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Sample records for acrylic intraocular lenses

  1. Evaluation of in vitro glistening formation in hydrophobic acrylic intraocular lenses

    OpenAIRE

    Thomes BE; Callaghan TA

    2013-01-01

    Brett E Thomes, Thomas A CallaghanAlcon Research Ltd (A Novartis Company), Fort Worth, TX, USAPurpose: To evaluate the impact of continuous manufacturing process improvements on glistening formation in AcrySof hydrophobic acrylic intraocular lenses (IOLs) by comparing lenses manufactured in 2003 with lenses manufactured in 2012.Methods: Glistenings were experimentally created as aqueous-filled microvacuoles utilizing an accelerated laboratory method by immersing the lens in water at 45&de...

  2. Comparison of Nd: YAG capsulotomy rate between 1-piece and 3-piece acrylic intraocular lenses: A STROBE-compliant article.

    Science.gov (United States)

    Kim, Sun Young; Chung, Young Kwon; Shin, Hye Young; Lee, Mee Yon; Lee, Young-Chun; Kim, Su-Young

    2017-07-01

    The aim of the study is to compare Nd:YAG capsulotomy rate between acrylic 1- and 3-piece intraocular lenses. Among 924 eyes of 762 patients who received cataract surgery, we selected the 303 patients (404 eyes) implanted with an SN60WF 1-piece intraocular lens (Alcon, Fort Worth, TX) or a YA-60BBR 3-piece intraocular lens (Hoya Co., Tokyo, Japan). For intraindividual comparison, we enrolled the 17 patients implanted with an SN60WF in 1 eye and a YA-60BBR in the contralateral eye. We compared Nd:YAG capsulotomy rate between acrylic 1- and 3-piece intraocular lenses 24 months after the operation. Of the 404 eyes in this study, Nd:YAG capsulotomy was performed in 20 of 268 eyes (7.5%) in the SN60WF 1-piece intraocular lens group and 24 of 136 eyes (17.6%) in the YA-60BBR 3-piece intraocular lens group; the difference was statistically significant (P = .002). Among the 17 patients (34 eyes) who were implanted with 2 different inraocular lenses, Nd:YAG capsulotomy was performed in only 2 eyes (12%) in the SN60WF group and 9 eyes (53%) in the YA-60BBR group; the difference was statistically significant (P = .020).The authors found a significantly greater incidence of Nd:YAG capsulotomy in eyes who received 3-piece lenses compared with those who received 1-piece lenses.

  3. Findings of an experimental study in a rabbit model on posterior capsule opacification after implantation of hydrophobic acrylic and hydrophilic acrylic intraocular lenses

    Directory of Open Access Journals (Sweden)

    Nikolaos Trakos

    2009-01-01

    Full Text Available Nikolaos Trakos1, Elli Ioachim2, Elena Tsanou2, Miltiadis Aspiotis1, Konstantinos Psilas1, Chris Kalogeropoulos11University Eye Clinic of Ioannina, Ioannina, Greece; 2Pathology Department, University of Ioannina, Ioannina, GreecePurpose: Study on cell growth on the posterior capsule after implantation of hydrophobic acrylic (Acrysof SA 60 AT and hydrophilic acrylic (Akreos Disc intraocular lenses (IOL in a rabbit model and comparison of posterior capsule opacification (PCO.Methods: Phacoemulsification was performed in 22 rabbit eyes, and two different IOL types (Acrysof SA60 AT and Akreos Disc were implanted. These IOLs had the same optic geometry (square edged but different material and design. Central PCO (CPCO, peripheral PCO (PPCO, Sommering’s ring (SR formation, type of growth, extension of PCO, cell type, inhibition, and fibrosis were evaluated three weeks after surgery. Histological sections of each globe were prepared to document the evaluation of PCO.Results: No statistically significant difference was observed between a hydrophobic acrylic IOL and a hydrophilic acrylic IOL in relation to the CPCO, PPCO, type of growth, extension, cell type, inhibition, and fibrosis. Statistically significant difference was observed in relation to the formation of SR with Acrysof SA 60 AT group presenting more SR than Akreos Disc group.Conclusion: PCO was not influenced by the material of the IOL or the design of the haptics of the IOLs we studied.Keywords: posterior capsule opacification, intraocular lenses, rabbit model

  4. Comparison of AcrySof MA30BA and Sensar AR40 acrylic intraocular lenses.

    Science.gov (United States)

    Casprini, Fabrizio; Tosi, Gian Marco; Quercioli, Pier Paolo; Caporossi, Aldo

    2002-07-01

    To compare differences in anterior (ACO) and posterior (PCO) capsule opacification and subjective glare between 2 acrylic intraocular lenses (IOLs): AcrySof MA30BA (Alcon) and Sensar AR40 (Allergan). Department of Ophthalmology and Neurosurgery, University of Siena, Siena, Italy. This retrospective study comprised 100 cataract patients who had phacoemulsification and IOL implantation. Fifty eyes of 50 patients received an MA30BA and 50 eyes of 50 patients, an AR40. The mean postoperative follow-up was 25 months (range 20 to 31 months) and 22 months (range 19 to 29 months), respectively. Examiners subjectively evaluated ACO, and a photographic image-analysis system was used to assess PCO. All patients received a questionnaire to evaluate the incidence of subjective photic phenomena. In the MA30BA group, 60% had no ACO, 19% had mild ACO, and 21% had anterior capsule fibrosis. In the AR40 group, 55% had no ACO, 27% had mild ACO, and 18% had anterior capsule fibrosis. In the MA30BA group, the mean PCO score measured by image-analysis was 0.043 (range 0.000 to 0.084) at 1 year and 0.125 (range 0.000 to 0.197) at 2 years and in the AR40 group, 0.071 (range 0.000 to 0.157) and 0.230 (range 0.091 to 0.628), respectively. Although the ACO percentages and the PCO scores at 1 year were not statistically different between the 2 groups (P >.05), the MA30BA group had statistically less PCO at 2 years (P .05). The findings indicate that the AcrySof MA30BA has a lower incidence of PCO than the Sensar AR40. The AR40 IOL induced less glare; however, the glare phenomena did not disturb those with an MA30BA lens and the symptoms decreased by 1 year after surgery. These results suggest that both optic design and haptic material influence postoperative clinical results.

  5. Light transmittance of 1-piece hydrophobic acrylic intraocular lenses with surface light scattering removed from cadaver eyes.

    Science.gov (United States)

    Werner, Liliana; Morris, Caleb; Liu, Erica; Stallings, Shannon; Floyd, Anne; Ollerton, Andrew; Leishman, Lisa; Bodnar, Zachary

    2014-01-01

    To assess the potential effect of surface light scattering on light transmittance of 1-piece hydrophobic acrylic intraocular lenses (IOLs) with or without a blue-light filter. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Intraocular lenses were obtained from human cadavers (49 IOLs total; 36 with blue-light filter) and from finished-goods inventory (controls). The IOLs were removed from cadaver eyes and the power and model matched to unused controls. After surface proteins were removed, the IOLs were hydrated for 24 hours at room temperature. Surface light scattering was measured with a Scheimpflug camera (EAS-1000 Anterior Segment Analysis System). Light transmittance was measured with a Lambda 35 UV/Vis spectrophotometer (single-beam configuration; RSA-PE-20 integrating sphere). Hydrated scatter values ranged from 4.8 to 202.5 computer-compatible tape (CCT) units for explanted IOLs with blue-light filter and 1.5 to 11.8 CCT units for controls; values ranged from 6.0 to 137.5 CCT units for explanted IOLs without a blue-light filter and 3.5 to 9.6 CCT units for controls. In both groups, there was a tendency toward increasing scatter values with increasing postoperative time. No differences in light transmittance were observed between explanted IOLs and controls in both groups (IOLs with blue-light filter: P=.407; IOL with no blue-light filter: P=.487; both paired t test). Although surface light scattering of explanted IOLs was significantly higher than that of controls and appeared to increase with time, no effect was observed on light transmittance of 1-piece hydrophobic acrylic IOLs with or without a blue-light filter. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  6. Influence of surface light scattering in hydrophobic acrylic intraocular lenses on laser beam transmittance.

    Science.gov (United States)

    Shiraya, Tomoyasu; Kato, Satoshi; Minami, Keiichiro; Miyata, Kazunori

    2017-02-01

    The aim of this study was to experimentally examine the changes in the transmittances of photocoagulation lasers when surface light scattering increases in AcrySof intraocular lenses (IOLs). SA60AT IOLs (Alcon) were acceleratingly aging for 0, 3, 5, and 10 years to simulate surface light scattering, and the surface light-scattering intensities of both IOL surfaces were measured using a Scheimpflug photographer. The powers of laser beams that passed from a laser photocoagulator through the aged IOLs were measured at 532, 577, and 647 nm. Changes in the laser power and transmittance with the years of aging and the intensities of surface light scattering were examined. Although the intensity of surface light scattering increased with the years of aging, the laser power did not change with the years of aging (P > 0.30, Kruskal-Wallis test). There were no significant changes in the laser transmittance with the years of aging or the laser wavelength (P > 0.30 and 0.57, respectively). The intensity of surface light scattering revealed no significant association with the laser transmittance at any wavelength (P > 0.37, liner regression). The increases in the surface light scattering of the AcrySof IOLs would not influence retinal photocoagulation treatments for up to 10 years after implantation.

  7. Surface modification of acrylate intraocular lenses with dielectric barrier discharge plasma at atmospheric pressure

    Institute of Scientific and Technical Information of China (English)

    WANG Yao; LIU ZhenMei; XU ZhiKang; YAO Ke

    2009-01-01

    Surface modification with dielectric barrier discharge (DBD) plasma was carried out at atmospheric pressure (argon as the discharge gas) to improve the biocompatibility of hydrophobic acrylate intraocular lens (IOL). Changes of the plasma-treated IOL surface in chemical composition,morphology and hydrophilicity were comprehensively evaluated by X-ray photoelectron spectroscopy (XPS),field emission scanning electron microscopy (FESEM),atomic force microscopy (AFM) and water contact angle (WCA) measurements. The surface biocompatibility of the untreated and plasma-treated IOLs was compared with the adhesion behavior of platelets,macrophages and lens epithelial cells (LECs) in vitro. After DBD plasma treatment,the hydrophilicity of the IOL surface was obviously improved. The changes in WCA with treatment extension may be attributed to both the introduction of oxygen or/and nitrogen-containing polar groups and the increase of surface roughness induced by plasma etching effect. The existence of low molecular weight oxidized material (LMWOM) was proved on the plasma treated IOL which was caused by the chain scission effect of the plasma treatment. The plasma-treated lOLs resisted the adhesion of platelets and macrophages significantly. The LECs spreading and proliferation were postponed on the lOLs plasma-treated for more than 180 s,with a well maintained epithelial phenotype of LECs. The IOL biocompatibility was improved after the DBD plasma treatment. We speculate that slighter foreign-body reaction and later incidence of anterior capsule opacification (ACO) may be expected after implantation of the argon DBD plasma-treated IOL.

  8. Surface modification of acrylate intraocular lenses with dielectric barrier discharge plasma at atmospheric pressure

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Surface modification with dielectric barrier discharge(DBD) plasma was carried out at atmospheric pressure(argon as the discharge gas) to improve the biocompatibility of hydrophobic acrylate intraocular lens(IOL).Changes of the plasma-treated IOL surface in chemical composition,morphology and hydrophilicity were comprehensively evaluated by X-ray photoelectron spectroscopy(XPS),field emission scanning electron microscopy(FESEM),atomic force microscopy(AFM) and water contact angle(WCA) measurements.The surface biocompatibility of the untreated and plasma-treated IOLs was compared with the adhesion behavior of platelets,macrophages and lens epithelial cells(LECs) in vitro.After DBD plasma treatment,the hydrophilicity of the IOL surface was obviously improved.The changes in WCA with treatment extension may be attributed to both the introduction of oxygen or/and nitrogen-containing polar groups and the increase of surface roughness induced by plasma etching effect.The existence of low molecular weight oxidized material(LMWOM) was proved on the plasma-treated IOL which was caused by the chain scission effect of the plasma treatment.The plasma-treated IOLs resisted the adhesion of platelets and macrophages significantly.The LECs spreading and proliferation were postponed on the IOLs plasma-treated for more than 180 s,with a well maintained epithelial phenotype of LECs.The IOL biocompatibility was improved after the DBD plasma treatment.We speculate that slighter foreign-body reaction and later incidence of anterior capsule opacification(ACO) may be expected after implantation of the argon DBD plasma-treated IOL.

  9. Late opacification of a hydrophilic acrylic intraocular lens

    Directory of Open Access Journals (Sweden)

    Al-Bdour Muawyah

    2008-01-01

    Full Text Available Cataract extraction and intraocular lens implantation is considered to be a safe procedure in most cases. However, the new advances in the surgical technique namely phacoemulsification and hence the increased use of foldable intraocular lenses have given rise to new complications including late opacification of intraocular lenses. In this case we report late opacification of a foldable hydrophilic acrylic intraocular lens and the surgical technique for its exchange.

  10. Softec HD hydrophilic acrylic intraocular lens: biocompatibility and precision

    Directory of Open Access Journals (Sweden)

    Ladan Espandar

    2011-01-01

    Full Text Available Ladan Espandar1, Shameema Sikder2, Majid Moshirfar31Department of Ophthalmology, Tulane University, New Orleans, LA, USA; 2Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA; 3John A Moran Eye Center, University of Utah, Salt Lake City, UT, USAAbstract: Intraocular lens development is driven by higher patient expectations for ideal visual outcomes. The recently US Food and Drug Administration-approved Softec HD™ lens is an aspheric, hydrophilic acrylic intraocular lens (IOL. The hydrophilic design of the lens is optimized to address dysphotopsia while maintaining biocompatibility, optical clarity, resistance to damage, and resistance to biocontamination. Aspheric lenses decrease postoperative spherical aberration. The addition of the Softec lens provides clinicians with another option for IOL placement; however, randomized comparative studies of this lens to others already on the market remain to be completed.Keywords: hydrophilic acrylic intraocular lens, Softec HD intraocular lens, aspheric intraocular lens, IOL

  11. Comparison of Anterior Capsule Stability Following Implantation of Three Single Piece Acrylic Intraocular Lenses with Different Haptic Design.

    Science.gov (United States)

    Yang, Soonwon; Lim, Sung A; Na, Kyung-Sun; Joo, Choun-Ki

    2017-02-01

    To compare the anterior capsule contraction and intraocular lens (IOL) decentration among three types of IOL to determine the influence of haptic design on anterior capsule stability. One hundred fifty patients were enrolled in this prospective, randomized study and 260 eyes underwent implantation of one of the following IOLs: modified L-haptic IOL (n = 74), modified C-haptic IOL (n = 97), or a plate-haptic IOL (n = 89). The area of the anterior capsule opening, IOL decentration, and capsule overlap were measured using retroillumination photospot 1 day and 2 months after cataract surgery. The area of capsule opening at postoperative day 1 was significantly different between the three IOLs (p haptic IOL (p haptic IOLs were less than those in modified C-haptic IOLs and comparable to those in plate-haptic IOLs.

  12. Developments in Accommodating Intraocular Lenses

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    Zeki Tunç

    2012-07-01

    Full Text Available Technical progress in cataract surgery has decreased the incidence of severe complications in this type of surgery. The introduction of micro incision cataract surgery (MICS (sub- 2.0 mm incision allow the surgeon to achieve better postoperative control of astigmatism and higherorder aberration (HOAs with minimum induction of both. It is believed that multifocal lenses provide very successful results, however, there are limitations to these. Implantation of accommodating intraocular lenses (IOLs is an option to treat presbyopia. The IOLs work by using the continued functionality of the ciliary muscle after cataract removal. Accommodating IOLs were designed to avoid the optical side effects of multifocal IOLs. Two main design concepts exist. First, axial shift concepts rely on anterior axial movement of one or two optics creating accommodative ability. Second, curvature change designs are designed to provide significant amplitudes of accommodation with little physical displacement. Accommodative IOLs to correct astigmatism and HOAs in the future are needed. (Turk J Ophthalmol 2012; 42: 288-93

  13. Surface Modification of Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Qi Huang

    2016-01-01

    Full Text Available Objective: This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs. Data Sources: All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect. Study Selection: The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded. Results: Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol, polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO 2 , heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments. Conclusion: The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs.

