterns were enrolled. All eyes received a comprehensive ophthalmologic examination including corneal tomographic analysis with the Pentacam system. Keratometry, corneal cylinder, and ...

  5. Bilateral coexistence of keratoconus and macular corneal dystrophy

    Directory of Open Access Journals (Sweden)

    Ghazi Al-Hamdan

    2009-01-01

    The authors hereby report a 21-year-old female who presented with the typical signs and topographic evidence of keratoconus in association with macular corneal dystrophy. Histopathologic evaluation from the excised corneal button after corneal transplant confirmed the diagnosis. To our knowledge, there is only one previous report in the literature linking the association of keratoconus and macular corneal dystrophy in the same eye bilaterally.

  6. Acute Corneal Hydrops 3 Years after Intra-corneal Ring Segments and Corneal Collagen Cross-linking

    Science.gov (United States)

    Antonios, Rafic; Dirani, Ali; Fadlallah, Ali; Chelala, Elias; Hamadeh, Adib; Jarade, Elias

    2016-01-01

    This case report describes a 15-year-old male with allergic conjunctivitis and keratoconus, who underwent uneventful intra-corneal ring segment (ICRS) implantation and corneal collagen cross-linking (CXL) in the right eye. During the follow-up periods, the patient was noted to have several episodes of allergic conjunctivitis that were treated accordingly. At the 2 years postoperatively, he presented with another episode of allergic conjunctivitis and progression of keratoconus was suspected on topography. However, the patient was lost to follow-up, until he presented with acute hydrops at 3 years postoperatively. There are no reported cases of acute corneal hydrops in cross-linked corneas. We suspect the young age, allergic conjunctivitis and eye rubbing may be a risk factors associated with possible progression of keratoconus after CXL. Prolonged follow-up and aggressive control of the allergy might be necessary in similar cases. PMID:26957859

  7. Efficacy of Tectonic Corneal Patch Graft for Progressive Peripheral Corneal Thinning

    Directory of Open Access Journals (Sweden)

    Cafer Tanrıverdio

    2014-12-01

    Full Text Available Objectives: To report the results of tectonic corneal patch graft (TCPG in patients with progressive peripheral corneal thinning (PCT. Materials and Methods: In this study, we included 8 patients who underwent TCPG for PCT or perforated corneal ulceration at Ankara Training and Research Hospital. Results: We performed TCPG in 7 patients for PCT and in 1 patient for perforated corneal ulceration. Mean age was 57.2±16.7 (38- 82 years. Postoperative follow-up time ranged from 6 to 24 months (mean 13.9±6.7. Possible etiologies leading to progressive PCT were trachoma, infectious corneal ulcer, and rheumatoid arthritis-severe dry eye in 2 patients each. Other 2 patients had a progressive PCT following ocular surgery. One of the patients with infectious corneal ulcer also had a trauma caused by a scissor. Amnion membrane transplantation was performed in 3 patients prior to TCPG. While the anatomic success was achieved in all 8 patients, best-corrected visual acuity (BCVA was 0.1 or better in 4 patients (50%. Postoperative BCVA was better than preoperative BCVA in 6 patients (75%. Local peripheral anterior synechiae developed in two eyes. Conclusion: TCPG is a useful therapeutic option in selected cases of corneal thinning and perforations because it effectively restores the integrity of the globe and allows acceptable visual results. (Turk J Ophthalmol 2014; 44: 440-4

  8. Astigmatism in relation to length and site of corneal lacerations

    Directory of Open Access Journals (Sweden)

    Srihari Atti

    2016-01-01

    Conclusions: The corneal astigmatism depends upon the length and site of corneal laceration. Severity of astigmatism was directly proportion to the length of corneal laceration. The wound was nearer to the centre of the cornea, the greater was the astigmatism. [Int J Res Med Sci 2016; 4(1.000: 165-168

  9. A comparison of glycosaminoglycan distributions, keratan sulphate sulphation patterns and collagen fibril architecture from central to peripheral regions of the bovine cornea.

    Science.gov (United States)

    Ho, Leona T Y; Harris, Anthony M; Tanioka, Hidetoshi; Yagi, Naoto; Kinoshita, Shigeru; Caterson, Bruce; Quantock, Andrew J; Young, Robert D; Meek, Keith M

    2014-09-01

    This study investigated changes in collagen fibril architecture and the sulphation status of keratan sulphate (KS) glycosaminoglycan (GAG) epitopes from central to peripheral corneal regions. Freshly excised adult bovine corneal tissue was examined as a function of radial position from the centre of the cornea outwards. Corneal thickness, tissue hydration, hydroxyproline content, and the total amount of sulphated GAG were all measured. High and low-sulphated epitopes of keratan sulphate were studied by immunohistochemistry and quantified by ELISA. Chondroitin sulphate (CS) and dermatan sulphate (DS) distributions were observed by immunohistochemistry following specific enzyme digestions. Electron microscopy and X-ray fibre diffraction were used to ascertain collagen fibril architecture. The bovine cornea was 1021±5.42 μm thick at its outer periphery, defined as 9-12 mm from the corneal centre, compared to 844±8.10 μm at the centre. The outer periphery of the cornea was marginally, but not significantly, more hydrated than the centre (H=4.3 vs. H=3.7), and was more abundant in hydroxyproline (0.12 vs. 0.06 mg/mg dry weight of cornea). DMMB assays indicated no change in the total amount of sulphated GAG across the cornea. Immunohistochemistry revealed the presence of both high- and low-sulphated epitopes of KS, as well as DS, throughout the cornea, and CS only in the peripheral cornea before the limbus. Quantification by ELISA, disclosed that although both high- and low-sulphated KS remained constant throughout stromal depth at different radial positions, high-sulphated epitopes remained constant from the corneal centre to outer-periphery, whereas low-sulphated epitopes increased significantly. Both small angle X-ray diffraction and TEM analysis revealed that collagen fibril diameter remained relatively constant until the outer periphery was reached, after which fibrils became more widely spaced (from small angle x-ray diffraction analysis) and of larger diameter

  10. Corneal endothelial changes in superficial epithelial keratopathy.

    Science.gov (United States)

    Brooks, A M; Grant, G; Gillies, W E

    1986-05-01

    A series of five cases is described in which superficial punctate keratopathy was associated with endothelial cell changes. The most striking change was the presence of dark areas or blebs, usually two to four cell diameters in extent. There was also distortion and crumpling of the corneal endothelium, mild pleomorphism and polymegathism of the endothelial cells, with a reduced cell count in some cases. These blebs have previously been reported in hard and soft contact lens wearers and are due to intercellular oedema with separation of endothelial cells from Descemet's membrane. Anoxia and interference with osmosis have been proposed as possible mechanisms for the production of these blebs, but our cases demonstrate that fine disruption of the corneal epithelium can affect the integrity of the corneal endothelium and may lead to significant damage over a long period of time. PMID:3801208

  11. The outer vactank, an object of 7.6m diameter and 13m length is built up of three cylindrical parts. The central part that is integral part of the central barrel and the the extension on either side each one 4.5m long. These extensions house the shoulders that will support and prestress the CMS Coil. To weld the extensions onto the central part a full penetration weld of 24m length and 45 mm thickness has to be done by hand from inside and outside the vacuum tank and its deformation is controled permanently.

    CERN Multimedia

    Hubert Gerwig

    2001-01-01

    The outer vacuum tank will hold the coil suspension system and transmits the weight of the inner detectors to the central barrel. Its thickness is staggered. In the central part its thickness is 60 mm and then goes down to 30 mm at the extremity.

  12. Corneal collagen crosslinking for keratoconus. A review

    Directory of Open Access Journals (Sweden)

    M. M. Bikbov

    2014-10-01

    Full Text Available Photochemical crosslinking is widely applied in ophthalmology. Its biochemical effect is due to the release of singlet oxygen that promotes anaerobic photochemical reaction. Keratoconus is one of the most common corneal ectasia affecting 1 in 250 to 250 000 persons. Currently, the rate of iatrogenic ectasia following eximer laser refractive surgery increases due to biomechanical weakening of the cornea. Morphologically and biochemically, ectasia is characterized by corneal layers thinning, contact between the stroma and epithelium resulting from Bowman’s membrane rupture, chromatin fragmentation in keratocyte nuclei, phagocytosis, abnormal staining and arrangement of collagen fibers, enzyme system disorders, and keratocyte apoptosis. In corneal ectasia, altered enzymatic processes result in the synthesis of abnormal collagen. Collagen packing is determined by the activity of various extracellular matrix enzymes which bind amines and aldehydes of collagen fiber amino acids. In the late stage, morphological changes of Descemet’s membrane (i.e., rupture and detachment develop. Abnormal hexagonal-shaped keratocytes and their apoptosis are the signs of endothelial dystrophy. The lack of analogs in domestic ophthalmology encouraged the scientists of Ufa Eye Research Institute to develop a device for corneal collagen crosslinking. The parameters of ultraviolet (i.e., wavelength, exposure time, power to achieve the desired effect were identified. The specifics of some photosensitizers in the course of the procedure were studied. UFalink, a device for UV irradiation of cornea, and photosensitizer Dextralink were developed and adopted. Due to the high risk of endothelial damage, this treatment is contraindicated in severe keratoconus (CCT less than 400 microns. Major effects of corneal collagen crosslinking are the following: Young’s modulus (modulus of elasticity increase by 328.9 % (on average, temperature tolerance increase by 5

  13. Evaluation of Fungal Keratitis using a Newly Developed Computer Program, Optscore, for Grading Digital Corneal Photographs

    Science.gov (United States)

    Toutain-Kidd, Christine M.; Porco, Travis C.; Kidd, Eric M.; Srinivasan, M; Prajna, Namperumalsamy V.; Acharya, Nisha; Lietman, Thomas; Zegans, Michael E.

    2016-01-01

    Purpose To validate computer software developed to assess digital corneal photographs of fungal keratitis in clinical research. Methods A cornea specialist and five medical students (after training) graded on two occasions 100 corneal photographs of patients with fungal keratitis using Optscore software. Variables assessed were lesion area, location, degree of opacity, percentage of the ulcer lying within a central 4mm circle of the cornea. Intraclass correlation coefficients (ICCs) were used to assess intragrader reliability, agreement of the students with the corneal specialist, and the reliability of the group mean of the student raters. The area determined using Optscore was compared to the area estimated from slit lamp and to visual acuity. Results As a group, medical students achieved an ICC greater than 0.9 for five out of the seven assessed variables. Similar levels of consistency were found after analyzing the graders’ individual results compared to the specialist. The area estimated using slit lamp examination was highly correlated with the mean area determined by Optscore, as was the logarithm of the minimum angle of resolution visual acuity at enrollment. Conclusions Non-expert graders using Optscore to assess digital photographs of fungal keratitis are self-consistent, agree with an expert grader both as a group and individually, and measurements of ulcer area obtained from Optscore are highly correlated with measurements of the same patients obtained on clinical examination. These observations support the validity of Optscore for assessing corneal pathology associated with fungal keratitis and make it a promising clinical research tool. PMID:24467559

  14. Evaluation of Epithelial Integrity with Various Transepithelial Corneal Cross-Linking Protocols for Treatment of Keratoconus

    Directory of Open Access Journals (Sweden)

    Suphi Taneri

    2014-01-01

    Full Text Available Purpose. Corneal collagen cross-linking (CXL has been demonstrated to stiffen cornea and halt progression of ectasia. The original protocol requires debridement of central corneal epithelium to facilitate diffusion of a riboflavin solution to stroma. Recently, transepithelial CXL has been proposed to reduce risk of complications associated with epithelial removal. Aim of the study is to evaluate the impact of various transepithelial riboflavin delivery protocols on corneal epithelium in regard to pain and epithelial integrity in the early postoperative period. Methods. One hundred and sixty six eyes of 104 subjects affected by progressive keratoconus underwent transepithelial CXL using 6 different riboflavin application protocols. Postoperatively, epithelial integrity was evaluated at slit lamp and patients were queried regarding their ocular pain level. Results. One eye had a corneal infection associated with an epithelial defect. No other adverse event including endothelial decompensation or endothelial damage was observed, except for epithelial damages. Incidence of epithelial defects varied from 0 to 63%. Incidence of reported pain varied from 0 to 83%. Conclusion. Different transepithelial cross-linking protocols have varying impacts on epithelial integrity. At present, it seems impossible to have sufficient riboflavin penetration without any epithelial disruption. A compromise between efficacy and epithelial integrity has to be found.

  15. Intrastromal injection of bevacizumab in patients with corneal neovascularization

    Directory of Open Access Journals (Sweden)

    Ana Carolina Cabreira Vieira

    2012-08-01

    Full Text Available Corneal neovascularization (NV not only reduces visual acuity, but it also causes loss of the cornea's immune privilege, strongly contributing to a worse prognosis in penetrating keratoplasty. Several mediators participate in corneal angiogenesis, and the role of vascular endothelial growth factor (VEGF has been extensively proven. Anti-VEGF agents have been shown to be effective in slowing the growth of corneal neovessels. Bevacizumab, an anti-VEGF agent, has been successfully used in the treatment of corneal neovascularization. In this paper, we report a series of patients who underwent intracorneal bevacizumab injections to treat corneal vascularization.

  16. Clinical Factors Associated with Lamina Cribrosa Thickness in Patients with Glaucoma, as Measured with Swept Source Optical Coherence Tomography

    Science.gov (United States)

    Omodaka, Kazuko; Takahashi, Seri; Matsumoto, Akiko; Maekawa, Shigeto; Kikawa, Tsutomu; Himori, Noriko; Takahashi, Hidetoshi; Maruyama, Kazuichi; Kunikata, Hiroshi; Akiba, Masahiro; Nakazawa, Toru

    2016-01-01

    Purpose To investigate the influence of various risk factors on thinning of the lamina cribrosa (LC), as measured with swept-source optical coherence tomography (SS-OCT; Topcon). Methods This retrospective study comprised 150 eyes of 150 patients: 22 normal subjects, 28 preperimetric glaucoma (PPG) patients, and 100 open-angle glaucoma patients. Average LC thickness was determined in a 3 x 3 mm cube scan of the optic disc, over which a 4 x 4 grid of 16 points was superimposed (interpoint distance: 175 μm), centered on the circular Bruch’s membrane opening. The borders of the LC were defined as the visible limits of the LC pores. The correlation of LC thickness with Humphrey field analyzer-measured mean deviation (MD; SITA standard 24–2), circumpapillary retinal nerve fiber layer thickness (cpRNFLT), the vertical cup-to-disc (C/D) ratio, and tissue mean blur rate (MBR) was determined with Spearman's rank correlation coefficient. The relationship of LC thickness with age, axial length, intraocular pressure (IOP), MD, the vertical C/D ratio, central corneal thickness (CCT), and tissue MBR was determined with multiple regression analysis. Average LC thickness and the correlation between LC thickness and MD were compared in patients with the glaucomatous enlargement (GE) optic disc type and those with non-GE disc types, as classified with Nicolela’s method. Results We found that average LC thickness in the 16 grid points was significantly associated with overall LC thickness (r = 0.77, P Glaucoma patients with the GE disc type, who predominantly have large cupping, had lower LC thickness even with similar glaucoma severity. PMID:27100404

  17. Ultraviolet Light Transmission through the Human Corneal Stroma Is Reduced in the Periphery

    OpenAIRE

    Doutch, James J.; Quantock, Andrew J.; Joyce, Nancy C.; Meek, Keith M.

    2012-01-01

    This article investigates in vitro light transmission through the human cornea in the ultraviolet (UV) portion of the electromagnetic spectrum as a function of position across the cornea from center to periphery. Spectrophotometry was used to measure UV transmission in the wavelength range 310–400 nm, from the central cornea to its periphery. UV transmission decreases away from the center, and this is attributed to scattering and absorbance. Corneal endothelial cells, which line the back of t...

  18. Limit of blank and limit of detection of Plasmodium falciparum thick blood smear microscopy in a routine setting in Central Africa

    OpenAIRE

    Joanny, Fanny; Löhr, Sascha JZ; Engleitner, Thomas; Lell, Bertrand; Mordmüller, Benjamin

    2014-01-01

    Background Proper malaria diagnosis depends on the detection of asexual forms of Plasmodium spp. in the blood. Thick blood smear microscopy is the accepted gold standard of malaria diagnosis and is widely implemented. Surprisingly, diagnostic performance of this method is not well investigated and many clinicians in African routine settings base treatment decisions independent of microscopy results. This leads to overtreatment and poor management of other febrile diseases. Implementation of q...

  19. Simultaneous topography-guided PRK followed by corneal collagen cross-linking after lamellar keratoplasty for keratoconus

    Directory of Open Access Journals (Sweden)

    Spadea L

    2012-11-01

    Full Text Available Leopoldo Spadea,1 Marino Paroli21University of L’Aquila, Department of Biotechnological and Applied Clinical Sciences, Eye Clinic, L’Aquila, 2La Sapienza University, Department of Biotechnology and Medical-Surgical Sciences, Latina, ItalyBackground: The purpose of this paper is to report the results of using combined treatment of customized excimer laser-assisted photorefractive keratectomy (PRK and prophylactic corneal collagen crosslinking (CXL for residual refractive error in a group of patients who had previously undergone lamellar keratoplasty for keratoconus.Methods: The study included 14 eyes from 14 patients who had originally been treated for keratoconus in one eye by excimer laser-assisted lamellar keratoplasty (ELLK, and subsequently presented with residual ametropia (-6.11 D ± 2.48, range -2.50 to -9.50. After a mean 40.1 ± 12.4 months since ELLK they underwent combined simultaneous corneal regularization treatment with topographically guided transepithelial excimer laser PRK (central corneal regularization and corneal CXL induced by riboflavin-ultraviolet A.Results: After a mean 15 ± 6.5 (range 6–24 months, all eyes gained at least one Snellen line of uncorrected distance visual acuity (range 1–10. No patient lost lines of corrected distance visual acuity, and four patients gained three lines of corrected distance visual acuity. Mean manifest refractive spherical equivalent was -0.79 ± 2.09 (range +1 to -3.0 D, and topographic keratometric astigmatism was 5.02 ± 2.93 (range 0.8–8.9 D. All the corneas remained clear (haze < 1.Conclusion: The combination of customized PRK and corneal CXL provided safe and effective results in the management of corneal regularization for refractive purposes after ELLK for keratoconus.Keywords: corneal collagen crosslinking, excimer laser-assisted lamellar keratoplasty, photorefractive keratectomy

  20. Peptide Amphiphiles in Corneal Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Martina Miotto

    2015-08-01

    Full Text Available The increasing interest in effort towards creating alternative therapies have led to exciting breakthroughs in the attempt to bio-fabricate and engineer live tissues. This has been particularly evident in the development of new approaches applied to reconstruct corneal tissue. The need for tissue-engineered corneas is largely a response to the shortage of donor tissue and the lack of suitable alternative biological scaffolds preventing the treatment of millions of blind people worldwide. This review is focused on recent developments in corneal tissue engineering, specifically on the use of self-assembling peptide amphiphiles for this purpose. Recently, peptide amphiphiles have generated great interest as therapeutic molecules, both in vitro and in vivo. Here we introduce this rapidly developing field, and examine innovative applications of peptide amphiphiles to create natural bio-prosthetic corneal tissue in vitro. The advantages of peptide amphiphiles over other biomaterials, namely their wide range of functions and applications, versatility, and transferability are also discussed to better understand how these fascinating molecules can help solve current challenges in corneal regeneration.

  1. Corneal proteoglycan changes under vitamin A deficiency

    International Nuclear Information System (INIS)

    The vitamin A-deficient keratinized cornea is very susceptible to ulceration possibly due to altered stromal components. In this study the proteoglycans present in the corneal stroma of vitamin A-deficient, pair-fed and normal rabbits were compared. Rabbits after weaning were placed on a vitamin A deficient diet, the same diet with retinyl palmitate added (pair-fed) or normal rabbit chow. After 5 months, the corneas of the vitamin A-deficient animals became keratinized. The corneal components were then labeled by injection of 3H-leucine and Na35SO4 into the anterior chamber of the eyes on 3 successive days. On the 4th day the animals were sacrificed the corneas removed and dissected. The labeled corneal stromas were extracted with 4 M GuHCl and the components separated on a DEAE-Sepharose column. The proteoglycans were eluted with 0.5 M and 1.0 M NaCl. The 1.0 M NaCl fraction (mainly keratin sulfate proteoglycans) was increased 25% in the vitamin A-deficient corneas over that for the pair-fed and normal corneas. These proteoglycans from the deficient corneas gave a different elution pattern on Octyl-Sepharose eluted with a Triton X-100 gradient than those from the pair-fed corneas. The total labeled proteoglycans were similar in the stromas from the 3 types of rabbits. These results indicate the various corneal proteoglycan ratios differ under vitamin A deficiency conditions

  2. Past and present of corneal refractive surgery

    DEFF Research Database (Denmark)

    Vestergaard, Anders Højslet

    Surgical correction of refractive errors is becoming increasingly popular. In the 1990s, the excimer laser revolutionized the field of corneal refractive surgery with PRK and LASIK, and lately refractive lenticule extraction (ReLEx) of intracorneal tissue, using only a femtosecond laser, has become...

  3. Ultraviolet induced lysosome activity in corneal epithelium

    International Nuclear Information System (INIS)

    A 5.000 W Xe-Hg high pressure lamp and a double monochromator were used to produce a 3.3 nm half-bandpass ultraviolet radiation at 295 nm. Pigmented rabbit eyes were irradiated with radiant exposures from 140 Jm-2 to 10.000 Jm-2 and evaluated by slit-lamp biomicroscopy, light and electron microscopy. Corneal threshold (Hsub(c) was 200 Jm-2 and lens threshold (Hsub(L)) was 7.500 Jm-2. The most repeatable and reliable corneal response to these levels of UV was the development of corneal epithelial granules. Histological changes included a loss of superficial epithelial cells and selective UV induced autolysis of the wing cells. It is suggested that the biomicroscopically observed granules are the clinical manifestation of the secondary lysosomes revealed by light and electron microscopy. It is proposed that UV breaks down the primary lysosome membranes to release hydrolytic enzymes which in turn form the secondary lysosomes during autolysis. Extreme levels of radiant exposure at 295 nm result in indiscriminate destruction of all layers of the corneal epithelium, but the posterior cornea was spared. (orig.)

  4. [Future Innovative Medicine for Corneal Diseases].

    Science.gov (United States)

    Nishida, Kohji

    2016-03-01

    Japan faces an aging population and a declining birth rate, so medical professionals and the public are seeking next-generation ophthalmological treatments to preserve and restore visual function. Two fields lie at the heart of this future concept of ophthalmological treatments. The first is predictive medicine and early intervention and treatment. This field is based on precision medicine to treat chronic conditions such as keratoconus, glaucoma, and macular degeneration while the condition is latent or soon after it has developed. The second field is regenerative therapy. This field includes cell therapy, regenerative medicine, artificial corneas and retinal implants. Precision medicine is the concept of examining the effects of genomic information and environmental factors on the onset or progression of a condition. Precision medicine involves dividing patients with a given condition into subgroups and then developing an appropriate method of preventing or treating that condition for each group. This may prove useful in treating corneal conditions such as keratoconus and dry eye. To accomplish that goal, however, overarching genomic, imaging, and biomarker studies must be conducted. Markers related to the onset or progression of a condition must also be identified. This paper describes results of preliminary study of 2 types of markers: biomarkers, and genetic markers. These markers have been used in efforts to predict the onset or progression of keratoconus. The development of regenerative medicine requires basic studies of stem cells and microenvironments (niches) in which to sustain those cells. N-cadherin is a cell adhesion molecule, and the current authors are the first to contend that this molecule plays an important role in the corneal epithelial stem cell niche. In addition, the current authors are the first to report that corneal endothelial cells expressing p75 may potentially be corneal endothelial precursor cells. Capitalizing on the results of that

  5. Oxygen-deficient metabolism and corneal edema.

    Science.gov (United States)

    Leung, B K; Bonanno, J A; Radke, C J

    2011-11-01

    Wear of low-oxygen-transmissible soft contact lenses swells the cornea significantly, even during open eye. Although oxygen-deficient corneal edema is well-documented, a self-consistent quantitative prediction based on the underlying metabolic reactions is not available. We present a biochemical description of the human cornea that quantifies hypoxic swelling through the coupled transport of water, salt, and respiratory metabolites. Aerobic and anaerobic consumption of glucose, as well as acidosis and pH buffering, are incorporated in a seven-layer corneal model (anterior chamber, endothelium, stroma, epithelium, postlens tear film, contact lens, and prelens tear film). Corneal swelling is predicted from coupled transport of water, dissolved salts, and especially metabolites, along with membrane-transport resistances at the endothelium and epithelium. At the endothelium, the Na+/K+ - ATPase electrogenic channel actively transports bicarbonate ion from the stroma into the anterior chamber. As captured by the Kedem-Katchalsky membrane-transport formalism, the active bicarbonate-ion flux provides the driving force for corneal fluid pump-out needed to match the leak-in tendency of the stroma. Increased lactate-ion production during hypoxia osmotically lowers the pump-out rate requiring the stroma to swell to higher water content. Concentration profiles are predicted for glucose, water, oxygen, carbon dioxide, and hydronium, lactate, bicarbonate, sodium, and chloride ions, along with electrostatic potential and pressure profiles. Although the active bicarbonate-ion pump at the endothelium drives bicarbonate into the aqueous humor, we find a net flux of bicarbonate ion into the cornea that safeguards against acidosis. For the first time, we predict corneal swelling upon soft-contact-lens wear from fundamental biophysico-chemical principles. We also successfully predict that hypertonic tear alleviates contact-lens-induced edema. PMID:21820076

  6. Comparative results of corneal curvature measurements with three different keratometers after radial keratotomy

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lu; ZHANG Li; WANG Yan-ling; WANG Wei; YAN Yan

    2011-01-01

    Background Corneal curvatures measured by conventional instruments after refractive surgeries were greater than the real values.This study on the instruments and methods for measuring corneal curvature was carried out with the aim of determining an accurate,simple and effective method to evaluate corneal refractive power after radial keratotomy (RK).Methods A retrospective study was carried out on 52 eyes of 42 patients with a history of RK.The postoperative measurements after RK were performed with a manual keratometer (Rodenstock,Munchen-Hamburg,Germany),a corneal topographer (Tomey TMS-1) and an automated IOLMaster keratometer (Carl Zeiss GmbH,USA).The results obtained from analyzing clinical histories (clinical history method,CHM) were compared to the postoperative measurements with a two-way analysis of variance.Adjusted keratometry was used to correct the corneal central refractive power (K) values of the three keratometers.The CHM results were also compared to the corrected K values obtained with the three keratometers using the same statistical method.Results The smallest mean value was found for the CHM ((36.61±9.23) diopters).The K values obtained with the CHM were very different from the results obtained with the three different instruments.The corrected K values obtained with the IOLMaster were the closest to the K values from the CHM.Conclusions It was shown that K values from measurements with the three instruments were higher.When the power of the intraocular lens of the patients after RK was calculated,the errors of the K values measured with the instruments should be taken into consideration.