  14. DESIGN OF THE MULTIORDER INTRAOCULAR LENSES

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    V. G. Kolobrodov

    2015-01-01

    Full Text Available Intraocular lenses (IOLs are used to replace the natural crystalline lens of the eye. Just few basic designs of IOLs are used clinically. Multiorder diffractive lenses (MODL which operate simultaneously in several diffractive orders were proposed to decrease the chromatic aberration. Properties analysis of MODL showed a possibility to use them to develop new designs of IOLs. The purpose of this paper was to develop a new method of designing of multiorder intraocular lenses with decreased chromatic aberration. The theoretical research of the lens properties was carried out. The diffraction efficiency dependence with the change of wavelength was studied. A computer simulation of MODL in a schematic model of the human eye was carried out. It is found the capability of the multiorder diffractive lenses to focus polychromatic light into a segment on the optical axis with high diffraction efficiency. At each point of the segment is present each component of the spectral range, which will build a color image in combination. The paper describes the new design method of intraocular lenses with reduced chromaticism and with endless adaptation. An optical system of an eye with an intraocular lens that provides sharp vision of objects located at a distance of 700 mm to infinity is modeled.

  15. Effect of four different intraocular lenses on posterior capsule opacification

    Institute of Scientific and Technical Information of China (English)

    Rahmi; Duman; Fatih; Karel; Pelin; ?zyol; Can; Ates

    2015-01-01

    AIM: To evaluate the impact of 4 different intraocular lenses(IOLs) on posterior capsule opacification(PCO) by comparing the neodymium: yttrium-aluminum-garnet(Nd:YAG) laser capsulotomy rates.METHODS: This retrospective study included 4970 eyes of 4013 cataract patients who underwent phacoemulsification and IOL implantation between January 2000 and January 2008 by the same surgeon at one clinic. Four different IOLs were assessed. The outcome parameter was the incidence of Nd:YAG laser posterior capsulotomies.· RESULTS: An Nd:YAG laser posterior capsulotomy was performed in 153(3.07%) of the 4970 eyes. The mean follow-up time was 84 mo for all of the IOL groups. The percentage of eyes developing PCO was significantly greater for the acrylic hydrophilic IOLs than for the hydrophobic IOLs, although eyes with acrylic hydrophilic IOLs did not require Nd:YAG laser capsulotomy as soon as eyes with acrylic hydrophobic IOLs. There was no difference between the long-term PCO rates when 1-and 3-piece acrylic hydrophobic IOLs were compared or when IOLs made of the same material but with different haptic angles were compared.· CONCLUSION: In this study, eyes with acrylic hydrophilic IOLs were more likely to develop PCO than those with acrylic hydrophobic IOLs. The lens design(1-piece versus 3-piece and varying haptic angles) did not affect the PCO rate.

  16. UV solid state laser ablation of intraocular lenses

    Science.gov (United States)

    Apostolopoulos, A.; Lagiou, D. P.; Evangelatos, Ch.; Spyratou, E.; Bacharis, C.; Makropoulou, M.; Serafetinides, A. A.

    2013-06-01

    Commercially available intraocular lenses (IOLs) are manufactured from silicone and acrylic, both rigid (e.g. PMMA) and foldable (hydrophobic or hydrophilic acrylic biomaterials), behaving different mechanical and optical properties. Recently, the use of apodizing technology to design new diffractive-refractive multifocals improved the refractive outcome of these intraocular lenses, providing good distant and near vision. There is also a major ongoing effort to refine laser refractive surgery to correct other defects besides conventional refractive errors. Using phakic IOLs to treat high myopia potentially provides better predictability and optical quality than corneal-based refractive surgery. The aim of this work was to investigate the effect of laser ablation on IOL surface shaping, by drilling circular arrays of holes, with a homemade motorized rotation stage, and scattered holes on the polymer surface. In material science, the most popular lasers used for polymer machining are the UV lasers, and, therefore, we tried in this work the 3rd and the 5th harmonic of a Q-switched Nd:YAG laser (λ=355 nm and λ=213 nm respectively). The morphology of the ablated IOL surface was examined with a scanning electron microscope (SEM, Fei - Innova Nanoscope) at various laser parameters. Quantitative measurements were performed with a contact profilometer (Dektak-150), in which a mechanical stylus scanned across the surface of gold-coated IOLs (after SEM imaging) to measure variations in surface height and, finally, the ablation rates were also mathematically simulated for depicting the possible laser ablation mechanism(s). The experimental results and the theoretical modelling of UV laser interaction with polymeric IOLs are discussed in relation with the physical (optical, mechanical and thermal) properties of the material, in addition to laser radiation parameters (laser energy fluence, number of pulses). The qualitative aspects of laser ablation at λ=213 nm reveal a

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    Lifescience Database Archive (English)

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  1. Drug-Eluting Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Angel Concheiro

    2011-11-01

    Full Text Available Notable advances in materials science and in surgical techniques make the management of cataract by replacement of the opaque crystalline with an intraocular lens (IOL, one of the most cost-effective interventions in current healthcare. The usefulness and safety of IOLs can be enhanced if they are endowed with the ability to load and to sustain drug release in the implantation site. Drug-eluting IOLs can prevent infections and untoward reactions of eye tissues (which lead to opacification and also can act as drug depots for treatment of several other ocular pathologies. Such a myriad of therapeutic possibilities has prompted the design of drug-IOL combination products. Several approaches are under study, namely combination of the IOL with an insert in a single device, soaking in drug solutions, impregnation using supercritical fluids, coating with drug/polymer layers, and covalent grafting of the drug. The advantages/limitations of each technique are discussed in the present review on selected examples. Although more in vivo data are required, the information already available proves the interest of some approaches in ocular therapeutics.

  2. Softec HD hydrophilic acrylic intraocular lens: biocompatibility and precision

    OpenAIRE

    Ladan Espandar; Shameema Sikder; Majid Moshirfar

    2011-01-01

    Ladan Espandar1, Shameema Sikder2, Majid Moshirfar31Department of Ophthalmology, Tulane University, New Orleans, LA, USA; 2Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA; 3John A Moran Eye Center, University of Utah, Salt Lake City, UT, USAAbstract: Intraocular lens development is driven by higher patient expectations for ideal visual outcomes. The recently US Food and Drug Administration-approved Softec HD™ lens is an aspheric, hydrophilic acrylic intraocular le...

  3. Mechanical properties of intra-ocular lenses

    Science.gov (United States)

    Ehrmann, Klaus; Kim, Eon; Parel, Jean-Marie

    2008-02-01

    Cataract surgery usually involves the replacement of the natural crystalline lens with a rigid or foldable intraocular lens to restore clear vision for the patient. While great efforts have been placed on optimising the shape and optical characteristics of IOLs, little is know about the mechanical properties of these devices and how they interact with the capsular bag once implanted. Mechanical properties measurements were performed on 8 of the most commonly implanted IOLs using a custom build micro tensometer. Measurement data will be presented for the stiffness of the haptic elements, the buckling resistance of foldable IOLs, the dynamic behaviour of the different lens materials and the axial compressibility. The biggest difference between the lens types was found between one-piece and 3-piece lenses with respect to the flexibility of the haptic elements

  4. UV laser ablation patterns in intraocular lenses

    Science.gov (United States)

    Lagiou, D. P.; Evangelatos, Ch.; Apostolopoulos, A.; Spyratou, E.; Bacharis, C.; Makropoulou, M.; Serafetinides, A. A.

    2013-03-01

    The aim of this work is to investigate the effect of UV solid state laser radiation on intraocular lens (IOL) polymer surfaces as an alternative method to conventional surface shaping techniques for IOLs customization. Laser ablation experiments were performed on PMMA plates and commercially available hydrophobic and hydrophilic acrylic IOLs with the 5th harmonic of a Q-switched Nd:YAG laser (λ=213 nm). Circular arrays of holes were drilled on the polymer surface, covering the centre and the peripheries of the IOL. The morphology of the ablated IOL surface was examined with a conventional optical microscope (Leitz GMBH Wetzlar) and with a scanning electron microscope (SEM, Fei - Innova Nanoscope) at various laser parameters. Quantitative measurements of ablation rates were performed with a contact profilometer (Dektak-150), in which a mechanical stylus scanned across the surface of gold-coated IOLs (after SEM imaging) to measure variationsF in surface height. Laser interaction with IOLs depends on optical and mechanical material properties, in addition to laser radiation parameters. The exact ablation mechanism is discussed. Some polymer materials, depending on their properties, are more susceptible to the photothermal mechanism than the photochemical one or vice versa. In summary, every IOL polymer exhibits specific attributes in its interaction with the 5th harmonic of Nd:YAG laser.

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  6. Comparison of the Retinal Straylight in Pseudophakic Eyes with PMMA, Hydrophobic Acrylic, and Hydrophilic Acrylic Spherical Intraocular Lens

    Directory of Open Access Journals (Sweden)

    Ya-wen Guo

    2014-01-01

    Full Text Available Purpose. To investigate the intraocular straylight value after cataract surgery. Methods. In this study, 76 eyes from 62 patients were subdivided into three groups. A hydrophobic acrylic, a hydrophilic acrylic, and a PMMA IOL were respectively, implanted in 24 eyes, 28 eyes, and 24 eyes. Straylight was measured using C-Quant at 1 week and 1 month postoperatively in natural and dilated pupils. Results. The hydrophilic acrylic IOLs showed significantly lower straylight values than those of the hydrophobic acrylic IOLs in dilated pupils at 1 week and 1 month after surgery (P0.05. Moreover, no significant difference was found in straylight between natural and dilated pupils in each group at 1 week and 1 month postoperatively (P>0.05. Conclusions. Although the hydrophobic acrylic IOL induced more intraocular straylight, straylight differences among the 3 IOLs were minimal. Pupil size showed no effect on intraocular straylight; the intraocular straylight was stable 1 week after surgery.

  7. NEW MATERIAL FOR LOW-COST INTRAOCULAR LENSES

    NARCIS (Netherlands)

    JONGEBLOED, WL; VANDERVEEN, G; KALICHARAN, D; VANANDEL, MV; BARTMAN, G; WORST, JGF

    1994-01-01

    A UV-hardening lacquer material based on polyurethane, used in Philips compact disc lens systems, was tested as suitable material for low-cost intraocular lenses (IOLs). A slightly changed composition (code number I-0.5A) came out as the best and was subsequenly tested, with reference to poly(methyl

  8. Implante de lente intra-ocular dobrável acrílica em crianças Acrylic foldable intraocular lens implantation in children

    Directory of Open Access Journals (Sweden)

    Antonio Jordão Jr.

    2000-04-01

    Full Text Available Objetivos: Avaliar o uso de lentes intra-oculares dobráveis de acrílico na correção da afacia infantil. Métodos: Dez olhos de 10 pacientes com idades entre 3 e 9 anos portadores de catarata infantil foram operados e receberam o implante de lente intra-ocular dobrável de acrílico. Os pacientes foram acompanhados por um período que variou de 6 a 20 meses. Resultados: Após a medida da acuidade visual de todos no último retorno, encontramos uma melhora significativa em cinco pacientes. Em nenhum dos casos houve opacificação da cápsula posterior no período observado ou qualquer outra complicação pós-operatória. Conclusão: Apesar da pequena casuística, os resultados sugerem que o uso de lentes intra-oculares acrílicas proporciona a manutenção da transparência do eixo visual a curto e médio prazos.Purpose: To evaluate the results of the implantation of acrylic foldable intraocular lenses in children. Methods: Ten eyes from 10 children aged 3 to 9 years with infantile cataracts were operated and received an acrylic intraocular lens implantation. Follow-up ranged from 6 to 20 months after surgery. Results: The patients had their visual acuity measured at the last visit and a significant improvement in all but one patient was found. There was no posterior capsule opacification or any other surgical complication in this period. Conclusions: Although the number of cases is small, the results suggest that the use of acrylic intraocular lens provides a very good transparency of the visual axis in the short and medium term after surgery.

  9. Adherence and kinetics of biofilm formation of Staphylococcus epidermidis to different types of intraocular lenses under dynamic flow conditions.

    Science.gov (United States)

    Baillif, Stéphanie; Ecochard, René; Casoli, Emmanuelle; Freney, Jean; Burillon, Carole; Kodjikian, Laurent

    2008-01-01

    To compare the adherence and biofilm formation of Staphylococcus epidermidis under in vitro flow conditions on intraocular lenses (IOLs) made of 4 biomaterials: poly(methyl methacrylate) (PMMA), silicone, hydrophilic acrylic, and hydrophobic acrylic. Department of Ophthalmology, Croix-Rousse University Hospital and University Research Laboratory, Lyon, France. Intraocular lenses were placed in a bioreactor designed to replicate intraocular conditions. The model consisted of Tygon tubing connected to a vial. Three septa allowed the entry and elimination of the artificial aqueous humor and inoculation of the bacterial suspension. The first of 2 pumps moved the aqueous humor along the circuit; the second pump regulated the flow at which the nutritive environment was regenerated. At various times (12, 16, 24, 40, 48, 60, and 72 hours), IOLs were taken from this environment and the bound bacteria were removed and counted. The distribution of bacterial adhesion on the IOLs was modeled using polynomial Poisson regression. To test the effect of the IOL biomaterial on bacterial adhesion, likelihood ratio tests were performed. The model provided the kinetics of S epidermidis biofilm growth on IOLs. The biofilm growth on each of the 4 biomaterials occurred in 3 phases: latent, dynamic or accelerated growth, and linear growth. The extent of bacterial binding to IOLs increased from hydrophilic acrylic polymer to PMMA, hydrophobic acrylic, and silicone. The differences were statistically significant. Bacterial adhesion to and biofilm development on the IOL surface depended on the characteristics of the biomaterial.

  10. [Intraocular lenses for the correction of refraction errors. Part 1: phakic anterior chamber lenses].

    Science.gov (United States)

    Kohnen, T; Baumeister, M; Cichocki, M

    2005-10-01

    In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

  11. Calcification of different designs of silicone intraocular lenses in eyes with asteroid hyalosis.

    Science.gov (United States)

    Stringham, Jack; Werner, Liliana; Monson, Bryan; Theodosis, Raymond; Mamalis, Nick

    2010-08-01

    To describe the association between calcification of older and newer designs of silicone intraocular lenses (IOLs) and asteroid hyalosis. Case series with clinicopathologic correlation. Sixteen silicone IOLs explanted because of decreased visual acuity associated with opacifying deposits on the posterior optic surface. All 16 lenses underwent gross and light microscopic analyses. Selected lenses underwent alizarin red staining or scanning electron microscopy coupled with energy dispersive x-ray spectroscopy for elemental composition. Clinical data in each case were obtained by a questionnaire sent to the explanting surgeons. Clinical data in relation to 111 hydrophilic acrylic lenses explanted because of calcification also were assessed for comparison. Deposit morphologic features and location were evaluated under gross and light microscopy. The calcified nature of the deposits was assessed by histochemical staining and surface analyses. Clinical data obtained included age at IOL implantation, gender, implantation and explantation dates, as well as history of neodymium:yttrium-aluminum-garnet laser treatment. The presence of asteroid hyalosis in the affected eye was investigated for the explanted silicone and hydrophilic acrylic lenses. The 16 lenses were of 8 designs manufactured from different silicone materials, which were explanted 9.21+/-3.66 years after implantation. Neodymium:yttrium-aluminum-garnet laser applications performed in 12 cases partially removed deposits from the lens, followed by a gradual increase in their density after the procedures. The presence of asteroid hyalosis was confirmed in 13 cases; no notes regarding this condition were found in patient charts in the other 3 cases. The deposits were only on the posterior optic surface of the silicone lenses and were composed of calcium and phosphate. A history of asteroid hyalosis was not found in relation to any of the 111 cases of postoperative calcification of hydrophilic acrylic lenses

  12. Comparison of visual performance of multifocal intraocular lenses with same material monofocal intraocular lenses.

    Directory of Open Access Journals (Sweden)

    Tomofusa Yamauchi

    Full Text Available PURPOSE: To compare the visual performance of multifocal intraocular lenses (IOLs and monofocal IOLs made of the same material. METHODS: The subjects included patients implanted with either Tecnis® monofocal IOLs (ZA9003 or ZCB00 or Tecnis® multifocal IOLs (ZMA00 or ZMB00 bilaterally. We conducted a retrospective study comparing the two types of IOLs. The multifocal group included 46 patients who were implanted with Tecnis® multifocal IOLs bilaterally. The monofocal group was an age- and sex-matched control group, and included 85 patients who were implanted with Tecnis® monofocal IOLs bilaterally. Lens opacity grading, the radius of corneal curvature, corneal astigmatism, axial length and the refractive status were measured preoperatively. Pupil size, ocular aberrometry, distance, intermediate and near visual acuity, contrast sensitivity with and without glare and the responses to a quality-of-vision questionnaire were evaluated pre- and postoperatively. RESULTS: The uncorrected near visual acuity was significantly better in the multifocal group, whereas both the corrected intermediate and near visual acuity were better in the monofocal group. Contrast sensitivity (with and without glare was significantly better in the monofocal group. The rate of spectacle dependency was significantly lower in the multifocal group. There were no significant differences between the two groups regarding most items of the postoperative quality-of-vision questionnaire (VFQ-25, with the exception that the patients in the monofocal group reported fewer problems with nighttime driving. CONCLUSIONS: The multifocal IOLs used in this study reduced spectacle dependency more so than monofocal IOLs and did not compromise the subjective visual function, with the exception of nighttime driving.

  13. Light scattering and light transmittance in intraocular lenses explanted because of optic opacification.

    Science.gov (United States)

    Michelson, Jennifer; Werner, Liliana; Ollerton, Andrew; Leishman, Lisa; Bodnar, Zachary

    2012-08-01

    To assess light scattering and light transmittance in intraocular lenses (IOLs) explanted because of optic opacification. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Poly(methyl methacrylate) (PMMA) IOLs with snowflake degeneration, hydrophilic acrylic IOLs with different calcification patterns, and 1 calcified silicone IOL explanted from an eye with asteroid hyalosis were studied with gross and light microscopy. Light scattering was measured with an EAS-1000 Scheimpflug camera. Light transmittance was measured with a Lambda 35 UV/Vis spectrophotometer (single-beam configuration with RSA-PE-20 integrating sphere). Analyses were performed at room temperature in the hydrated state and compared with controls. The study evaluated 8 PMMA IOLs, 22 hydrophilic acrylic IOLs, and 1 silicone IOL. Light scattering was as follows: 208 to 223 computer-compatible tapes (CCTs) for PMMA IOLs with snowflake degeneration (control = 9 CCTs); 90 to 227 CCTs for calcified hydrophilic acrylic IOLs (controls = 12 to 23 CCTs); 223 CCTs for the calcified silicone IOL (control = 5 CCTs). The mean light transmittance in the visible light spectrum was 81.08% to 97.10% for PMMA IOLs (control = 98.80%); 78.94% to 97.32% for hydrophilic acrylic IOLs (controls = 97.32% to 98.66%); 94.68% for the silicone IOL (control = 97.74%). Intraocular lens opacification led to very high levels of light scattering and a potential for decreased light transmittance, which play a role in the development of symptoms such as glare and halos, decreased contrast sensitivity, and eventually decreased visual acuity. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  14. Magnetic resonance imaging diagnosis of intraocular lenses. Die kernspintomographische Diagnostik der Hinterkammerlinse

    Energy Technology Data Exchange (ETDEWEB)

    Tosch, U. (Strahlenklinik und Poliklinik, Universitaetsklinik Rudolf Virchow, Berlin (Germany)); Bleckmann, H. (Strahlenklinik und Poliklinik, Universitaetsklinik Rudolf Virchow, Berlin (Germany)); Kaczmarek, U. (Strahlenklinik und Poliklinik, Universitaetsklinik Rudolf Virchow, Berlin (Germany))

    1994-09-01

    Intraocular lenses were investigated by MRI to obtain information about the quality of this method. In experimental studies, seven lenses of between 0 and 30 diopters were visualized. By MRI it was possible to differentiate the various diameters of lenses. It was not possible to discriminate the material of the intraocular lenses. After these first studies the eyes of two corpses and eight patients were investigated. Because of the resolution of MRI it was possible to tell the diopter of implanted lenses. However, by use of MRI in the regular position, a tilting or decentration of the intraocular lens was demonstrated. (orig.)

  15. Effect of transscleral neodymium: YAG cyclophotocoagulation on intraocular lenses

    Energy Technology Data Exchange (ETDEWEB)

    Blomquist, P.H.; Gross, R.L.; Koch, D.D. (Baylor College of Medicine, Houston, TX (USA))

    1990-03-01

    A neodymium: YAG laser operating in the thermal mode was used to irradiate isolated intraocular lenses (IOLs) and to perform transscleral cyclophotocoagulation on pseudophakic autopsy eyes to investigate the potential damage to IOL haptics such irradiation may cause. In the isolated IOLs, 70 mJ of energy deformed and partially melted both polymethylmethacrylate (PMMA) and polypropylene haptics. One of the capsular-fixated PC-IOL haptics in an autopsy eye partially melted when irradiated with the maximum energy level (8.8 J), with the aiming beam focused 1 mm posterior to the limbus and maximal posterior focus offset.

  16. [Scheimpflug photography for the examination of phakic intraocular lenses].

    Science.gov (United States)

    Baumeister, M

    2014-10-01

    High myopia phakic intraocular lenses (IOL) have become an established means of surgical correction for high ametropia. Scheimpflug photography is one of the methods which are frequently applied for postoperative examination of the implants. Results from published studies employing Scheimpflug photography for examination of anterior chamber angle-fixated, iris-fixated and sulcus-fixated phakic IOLs were evaluated. In several published studies Scheimpflug photography was used to examine the position of the implant and opacification of the crystalline lens. The results provided valuable evidence for the improvement of phakic IOL design. Scheimpflug photography offers an easy to use, rapid non-contact examination of phakic IOLs.

  17. Aderência in vitro do Staphylococcus epidermidis e da Pseudomonas alcaligenes em lentes intra-oculares In vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to intraocular lenses

    Directory of Open Access Journals (Sweden)

    Patrícia Ioschpe Gus

    2006-06-01

    used in the experiment. Four of polymethylmethacrylate (PMMA, four of silicone, four of hidrogel and two of acrylic. Eight intraocular lenses were placed in eight test tubes containing 4 ml of Pseudomonas alcaligenes suspension, and six intraocular lenses were placed in six test tubes containing 4 ml of Staphylococcus epidermidis suspension. The bacterial suspension used for adherence tests was 10(8 colony-forming units per milliliter (CFU/mL which corresponds to 0.5 in the scale of McFarland. The lenses were incubated at 37° for two hours. After this, intraocular lenses were removed from the test tubes and dried twice with the use of distilled and sterile water. The material was spread on blood-agar for cultivation at 35-37°C and was evaluated every 24 hours up to 72 hours. In the samples where there was bacterial growth, the colonies were counted using the conventional laboratory methods. All assays were performed in duplicate. RESULTS: Adherence of Staphylococcus epidermidis to PMMA intraocular lenses was lower than to hydrogel and silicone intraocular lenses. Adherence of Pseudomonas alcaligenes to hydrogel intraocular lenses was lower than to PMMA, acrylic and silicone intraocular lenses. CONCLUSIONS: Results suggest that in vitro adherence of Staphylococcus epidermidis and Pseudomonas alcaligenes to intraocular lenses is influenced by type of material of the lens and by microorganism species. Bacterial adherence may play a role in the pathogenesis of some forms of endophthalmitis after cataract surgery. More in vitro and clinical studies are necessary to elucidate the mechanisms by which Staphylococcus epidermidis and Pseudomonas alcaligenes cause endophthalmitis.

  18. New two-point scleral-fixation technique for foldable intraocular lenses with four hollow haptics.

    Science.gov (United States)

    Liu, He-Ting; Jiang, Zheng-Xuan; Tao, Li-Ming

    2016-01-01

    The study was to report a new two-point scleral-fixation technique for foldable intraocular lenses with four haptics. Lenses were slid into the anterior chamber from a 2.8 mm corneal incision and fixed under two sclera flaps at two opposite points. The postoperative best-corrected visual acuities (BCVAs) of all patients were significantly better than their preoperative BCVA. The results demonstrate that two-point, scleral fixations of foldable, intraocular lenses might be practicable and effective.

  19. Comparison of PMMA, foldable silicone and foldable acrylic hydrophobic intraocular lenses in combined phacoemulsification and trabeculectomy Comparação entre lentes intra-oculares de PMMA, lentes dobráveis de silicone e lentes acrílicas hidrofóbicas dobráveis em cirurgias combinadas de facoemulsificação e trabeculectomia

    Directory of Open Access Journals (Sweden)

    Ernani Serpa Junior

    2005-02-01

    Full Text Available PURPOSE: To compare the postoperative results of phacotrabeculectomy with implantation of PMMA, foldable silicone or foldable hydrofobic acrylic intraocular lens (IOL. SETTING: Glaucoma unit, The Royal Liverpool University Hospital, Liverpool, United Kingdom. METHODS: We studied a total of 124 eyes of three consecutive groups of patients with glaucoma and cataract that underwent phacotrabeculectomy with implantation of a PMMA (30 eyes, a foldable silicone (57 eyes or a foldable acrylic (37 eyes IOL. Postoperative Snellen visual acuity and intraocular pressure (IOP, and early and late complications were assessed. All data were analyzed by means of c² test, Fisher's exact test, ANOVA/MANOVA tests or a combination whenever appropriate. RESULTS: In all three groups the early and late mean postoperative IOPs were significantly lower than the preoperative ones (p25 mmHg and hypotony (IOPOBJETIVO: Comparar os resultados pós-operatórios de facotrabeculectomias com implante de lentes intra-oculares de PMMA, dobráveis de silicone e acrílicas hidrofóbicas dobráveis. MÉTODOS: Estudo comparativo retrospectivo, realizado no Departamento de Glaucoma da "St. Paul's Eye Unit - The Royal Liverpool University Hospital", em Liverpool, Inglaterra, onde foram estudados um total de 124 olhos de três grupos consecutivos de pacientes com glaucoma e catarata que foram submetidos à cirurgia de facotrabeculectomia com implante de lentes intra-oculares (LIO de PMMA (30 olhos, dobráveis de silicone (57 olhos e acrílicas hidrofóbicas dobráveis (37 olhos. Foram registradas a visão e pressão intra-ocular (PIO pré e pós-operatória, assim como as complicações pós-operatórias precoces e tardias. Todos os dados foram analisados utilizando-se o teste c², teste exato de Fisher, teste de ANOVA/MANOVA ou uma combinação deles quando necessário. RESULTADOS: Nos três grupos as PIOs pós-operatórias precoces e tardias foram significativamente inferiores

  20. Intraocular lenses and clinical treatment in paediatric cataract

    Directory of Open Access Journals (Sweden)

    Camila Ribeiro Koch Pena

    2015-06-01

    Full Text Available Pediatric cataract is the most common treatable cause of blindness in children. Prevalence, etiology and morphology vary with the socioeconomic development. The treatment goal is to reduce amblyopia, being difficult management especially in unilateral cases. The decision on aphakia or primary intraocular lens should be individualized as well as correction with contact lens or spectacles. The intraocular lens single-piece hydrophobic acrylic are the most implanted in children and the preferably is in the capsular bag. The Sanders-Retzlaff-Kraff theoretic (SRK/T stressing that is described as more predictable, following Holladay I and SRK II and the recommendation is to under correction +6.0 or +8.0 dioptrias expecting the growth of the eye. The posterior capsule opacity is the most frequent complication and varies with the material choice of the lens. Glaucoma is the most serious postoperative complication and depends on the timing of the surgery, primary lens implantation and time of post surgical follow-up. The adherence to occlusion therapy with patching is critical to the visual prognosis and is determined by the child’s age and laterality of the cataract. There was significant improvement in the surgery and in IOLs, however the final visual prognosis is still not desirable.

  1. Psychophysical Vision Simulation of Diffractive Bifocal and Trifocal Intraocular Lenses

    Science.gov (United States)

    Brezna, Wolfgang; Lux, Kirsten; Dragostinoff, Nikolaus; Krutzler, Christian; Plank, Nicole; Tobisch, Rainer; Boltz, Agnes; Garhöfer, Gerhard; Told, Reinhard; Witkowska, Katarzyna; Schmetterer, Leopold

    2016-01-01

    Purpose The visual performance of monofocal, bifocal, and trifocal intraocular lenses was evaluated by human individuals using a vision simulator device. This allowed investigation of the visual impression after cataract surgery, without the need actually to implant the lenses. Methods The randomized, double-masked, three-way cross-over study was conducted on 60 healthy male and female subjects aged between 18 and 35 years. Visual acuity (Early Treatment Diabetic Retinopathy Study; ETDRS) and contrast sensitivity tests (Pelli-Robson) under different lighting conditions (luminosities from 0.14–55 cd/m2, mesopic to photopic) were performed at different distances. Results Visual acuity tests showed no difference for corrected distance visual acuity data of bi- and trifocal lens prototypes (P = 0.851), but better results for the trifocal than for the bifocal lenses at distance corrected intermediate (P = 0.021) and distance corrected near visual acuity (P = 0.044). Contrast sensitivity showed no differences between bifocal and trifocal lenses at the distant (P = 0.984) and at the near position (P = 0.925), but better results for the trifocal lens at the intermediate position (P = 0.043). Visual acuity and contrast sensitivity showed a strong dependence on luminosity (P < 0.001). Conclusions At all investigated distances and all lighting conditions, the trifocal lens prototype often performed better, but never worse than the bifocal lens prototype. Translational Relevance The vision simulator can fill the gap between preclinical lens development and implantation studies by providing information of the perceived vision quality after cataract surgery without implantation. This can reduce implantation risks and promotes the development of new lens concepts due to the cost effective test procedure. PMID:27777828

  2. The effect of ionizing radiation on intraocular lenses.

    Science.gov (United States)

    Ellerin, B E; Nisce, L Z; Roberts, C W; Thornell, C; Sabbas, A; Wang, H; Li, P M; Nori, D

    2001-09-01

    The native crystalline lens is the principal shield against ultraviolet radiation (UV), damage to the human retina. Every year in the United States, more than one million patients undergo removal of the natural lens in the course of cataract surgery (phakectomy), at which time an intraocular lens (IOL) is placed in the lens capsule. The IOL thenceforth serves as the principal barrier to ultraviolet radiation over the life of the implant, potentially for decades. The synthetic organic molecules of which IOLs are composed offer little UV protection unless ultraviolet-absorbing chromophores are incorporated into the lens material during manufacture. However, chromophores are alkenes potentially subject to radiolytic degradation. It is unknown whether ionizing radiation at clinical doses (e.g., to the brain or in the head-and-neck region) affects the UV-absorbing capacity of chromophore-bearing IOLs and consequently exposes the retina to potentially chronic UV damage. In addition, the polymers of which IOLs are composed are themselves subject to radiation damage, which theoretically might result in optical distortion in the visible light range. To determine whether megavoltage photon ionizing radiation alters the absorption spectra of ultraviolet-shielding polymethylmethacrylate (PMMA) and organopolysiloxane (silicone) intraocular lenses (IOLs) in the UV (280 nm ionizing irradiation to doses of 2, 5, 10, 20, 40, 60, and 100 Gray, respectively. Because of artifactual aberrations inherent in analyzing convex lenses on a conventional flat-plate spectrophotometer, post-irradiation absorption spectra were subsequently reanalyzed on a Cary 300 spectrophotometer outfitted with a Labsphere Diffused Reflectance Accessory (DRA-CA-30-I) incorporating a Spectralon-coated integrating sphere. Primary: Changes in UV absorbance after irradiation. Secondary: Changes in visible and low-end near-infrared absorbance after irradiation. Photon ionizing radiation in the 2-Gy to 100-Gy range

  3. Extracapsular cataract extraction : the fate of retained lens material and intraocular lenses

    NARCIS (Netherlands)

    J.P. Kappelhof (Johan)

    1987-01-01

    textabstractThe aim of this study was to examine the fate of the lens material that remains in the eye after an extracapsular cataract extraction both with and without insertion of an intraocular lens. Apart from this, the development of precipitates on the intraocular lenses was morphologically inv

  4. Determination of scattering in intraocular lenses by spectrophotometric measurements.

    Science.gov (United States)

    Artigas, José M; Felipe, Adelina; Navea, Amparo; García-Domene, M Carmen; Pons, Álvaro; Mataix, Jorge

    2014-12-01

    This study presents a method for measuring scattering in explanted intraocular lenses (IOLs). Currently, determining scattering in IOLs is usually performed by Scheimpflug cameras and the results are expressed in the units used by this apparatus. The method we propose uses a spectrophotometer and this makes it possible to measure the total transmission of the IOL by using an integrating sphere; the direct transmission is determined by the double-beam mode. The difference between these two transmissions gives a value of the scattering in percentage values of light lost. In addition, by obtaining the spectral transmission curve, information about the most scattered wavelengths is also obtained. The IOL power introduces errors when directly measured, particularly with high powers. This problem can be overcome if a tailor-made cuvette is used that shortens the distance between the IOL and the condensing lens of the spectrophotometer when the IOL powers are below 24 diopters. We checked the effectiveness of this method by measuring the scattering of three explanted IOLs from cornea donors. This method, however, does not make it possible to ascertain whether the scattering measured is caused by surface light scattering or internal light scattering.

  5. Customized computer models of eyes with intraocular lenses

    Science.gov (United States)

    Rosales, P.; Marcos, S.