  7. Effect of chemical composition on corneal tissue response to photopolymerized materials comprising 2-hydroxyethyl methacrylate and acrylic acid

    International Nuclear Information System (INIS)

    The purpose of this work was to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/acrylic acid (AAc) and hydrogel material compatibility towards ocular anterior segment tissues, particularly the corneal endothelium. The monomer solutions of HEMA and AAc were mixed at varying volume ratios of 92:0, 87:5, 82:10, 77:15, and 72:20, and were subjected to UV irradiation. Then, the 7-mm-diameter membrane implants made from photopolymerized materials were placed into the ocular anterior chamber for 4 days and assessed by biomicroscopic examinations, corneal thickness measurements, and quantitative real-time reverse transcription polymerase chain reaction analyses. The poly(HEMA-co-AAc) implants prepared from the solution mixture containing 0–10 vol.% AAc displayed good biocompatibility. However, with increasing volume ratio of AAc and HEMA from 15:77 to 20:72, the enhanced inflammatory response, decreased endothelial cell density, and increased ocular score and corneal thickness were observed, probably due to the influence of surface charge of copolymer membranes. On the other hand, the ionic pump function of corneal endothelium exposed to photopolymerized membranes was examined by analyzing the Na+,K+-ATPase alpha 1 subunit (ATP1A1) expression level. The presence of the implants having higher amount of AAc incorporated in the copolymers (i.e., 15.1 to 24.7 μmol) and zeta potential (i.e., -38.6 to − 56.5 mV) may lead to abnormal transmembrane transport. It is concluded that the chemical composition of HEMA/AAc has an important influence on the corneal tissue responses to polymeric biomaterials. - Highlights: • We examine the corneal tissue responses to photopolymerized biomaterials. • Carboxyl groups in copolymers increased with increasing volume ratio of AAc/HEMA. • 15–20 vol.% AAc raised ocular score and caused corneal endothelial loss and edema. • High anionic charge density stimulated inflammation and

  8. Effect of chemical composition on corneal tissue response to photopolymerized materials comprising 2-hydroxyethyl methacrylate and acrylic acid

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Jui-Yang, E-mail: jylai@mail.cgu.edu.tw

    2014-01-01

    The purpose of this work was to investigate the relationship between the feed composition of 2-hydroxyethyl methacrylate (HEMA)/acrylic acid (AAc) and hydrogel material compatibility towards ocular anterior segment tissues, particularly the corneal endothelium. The monomer solutions of HEMA and AAc were mixed at varying volume ratios of 92:0, 87:5, 82:10, 77:15, and 72:20, and were subjected to UV irradiation. Then, the 7-mm-diameter membrane implants made from photopolymerized materials were placed into the ocular anterior chamber for 4 days and assessed by biomicroscopic examinations, corneal thickness measurements, and quantitative real-time reverse transcription polymerase chain reaction analyses. The poly(HEMA-co-AAc) implants prepared from the solution mixture containing 0–10 vol.% AAc displayed good biocompatibility. However, with increasing volume ratio of AAc and HEMA from 15:77 to 20:72, the enhanced inflammatory response, decreased endothelial cell density, and increased ocular score and corneal thickness were observed, probably due to the influence of surface charge of copolymer membranes. On the other hand, the ionic pump function of corneal endothelium exposed to photopolymerized membranes was examined by analyzing the Na{sup +},K{sup +}-ATPase alpha 1 subunit (ATP1A1) expression level. The presence of the implants having higher amount of AAc incorporated in the copolymers (i.e., 15.1 to 24.7 μmol) and zeta potential (i.e., -38.6 to − 56.5 mV) may lead to abnormal transmembrane transport. It is concluded that the chemical composition of HEMA/AAc has an important influence on the corneal tissue responses to polymeric biomaterials. - Highlights: • We examine the corneal tissue responses to photopolymerized biomaterials. • Carboxyl groups in copolymers increased with increasing volume ratio of AAc/HEMA. • 15–20 vol.% AAc raised ocular score and caused corneal endothelial loss and edema. • High anionic charge density stimulated inflammation

  9. Cellular and extracellular matrix modulation of corneal stromal opacity.

    Science.gov (United States)

    Torricelli, Andre A M; Wilson, Steven E

    2014-12-01

    Stromal transparency is a critical factor contributing to normal function of the visual system. Corneal injury, surgery, disease and infection elicit complex wound healing responses that serve to protect against insults and maintain the integrity of the cornea, and subsequently to restore corneal structure and transparency. However, in some cases these processes result in prolonged loss of corneal transparency and resulting diminished vision. Corneal opacity is mediated by the complex actions of many cytokines, growth factors, and chemokines produced by the epithelial cells, stromal cells, bone marrow-derived cells, lacrimal tissues, and nerves. Myofibroblasts, and the disorganized extracellular matrix produced by these cells, are critical determinants of the level and persistence of stromal opacity after corneal injury. Decreases in corneal crystallins in myofibroblasts and corneal fibroblasts contribute to cellular opacity in the stroma. Regeneration of a fully functional epithelial basement membrane (BM) appears to have a critical role in the maintenance of corneal stromal transparency after mild injuries and recovery of transparency when opacity is generated after severe injuries. The epithelial BM likely has a regulatory function whereby it modulates epithelium-derived growth factors such as transforming growth factor (TGF) β and platelet-derived growth factor (PDGF) that drive the development and persistence of myofibroblasts from precursor cells. The purpose of this article is to review the factors involved in the maintenance of corneal transparency and to highlight the mechanisms involved in the appearance, persistency and regression of corneal opacity after stromal injury. PMID:25281830

  10. Emodin ameliorates lipopolysaccharides-induced corneal inflammation in rats

    Institute of Scientific and Technical Information of China (English)

    Guo-Ling; Chen; Jing-Jing; Zhang; Xin; Kao; Lu-Wan; Wei; Zhi-Yu; Liu

    2015-01-01

    · AIM: To investigate the effect of emodin on pseudomonas aeruginosa lipopolysaccharides(LPS)-induced corneal inflammation in rats.· METHODS: Corneal infection was induced by pseudomonas aeruginosa LPS in Wistar rats. The inflammation induced by LPS were examined by slit lamp microscope and cytological checkup of aqueous humor.Corneal tissue structure was observed by hematoxylin and eosin(HE) staining. The activation of nuclear factor kappa B(NF-κB) was determined by Western blot.Messenger ribonucleic acid(m RNA) of tumor necrosis factor-α(TNF-α) and intercellular adhesion molecule-1(ICAM-1) in LPS-challenged rat corneas were measured with reverse transcription-polymerase chain reaction(RT-PCR).· RESULTS: Typical manifestations of acute corneal inflammation were observed in LPS-induce rat model,and the corneal inflammatory response and structure were improved in rats pretreated with emodin. Treatment with emodin could improve corneal structure, reduce corneal injure by reducing corneal inflammatory response. Emodin could inhibit the decreasing lever of inhibitor of kappa B alpha(IкBα) express, and the m RNA expression of TNF-α and ICAM-1 in corneal tissues was also inhibited by emodin. The differences were statistically significant between groups treated with emodin and those without treatment(P <0.01).·CONCLUSION: Emodin could ameliorate LPS-induced corneal inflammation, which might via inhibiting the activation of NF-κB.

  11. A novel proteotoxic stress associated mechanism for macular corneal dystrophy.

    Science.gov (United States)

    Kaarniranta, Kai; Szalai, Eszter; Smedowski, Adrian; Hegyi, Zoltán; Kivinen, Niko; Viiri, Johanna; Wowra, Bogumil; Dobrowolski, Dariusz; Módis, László; Berta, András; Wylegala, Edward; Felszeghy, Szabolcs

    2015-08-01

    Macular corneal dystrophy is a rare autosomal recessive eye disease affecting primarily the corneal stroma. Abnormal accumulation of proteoglycan aggregates has been observed intra- and extracellularly in the stromal layer. In addition to the stromal keratocytes and corneal lamellae, deposits are also present in the basal epithelial cells, endothelial cells and Descemet's membrane. Misfolding of proteins has a tendency to gather into aggregating deposits. We studied interaction of molecular chaperones and proteasomal clearance in macular dystrophy human samples and in human corneal HCE-2 epithelial cells. Seven cases of macular corneal dystrophy and four normal corneal buttons collected during corneal transplantation were examined for their expression patterns of heat shock protein 70, ubiquitin protein conjugates and SQSTM1/p62. In response to proteasome inhibition the same proteins were analyzed by western blotting. Slit-lamp examination, in vivo confocal cornea microscopy and transmission electron microscopy were used for morphological analyses. Heat shock protein 70, ubiquitin protein conjugates and SQSTM1/p62 were upregulated in both the basal corneal epithelial cells and the stromal keratocytes in macular corneal dystrophy samples that coincided with an increased expression of the same molecules under proteasome inhibition in the HCE-2 cells in vitro. We propose a novel regulatory mechanism that connects the molecular chaperone and proteasomal clearance system in the pathogenesis of macular corneal dystrophy. PMID:25597745

  12. Electrospun Scaffolds for Corneal Tissue Engineering: A Review

    Directory of Open Access Journals (Sweden)

    Bin Kong

    2016-07-01

    Full Text Available Corneal diseases constitute the second leading cause of vision loss and affect more than 10 million people globally. As there is a severe shortage of fresh donated corneas and an unknown risk of immune rejection with traditional heterografts, it is very important and urgent to construct a corneal equivalent to replace pathologic corneal tissue. Corneal tissue engineering has emerged as a practical strategy to develop corneal tissue substitutes, and the design of a scaffold with mechanical properties and transparency similar to that of natural cornea is paramount for the regeneration of corneal tissues. Nanofibrous scaffolds produced by electrospinning have high surface area–to-volume ratios and porosity that simulate the structure of protein fibers in native extra cellular matrix (ECM. The versatilities of electrospinning of polymer components, fiber structures, and functionalization have made the fabrication of nanofibrous scaffolds with suitable mechanical strength, transparency and biological properties for corneal tissue engineering feasible. In this paper, we review the recent developments of electrospun scaffolds for engineering corneal tissues, mainly including electrospun materials (single and blended polymers, fiber structures (isotropic or anisotropic, functionalization (improved mechanical properties and transparency, applications (corneal cell survival, maintenance of phenotype and formation of corneal tissue and future development perspectives.

  13. Ciliary neurotrophic factor promotes the activation of corneal epithelial stem/progenitor cells and accelerates corneal epithelial wound healing.

    Science.gov (United States)

    Zhou, Qingjun; Chen, Peng; Di, Guohu; Zhang, Yangyang; Wang, Yao; Qi, Xia; Duan, Haoyun; Xie, Lixin

    2015-05-01

    Ciliary neurotrophic factor (CNTF), a well-known neuroprotective cytokine, has been found to play an important role in neurogenesis and functional regulations of neural stem cells. As one of the most innervated tissue, however, the role of CNTF in cornea epithelium remains unclear. This study was to explore the roles and mechanisms of CNTF in the activation of corneal epithelial stem/progenitor cells and wound healing of both normal and diabetic mouse corneal epithelium. In mice subjecting to mechanical removal of corneal epithelium, the corneal epithelial stem/progenitor cell activation and wound healing were promoted by exogenous CNTF application, while delayed by CNTF neutralizing antibody. In cultured corneal epithelial stem/progenitor cells, CNTF enhanced the colony-forming efficiency, stimulated the mitogenic proliferation, and upregulated the expression levels of corneal epithelial stem/progenitor cell-associated transcription factors. Furthermore, the promotion of CNTF on the corneal epithelial stem/progenitor cell activation and wound healing was mediated by the activation of STAT3. Moreover, in diabetic mice, the content of CNTF in corneal epithelium decreased significantly when compared with that of normal mice, and the supplement of CNTF promoted the diabetic corneal epithelial wound healing, accompanied with the advanced activation of corneal epithelial stem/progenitor cells and the regeneration of corneal nerve fibers. Thus, the capability of expanding corneal epithelial stem/progenitor cells and promoting corneal epithelial wound healing and nerve regeneration indicates the potential application of CNTF in ameliorating limbal stem cell deficiency and treating diabetic keratopathy. PMID:25546438

  14. Unilateral corneal leukoplakia without limbal involvement

    Directory of Open Access Journals (Sweden)

    Hirano K

    2015-05-01

    Full Text Available Koji Hirano,1 Mihoko Koide,2 Yoshikazu Mizoguchi,3 Yasuhiro Osakabe,4 Kaoru-Araki Sasaki5 1Department of Ophthalmology, Ban Buntane Hotokukai Hospital, School of Medicine, Fujita Health University, Nagoya, Japan; 2Koide Internal Medicine and Eye Clinic, Nagoya, Japan; 3Department of Pathology, Ban Buntane Hotokukai Hospital, School of Medicine, Fujita Health University, Nagoya, Japan; 4Department of Molecular Pathology, Tokyo Medical University, Tokyo, Japan; 5Department of Ophthalmology, Japan Health Care Organization, Hoshigaoka Medical Center, Hirakata, Japan Purpose: Leukoplakia is the term given to a white patch or plaque that is found mainly on the oral mucus membrane. It can occasionally be seen on the corneal surface. We report our clinical and histopathological findings in a case of unilateral corneal leukoplakia. Methods: A 26-year-old woman was referred to our hospital because of a white patch on her right cornea that continued to expand. She first noticed the white patch when she was 20 years old, and the white patch had expanded to cover the pupillary area affecting her vision. After plastic surgery on both eyelids for bilateral entropion to alleviate the pain caused by the eyelashes rubbing the cornea, the white corneal patch decreased in size. Because of this reduction, we performed surgery to remove the patch with microforceps under topical anesthesia. The plaque was removed easily and completely, and submitted for histopathological examination. Results: Histopathological examination showed that the specimen had characteristics of epidermis with a basal cell layer, spinous cell layer, granular cell layer, and horny layer with hyperkeratosis. She was diagnosed with leukoplakia of the corneal surface. The basic structure of the squamous cell layer was preserved, and there were no signs of metaplasia. Six months after the removal of the leukoplakia, no recurrence was seen and her corrected decimal visual acuity recovered to 1

  15. Dextran Preserves Native Corneal Structure During Decellularization.

    Science.gov (United States)

    Lynch, Amy P; Wilson, Samantha L; Ahearne, Mark

    2016-06-01

    Corneal decellularization has become an increasingly popular technique for generating scaffolds for corneal regeneration. Most decellularization procedures result in tissue swelling, thus limiting their application. Here, the use of a polysaccharide, dextran, to reduce swelling and conserve the native corneal structure during decellularization was investigated. Corneas were treated with 1% Triton X-100, 0.5% sodium dodecyl sulfate, and nucleases under constant rotation followed by extensive washing. To reduce swelling, decellularization solutions were supplemented with 5% dextran either throughout the whole decellularization process or during the washing cycles only. Quantitative analysis of DNA content showed a 96% reduction after decellularization regardless of the addition of dextran. Dextran resulted in a significant reduction in swelling from 3.85 ± 0.43 nm without to 1.94 ± 0.29-2.01 ± 0.37 nm (p native tissue (1.73 ± 0.23 nm). Tissue transparency was restored to all decellularized corneas following submersion in glycerol. Transmission electron microscopy (TEM) analysis found that dextran must be present throughout the decellularization protocol to preserve the native corneal architecture, anisotropy analysis demonstrated comparable results (0.22 ± 0.03) to the native cornea (0.24 ± 0.02), p > 0.05. Dextran can counteract the detrimental effects of decellularizing agents on the biomechanical properties of the tissue resulting in similar compressive moduli (mean before decellularization: 5.40 ± 1.18 kPa; mean after decellularization with dextran: 5.64 ± 1.34 kPa, p > 0.05). Cells remained viable in the presence of decellularized scaffolds. The findings of this study indicate that dextran not only prevents significant corneal swelling during decellularization but also enhances the maintenance of the native corneal ultrastructure. PMID:27068608

  16. Corneal Graft Rejection: Incidence and Risk Factors

    Directory of Open Access Journals (Sweden)

    Alireza Baradaran-Rafii

    2008-12-01

    Full Text Available

    PURPOSE: To determine the incidence and risk factors of late corneal graft rejection after penetrating keratoplasty (PKP. METHODS: Records of all patients who had undergone PKP from 2002 to 2004 without immunosuppressive therapy other than systemic steroids and with at least one year of follow up were reviewed. The role of possible risk factors such as demographic factors, other host factors, donor factors, indications for PKP as well as type of rejection were evaluated. RESULTS: During the study period, 295 PKPs were performed on 286 patients (176 male, 110 female. Mean age at the time of keratoplasty was 38±20 (range, 40 days to 90 years and mean follow up period was 20±10 (range 12-43 months. Graft rejection occurred in 94 eyes (31.8% at an average of 7.3±6 months (range, 20 days to 39 months after PKP. The most common type of rejection was endothelial (20.7%. Corneal vascularization, regrafting, anterior synechiae, irritating sutures, active inflammation, additional anterior segment procedures, history of trauma, uncontrolled glaucoma, prior graft rejection, recurrence of herpetic infection and eccentric grafting increased the rate of rejection. Patient age, donor size and bilateral transplantation had no significant influence on graft rejection. CONCLUSION: Significant risk factors for corneal graft rejection include

  17. Effects of aberrant Pax6 gene dosage on mouse corneal pathophysiology and corneal epithelial homeostasis.

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    Richard L Mort

    Full Text Available Altered dosage of the transcription factor PAX6 causes multiple human eye pathophysiologies. PAX6⁺/⁻ heterozygotes suffer from aniridia and aniridia-related keratopathy (ARK, a corneal deterioration that probably involves a limbal epithelial stem cell (LESC deficiency. Heterozygous Pax6(+/Sey-Neu (Pax6⁺/⁻ mice recapitulate the human disease and are a good model of ARK. Corneal pathologies also occur in other mouse Pax6 mutants and in PAX77(Tg/- transgenics, which over-express Pax6 and model human PAX6 duplication.We used electron microscopy to investigate ocular defects in Pax6⁺/⁻ heterozygotes (low Pax6 levels and PAX77(Tg/- transgenics (high Pax6 levels. As well as the well-documented epithelial defects, aberrant Pax6 dosage had profound effects on the corneal stroma and endothelium in both genotypes, including cellular vacuolation, similar to that reported for human macular corneal dystrophy. We used mosaic expression of an X-linked LacZ transgene in X-inactivation mosaic female (XLacZ(Tg/- mice to investigate corneal epithelial maintenance by LESC clones in Pax6⁺/⁻ and PAX77(Tg/- mosaic mice. PAX77(Tg/- mosaics, over-expressing Pax6, produced normal corneal epithelial radial striped patterns (despite other corneal defects, suggesting that centripetal cell movement was unaffected. Moderately disrupted patterns in Pax6⁺/⁻ mosaics were corrected by introducing the PAX77 transgene (in Pax6⁺/⁻, PAX77(Tg/- mosaics. Pax6(Leca4/+, XLacZ(Tg/- mosaic mice (heterozygous for the Pax6(Leca4 missense mutation showed more severely disrupted mosaic patterns. Corrected corneal epithelial stripe numbers (an indirect estimate of active LESC clone numbers declined with age (between 15 and 30 weeks in wild-type XLacZ(Tg/- mosaics. In contrast, corrected stripe numbers were already low at 15 weeks in Pax6⁺/⁻ and PAX77(Tg/- mosaic corneas, suggesting Pax6 under- and over-expression both affect LESC clones.Pax6⁺/⁻ and PAX77(Tg

  18. Customized pachymetric guided epithelial debridement for corneal collagen cross linking

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    Jankov Mirco

    2009-08-01

    Full Text Available Abstract Backround We describe a modified method for deepitheliazation prior to corneal cross linking (CXL. The technique may overcome the current corneal pachymetric limitation parameter (over 400 microns that is necessary for the safety of the procedure without affecting the overall benefits. Methods In a series of two patients, with inferior topographic steepening and regional thinning (less than 400 microns corresponding to the area of corneal steepening, CXL after customized epithelial removal was performed. Results There were no intra- or postoperative adverse events seen by the nine month follow up examination. Stabilization of the corneal ectasia was observed up to nine months post-costumized pachymetric-guided epithelial removal. Conclusion The technique of customized pachymetric-guided epithelial removal is easy to perform and may overcome the limitations of the preoperative corneal pachymetry expanding the application of the procedure in patients with regional corneal thinning.

  19. Evaluation of retinal nerve fiber layer thickness measurement following laser in situ keratomileusis using scanning laser polarimetry

    OpenAIRE

    Dada Tanuj; Chaudhary Sunil; Muralidhar Rajamani; Nair Soman; Sihota Ramanjit; Vajpayee Rasik

    2007-01-01

    Aim: To evaluate the effect of laser-assisted in situ keratomileusis (LASIK) on the measurement of retinal nerve fiber layer thickness by scanning laser polarimetry using customized corneal compensation in myopes. Materials and Methods: Scanning laser polarimetry was performed on 54 eyes of 54 healthy patients with myopia using the glaucoma diagnostics variable corneal compensation (GDx VCC) instrument (Laser Diagnostic Technologies, San Diego, California) before and a week after LASIK. ...

  20. Induction of corneal collagen cross-linking in experimental corneal alkali burns in rabbits

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    Marcello Colombo-Barboza

    2014-10-01

    Full Text Available Objective: To evaluate the effect of riboflavin-ultraviolet-A-induced cross-linking (CXL following corneal alkali burns in rabbits. Methods: The right corneas and limbi of ten rabbits were burned using a 1N solution of NaOH and the animals were then divided into two groups: a control group submitted to clinical treatment alone and an experimental group that was treated 1 h after injury with CXL, followed by the same clinical treatment as administered to the controls. Clinical parameters were evaluated post-injury at 1, 7, 15, and 30 days by two independent observers. Following this evaluation, the corneas were excised and examined histologically. Results: There were no statistically significant differences in clinical parameters, such as hyperemia, corneal edema, ciliary injection, limbal ischemia, secretion, corneal neovascularization, symblepharon, or blepharospasm, at any of the time-points evaluated. However, the size of the epithelial defect was significantly smaller in the CXL group (p<0.05 (day 15: p=0.008 and day 30: p=0.008 and the extent of the corneal injury (opacity lesion was also smaller (day 30: p=0.021. Histopathology showed the presence of collagen bridges linking the collagen fibers in only the CXL group. Conclusions: These results suggest that the use of CXL may improve the prognosis of acute corneal alkali burns.

  1. Development of an algorithm for corneal reshaping with a scanning laser beam

    Science.gov (United States)

    Shen, Jin-Hui; Söderberg, Per; Matsui, Takaaki; Manns, Fabrice; Parel, Jean-Marie

    1995-07-01

    The corneal-ablation rate, the beam-intensity distribution, and the initial and the desired corneal topographies are used to calculate a spatial distribution map of laser pulses. The optimal values of the parameters are determined with a computer model, for a system that produces 213-nm radiation with a Gaussian beam-intensity distribution and a peak radiant exposure of 400 mJ/cm2. The model shows that with a beam diameter of 0.5 mm, an overlap of 80%, and a 5-mm treatment zone, the roughness is less than 6% of the central ablation depth, the refractive error after correction is less than 0.1 D for corrections of myopia of 1, 3, and 6 D and less than 0.4 D for a correction of myopia of 10 D, and the number of pulses per diopter of

  2. PRE OPERATIVE CORNEAL ASTIGMATISM IN PATIENTS WITH CATARACT

    OpenAIRE

    Venkateswara Rao; Hanumantha Rao; Sivacharan; Anitha Devi

    2015-01-01

    AIM: To determine corneal astigmatism in patients with cataract posted for surgery. To achieve good visual outcome, significant corneal astigmatism has to be taken care of at the time of surgery either by corneal or limba l relaxing incisions or by implantation of toric intraocular lens. MATERIALS AND METHODS: This is a prospective observational case series conducted on 200 patients with cataract who attended the out - patient department of ophthalmology and c...

  3. Corneal Tissue Engineering: Recent Advances and Future Perspectives

    OpenAIRE

    Ghezzi, Chiara E.; Rnjak-Kovacina, Jelena; Kaplan, David L

    2015-01-01

    To address the growing need for corneal transplants two main approaches are being pursued: allogenic and synthetic materials. Allogenic tissue from human donors is currently the preferred choice; however, there is a worldwide shortage in donated corneal tissue. In addition, tissue rejection often limits the long-term success of this approach. Alternatively, synthetic homologs to donor corneal grafts are primarily considered temporary replacements until suitable donor tissue becomes available,...

  4. Experimental study on cryotherapy for fungal corneal ulcer

    OpenAIRE

    Chen, Yingxin; Yang, Weijia; Gao, Minghong; Belin, Michael Wellington; Yu, Hai; Yu, Jing

    2015-01-01

    Background Fungal corneal ulcer is one of the major causes of visual impairment worldwide. Treatment of fungal corneal ulcer mainly depends on anti-fungal agents. In the current study, we developed an integrated combination therapy of cryotherapy and anti-fungal agents to facilitate effective treatment of fungal corneal ulcer. Methods Rabbit models of cornea infection were established using a combined method of intrastromal injection and keratoplasty. After treatment with cryotherapy and anti...

  5. Sands of Sahara after LASIK in Avellino Corneal Dystrophy

    OpenAIRE

    Flavio Mantelli; Alessandro Lambiase; Antonio Di Zazzo; Stefano Bonini

    2012-01-01

    We report the case of a patient diagnosed with Avellino corneal dystrophy (ACD) who developed diffuse interstitial keratitis following excimer laser insitu keratomileusis (LASIK). ACD is an autosomal dominant corneal dystrophy characterized by multiple asymmetric stromal opacities that impair vision. Accepted treatments for this condition include corneal transplantation and phototherapeutic keratectomy (PTK). Our patient underwent LASIK at another institution to correct myopia. LASIK and phot...

  6. Corneal irregular astigmatism after laser in situ keratomileusis for myopia

    OpenAIRE

    Baek, T. M.; K. H. Lee; Tomidokoro, A; Oshika, T

    2001-01-01

    AIMS—To quantitatively evaluate the changes in corneal irregular astigmatism after laser in situ keratomileusis (LASIK) in relation to the amount of laser ablation.
METHODS—In 189 eyes of 116 patients undergoing LASIK for myopia, corneal topography was obtained before and 1 month after surgery. Using Fourier harmonic analysis of the topography data, corneal irregular astigmatism (asymmetry and higher order irregularity) was calculated.
RESULTS—By surgery, asymmetry component significantly inc...

  7. EXPERIMENTAL STUDY ON THE CORNEAL ENDOTHELIUM OF TRAUMATIC CATARACT

    Institute of Scientific and Technical Information of China (English)

    1991-01-01

    The cell morphology of corneal endothelium in 84 mice with experimental traumatic cataract was investigated with stained corneal buttons. In the experimental group, the boundaries between adjacent corneal endothelial cells were significantly distorted, some cell boundaries manifested degenerative changes that led to coalescence of the cells. The mean density and mean area of endothelial cells of the controls showed significant difference from those of the experimental group during the 12 weeks of observ...

  8. Corneal Neovascularization: An Anti-VEGF Therapy Review

    OpenAIRE

    Chang, Jin-Hong; Garg, Nitin K.; Lunde, Elisa; Han, Kyu-Yeon; Jain, Sandeep; Azar, Dimitri T.

    2012-01-01

    Corneal neovascularization is a serious condition that can lead to a profound decline in vision. The abnormal vessels block light, cause corneal scarring, compromise visual acuity, and may lead to inflammation and edema. Corneal neovascularization occurs when the balance between angiogenic and antiangiogenic factors is tipped toward angiogenic molecules. Vascular endothelial growth factor (VEGF), one of the most important mediators of angiogenesis, is upregulated during neovascularization. In...

  9. Intrastromal injection of bevacizumab in patients with corneal neovascularization

    OpenAIRE

    Ana Carolina Cabreira Vieira; Ana Luisa Höfling-Lima; Gomes, José Álvaro P.; Denise de Freitas; Michel Eid Farah; Rubens Belfort Jr

    2012-01-01

    Corneal neovascularization (NV) not only reduces visual acuity, but it also causes loss of the cornea's immune privilege, strongly contributing to a worse prognosis in penetrating keratoplasty. Several mediators participate in corneal angiogenesis, and the role of vascular endothelial growth factor (VEGF) has been extensively proven. Anti-VEGF agents have been shown to be effective in slowing the growth of corneal neovessels. Bevacizumab, an anti-VEGF agent, has been successfully used in the ...

  10. Spontaneous corneal perforation in ocular rosacea.

    Science.gov (United States)

    Al Arfaj, Khalid; Al Zamil, Waseem

    2010-04-01

    Rosacea is a dermatologic condition that affects the midfacial region. Ocular rosacea is most frequently diagnosed when cutaneous signs and symptoms are also present. Ocular manifestations are essentially confined to the eyelids and ocular surface. Ocular involvement ranges from minor irritation, dryness, and blurry vision to potentially severe ocular surface disruption including corneal ulcers, vascularization and rarely perforation. We present a 49-year-old Saudi Arabian female with the diagnosis of rosacea who presented with a peripheral corneal performation. The perforation was successfully managed by surgical repair, oral doxycycline and topical steroid. The final best corrected visual acuity was 20/30 after treatment. Early referral to an ophthalmologist and careful long-term follow-up are recommended. PMID:20616930

  11. Spontaneous corneal perforation in ocular rosacea

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    Al Arfaj Khalid

    2010-01-01

    Full Text Available Rosacea is a dermatologic condition that affects the midfacial region. Ocular rosacea is most frequently diagnosed when cutaneous signs and symptoms are also present. Ocular manifestations are essentially confined to the eyelids and ocular surface. Ocular involvement ranges from minor irritation, dryness, and blurry vision to potentially severe ocular surface disruption including corneal ulcers, vascularization and rarely perforation. We present a 49-year-old Saudi Arabian female with the diagnosis of rosacea who presented with a peripheral corneal performation. The perforation was successfully managed by surgical repair, oral doxycycline and topical steroid. The final best corrected visual acuity was 20/30 after treatment. Early referral to an ophthalmologist and careful long-term follow-up are recommended.

  12. Corneal hymenoptera stings: A new therapeutic approach

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    Mauricio Vélez

    2012-12-01

    Full Text Available Purpose: We describe five cases, (4 children, with ocular sequelae from honeybee or wasp sting injuries to the eye treated with anterior chamber irrigation to reduce the venom concentration and subsequent complications. All patients were treated on the Ophthalmology Service of Hospital Universitario San Vicente de Paul, Medellín, Colombia. Methods: Small case series. Patients with hymenoptera corneal sting injuries were treated in the operating room by performing an anterior chamber washout with balanced saline solution and triamcinolone in an effort to minimize the tissue damage induced by bee venom. Results: Early clearing of inflammation and more rapid recovery of baseline acuity was associated with early surgical intervention. Late complications included corneal decompensation, iris heterochromia, paralytic mydriasis, glaucoma and cataract; these complications are irreversible and sight threatening. Conclusion: Performing an early anterior chamber washout is a treatment option for this type of trauma, since it results in faster resolution and fewer late complications. 

  13. Visual outcome of cataract surgery with pupillary sphincterotomy in eyes with coexisting corneal opacity

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    Vajpayee Rasik B

    2004-04-01

    Full Text Available Abstract Background To evaluate the visual outcome following cataract surgery with pupillary sphincterotomy in eyes with coexisting corneal opacity. Methods Patients with leucomatous corneal opacity with significant cataract were enrolled for the study. The uncorrected visual acuity and best-corrected visual acuity (BCVA were recorded and the anterior segment was thoroughly evaluated by a slit lamp biomicroscope before the surgery. Only those patients who had some amount of clear peripheral cornea were selected. Posterior segment pathology was ruled out by indirect ophthalmoscopy after pupillary dilatation, if possible, or by B-scan ultrasonography. Conventional extracapsular cataract extraction with pupillary sphincterotomy was performed and an intraocular lens was implanted. Postoperatively, the eyes were evaluated on day 1, and 1 week and 6 weeks following surgery for similar parameters. Results Fourteen eyes of 14 patients were included in the study, of which 13 (92.85% patients were male. The mean age of the patients was 47.85 ± 7.37 years. All the eyes had a dense central leucomatous corneal opacity. Twelve (85.71% eyes had two or more quadrants of deep vascularisation. Sphincterotomy was performed mostly (71.42% in the nasal or inferonasal quadrant. The intraocular lens was implanted in 13 (92.85% eyes, and one (7.1% eye was left aphakic due to the occurrence of a large posterior capsular tear. Preoperatively, all eyes had BCVA Conclusions Extracapsular cataract extraction and intraocular lens implantation with pupillary sphincterotomy provides ambulatory and useful vision to patients of cataract with coexisting central leucomatous corneal opacity.

  14. Analysis of correlation between corneal topographical data and visual performance

    Science.gov (United States)

    Zhou, Chuanqing; Yu, Lei; Ren, Qiushi

    2007-02-01

    Purpose: To study correlation among corneal asphericity, higher-order aberrations and visual performance for eyes of virgin myopia and postoperative laser in situ keratomileusis (LASIK). Methods: There were 320 candidates 590 eyes for LASIK treatment included in this study. The mean preoperative spherical equivalence was -4.35+/-1.51D (-1.25 to -9.75), with astigmatism less than 2.5 D. Corneal topography maps and contrast sensitivity were measured and analyzed for every eye before and one year after LASIK for the analysis of corneal asphericity and wavefront aberrations. Results: Preoperatively, only 4th and 6th order aberration had significant correlation with corneal asphericity and apical radius of curvature (p0.05). Postoperatively, corneal aberrations still didn't have significant correlation with visual acuity (P>0.05), but had significantly negative correlation with AULCSF (P0.05). Conclusions: Corneal aberrations had different correlation with corneal profile and visual performance for eyes of virgin myopia and postoperative LASIK, which may be due to changed corneal profile and limitation of metrics of corneal aberrations.

  15. Corneal Ectasis among Wrestlers: Report of Two Cases

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    Mohammad Ali Zare Mehrjardi

    2014-07-01

    Full Text Available Report keratoconus in two patients with a long history of wrestling without any risk factor for corneal ectasia and reviewing the possible pathogenesis. To confirm suspicion of keratoconus, corneal topography was performed using scanning slit topography system and Orbscan. In two wrestlers with the complaint of visual loss in their eyes and IOP raising, corneal topography was performed and development of keratoconus (KCN was detected. Athletes involved in sports with high strenuous exercises might need routine eye examination and also a baseline corneal topography. This may provide an earlier detection of KCN in this group of athletics.

  16. Clinical correlates of common corneal neovascular diseases: a literature review

    Institute of Scientific and Technical Information of China (English)

    Nizar; Saleh; Abdelfattah; Mohamed; Amgad; Amira; A; Zayed; Hamdy; Salem; Ahmed; E; Elkhanany; Heba; Hussein; Nawal; Abd; El-Baky

    2015-01-01

    A large subset of corneal pathologies involves the formation of new vessels(neovascularization), leading to compromised visual acuity. This article aims to review the clinical causes and presentations of corneal neovascularization(CNV) by examining the mechanisms behind common CNV-related corneal pathologies, with a particular focus on herpes simplex stromal keratitis,contact lenses-induced keratitis and CNV secondary to keratoplasty. Moreover, we reviewed CNV in the context of different types of corneal transplantation and keratoprosthesis, and summarized the most relevant treatment available so far.

  17. RECURRENT CORNEAL EROSION SYNDROME (a review

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    S. V. Trufanov

    2015-01-01

    Full Text Available Recurrent corneal erosion (RCE syndrome is characterized by episodes of recurrent spontaneous epithelial defects. Main clinical symptoms (pain, redness, photophobia, lacrimation occurred at night. Corneal lesions revealed by slit lamp exam vary depending on the presence of corneal epithelium raise, epithelial microcysts or epithelial erosions, stromal infiltrates and opacities. Microtraumas, anterior corneal dystrophies, and herpesvirus give rise to RCE. Other causes or factors which increase the risk of RCE syndrome include meibomian gland dysfunction, keratoconjunctivitis sicca, diabetes, and post-LASIK conditions. Basal membrane abnormalities and instability of epithelial adhesion to stroma play a key role in RCE pathogenesis. Ultrastructural changes in RCE include abnormalities of basal epithelial cells and epithelial basal membrane, absence or deficiency of semi-desmosomes, loss of anchor fibrils. Increase in matrix metalloproteinases and collagenases which contribute to basal membrane destruction results in recurrent erosions and further development of abnormal basal membrane. The goals of RCE therapy are to reduce pain (in acute stage, to stimulate re-epithelization, and to restore «adhesion complex» of basal membrane. In most cases, RCE responds to simple conservative treatment that includes lubricants, healing agents, and eye patches. RCEs that are resistant to simple treatment, require complex approach. Non-invasive methods include long-term contact lens use, instillations of autologous serum (eye drops, injections of botulinum toxin (induces ptosis, antiviral agent use or oral intake of metalloproteinase inhibitors. Cell membrane stabilizers, i.e., antioxidants, should be included into treatment approaches as well. Antioxidant effect of Emoxipine promotes tissue reparation due to the prevention of cell membrane lipid peroxidation as well as due to its anti-hypoxic, angioprotective, and antiplatelet effects. If conservative therapy

  18. CORNEAL HAZE FOLLOWING PHOTO REFRACT IVE KERATECTOMY

    OpenAIRE

    Atul; Superna; Pervaiz

    2015-01-01

    To assess the incidence of corneal haze following surface ablation in (PRK) in high myopic patients (≥6D). METHODS: In this prospective clinical study , 25 patients with high myopia (≥6D) that is 50 eyes in total , underwent photorefractive keratectomy by Schwind Amaris 500E laser machine. At the initial presentation , each patient underwent a detailed clinical evaluation that included recording of medical history , detailed ocular history , ...

  19. Avaliação da qualidade de corte do microceratótomo Masyk® na confecção de lamela corneana pediculada em olhos porcinos Evaluation of the cut quality of the Masyk® microkeratome in obtaining corneal flap from porcine eyes

    Directory of Open Access Journals (Sweden)

    Gustavo Victor

    2006-02-01

    Full Text Available OBJETIVO: Avaliar a qualidade de corte do microceratótomo Masyk® na confecção de lamela corneana pediculada em olhos porcinos. MÉTODOS: Realizou-se estudo prospectivo na Eye Clinic Day Hospital (São Paulo, Brasil em 31 olhos porcinos divididos em 2 grupos: 15 olhos nos quais se utilizou a plataforma de 160 µm e anel de sucção de 9,5 mm de diâmetro (Grupo 1 e 16 olhos, submetidos à plataforma de 140 µm e anel de sucção de 8,5 mm de diâmetro (Grupo 2. As espessuras efetivas das lamelas foram aferidas pelo paquímetro P55 (Paradigm, EUA e os diâmetros verticais do leito estromal com compasso cirúrgico. RESULTADOS: Não ocorreram complicações durante a utilização do microceratótomo e não foram identificadas lamelas livres, perfuradas ou incompletas. No grupo 1, a média das espessuras efetiva foi de 146,33 ± 15,43 µm, com variação entre 127 e 186 µm. A média das medidas do diâmetro vertical do leito residual foi de 9,39 ± 0,26 mm, com variação entre 8,90 e 9,85 mm. No grupo 2, a média das espessuras efetiva foi de 128,75 ± 18,83 µm, com variação entre 71 e 178 µm. A média das medidas do diâmetro do leito residual foi de 8,27 ± 0,20 mm, com variação entre 7,95 e 8,65 mm. CONCLUSÃO: O microceratótomo Masyk® mostrou-se eficaz e seguro em confeccionar lamelas corneanas pediculadas de espessura e diâmetros adequados em olhos porcinos.PURPOSE: Evaluation of the cut quality of the Masyk® microkeratome in obtaining corneal flap from porcine eyes. METHODS: Prospective study with 31 porcine eyes divided into two groups: 15 eyes with programmed flap thickness of 160 µm and 9.5 mm diameter (Group 1, and 16 eyes with programmed flap thickness of 140 µm and 8.5 mm diameter (Group 2. Corneal thickness was calculated with a P55 pachymeter (Paradigm, USA and the diameter with compass. RESULTS: No complications were observed during the use of the microkeratome. In group 1, the central corneal thickness mean was 146

  20. Corneal topography of excimer laser photorefractive keratectomy.

    Science.gov (United States)

    Klyce, S D; Smolek, M K

    1993-01-01

    The application of the 193 nm excimer laser for keratorefractive surgery promises to deliver a higher degree of precision and predictability than traditional procedures such as radial keratotomy. The development and evaluation of keratorefractive surgery have benefited from the parallel advances made in the field of corneal topography analysis. We used the Computed Anatomy Topography Modeling System (TMS-1) to analyze a Louisiana State University (LSU) Eye Center series of patients who had photorefractive keratectomy for the treatment of myopia with the VISX Twenty/Twenty excimer laser system. The excimer ablations were characterized by a relatively uniform distribution of surface powers within the treated zone. In the few cases that exhibited marked refractive regression, corneal topography analysis showed correlative changes. With topographical analysis, centration of the ablations relative to the center of the pupil could be evaluated. Marked improvement in centration occurred in the patients of LSU Series IIB in which the procedure to locate the point on the cornea directly over the pupil's center during surgery was refined. Corneal topographical analysis provides objective measures of keratorefractive surgical results and is able to measure the precise tissue removal effect of excimer laser ablation without the uncertainties caused by measuring visual acuity alone. Our observations forecast the need for improved aids to center the laser ablations and for the development of a course of treatment to prevent post-ablation stromal remodeling. PMID:8450433

  1. Correlation between Corneal Endothelial Cell Loss and Location of Phacoemulsification Incision

    Directory of Open Access Journals (Sweden)

    Hamid Gharaee

    2011-01-01

    Full Text Available Purpose: To assess the relationship between corneal endothelial cell loss after phacoemulsification and the location of the clear corneal incision. Methods: A total of 92 patients (92 eyes with senile cataracts who met the study criteria were included in this cross sectional study and underwent phacoemulsification. The incision site was determined based on the steep corneal meridian according to preoperative keratometry. Endothelial cell density was measured using specular microscopy in the center and 3 mm from the center of the cornea in the meridian of the incisions (temporal, superior, and superotemporal. Phacoemulsification was performed by a single surgeon using the phaco chop technique through a 3.2 mm clear cornea incision. Endothelial cell loss (ECL was evaluated 1 week, and 1 and 3 months postoperatively. Results: At all time points during follow-up, ECL was comparable among the 3 incision sites, both in the central cornea and in the meridian of the incision (P > 0.05 for all comparisons. However, 3 months postoperatively, mean central ECL with superior incisions and mean sectoral ECL with temporal incisions were slightly higher. Superotemporal incisions entailed slightly less ECL than the other 2 groups. Overall, one month after surgery, mean central ECL was 10.8% and mean ECL in the sector of the incisions was 14.0%. Axial length and effective phaco time (EFT were independent predictors of postoperative central ECL (P values 0.005 and < 0.0001, respectively. Conclusion: A superotemporal phacoemulsification incision may entail less ECL as compared to other incisions (although not significantly different. The amount of central ECL may be less marked in patients with longer axial lengths and with procedures utilizing less EFT.

  2. Putative epidermal stem cell convert into corneal epithelium-like cell under corneal tissue in vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Rhesus putative epidermal stem cells are being investigated for their potential use in regenerative corneal epithelium-like cells, which may provide a practical source of autologous seed cells for the construction of bioengineered corneas. The goal of this study was to investigate the potential of epi-dermal stem cells for trans-differentiation into corneal epithelium-like cells. Rhesus putative epidermal stem cells were isolated by type IV collagen attachment method. Flow cytometry analysis, immuno-histology and RT-PCR were conducted to identify the expression of specific markers (β1, α6 integrin, K15, K1/K10, K3/K12 and CD71) on the isolated rapid attaching cells. The isolated cells were cocultured with human corneal limbal stroma and corneal epithelial cells. After coculture, the expression of the same specific markers was evaluated in order to identify expression difference caused by the coculture conditions. K3/K12 expression was analyzed in coculture cells on day 2, 4, 6, 8 and 10. Putative epi-dermal stem cells in conditioned culture media were used as control. Putative epidermal stem cells were predominant in rapid attaching cells by type IV collagen attachment isolation. Before being co-cultured, the rhesus putative epidermal stem cells expressed K15, α6 and β1 integrin, but no CD71, K1/K10 and K3/K12. After coculture, these cells expressed K3/K12 (a marker of corneal epithelial cells), K15 and β 1 integrin, but no K1/K10. Cells being not coculture converted into terminally differentiated cells expressing K1/K10. These results indicate that rhesus putative epidermal stem cells can trans-differentiate into corneal epithelium-like cells and, therefore, may have potential therapeutic application as autologous seed cells for the construction of bioengineered corneas.

  3. 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.

  4. Combining femtosecond laser ablation and diode laser welding in lamellar and endothelial corneal transplants

    Science.gov (United States)

    Pini, Roberto; Rossi, Francesca; Matteini, Paolo; Ratto, Fulvio; Menabuoni, Luca; Lenzetti, Ivo; Yoo, Sonia H.; Parel, Jean-Marie

    2008-02-01

    Based on our previous clinical experiences in minimally invasive diode laser-induced welding of corneal tissue in penetrating keratoplasty (PK), i.e. full-thickness transplant of the cornea, we combined this technique with the use of a femtosecond laser for applications in lamellar (LK) and endothelial (EK) keratoplasty. In LK, the femtosecond laser was used to prepare donor button and recipient corneal bed; the wound edges were stained with a water solution of Indocyanine Green (ICG) and then irradiated with a diode laser emitting in CW mode to induce stromal welding. Intraoperatory observations and follow-up results up to 6 months indicated the formation of a smooth stromal interface, total absence of edema as well as inflammation, and reduction of post-operative astigmatism, as compared with conventional suturing procedures. In EK the femtosecond laser was used for the preparation of a 100 μm thick, 8.5mm diameter donor corneal endothelium flap. The flap stromal side was stained with ICG. After stripping the recipient Descemet's membrane and endothelium, the donor flap was positioned in the anterior chamber on the inner face of the cornea by an air bubble and secured to the recipient cornea by diode laser pulses delivered by means of a fiberoptic contact probe introduced in the anterior chamber, which produced welding spots of 200 μm diameter. Femtosecond laser sculpturing of the donor cornea provided lamellar and endothelial flaps of preset and constant thickness. Diode laserinduced welding showed a unique potential to permanently secure the donor flap in place, avoiding postoperative displacement and inflammation reaction.

  5. Changes in thickness of each layer of developing chicken cornea after administration of caffeine.

    Directory of Open Access Journals (Sweden)

    Hieronim Bartel

    2010-08-01

    Full Text Available The aim of the study was the presentation of changes in thickness of each layer of a developing cornea, that came into being under an influence of caffeine which was administered to chicken embryos. Research materials were 26 chicken embryos from breeding eggs that had been incubated. Breeding eggs were divided into two groups: control (n=30 in which Ringer liquid was given, and experimental (n=30 in which teratogenic dose of caffeine was administrated - 3.5 mg/egg. In 36th hour of incubation solutions were given with cannula through a hole in an egg shell directly onto amniotic membrane. After closing the hole with paraffin, eggs were put back into incubator. On 10th and 19th day of incubation corneas were taken for morphometric and morphological analysis. In experimental groups reduction of corneal thickness, thickening of corneal epithelium and corneal endothelium as well as Bowman's and Descemet's membranes, decrease of thickness of corneal stroma in comparison with the control group have been observed. Caffeine causes thickness changes of all layers and decreases the total thickness of a developing cornea.

  6. Hipertensão ocular "mascarada" por edema de córnea após cirurgia da catarata Ocular hipertension confounded by corneal edema after cataract surgery

    Directory of Open Access Journals (Sweden)

    Bruno de Freitas Valbon

    2009-12-01

    intraocular pressure (IOP measurements in cases with thick and flatter corneas. This is thought to occur linearly based on mathematical and on experimental studies. However, such influence does exist, but this is more complex than the one anticipated by pachymetry and keratometry because it is related to corneal biomechanical properties. The ocular response analyzer (ORA Reichert provides the data related to the biomechanical properties of the cornea along with the IOP measurements that are calibrated for correlating to the Goldmann applanation and also compensated from corneal properties. Also corneal tomography with a pachymetric map evaluation characterizes the cornea beyond central thickness and anterior curvature. In this article, we report a case of a 77 years old female patient with low vision, photofobia and ocular pain 28 days after phacoemulsification and intraocular lens implant. In the first visit, GAT was 14mmHg, while IOPcc (ORA corneal compensated IOP was 25,6mmHg. Corneal hysteresis and resistance factor were low: 4,1 and 6,1mmHg respectively despite a central thickness of 601 micron. Corneal thickness spatial profile was attenuated with an edematous pattern that was also observed by the Scheimpflug images (Pentacam. Hypertensive uveitis was diagnosed and the patient was started on a fixed combination of timolol and brimonidine associate with prednisolone acetate. Three weeks after, the patient referred resolution of photofobia and marked improvement of vision. Clinically, edema was resolved as observed by corneal tomographyc and biomechanical findings.

  7. Representational Thickness

    DEFF Research Database (Denmark)

    Mullins, Michael

    be implemented to improve design conditions for architects, thereby increasing the “thickness of representation”. The study commences from a broader theoretical enquiry, a review of previous research and examples of relevant context in which virtual reality has been used in practice. It develops from......Contemporary communicational and informational processes contribute to the shaping of our physical environment by having a powerful influence on the process of design. Applications of virtual reality (VR) are transforming the way architecture is conceived and produced by introducing dynamic...... elements into the process of design. Through its immersive properties, virtual reality allows access to a spatial experience of a computer model very different to both screen based simulations as well as traditional forms of architectural representation. The dissertation focuses on processes of the current...

  8. Can opposite clear corneal incisions have a role with post-laser in situ keratomileusis astigmatism?

    OpenAIRE

    Hatem El-Awady; Asaad A Ghanem

    2012-01-01

    Purpose: To evaluate the astigmatic correcting effect of paired opposite clear corneal incisions (OCCIs) on the steep axis in patients with residual astigmatism after laser in situ keratomileusis (LASIK) Materials and Methods: Thirty-one eyes of 24 patients with a mean age of 28.4 years ±2.46 (range, 19-36 years) were recruited for the study. Inclusion criteria included residual astigmatism of ≥1.5 diopter (D) after LASIK with inadequate residual stromal bed thickness that precluded ablat...

  9. Comparison of corneal sensitivity, tear function and corneal staining following laser in situ keratomileusis with two femtosecond laser platforms

    Directory of Open Access Journals (Sweden)

    Petznick A

    2013-03-01

    Full Text Available Andrea Petznick,1 Annabel Chew,2 Reece C Hall,2 Cordelia ML Chan,2 Mohamad Rosman,1,2 Donald Tan,1–3 Louis Tong,1–4 Jodhbir S Mehta1–31Singapore Eye Research Institute, Singapore; 2Singapore National Eye Centre, Singapore; 3Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; 4Duke-NUS Graduate Medical School, SingaporePurpose: To evaluate longitudinal changes in corneal sensitivity, tear function, and corneal staining in patients who underwent laser in situ keratomileusis (LASIK using two different femtosecond lasers.Methods: In a prospective, randomized clinical trial, contralateral eyes of 45 patients underwent flap creation by either VisuMax or IntraLase™ femtosecond laser. Corneal sensitivity, tear break up time (TBUT, Schirmer’s test, and corneal fluorescein staining were assessed preoperatively and at 1 week, 1 month, and 3 months postoperatively.Results: There were no statistical differences in any clinical outcome measure between the two femtosecond lasers (P > 0.05, although there was a trend towards slightly lower reductions for corneal sensitivity and TBUT in VisuMax-operated eyes. Overall, corneal sensitivity was significantly reduced at 1 week (P 0.05.Conclusion: This study showed that changes in corneal sensitivity, tear function, and corneal staining were statistically similar in LASIK using VisuMax and IntraLase femtosecond lasers for flap creation. However, the trend towards faster recovery of corneal sensitivity and TBUT observed in VisuMax-operated eyes may be attributable to improved technical specifications.Keywords: femtosecond laser, corneal sensitivity, tear film break-up time, Schirmer’s, corneal staining

  10. Corneal stem cells and tissue engineering: Current advancesand future perspectives

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Major advances are currently being made in regenerativemedicine for cornea. Stem cell-based therapiesrepresent a novel strategy that may substituteconventional corneal transplantation, albeit there aremany challenges ahead given the singularities of eachcellular layer of the cornea. This review recapitulatesthe current data on corneal epithelial stem cells,corneal stromal stem cells and corneal endothelialcell progenitors. Corneal limbal autografts containingepithelial stem cells have been transplanted in humansfor more than 20 years with great successful rates,and researchers now focus on ex vivo cultures andother cell lineages to transplant to the ocular surface.A small population of cells in the corneal endotheliumwas recently reported to have self-renewal capacity,although they do not proliferate in vivo . Two mainobstacles have hindered endothelial cell transplantationto date culture protocols and cell delivery methods tothe posterior cornea in vivo . Human corneal stromalstem cells have been identified shortly after therecognition of precursors of endothelial cells. Stromalstem cells may have the potential to provide a directcell-based therapeutic approach when injected tocorneal scars. Furthermore, they exhibit the ability todeposit organized connective tissue in vitro and maybe useful in corneal stroma engineering in the future.Recent advances and future perspectives in the field arediscussed.

  11. Changes of Corneal Optical Properties after UVB Irradiation Investigated Spectrophotometrically

    Czech Academy of Sciences Publication Activity Database

    Čejka, Čestmír; Pláteník, J.; Širc, Jakub; Ardan, Taras; Michálek, Jiří; Brůnová, B.; Čejková, Jitka

    2010-01-01

    Roč. 59, č. 4 (2010), s. 591-597. ISSN 0862-8408 Grant ostatní: GA MŠk(CZ) 1M0538 Institutional research plan: CEZ:AV0Z50390512; CEZ:AV0Z40500505 Keywords : corneal hydration * corneal light absorption * absorption coefficients Subject RIV: FF - HEENT, Dentistry Impact factor: 1.646, year: 2010

  12. Developmental Corneal Innervation: Interactions between Nerves and Specialized Apical Corneal Epithelial Cells

    OpenAIRE

    Kubilus, James K.; Linsenmayer, Thomas F.

    2010-01-01

    During developmental innervation of the chicken cornea, nerves interact with apical corneal epithelial cells to form synapse-like structures. In addition, these apical epithelial cells express class III β-tubulin, an isoform of β-tubulin generally thought to be neuron specific.

  13. Customized toric intraocular lens implantation for correction of extreme corneal astigmatism due to corneal scarring

    Directory of Open Access Journals (Sweden)

    R Bassily

    2010-03-01

    Full Text Available R Bassily, J LuckOphthalmology Department, Royal United Hospital, Combe Park, Bath, UKAbstract: A 76-year-old woman presented with decreased visual function due to cataract formation. Twenty-five years prior she developed right sided corneal ulceration that left her with 10.8 diopters (D of irregular astigmatism at 71.8° (steep axis. Her uncorrected visual acuity was 6/24 and could only ever wear a balanced lens due to the high cylindrical error. Cataract surgery was planned with a custom designed toric intraocular lens (IOL with +16.0 D sphere inserted via a wound at the steep axis of corneal astigmatism. Postoperative refraction was -0.75/+1.50 × 177° with a visual acuity of 6/9 that has remained unchanged at six-week follow-up with no IOL rotation. This case demonstrates the value of high power toric IOLs for the correction of pathological corneal astigmatism.Keywords: intraocular lens, corneal ulceration, visual acuity, scarring

  14. Paracentral Corneal Dellen:A Rare Sign of Graves Ophthalmopathy

    Institute of Scientific and Technical Information of China (English)

    Jianhua Yan; Zhongyao Wu

    2003-01-01

    Purpose: To report a rare sign, paracentral corneal dellen that developed in a middleaged female patient with Graves ophthalmopathy.Methods:A paracentral corneal dellen developed in the left eye in a 42-year-old woman who was diagnosed as Graves ophthalmopathy. The patient had remarkable upper eyelid retraction, upper eyelid lag and upward motility restriction. The Graves ophthalmopathy was classified as Grade V according to NOSPECS classification.Results:Local artificial tear film and 0.3% Tobramycin eye drops were administered to both eyes.Twenty-four hours later, the left corneal dellen disappeared.Conclusions:Graves ophthalmopathy can lead to paracentral corneal dellen because of severe upper eyelid retraction and upward motility restriction of the eye in spite of the lack of lagophthalmos. Artificial tear drop and antibiotic eye drop therapy helped even though the patient did not have corneal exposure.

  15. Contact Lens-Related Corneal Infections - United States, 2005-2015.

    Science.gov (United States)

    Cope, Jennifer R; Collier, Sarah A; Srinivasan, Krithika; Abliz, Erkinay; Myers, Ann; Millin, Courtney J; Miller, Andrew; Tarver, Michelle E

    2016-01-01

    Keratitis (inflammation of the cornea) can result from contact lens wear or other causes. Keratitis from all causes, including contact lens wear, results in approximately 1 million clinic and emergency department visits annually, with an estimated cost of $175 million in direct health care expenditures in 2010 (1). Approximately 41 million U.S. residents wear contact lenses, and in 2014, >99% of contact lens wearers surveyed reported at least one behavior that puts them at risk for a contact lens-related eye infection (2). The Center for Devices and Radiological Health at the Food and Drug Administration (FDA) regulates contact lenses as medical devices, and certain adverse events related to contact lenses are reported to FDA's Medical Device Report (MDR) database. To describe contact lens-related corneal infections reported to the FDA, 1,075 contact lens-related MDRs containing the terms "ulcer" or "keratitis" reported to FDA during 2005-2015 were analyzed. Among these 1,075 reports, 925 (86.0%) were reported by a contact lens manufacturer and 150 (14.0%) by an eye care provider or patient. Overall, 213 (19.8%) reports described a patient who had a central corneal scar, had a decrease in visual acuity, or required a corneal transplant following the event. Among the reports, 270 (25.1%) described modifiable factors known to be associated with an increased risk for contact lens-related corneal infections, including sleeping in contact lenses or poor contact lens hygiene; the remainder did not provide details that permitted determination of associated factors. Continued efforts to educate contact lens wearers about prevention of contact lens-related eye infections are needed. PMID:27538244

  16. Riboflavin concentration in corneal stroma after intracameral injection

    Institute of Scientific and Technical Information of China (English)

    Na; Li; Xiu-Jun; Peng; Zheng-Jun; Fan; Xu; Pang; Yu; Xia; Teng-Fei; Wu

    2015-01-01

    AIM: To evaluate the enrichment of riboflavin in the corneal stroma after intracameral injection to research the barrier ability of the corneal endothelium to riboflavin in vivo.METHODS: The right eyes of 30 New Zealand white rabbits were divided into three groups. Different concentrations riboflavin-balanced salt solutions(BSS)were injected into the anterior chamber(10 with 0.5%, 10 with 1%, and 10 with 2%). Eight corneal buttons of 8.5mm in diameter from each group were dissected at 30 min after injection and the riboflavin concentrations in the corneal stroma were determined using high-performance liquid chromatography(HPLC) after removing the epithelium and endothelium. The other two rabbits in every group were observed for 24 h and sacrificed. As a comparison, the riboflavin concentrations from 16 corneal stromal samples were determined using HPLC after instillation of 0.1% riboflavin-BSS solution for30 min on the corneal surface(8 without epithelium and 8with intact epithelium).RESULTS: The mean riboflavin concentrations were11.19, 18.97, 25.08, 20.18, and 1.13 μg/g for 0.5%, 1%, 2%,de-epithelialzed samples, and the transepithelial groups,respectively. The color change of the corneal stroma and the HPLC results showed that enrichment with riboflavin similar to classical de-epithelialized corneal collagen crosslinking(CXL) could be achieved by intracameral 1%riboflavin-BSS solution after 30min; the effect appeared to be continuous for at least 30 min.CONCLUSION: Riboflavin can effectively penetrate the corneal stroma through the endothelium after an intracameral injection in vivo, so it could be an enhancing method that could improve the corneal riboflavin concentration in transepithelial CXL.