    2007-03-01

    We compared experimental wave aberrations in pseudophakic eyes with aspheric intraocular lenses (IOLs) to simulate aberrations from numerical ray tracing on customized computer eye models using corneal topography, angle λ, ocular biometry, IOL geometry, and IOL tilt and decentration measured on the same eyes. We found high correlations between real and simulated aberrations even for the eye with only the cornea, and these increased on average when the IOL geometry and position were included. Relevant individual aberrations were well predicted by the complete eye model. Corneal spherical aberration and horizontal coma were compensated by the IOL, and in 58.3% of the cases IOL tilt and decentration contributed to compensation of horizontal coma. We conclude that customized computer eye models are a good representation of real eyes with IOLs and allow understanding of the relative contribution of optical, geometrical and surgically-related factors to image quality. Corneal spherical aberration is reduced by aspheric IOLs, although other corneal high order aberrations are still a major contributor to total aberrations in pseudophakic eyes. Tilt and decentration of the IOLs represent a relatively minor contribution of the overall optical quality of the eye.

  6. Functionalised polysiloxanes as injectable, in situ curable accommodating intraocular lenses.

    Science.gov (United States)

    Hao, Xiaojuan; Jeffery, Justine L; Wilkie, John S; Meijs, Gordon F; Clayton, Anthony B; Watling, Jason D; Ho, Arthur; Fernandez, Viviana; Acosta, Carolina; Yamamoto, Hideo; Aly, Mohamed G M; Parel, Jean-Marie; Hughes, Timothy C

    2010-11-01

    The aged eye's ability to change focus (accommodation) may be restored by replacing the hardened natural lens with a soft gel. Functionalised polysiloxane macromonomers, designed for application as an injectable, in situ curable accommodating intraocular lens (A-IOL), were prepared via a two-step synthesis. Prepolymers were synthesised via ring opening polymerisation (ROP) of octamethylcyclotetrasiloxane (D(4)) and 2,4,6,8-tetramethylcyclotetrasiloxane (D(4)(H)) in toluene using trifluoromethanesulfonic acid (TfOH) as catalyst. Hexaethyldisiloxane (HEDS) was used as the end group to control the molecular weight of the prepolymers, which were then converted to macromonomers by hydrosilylation of the SiH groups with allyl methacrylate (AM) to introduce polymerisable groups. The resulting macromonomers had an injectable consistency and thus, were able to be injected into and refill the empty lens capsular bag. The macromonomers also contained a low ratio of polymerisable groups so that they may be cured on demand, in situ, under irradiation of blue light, in the presence of a photo-initiator, to form a soft polysiloxane gel (an intraocular lens) in the eye. The pre-cure viscosity and post-cure modulus of the polysiloxanes, which are crucial factors for an injectable, in situ curable A-IOL application, were controlled by adjusting the end group and D(4)(H) concentrations, respectively, in the ROP. The macromonomers were fully cured within 5 min under light irradiation, as shown by the rapid change in modulus monitored by photo-rheology. Ex vivo primate lens stretching experiments on an Ex Vivo Accommodation Simulator (EVAS) showed that the polysiloxane gel refilled lenses achieved over 60% of the accommodation amplitude of the natural lens. An in vivo biocompatibility study in rabbits using the lens refilling (Phaco-Ersatz) procedure demonstrated that the soft gels had good biocompatibility with the ocular tissue. The polysiloxane macromonomers meet the targeted

  7. Pathologic comparison of asymmetric or sulcus fixation of 3-piece intraocular lenses with square versus round anterior optic edges.

    Science.gov (United States)

    Ollerton, Andrew; Werner, Liliana; Strenk, Susan; Strenk, Lawrence; Leishman, Lisa; Bodnar, Zachary; Kirk, Kevin R; Michelson, Jennifer; Mamalis, Nick

    2013-08-01

    To evaluate the pathologic findings of 3-piece intraocular lenses (IOLs) with asymmetric or sulcus fixation in pseudophakic cadaver eyes, comparing IOLs with square or round edges on the anterior optic surface. Comparative case series with pathology. A total of 661 pseudophakic cadaver eyes, obtained from eye banks within the United States, implanted with different IOLs. Anterior segment scanning of whole eyes with a high-frequency ultrasound system or high-resolution anterior segment magnetic resonance imaging followed by gross examination. Selected eyes were processed for complete histopathologic analysis. Findings from imaging, gross, and histopathologic evaluation that could be related to out-of-the-bag fixation of the lenses. Of 661 pseudophakic cadaver eyes obtained, 13 had 3-piece hydrophobic acrylic IOLs with anterior and posterior square optic edges, and 14 had 3-piece lenses with anterior round edges (13 silicone lenses and 1 hydrophobic acrylic lens) without symmetric in-the-bag fixation. These 27 selected eyes were processed for complete histopathologic analysis. Gross findings in both groups were composed of IOL decentration and tilt, pigmentary dispersion within the anterior segment and on the IOL surface, and iris transillumination defects. Histopathology of the 14 eyes with 3-piece IOLs with round anterior optic edges showed mild focal disruption of the iris pigmented layer and loop protrusion/erosion in the ciliary sulcus. Additional changes observed in the 13 eyes with square anterior optic edge IOLs included iris changes, such as vacuolization, disruption and loss of the pigmented epithelial layers, iris thinning and atrophy, synechiae, and pigmentary dispersion within the trabecular meshwork. One eye also exhibited initial signs of optic nerve disc cupping. In this series, pathologic findings were more severe in eyes implanted with 3-piece IOLs with square anterior optic edges, suggesting that IOLs with round anterior edges are more suitable for

  8. Implanting two posterior chamber intraocular lenses in a case of microphthalmos.

    Science.gov (United States)

    Gayton, J L; Sanders, V N

    1993-11-01

    A 31-year-old male with bilateral microphthalmos and a history of severe refractive amblyopia presented with early nuclear sclerosis. Intraocular lens calculations determined the patient would need about a 46.0 diopter power intraocular lens in both eyes to achieve satisfactory vision postoperatively. When no manufacturer could or was willing to make such a high-power lens, we chose to implant two lenses in each eye. The patient is satisfied with his postoperative vision and overall outcome.

  9. [Importance of asferic treatment of intraocular lenses in contrast sensitivity of the human eye].

    Science.gov (United States)

    Calţaru, Dana Cristina; Pop, Mihai

    2014-01-01

    Clinical study which follows the influence of asphericity of intraocular lenses on an important parameter of quality of vision in operated cataract patients - contrast sensibility. This is a pilot, prospective study with 131 eyes of 124 patients, which had cataract surgery by phacoemulsification between 2011-2012. All operations were done by the same surgeon. EXCLUSION CRITERIAS WERE: VA ( 0.7; postop refraction >0.75 D sf. or 0.75 D cyl, corneal diseases, optic nerv or retinal pathologies, atypical surgery, pupil diameter 3 mm. Postoperative control was done at six weeks and included : AV, optical correction, contrast sensibility testing, intraocular pressure, posterior pol exam. Contrast sensibility testing was done using a LCD device, in fotopic condition, CC-100 TOPCON. Contrast sensibility graphics were compared between spheric and aspheric lenses for Zeiss, AMO, Bausch&Lomb, Alcon. There were no statistically significant differences between aspherical lenses. Also, there were no differences for the same manufacturer between spherical and aspherical lenses.

  10. Drug loading of foldable commercial intraocular lenses using supercritical impregnation.

    Science.gov (United States)

    Bouledjouidja, A; Masmoudi, Y; Sergent, M; Trivedi, V; Meniai, A; Badens, E

    2016-03-16

    The drug delivery through intraocular lenses (IOLs) allows the combination of cataract surgery act and postoperative treatment in a single procedure. In order to prepare such systems, "clean" supercritical CO2 processes are studied for loading commercial IOLs with ophthalmic drugs. Ciprofloxacin (CIP, an antibiotic) and dexamethasone 21-phosphate disodium (DXP, an anti-inflammatory drug) were impregnated into foldable IOLs made from poly-2-hydroxyethyl methacrylate (P-HEMA). A first pre-treatment step was conducted in order to remove absorbed conditioning physiological solution. Supercritical impregnations were then performed by varying the experimental conditions. In order to obtain transparent IOLs and avoid the appearance of undesirable foaming, it was necessary to couple slow pressurization and depressurization phases during supercritical treatments. The impregnation yields were determined through drug release studies. For both drugs, release studies show deep and reproducible impregnation for different diopters. For the system P-HEMA/CIP, a series of impregnations was performed to delimit the experimental range at two pressures (80 and 200 bar) in the presence or absence of ethanol as a co-solvent for two diopters (+5.0 D and +21.0 D). Increase in pressure in the absence of a co-solvent resulted in improved CIP impregnation. The addition of ethanol (5 mol%) produced impregnation yields comparable to those obtained at 200 bar without co-solvent. A response surface methodology based on experimental designs was used to study the influence of operating conditions on impregnation of IOLs (+21.0 D) in the absence of co-solvent. Two input variables with 5 levels each were considered; the pressure (80-200 bar) and the impregnation duration (30-240 min). CIP impregnation yields ranging between 0.92 and 3.83 μg CIP/mg IOL were obtained from these experiments and response surface indicated the pressure as a key factor in the process. The DXP impregnation in P-HEMA was

  11. Haptic Breakage after Transscleral Fixation of a Single-Piece Acrylic Intraocular Lens

    Directory of Open Access Journals (Sweden)

    Hiroki Tanaka

    2014-07-01

    Full Text Available Purpose: To report the case of a patient with a damaged haptic of an acrylic intraocular lens (IOL after transscleral IOL fixation. Methods: This is a retrospective and descriptive case report. Results: A 40-year-old man presented with sudden visual loss in the left eye. He had undergone phacoemulsification/aspiration and IOL implantation 3 years previously and IOL repositioning with transscleral fixation 2 years before the initial visit. His visual acuity was 0.3 in the left eye due to corneal edema caused by a foreign body, i.e., the severed haptic tip of the single-piece acrylic IOL, which was surgically removed. The IOL itself was tilted and therefore explanted. The surface of the tip of the haptic suggested that the monofilament suture thread had exerted continuous force across the haptic. Conclusions: The haptics of acrylic IOLs can be damaged after transscleral fixation.

  12. Professor Peter Choyce: an early pioneer of intraocular lenses and corneal/refractive surgery.

    Science.gov (United States)

    Pandey, Suresh K; Apple, David J

    2005-06-01

    Professor Peter Choyce, FRCS, DOMS, MS, was one of the pioneers of intraocular lens implant surgery. He developed an interest in artificial lens implantation following cataract surgery, a procedure that was widely criticized by the ophthalmic establishment in the UK, Europe, North America and other countries. Owing to the opposition to the intraocular lenses, Peter Choyce together with Sir Harold Ridley co-founded the International Intraocular Implant Club in 1966, which was responsible for the gradual acceptance of artificial lens implantation. Peter Choyce developed several models of intraocular lens, but did not patent the majority of them. The Choyce Mark IX, manufactured by Rayner Intraocular Lenses, became the first US Food and Drug Administration-approved intraocular lens in 1981. A review of Peter Choyce's record confirms a significant number of original innovations in the field of anterior segment surgery, including many procedures taken for granted today, but not associated with his name. These include early work on both kerato- and intraocular lens-refractive procedures, keratoprosthesis, pioneering paediatric implant procedures and others. Unfortunately his tenacious adherence to anterior chamber lens technology, while in general clinically sound, caused many to question his influence and hence he remained poorly understood even until after his death. He passed away on 8 August 2001 after a long fight with colon cancer. In this article, we provide evidence and elaborate Peter Choyce's accomplishments, which places him as one of the most innovative ophthalmologist in his surgical field in the twentieth century.

  13. Comparison of Biofilm Formation Capacities of Two Clinical Isolates of Staphylococcus Epidermidis with and without icaA and icaD Genes on Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Sertaç Argun Kıvanç

    2017-03-01

    Full Text Available Objectives: To compare biofilm formations of two Staphylococcus epidermidis (S. epidermidis isolates with known biofilm formation capacities on four different intraocular lenses (IOL that have not been studied before. Materials and Methods: Two isolates obtained from ocular surfaces and identified in previous studies and stored at -86 °C in 15% glycerol in the microbiology laboratory of the Anadolu University Department of Biology were purified and used in the study. The isolates were S. epidermidis KA 15.8 (ICA+, a known biofilm producer isolate positive for icaA, icaD and bap genes, and S. epidermidis KA 14.5 (ICA-, known as a non-biofilm producer isolate negative for icaA, icaD and bap genes. The biofilm formation capacities of the 2 isolates on 4 different IOLs were compared. Two of the IOLs were acrylic (UD613 [IOL A], Turkey; SA60AT [IOL B], USA, and the other two were polymethyl methacrylate (PMMA (B60130C [IOL C], India; B55125C [IOL D], India. Bacterial enumeration and optical density measurements were done from biofilms that formed on the IOLs. Biofilms were imaged using scanning electron microscopy. Results: Mean bacterial counts on the IOLs were 7.1±0.4 log10 CFU/mL with the ICA+ isolate, and 6.7±0.8 log10 CFU/mL with the ICA- isolate; there were no statistically significant differences. Biofilm formation was lower with acrylic lenses than PMMA lenses with both isolates (p=0.009 and p=0.013. The highest biofilm production was obtained on IOL C (PMMA (p<0.001 and the lowest was obtained on IOL A (hydrophilic acrylic (p<0.001. Conclusion: Bacterial counts after biofilm formation were lower on acrylic lenses, especially hydrophilic acrylic with hydrophobic properties. Further animal and in vivo studies are required to support the findings of this study.

  14. Clinical comparison of the optical performance of aspheric and spherical intraocular lenses

    NARCIS (Netherlands)

    van Gaalen, Kim W.; Koopmans, Steven A.; Jansonius, Nomdo M.; Kooijman, Aart C.

    2010-01-01

    PURPOSE: To compare the optical performance of aspheric Tecnis ZA9003 and spherical Sensar AR40e intraocular lenses (IOLs). SETTING: Laboratory of Experimental Ophthalmology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands. METHODS: An aspheric IOL was implan

  15. Surface characterization of polymer-drug modified vascular stents and intraocular lenses

    Science.gov (United States)

    Elachchabi, Amin

    human coronary smooth muscle cell growth in vitro whereas dexamethasone exhibited no similar effect. A second major subject of this research was a series of studies concerning the properties of foldable hydrophobic acrylic intraocular lenses (IOLs) which have not previously been investigated. Most IOLs implanted today in the U.S. and the western world are foldable. The goal of this research was to conduct new surface characterization studies on the surfaces of several different foldable lenses in clinical use. Atomic force microscopy showed that these IOLs have different morphologies and that hydration greatly altered the surface morphology of these implants. Contact angle goniometry studies indicated that water contact angles varied significantly from one lens to the other and that prolonged hydration led to a reduction of the water contact angle. Nanoindentation experiments yielded new information on the surface mechanical properties of IOLs and a new methodology was developed to analyze nanoindent data to determine the surface modulus and hardness of foldable IOLs and low modulus polymers in general. The novel surface properties studies reported here can be important in guiding the design and the development of new ocular implants.

  16. A study of patient satisfaction after cataract surgery with implantation of different types of intraocular lenses

    Directory of Open Access Journals (Sweden)

    Wei Ching-Kuo

    2012-10-01

    Full Text Available Abstract Background The implementation of capitated payment has driven medical institutions through developing balance billing for medical services. By exploring the patients’ decision-making factors on different self-pay items, a reference for the pricing and sales strategy for the related products can be formed. The major purposes of this study were to analyze the determinants of preoperative selection and postoperative satisfaction with implantation of different types of intraocular lenses in cataract surgery. Methods This cross-sectional study consisted of 127 patients that were 50 years of age and older, and who had phacoemulsification with intraocular lens implantation in both eyes. Data were collected by using a structured questionnaire. The following parameters were measured: access to medical care, attitude towards receiving medical products at one’s own expense, overall patient satisfaction and postoperative visual clarity. Results The results showed that the patient’s gender, educational level and economic status influenced the type of intraocular lens chosen. Patients in the insurance group cared about access to medical care, and patients in the balance billing group cared about product differentiation. ANOVA results showed no statistically significant differences in the overall satisfaction of the patients among the groups with different types of intraocular lenses. Patients that received cataract surgery with implantation of multifocal intraocular lenses had better vision when trying to view smaller objects and when looking at objects under strong light. Conclusions Manufacturers should increase the number of differences between their products, and health care providers can then recommend the appropriate intraocular lens in accordance with the needs or demands of their patients, and also by keeping in mind the financial constraints of their patients.

  17. Cauterization technique for suture erosion in transscleralfixation of intraocular lenses

    Directory of Open Access Journals (Sweden)

    Xu-Ting Hu

    2013-12-01

    Full Text Available Transscleral suturing is a commonly applied technique to fix intraocular implants in the sulcus. A major problem after transscleral implantation is suture erosion that normally happens in the late post-surgery period and may result in an increased incidence of endophthalmitis. Here we describe an original cauterization method by using a glass rod to melt the exposed suture end without damaging the suture knot in the sclera to avoid suture exposure in sclera-fixed IOL implantation. This is a simple, quick and effective technique that can be performed without conjunctiva incisions and will help to reduce suture erosion related complications.