  17. In Vivo Confocal Microscopic Observation of Lamellar Corneal Transplantation in the Rabbit Using Xenogenic Acellular Corneal Scaffolds as a Substitute

    Institute of Scientific and Technical Information of China (English)

    Yun Feng; Wei Wang

    2015-01-01

    Background:The limiting factor to corneal transplantation is the availability of donors.Research has suggested that xenogenic acellular corneal scaffolds (XACS) may be a possible alternative to transplantation.This study aimed to investigate the viability of performing lamellar corneal transplantation (LCT) in rabbits using canine XACS.Methods:Fresh dog corneas were decellularized by serial digestion,and LCT was performed on rabbit eyes using xenogeneic decellularized corneal matrix.Cellular and morphological changes were observed by slit-lamp,light,and scanning electron microscopy at 7,30 and 90 days postoperatively.Immunocytochemical staining for specific markers such as keratin 3,vimentin and MUC5AC,was used to identify cells in the graft.Results:Decellularized xenogenic corneal matrix remained transparent for about 1-month after LCT.The recipient cells were able to survive and proliferate into the grafts.Three months after transplantation,grafts had merged with host tissue,and graft epithelialization and vascularization had occurred.Corneal nerve fibers were able to grow into the graft in rabbits transplanted with XACS.Conclusions:Xenogenic acellular corneal scaffolds can maintain the transparency of corneal grafts about 1-month and permit growth of cells and nerve fibers,and is,therefore,a potential substitute or carrier for a replacement cornea.

  18. Mycotic corneal ulcers in upper Assam

    Directory of Open Access Journals (Sweden)

    Reema Nath

    2011-01-01

    Full Text Available Purpose : To study the association of various risk factors and epidemiological variables of mycotic keratitis treated at a tertiary referral hospital of upper Assam. Materials and Methods: In this hospital-based prospective study a total of 310 consecutive corneal ulcer cases attending the ophthalmology outpatient department of Assam Medical College were enrolled between April 2007 and March 2009. After clinical and slit-lamp biomicroscopic examination in all suspected cases, smears and culture examination for fungus was done to establish the etiology. Demographic information and associated probable risk factors of individual cases were noted in a predesigned questionnaire. Results: In 188 (60.6% cases fungal etiology could be established. Out of them 67.6% were males. The most commonly affected age group was 41-50 years (25.5%. The maximum (23.4% cases were reported during the paddy harvesting season in Assam (January and February. Fungal element could be demonstrated in 65.2% cases in direct potassium hydroxide (KOH mount. The commonest predisposing factor was corneal injury (74.5%. While diabetes was a significant systemic predisposing factor in mixed bacterial and fungal infections in 11.1% cases, blocked naso-lacrimal duct was the local predisposing factor in 11.1% of cases. Fusarium solani (25% was the commonest isolate followed by Aspergillus species (19%, Curvularia species (18.5% and Penicillium species (15.2%. Yeasts were isolated in 2.7% (n=5 cases. Conclusions : Ocular trauma was the commonest cause of fungal corneal ulcer in Assam and Fusarium solani was the commonest species responsible for it. Most of the mycotic ulcer cases come from rural areas including the tea gardens.

  19. Fractal dimension based corneal fungal infection diagnosis

    Science.gov (United States)

    Balasubramanian, Madhusudhanan; Perkins, A. Louise; Beuerman, Roger W.; Iyengar, S. Sitharama

    2006-08-01

    We present a fractal measure based pattern classification algorithm for automatic feature extraction and identification of fungus associated with an infection of the cornea of the eye. A white-light confocal microscope image of suspected fungus exhibited locally linear and branching structures. The pixel intensity variation across the width of a fungal element was gaussian. Linear features were extracted using a set of 2D directional matched gaussian-filters. Portions of fungus profiles that were not in the same focal plane appeared relatively blurred. We use gaussian filters of standard deviation slightly larger than the width of a fungus to reduce discontinuities. Cell nuclei of cornea and nerves also exhibited locally linear structure. Cell nuclei were excluded by their relatively shorter lengths. Nerves in the cornea exhibited less branching compared with the fungus. Fractal dimensions of the locally linear features were computed using a box-counting method. A set of corneal images with fungal infection was used to generate class-conditional fractal measure distributions of fungus and nerves. The a priori class-conditional densities were built using an adaptive-mixtures method to reflect the true nature of the feature distributions and improve the classification accuracy. A maximum-likelihood classifier was used to classify the linear features extracted from test corneal images as 'normal' or 'with fungal infiltrates', using the a priori fractal measure distributions. We demonstrate the algorithm on the corneal images with culture-positive fungal infiltrates. The algorithm is fully automatic and will help diagnose fungal keratitis by generating a diagnostic mask of locations of the fungal infiltrates.

  20. Adjuvant corneal crosslinking to prevent hyperopic LASIK regression

    Directory of Open Access Journals (Sweden)

    Aslanides IM

    2013-03-01

    Full Text Available Ioannis M Aslanides, Achyut N MukherjeeEmmetropia Mediterranean Eye Clinic, Heraklion, Crete, GreecePurpose: To report the long term outcomes, safety, stability, and efficacy in a pilot series of simultaneous hyperopic laser assisted in situ keratomileusis (LASIK and corneal crosslinking (CXL.Method: A small cohort series of five eyes, with clinically suboptimal topography and/or thickness, underwent LASIK surgery with immediate riboflavin application under the flap, followed by UV light irradiation. Postoperative assessment was performed at 1, 3, 6, and 12 months, with late follow up at 4 years, and results were compared with a matched cohort that received LASIK only.Results: The average age of the LASIK-CXL group was 39 years (26–46, and the average spherical equivalent hyperopic refractive error was +3.45 diopters (standard deviation 0.76; range 2.5 to 4.5. All eyes maintained refractive stability over the 4 years. There were no complications related to CXL, and topographic and clinical outcomes were as expected for standard LASIK.Conclusion: This limited series suggests that simultaneous LASIK and CXL for hyperopia is safe. Outcomes of the small cohort suggest that this technique may be promising for ameliorating hyperopic regression, presumed to be biomechanical in origin, and may also address ectasia risk.Keyword: CXL

  1. Corneal surface reconstruction - a short review

    Directory of Open Access Journals (Sweden)

    Madhavan H N

    2009-01-01

    Full Text Available Cornea is the clear, dome-shaped surface that covers the front of the eye and when damage due to burns or injury and several other diseases, stem cells residing in its rim called "limbus" are stimulated to multiply to support growth of new epithelial cells over its surface. If this ready source of stem cells is damaged or destroyed the natural repair is not possible and such a condition is known as corneal limbal stem cell deficiency (CLSCD disease. Stem cell transplant helps such persons to regenerate the corneal surface. Human corneal limbal stem cell transplantation is at present an established procedure with reasonable good clinical outcome particularly when autologous limbal epithelial tissue from a fellow unaffected eye is used. 1, 2 A major concern related to the autograft is the possibility of CLSCD at the donor site, 3 techniques that allowed the expansion of a small limbal biopsy in the laboratory using cell cultures that could be then transplanted to the affected eye have been developed ,4, 5 Human amniotic membrane (HAM is used as a scaffold for both culturing the human limbal epithelial cells and for ocular surface reconstruction with the cultured limbal epithelial cells. 4-7 However, researchers have used alternative scaffolds like collagen 8, fibrin gel 9 and cross-linked gel of fibronectin and fibrin. 10 All these are biological materials and also need for animal 3T3 feeder layer for stem cell cultures. The properties of HAM are unique including antiadhesive effects, bacteriostatic effects, wound protection, pain reduction, and improvement of epithelialization and characteristically lacking imunogenicity. The use of amniotic membrane transplantation (AMT to treat ocular surface abnormalities was first reported by Graziella Pellegrini, chief of stem cell laboratory at Giovanni Paolo Hospital in Venice, Italy, who was the first to demonstrate the limbal stem cell transplant in 1997. Amniotic membrane has been successfully used in

  2. Corneal surface reconstruction - a short review

    OpenAIRE

    Madhavan H N

    2009-01-01

    Cornea is the clear, dome-shaped surface that covers the front of the eye and when damage due to burns or injury and several other diseases, stem cells residing in its rim called "limbus" are stimulated to multiply to support growth of new epithelial cells over its surface. If this ready source of stem cells is damaged or destroyed the natural repair is not possible and such a condition is known as corneal limbal stem cell deficiency (CLSCD) disease. Stem cell transplant helps such persons to...

  3. Comparison of corneal histopathology changes between the rigid gas permeable contact lens wearers and the soft contact lens wearers%配戴RGPCL和SCL后角膜组织病理学变化的比较

    Institute of Scientific and Technical Information of China (English)

    韩治华; 胡楠

    2010-01-01

    in the SCL group than in the RGPCL group (F=4.262, P<0.05), and corneal vesicles and corneal gutata were occasionally observed. The density of the Langerhans cells both in the central and peripheral cornea was higher in the SCL group (F=5.362, P<0.05;F=-14.910, P<0.05), and the tortuosity of the nerve fibers increased significantly in the eyes of those wearing SCL compared with those wearing RGPCL. The density of the anterior stromal cells was lower (P<0.05) while the microdot densities in the stroma were higher in the SCL group than in the RGPCL group (P<0.05). The polymorphology of the corneal endothelial cells was more apparent in the SCL group, but the density of the endothelial cells was similar for the 2 groups. The thickness of the central corneal epithelium was thinner for SCL wearers compared to RGPCL wearers (F=-2.061, P<0.05). There were no differences for all of the indices within the same group at 3 months, 6 months and 12 months. Conclusion The corneal morphologic changes of RGPCL wearers are less severe than those of SCL wearers, suggesting that RGPCL wearing is a safe correction method.

  4. [The irido-corneo-endothelial syndrome. The loss of the control of corneal endothelial cell cycle. A review].

    Science.gov (United States)

    Robert, A M; Renard, G; Robert, L; Bourges, J-L

    2013-04-01

    The three major symptoms of the irido-corneo-endothelial syndrome are the alterations of the corneal endothelium and of the iris with a loss of the regulation of the cell cycle, and the progressive obstruction of the irido-corneal angle. This rare pathology attacks mainly young adult women. Most of the symptoms and complications originate from the excessive proliferation of the corneal endothelial cells accompanied by the evolution of their phenotype towards that of the epithelial cells. In normal conditions the corneal endothelial cells do not divide, they are blocked in the G1 stage of the cell cycle, mainly because of the action of the inhibitors of cyclin-dependent kinases. Still these cells retain a good capacity for proliferation, which can be induced by the down-regulation of the expression of the inhibitors of the cyclin-dependent kinases. This proliferative capacity declines with age and is also different according to the localization of the cells: it is more intense with those originating from the central area then in those from the peripheral area of the cornea. The age-related decline of the proliferative capacity is not due to the shortening of the telomers, but to the stress-induced accelerated senescence of the cells. PMID:23123109

  5. Temporary graft for closed-system cataract surgery during corneal triple procedures.

    Science.gov (United States)

    Nardi, M; Giudice, V; Marabotti, A; Alfieri, E; Rizzo, S

    2001-08-01

    Performing phacoemulsification during a triple corneal procedure has many advantages. Operating in a closed chamber makes surgery easier and safer. In some cases, however, a dense corneal opacity may prevent closed-chamber surgery, necessitating the use of an open-sky technique. In these cases, a temporary corneal graft using a corneal button not suitable for penetrating keratoplasty is proposed to allow phacoemulsification and foldable intraocular lens implantation through a corneal tunnel. The temporary corneal graft is replaced with a permanent graft after these steps are completed. This technique was effective in 3 patients with cataract and dense corneal opacity. PMID:11524186

  6. Posterior Corneal Curvature Assessment after Epi-LASIK for Myopia: Comparison of Orbscan II and Pentacam Imaging

    OpenAIRE

    Byun, Yong-Soo; Chung, So-Hyang; Park, Young-Geun; Joo, Choun-Ki

    2012-01-01

    Purpose To compare the changes in posterior corneal curvature using scanning slit topography (Orbscan II) and Scheimpflug imaging (Pentacam) before and after Epi-laser in situ keratomileusis (LASIK) for myopia. Methods In a prospective observational case-series study, 20 myopic patients having undergone Epi-LASIK were examined serially with two different devices, Orbscan II and Pentacam, preoperatively and one month postoperatively. Posterior central elevation (PCE) and posterior maximal elev...

  7. Corneal topography, refractive state, and accommodation in harbor seals (Phoca vitulina).

    Science.gov (United States)

    Hanke, Frederike D; Dehnhardt, Guido; Schaeffel, Frank; Hanke, Wolf

    2006-03-01

    Corneal topography of a harbor seal measured with a Placido's disc shows a central flattened stripe in the vertical meridian. Together with a pupil that can form a vertical slit, the flat vertical meridian can minimize the optical effects caused by the transition from water to air. Using infrared (IR) photoretinoscopy, we analyzed the refractive state of harbor seals and revealed a high degree of myopia and astigmatism in air, but emmetropia or slight hyperopia with little astigmatism underwater. The brightness distribution in the pupils suggest the presence of a multifocal dioptric apparatus in air and underwater. We found a first indication for accommodation by dynamic recordings underwater. PMID:16256164

  8. Corneal astigmatism measuring module for slit lamps

    International Nuclear Information System (INIS)

    We have developed an automatic keratometer module for slit lamps that provides automatic measurements of the radii of the corneal curvature. The system projects 72 light spots displayed in a precise circle at the examined cornea. The displacement and deformation of the reflected image of these light spots are analysed providing the keratometry. Measurements in the range of 26.8-75 D can be obtained and a self-calibration system has been specially designed in order to keep the system calibrated. Infrared LEDs indicate automatically which eye is being examined. Volunteer patients (492) have been submitted to the system and the results show that our system has a high correlation factor with the commercially available manual keratometers and the keratometry measurements from a topographer. Our developed system is 95% in agreement with the corneal topographer (Humphrey-Atlas 995 CZM) and the manual keratometer (Topcon OM-4). The system's nominal precision is 0.05 mm for the radii of curvature and 10 for the associated axis

  9. Clinical utility of the KAMRA corneal inlay.

    Science.gov (United States)

    Naroo, Shehzad Anjam; Bilkhu, Paramdeep Singh

    2016-01-01

    The treatment of presbyopia has been the focus of much scientific and clinical research over recent years, not least due to an increasingly aging population but also the desire for spectacle independence. Many lens and nonlens-based approaches have been investigated, and with advances in biomaterials and improved surgical methods, removable corneal inlays have been developed. One such development is the KAMRA™ inlay where a small entrance pupil is exploited to create a pinhole-type effect that increases the depth of focus and enables improvement in near visual acuity. Short- and long-term clinical studies have all reported significant improvement in near and intermediate vision compared to preoperative measures following monocular implantation (nondominant eye), with a large proportion of patients achieving Jaeger (J) 2 to J1 (~0.00 logMAR to ~0.10 logMAR) at the final follow-up. Although distance acuity is reduced slightly in the treated eye, binocular visual acuity and function remain very good (mean 0.10 logMAR or better). The safety of the inlay is well established and easily removable, and although some patients have developed corneal changes, these are clinically insignificant and the incidence appears to reduce markedly with advancements in KAMRA design, implantation technique, and femtosecond laser technology. This review aims to summarize the currently published peer-reviewed studies on the safety and efficacy of the KAMRA inlay and discusses the surgical and clinical outcomes with respect to the patient's visual function. PMID:27274194

  10. Clinical utility of the KAMRA corneal inlay

    Science.gov (United States)

    Naroo, Shehzad Anjam; Bilkhu, Paramdeep Singh

    2016-01-01

    The treatment of presbyopia has been the focus of much scientific and clinical research over recent years, not least due to an increasingly aging population but also the desire for spectacle independence. Many lens and nonlens-based approaches have been investigated, and with advances in biomaterials and improved surgical methods, removable corneal inlays have been developed. One such development is the KAMRA™ inlay where a small entrance pupil is exploited to create a pinhole-type effect that increases the depth of focus and enables improvement in near visual acuity. Short- and long-term clinical studies have all reported significant improvement in near and intermediate vision compared to preoperative measures following monocular implantation (nondominant eye), with a large proportion of patients achieving Jaeger (J) 2 to J1 (~0.00 logMAR to ~0.10 logMAR) at the final follow-up. Although distance acuity is reduced slightly in the treated eye, binocular visual acuity and function remain very good (mean 0.10 logMAR or better). The safety of the inlay is well established and easily removable, and although some patients have developed corneal changes, these are clinically insignificant and the incidence appears to reduce markedly with advancements in KAMRA design, implantation technique, and femtosecond laser technology. This review aims to summarize the currently published peer-reviewed studies on the safety and efficacy of the KAMRA inlay and discusses the surgical and clinical outcomes with respect to the patient’s visual function. PMID:27274194

  11. IOL Power Calculation after Corneal Refractive Surgery

    Directory of Open Access Journals (Sweden)

    Maddalena De Bernardo

    2014-01-01

    Full Text Available Purpose. To describe the different formulas that try to overcome the problem of calculating the intraocular lens (IOL power in patients that underwent corneal refractive surgery (CRS. Methods. A Pubmed literature search review of all published articles, on keyword associated with IOL power calculation and corneal refractive surgery, as well as the reference lists of retrieved articles, was performed. Results. A total of 33 peer reviewed articles dealing with methods that try to overcome the problem of calculating the IOL power in patients that underwent CRS were found. According to the information needed to try to overcome this problem, the methods were divided in two main categories: 18 methods were based on the knowledge of the patient clinical history and 15 methods that do not require such knowledge. The first group was further divided into five subgroups based on the parameters needed to make such calculation. Conclusion. In the light of our findings, to avoid postoperative nasty surprises, we suggest using only those methods that have shown good results in a large number of patients, possibly by averaging the results obtained with these methods.

  12. Growing Three-Dimensional Corneal Tissue in a Bioreactor

    Science.gov (United States)

    Spaulding, Glen F.; Goodwin, Thomas J.; Aten, Laurie; Prewett, Tacey; Fitzgerald, Wendy S.; OConnor, Kim; Caldwell, Delmar; Francis, Karen M.

    2003-01-01

    Spheroids of corneal tissue about 5 mm in diameter have been grown in a bioreactor from an in vitro culture of primary rabbit corneal cells to illustrate the production of optic cells from aggregates and tissue. In comparison with corneal tissues previously grown in vitro by other techniques, this tissue approximates intact corneal tissue more closely in both size and structure. This novel three-dimensional tissue can be used to model cell structures and functions in normal and abnormal corneas. Efforts continue to refine the present in vitro method into one for producing human corneal tissue to overcome the chronic shortage of donors for corneal transplants: The method would be used to prepare corneal tissues, either from in vitro cultures of a patient s own cells or from a well-defined culture from another human donor known to be healthy. As explained in several articles in prior issues of NASA Tech Briefs, generally cylindrical horizontal rotating bioreactors have been developed to provide nutrient-solution environments conducive to the 30 NASA Tech Briefs, October 2003 growth of delicate animal cells, with gentle, low-shear flow conditions that keep the cells in suspension without damaging them. The horizontal rotating bioreactor used in this method, denoted by the acronym "HARV," was described in "High-Aspect-Ratio Rotating Cell-Culture Vessel" (MSC-21662), NASA Tech Briefs, Vol. 16, No. 5 (May, 1992), page 150.

  13. Mutational spectrum of Korean patients with corneal dystrophy.

    Science.gov (United States)

    Chae, H; Kim, M; Kim, Y; Kim, J; Kwon, A; Choi, H; Park, J; Jang, W; Lee, Y S; Park, S H; Kim, M S

    2016-06-01

    Corneal dystrophy typically refers to a group of rare hereditary disorders with a heterogeneous genetic background. A comprehensive molecular genetic analysis was performed to characterize the genetic spectrum of corneal dystrophies in Korean patients. Patients with various corneal dystrophies underwent thorough ophthalmic examination, histopathologic examination, and Sanger sequencing. A total of 120 probands were included, with a mean age of 50 years (SD = 18 years) and 70% were female. A total of 26 mutations in five genes (14 clearly pathogenic and 12 likely pathogenic) were identified in 49 probands (41%). Epithelial-stromal TGFBI dystrophies, macular corneal dystrophy and Schnyder corneal dystrophy (SCD) showed 100% mutation detection rates, while endothelial corneal dystrophies showed lower detection rates of 3%. Twenty six non-duplicate mutations including eight novel mutations were identified and mutations associated with SCD were identified genetically for the first time in this population. This study provides a comprehensive characterization of the genetic aberrations in Korean patients and also highlights the diagnostic value of molecular genetic analysis in corneal dystrophies. PMID:26748743

  14. Impact of facial conformation on canine health: corneal ulceration.

    Directory of Open Access Journals (Sweden)

    Rowena M A Packer

    Full Text Available Concern has arisen in recent years that selection for extreme facial morphology in the domestic dog may be leading to an increased frequency of eye disorders. Corneal ulcers are a common and painful eye problem in domestic dogs that can lead to scarring and/or perforation of the cornea, potentially causing blindness. Exaggerated juvenile-like craniofacial conformations and wide eyes have been suspected as risk factors for corneal ulceration. This study aimed to quantify the relationship between corneal ulceration risk and conformational factors including relative eyelid aperture width, brachycephalic (short-muzzled skull shape, the presence of a nasal fold (wrinkle, and exposed eye-white. A 14 month cross-sectional study of dogs entering a large UK based small animal referral hospital for both corneal ulcers and unrelated disorders was carried out. Dogs were classed as affected if they were diagnosed with a corneal ulcer using fluorescein dye while at the hospital (whether referred for this disorder or not, or if a previous diagnosis of corneal ulcer(s was documented in the dogs' histories. Of 700 dogs recruited, measured and clinically examined, 31 were affected by corneal ulcers. Most cases were male (71%, small breed dogs (mean± SE weight: 11.4±1.1 kg, with the most commonly diagnosed breed being the Pug. Dogs with nasal folds were nearly five times more likely to be affected by corneal ulcers than those without, and brachycephalic dogs (craniofacial ratio <0.5 were twenty times more likely to be affected than non-brachycephalic dogs. A 10% increase in relative eyelid aperture width more than tripled the ulcer risk. Exposed eye-white was associated with a nearly three times increased risk. The results demonstrate that artificially selecting for these facial characteristics greatly heightens the risk of corneal ulcers, and such selection should thus be discouraged to improve canine welfare.

  15. Impact of facial conformation on canine health: corneal ulceration.

    Science.gov (United States)

    Packer, Rowena M A; Hendricks, Anke; Burn, Charlotte C

    2015-01-01

    Concern has arisen in recent years that selection for extreme facial morphology in the domestic dog may be leading to an increased frequency of eye disorders. Corneal ulcers are a common and painful eye problem in domestic dogs that can lead to scarring and/or perforation of the cornea, potentially causing blindness. Exaggerated juvenile-like craniofacial conformations and wide eyes have been suspected as risk factors for corneal ulceration. This study aimed to quantify the relationship between corneal ulceration risk and conformational factors including relative eyelid aperture width, brachycephalic (short-muzzled) skull shape, the presence of a nasal fold (wrinkle), and exposed eye-white. A 14 month cross-sectional study of dogs entering a large UK based small animal referral hospital for both corneal ulcers and unrelated disorders was carried out. Dogs were classed as affected if they were diagnosed with a corneal ulcer using fluorescein dye while at the hospital (whether referred for this disorder or not), or if a previous diagnosis of corneal ulcer(s) was documented in the dogs' histories. Of 700 dogs recruited, measured and clinically examined, 31 were affected by corneal ulcers. Most cases were male (71%), small breed dogs (mean± SE weight: 11.4±1.1 kg), with the most commonly diagnosed breed being the Pug. Dogs with nasal folds were nearly five times more likely to be affected by corneal ulcers than those without, and brachycephalic dogs (craniofacial ratio brachycephalic dogs. A 10% increase in relative eyelid aperture width more than tripled the ulcer risk. Exposed eye-white was associated with a nearly three times increased risk. The results demonstrate that artificially selecting for these facial characteristics greatly heightens the risk of corneal ulcers, and such selection should thus be discouraged to improve canine welfare. PMID:25969983

  16. Asphericity of the human cornea for different corneal diameters

    OpenAIRE

    González-Méijome, José Manuel; Villa-Collar, César; Montés-Micó, Robert; Gomes, Antonio

    2007-01-01

    PURPOSE: To measure the anterior corneal asphericity (Q) with different corneal diameters. SETTING: Department of Physics (Optometry), University of Minho, Braga, Portugal. METHODS: Thirty-six eyes of 36 patients were evaluated using a videokeratoscope, and the Q-values were recorded. Topographic data were also analyzed using Vol-CT 6.89 software (Sarver & Associates, Inc) to obtain the Q-values with different corneal diameters (3.0 mm, 4.0 mm, 5.0 mm, 6.0 mm, and 7.0 mm). Variable Q models o...

  17. Methylene blue-related corneal edema and iris discoloration.

    Science.gov (United States)

    Timucin, Ozgur Bulent; Karadag, Mehmet Fatih; Aslanci, Mehmet Emin; Baykara, Mehmet

    2016-04-01

    We report the case of a 70-year-old female patient who developed corneal edema and iris discoloration following the inadvertent use of 1% methylene blue instead of 0.025% trypan blue to stain the anterior capsule during cataract phacoemulsification surgery. Copious irrigation was performed upon realization of incorrect dye use. Corneal edema and iris discoloration developed during the early postoperative period and persisted at 24-months follow-up. However, keratoplasty was not required. The intracameral use of 1% methylene blue has a cytotoxic effect on the corneal endothelium and iris epithelium. Copious irrigation for at least 30 min using an anterior chamber maintainer may improve outcomes. PMID:27224079

  18. Intraocular Lens Power Calculation after Corneal Refractive Surgery

    Directory of Open Access Journals (Sweden)

    Mohammad-Ali Javadi

    2012-01-01

    Full Text Available Purpose: To report refractive outcomes following phacoemulsification (PE and posterior chamber intraocular lens (PCIOL implantation in eyes with previous corneal refractive surgery. Methods: In this retrospective comparative study, 18 consecutive eyes of 14 patients with previous keratorefractive surgery for myopia including photorefractive keratectomy (PRK, 6 eyes; 33.3% and laser in situ keratomileusis (LASIK, 12 eyes; 66.7% underwent PE+PCIOL. Computerized corneal topography was employed to determine the flattest keratometric reading within the 3-mm central zone. This value was inserted into the Sanders-Retzlaff-Kraff/T (SRK/T formula to calculate IOL power. IOL power selected for implantation was 1 D greater than the calculated value described above. Results: Mean age and follow-up period were 54.1±11.5 years and 29.9±26.3 months, respectively. Mean implanted lens power was 18.56±3.86 D which was not significantly different from mean back-calculated IOL power for target refraction (19.04±4.16 D (P=0.28. There was no significant difference between mean target refraction (-0.94±0.52 D and achieved postoperative spherical equivalent refractive error (-0.62±1.06 at final follow-up (P=0.28. The achieved spherical equivalent refractive error was within ±0.50 D of intended refraction in 8 (44.4% eyes, within ±1.0 D in 11 (61.1% eyes, and within ±2.0 D in 16 (88.9% eyes. In a subgroup of patients (5 eyes with complete pre-refractive surgery data, the difference between post-refractive surgery keratometry method and all other methods (P=0.02 and between the current method and the Feiz-Mannis method (P=0.01 was statistically significant. Conclusion: The method suggested herein is simple and independent of pre-refractive surgery data with results comparable to other commonly used methods.

  19. Genetics Home Reference: lattice corneal dystrophy type II

    Science.gov (United States)

    ... Diagnosis & Management These resources address the diagnosis or management of lattice corneal dystrophy type II: American Foundation for the Blind: Living with Vision Loss Genetic Testing Registry: Meretoja syndrome Merck Manual ...