  18. Evaluation of Different Power of Near Addition in Two Different Multifocal Intraocular Lenses

    Directory of Open Access Journals (Sweden)

    Ugur Unsal

    2016-01-01

    Full Text Available Purpose. To compare near, intermediate, and distance vision and quality of vision, when refractive rotational multifocal intraocular lenses with 3.0 diopters or diffractive multifocal intraocular lenses with 2.5 diopters near addition are implanted. Methods. 41 eyes of 41 patients in whom rotational +3.0 diopters near addition IOLs were implanted and 30 eyes of 30 patients in whom diffractive +2.5 diopters near addition IOLs were implanted after cataract surgery were reviewed. Uncorrected and corrected distance visual acuity, intermediate visual acuity, near visual acuity, and patient satisfaction were evaluated 6 months later. Results. The corrected and uncorrected distance visual acuity were the same between both groups (p=0.50 and p=0.509, resp.. The uncorrected intermediate and corrected intermediate and near vision acuities were better in the +2.5 near vision added intraocular lens implanted group (p=0.049, p=0.005, and p=0.001, resp. and the uncorrected near vision acuity was better in the +3.0 near vision added intraocular lens implanted group (p=0.001. The patient satisfactions of both groups were similar. Conclusion. The +2.5 diopters near addition could be a better choice in younger patients with more distance and intermediate visual requirements (driving, outdoor activities, whereas the + 3.0 diopters should be considered for patients with more near vision correction (reading.

  19. 三种非球面单焦点丙烯酸酯人工晶状体植入术后视觉质量的临床观察%Clinical observation on visual function in patients implanted three kinds of aspheric acrylic monofocal intraocular lenses

    Institute of Scientific and Technical Information of China (English)

    冀海轮; 肖伟; 赵芳; 赵岱新; 濮伟

    2013-01-01

    Objective To evaluate best corrected visual acuity(BCVA) and contrast sensitivity(CS) under photopic condition with no glare in patients following implantation of three different kinds of aspheric acrylic monofocal intraocular lens. Methods 77 cases(90 eyes) of age-related cataract patients were selected,who were undergone phacoemulsification and intraocular lens(IOL) implantation in our hospital during December 2011 to November 2012. Preoperatively, the patients were randomly divided into three groups. Group 1 including 30 eyes(25 cases) were implanted with hydrophobic yellow-tinted acrylic IOLs; Group 2(30 eyes of 28 cases) with hydrophilic acrylic IOLs;Group 3(30 eyes of 24 cases) with hydrophilic acrylic surface heparin processing IOLs. All eyes were evaluated at 1 month and 3 months postoperatively. The BCVA and CS under photopic condition without glare were measured and underwent statistical analysis. Results There was neither statistically significant difference in the BCVA(P>0.05), nor statistically significant difference in contrast sensitivity results (after standardization of contrast sensitivity value: lgCS)(P>0.05) between groups. Conclusions There were not marked differences of BCVA and CS between groups of patients at the follow-up intervals of 1 month and 3 months. The blue-filter type artificial lens protect the retina, thus, it is advisable to implant yellow-tinted filter blue artificial lens.%目的:研究三种非球面丙烯酸酯人工晶状体植入术后患者在最佳矫正视力及明视下对比敏感度(contrast sensitivity,CS)的变化,评价白内障超声乳化联合单焦点非球面丙烯酸酯人工晶状体植入术后患者的视觉质量。方法选择2011年12月至2012年11月期间于我院行白内障超声乳化吸除联合人工晶状体植入术的年龄相关性白内障患者77例(90眼)。术前将患者随机分成三组:A组(25例,30眼)植入疏水性染黄色

  20. Calcification of a hydrophilic acrylic intraocular lens: case report with laboratory analysis.

    Science.gov (United States)

    Bodnar, Z M; Rozot, P; Leishman, L; Ollerton, A; Michelson, J; Plasse-Fauque, S; Werner, L

    2013-09-01

    We analyzed a single-piece plate-type hydrophilic acrylic posterior chamber intraocular lens (IOL) that was explanted due to a progressive loss of vision, which occurred 6 years after uncomplicated phacoemulsification. Gross and light microscopy, as well as anterior segment optical coherence tomography (OCT) revealed granular deposits below the IOL surface. Light scattering, as measured with Scheimpflug photography and densitometry analyses was found to be increased; spectrophotometry demonstrated a decrease in the light transmittance of the explanted lens. The granular deposits within the IOL material were found to be composed of calcium by histochemical methods (alizarin red and Von Kossa stains). To our knowledge this is the only report of calcification of this IOL design. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  1. Sulcus Fixation of Foldable Intraocular Lenses Guided by Ultrasound Biomicroscopy.

    Science.gov (United States)

    Gao, Shasha; Qin, Tingyu; Wang, Shengnan; Lu, Yong

    2015-01-01

    Background. To evaluate the clinical efficacy of suture fixation of foldable intraocular lens (IOL) in ciliary sulcus guided by ultrasound biomicroscopy (UBM). Methods. Thirty-five eyes of 32 cases needing suture fixation of foldable IOL in ciliary sulcus in our hospital were collected and divided into two groups: group A and group B. In group A, UBM was performed on 19 eyes of 17 cases before surgery to locate the projection position of ciliary sulcus in iris surface. In group B, the traditional sulcus fixation of IOL was performed on 16 eyes of 15 cases. The inserting position of needles, the haptics position of IOL and the IOL tilt, and decentration were observed by UBM examination 3 months after the surgery. Meanwhile, the vision and contrast sensitivity were analysed. Results. The differences in inserting position of the needle, the IOL tilt and decentration, the ratio of IOL haptics in sulcus, and uncorrected visual acuity were statistically significant (P 0.05). Conclusions. Sulcus fixation of foldable IOL aided by UBM can increase the accuracy of IOL haptics implanted into ciliary sulcus and reduce the IOL tilt and decentration.

  2. Sulcus Fixation of Foldable Intraocular Lenses Guided by Ultrasound Biomicroscopy

    Directory of Open Access Journals (Sweden)

    Shasha Gao

    2015-01-01

    Full Text Available Background. To evaluate the clinical efficacy of suture fixation of foldable intraocular lens (IOL in ciliary sulcus guided by ultrasound biomicroscopy (UBM. Methods. Thirty-five eyes of 32 cases needing suture fixation of foldable IOL in ciliary sulcus in our hospital were collected and divided into two groups: group A and group B. In group A, UBM was performed on 19 eyes of 17 cases before surgery to locate the projection position of ciliary sulcus in iris surface. In group B, the traditional sulcus fixation of IOL was performed on 16 eyes of 15 cases. The inserting position of needles, the haptics position of IOL and the IOL tilt, and decentration were observed by UBM examination 3 months after the surgery. Meanwhile, the vision and contrast sensitivity were analysed. Results. The differences in inserting position of the needle, the IOL tilt and decentration, the ratio of IOL haptics in sulcus, and uncorrected visual acuity were statistically significant (P0.05. Conclusions. Sulcus fixation of foldable IOL aided by UBM can increase the accuracy of IOL haptics implanted into ciliary sulcus and reduce the IOL tilt and decentration.

  3. Two-photon absorption induced drug delivery from polymeric intraocular lenses

    Science.gov (United States)

    Hampp, Norbert A.; Kim, Hee-Cheol; Kreiling, Stefan; Hesse, Lutz; Greiner, Andreas

    2003-10-01

    Secondary cataracts are quite often observed after implantation of polymeric intraocular lenses. The reason for this complication is that lens epithelial cells remain in the capsular bag when the natural lens is removed. They begin proliferation and cause secondary cataracts. It is not desireable to add cell toxic agents at the time of the implantation because wound healing is negatively affected. We have developed polymeric intraocular lenses which are equipped with a drug depot which may be released non-invasively through photochemical treatment. In the example presented the drug is 5-fluoruracil (5FU) which is covalently bound to the polymer. Deliberation of 5FU from the polymer is done photochemically. Since light is transmitted permanently through the artificial intraocular lens and wearing of special glasses by the patient should be omitted conventional photochemistry is not a suitable tool for the drug release. The polymer-5FU linkage is designed in a way that it has a high two-photon absorption cross-section. Two-photon absorption is used to selectively release 5FU from the lens. The one-photon reaction is blocked since the cornea does absorb UV light. The principle shown here is not limited to 5FU but may be applied to other drugs also.

  4. Hydrophilic Acrylic Intraocular Lens Opacification after Descemet Stripping Automated Endothelial Keratoplasty

    Science.gov (United States)

    Norouzpour, Amir; Zarei-Ghanavati, Siamak

    2016-01-01

    Purpose: To report hydrophilic acylic intraocular lens (IOL) opacification after Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) in an eye with multiple prior intraocular surgeries and iatrogenic aniridia. Case Report: A 34-year-old woman with history of penetrating keratoplasty (PKP) for advanced keratoconus and subsequent Urrets-Zavalia Syndrome (UZS) underwent phacoemulsification and hydrophilic acrylic IOL implantation for her cataract. In order to control post-PKP glaucoma, multiple glaucoma surgeries including two glaucoma drainage implants were performed. As the original corneal graft failed, the patient subsequently underwent re-PKP. Four years later, she underwent DSAEK for treatment of the second graft failure. Ten months after DSAEK, a double semi-circular pattern of IOL opacification was observed on the anterior surface of the IOL. The patient did not report any complaints and we decided not to exchange the IOL. Conclusion: In an eye with UZS and iatrogenic aniridia, IOL opacification may result from direct contact between the IOL surface and exogenous air. Aniridia can be a risk factor for development of IOL opacification after DSAEK. Further studies are required to confirm this hypothesis. PMID:27413506

  5. Residual aniseikonia among patients fitted with one or two intraocular lenses (pseudophakic corrections)

    Science.gov (United States)

    Lakshminarayanan, V; Enoch, J M; Knowles, R A

    1993-02-01

    In the presence of one or two intraocular lenses (IOL's; pseudophakic corrections) or in the presence of naturally occurring or developmental anisometropia (due to a tumescent cataract) some induced or residual refractive aniseikonia is usually encountered. We wish to call this problem to the attention of the optometric practitioner. We provide a discussion of the resultant aniseikonia and simple rules of thumb for management of such patients with refractive aniseikonia. Aniseikonia in these patients may be less important than once had been suggested, but certainly it is more significant than it is currently being considered. Use of personal computers to calculate this aniseikonia makes appropriate correction relatively easy and readily applicable.

  6. Influence of ocular longitudinal chromatic aberration on the selection of aspheric intraocular lenses.

    Science.gov (United States)

    Hong, Xin; Choi, Myoung

    2010-12-06

    Polychromatic defocus could affect the optimal residual spherical aberration that could yield the best image quality for patients with intraocular lenses (IOLs). Modulation transfer functions (MTFs) were generated using a model that included polychromatic defocus. The maximum MTF volume occurred at + 0.05 μm of overall ocular spherical aberration. For 3 case studies, the optimal overall ocular spherical aberration was ~0.05 μm more positive with the contribution of polychromatic defocus than without it. Overall, the model indicated that image quality was usually best when IOLs allowed overall ocular spherical aberration that was slightly positive, rather than strongly positive, zero, or negative.

  7. Toric Intraocular Lenses in the Correction of Astigmatism During Cataract Surgery

    DEFF Research Database (Denmark)

    Kessel, Line; Andresen, Jens; Tendal, Britta

    2016-01-01

    TOPIC: We performed a systematic review and meta-analysis to evaluate the benefit and harms associated with implantation of toric intraocular lenses (IOLs) during cataract surgery. Outcomes were postoperative uncorrected distance visual acuity (UCDVA) and distance spectacle independence. Harms were...... literature search in the Embase, PubMed, and CENTRAL databases within the Cochrane Library. We included randomized clinical trials (RCTs) if they compared toric with non-toric IOL implantation (± relaxing incision) in patients with regular corneal astigmatism and age-related cataracts. We assessed the risk...

  8. Prevention of capsular bag opacification with a modified hydrophilic acrylic disk-shaped intraocular lens.

    Science.gov (United States)

    Leishman, Lisa; Werner, Liliana; Bodnar, Zachary; Ollerton, Andrew; Michelson, Jennifer; Schmutz, Mason; Mamalis, Nick

    2012-09-01

    To evaluate the stability and capsular bag opacification with a modified disk-shaped 1-piece hydrophilic acrylic intraocular lens (IOL) suspended between 2 complete haptic rings connected by a pillar of the haptic material and with a commercially available 1-piece hydrophilic acrylic IOL. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Study and control IOLs were implanted into the left eyes and right eyes of 5 New Zealand rabbits. Eyes were examined at the slitlamp from 1 through 4 weeks. At 4 weeks, the globes were enucleated and evaluated under a very-high-frequency ultrasound. Photographs were taken and capsular bag opacification scored from the posterior aspect (Miyake-Apple view), and the eyes were processed for complete histopathology. At 4 weeks, the posterior capsule opacification score was 0.0 in the study group and 1.75 ± 0.5 (SD) in the control group (P=.005, paired t test). Ultrasound examination showed that 2 of the study IOLs had no contact between the posterior optic surface and the posterior capsule. Minimal proliferative cortical material was confined to the peripheral space between anterior and posterior rings of the study IOL haptics in localized areas at the equatorial region of the capsular bag. Anterior capsule opacification was absent in all eyes. The study IOL is a modification of a previous design, incorporating haptic perforations between the peripheral rings. By maintaining an open capsular bag and enhancing endocapsular inflow of aqueous, this modified design appears to prevent capsular bag opacification. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  9. Causes and correction of dissatisfaction after implantation of presbyopia-correcting intraocular lenses

    Directory of Open Access Journals (Sweden)

    Gibbons A

    2016-10-01

    Full Text Available Allister Gibbons, Tayyeba K Ali, Daniel P Waren, Kendall E Donaldson Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA Purpose: The purpose of this study was to assess the causes and possible solutions for patient dissatisfaction after the implantation of presbyopia-correcting intraocular lenses (IOLs. Methods: This study was a retrospective review of clinical records. All patients who were seen between January 2009 and December 2013 whose primary reason for consultation was dissatisfaction with visual performance after presbyopia-correcting IOL implantation were included in the study. A single treating physician, who determined the most probable cause of dissatisfaction, decided which interventions to pursue following the initial consultation. Results: Data from 74 eyes of 49 patients were analyzed. The most common cause for complaint was blurry or foggy vision both for distance and near (68%. Complaints were most frequently attributed to residual refractive error (57% and dry eye (35%. The most common interventions pursued were treatment of refractive error with glasses or contact lenses (46% and treatment for dry eye (24%. Corneal laser vision correction was done in 8% of eyes; 7% required an IOL exchange. After the interventions, 45% of patients had completed resolution of symptoms, 23% of patients were partially satisfied with the results, and 32% remained completely dissatisfied with the final results. Conclusion: The most identifiable causes of dissatisfaction after presbyopia-correcting IOL implantation are residual refractive error and dry eye. Most patients can be managed with conservative treatment, though a significant number of patients remained unsatisfied despite multiple measures. Keywords: intraocular lens, cataract, presbyopia, multifocal intraocular lens

  10. Microscopic analysis of an opacified OFT CRYL® hydrophilic acrylic intraocular lens

    Directory of Open Access Journals (Sweden)

    Bruna Vieira Ventura

    Full Text Available ABSTRACT A 51-year-old patient underwent posterior vitrectomy with perfluoropropane gas injection, phacoemulsification, and implantation of an Oft Cryl® hydrophilic acrylic intraocular lens (IOL because of traumatic retinal detachment and cataract in the right eye. On the first postoperative day, gas was filling the anterior chamber because of patient's non-compliance in terms of head positioning, and was reabsorbed within one week. Eight months later, the patient returned complaining of a significant decrease in vision. IOL opacification was noticed by slit-lamp examination. The lens was explanted to undergo gross and light microscopic analysis. The lens was also stained with the alizarin red method for calcium identification. Light microscopic analysis confirmed the presence of granular deposits, densely distributed in an overall circular pattern in the central part of the lens optic. The granules stained positive for calcium. This is the first case of the opacification of this type of hydrophilic lens. Surgeons should be aware of this potential postoperative complication, and the use of hydrophilic IOLs should be avoided in procedures involving intracameral gas because of the risk of IOL opacification.