  20. Corneal depositions in tyrosinaemia type I during treatment with Nitisinone.

    Science.gov (United States)

    Wisse, Robert P L; Wittebol-Post, Dienke; Visser, Gepke; van der Lelij, Allegonda

    2012-01-01

    We present a 17-year-old boy, diagnosed with tyrosinaemia type I at an age of 7 months, with new complaints of severe intermittent photophobia and burning eyes. His tyrosinaemia type I is treated with nitisinone and a protein-restricted diet. Dietary compliance is low since he entered puberty. His ocular complaints are attributable to subepithelial corneal deposits, resembling the common corneal phenotype of tyrosinaemia type II. Serum tyrosine levels were markedly elevated. Tyrosinaemia is a metabolic disease of tyrosine metabolism, subdivided into two types. Corneal deposits and photophobia are cardinal features of untreated tyrosinaemia type II, but not of type I. Novel treatment strategies (with nitisinone) for type I tyrosinaemia lead to a phenotype comparable with type II, including these corneal deposits. At follow-up visits his ocular complaints unfortunately remained unchanged, though he states his dietary compliance improved through the years. PMID:23203167

  1. Putative Corneal Neuralgia Responding to Vitamin D Supplementation

    Directory of Open Access Journals (Sweden)

    Eric L. Singman

    2013-09-01

    Full Text Available A patient with putative corneal neuralgia was incidentally discovered to have hypovitaminosis D. Supplementation of vitamin D appears to have led to a resolution of the patient's pain, whereas other efforts to treat the patient were unsuccessful.

  2. Corneal injury and the appearance of various enzymes in tears

    Czech Academy of Sciences Publication Activity Database

    Čejková, Jitka; Štípek, S.; Ardan, Taras; Crkovská, J.; Midelfart, A.

    Prague, 2002. s. 33. [International Symposium on Cornea and Contact Lenses .. 07.12.2002-10.12.2002, Prague] Institutional research plan: CEZ:AV0Z5039906 Keywords : corneal injury Subject RIV: FF - HEENT, Dentistry

  3. Use of Bevacizumab in the Treatment of Corneal Neovascularization

    Directory of Open Access Journals (Sweden)

    Tuba Çelik

    2015-01-01

    Full Text Available Corneal neovascularization is a serious condition resulting in various degrees of vision loss. The abnormal vascularization blocks the light depending on the corneal scarring, thus it reduces the visual acuity. Corneal neovascularization occurs as a result of shifting the balance between the angiogenic and the antiangiogenic factors on behalf of the angiogenic factors. Vascular endothelial growth factor (VEGF is the primary mediator of angiogenesis. Anti-VEGF agents are widely used in the treatment of neovascular age-related macular degeneration, diabetic retinopathy, macular edema, neovascular glaucoma, and the other neovascular diseases. These agents are also effective in the treatment of corneal neovascularization. Herein, we discuss the most known anti-VEGF agent bevacizumab and its administration routes, the efficiency and the complications. (Turk J Ophthalmol 2015; 45: 31-36

  4. Another Risk From Cigarette Smoking: Corneal Burn

    Directory of Open Access Journals (Sweden)

    Volkan Hürmeriç

    2012-12-01

    Full Text Available A 21-year-old male presented with corneal injury in his left eye after one of his friends had moved his arm backwards and accidentally hit his eye with the lit end of a cigarette. Slit lamp examination revealed epithelial defect and significant stromal edema at the superior temporal quadrant of the cornea. Cigarette ashes were noted in his lashes and inferior conjunctival fornix at the initial examination in the emergency service. 6 weeks after the injury, slit lamp examination revealed stromal thinning and haze in the temporal part of the cornea. His best spectacle-corrected distance visual acuity was 20/25 with a refractive error of -6.75x135 diopters in the left eye. Our case demonstrates that ocular thermal injury due to cigarette smoking can cause serious damage to the ocular tissues. (Turk J Oph thal mol 2012; 42: 484-5

  5. The phacoemulsification procedure. II. Corneal endothelial changes.

    Science.gov (United States)

    Polack, F M; Sugar, A

    1976-06-01

    The effect of phacoemulsification, with the Cavitron-Kelman instrument, on the corneal endothelium of rabbit and cats was studied by scanning electron microscopy and nitroblue tetrazolium staining. The various steps of the procedure were examined separately. Irrigation of the anterior chamber of the eye with balanced salt solution (Plasma-Lyte) for ten minutes caused no cell damage. Ultrasound and irrigation alone for four to six minutes caused increased permeability to NBT. Edema of endothelial cells and cell junction disruption occurred after eight minutes of anterior chamber irrigation with Plasma-Lyte. Uncomplicated phacoemulsification produced moderate cellular edema with scattered loss of endothelial cells. Destruction of endothelial cells was frequent after phacoemulsification, it appeared to be due to lens nucleus manipulation in the anterior chamber, instrumentation, and needle contact. From two to five days postoperatively, intercellular edema, altered cell morphology, and mosaic pattern were seen. However, it gradually recovered and seven to ten days later the endothelium appeared normal. PMID:931690

  6. Estimation of Postmortem Interval by Detecting Thickness of Cornea Using Ultrasonic Method%超声法测量角膜厚度推断死亡时间

    Institute of Scientific and Technical Information of China (English)

    吕国丽; 姜富学; 许心舒; 蒋拥军; 李志刚; 王欣; 石河; 余礼聪; 许传超

    2012-01-01

    目的 用超声法测量角膜厚度,探索其死后变化规律.方法 11只家兔随机分为两组,分别为角膜上皮完整组及去角膜上皮组.后者采用机械刮除法去除角膜上皮.利用超声测厚仪连续监测两组动物的死后多个时间点的角膜厚度,并对角膜厚度变化与死亡时间进行相关回归分析.结果 超声法测量角膜上皮完整组死后兔角膜厚度的变化值与死亡时间呈非线性相关,且具有较强的相关性,相关系数为0.922,而去角膜上皮组的相关系数为0.822.结论 超声法测量角膜厚度对推断早期死亡时间具有较可靠的应用前景.完整的角膜上皮对于超声测量角膜厚度具有关键作用.%Objective To explore the postmortem changes of cornea thickness measured by ultrasonic pachymetry. Methods Eleven rabbits were randomly divided into two groups: one group with intact corneal epithelium and another group without intact corneal epithelium. In the later group, the corneal epithelium of the rabbit was scraped using mechanical elimination method. The corneal thickness was monitored continuously by ultrasonic pachymetry at several postmortem interval points in rabbits of the two groups. The changes of corneal thickness and postmortem interval were explored by relative regression analysis. Results The thickness of the cornea showed a strong non-linear correlation with the postmortem interval in the group with intact corneal epithelium. The group with intact corneal epithelium showed the correlation coefficient 0.922 and the group without intact corneal epithelium showed the correlation coefficient 0.822, respectively. Conclusion The corneal thickness measured by ultrasonic pachymetry shows a potential value for estimating early postmortem interval. The intact corneal epithelium is a crucial factor for the measurement of cornea thickness by ultrasonic pachymetry.

  7. Evaluation of the PAR corneal topography system

    Science.gov (United States)

    Jindal, Prateek; Cheung, Susan; Pirouzian, Amir; Keates, Richard H.; Ren, Qiushi

    1995-05-01

    The purpose of this study was to evaluate the raster photogrammetry based Corneal Topography System by determining: inter-operator variability, reproducibility of images, effects of defocused and decentered images, and the precision of data at different optical zones. 4 human cadaver eyes were used to study the inter-operator variability. To study the reproducibility of images, 3 human cadaver eyes and a test surface doped with flourescine (provided by PAR Vision Systems Corporation) were focused and their images taken four successive times. Defocused and decentered images were taken of 4 human cadaver eyes and four times of the test surface mentioned above. The precision of defocused/decentered cadaver eyes was evaluated at the following optical zones: 3 mm, 4 mm, 5 mm, and 6 mm. All human cadaver eyes used in the above experiments had their epithelial layer removed before imaging. Average inter-operator variability was 0.06 D. In reproducibility attempts, there was an average deviation of 0.28 D for the human cadaver eyes and 0.04 D for the test surface. The defocused and decentered test surface gave an average deviation of 0.09 D. Defocused and decentered cadaver eyes resulted in an average deviation of 0.52 D, 0.37 D, 0.24 D, and 0.22 D at optical zones of 3 mm, 4 mm, 5 mm, and 6 mm, respectively. The imaging method employed by PAR Vision Systems Corporation virtually eliminates inter-operator variability. The PAR Corneal Topography System's clinical usefulness, however, could be improved by improving the reproducibility of images, decreasing the sensitivity to spatial alignment, and increasing accuracy over smaller optical zones.

  8. Clinical utility of the KAMRA corneal inlay

    Directory of Open Access Journals (Sweden)

    Naroo SA

    2016-05-01

    Full Text Available Shehzad Anjam Naroo, Paramdeep Singh Bilkhu Ophthalmic Research Group, School of Life & Health Sciences, Aston University, Birmingham, UK Abstract: The treatment of presbyopia has been the focus of much scientific and clinical research over recent years, not least due to an increasingly aging population but also the desire for spectacle independence. Many lens and nonlens-based approaches have been investigated, and with advances in biomaterials and improved surgical methods, removable corneal inlays have been developed. One such development is the KAMRA™ inlay where a small entrance pupil is exploited to create a pinhole-type effect that increases the depth of focus and enables improvement in near visual acuity. Short- and long-term clinical studies have all reported significant improvement in near and intermediate vision compared to preoperative measures following monocular implantation (nondominant eye, with a large proportion of patients achieving Jaeger (J 2 to J1 (~0.00 logMAR to ~0.10 logMAR at the final follow-up. Although distance acuity is reduced slightly in the treated eye, binocular visual acuity and function remain very good (mean 0.10 logMAR or better. The safety of the inlay is well established and easily removable, and although some patients have developed corneal changes, these are clinically insignificant and the incidence appears to reduce markedly with advancements in KAMRA design, implantation technique, and femtosecond laser technology. This review aims to summarize the currently published peer-reviewed studies on the safety and efficacy of the KAMRA inlay and discusses the surgical and clinical outcomes with respect to the patient’s visual function. Keywords: presbyopia, refractive surgery, implants, cornea

  9. Dynamic Corneal Surface Mapping with Electronic Speckle Pattern Interferometry

    Science.gov (United States)

    Iqbal, S.; Gualini, M. M. S.

    2013-06-01

    In view of the fast advancement in ophthalmic technology and corneal surgery, there is a strong need for the comprehensive mapping and characterization techniques for corneal surface. Optical methods with precision non-contact approaches have been found to be very useful for such bio measurements. Along with the normal mapping approaches, elasticity of corneal surface has an important role in its characterization and needs to be appropriately measured or estimated for broader diagnostics and better prospective surgical results, as it has important role in the post-op corneal surface reconstruction process. Use of normal corneal topographic devices is insufficient for any intricate analysis since these devices operate at relatively moderate resolution. In the given experiment, Pulsed Electronic Speckle Pattern Interferometry has been utilized along with an excitation mechanism to measure the dynamic response of the sample cornea. A Pulsed ESPI device has been chosen for the study because of its micron-level resolution and other advantages in real-time deformation analysis. A bovine cornea has been used as a sample in the subject experiment. The dynamic response has been taken on a chart recorder and it is observed that it does show a marked deformation at a specific excitation frequency, which may be taken as a characteristic elasticity parameter for the surface of that corneal sample. It was seen that outside resonance conditions the bovine cornea was not that much deformed. Through this study, the resonance frequency and the corresponding corneal deformations are mapped and plotted in real time. In these experiments, data was acquired and processed by FRAMES plus computer analysis system. With some analysis of the results, this technique can help us to refine a more detailed corneal surface mathematical model and some preliminary work was done on this. Such modelling enhancements may be useful for finer ablative surgery planning. After further experimentation

  10. Posterior corneal curvature changes following Refractive Small Incision Lenticule Extraction

    OpenAIRE

    Ganesh, Sri

    2015-01-01

    Sri Ganesh, Utsav Patel, Sheetal Brar Phaco and Refractive Surgery Department, Nethradhama Superspeciality Eye Hospital, Bengaluru, Karnataka, India Purpose: To compare the posterior corneal curvature changes, in terms of corneal power and asphercity, following Refractive Small Incision Lenticule Extraction (ReLEx SMILE) procedure for low, moderate, and high myopia.Methods: This retrospective, non randomized, comparative, interventional trial; included 52 eyes of 26 patients, divided in thr...

  11. Corneal depositions in tyrosinaemia type I during treatment with Nitisinone

    OpenAIRE

    Wisse, Robert P L; Wittebol-Post, Dienke; Visser, Gepke; Lelij, Allegonda

    2012-01-01

    We present a 17-year-old boy, diagnosed with tyrosinaemia type I at an age of 7 months, with new complaints of severe intermittent photophobia and burning eyes. His tyrosinaemia type I is treated with nitisinone and a protein-restricted diet. Dietary compliance is low since he entered puberty. His ocular complaints are attributable to subepithelial corneal deposits, resembling the common corneal phenotype of tyrosinaemia type II. Serum tyrosine levels were markedly elevated. Tyrosinaemia is a...

  12. Impact of Facial Conformation on Canine Health: Corneal Ulceration

    OpenAIRE

    Rowena M A Packer; Hendricks, Anke; Burn, Charlotte C.

    2015-01-01

    Concern has arisen in recent years that selection for extreme facial morphology in the domestic dog may be leading to an increased frequency of eye disorders. Corneal ulcers are a common and painful eye problem in domestic dogs that can lead to scarring and/or perforation of the cornea, potentially causing blindness. Exaggerated juvenile-like craniofacial conformations and wide eyes have been suspected as risk factors for corneal ulceration. This study aimed to quantify the relationship betwe...

  13. Delayed-onset endophthalmitis associated with corneal suture infections

    OpenAIRE

    Henry, Christopher R.; Flynn Jr., Harry W.; Miller, Darlene; Schefler, Amy C; Forster, Richard K.; Alfonso, Eduardo C.

    2013-01-01

    Background The purpose of the current study was to report the microbiology, risk factors, and treatment outcomes in patients with delayed-onset endophthalmitis associated with corneal suture infections. For this retrospective consecutive case series, a search of the ocular microbiology department database was performed to identify all patients with positive corneal and intraocular cultures (anterior chamber and/or vitreous) between 01 January 1995 and 01 January 2010. A subset of patients wit...

  14. Temporal, 3-dimensional, cellular anatomy of corneal wound tissue.

    OpenAIRE

    Jester, J V; Petroll, W M; Barry, P. A.; Cavanagh, H D

    1995-01-01

    We have evaluated temporally the 3-dimensional cellular anatomy of corneal wound tissue in the rabbit eye using in vivo tandem scanning confocal microscopy. In vivo microscopic studies showed that corneal fibroblast migrated into the wound as an interconnected cellular meshwork with long, thin, randomly oriented cell processes. Interconnection of fibroblasts was further confirmed by localisation of monoclonal antibodies to connexin 43 which demonstrated prominent staining of putative gap junc...

  15. The Effect of Anterior Stromal Puncture Using Q-Switched Nd:YAG Laser on Corneal Wound Healing

    OpenAIRE

    Hamdy Abdelaziz, Mohamed; Fouad Ghoneim, Dina; Abdelkawi Ahmed, Salwa; Taher, Ibraheim Mohyeldin; Abdel- Salam, Ahmed Medhat

    2014-01-01

    Introduction: Recurrent corneal erosion occurs when the wounded corneal epithelium failed to adhere to the underlying stroma. Therefore, this work aimed to assess the effect of treatment of corneal injury using Q- switched Nd:YAG laser.

  16. Evaluation of retinal nerve fiber layer thickness measurement following laser in situ keratomileusis using scanning laser polarimetry

    Directory of Open Access Journals (Sweden)

    Dada Tanuj

    2007-01-01

    Full Text Available Aim: To evaluate the effect of laser-assisted in situ keratomileusis (LASIK on the measurement of retinal nerve fiber layer thickness by scanning laser polarimetry using customized corneal compensation in myopes. Materials and Methods: Scanning laser polarimetry was performed on 54 eyes of 54 healthy patients with myopia using the glaucoma diagnostics variable corneal compensation (GDx VCC instrument (Laser Diagnostic Technologies, San Diego, California before and a week after LASIK. The various parameters were compared using the Student′s t test. Results: No statistically significant change was observed in any of the retinal nerve fiber layer parameters before and after LASIK. Conclusions: While the measurement of retinal nerve fiber layer thickness by scanning laser polarimetry is affected by anterior segment birefringent properties and LASIK would be expected to produce changes in the same, customized corneal compensation using the GDx VCC seems to adequately compensate for these changes.

  17. Inhibition of Corneal Neovascularization by Topical and Subconjunctival Tigecycline

    Directory of Open Access Journals (Sweden)

    Sertan Goktas

    2014-01-01

    Full Text Available Objective. To investigate the effects of topical and subconjunctival tigecycline on the prevention of corneal neovascularization. Materials and Methods. Following chemical burn, thirty-two rats were treated daily with topical instillation of 1 mg/mL tigecycline (group 1 or subconjunctival instillation of 1 mg/mL tigecycline (group 3 for 7 days. Control rats received topical (group 2 or subconjunctival (group 4 0.9% saline. Digital photographs of the cornea were taken on the eighth day after treatment and analyzed to determine the percentage area of the cornea covered by neovascularization. Corneal sections were analyzed histopathologically. Results. The median percentages of corneal neovascularization in groups 1 and 3 were 48% (95% confidence interval (CI, 44.2–55.8% and 33.5% (95% CI, 26.6–39.2%, respectively. The median percentages of corneal neovascularization of groups 1 and 3 were significantly lower than that of the control group (P=0.03 and P<0.001, resp.. Histologic examination of samples from groups 1 and 3 showed lower vascularity than that of control groups. Conclusion. Topical and subconjunctival administration of tigecycline seems to be showing promising therapeutic effects on the prevention of corneal neovascularization. Furthermore, subconjunctival administration of tigecycline is more potent than topical administration in the inhibition of corneal neovascularization.

  18. Analysis of corneal esthesia in patients undergoing photorefractive keratectomy

    Directory of Open Access Journals (Sweden)

    Elmar Torres Neto

    2015-12-01

    Full Text Available ABSTRACT Purpose: To quantitatively analyze corneal esthesia in patients undergoing photorefractive keratectomy (PRK surgery. Methods: Forty-five patients selected for PRK in one eye underwent corneal esthesia using a Cochet-Bonnet esthesiometer preoperatively and 30 and 90 days postoperatively. Patients with a refractive diopter error of 4 or greater received intraoperative 0.02% mitomycin C for 20 s. Results: Twenty-four (53.3% of the 45 eyes received intraoperative 0.02% mitomycin. Decreased sensitivity was observed on postoperative day 30. By postoperative day 90, corneal esthesia had normalized but remained 14.9% lower than preoperative levels. In the mitomycin group, no recovery of corneal esthesia to normal sensitivity levels was observed. The mean esthesiometer level was 39.2 mm on postoperative day 90 (P<0.001. Conclusions: The results of the present study demonstrate recovery of corneal esthesia to normal levels at 90 days postoperatively in patients who did not receive mitomycin C. In patients administered mitomycin C, a 23.59% reduction in the corneal touch threshold was observed compared with preoperative levels indicating a failure of recovery to normal levels.

  19. Assessment of anterior and posterior corneal indices using two Scheimpflug analyzers

    Directory of Open Access Journals (Sweden)

    Daoud Charbel Fahd

    2014-01-01

    Full Text Available Purpose: To assess the agreement between the elevation and curvature measurements of the anterior and posterior corneal surfaces obtained using the Galilei Dual Scheimpflug Analyzer and those obtained using the Pentacam single Scheimpflug system. Methods: This prospective, noninterventional, diagnostic study was conducted at the Department of Ophthalmology at the American University of Beirut (Medical Center and included 60 eyes of 60 consecutive patients. Measurements were obtained using 2 different Scheimpflug analyzers (Galilei and Pentacam. The best-fit sphere was set at 8 mm in both machines. Pachymetry (CCT, anterior elevation (AE and posterior elevation (PE, and curvature were assessed. Pearson's correlation coefficients, comparison of means, and Bland-Altman plots were used to evaluate agreement between the 2 systems. Results: The average CCT (at the corneal apex was 533 ± 35 µm and 532 ± 37 µm (p=0.980, the average central AE was 1.25 ± 3.95 µm and 2.29 ± 5.28 µm (p=0.964, and the average central PE was 4.19 ± 8.18 µm and 5.42 ± 14.05 (p=0.956 µm with the Galilei and Pentacam, respectively. Conclusion: The Scheimpflug analyzers correlated well in the assessment of pachymetry, elevation, and curvature.

  20. Corneal Limbal Microenvironment Can Induce Transdifferentiation of Hair Follicle Stem Cells into Corneal Epithelial-like Cells

    OpenAIRE

    Blazejewska, Ewa Anna; Schlötzer-Schrehardt, Ursula; Zenkel, Matthias; Bachmann, Björn; Chankiewitz, Erik; Jacobi, Christina; Kruse, Friedrich E.

    2009-01-01

    The aim of this study was to investigate the transdifferentiation potential of murine vibrissa hair follicle (HF) stem cells into corneal epithelial-like cells through modulation by corneal- or limbus-specific microenvironmental factors. Adult epithelial stem cells were isolated from the HF bulge region by mechanical dissection or fluorescence-activated cell sorting using antibodies to α6 integrin, enriched by clonal expansion, and subcultivated on various extracellular matrices (type IV coll...

  1. Comparison of the Keratometric Corneal Astigmatic Power after Phacoemulsification: Clear Temporal Corneal Incision versus Superior Scleral Tunnel Incision

    OpenAIRE

    Yongqi He; Siquan Zhu; Ming Chen; Dejiao Li

    2009-01-01

    Objective. This is prospective randomized control trial to compare the mean keratometric corneal astigmatism diopter power (not surgical induced astigmatism) among preop and one-month and three-month postop phacoemulcification of either a clear temporal corneal incision or a superior scleral tunnel Incision, using only keratometric astigmatic power reading to evaluate the difference between the two cataract surgery incisions. Methods. 120 patients (134 eyes) underwent phacoemulcification were...

  2. Comparison of comeal thickness measurements using pentacam, orbscan Ⅱ, and A-ultrasonic pachymetry in myopia%Pentacam、Orbscan Ⅱ和A超测量中央角膜厚度的分析

    Institute of Scientific and Technical Information of China (English)

    雷玉琳; 郑秀云; 党光福; 刘素美

    2011-01-01

    日的比较Pentacam、Orbscan Ⅱ和A超三种角膜测犀仪检测近视眼中央角膜厚度的差异.方法 分别用Pcntacam眼前节分析仪、Orbscan Ⅱ角膜地形图仪及A超对角膜厚度进行检测,并将测量值进行统计学分析.结果 Pentacam测得角膜厚度为(536.01±32.33)μm,Orbscan Ⅱ测得近视眼角膜厚度为(539.21±37.45)μm,A超测得角膜厚度为(535.39±31.46)μm.Orbscan Ⅱ测量值与Pentacam和A超测量值差异均有统计学意义(P<0.001),Pentacam与A超测量值间的比较差异无统计学意义(P=0.095).三种测厚结果 显示高度正相关,Orb-scan-Pentacam、Orbscan-A超、Pcntacam-A超的相关系数r分别为0.917、0.906、0.965,回归方程如下:Orbscan(μm)=-30.699+[1.0622×Pentacam(μm)],Orbscan(μm)=-38.599+[1.0792×A超(μm)],Pen-tacam(μm)=5.424+[0.9919×A超(μm)].结论 在检测中央角膜厚度方面,Orbscan Ⅱ与Pcntacam及A超不可替代使用,Pentacam与A超可相互替代使用.%Objective To compare the central corneal thickness measurements using pentacam, orbscan Ⅱ and A-ultrasonic pachymeter in myopic eyes. Methods Central comeal thickness was measured and analyzed with pentacam, orbscan Ⅱ, and A-ultrasonics. Results The mean central corneal thickness measured by pentacam,orbscan Ⅱ ,and A-ultrasonics were (536.01 ±32.33) μm, (539.21 ±37.45)μm,and(535.39 ±31.46)μm,respectively. Significant difference was found between orbscan Ⅱ and pentacam or A-ultrasonic ( P < 0. 001 ). No significant difference was found between pentacam and A-ultrasonic(P =0.095 ). Positive relationships were found in the results of corneal thickness among the 3 methods. The correlation coefficient r of (orbscan-pentacam), (orbscan-A-ultrasonic), (pentacam-A-ultrasonic) were correpondinging 0. 917,0. 906, and 0. 965. The regression equations were "orbscan (μm) = - 30.699 + [ 1.062 2 × pentacam(μm)]", "orbscan(μm) =-38.599 + [1.0792 × A-ultrasonic (μm)]", and "pentacam(μm) = 5.424 + [ 0

  3. Choroidal thickness and central serous chorioretinopathy:a case-control study and Meta-analysis%脉络膜厚度与CSCR的病例对照研究与Meta分析

    Institute of Scientific and Technical Information of China (English)

    叶汉元; 杨安怀

    2015-01-01

    目的:定量分析中心性浆液性脉络膜视网膜病变( central serous chorioretinopathy,CSCR)患者黄斑中心凹下脉络膜厚度( subfoveal choroidal thickness,SFCT)改变。  方法:采用病例对照研究及Meta分析。连续的CSCR患者46例纳入研究,CSCR患者散瞳后前置镜眼底检查,荧光素眼底血管造影和吲哚菁绿血管造影检查确诊。选择同期年龄、性别、屈光度及眼轴匹配的正常人62例62眼作为正常对照组。用加强成像深度扫描OCT检测并比较CSCR组及对照组SFCT。单因素和多因素分析 SFCT 与各临床资料之间的关系。 Meta分析用Stata软件计算两组之间的加权均数差。  结果:CSCR患者的平均SFCT为397.34±83.91μm,正常对照组为274.48±62.57μm。 CSCR组SFCT较对照组明显增厚,差异有统计学意义(P  结论:CSCR患者黄斑中央凹下脉络膜较正常眼厚,增厚的SFCT与CSCR诊断存在相关性。%AIM:To investigate the changes of subfoveal choroidal thickness ( SFCT ) in central serous chorioretinopathy ( CSCR) eyes and to compare them with normal control eyes. METHODS: This was a case-control study and a Meta-analysis. Forty - six CSCR patients diagnosed by the fundus pre - set lens, fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were enrolled in this study. Sixty two age-, sex-, diopter- and axial length-matched 62 normal subjects ( 62 eyes ) were enrolled in this study as the control group. Using enhanced depth imaging optical coherence tomography ( EDI-OCT) , SFCT of CSCR eyes and normal control eyes were measured and compared. Univariate and multivariate linear regression analysis were performed to assess the association between SFCT and clinical factors. The Meta - analysis were conducted using the Stata software package to calculate the summary weighted mean differences ( WMDs) . RESULTS:The mean SFCT of the CSCR group and the normal control group was 397. 34±83. 91μm and

  4. 近视性高度屈光参差眼屈光参数和角膜生物学参数的研究%Research of refractive index and corneal biological parameter in high myopic anisometropia eyes

    Institute of Scientific and Technical Information of China (English)

    许爱琴; 方海珍

    2011-01-01

    Objective To investigate the differences of refractive index and corneal biological parameter in high myopic anisometropia.Methods Twenty three subjects who suffered anisometropia (spherical equivalent ≥6.00 D) were selected.For each subject,corneal hysteresis (CH) was measured by ORA (Ocular Response Analyzer),central corneal thickness (CCT) was measured by OCT,average keratometer value (mean K) and ocular axial length (AL) were measured by Zeiss IOL-Master,the results were tested by paired t-test and multiple linear regression.Result The differences of mean K,CCT for two eyes were not significant (P >0.05).Mean AL was (28.34± 1.10) mm (SD) in high myopic eyes compared with (24.53± 0.70) mm in the fellow eye,the difference was statistically significant (P <0.0001).The mean hysteresis in high myopic eyes and the fellow eyes was (10.00± 1.61)mmHg and (10.96± 1.38) mmHg,respectively; the difference was statistically significant (P <0.0001).The relationship between CH and AL and CCT was statistically significant (P <0.05).Conclusions Under the same gene and environment,the corneal hysteresis value is significantly lower in high myopia,which has no thinner cornea.It may be due to the change in cornea microstructure as a result of axial abnormal elongation.%目的 分析和研究近视性的高度屈光参差眼屈光参数及角膜生物学参数的差异性.方法 对23名近视性的高度屈光参差患者(双眼等效球镜SE差≥6.00D),用眼反应分析仪(Ocular Response Analyzer,ORA)测量角膜滞后性(Corneal Hyteresis,CH),用改进的光学相干断层扫描仪(OCT-3)测量中央角膜厚度(CCT),用IOL-Master测量角膜曲率(mean K)及眼轴长度(AL).统计处理采用配对t检验和多元线性回归分析.结果 近视程度高度眼平均AL(28.34±1.10)mm,低度眼平均AL( 24.53±0.70)mm,差异有统计学意义(P<0.01).双眼角膜平均曲率K差异无统计学意义(P>0.05).双眼CCT差异无统计学意义(P>0.05).

  5. Manual intrastromal corneal keratotomy: An alternate encouraging approach for refractive error correction

    Directory of Open Access Journals (Sweden)

    Saravana Kodandapani

    2014-01-01

    Full Text Available Results of femtosecond based intrastromal astigmatic keratotomy have been reported to be encouraging for correction of Astigmatism. We report a new surgical technique-manual intrastromal corneal keratotomy (MICK for correction of simple refractive astigmatism (−1.5 DC against the rule. The technique involves the creation of a 100 μm thickness corneal flap creation using Moria M2 evolution LSK MicroKeratome and 300 μm depth, 4 mm long manual transverse astigmatic keratotomy on both sides of the steep axis 3 mm from the pupillary center along with four incision peripheral radial keratotomy outside the optic zone (based on the mesopic pupil. The flap was repositioned and routine post-operative regimen was followed. Patient achieved 20/20 vision in both eyes post-operatively on the first day, which was maintained even at the 1 month follow-up. This simple technique could be useful as an alternative method for correction of refractive errors in patients not suitable for excimer and/or femtosecond laser treatment.

  6. New techniques to improve classical corneal collagen cross-linking treatment

    Institute of Scientific and Technical Information of China (English)

    Li Na; Peng Xiujun; Fan Zhengjun; Xia Yu; Wu Tengfei

    2014-01-01

    Objective The aim of this review is to comprehensively and unbiasedly summarize the improvements in the techniques for classical corneal collagen cross-linking (CXL) by covering the reasons for this improvement,measure,and effect to approach the future direction of the CXL.Data sources All articles used in this review were mainly retrieved from the PubMed database.Study selection Original articles and reviews were selected if they were related to the improvement in the technique of classical CXL.Data were mainly extracted from 94 articles,which are listed in the reference section of this review.Results This innovative research involves every step such as instrument preparation,epithelial management,riboflavin instillation,and UVA irradiation.These clinical and experimental results seem promising.Conclusions CXL treatment is the only recent promising method for preventing the progress of keratoconus.The limitations and potential complications that accompany classical CXL such as corneal thickness limitations,ultraviolet-A (UVA) light injury,and the impact of de-epithelialization encourage people to research new improvements in techniques.While this research needs to be further investigated,we hope our review can help related researchers and patients.

  7. Precision and agreement of corneal power measurements obtained using a new corneal topographer OphthaTOP.

    Directory of Open Access Journals (Sweden)

    Jinhai Huang

    Full Text Available To evaluate repeatability and reproducibility of anterior corneal power measurements obtained with a new corneal topographer OphthaTOP (Hummel AG, Germany and agreement with measurements by a rotating Scheimpflug camera (Pentacam HR, Oculus, Germany and an automated keratometer (IOLMaster, Carl Zeiss Meditec, Germany.The right eyes of 79 healthy subjects were prospectively measured three times with all three devices. Another examiner performed three additional scans with the OphthaTOP in the same session. Within one week, the first examiner repeated the measurements using the OphthaTOP. The flat simulated keratometry (Kf, steep K (Ks, mean K (Km, J0, and J45 were noted. Repeatability and reproducibility of measurements were assessed by within-subject standard deviation (Sw, repeatability (2.77 Sw, coefficient of variation (CoV, and intraclass correlation coefficient (ICC. Agreement between devices was assessed using 95% limits of agreement (LoA.Intraobserver repeatability and interobserver and intersession reproducibility of all measured parameters showed a 2.77 Sw of 0.29 diopter or less, a CoV of less than 0.24%, and an ICC of more than 0.906. Statistically significant differences (P<0.001 were found between the parameters analyzed by the three devices, except J0 and J45. The mean differences between OphthaTOP and the other two devices were small, and the 95% LoA was narrow for all results.The OphthaTOP showed excellent intraobserver repeatability and interobserver and intersession reproducibility of corneal power measurements. Good agreements with the other two devices in these parameters were found in healthy eyes.

  8. CORNEAL HAZE FOLLOWING PHOTO REFRACT IVE KERATECTOMY

    Directory of Open Access Journals (Sweden)

    Atul

    2015-02-01

    Full Text Available To assess the incidence of corneal haze following surface ablation in (PRK in high myopic patients (≥6D. METHODS: In this prospective clinical study , 25 patients with high myopia (≥6D that is 50 eyes in total , underwent photorefractive keratectomy by Schwind Amaris 500E laser machine. At the initial presentation , each patient underwent a detailed clinical evaluation that included recording of medical history , detailed ocular history , Snellen visual acuity testing , and thorough anterior segment by slit - lamp bi o - microscopy and posterior segment examination with indirect ophthalmoscopy were done. Corneal topography and pachymetry were also done. The patient is followed up at 1week to observe for re - epithelialization and then at 1 , 3 and 6 months for observation o f haze under slit - lamp examinamination. RESULTS: In our study of 25 patients , that is 50 eyes in total were divided into 3 groups depending upon the spherical equivalence. Group 1 between 6.00 - 7.00D , group 2 between 7.00 - 8.00D , and in group 3 more than 8D (≥8.00D. Over 6months period of follow up a significant haze was noted as the patient’s refractive error increased. Out of 50 eyes , 11 eyes (84.6% with spherical equivalence of 6.00 - 7.00D (group 1 had grade 0 , 8 eyes (66.6% with spherical equivalence o f 7.00 - 8.00D (group 2 had grade 0 , and 6 eyes (24% with spherical equivalence ≥8.00D (group 3 had grade 0. Thus , the results show that there has been a significant decrease in the eyes with no corneal haze as the refractive error increased. Eyes with gr ade 1 haze in group1 were 2 (15.3% , group 2 were 3 (25% , and group 3 were 7 (28%. These results showed that the incidence of grade 1 haze increased with increase in spherical equivalence. Eyes with grade 2 haze in group 1 were 0 (0% , group 2 were 1 (8. 3% , group 3 were 10 (40%. Thus , it is seen that grade 2 haze was not noted in eyes with spherical equivalence between 6.00 - 7.00D , but were

  9. Repeatability and Reproducibility of Retinal Nerve Fiber Layer Parameters Measured by Scanning Laser Polarimetry with Enhanced Corneal Compensation in Normal and Glaucomatous Eyes

    OpenAIRE

    Mirian Ara; Antonio Ferreras; Pajarin, Ana B.; Pilar Calvo; Michele Figus; Paolo Frezzotti

    2015-01-01

    Objective. To assess the intrasession repeatability and intersession reproducibility of peripapillary retinal nerve fiber layer (RNFL) thickness parameters measured by scanning laser polarimetry (SLP) with enhanced corneal compensation (ECC) in healthy and glaucomatous eyes. Methods. One randomly selected eye of 82 healthy individuals and 60 glaucoma subjects was evaluated. Three scans were acquired during the first visit to evaluate intravisit repeatability. A different operator obtained two...

  10. Femtosecond laser assisted design of sutureless intrastromal graft as an alternative to partial thickness keratoplasty

    Science.gov (United States)

    Rossi, Francesca; Durkee, Heather; Pini, Roberto; Canovetti, Annalisa; Malandrini, Alex; Lenzetti, Ivo; Rubino, Pierangela; Leaci, Rosachiara; Neri, Alberto; Scaroni, Patrizia; Menabuoni, Luca; Macaluso, Claudio

    2014-02-01

    Minimally invasive laser assisted surgery in ophthalmology is continuously developing in order to find new surgical approaches, preserve patient tissue and improve surgical results in terms of cut precision, restoration of visual acuity, and invasiveness. In order to achieve these goals, the current approach in corneal transplant is lamellar keratoplasty, where only the anterior or posterior part of the patient's cornea is substituted depending on the lesion or pathology. In this work, we present a novel alternative approach: a case study of intrastromal sutureless transplant, where a portion of the anterior stroma of a donor cornea was inserted into the stroma of the recipient cornea, aiming to restore the correct thickness of the patient's cornea. The patient cornea was paracentrally thin, as the result of a trophic ulcer due to ocular pemphigoid. A discoid corneal graft from the anterior stroma of a donor eye was prepared: a femtosecond laser cut with a trapezoidal profile (thickness was 300 μm, minor and major basis were 3.00 and 3.50 mm, respectively). In the recipient eye, an intrastromal cut was also performed with the femtosecond laser using a specifically designed mask; the cut position was 275 μm in depth. The graft was loaded into an injector and inserted as an intrastromal presbyopic implant. The postoperative analysis evidenced a clear and stable graft that selectively restored corneal thickness in the thinned area. Intrastromal corneal transplant surgery is a minimally invasive alternative to anterior or posterior lamellar keratoplasty in select cases. We believe that Sutureless Intrastromal Laser Keratoplasty (SILK) could open up new avenues in the field of corneal transplantation by fully utilizing the potential and precision of existing lasers.

  11. Association between corneal arcus and some of the risk factors for coronary artery disease.

    OpenAIRE

    Pe'er, J; Vidaurri, J.; Halfon, S. T.; Eisenberg, S; Zauberman, H

    1983-01-01

    The relationships between coronary artery disease risk factors and corneal arcus were examined in 150 adults aged 55 years and above of both sexes and from different ethnic origins. The width of the corneal arcus was measured accurately by a digitiser, and the risk factors for coronary artery disease were examined according to the standard procedure used by the Lipid Research Clinics. The results show that the corneal arcus is more frequent in males; the frequency and size of corneal arcus ar...

  12. Bilateral Keratoconus and Corneal Hydrops Associated with Eye Rubbing in a 7-year-old Girl

    OpenAIRE

    Mahmoud-Reza Panahi-Bazaz; Farideh Sharifipour; Alireza Moghaddasi

    2014-01-01

    Purpose: To report a young child with bilateral keratoconus in the context of vernal keratoconjunctivitis (VKC) who developed bilateral corneal hydrops associated with eye rubbing, and to discuss the pathogenesis and review the pertinent literature. Case Report: A seven-year-old girl with VKC and asymmetric keratoconus developed corneal hydrops due to habitual eye rubbing. Corneal edema subsided within 16 weeks in her right eye and 9 weeks in the left eye with subsequent corneal scarring....

  13. Corneal endothelium of the Magellanic penguin (Spheniscus magellanicus) by scanning electron microscopy.

    Science.gov (United States)

    Pigatto, João A T; Laus, José L; Santos, Jaime M; Cerva, Cristine; Cunha, Luciana S; Ruoppolo, Valéria; Barros, Paulo S M

    2005-12-01

    The corneal endothelium is essential for the maintenance of the corneal transparency. The aim of this study was to examine the morphology of the endothelial surface and perform morphometric analysis of the normal corneal endothelial cells of the Magellanic penguin (Spheniscus magellanicus) using scanning electron microscopy. The present work demonstrates that the corneal endothelium of the Magellanic penguin is similar to those described in other vertebrates. PMID:17312730

  14. Surgical device for supporting corneal suturing

    Science.gov (United States)

    Ventura, Liliane; Oliveira, Gunter C. D.; De Groote, Jean-Jacques; Sousa, Sidney J. F.; Saia, Paula

    2009-02-01

    A system for ophthalmic surgery support has been developed in order to minimize the residual astigmatism due to the induced irregular shape of the cornea by corneal suture. The system projects 36 light spots, from LEDs, displayed in a precise circle at the lachrymal film of the examined cornea. The displacement, the size and deformation of the reflected image of these light spots are analyzed providing the keratometry and the circularity of the suture. Measurements in the range of 32D - 55D (up to 23D of astigmatism are possible to be obtained) and a self-calibration system has been designed in order to keep the system calibrated. Steel precision spheres have been submitted to the system and the results show 99% of correlation with the fabricant's nominal values. The system has been tested in 13 persons in order to evaluate its clinical applicability and has been compared to a commercial keratometer Topcon OM-4. The correlation factors are 0,92 for the astigmatism and 0.99 for the associated axis. The system indicates that the surgeon should achieve circularity >=98% in order to do not induce astigmatisms over 3D.

  15. Temporary corneal stem cell dysfunction after radiation therapy

    International Nuclear Information System (INIS)

    Radiation therapy can cause corneal and conjuctival abnormalities that sometimes require surgical treatment. Corneal stem cell dysfunction is described, which recovered after the cessation of radiation. Methods - A 44-year-old man developed a corneal epithelial abnormality associated with conjuctival and corneal inflammation following radiation therapy for maxillary cancer. Examination of brush cytology samples showed goblet cells in the upper and lower parts of the cornea, which showed increased fluorescein permeability, and intraepithelial lymphocytes. Impression cytology showed goblet cells in the same part of the cornea. Specular microscopy revealed spindle type epithelial cells. Patient follow up included artificial tears and an antibiotic ophthalmic ointment. The corneal abnormalities resolved after 4 months with improved visual acuity without any surgical intervention, but the disappearance of the palisades of Vogt did not recover at 1 year after radiation. Radiation therapy in this patient caused temporary stem cell dysfunction which resulted in conjunctivalisation in a part of the cornea. Although limbal stem cell function did not fully recover, this rare case suggested that medical options should be considered before surgery. (Author)

  16. Ipsilateral Lymphadenectomy to Inhibit Corneal Allograft Rejection in Rats

    Institute of Scientific and Technical Information of China (English)

    LING Shiqi; HU Yanhua

    2005-01-01

    In order to investigate the ipsilateral lymphadenectomy for inhibiting rejection in rat corneal transplantation, corneal allogenic transplantation models were established in rats. Eighteen female Wister rats were used as donors, and 36 Sprague Dawley rats as recipients. After penetrating corneal transplantation, recipients were randomly divided into 3 groups: group A (control group);group B, the ipsilateral lymphadenectomy group; group C, the bilateral lymphadenectomy group.Among 12 rats in each group, the corneas of 2 rats in each group were used for pathological study at day 14 after the transplantation, and the remaining 10 rats were used for studying corneal rejection by a slit lamp. The time points when allograft rejection occurred were recorded and mean survival time (MST) was compared. The results showed that MST in groups B and C was 46.30±9.464 days and 44.43 ± 7. 604 days, respectively, which was significantly prolonged as compared with that in group A (10.71±1. 567 days, P<0.01). There was no significant difference in MST between groups B and C (P>0.05). Itwas concluded that both bilateral and ipsilateral lymphadenectomy therapies could effectively inhibit the corneal allograft rejection. Ipsilateral lymphadenectomy is a less complex surgical procedure and is just as effective in preventing rejection.

  17. Pantoea ananatis as a Cause of Corneal Infiltrate after Rice Husk Injury

    OpenAIRE

    Manoharan, Geetha; Lalitha, Prajna; Jeganathan, Lakshmi Priya; DSilva, Sean Socrates; Prajna, N. Venkatesh

    2012-01-01

    We report a case of an agricultural worker presenting with corneal infiltrate following ocular injury with a rice husk. On examination, a superficial corneal foreign body was removed and sent for culture, which grew Pantoea ananatis. This is, to our knowledge, the first clinical case report of Pantoea ananatis causing corneal infiltrate.

  18. Mechanism of initial attachment of corneal epithelial cells to polymeric surfaces.

    Science.gov (United States)

    Steele, J G; Johnson, G; Griesser, H J; Underwood, P A

    1997-12-01

    The initial attachment of cultured bovine corneal epithelial cells and stromal fibroblasts to two oxygen-containing synthetic polymers was studied. Cultured epithelial cells and stromal fibroblasts were seeded onto two oxygen-containing surfaces: 'tissue culture' polystyrene (TCPS) and a polymer film deposited by RF plasma deposition using a methylmethacrylate monomer (MMA/FEP). To establish the mechanism of cell attachment, the effect of the selective removal of the vitronectin and fibronectin from the serum used in the culture medium was tested. The attachment of cultured epithelial cells during the first 90 min of culture was reduced by 40% (TCPS)-80% (MMA/FEP) as a result of removing vitronectin from the medium. Attachment of these cells to TCPS was reduced by 85-95% when the serum was depleted of both fibronectin and vitronectin. However, depletion of fibronectin reduced cell attachment to TCPS by 20%, whilst on MMA/FEP cell attachment was equivalent, or higher, than that for intact serum. The attachment of cultured corneal stromal fibroblasts was similarly dependent on vitronectin but less dependent on fibronectin. Therefore, for the attachment of both cultured epithelial cells and fibroblasts to oxygen-containing surfaces in the presence of serum, there is a high requirement for serum vitronectin but a lesser requirement for fibronectin. The effects of the establishment of corneal epithelial cells in culture and the site of origin of the cells, were determined. Primary isolates of epithelial cells isolated from the limbal, central or peripheral regions of the cornea were less dependent on vitronectin for initial attachment to TCPS than were these cells after several passages in culture. Furthermore, the primary isolates were dramatically less responsive to vitronectin than the cultured cells. These results indicate that the mechanism of attachment of corneal epithelial cells to TCPS varies with the culture experience of the cells. Cells that are culture

  19. Comparative study of visual acuity and aberrations after intralase femtosecond LASIK: small corneal flap versus big corneal flap

    Institute of Scientific and Technical Information of China (English)

    Ya-Li; Zhang; Lei; Liu; Chang-Xia; Cui; Ming; Hu; Zhao-Na; Li; Li-Jun; Cao; Xiu-Hua; Jing; Guo-Ying; Mu

    2014-01-01

    AIM:To study the effects of different flap sizes on visual acuity, refractive outcomes, and aberrations after femtosecond laser for laser keratomileusis (LASIK). ·METHODS: In each of the forty patients enrolled, 1 eye was randomly assigned to receive treatment with a 8.1mm diameter corneal flap, defined as the small flap, while the other eye was treated with a 8.6mm diameter corneal flap, defined as the big flap. Refractive errors, visual acuity, and higher -order aberrations were compared between the two groups at week 1, month 1 and 3 postoperatively. · RESULTS: The postoperative refractive errors and visual acuity all conformed to the intended goal. Postoperative higher -order aberrations were increased, especially in spherical aberration (Z12) and vertical coma (Z7). There were no statistically significant differences between the two groups in terms of postoperative refractive errors, visual acuity, root mean square of total HOAs (HO -RMS), trefoil 30° (Z6), vertical coma (Z7), horizontal coma (Z8), trefoil 0° (Z9), and spherical aberration (Z12) at any point during the postoperative follow-up. ·CONCLUSION: Both the small and big flaps are safe and effective procedures to correct myopia, provided the exposure stroma meets the excimer laser ablations. The personalized size corneal flap is feasible, as we can design the size of corneal flap based on the principle that the corneal flap diameter should be equal to or greater than the sum of the maximum ablation diameter and apparatus error.

  20. [Cytological changes in patients with diabetes mellitus and corneal ulcer].

    Science.gov (United States)

    Raica, D; Turlea, M; Ciocmăreanu, M; Haidar, A; Demian, C; Jinga, F

    1999-01-01

    There were studied 11 diabetic patients, insulin dependents, from 4 were with juvenile diabetes mellitus. These were hospitalized in the Dept. Ophthalm. of the City Hospital of Arad, during 1996-1998, admitted with the diagnosis of corneal ulcer. There were made samples of the gathered secretion from the level of conjunctiva and of the grataj material, gathered at the level of the edges of the corneal ulcer. All samples were stained with the BPT-Drăgan method. There are described cytologic alterations, insisting on details that indicate the severity of the corneal disease. There are taken into consideration cytologic aspects in relationship with the clinical outcome of the disease, pointing out the cellular alterations which announce a nonfavourable prognosis. Cytologic results can improve the diagnosis and they are involved in therapeutic schedule. PMID:10641114

  1. Corneal wound healing is compromised by immunoproteasome deficiency.

    Directory of Open Access Journals (Sweden)

    Deborah A Ferrington

    Full Text Available Recent studies have revealed roles for immunoproteasome in regulating cell processes essential for maintaining homeostasis and in responding to stress and injury. The current study investigates how the absence of immunoproteasome affects the corneal epithelium under normal and stressed conditions by comparing corneas from wildtype (WT mice and those deficient in two immunoproteasome catalytic subunits (lmp7(-/-/mecl-1(-/-, L7M1. Immunoproteasome expression was confirmed in WT epithelial cells and in cells of the immune system that were present in the cornea. More apoptotic cells were found in both corneal explant cultures and uninjured corneas of L7M1 compared to WT mice. Following mechanical debridement, L7M1 corneas displayed delayed wound healing, including delayed re-epithelialization and re-establishment of the epithelial barrier, as well as altered inflammatory cytokine production compared to WT mice. These results suggest that immunoproteasome plays an important role in corneal homeostasis and wound healing.

  2. Synchronous interferometric demodulation of Placido mires applied to corneal topography

    CERN Document Server

    Servin, Manuel

    2012-01-01

    This paper presents a novel digital interferometric method to demodulate Placido fringe patterns. This is a synchronous method which uses a computer-stored conic-wavefront as demodulating reference. Here we focuses on the experimental aspects to phase-demodulate Placido mires applied to corneal topography. This synchronous method is applied to two topographic Placido images and their de-modulated corneal-slope deformation is estimated. This conic-interferometric method is highly robust against typical "noisy" signals in Placido topography such as: reflected eyelashes and iris structures. That is because the eyelashes and the iris structure are high frequency "noisy" signals corrupting the reflected Placido mire, so they are filtered-out by this method. Digital synchronous interferometry is here applied for the first time to demodulate corneal topographic concentric-rings images (Patent pending at the USPTO).

  3. Tectonic corneal graft for conjunctival rhinosporidiosis with scleral melt

    Directory of Open Access Journals (Sweden)

    Pushpa Jacob

    2011-01-01

    Full Text Available A 16 year old girl presented with irritation and watering of the right eye for 3 months. On examination, the superior perilimbal sclera was ectatic with incarcerated uveal tissue covered by conjunctiva. The conjunctiva showed discreet, yellow white mucoid spots. Excision biopsy of the conjunctiva showed subepithelial spherules of sporangia containing numerous endospores, suggestive of rhinosporidiosis. Diathermy was applied to flatten the staphyloma. The ectatic area was covered with a corneal patch graft. The patient was started on prednisolone acetate eye drops and oral dapsone for 6 months. Corneal graft was well incorporated and conjunctivalized by 3 months. Since the graft was not seen within the palpebral aperture, there was good cosmetic result. The corneal graft had the added advantage of transparency which allowed visualization of the underlying tissue to diagnose early recurrence. There was no recurrence at 6 months.

  4. Measurement of corneal tangent modulus using ultrasound indentation.

    Science.gov (United States)

    Wang, Li-Ke; Huang, Yan-Ping; Tian, Lei; Kee, Chea-Su; Zheng, Yong-Ping

    2016-09-01

    Biomechanical properties are potential information for the diagnosis of corneal pathologies. An ultrasound indentation probe consisting of a load cell and a miniature ultrasound transducer as indenter was developed to detect the force-indentation relationship of the cornea. The key idea was to utilize the ultrasound transducer to compress the cornea and to ultrasonically measure the corneal deformation with the eyeball overall displacement compensated. Twelve corneal silicone phantoms were fabricated with different stiffness for the validation of measurement with reference to an extension test. In addition, fifteen fresh porcine eyes were measured by the developed system in vitro. The tangent moduli of the corneal phantoms calculated using the ultrasound indentation data agreed well with the results from the tensile test of the corresponding phantom strips (R(2)=0.96). The mean tangent moduli of the porcine corneas measured by the proposed method were 0.089±0.026MPa at intraocular pressure (IOP) of 15mmHg and 0.220±0.053MPa at IOP of 30mmHg, respectively. The coefficient of variation (CV) and intraclass correlation coefficient (ICC) of tangent modulus were 14.4% and 0.765 at 15mmHg, and 8.6% and 0.870 at 30mmHg, respectively. The preliminary study showed that ultrasound indentation could be applied to the measurement of corneal tangent modulus with good repeatability and improved measurement accuracy compared to conventional surface displacement-based measurement method. The ultrasound indentation can be a potential tool for the corneal biomechanical properties measurement in vivo. PMID:27262352

  5. The theory and art of corneal cross-linking

    Directory of Open Access Journals (Sweden)

    Rebecca McQuaid

    2013-01-01

    Full Text Available Before the discovery of corneal cross-linking (CXL, patients with keratoconus would have had to undergo corneal transplantation, or wear rigid gas permeable lenses (RGPs that would temporarily flatten the cone, thereby improving the vision. The RGP contact lens (CL would not however alter the corneal stability and if the keratoconus was progressive, the continued steepening of the cone would occur under the RGP CL. To date, the Siena Eye has been the largest study to investigate long term effects of standard CXL. Three hundred and sixty-three eyes were treated and monitored over 4 years, producing reliable long-term results proving long-term stability of the cornea by halting the progression of keratoconus, and proving the safety of the procedure. Traditionally, CXL requires epithelial removal prior to corneal soakage of a dextran-based 0.1% riboflavin solution, followed by exposure of ultraviolet-A (UV-A light for 30 min with an intensity of 3 mW/cm2. A series of in vitro investigations on human and porcine corneas examined the best treatment parameters for standard CXL, such as riboflavin concentration, intensity, wavelength of UV-A light, and duration of treatment. Photochemically, CXL is achieved by the generation of chemical bonds within the corneal stroma through localized photopolymerization, strengthening the cornea whilst minimizing exposure to the surrounding structures of the eye. In vitro studies have shown that CXL has an effect on the biomechanical properties of the cornea, with an increased corneal rigidity of approximately 70%. This is a result of the creation of new chemical bonds within the stroma.

  6. The application of excimer lasers for corneal sculpturing

    International Nuclear Information System (INIS)

    Of the broad selection of lasers available for surgery, the argon fluoride excimer laser offers a set of attributes that make it uniquely suited for the removal of corneal tissue. With ultraviolet radiation at 193mm, the energy of an individual photon (6.3 electron volts) is sufficient to break bonds in protein molecules without generating molecular vibration (heat). A single laser pulse is capable of removing 0.25 microns of corneal tissue over a well defined area 80 mm2 in extent. This excision with a lateral precision to a fraction of a micron causes no discernible damage to neighboring cells. The smooth surface left after the tissue is removed promotes a quick and predictable regrowth of the epithelium. The penetration of radiation into the underlying tissue is the order of a micron so there is no potential harm to the lens or retinal tissue. Insignificant mutagenesis or unscheduled DNA synthesis has been detected as a result of tissue irradiation at this wavelength. In the past few years major progress has been made towards developing ophthalmic procedures which utilize the unique properties of this laser. To date there are FDA IDE's (Investigational Device Exemptions) for the following procedures: Photorefractive Keratectomy (PRK) or corneal reshaping for correcting near-sightedness, far-sightedness and astigmatism without the need for eye glasses, contact lenses or conventional refractive surgery (Radial Keratotomy); Partial Excimer Trabeculectomy for relieving the pressure build-up caused by glaucoma; T-Excisons for reducing astigmatism; Myopic Keratomileusis (MKM) for the refractive correction of severe myopia; superficial Keratectomy (corneal smoothing) for treating various corneal scars, dystrophies, recurrent corneal erosion etc. In this paper the fundamentals of beam tissue interaction at 193nm will be discussed

  7. Traumatic Wound Dehiscence following Corneal Transplantation

    Directory of Open Access Journals (Sweden)

    Mohammad-Reza Jafarinasab

    2012-01-01

    Full Text Available Purpose: To investigate the incidence, mechanisms, characteristics, and visual outcomes of traumatic wound dehiscence following keratoplasty. Methods: Medical records of 32 consecutive patients with traumatic globe rupture following keratoplasty who had been treated at our center from 2001 to 2009 were retrospectively reviewed. Results: The study population consisted of 32 eyes of 32 patients including 25 men and 7 women with history of corneal transplantation who had sustained eye trauma leading to globe rupture. Mean patient age was 38.1 (range, 8 to 87 years and median interval between keratoplasty and the traumatic event was 9 months (range, 30 days to 20 years. Associated anterior segment findings included iris prolapse in 71.9%, lens extrusion in 34.4%, and hyphema in 40.6% of eyes. Posterior segment complications included vitreous prolapse (56%, vitreous hemorrhage (28% and retinal detachment (18%. Eyes which had undergone deep anterior lamellar keratoplasty (DALK; 5 cases, 15.6% tended to have less severe presentation and better final visual acuity. There was no correlation between the time interval from keratoplasty to the traumatic event, and final visual outcomes. Conclusion: The host-graft interface demonstrates decreased stability long after surgery and the visual prognosis of traumatic wound dehiscence is poor in many cases. An intact Descemet′s membrane in DALK may mitigate the severity of ocular injuries, but even in these cases, the visual outcome of globe rupture is not good and prevention of ocular trauma should be emphasized to all patients undergoing any kind of keratoplasty.

  8. Minocycline Inhibits Alkali Burn-Induced Corneal Neovascularization in Mice

    OpenAIRE

    Ou Xiao; Zhao-lian Xie; Bin-wu Lin; Xiao-fang Yin; Rong-biao Pi; Shi-you Zhou

    2012-01-01

    The purpose of this study was to investigate the effects of minocycline on alkali burn-induced corneal neovascularization (CNV). A total of 105 mice treated with alkali burns were randomly divided into three groups to receive intraperitoneal injections of either phosphate buffered saline (PBS) or minocycline twice a day (60 mg/kg or 30 mg/kg) for 14 consecutive days. The area of CNV and corneal epithelial defects was measured on day 4, 7, 10, and14 after alkali burns. On day 14, a histopathol...