  11. Calcium-phosphate deposits on a hydrophilic acrylic intraocular lens after silicon oil tamponade

    Directory of Open Access Journals (Sweden)

    Rashid Alsaeidi

    2008-01-01

    Full Text Available We report a 52-year-old man who underwent uncomplicated cataract operation and posterior chamber lens implantation (hydrophilic acrylic lens in his left eye 5 years prior to presentation. Two years after surgery he developed pseudophakic retinal detachment which was successfully treated with pars plana vitrectomy and silicon oil tamponade. The silicon oil was removed one year after surgery. A year later he complained of increasing blurred vision in the left eye. Clinical examination revealed vesicular alterations located superficially on the intraocular lens (IOL, which could not be removed by perflourocarbon-perflourohexloctane lavage. As the patient complained about increasing visual impairment, the IOL was removed. The IOL was investigated by electronmicroscopy and biochemical analysis. During electron microscopy and following biochemical analysis the observed alterations were identified as calcium-phosphate particles located on the superficial aspect of the IOL. The occurrence of calcium-phosphate deposits on a posterior chamber IOL after silicon oil tamponade is a rare complication and has not been described so far. As these deposits interfere with visual acuity, removal of the lens has to be considered.

  12. Microscopic analysis of an opacified OFT CRYL® hydrophilic acrylic intraocular lens.

    Science.gov (United States)

    Ventura, Bruna Vieira; MacLean, Kyle Douglas; Lira, Wagner; Oliveira, Daniele Mendes de; Ventura, Camila Vieira; Werner, Liliana

    2016-01-01

    A 51-year-old patient underwent posterior vitrectomy with perfluoropropane gas injection, phacoemulsification, and implantation of an Oft Cryl® hydrophilic acrylic intraocular lens (IOL) because of traumatic retinal detachment and cataract in the right eye. On the first postoperative day, gas was filling the anterior chamber because of patient's non-compliance in terms of head positioning, and was reabsorbed within one week. Eight months later, the patient returned complaining of a significant decrease in vision. IOL opacification was noticed by slit-lamp examination. The lens was explanted to undergo gross and light microscopic analysis. The lens was also stained with the alizarin red method for calcium identification. Light microscopic analysis confirmed the presence of granular deposits, densely distributed in an overall circular pattern in the central part of the lens optic. The granules stained positive for calcium. This is the first case of the opacification of this type of hydrophilic lens. Surgeons should be aware of this potential postoperative complication, and the use of hydrophilic IOLs should be avoided in procedures involving intracameral gas because of the risk of IOL opacification.

  13. Interlenticular opacification: clinicopathological correlation of a complication of posterior chamber piggyback intraocular lenses.

    Science.gov (United States)

    Gayton, J L; Apple, D J; Peng, Q; Visessook, N; Sanders, V; Werner, L; Pandey, S K; Escobar-Gomez, M; Hoddinott, D S; Van Der Karr, M

    2000-03-01

    To present a clinicopathological correlation of 2 pairs of piggyback posterior chamber intraocular lenses (PC IOLs) explanted because of opacification between the lens optics. Gayton Health Center, Eyesight Associates of Middle Georgia, Warner Robins, Georgia, and Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. Two pairs of piggyback AcrySof lenses were explanted from 2 patients with significant visual loss related to opacification between the optics. They were submitted for pathological analysis. Gross and histopathological examinations were performed, and photomicroscopy was used to document the results. Gross examination showed accumulation of a membrane-like white material between the lenses. Histopathological examination revealed that the tissue consisted of retained/proliferative lens epithelial cells (bladder cells or pearls) mixed with lens cortical material. Piggyback PC IOLs were explanted in 2 cases because of a newly described complication, interlenticular opacification. Three surgical means may help prevent this complication: meticulous cortical cleanup, especially in the equatorial region; creation of a relatively large continuous curvilinear capsulorhexis to sequester retained cells peripheral to the IOL optic within the equatorial fornix; insertion of the posterior IOL in the capsular bag and the anterior IOL in the ciliary sulcus to isolate retained cells from the interlenticular space.

  14. Higher order aberration comparison between two aspherical intraocular lenses: MC6125AS and Akreos advanced optics

    Institute of Scientific and Technical Information of China (English)

    Mohammad; Taher; Rajabi; Sara; Korouji; Mahgol; Farjadnia; Mohammad; Naderan; Mohammad; Bagher; Rajabi; Bahram; Khosravi; Seyed; Mehdi; Tabatabaie

    2015-01-01

    AIM: To compare higher order aberrations in two aspherical intraocular lenses(IOLs): Akreos advanced optics(AO) and Dr. Schmidt Microcrystalline 6125 aspheric anterior surface(MC6125AS) with each other. METHODS: Forty eyes of 39 patients underwent phacoemulsification and Akreos AO and MC6125 AS were implanted in their eyes in a random manner. Three months post-operatively, higher order aberrations including spherical aberration, coma aberration, and total aberrations were measured and compared.RESULTS: The total aberration was 0.24±0.17 in eyes with Dr. Schmidt and 0.20 ±0.01 in eyes with Akreos AO(P =0.361). The mean of coma aberration was 0.17 ±0.21 and 0.09 ±0.86 in Dr. Schmidt and Akreos lenses,respectively(P =0.825). Total spherical aberration was almost the same in both groups(mean: 0.05, P =0.933).Best corrected visual acuity in Akreos AO(0.10±0.68) and Dr. Schmidt(0.09±0.67) did not differ significantly(P =0.700). CONCLUSION: There is no statistically significant difference in the higher order aberrations between these two aspherical lenses.

  15. Comparison of Through-Focus Image Quality Across Five Presbyopia-Correcting Intraocular Lenses (An American Ophthalmological Society Thesis)

    Science.gov (United States)

    Pepose, Jay S.; Wang, Daozhi; Altmann, Griffith E.

    2011-01-01

    Purpose To assess through-focus polychromatic image sharpness of five US Food and Drug Administration–approved presbyopia-correcting intraocular lenses (IOLs) through a range of object vergences and pupil diameters utilizing an image sharpness algorithm. Methods A 1951 US Air Force resolution target was imaged through a Crystalens AO (AO) (Bausch & Lomb Surgical, Aliso Viejo, California), Crystalens HD (HD) (Bausch & Lomb Surgical, Aliso Viejo, California), aspheric ReSTOR +4.0 (R4) (Alcon Laboratories, Fort Worth, Texas), aspheric ReSTOR +3.0 (R3) (Alcon Laboratories, Fort Worth, Texas), and Tecnis Multifocal Acrylic (TMF) (Abbott Medical Optics, Irvine, California) IOL in an anatomically and optically accurate model eye and captured digitally for each combination of pupil diameter and object vergence. The sharpness of each digital image was objectively scored using a two-dimensional gradient function. Results The AO lens had the best distance image sharpness for all pupil diameters, followed by the HD. With a 5-mm pupil, the R4 lens achieved distance image quality similar to the HD, but inferior to the AO. The R3 successfully moved the near focal point farther from the patient compared to the R4, but did not improve image sharpness at intermediate distances and showed worse distance and near image sharpness. Consistent with apodization, the ReSTOR IOLs displayed better distance and poorer near image sharpness as pupil diameter increased. The TMF lens showed consistent distance and near image sharpness across pupil diameters and exhibited the best near image sharpness for all pupil diameters. Conclusions Differing IOL design strategies to increase depth of field are associated with quantifiable differences in image sharpness at varying vergences and pupil sizes. An objective comparison of the imaging properties of specific presbyopia-correcting IOLs, in conjunction with patients’ pupil sizes, can be useful in selecting the most appropriate IOL for each patient

  16. Location and composition of haptics of posterior chamber intraocular lenses. Histopathologic study of postmortem eyes.

    Science.gov (United States)

    McDonnell, P J; Champion, R; Green, W R

    1987-02-01

    Of 110 eyes with posterior chamber intraocular lenses (IOLs) examined postmortem, 37% had both haptics outside of the capsular bag; 57% had one haptic in the capsular bag and the other haptic outside of the bag. Typically, these optics were decentered by 1 to 2 mm. Only six eyes (5%) had both haptics within the capsular bag. Erosion into the ciliary sulcus produced obliteration of the major arterial circle of the iris in 12 eyes (11%). The local tissue response to eroding haptics was similar for haptics composed of polypropylene and haptics composed of polymethylmethacrylate (PMMA). The authors found considerable discrepancy between the actual location of haptics and the surgeon's desired location (i.e., capsular bag or ciliary sulcus). Most of these cases were clinically successful.

  17. Surface modification of polymethyl methacrylate intraocular lenses by plasma for improvement of antithrombogenicity and transmittance

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lihua; Wu Di; Chen Yashao; Wang Xiaoli; Zhao Guowei; Wan Haiyan [Key Laboratory of Applied Surface and Colloid Chemistry (Shaanxi Normal University), Ministry of Education, School of Chemistry and Materials Science, Chang' an South Road 199, Xi' an 710062 (China); Huang Changzheng [Able Eye Device Co. Ltd, Zhengzhou 450008 (China)

    2009-05-15

    To improve antithrombogenicity and reduce ultraviolet transmittance, polymethyl methacrylate intraocular lenses (PMMA IOLs) were pretreated with Ar plasma and combined with heparin (Hp), with polyglycol (PEG) and with both Hp and PEG in a plasma atmosphere. The resulting modified PMMA IOLs denoted as PEG-PMMA, Hp-PMMA and Hp-PEG-PMMA were characterized by attenuated total reflectance Fourier transfer infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), ultraviolet-visible spectroscopy (UV-vis), contact angle (CA) and platelet adhesion experiments. The results indicated that Hp and PEG had been successfully immobilized onto the surfaces of PMMA IOLs. Antithrombogenicity was improved remarkably and ultraviolet transmittance was reduced as well.

  18. One Year Follow-Up After Veriflex Phakic Intraocular Lenses Implantation for Correction of Myopia

    Science.gov (United States)

    Pjano, Melisa Ahmedbegovic; Biscevic, Alma; Grisevic, Senad; Pidro, Ajla; Ratkovic, Mirko; Bohac, Maja; Husovic, Amila Alikadic; Gojak, Refet

    2016-01-01

    Objectives: The aim of this study was to evaluate visual and refractive outcomes after Veriflex phakic intraocular lenses (pIOL) implantation in moderately myopic eyes as well as postoperative complications. Methods: This prospective clinical study included 40 eyes of 26 patients which underwent implantation of Veriflex for correction of myopia from -6.00 to -14.50 diopters (D) in the Eye Clinic Svjetlost Sarajevo, from January 2011 to January 2014. Uncorrected distance visual acuity (UDVA), manifest residual spherical equivalent (MRSE), intraocular pressure (IOP), endothelial cell (EC) density were evaluated at one, three, six and 12 months. Other complications in postoperative period were evaluated. For statistical analysis SPSS for Windows and Microsoft Excel were used. Results: Out of 26 patients 14 had binocular and 12 monocular procedure, with mean age of 29.8±6.5 years. After 12 months mean UDVA was 0.73±0.20. Mean MRSE was -0.39±0.31D and 90% of eyes had MRSE within ±1D. EC loss was 7.18±4.33%. There was no significant change of IOP by the end of 12 months follow up period. The only intraoperative complication was hyphema and occurred in one eye. Few postoperative complications were: subclinical inflammation in three eyes (7,5%), pigment dispersion in four eyes (10%), ovalisation of papilla in 2 eyes (5%) and decentration of pIOL in 2 eyes (5%). Conclusion: Implantation of iris-claw phakic lenses Veriflex for treating moderately high myopia is a procedure with good visual and refractive results and few postoperative complications. PMID:27482131

  19. Wavefront analysis and modulation transfer function of three multifocal intraocular lenses

    Directory of Open Access Journals (Sweden)

    Santhiago Marcony

    2010-01-01

    Full Text Available Purpose: To evaluate wavefront performance and modulation transfer function (MTF in the human eye after the implantation of diffractive or refractive multifocal intraocular lenses (IOLs. Materials and Methods: This was a prospective, interventional, comparative, nonrandomized clinical study. Uncorrected distance and near visual acuity, and wavefront analysis including MTF curves (iTrace aberrometer, Tracey Technologies, Houston, TX, USA were measured in 60 patients after bilateral IOL implantation with 6 months of follow-up. Forty eyes received the diffractive ReSTOR (Alcon, 40 eyes received the refractive ReZoom (Advanced Medical Optics and 40 eyes, the Tecnis ZM900 (Advanced Medical Optics. The comparison of MTF and aberration between the intraocular lenses was performed using analysis of variance (ANOVA, followed by the Dunn test when necessary. Results: The mean uncorrected distance visual acuity was similar in all three groups of multifocal IOLs. The ReSTOR group provided better uncorrected near visual acuity than the ReZoom group ( P < 0.001, but similar to the Tecnis group. Spherical aberration was significantly higher in the ReZoom group ( P = 0.007. Similar MTF curves were found for the aspheric multifocal IOL Tecnis and the spheric multifocal IOL ReSTOR, and both performed better than the multifocal IOL ReZoom in a 5 mm pupil ( P < 0.001 at all spatial frequencies. Conclusions: Diffractive IOLs studied presented similar MTF curves for a 5 mm pupil diameter. Both diffractive IOLs showed similar spherical aberration, which was significantly better with the full-diffractive IOL Tecnis than with the refractive IOL ReZoom.

  20. The Relation of the Location of Haptics of Posterior Chamber Intraocular Lenses and Peripheral Anterior Synechia

    Institute of Scientific and Technical Information of China (English)

    RuiduanLiao; ShaozhenLi

    1995-01-01

    Purpose:To investigate the occurrence,outcome and influencial factors of the pe-ripheral anterior synechia(PAS)following implantation of posterior chamber in-traocular lenses for finding a way to reduce thePAS.Subjects;40 eyes of 38senile cataract patients with normal chamber angle and in-traocular pressue(IOP)preoperatively were examined.Methods:Extracapsular cataract extraction was performed under microscope with insertion of a posterior chamber lens implant vaulted anteriorly by 10°.Go-nioscopy and slit-lamp examination and photography of the operated eyes were performed 3to 6months postoperatively.Results:PAS were found in 20(50%)of the 40eyes.Among the 20eyes with PAS the locations of 23haptics in17eyes corresponded with those of the PAS.PAS were seen more frequently with vertically sulcus-fixated haptics than with the horizontally capsular-fixated haptics.showing a significant difference(P<0.05).88%of the eyes withPAS had pupillary edformation,but their visual acuities and IOP were not affected.Conclusions:PAS is more likely to occur with vertically sulcus-fixated IOL.Rotat-ing the capsular-fixated haptics to the horizontal position may reduce the inci-dence of PAS.Gonioscopy should be a routine follow-up examination.

  1. Causes and correction of dissatisfaction after implantation of presbyopia-correcting intraocular lenses

    Science.gov (United States)

    Gibbons, Allister; Ali, Tayyeba K; Waren, Daniel P; Donaldson, Kendall E

    2016-01-01

    Purpose The purpose of this study was to assess the causes and possible solutions for patient dissatisfaction after the implantation of presbyopia-correcting intraocular lenses (IOLs). Methods This study was a retrospective review of clinical records. All patients who were seen between January 2009 and December 2013 whose primary reason for consultation was dissatisfaction with visual performance after presbyopia-correcting IOL implantation were included in the study. A single treating physician, who determined the most probable cause of dissatisfaction, decided which interventions to pursue following the initial consultation. Results Data from 74 eyes of 49 patients were analyzed. The most common cause for complaint was blurry or foggy vision both for distance and near (68%). Complaints were most frequently attributed to residual refractive error (57%) and dry eye (35%). The most common interventions pursued were treatment of refractive error with glasses or contact lenses (46%) and treatment for dry eye (24%). Corneal laser vision correction was done in 8% of eyes; 7% required an IOL exchange. After the interventions, 45% of patients had completed resolution of symptoms, 23% of patients were partially satisfied with the results, and 32% remained completely dissatisfied with the final results. Conclusion The most identifiable causes of dissatisfaction after presbyopia-correcting IOL implantation are residual refractive error and dry eye. Most patients can be managed with conservative treatment, though a significant number of patients remained unsatisfied despite multiple measures. PMID:27784985

  2. Charles F. Prentice award lecture 2008: surgical correction of presbyopia with intraocular lenses designed to accommodate.

    Science.gov (United States)

    Schor, Clifton M

    2009-09-01

    Surgical restoration of accommodation with accommodating intra-ocular lenses (A-IOLs) presents a complex set of problems involving the design of the prosthetic mechanism. A variety of designs are currently employed that either translate the A-IOL toward the cornea along the sagittal axis, shear two lens components laterally, or deform lens shape to change dioptric power of the eye during attempts to accommodate. Effective biomechanical properties (elasticity and viscosity) of these lenses depend on both material properties and structural design of the A-IOL. Inevitable mismatches between the neuromuscular control of accommodation and the effective biomechanical properties of the prosthetic lens could lead to either unstable oscillations or sluggishness of dynamic accommodation; however, optimal dynamic responses may possibly be restored by neural recalibration. A model of dynamic accommodation is used to predict the consequences of these mismatches on dynamic accommodation, and reverse engineering is used to test the feasibility of neuromuscular recalibration. Empirical measures verify that neuromuscular adaptation of dynamic accommodation is possible in response to optically simulated increases and decreases of ocular-lens stiffness. Other design issues for A-IOLs include stability of optical properties, aberrations and image quality, and interactions of restored accommodation with binocular eye alignment (the near response).