  9. A circum-corneal conjunctival nevus in a child

    DEFF Research Database (Denmark)

    Svahn, T.F.; Heegaard, Steffen; Prause, Jan Ulrik; Toft, Peter

    2012-01-01

    An amelanotic, circum-corneal nevus in a 2-year-old child is described. The nevus presented at birth as a red spot in the nasal conjunctiva that subsequently enlarged to completely encircle the cornea. The tumour was partially removed three times, but at the age of 6 years, the nevus still covers...... the entire limbal region. The case illustrates that circum-corneal redness in a child may be caused by a nevus and that a conjunctival limbal nevus in a child tend to recur after incomplete excision....

  10. Multi-gene targeted antiangiogenic therapies for experimental corneal neovascularization

    OpenAIRE

    Chen, Peng; Yin, Hongmei; Wang, Yao; Mi, Jing; He, Wenxiao; Xie, Lixin; Wang, Yiqiang

    2010-01-01

    Purpose To determine the effectiveness of multigene-based anti-angiogenic gene therapies for experimental murine corneal neovascularization (corneal NV). Methods Recombinant retroviral vectors encoding murine endostatin (mEndo), murine-soluble vascular endothelial growth factor receptor-2 (msFlk-1), or murine-soluble Tie2 (msTie2) were constructed and packaged in PT67 cells. Viral titers were determined by infection of NIH3T3 cells. Expressions of mEndo, msFlk-1, and msTie2 were confirmed by ...

  11. Hypoxia preconditioning protects corneal stromal cells against induced apoptosis

    OpenAIRE

    Xing, Dongmei; Sun, Xingcai; Li, Jinhua; CUI, MIAO; Tan-Allen, Kah; Bonanno, Joseph A

    2005-01-01

    The purpose of this study, was to determine whether hypoxia preconditioning can protect corneal stromal cells from UV stress and cytokine mediated apoptosis. Two models were implemented. First, primary cultured bovine corneal fibroblasts were preconditioned with 0.5–1.5% O2 for 4 hr and stressed with UV-irradiation or stimulation of Fas receptor. Second, bovine eyes were preconditioned with 0.5% O2 for 4 hr and stressed by epithelial scraping to induce anterior keratocyte apoptosis. Cell fate...

  12. Bacterial corneal ulcer associated with common variable immune deficiency.

    Science.gov (United States)

    Tsui, Edmund; Deng, Jie; Siedlecki, Andrew N; Zegans, Michael E

    2016-12-01

    Common variable immune deficiency (CVID) is one of the most commonly diagnosed primary immunodeficiencies. Generally, patients have a history of recurrent sinopulmonary infections, hypogammaglobulinemia of two or more immunoglobulin isotypes, and impaired functional antibody responses. Reports of corneal involvement associated with CVID are limited. We describe a case of corneal ulceration associated with methicillin-resistant Staphylococcus aureus in a patient with CVID that developed while on monthly intravenous immunoglobulin infusions and in which there were no common risk factors for bacterial keratitis, such as prior history of ocular surface disease, trichiasis, trauma, or contact lens wear. PMID:27491761

  13. Noninvasive spectroscopic diagnosis of superficial ocular lesions and corneal infections

    Energy Technology Data Exchange (ETDEWEB)

    Mourant, J.R.; Bigio, I.J.; Johnson, T.; Shimada, T. [Los Alamos National Lab., NM (United States); Gritz, D.C.; Storey-Held, K. [Texas Univ. Health Science Center, San Antonio, TX (United States). Dept. of Ophthalmology

    1994-02-01

    The potential of a rapid noninvasive diagnostic system to detect tissue abnormalities on the surface of the eye has been investigated. The optical scatter signal from lesions and normal areas on the conjunctival sclera of the human eye were measured in vivo. It is possible to distinguish nonpigmented pingueculas from other lesions. The ability of the system to detect malignancies could not be tested because none of the measured and biopsied lesions were malignant. Optical scatter and fluorescence spectra of bacterial and fungal suspensions, and corneal irritations were also collected. Both scattering and fluorescence show potential for diagnosing corneal infections.

  14. Quantifying the effect of milli-molar glucose concentration on thickness of rabbit cornea with optical coherence tomography

    Science.gov (United States)

    Ghosn, Mohamad G.; Leba, Michael; Vijayananda, Astha; Ansari, Rafat R.; Larin, Kirill V.

    2009-02-01

    The cornea contributes about 65% of the eye's ability to refract light. Thus, any fluctuation in corneal thickness can cause noticeable changes in vision. The presence of glucose molecules induces a driving force for water to leave the collagen fibrils in the cornea due to the concentration gradient created, thus changing its thickness. In this study, the effect of various milli-molar glucose concentrations on corneal thickness was explored using Optical Coherence Tomography. Whole rabbit eyes were placed in a specially designed dish while immersed in saline to ensure proper hydration of the eye. The cornea was imaged for 10 minutes. In 30 minute increments, a higher concentration of glucose was added, bringing the overall glucose concentration to 10, 15, 20, 25, and 30 mM. The thickness of the cornea was measured every 2 minutes. Ultimately, an inverse relationship was observed, indicating that the increase in glucose concentration yielded a decrease in the corneal thickness. From three separate experiments, the cornea experienced 8 +/- 1, 27 +/- 1, 44 +/- 3, 58 +/- 3, and 64 +/- 3 μm decrease in thickness from its starting value while exposed to 10, 15, 20, 25, and 30 mM solutions of glucose, respectively. This relationship provides insight on the physiological changes of the cornea as a result of different glucose concentrations. This could potentially be useful in monitoring blood-glucose levels through the eye.

  15. Therapeutic effect and safety of accelarated transepithelial riboflavin-ultraviolet corneal collagen crosslinking for keratoconus%快速跨上皮核黄素-紫外光角膜胶原交联治疗圆锥角膜的临床疗效和安全性评价

    Institute of Scientific and Technical Information of China (English)

    张晶; 郑燕; 刘倩; 王玥; 李颖; 张秋露; 徐雯; 周跃华

    2016-01-01

    Background Researches showed that classic corneal collagen crosslinking (CXL) can effectively control the progression of keratoconus and corneal ectasia,but its adverse responses and complications are common due to the de-epithelial procedure.A transepithelial riboflavin-ultraviolet CXL surgery has applied in ophthalmology,but its effectiveness and safety evaluation is less.Objective This study was to evaluate the effectiveness and safety of rapid transepithelial riboflavin-ultraviolet CXL for keratoconus.Methods A prospective self-controlled study was designed.Forty-six eyes of 28 keratoconus patients scheduled to receive the rapid transepithelial riboflavin-ultraviolet CXL in Beijing Tongren Hospital from March to October in 2014 under the approval of this hospital and informed consent with a follow-up duration for one year.The spherical equivalent (SE) , astigmatic power, central corneal thickness (CCT), endothelial cell count, corneal topography parameters, the parameters from the anterior segment optical coherence tomography (AS-OCT) and corneal biomechanical parameters were examined before surgery and 1 week, 1 month,3 months,6 months and 12 months after surgery,and the results were compared among different time points to assess the effectiveness of transepithelial riboflavin-ultraviolet CXL for keratoconus.The postoperative irritation symptoms and adverse response were observed to evaluate the safety of surgery.Results No intraoperative complication and serious adverse postoperative infection were found in all the operated eyes.Slight irritation symptoms occurred in operated eyes 1 day after surgery and disappeared 3 days after surgery.A little reducing was seen in the spherical equivalent 1 month later, without significant difference among various time points (F =0.722, P =0.614).However, a significant reducing was found in astigmatic power in 12 months after surgery compared with before surgery (t =3.242,P =0.004).No considerably differences were seen in

  16. Effects of Silicone Hydrogel Contact Lens Application on Corneal High-order Aberration and Visual Guality in Patients with Corneal Opacities

    OpenAIRE

    Sevda Aydın Kurna; Sibel Aksoy; Tomris Şengör; Ayşe Sönmez

    2012-01-01

    Pur po se: Evaluation of the corneal high-order aberrations and visual quality changes after application of silicone hydrogel contact lenses in patients with corneal opacities due to various etiologies. Ma te ri al and Met hod: Fifteen eyes of 13 patients with corneal opacities were included in the study. During the ophthalmologic examination before and after contact lens application, visual acuity was measured with Snellen acuity chart and contrast sensitivity - with Bailey-Lowie Ch...

  17. Corneal astigmatism change and wavefront aberration evaluation after cataract surgery: "Single" versus "paired opposite" clear corneal incisions

    Directory of Open Access Journals (Sweden)

    Hasan Razmjoo

    2014-01-01

    Full Text Available Background: Correcting the pre-existing astigmatism is an optimal goal in cataract surgery. The aim of this study is to compare the astigmatic correcting effect of a single regular 3.2 mm clear corneal incision (CCI with paired opposite CCI in cataract patients and effect of these incisions on optical aberrations using the wavefront quantitative analysis. Materials and Methods: This was a randomized controlled trial study undertaken in an ophthalmology referral center on 50 patients planned for cataract surgery who were randomized to either single 3.2 mm CCI or paired opposite CCI group. Post-operative evaluation was performed at 12 weeks and included refraction, keratometery, corneal topography and wavefront analysis. Corneal astigmatism and post-operative values were compared in two groups. Results: The mean pre-operative corneal astigmatism was 2.58 ± 1.03 D in the single incision group and 2.70 ± 0.94 D in the paired opposite incisions group. After 12 weeks of surgery, the corneal astigmatism was reached to 2.15 ± 0.82 D in single incision group and 1.63 ± 1.21 in the paired opposite incisions group. There was a statistically significant difference in two arms of treatment regarding to surgically induced astigmatism after 3 months. The mean post-operative total and higher order aberrations and values were not significantly different in two groups. Conclusion: The results of our study showed that paired opposite incisions is an effective procedure for reducing pre-existing corneal astigmatism in cataract surgery. Paired incisions did not show any beneficial effect regarding wavefront aberrations compared with conventional single incision method.

  18. RTVue傅里叶光学相干断层扫描仪测量角膜参数的重复性和准确性评价%Repeatability and accuracy of corneal parameters measured by RTVue Fourier-domain optical coherence topography

    Institute of Scientific and Technical Information of China (English)

    华焱军; 黄锦海; 潘超; 王勤美

    2013-01-01

    膜地形图仪略大;RTVue FD-OCT获得的Rposterior/Ranterior比Gullstrand模型眼小,可能为建立更准确的标准化模型眼提供依据.%Background Corneal parameters (such as curvature,thickness,etc) are essential to the diagnosis of corneal related diseases,contact lenses fitting and corneal refractive surgery.Objective The aim of this study was to assess the repeatability and accuracy of corneal parameters obtained by RTVue Fourier-domain optical coherence topography (FD-OCT).Methods In this prospective study,77 eyes of 43 subjects with the refraction from-1.25 D to-10.00 D and astigmatism <2 D were enrolled in keratorefractive surgery center,Eye Hospital of Wenzhou Medical College.The anterior and posterior corneal curvature in 3 mm central zone (Ranterior and Rposterior),the ratio of posterior and anterior curvature (Rposterior/Ranterior),corneal central thickness (CCT),total corneal power(Knet),the simulated corneal power (Sim K),the anterior and posterior corneal power (Kanterior,Kposterior)were measured by FD-OCT.Corneal power (Km) was obtained by Topolyzer topography based on Placido ring.Three consecutive scans were acquired in every tested eye.Repeatability of FD-OCT measurement was assessed using the coefficient of variation CV),Cronbach Alpha and intra-class correlation coefficient (ICC).Repeated measure ANOVA was used to analyze the differences among SimK,Knet and Km.Pearson correlation analysis was used to analysis the correlation between SimK and K Knet and Km,SimK and Km.The agreement between Sim K and K Knet and Km,SimK and Km was assessed by Bland-Altman plots analysis.All the subjects understood the purpose of this investigation and written informed consent was obtained prior to the medical examination.Results The Ranterior,Rposterior,Rposterior/Ranterior,Kanterior,Kposterior,Sim K,Knet and CCT were (7.691 ±0.302) mm,(6.532±0.276) mm,0.849±0.014,(48.97±1.92)D,(-6.13±0.26)D,(43.95±1.72) D,(42.95±1.68) D and (545.20± 35.04) μm,respectively.The CV of all

  19. Analysis of human transforming growth factor β-induced gene mutation in corneal dystrophy

    Institute of Scientific and Technical Information of China (English)

    李杨; 孙旭光; 任慧媛; 董冰; 王智群; 孙秀英

    2004-01-01

    Background Corneal dystrophy is a group of inherited blinding diseases of the cornea. This study was to identify the mutations of the keratoepithelin (KE) gene for proper diagnosis of corneal dystrophy. Methods Three families with corneal dystrophy were analysed. Thirteen individuals at risk for corneal dystrophy in family A, the proband and her son in family B, and the proband in family C were examined after their blood samples were obtained. Mutation screening of human transforming growth factor β-induced gene (BIGH3 gene) was performed. Results Five individuals in family A were found by clinical evaluation to be affected with granular corneal dystrophy and carried the BIGH3 mutation W555R. However, both probands in families B and C, also diagnosed with granular corneal dystrophy, harboured the BIGH3 mutation R124H. Conclusion Molecular genetic analysis can improve accurate diagnosis of corneal dystrophy.

  20. Corneal Biomechanical and Anterior Chamber Parameters Variations after 1-year of Transepithelial Corneal Collagen Cross-linking in Eyes of Children with Keratoconus

    Science.gov (United States)

    Salman, Abdelrahman Gaber

    2016-01-01

    Aim: To assess the changes in corneal hysteresis (CH) and corneal resistance factor (CRF) 1-year following transepithelial corneal collagen cross-linking (CXL) treatment in eyes of children with keratoconus. Methods: This case series was conducted in 22 eyes of 22 children. Children aged 0.05). Conclusion: Transepithelial CXL in keratoconus in pediatric age group seems to have good stability in corneal biomechanical parameters after 1-year. Further studies with a larger sample and better study design are recommended to confirm our findings. PMID:26957852

  1. Changes of thickness of retinal nerve fiber layer and central fovea of macula in children with ametropic amblyopia%屈光不正性弱视儿童视网膜神经纤维层和黄斑中心凹厚度的变化

    Institute of Scientific and Technical Information of China (English)

    金守梅; 冯运红; 谢静; 郑小媚; 陈兆升; 许锦芳

    2015-01-01

    Objective To compare the thickness of retinal nerve fiber layer (RNFL) and central fovea of macula in children with ametropic amblyopia. Methods A total of 25 children (50 eyes) with ametropic amblyopia and 24 normal children (48 eyes) were enrolled. Thickness of RNFL and central fovea of macula of all subjects were measured by the Optical Coherence Tomography and compared and analyzed. Results The average thickness of the RNFL of the ametropic amblyopia group 121.32±8.06μm was significantly higher than that of the normal group 104.63±6.24μm, 0.05. The average thicknesses of the retinal nerve fiber layer had a negative correlation with the axis in normal eyes,=-0.42, 0.05,而正常组患者的视网膜神经纤维层平均厚度与眼轴呈明显相关,r=-0.42,P<0.05。结论屈光不正性弱视可影响患者的视网膜神经纤维层厚度。

  2. Corneal biomechanical changes following toric soft contact lens wear

    Directory of Open Access Journals (Sweden)

    Somayeh Radaie-Moghadam

    2016-01-01

    Conclusion: CH and CRF decreased significantly one month after fitting toric soft contact lenses while CCT and K mean did not change significantly. Corneal biomechanical parameters may alter with toric soft contact lens use and such changes may have implications with long-term use such lenses.

  3. The Impact of Pterygium Excision on Corneal Astigmatism

    International Nuclear Information System (INIS)

    Objective: To compare the corneal astigmatism before and after the excision of pterygium and also to determine the correlation of pterygium size with the postoperative corneal astigmatism. Study Design: Cross-sectional interventional study. Place and Duration of Study: Eye Department, Combined Military Hospital, Abbottabad, from May 2011 to March 2012. Methodology: Thirty patients underwent pterygium excision. Pre-operatively Snellen visual acuity, manifest refraction and slit lamp examination was done. The size of the pterygium was recorded in mm by projecting a horizontal slit lamp beam from the limbus to the apex. All the pterygium were equal to or greater than 2.5 mm. Keratometry was performed with an automated keratometer. Keratometric data was recorded pre-operatively and at 28 days postoperatively. Wilcoxon signed rank test was used for comparing the pre-operative and the postoperative corneal astigmatism. Spearman's rank order was calculated to observe correlation of pterygium size with the postoperative astigmatism. Results: The median (mean rank) pre-operative astigmatism of 2.25 (15.50) reduced to a median (mean rank) postoperative astigmatism of 1.30 (14.96). This decrease in the postoperative astigmatism was statistically significant (p < 0.001). There was a statistically non-significant correlation between the postoperative astigmatism and the pterygium size (rs = -0.29, p = 0.12). Conclusion: Pterygium excision caused significant reduction in corneal astigmatism. (author)

  4. Role of matrix metalloproteinases in recurrent corneal melting

    Czech Academy of Sciences Publication Activity Database

    Brejchová, K.; Lisková, P.; Čejková, Jitka; Jirsová, K.

    2010-01-01

    Roč. 90, č. 5 (2010), s. 583-590. ISSN 0014-4835 Institutional research plan: CEZ:AV0Z50390512 Keywords : corneal melting * extracellular matrix degradation * matrix metalloproteinases Subject RIV: FF - HEENT, Dentistry Impact factor: 2.817, year: 2010

  5. Viability of human corneal keratocytes during organ culture

    DEFF Research Database (Denmark)

    Møller-Pedersen, T; Møller, H J

    1996-01-01

    The viability of human corneal keratocytes was assessed during four weeks of 'closed system' organ culture at 31 degrees C. After 28 days of culturing, the entire keratocyte population was still alive and viable because all cells incorporated uridine; a parameter for RNA-synthesis. During the first...

  6. Corneal manifestations of selected systemic diseases: A review

    Directory of Open Access Journals (Sweden)

    Wayne D.H. Gillan

    2015-03-01

    Full Text Available The corneal manifestations of several selected systemic diseases are reviewed. Metabolic, immunologic and inflammatory and infectious diseases are included. A brief overview of each disease and how it manifests in the cornea is discussed. The importance of conducting a slit-lamp examination on every patient is emphasised.

  7. Implantation epithelial iris cyst following the perforating corneal injury

    Directory of Open Access Journals (Sweden)

    Jovanović Miloš

    2006-01-01

    Full Text Available The objective of this case report was to present the development of implantation cyst following the perforating corneal injury, the problems related to the treatment, including total surgical excision of the cyst, the secondary cataract extraction, iridoplasty and the artificial intraocular lens reposition. A patient first presented with perforating corneal injury inflicted by a piece of wood, with the iris prolapse. Primary wound management, reposition of prolapsed iris and corneal sutures were performed four days after the injury. Eight months later, the patient was rehospitalized due to an implantation iris cyst and traumatic cataract. The cyst was excised, the extracapsular cataract extraction was done and the anterior chamber lens was implanted. Postoperative visual acuity was normal. Three years later, the patient presented for a follow-up examination, with the cyst filled up again, occupying two thirds of the anterior chamber. This time, the cyst was completely excised, all fibrous remnants of the secondary cataract were removed, and the iridoplasty was necessary due to large iris coloboma. Reposition of the anterior chamber lens was carried out. Histological examination revealed an implantation iris cyst covered by multilayered squamous epithelium. Normal visual acuity was achieved. The patient has been followed-up for six months uneventfully. Management of perforating corneal wound with iris prolapse may lead to development of an implantation iris cyst. Puncture of the cyst as well as incomplete excision will not solve the problem. Complete surgical removal of the iris cyst is the treatment of choice.

  8. The response of healing corneal epithelium to grooved polymer surfaces.

    NARCIS (Netherlands)

    Evans, M.D.; McFarland, G.A.; Taylor, S.; Walboomers, X.F.

    2005-01-01

    Corneal epithelial wounds heal rapidly by the inwards growth of tissue with a contracting wound front. A synthetic polymer lens to correct refractive error (an implantable contact lens) could be incorporated into the cornea using this wound healing process. Topographical cues on the polymer surface

  9. Posterior corneal curvature changes following Refractive Small Incision Lenticule Extraction

    Directory of Open Access Journals (Sweden)

    Ganesh S

    2015-07-01

    Full Text Available Sri Ganesh, Utsav Patel, Sheetal Brar Phaco and Refractive Surgery Department, Nethradhama Superspeciality Eye Hospital, Bengaluru, Karnataka, India Purpose: To compare the posterior corneal curvature changes, in terms of corneal power and asphercity, following Refractive Small Incision Lenticule Extraction (ReLEx SMILE procedure for low, moderate, and high myopia.Methods: This retrospective, non randomized, comparative, interventional trial; included 52 eyes of 26 patients, divided in three groups: low myopia (myopia ≤3 D [diopters] spherical equivalent [SE], moderate myopia (myopia >3 D and <6 D SE, and high myopia (myopia ≥6 D SE. All patients were treated for myopia and myopic astigmatism using ReLEx SMILE. The eyes were examined pre-operatively and 3 months post-operatively using SCHWIND SIRIUS, a three-dimensional rotating Scheimpflug camera with a Placido disc topographer to assess corneal changes with regard to keratometric power and asphericity of the cornea.Results: A statistically significant increase in mean keratometric power in the 3, 5, and 7 mm zones of the posterior corneal surface compared with its pre-ReLEx SMILE value was detected after 3 months in the moderate myopia group (pre-operative [pre-op] -6.14±0.23, post-operative [post-op] -6.29±0.22, P<0.001 and high myopia group (pre-op -6.19±0.16, post-op -6.4±0.18, P<0.001, but there was no significant change in keratometric power of the posterior surface in the low myopia group (pre-op -5.87±0.17, post-op -6.06±0.29, P=0.143. Asphericity (Q-value of the posterior surface changed significantly (P<0.001 after ReLEx SMILE in the moderate myopia group in the 3, 5, and 7 mm zones, and in the high myopia group in the 3 and 7 mm zones; but there was no significant change in the Q-value in the low myopia group in all three zones (pre-op 0.23±0.43, post-op -0.40±0.71, P=0.170, and in the high myopia group in the 5 mm zone (P=0.228.Conclusion: ReLEx SMILE causes significant

  10. Corneal collagen crosslinking in keratoconus and other eye disease

    Institute of Scientific and Technical Information of China (English)

    Adel; Alhayek; Pei-Rong; Lu

    2015-01-01

    Keratoconus is a condition characterized by biomechanical instability of the cornea, presenting in a progressive, asymmetric and bilateral way. Corneal collagen crosslinking(CXL) with riboflavin and Ultraviolet-A(UVA) is a new technique of corneal tissue strengthening that combines the use of riboflavin as a photo sensitizer and UVA irradiation. Studies showed that CXL was effective in halting the progression of keratoconus over a period of up to four years. The published studies also revealed a reduction of max K readings by more than 2 D, while the postoperative spherical equivalent(SEQ) was reduced by an average of more than 1 D and refractive cylinder decreased by about1 D. The major indication for the use of CXL is to inhibit the progression of corneal ecstasies, such as keratoconus and pellucid marginal degeneration. CXL may also be effective in the treatment and prophylaxis of iatrogenic keratectasia, resulting from excessively aggressive photo ablation. This treatment has been used to treat infectious corneal ulcers with apparent favorable results. Most recent studies demonstrate the beneficial impact of CXL for iatrogenic ecstasies, pellucid marginal degeneration, infectious keratitis, bullous keratopathy and ulcerative keratitis. Several long-term and short-term complications of CXL have been studied and documented. The possibility of a secondary infection after the procedure exists because the patient is subject to epithelial debridement and the application of a soft contact lens. Formation of temporary corneal haze,permanent scars, endothelial damage, treatment failure,sterile infiltrates, bullous keratopathy and herpes reactivation are the other reported complications of this procedure.

  11. The effect of riboflavin/UVA collagen cross-linking therapy on the structure and hydrodynamic behaviour of the ungulate and rabbit corneal stroma.

    Directory of Open Access Journals (Sweden)

    Sally Hayes

    Full Text Available PURPOSE: To examine the effect of riboflavin/UVA corneal crosslinking on stromal ultrastructure and hydrodynamic behaviour. METHODS: One hundred and seventeen enucleated ungulate eyes (112 pig and 5 sheep and 3 pairs of rabbit eyes, with corneal epithelium removed, were divided into four treatment groups: Group 1 (28 pig, 2 sheep and 3 rabbits were untreated; Group 2 (24 pig were exposed to UVA light (3.04 mW/cm(2 for 30 minutes and Group 3 (29 pig and Group 4 (31 pig, 3 sheep and 3 rabbits had riboflavin eye drops applied to the corneal surface every 5 minutes for 35 minutes. Five minutes after the initial riboflavin instillation, the corneas in Group 4 experienced a 30 minute exposure to UVA light (3.04 mW/cm(2. X-ray scattering was used to obtain measurements of collagen interfibrillar spacing, spatial order, fibril diameter, D-periodicity and intermolecular spacing throughout the whole tissue thickness and as a function of tissue depth in the treated and untreated corneas. The effect of each treatment on the hydrodynamic behaviour of the cornea (its ability to swell in saline solution and its resistance to enzymatic digestion were assessed using in vitro laboratory techniques. RESULTS: Corneal thickness decreased significantly following riboflavin application (p<0.01 and also to a lesser extent after UVA exposure (p<0.05. With the exception of the spatial order factor, which was higher in Group 4 than Group 1 (p<0.01, all other measured collagen parameters were unaltered by cross-linking, even within the most anterior 300 microns of the cornea. The cross-linking treatment had no effect on the hydrodynamic behaviour of the cornea but did cause a significant increase in its resistance to enzymatic digestion. CONCLUSIONS: It seems likely that cross-links formed during riboflavin/UVA therapy occur predominantly at the collagen fibril surface and in the protein network surrounding the collagen.

  12. Laser differential confocal lens thickness measurement

    International Nuclear Information System (INIS)

    Based on the property that the absolute zero of an axial intensity curve exactly corresponds to the focus of the objective in a differential confocal system (DCS), a new laser differential confocal lens thickness measurement is proposed to achieve the high-precision non-contact measurement of lens thickness. The proposed approach uses the absolute zero of DCS axial response curve to precisely identify the vertexes of the test lens, obtains the central optical thickness of the test lens, and then uses the radius of curvature and refractive index of the test lens and the ray tracing facet iterative calculation to obtain the central geometrical thickness of the test lens. The theoretical analyses and preliminary experiments indicate that the measurement accuracy is better than 0.03%. (paper)

  13. Evaluation of intrastromal corneal ring segments for treatment of post-LASIK ectasia patients with a mechanical implantation technique

    Directory of Open Access Journals (Sweden)

    Zeki Tunc

    2011-01-01

    Full Text Available Aim: To evaluate the clinical outcomes of Keraring segment implantation in patients with post- laser-assisted in situ keratomileusis (LASIK ectasia, using a mechanical implantation technique. Materials and Methods: Twelve eyes of 10 patients with post-LASIK ectasia were enrolled. Intracorneal ring segments (ICRS were implanted after dissection of the tunnel using Tunc′s specially designed dissector under suction. A complete ophthalmic examination was performed, including uncorrected distance visual acuity (UDVA, corrected distance visual acuity (CDVA, spherical equivalent, keratometric (K readings, inferosuperior asymmetry index (ISAI, and ultrasound pachymetry. All 3, 6, and 12-month follow-ups were completed, and statistical analysis was performed. Results: The mean preoperative UDVA for all eyes was 1.28 ± 0.59 logMAR. At 12 months, the mean UDVA was 0.36 ± 0.19 logarithm of the Minimum Angle of Resolution (logMAR (P=0.002, and the mean preoperative CDVA was 0.58 ± 0.3 logMAR, which improved to 0.15 ± 0.12 (P=0.002 at 1 year. There was a significant reduction in cylindrical refractive and spherical equivalent refractive error from -5.29 ± 2.47 diopters (D and -5.54 ± 5.04 D preoperatively to -1.47 ± 0.71 D and -0.74 ± 1.07 D (P=0.001, P=0.002, respectively, at 1 year. In the same period, the mean K- readings improved from 47.93 ± 4.84 D to 40.87 ± 2.36 D (P=0.002, and the mean ISAI improved from 5.34 ± 3.05 to 2.37 ± 1.68 (P=0.003. No significant changes in mean central corneal thickness were observed postoperatively. There were no major complications during or after surgery. Conclusion: ICRS implantation using a unique mechanical dissection technique is a safe and effective treatment for post-LASIK ectasia. All parameters showed improvement at 1-year follow-up.