  3. [Intraocular lenses for the correction of refraction errors. Part II. Phakic posterior chamber lenses and refractive lens exchange with posterior chamber lens implantation].

    Science.gov (United States)

    Kohnen, T; Kasper, T; Terzi, E

    2005-11-01

    In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses which are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for posterior chamber lenses these are mainly cataract formation and pigment dispersion. RLE is preferable in cases of high ametropia in which the natural lens has lost its accommodative effect. The main complications for myopic RLA include retinal detachment, while hyperopic refractive lens exchange may be associated with surgical problems in the narrower anterior eye segment.

  4. [Optimisation of the visualisation technique for optical paths through intraocular lenses for characterisation of multifocal imaging properties of Fresnel-zone plates].

    Science.gov (United States)

    Reiß, S; Forbrig, J; Guthoff, R F; Terwee, T; Stolz, H; Siewert, S; El-Tamer, A; Hinze, U; Chichkov, B N; Stachs, O

    2014-12-01

    The utilisation of the diffractive properties of Fresnel zone plates offers the possibility of intraocular lens designs with multiple foci. Such intraocular lenses can be manufactured by two-photon polymerisation (2PP). This paper explains the underlying concept and shows the principles for visualisation of the focus properties of such implants.

  5. The effect of blue-blocking and neutral intraocular lenses on circadian photoentrainment and sleep one year after cataract surgery

    DEFF Research Database (Denmark)

    Brøndsted, Adam Elias; Haargaard, Birgitte; Sander, Birgit;

    2017-01-01

    PURPOSE: To compare the long-term effect on circadian photoentrainment and sleep in patients implanted with neutral and blue-blocking intraocular lenses 1 year after cataract surgery. METHODS: Randomized, controlled trial involving 67 patients with age-related cataract. Intervention was cataract...... compared with neutral IOLs. Cataract surgery improved the response of ipRGCs and sleep quality. However, the effect of cataract surgery on sleep quality may be unrelated to circadian photoentrainment....

  6. Incidência de opacificação de cápsula posterior em pacientes submetidos à facoemulsificação e implante de lentes intra-oculares acrílicas hidrofílicas expansíveis Incidence of posterior capsule opacification in patients submitted to phacoemulsification and expandable acrylic intraocular lens implantation

    Directory of Open Access Journals (Sweden)

    Hilton Arcoverde Gonçalves de Medeiros

    2006-06-01

    Full Text Available OBJETIVO: Avaliar prospectivamente os resultados das lentes intra-oculares de polímeros expansíveis implantadas em pacientes submetidos à facoemulsificação, quanto à incidência de opacificação de cápsula posterior, levando em consideração a biocompatibilidade das lentes expansíveis. MÉTODOS: O grupo de estudo foi composto por 830 pacientes, 1.200 olhos, que foram submetidos a facoemulsificação, utilizando a mesma técnica, variando-se apenas o diâmetro da capsulorrexe, pelo mesmo cirurgião, no período de 1998 a 2002, com implante de lente intra-ocular hidrofílica expansível. O acompanhamento médio foi de 2,4 anos, variando de seis meses a quatro anos. RESULTADOS: O número total de opacificação de cápsula posterior foi de 54 casos. CONCLUSÃO: A incidência de opacificação de cápsula posterior encontrada no grupo foi de 4,6%.PURPOSE: To evaluate prospectively the results of expandable acrylic intraocular lenses in patients submitted to phacoemulsification as regard posterior capsule opacification. METHODS: The study group consisted of 830 patients, 1,200 eyes that underwent phacoemulsification from 1998 to 2002, by the same surgeon, using the same technique but with different diameters of capsulorrhexis, with expandable hydrophilic acrylic intraocular lens implantation. The mean follow-up was 2.4 years, ranging from 6 months to 4 years. RESULTS: The total number of posterior capsule opacification was 54 cases. CONCLUSIONS: The incidence of posterior capsule opacification was 4.6% in these patients.

  7. Prótese intra-ocular de resina acrílica em cães e gatos Acrylic resin intraocular prosthesis in dogs and cats

    Directory of Open Access Journals (Sweden)

    S.C. Rahal

    2000-08-01

    Full Text Available Foram atendidos no Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Unesp - Campus de Botucatu, 11 animais (oito cães e três gatos, com alterações oftálmicas unilaterais graves que levaram à perda total da função ocular (protrusão de globo com injúria nervosa e estrutural, perfurações de córnea com perda de conteúdo intra-ocular e endoftalmites, entre outras. Os animais, com idades entre dois meses e 10 anos, foram submetidos à evisceração e posterior inclusão de esfera de resina acrílica (metilmetacrilato na capa córneo-escleral ou escleral. As esferas foram previamente confeccionadas e esterilizadas por autoclavagem. No pós-operatório foram utilizados antiinflamatórios e antibioticoterapia tópica combinada ou não a sistêmica. O período de observação variou de 2 meses a 3 anos e os aspectos avaliados foram secreção ocular, blefarospasmo, sinais de desconforto e estética. Obtiveram-se resultados satisfatórios em oito casos. Concluiu-se que a resina acrílica pode ser uma alternativa para uso como inclusão em cavidade anoftálmica.Eleven animals (eight dogs and three cats, aged between two months and ten years were referred to the Veterinary Hospital of Faculty of Veterinary Medicine and Animal Science - Unesp, Botucatu, Brazil. These animals presented severe unilateral ophthalmic changes that lead to a total loss of ocular function, such as prolapsed eyes with nervous and structural injury, corneal damage with loss of intraocular contents or endophthalmitis among others. They were submitted to evisceration followed by the insertion of an acrylic resin prosthesis (methylmethacrylate in the corneoscleral or scleral shell. The spheres were previously made and sterilized by autoclave. The postoperative medical therapy included topical and systemic broad-spectrum antibiotics for seven days and anti-inflammatory drugs. The follow-up time varied from two months to three years. The evaluated

  8. An investigation of the effect of silicone oil on polymer intraocular lenses by means of PALS, FT-IR and Raman spectroscopies

    Science.gov (United States)

    Chamerski, Kordian; Lesniak, Magdalena; Sitarz, Maciej; Stopa, Marcin; Filipecki, Jacek

    2016-10-01

    The effect of the polydimethylsiloxane (PDMS) based silicone oil, that is widely used in vitreoretinal surgery, on internal structures of the polymer intraocular lenses was investigated. The effect of PDMS was studied on the polymethyl methacrylate (PMMA) rigid lenses and poly(2-hydroxyethyl methacrylate) (PHEMA) flexible lenses. The research was carried out by means of the positron lifetime spectroscopy (PALS) as well as the infrared spectroscopy (FT-IR) and the Raman spectroscopy (RS). The studies involving the use of PALS and FT-IR methods have revealed that the PHEMA based lenses absorbed, whereas the PMMA lenses did not absorb, silicone oil. The results obtained with the use of the RS method were inconclusive, probably due to the too low intensity of the characteristic PDMS bands. The evidence from this study was discussed in terms of physics and related to the clinical use of both silicone oil and intraocular lenses.

  9. Scleral fixation of intraocular lenses using Gore-Tex suture: clinical outcomes and safety profile.

    Science.gov (United States)

    Khan, M Ali; Gupta, Omesh P; Smith, Ryan G; Ayres, Brandon D; Raber, Irving M; Bailey, Robert S; Hsu, Jason; Spirn, Marc J

    2016-05-01

    To report the short-term safety profile and clinical outcomes of scleral fixation of intraocular lenses (IOLs) using Gore-Tex suture. Retrospective, interventional case series. 85 eyes of 84 patients undergoing ab externo scleral fixation of a Bausch and Lomb Akreos AO60 or Alcon CZ70BD IOL using Gore-Tex suture. Primary outcome measures were change in visual acuity and occurrence of intraoperative and postoperative complications with minimum follow-up of 90 days. 85 eyes of 84 patients were identified. Mean logarithm of the minimum angle of resolution visual acuity improved from 1.43±0.72 (20/538 Snellen equivalent) preoperatively to 0.64±0.61 (20/87 Snellen equivalent) postoperatively (pGore-Tex suture was well tolerated in all cases. No suture-related complications were encountered. This procedure led to improvement in visual acuity and was not associated with significant intraoperative or postoperative complications. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  10. Hydrophobic modification of polymethyl methacrylate as intraocular lenses material to improve the cytocompatibility.

    Science.gov (United States)

    Wang, Bailiang; Lin, Quankui; Shen, Chenghui; Tang, Junmei; Han, Yuemei; Chen, Hao

    2014-10-01

    The development of posterior capsule opacification (PCO) after intraocular lenses (IOL) implantation for dealing with cataract is mainly due to the severe loss of the human lens epithelial cells (HLECs) during surgery contact. A novel poly (hedral oligomeric silsesquioxane-co-methyl methacrylate) copolymer (allyl POSS-PMMA) was synthesized by free radical polymerization method to promote the adhesion of HLECs. FT-IR and (1)H NMR measurements indicated the existence of POSS cage in the product, which demonstrated the successful synthesis of allyl POSS-PMMA copolymer. Effect of allyl POSS in the hybrids on crystal structure, surface wettability and morphology, optical transmission, thermodynamic properties and cytocompatibility was investigated in detail. X-ray diffraction peaks at 2θ∼11° and 12° indicated that POSS molecules had aggregated and crystallized. Thermogravimetric analysis-differential scanning calorimeter and optical transmission measurements confirmed that the allyl POSS-PMMA copolymer had high glass transition temperatures (more than 100°C) and good transparency. The hydrophilicity and morphology of PMMA and copolymers surfaces were characterized by static water contact angle and atomic force microscopy. The results revealed that the surface of the allyl POSS-PMMA copolymer displayed higher hydrophobicity and higher roughness than that of pure PMMA. The surface biocompatibility was evaluated by morphology and activity measurement with HLECs in vitro. The results verified that the surface of allyl POSS-PMMA copolymer films had more HLECs adhesion and better spreading morphology than that of PMMA film.

  11. Capsule Contraction Syndrome with a Microincision Foldable Hydrophilic Acrylic Intraocular Lens: Two Case Reports and Review of the Literature

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    Angelo Balestrazzi

    2014-10-01

    Full Text Available Here we present 2 cases of capsule contraction syndrome (CCS. In both cases, a hydrophilic acrylic Akreos MI60 (Bausch and Lomb intraocular lens (IOL was implanted in the capsular bag through microincision cataract surgery, and the literature on the subject is reviewed. Since CCS has been described after the implantation of every IOL type, it is unlikely that the Akreos MI60 chemical and physical properties may cause CCS. When CCS occurs with IOLs composed of increasingly flexible materials that are inserted through incisions of decreasing size, a severe dislocation and deformation of IOL optics and haptics may develop. In both cases illustrated here, Nd:YAG laser anterior capsulotomy was highly effective. Hence, also based on the literature, which reports severe complications as a result of surgical intervention, it is suggested that Nd:YAG laser anterior capsulotomy be the first line of CCS treatment when the luxation of an IOL capsular bag is absent.

  12. Capsule contraction syndrome with a microincision foldable hydrophilic acrylic intraocular lens: two case reports and review of the literature.

    Science.gov (United States)

    Balestrazzi, Angelo; Malandrini, Alex; Martone, Gianluca; Marigliani, Davide; Caporossi, Tomaso; Tosi, Gian Marco

    2014-09-01

    Here we present 2 cases of capsule contraction syndrome (CCS). In both cases, a hydrophilic acrylic Akreos MI60 (Bausch and Lomb) intraocular lens (IOL) was implanted in the capsular bag through microincision cataract surgery, and the literature on the subject is reviewed. Since CCS has been described after the implantation of every IOL type, it is unlikely that the Akreos MI60 chemical and physical properties may cause CCS. When CCS occurs with IOLs composed of increasingly flexible materials that are inserted through incisions of decreasing size, a severe dislocation and deformation of IOL optics and haptics may develop. In both cases illustrated here, Nd:YAG laser anterior capsulotomy was highly effective. Hence, also based on the literature, which reports severe complications as a result of surgical intervention, it is suggested that Nd:YAG laser anterior capsulotomy be the first line of CCS treatment when the luxation of an IOL capsular bag is absent.

  13. Glare disability and spherical aberration with five foldable intraocular lenses: a prospective randomized study.

    Science.gov (United States)

    Casprini, Fabrizio; Balestrazzi, Angelo; Tosi, Gian Marco; Miracco, Flavia; Martone, Gianluca; Cevenini, Gabriele; Caporossi, Aldo

    2005-02-01

    To compare differences in subjective glare and spherical aberration between five foldable intraocular lenses (IOLs) made of different materials and to different designs. This prospective study comprised 175 cataract patients who underwent phacoemulsification and were randomized to receive one of five types of foldable IOL (AcrySof MA30BA, Alcon; Sensar AR40, AMO; AcrySof SA30AL, Alcon; Sensar AR40e, AMO, and Tecnis Z9000, Pharmacia & Upjohn). All patients received a questionnaire investigating the incidence of subjective photic phenomena. Two months postoperatively, we collected data regarding subjective glare and evaluated pupil size, visual acuity and wavefront aberration of the cornea and eye. With regard to difficulty in performing ordinary activities under different light conditions and light and dark adaptation, the difference between the groups was not significant (p > 0.05, chi-squared test). With respect to difficulty in driving at night, the MA30BA group had a significant higher incidence of photic phenomena than the SA30AL, AR40e and Z9000 groups (p < 0.05, chi-squared test). Wavefront measurements revealed a significant difference between the Z9000, AR40e and SA30AL groups, which showed the lowest values, and the MA30BA group, which showed the highest value (p < 0.05, anova with Tamhane posthoc test). New generation IOLs such as the Pharmacia Z9000, AMO AR40e and AcrySof SA30AL have a lower incidence of glare and spherical aberrations; however, their impact on future IOL design should be conditioned by further data, especially regarding posterior capsule opacification.

  14. Contrast sensitivity evaluation of aspheric and spherical intraocular lenses 2 years after implantation.

    Science.gov (United States)

    Caporossi, Aldo; Casprini, Fabrizio; Martone, Gianluca; Balestrazzi, Angelo; Tosi, Gian Marco; Ciompi, Leonardo

    2009-07-01

    To compare the quality of vision with aspheric and spherical intraocular lenses (IOLs) in pseudophakic patients after long-term follow-up. Two hundred eyes of 100 patients with bilateral cataracts were randomly assigned to receive spherical (Acrysof SN60AT [Alcon Laboratories Inc] or Sensar AR40e [Advanced Medical Optics Inc]) or aspheric IOLs (Acrysof SN60WF [Alcon] or Tecnis Z9000 [Advanced Medical Optics]). Ophthalmologic examination, including best spectacle-corrected visual acuity (BSCVA), pupil size, ocular dominance, contrast sensitivity under mesopic and photopic conditions, and wavefront analysis, was performed 2 months and 1 and 2 years after surgery. No statistically significant differences among the four groups in terms of age, pupil diameter, postoperative BSCVA, comeal spherical aberration, and posterior capsular opacification were noted. At all followup examinations, contrast sensitivity results showed no significant differences between the two aspheric IOLs at all spatial frequencies. Under photopic conditions, significant differences (P<.05) between spherical and aspheric IOLs were detected for spatial frequencies of 12 and 18 cycles per degree (cpd) at 2 months and 2 years and 12 cpd at 1 year. Under mesopic conditions, significant differences (P<.05) were detected between spherical and aspheric IOLs for all spatial frequencies at 2 months; all spatial frequencies except 18 cpd at 1 year; and spatial frequencies of 3, 12, and 18 cpd at 2 years. In addition, aspheric IOLs had statistical reductions in total spherical aberration at all follow-up examinations (P<.01). This study confirms that implantation of a modified aspheric IOL improves functional visual performance at 2 years postoperative.