  14. Influence of HLA-A, HLA-B, and HLA-DR matching on rejection of random corneal grafts using corneal tissue for retrospective DNA HLA typing

    NARCIS (Netherlands)

    M.C. Bartels (Marjolijn); H.G. Otten; B.E. van Gelderen; A. van der Lelij (Allegonda)

    2001-01-01

    textabstractAIM: To establish if coincidental HLA-A, HLA-B, and HLA-DR tissue matching is associated with a reduced likelihood of corneal graft rejection. METHODS: Organ culture preserved random donor corneas were used for penetrating keratoplasty (PKP). Corneal tissue from all gra

  15. Anterior Lamina Cribrosa Surface Depth in Open-Angle Glaucoma: Relationship with the Position of the Central Retinal Vessel Trunk

    Science.gov (United States)

    Oh, Baek-Lok; Kim, Hyunjoong; Girard, Michaël J. A.; Mari, Jean Martial; Kim, Tae-Woo

    2016-01-01

    Purpose To determine the factors influencing the anterior lamina cribrosa (LC) surface depth (LCD) in patients with open-angle glaucoma (OAG), focusing on the association between LCD and the position of the central retinal vessel trunk (CRVT) at the anterior LC surface. Methods Optic nerve heads of 205 OAG eyes were scanned using swept-source optical coherence tomography (SS-OCT). After processing the images using adaptive compensation, the LCD was determined from 11 horizontal B-scan images that divided the optic disc vertically into 12 equal parts. Eyes were divided into two groups (central or peripheral) according to where the CRVT exits from the anterior LC surface. The influence of CRVT position on LCD was evaluated, taking into account age, gender, untreated intraocular pressure (IOP), IOP at optic-disc scanning, retinal nerve fiber layer (RNFL) thickness, visual-field mean deviation, central corneal thickness, and axial length. Results Patients in the peripheral CRVT group were younger and more myopic, and had a larger mean LCD and thinner global RNFL than those in the central CRVT group (all P≤0.023). On multivariate analysis, the peripheral CRVT location was significantly associated with a larger LCD (P = 0.002), together with the significant association of younger age (P<0.001), higher untreated IOP (P = 0.010), and thinner RNFL (P = 0.003) on the larger LCD. Conclusion In OAG, CRVT location was an independent factor influencing the LCD, together with age, untreated IOP, and global RNFL thickness. The data indicate that the CRVT may contribute to the resistance of the LC against deformation. A longitudinal prospective observation is required to clarify this relationship. PMID:27355646

  16. Hevin plays a pivotal role in corneal wound healing.

    Directory of Open Access Journals (Sweden)

    Shyam S Chaurasia

    Full Text Available BACKGROUND: Hevin is a matricellular protein involved in tissue repair and remodeling via interaction with the surrounding extracellular matrix (ECM proteins. In this study, we examined the functional role of hevin using a corneal stromal wound healing model achieved by an excimer laser-induced irregular phototherapeutic keratectomy (IrrPTK in hevin-null (hevin(-/- mice. We also investigated the effects of exogenous supplementation of recombinant human hevin (rhHevin to rescue the stromal cellular components damaged by the excimer laser. METHODOLOGY/PRINCIPAL FINDINGS: Wild type (WT and hevin (-/- mice were divided into three groups at 4 time points- 1, 2, 3 and 4 weeks. Group I served as naïve without any treatment. Group II received epithelial debridement and underwent IrrPTK using excimer laser. Group III received topical application of rhHevin after IrrPTK surgery for 3 days. Eyes were analyzed for corneal haze and matrix remodeling components using slit lamp biomicroscopy, in vivo confocal microscopy, light microscopy (LM, transmission electron microscopy (TEM, immunohistochemistry (IHC and western blotting (WB. IHC showed upregulation of hevin in IrrPTK-injured WT mice. Hevin (-/- mice developed corneal haze as early as 1-2 weeks post IrrPTK-treatment compared to the WT group, which peaked at 3-4 weeks. They also exhibited accumulation of inflammatory cells, fibrotic components of ECM proteins and vascularized corneas as seen by IHC and WB. LM and TEM showed activated keratocytes (myofibroblasts, inflammatory debris and vascular tissues in the stroma. Exogenous application of rhHevin for 3 days reinstated inflammatory index of the corneal stroma similar to WT mice. CONCLUSIONS/SIGNIFICANCE: Hevin is transiently expressed in the IrrPTK-injured corneas and loss of hevin predisposes them to aberrant wound healing. Hevin (-/- mice develop early corneal haze characterized by severe chronic inflammation and stromal fibrosis that can be rescued

  17. Minocycline inhibits alkali burn-induced corneal neovascularization in mice.

    Directory of Open Access Journals (Sweden)

    Ou Xiao

    Full Text Available The purpose of this study was to investigate the effects of minocycline on alkali burn-induced corneal neovascularization (CNV. A total of 105 mice treated with alkali burns were randomly divided into three groups to receive intraperitoneal injections of either phosphate buffered saline (PBS or minocycline twice a day (60 mg/kg or 30 mg/kg for 14 consecutive days. The area of CNV and corneal epithelial defects was measured on day 4, 7, 10, and14 after alkali burns. On day 14, a histopathological examination was performed to assess morphological change and the infiltration of polymorphonuclear neutrophils (PMNs. The mRNA expression levels of vascular endothelial growth factor (VEGF and its receptors (VEGFRs, basic fibroblast growth factor (bFGF, matrix metalloproteinases (MMPs, interleukin-1α, 1β, 6 (IL-1α, IL-1β, IL-6 were analyzed using real-time quantitative polymerase chain reaction. The expression of MMP-2 and MMP-9 proteins was determined by gelatin zymography. In addition, enzyme-linked immunosorbent assay was used to analyze the protein levels of VEGFR1, VEGFR2, IL-1β and IL-6. Minocycline at a dose of 60 mg/kg or 30 mg/kg significantly enhanced the recovery of the corneal epithelial defects more than PBS did. There were significant decreases of corneal neovascularization in the group of high-dosage minocycline compared with the control group at all checkpoints. On day 14, the infiltrated PMNs was reduced, and the mRNA expression of VEGFR1, VEGFR2, bFGF, IL-1β, IL-6, MMP-2, MMP-9, -13 as well as the protein expression of VEGFR2, MMP-2, -9, IL-1β, IL-6 in the corneas were down-regulated with the use of 60 mg/kg minocycline twice a day. Our results showed that the intraperitoneal injection of minocycline (60 mg/kg b.i.d. can significantly inhibit alkali burn-induced corneal neovascularization in mice, possibly by accelerating corneal wound healing and by reducing the production of angiogenic factors, inflammatory cytokines and MMPs.

  18. 单眼弱视儿童视网膜神经纤维层和黄斑中心凹厚度分析%Thickness of retinal nerve fiber layer and central fovea of macula in children with unilateral amblyopia

    Institute of Scientific and Technical Information of China (English)

    傅扬; 唐敏; 孙晓东; 许迅

    2012-01-01

    Objective To compare the thickness of peripapillary retinal nerve fiber layer ( RNFL) and central fovea of macula between amblyopic eyes and non-amblyopic eyes in children with unilateral amblyopia. Methods Twenty-three children with unilateral amblyopia were selected, the thickness of RNFL around optic disk ( superior, temporal, inferior and nasal quadrants) and mean thickness of RNFL were measured by optical coherence tomography ( OCT ) , the mean thickness of central fovea of 1 mm in diameter and the smallest thickness of cental fovea of macula were examined, and the differences between amblyopic eyes and non-amblyopic eyes were compared. Results The thickness of RNFL in the temporalquadrant in amblyopic eyes was smaller than that in non-amblyopic eyes (t = -4.671, P =0.000 1), while there was no significant difference in the thickness of RNFL in the superior, inferior or nasal quadrants and the mean thickness of RNFL between amblyopic eyes and non-amblyopic eyes (P >0.05) . There was no significant difference in the mean thickness of fovea of 1 mm in diameter between amblyopic eyes and non-amblyopic eyes (t = 0. 082 3, P = 0. 935 1) , while the smallest thickness in central fovea of macula in amblyopic eyes was smaller than that in non-amblyopic eyes (t = -2. 371 0, P = 0.026 9). Conclusion There exist differences in peripapillary RNFL and structure of macula between amblyopic eyes and non-amblyopic eyes in children with unilateral amblyopia.%目的 比较单眼弱视儿童弱视眼与非弱视眼的视盘周围神经纤维层(RNFL)和黄斑中心凹厚度的差异.方法 选取单眼弱视儿童23人,利用光学相干断层扫描(OCT)技术分别检测双眼视盘上方、颞侧、下方、鼻侧4个象限RNFL厚度及RNFL平均厚度,检测黄斑中心凹1 mm直径区域平均厚度和黄斑中心凹最小厚度,比较同一受检者弱视眼与非弱视眼的差异.结果 弱视眼视盘颞侧象限RNFL厚度小于非弱视眼(t=-4.671,P=0.000 1),而视盘

  19. Opposite Clear Corneal Incisions versus Steep Meridian Incision Phacoemulsification for Correction of Pre-existing Astigmatism

    Directory of Open Access Journals (Sweden)

    Mohammad Naim Aminifard

    2015-01-01

    Full Text Available Background: To compare the efficacy of adding an opposite clear corneal incision (OCCI on the steep meridian versus performing surgery on the steep meridian alone during phacoemulsification in reducing pre-existing corneal astigmatism in Alzahra ophthalmology center. Materials and Methods: This randomized clinical trial was performed on 40 eyes with corneal astigmatism undergoing phacoemulsification and divided randomly to two groups. In the first group 3.2 mm phacoemulsification incision was made on steep meridian and in the other group after the procedure was completed the surgeon made 3.2 mm incision opposite to the main incision. Patients were followed with refraction, keratometry at 1, 4, 12 weeks. Results: Mean corrected astigmatism was greater in opposite clear corneal incision group than steep meridian incision phacoemulsification group. No significant change occurred in amount of astigmatism in two groups. Conclusion: Opposite clear corneal incisions achieve an enhanced effect over single clear corneal incisions in treating preexisting astigmatism in cataract patients.

  20. Deformidade corneana em usuário de lente de contato portador de ceratocone: relato de caso Corneal warpage in contact lens wearer with keratoconus: a case report

    Directory of Open Access Journals (Sweden)

    César Lipener

    1999-12-01

    Full Text Available Introdução: Alterações topográficas podem ocorrer secundariamente ao uso de uso de lentes de contato duras ou gelatinosas. O termo "corneal warpage" é utilizado para denominar as deformidades corneanas causadas pelas lentes. O quadro topográfico da fase inicial do ceratocone pode ser muito parecido com o de um paciente com este quadro. Objetivo: Mostrar um paciente portador de ceratocone, usuário de lentes de contato rígida gás-permeável (RGP que desenvolveu quadro de "corneal warpage", diagnosticado e acompanhado por topografias e exames clínicos seriados. Relato de caso: O paciente é um engenheiro de 40 anos com diagnóstico de ceratocone bilateral há 12 anos, usando lentes RGP desde então. No primeiro exame em 5/95, a refração de OD foi impossível de se determinar e a ceratometria era maior que 60,00 D. Foi feita topografia, que se mostrou compatível com ceratocone, tendo sido adaptada uma lente Soper, com visão de 20/70. Após um ano, uma topografia de controle mostrou aumento da curvatura central e aplanamento da periferia inferior. O uso da lente foi suspenso e após 6 meses houve regressão das mudanças, tendo sido adaptadas novas lentes com melhor padrão e visão de 20/40. Discussão: O caso apresentado evidencia a ocorrência de deformidade corneana em um portador de ceratocone usuário de lente RGP. O autor discute a fisiopatologia e o diagnóstico clínico e topográfico do "corneal warpage", lembrando que a exemplo de pacientes normais, os pacientes com ceratocone podem apresentar estas alterações, que devem ser diferenciadas da própria evolução da doença.Introduction: Topographical alterations may occur as a secondary result of the use of hard or soft contact lenses. The expression corneal warpage is used to describe the corneal deformities caused by the lenses. Topographical map of initial keratoconus can be very similar to that of a patient with corneal warpage. Purpose: To describe a contact lens

  1. Indications for Corneal Transplantation at a Tertiary Referral Center in Tehran

    OpenAIRE

    Mohammad Zare; Mohammad-Ali Javadi; Bahram Einollahi; Alireza Baradaran-Rafii; Siamak Zarei Ghanavati; Mohammad-Reza Jamshidi Farsani; Parviz Mohammadi; Sepehr Feizi

    2010-01-01

    Purpose: To report the indications and techniques of corneal transplantation at a tertiary referral center in Tehran over a 3-year period. Methods: Records of patients who had undergone any kind of corneal transplantation at Labbafinejad Medical Center, Tehran, Iran from March 2004 to March 2007 were reviewed to determine the indications and types of corneal transplantation. Results: During this period, 776 eyes of 756 patients (including 504 male subjects) with mean age of 41.3±21.3 ...

  2. PHACOEMULSIFICATION AND SUTURELESS LARGE-INCISION MANUAL CATARACT EXTRACTION CHANGE CORNEAL SENSIBILITY

    OpenAIRE

    I Anom-Supradnya; W Jayanegara; I Sugiana; I Raka-Widiana

    2013-01-01

    Background: Cataract is the leading cause of blindness worldwide, with surgery as a definitive therapy. Incisions may damage the underlying tissue, including loss of corneal sensibility. The purpose of this study was to determine differences in corneal sensibility decreased in patients afterphacoemulsification and SLIMCE.Method: This study was a randomized clinical trial assessingchanges of corneal sensibility in immature senile cataract patients after phacoemulsification and SLIMCE at Sangla...

  3. Human limbal biopsy–derived stromal stem cells prevent corneal scarring

    OpenAIRE

    Basu, Sayan; Hertsenberg, Andrew J.; Funderburgh, Martha L.; Burrow, Michael K.; Mann, Mary M.; Du, Yiqin; Lathrop, Kira L.; Syed-Picard, Fatima N.; Adams, Sheila M.; Birk, David E.; Funderburgh, James L.

    2014-01-01

    Conventional allograft therapy for corneal scarring is widespread and successful, but donor tissue is not universally available, and some grafts fail owing to rejection and complications such as endothelial failure. We investigated direct treatment of corneal scarring using autologous stem cells, a therapy that, if successful, could reduce the need for corneal grafts. Mesenchymal cells were expanded from small superficial, clinically replicable limbal biopsies of human cadaveric corneo-sclera...

  4. Gelam honey potentiates ex vivo corneal keratocytes proliferation with desirable phenotype expression

    OpenAIRE

    Yusof, Alia Md; Abd Ghafar, Norzana; Kamarudin, Taty Anna; Hui, Chua Kien; Yusof, Yasmin Anum Mohd

    2016-01-01

    Background This study aimed to evaluate the effects of Gelam honey on corneal keratocytes proliferative capacity and phenotypic characterization via MTT assay, gene expression and immunocytochemistry. Methods Corneal keratocytes from New Zealand white rabbits were cultured in basal medium (BM) and serum enriched medium (BMS). Serial dilutions of Gelam honey (GH) were added to both media and cells were cultured until passage 1. MTT assay was performed on corneal keratocytes in both media to as...

  5. Change in Astigmatism After Temporal Clear Corneal Cataract Extraction in the Pediatric Population

    OpenAIRE

    Lam, Helene Y; Yen, Kimberly G

    2008-01-01

    Purpose: To evaluate the early postoperative change in astigmatism in pediatric patients having cataract extraction with intraocular lens implantation using sutured temporal clear corneal incision. Methods: A retrospective chart review was performed on all pediatric patients who underwent clear corneal cataract surgery with intraocular lens implantation between 12/01/2005 and 11/30/2006. Results: A total of 31 eyes of 22 patients who underwent temporal clear corneal cataract surgery and intra...

  6. Corneal-Based Surgical Presbyopic Therapies and Their Application in Pseudophakic Patients

    OpenAIRE

    Paley, Grace l.; Chuck, Roy S.; Tsai, Linda M.

    2016-01-01

    Purpose. The purpose of this review is to provide a summary of laser refractive surgery and corneal inlay approaches to treat presbyopia in patients after cataract surgery. Summary. The presbyopic population is growing rapidly along with increasing demands for spectacle independence. This review will focus on the corneal-based surgical options to address presbyopia including various types of corneal intrastromal inlays and laser ablation techniques to generate either a multifocal cornea (“Pre...

  7. Pseudomonas aeruginosa invasion of and multiplication within corneal epithelial cells in vitro.

    OpenAIRE

    Fleiszig, S M; Zaidi, T S; Pier, G.B. (G.B.)

    1995-01-01

    Pseudomonas aeruginosa is usually considered an extracellular pathogen. Using assays to determine intracellular survival in the presence of gentamicin, we have previously demonstrated that P. aeruginosa is able to invade corneal cells during infectious keratitis in mice. In vitro, P. aeruginosa was found to enter the following cells: human corneal cells removed by irrigation; epithelial cells in the cornea of rats, mice, and rabbits; and primary corneal epithelial cells cultured from rat and ...

  8. Risk Factors for Senile Corneal Arcus in Patients with Acute Myocardial Infarction

    OpenAIRE

    Moosavi, Mirnaghi; Sareshtedar, Ahmad; Zarei-Ghanavati, Siamak; Zarei-Ghanavati, Mehran; Ramezanfar, Nazanin

    2010-01-01

    Purpose To investigate the association between senile corneal arcus and atherosclerosis risk factors in patients with recent acute myocardial infarction. Methods In this cross sectional study, atherosclerosis risk factors including fasting blood sugar, total cholesterol and triglyceride levels were measured in 165 patients with recent (less than three months’ duration) acute myocardial infarction. Slitlamp examination was performed to detect corneal arcus. Associations between senile corneal ...

  9. Reconstruction of the corneal epithelium with induced marrow mesenchymal stem cells in rats

    OpenAIRE

    Jiang, Ting-Shuai; Cai, Li; Ji, Wei-Ying; Hui, Yan-Nian; Wang, Yu-Sheng; Hu, Dan; Zhu, Jie

    2010-01-01

    Purpose To explore the feasibility of bone marrow mesenchymal stem cells (MSCs) transdifferentiating into corneal epithelial cells in a limbal stem cell deficiency (LSCD) model in rats. Methods Rat MSCs were isolated and purified using a gradient isolation procedure. The cells were induced by rat corneal stromal cells (CSCs) in a transwell co-culture system. The induced MSCs were identified by immunofluorescence staining, flow cytometry, and scanning electron microscopy (SEM). A corneal LSCD ...

  10. Allergic Conjunctivitis Exacerbates Corneal Allograft Rejection by Activating Th1 and Th2 Alloimmune Responses

    OpenAIRE

    Niederkorn, Jerry Y.; Chen, Peter W.; Mellon, Jessamee; Stevens, Christina; Mayhew, Elizabeth

    2010-01-01

    Allergic conjunctivitis (AC) and airway hyperreactivity exacerbate corneal allograft rejection. Because AC and airway hyperreactivity are allergic diseases of mucosal tissues, we determined whether an allergic disease of a nonmucosal tissue would affect corneal allograft rejection and whether Th2 cells alone accounted for accelerated graft rejection in allergic mice. Hosts sensitized cutaneously with short ragweed pollen developed cutaneous immediate hypersensitivity but rejected corneal allo...

  11. Successful transplantation of in vitro expanded human corneal endothelial precursors to corneal endothelial surface using a nanocomposite sheet

    Directory of Open Access Journals (Sweden)

    Parikumar P

    2011-01-01

    Full Text Available Background: Though the transplantation of in vitro expanded human corneal endothelial precursors in animal models of endothelial damage by injecting into the anterior chamber has been reported, the practical difficulties of accomplishing such procedure in human patients have been a hurdle to clinical translation. Here we report the successful transplantation of in vitro expanded human corneal precursor cells to an animal eye using a transparent Nano-composite sheet and their engraftment.Materials and Methods: Human Corneal endothelial cells (HCEC were isolated from human cadaver eyes with informed consent and expanded in the lab using a sphere forming assay in a novel Thermoreversible Gelation Polymer (TGP for 26 days. HCEC obtained by sphere forming assay were seeded in a novel Nano-composite sheet, which was made of PNIPA-NC gels by in-situ, free-radical polymerization of NIPA monomer in the presence of exfoliated clay (synthetic hectorite “Laponite XLG” uniformly dispersed in aqueous media. After a further seven days in vitro culture of HCEC in the Nano-composite sheet, cells were harvested and transplanted on cadaver-bovine eyes (n=3. The cells were injected between the corneal endothelial layer and the Nano-composite sheet that had been placed prior to the injection in close proximity to the endothelial layer. After three hours, the transplanted Nano-composite sheets were removed from the bovine eyes and subjected to microscopic examination. The corneas were subjected to Histo-pathological studies along with controls. Results: HCEC formed sphere like colonies in TGP which expressed relevant markers as confirmed by RT-PCR. Microscopic studies of the Nanosheets and histopathological studies of the cornea of the Bull’s eye revealed that the HCEC got engrafted to the corneal endothelial layer of the bovine eyes with no remnant cells in the Nanosheet. Conclusion: Transplantation of in vitro expanded donor human corneal endothelial cells

  12. Phototoxic effects of 8-methoxypsoralen on rabbit corneal endothelium

    International Nuclear Information System (INIS)

    The phototoxic effects of 8-methoxypsoralen (8-MOP) were investigated using the rabbit corneal endothelium in organ culture. The corneas were divided into four groups: (a) irradiated with a mercury vapor lamp (emitting UVA and visible radiation) in the presence of 8-MOP (experimental), (b) irradiated without 8-MOP (control A), (c) incubated with 8-MOP (control B) and (d) incubated without 8-MOP (control C). Specular and light microscopic examination showed that the experimental corneas had greater cellular damage compared to the control corneas. The effects of 8-MOP were restricted to certain localized areas of the cornea. However there was no significant difference in the amounts of 51Cr released from the labelled experimental and control corneas. These results show phototoxic damage of the corneal endothelial cells

  13. Phototoxic effects of 8-methoxypsoralen on rabbit corneal endothelium

    Energy Technology Data Exchange (ETDEWEB)

    Menon, I.A.; Basu, P.K.; Hasany, S.M.; Persad, S.D. (Univ. of Toronto, Ontario (Canada))

    1989-01-01

    The phototoxic effects of 8-methoxypsoralen (8-MOP) were investigated using the rabbit corneal endothelium in organ culture. The corneas were divided into four groups: (a) irradiated with a mercury vapor lamp (emitting UVA and visible radiation) in the presence of 8-MOP (experimental), (b) irradiated without 8-MOP (control A), (c) incubated with 8-MOP (control B) and (d) incubated without 8-MOP (control C). Specular and light microscopic examination showed that the experimental corneas had greater cellular damage compared to the control corneas. The effects of 8-MOP were restricted to certain localized areas of the cornea. However there was no significant difference in the amounts of 51Cr released from the labelled experimental and control corneas. These results show phototoxic damage of the corneal endothelial cells.

  14. Research Progress in Corneal Cross-linking Agents

    Institute of Scientific and Technical Information of China (English)

    Na Li; Xiujun Peng; Zhengjun Fan

    2014-01-01

    Corneal collagen cross-linking with UVA-riboflavin is cur-rently the only method for preventing the progression of kera-toconus from the pathological perspective. Topical application of a direct cross-linking agent is now attracting widespread at-tention in clinical settings..This article reviews the research progress in the application of indirect or direct cross-linking agents (e.g., riboflavin, glucose, ribose, glutaraldehyde, formaldehyde,.glyceraldehyde,.short chain aliphatic β-nitro alcohol, and genipin) in the treatment of corneal diseases and analyzes the cross-linking efficacy,.toxicity,.and merits and disadvantages of each cross-linking agent,.providing clinical information for further studies.

  15. Transient Anisocoria after Corneal Collagen Cross-Linking

    Directory of Open Access Journals (Sweden)

    George D. Kymionis

    2014-01-01

    Full Text Available Purpose. To report a case with transient anisocoria after corneal collagen cross-linking (CXL. Methods. Case report. Results. A 24-year-old male underwent corneal collagen cross-linking (CXL in his right eye for keratoconus. At the end of the procedure, the pupil of the treated eye was irregular and dilated, while the pupil of the fellow eye was round, regular, and reactive (anisocoria. The following day, pupils were round, regular, and reactive in both eyes. Conclusion. Anisocoria may be a transient and innocuous complication after CXL. A possible cause for this complication might be the anesthetic drops used before and during the surgical procedure or/and the ultraviolet A irradiation during the treatment.

  16. Topical antibiotics in the management of corneal ulcer

    Directory of Open Access Journals (Sweden)

    Reddy P

    1988-01-01

    Full Text Available A total of 82 patients suffering from corneal ulcer were treated with framycetin 0.5%, gentamicin 3 mg./ml, chloramphenicol 0.4% and a neomycin combination containing Polymixin B sulphate 5000 u, neomycin sulphate 1700 u and gramicidin 0.025 mg/mL in a Randomised comparative study. The commonest organism isolated was Staphylococcus followed by Pneumococcus, Streptococcus and Pseudomonas. The in vitro sensitivity of these isolates to framycetin was higher than that to others Framycetin produced both earlier and a greater degree of improvement in mean score of signs and symptoms than the other antibiotics. It can thus be concluded that framycetin has a better profile of antibacterial activity and clinical efficacy than some other commonly used topical antibiotics in the treatment of corneal ulcer.

  17. Toxicity of methods of implant material sterilization on corneal endothelium

    International Nuclear Information System (INIS)

    The toxicity of different procedures utilized for the sterilization of intraocular implant material was assessed on the endothelium of organ-cultured porcine corneas. Polymethylmethacrylate lenses sterilized by treatment with sodium hydroxide (NaOH), ethylene oxide, formaldehyde, and gamma radiation were added to a culture medium containing normal porcine corneas. Considering the viability of endothelial cells, appearance of intracellular degenerative vacuoles, and denudation of corneal Descemet's membrane as criterion for the evaluation of toxicity of different methods of sterilization, the NaOH-treated lenses were found to be the least toxic to porcine corneal endothelium. Phase-contrast microscopy and vital staining of the endothelium permitted direct viewing of the endothelium aiding in the assessment of toxicity

  18. Molecular underpinnings of corneal angiogenesis: advances over the past decade

    Science.gov (United States)

    Abdelfattah, Nizar Saleh; Amgad, Mohamed; Zayed, Amira A.; Hussein, Heba; Abd El-Baky, Nawal

    2016-01-01

    The cornea is maintained in an avascular state by maintaining an environment whereby anti-angiogenic factors take the upper hand over factors promoting angiogenesis. Many of the common pathologies affecting the cornea involve the disruption of such equilibrium and the shift towards new vessel formation, leading to corneal opacity and eventually-vision loss. Therefore it is of paramount importance that the molecular underpinnings of corneal neovascularization (CNV) be clearly understood, in order to develop better targeted treatments. This article is a review of the literature on the recent discoveries regarding pro-angiogenic factors of the cornea (such as vascular endothelial growth factors, fibroblast growth factor and matrix metalloproteinases) and anti-angiogenic factors of the cornea (such as endostatins and neostatins). Further, we review the molecular underpinnings of lymphangiogenesis, a process now known to be almost separate from (yet related to) hemangiogenesis. PMID:27275438

  19. Keratometry and corneal topography using multiple delay element OCT

    Science.gov (United States)

    Plesea, Lucian; Podoleanu, Adrian G.

    2008-02-01

    We have presented previously a novel method for the evaluation of the surface shape of an object, with immediate application to measurement of cornea shape. This method uses single shot C-scans obtained by using a multiple delay element (MDE) in the reference path of an OCT system. A calibrated MDE-OCT system can be used to measure the elevation of points on the cornea, in contrast to existing methods which are based on measurement of the cornea slope. The associated algorithm for extracting corneal topography data points from the MDE-OCT C-Scan image will be presented, data points which can then be used to calculate the Zernike coefficients for the cornea shape. The differences between the existing systems and the MDE-OCT method for keratometry and corneal topography are discussed.

  20. SYNTHESIS OF ROBOTIC MECHANISM FOR MICROSURGICAL CORNEAL GRAFTING

    Institute of Scientific and Technical Information of China (English)

    Hu Yida; Zhao Zhiwen; Li Dazhai; Zong Guanghua

    2005-01-01

    In order to enhance the effect of corneal grafting, an assisting microsurgical robot has been developed. As one of principal issues for the robotic system design, type and size synthesis of the robotic mechanism is discussed. For this purpose, timeline subtask is analyzed with surgical component motion in manual corneal grafting microsurgery, as the reference of robotic mechanism synthesis. On the basis of study on the kinematic correlation between the arm structures and the wrist structures, configuration of joint is determined for the surgical task and motion in type synthesis of the mechanism. The objective for size synthesis of robotic mechanism is optimization of the mechanism dexterity as a manipulation capability. The condition number based on Jacob matrix is chosen as dexterity measure of the mechanism. The prototype is developed.