  15. Optical performance of toric intraocular lenses in the presence of decentration

    Institute of Scientific and Technical Information of China (English)

    Bin; Zhang; Jin-Xue; Ma; Dan-Yan; Liu; Ying-Hua; Du; Cong-Rong; Guo; Yue-Xian; Cui

    2015-01-01

    · AIM: To evaluate the optical performance of toric intraocular lenses(IOLs) after decentration and with different pupil diameters, but with the IOL astigmatic axis aligned.· METHODS: Optical performances of toric T5 and SN60 AT spherical IOLs after decentration were tested on a theoretical pseudophakic model eye based on the Hwey-Lan Liou schematic eye using the Zemax ray-tracing program. Changes in optical performance were analyzed in model eyes with 3-mm, 4-mm, and 5-mm pupil diameters and decentered from 0.25 mm to 0.75 mm with an interval of 5° at the meridian direction from0° to 90°. The ratio of the modulation transfer function(MTF) between a decentered and a centered IOL(MTFDecentration/MTFCentration) was calculated to analyze the decrease in optical performance.· RESULTS: Optical performance of the toric IOL remained unchanged when IOLs were decentered in any meridian direction. The MTFs of the two IOLs decreased,whereas optical performance remained equivalent after decentration. The MTFDecentration/MTFCentrationratios of the IOLs at a decentration from 0.25 mm to 0.75 mm were comparable in the toric and SN60 AT IOLs. After decentration, MTF decreased further, with the MTF of the toric IOL being slightly lower than that of the SN60 AT IOL. Imaging qualities of the two IOLs decreased when the pupil diameter and the degree of decentration increased, but the decrease was similar in the toric and spherical IOLs.· CONCLUSION: Toric IOLs were comparable to spherical IOLs in terms of tolerance to decentration at the correct axial position.

  16. Change in efficiency of aspheric intraocular lenses based on pupil diameter.

    Science.gov (United States)

    Eom, Youngsub; Yoo, Eunjoo; Kang, Su-Yeon; Kim, Hyo-Myung; Song, Jong-Suk

    2013-03-01

    To measure the effect of spherical aberration correction by aspheric intraocular lenses (IOLs) based on pupil diameter, and to determine the minimum pupil diameter for each aspheric IOL. Retrospective cross-sectional study. Eight-six patients (169 eyes) who were implanted with a HOYA AF-1 NY-60 (HOYA Corporation) or Tecnis ZCB00 1-piece IOL (Abbott Medical Optics Inc) were enrolled. Ocular, corneal, and internal spherical aberrations were measured at the 1-month postoperative visit using the Wavefront Analyzer KR-1W (Topcon). Minimum pupil diameter, which is required for each aspheric IOL to be effective, was calculated using a regression equation. The mean value of internal spherical aberration of the Tecnis ZCB00 group (-0.09 ± 0.094 μm) was lower than that of the HOYA NY-60 group (-0.05 ± 0.072 μm) (P = .005). The original negative spherical aberrations of the HOYA NY-60 (-0.18 μm) were measured at a pupil diameter of 5.6 mm, and for the Tecnis ZCB00 (-0.27 μm) at a pupil diameter of 6.1 mm. The aspheric IOL efficiency dropped to 0% when the pupil diameter was 3.47 mm for the Tecnis ZCB00 group and 3.71 mm for the HOYA NY-60 group. When the pupil diameters of patients are smaller than 3.4 mm for the Tecnis ZCB00 and 3.7 mm for the HOYA NY-60, the spherical aberration correction using these aspheric IOLs seems to be ineffective. Approximately 10% of the eyes showed smaller pupil size than the minimum effective diameter under mesopic conditions. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Personal A-constant in relation to axial length with various intraocular lenses

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    Mohamed A Eldaly

    2014-01-01

    Full Text Available Purpose: To study the relationship between the axial length and personal A-constant for the 1-piece Tecnis (Abbott ZCB00, AcrySof MA60AC (Alcon and the Quatrix aspheric preloaded (CROMA intraocular lenses (IOL. Materials and Methods: Patients matching the inclusion criteria were further subdivided according to the implanted IOL in this prospective comparative study. The obtained refractive outcomes were introduced into the formula installed in the biometry machine (Humphrey model 820 ultrasonic biometer to obtain the personal A-constant for each eye. Polynomial regression analysis was done to study the individualized A-constant for each type of IOL in relation to preoperative axial length measurement. Results: Two hundred and forty five eyes of 186 patients were enrolled into this study, of whom 73 eyes with Tecnis 1-piece, 116 eyes with MA60AC, and 56 eyes with Quatrix. The median of personalized A-constant for Tecnis 1-piece, MA60AC, and Quatrix were 119.21 (SD 1.3, Std. Mean error 0.15, 119 (SD 1.2, Std. Mean error 0.11 and 120.4 (SD 1.2, Std. Mean error 0.16 respectively. Regression plots for the same range of axial length among all the groups showed that the Tecnis1 group followed the same pattern of the Quatrix group in which there was a linear relationship of a trend towards myopia when the axial length had increased and a hyperopic shift when decreased. This relationship changed into a plateau when the axial length became in the range of 23.5 mm to 27 mm in the MA60AC group. Conclusions: Personal A-constant follows different trends with different IOLs even for the same range of axial length.

  18. Modification of hydrophobic acrylic intraocular lens with poly(ethylene glycol) by atmospheric pressure glow discharge: A facile approach

    Energy Technology Data Exchange (ETDEWEB)

    Lin Lin; Wang Yao; Huang Xiaodan [Eye Center, Affiliated Second Hospital, College of Medicine, Zhejiang University, Hangzhou 310009 (China); Xu Zhikang [Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education), Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Yao Ke, E-mail: xlren@zju.edu.cn [Eye Center, Affiliated Second Hospital, College of Medicine, Zhejiang University, Hangzhou 310009 (China)

    2010-10-01

    To improve the anterior surface biocompatibility of hydrophobic acrylic intraocular lens (IOL) in a convenient and continuous way, poly(ethylene glycol)s (PEGs) were immobilized by atmospheric pressure glow discharge (APGD) treatment using argon as the discharge gas. The hydrophilicity and chemical changes on the IOL surface were characterized by static water contact angle and X-ray photoelectron spectroscopy to confirm the covalent binding of PEG. The morphology of the IOL surface was observed under field emission scanning electron microscopy and atomic force microscopy. The surface biocompatibility was evaluated by adhesion experiments with platelets, macrophages, and lens epithelial cells (LECs) in vitro. The results revealed that the anterior surface of the PEG-grafted IOL displayed significantly and permanently improved hydrophilicity. Cell repellency was observed, especially in the PEG-modified IOL group, which resisted the attachment of platelets, macrophages and LECs. Moreover, the spread and growth of cells were suppressed, which may be attributed to the steric stabilization force and chain mobility effect of the modified PEG. All of these results indicated that hydrophobic acrylic IOLs can be hydrophilic modified by PEG through APGD treatment in a convenient and continuous manner which will provide advantages for further industrial applications.

  19. Comparison of outcomes with multifocal intraocular lenses: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Béatrice Cochener

    2011-01-01

    Full Text Available Béatrice Cochener1, Antoine Lafuma2, Babak Khoshnood2, Laurène Courouve2, Gilles Berdeaux3,41Centre Hospitalier Universitaire Brest, Brest, France; 2Cemka Eval, Bourg la Reine, France; 3Alcon France, Rueil-Malmaison, France; 4Conservatoire National des Arts et Métiers, Paris, FrancePurpose: To compare the clinical outcome of different multifocal intraocular lenses (IOLs based on information reported in the international literature.Methods: All comparative clinical trials that involved implanting at least one multifocal IOL in patients with cataract or presbyopia were extracted from the literature. Clinical outcomes included uncorrected near visual acuity, uncorrected distance visual acuity, visual acuity, spectacle independence, and halos. Random effects meta-analyses were conducted to compare outcomes for the different IOL types.Results: Twenty papers were identified describing 11 monofocal IOLs and 35 multifocal IOLs (19 diffractive, including 12 ReSTOR®, 14 refractive, and two accommodative patient cohorts. Multifocal and monofocal uncorrected distance visual acuity was 0.165 (0.090–0.240 and 0.093 (0.088–0.098, respectively. Compared with monofocal IOLs, multifocal IOLs produced better uncorrected near visual acuity (0.470 [0.322–0.618] versus 0.141 [0.131–0.152]; P < 0.0001, resulting in higher spectacle independence (incidence rate ratio [IRR] 3.62 [2.90–4.52]; P < 0.0001. Compared with refractive multifocal IOLs, diffractive multifocal IOLs produced a similar uncorrected distance visual acuity (0.105 [0.098–0.111] versus 0.085 [0.029–0.140]; P ≤ 0.78, not significant and better uncorrected near visual acuity (0.217 [0.118–0.317] versus 0.082 [0.067–0.098]; P < 0.0001 resulting in higher spectacle independence (IRR 1.75 [1.24–2.48]; P < 0.001. Compared with other multifocal IOLs, ReSTOR produced a better uncorrected distance visual acuity (0.067 [0.059–0.076] versus 0.093 [0.088–0.098]; P < 0.0001 and better

  20. Comparison of results obtained with keratophakia, hypermetropic keratomileusis, intraocular lens implantation, and extended-wear contact lenses.

    Science.gov (United States)

    Swinger, C A

    1983-01-01

    The limited experience with LRK precludes a valid comparison with IOLs and extended-wear contact lenses. Only observations, unsupported by valid statistical analysis, are possible. Some of these observations follow. Technically, LRK is very difficult. In their present form, the classic Barraquer procedures could never be used widely. However, if lenticle banks were to supply preground lenticles, the level of difficulty of LRK procedures would be comparable to IOL implantation. The magnitude of refractive correction possible with LRK compares favorably with that of contact lenses and IOLs. However, the accuracy of achieving a given correction is lower with LRK. Unlike contact lenses or IOLs, LRK induces both regular and irregular astigmatism. The latter accounts, in part, for the delayed visual result with LRK. The percentage of patients with 20/40 or better vision following LRK compares favorably with the percentages for contact lenses or IOLs, whereas the percentage of patients with 20/25 or better vision does not. This is true for at least 1 year following surgery. Compared to extended-wear contact lenses, IOLs and LRK typically require less commitment, fewer postoperative visits, and less expenditure by the patient, in terms of time and money, to achieve full-time correction. Although LRK is associated with a number of postoperative complications, none are known to be intraocular, and there have been no known reports of permanent severe visual loss. In contrast, the patient with an extended-wear contact lens or IOL is permanently at risk to develop sight-threatening complications. This is not the case with LRK, which has no known complications after the early postoperative period. Application of the IOL or extended-wear contact lens to the neonate or pediatric patient is associated with increased risk and difficulty. This may not be true with LRK, especially epikeratophakia. The major advantages of LRK appear to be permanent optical correction without the threat

  1. Aderência bacteriana in vitro a lentes intra-oculares de polimetilmetacrilato e de silicone In vitro bacterial adherence to silicone and polymetylmethacrylate intraocular lenses

    Directory of Open Access Journals (Sweden)

    Claudete Inês Locatelli

    2004-04-01

    Full Text Available OBJETIVOS: Verificar a aderência bacteriana a lentes intra-oculares de silicone e de polimetilmetacrilato como possível fator de risco no desenvolvimento de endoftalmite pós-operatória, utilizando-se um modelo in vitro com três microrganismos potencialmente patogênicos. MÉTODOS: As análises foram realizadas com cepas de Staphylococcus aureus ATCC 29213, Staphylococcus epidermidis (amostra clínica e Pseudomonas aeruginosa ATCC 27853 incluindo a determinação de curvas de crescimento, testes para verificação de produção de cápsula, avaliação da hidrofobicidade, testes de aderência a diferentes materiais, microscopia óptica, microscopia eletrônica de varredura e microscopia de força atômica. RESULTADOS: A produção de cápsula e a aderência das três diferentes cepas não mostraram qualquer relação com a quantidade de microrganismos; em relação às lentes intra-oculares de polimetilmetacrilato e de silicone, não houve diferença estatisticamente significativa na aderência de S. aureus e S. epidermidis; P. aeruginosa foi o microrganismo mais aderente a ambos os materiais. A microscopia eletrônica de varredura confirmou estes achados em relação à aderência, ao peso que a microscopia de força atômica evidenciou a produção de biofilme pelas cepas de S. aureus, S. epidermidis e P. aeruginosa. CONCLUSÕES: Constatou-se, in vitro, que os materiais analisados não diferiram com relação à taxa de aderência bacteriana, porém, P. aeruginosa apresentou maior eficiência de adesão entre as bactérias testadas. Todas as cepas produziram biofilme. Silicone foi o material mais hidrofóbico, quando comparado ao polimetilmetacrilato.PURPOSE: To evaluate bacterial adherence to silicone and polymetylmethacrylate (PMMA intraocular lenses as a risk factor for postsurgery endophthalmitis by using an in vitro model with three potentially pathogenic microorganisms. METHODS: In vitro experiments were carried out with the

  2. Safety and effectiveness of a glistening-free single-piece hydrophobic acrylic intraocular lens (enVista

    Directory of Open Access Journals (Sweden)

    Packer M

    2013-09-01

    Full Text Available Mark Packer,1 Luther Fry,2 Kevin T Lavery,3 Robert Lehmann,4 James McDonald,5 Louis Nichamin,6 Brian Bearie,7,† Jon Hayashida,8 Griffith E Altmann,8 Omid Khodai8 1Department of Ophthalmology, Oregon Health and Science University, Eugene, OR, USA; 2University of Kansas Medical Center, Kansas City, KS, USA; 3Wayne State University, Detroit, MI, USA; 4Baylor College of Medicine, Houston, TX, USA; 5University of Arkansas for Medical Sciences, Little Rock, AR, USA; 6Laurel Eye Clinic, Brookville, PA, USA; 7Grand Rapids Eye Institute, Grand Rapids, MI, USA; 8Bausch & Lomb, Aliso Viejo, CA, USA †Brian Bearie passed away on March 9, 2011 Purpose: To evaluate the safety and effectiveness of a single-piece hydrophobic acrylic intraocular lens (IOL; enVista model MX60; Bausch & Lomb, Rochester, NY, USA when used to correct aphakia following cataract extraction in adults. Methods: This was a prospective case series (NCT01230060 conducted in private practices in the US. Eligible subjects were adult patients with age-related cataract amenable to treatment with standard phacoemulsification/extracapsular cataract extraction. With follow-up of 6 months, primary safety and effectiveness end points included the rates of US Food and Drug Administration (FDA-defined cumulative and persistent adverse events and the percentage of subjects who achieved best-corrected visual acuity (BCVA of 20/40 or better at final visit. To evaluate rotational stability, subjects were randomized (1:1:1:1 to have the lens implanted in one of four axis positions in 45° increments. Results: A total of 122 subjects were enrolled. The rate of cumulative and persistent adverse events did not significantly exceed historical controls, as per FDA draft guidance. At the final postoperative visit, all subjects (100% achieved a BCVA of 20/40 compared with the FDA historical control of 96.7%. Rotation of the IOL between the two final follow-up visits was ≤5° for 100% of eyes, and refractive

  3. Evaluation of a new single-piece 4% water content hydrophobic acrylic intraocular lens in the rabbit model.

    Science.gov (United States)

    Ollerton, Andrew; Werner, Liliana; Fuller, Stanley R; Kavoussi, Shaheen C; McIntyre, J Steele; Mamalis, Nick

    2012-10-01

    To evaluate uveal and capsular biocompatibility of a 1-piece intraocular lens (IOL) manufactured from a new hydrophobic acrylic material that incorporates a barrier step at the optic-haptic junctions. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. The study IOL (Eternity-Uni W-60) was implanted in the right eyes of 5 New Zealand rabbits and the control IOL (Acrysof SN60WF) in the left eyes. Slitlamp examination was performed 1 through 4 weeks postoperatively. After death, the globes were enucleated and fixed in formalin. Capsular bag opacification scoring (Miyake-Apple view) was then performed followed by complete histopathology. At the 4-week examination, the mean posterior capsule opacification (PCO) score was 1.5 ± 1.0 (SD) in the study group and 2.2 ± 1.09 in the control group (P=.02). Anterior capsule opacification (ACO) was not present in the study eyes and was mild in the control eyes. On gross examination, the mean central PCO score was 0.9 ± 0.65 in the study group and 1.7 ± 1.20 in the control group (P=.07); the mean peripheral PCO score was 1.3 ± 0.67 and 2.4 ± 1.14 (P=.01) and the mean Soemmerring ring score was 3.8 ± 0.44 and 4.2 ± 1.09, respectively (P=.47). Histopathology confirmed that both IOLs were equally tolerated by the rabbit eyes. In this rabbit study, the new hydrophobic acrylic material was biocompatible. The barrier step incorporated to the optic-haptic junctions has the potential to enhance PCO prevention. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  4. Controlled release of moxifloxacin from intraocular lenses modified by Ar plasma-assisted grafting with AMPS or SBMA: An in vitro study.

    Science.gov (United States)

    Pimenta, A F R; Vieira, A P; Colaço, R; Saramago, B; Gil, M H; Coimbra, P; Alves, P; Bozukova, D; Correia, T R; Correia, I J; Guiomar, A J; Serro, A P

    2017-08-01

    Intraocular lenses (IOLs) present an alternative for extended, local drug delivery in the prevention of post-operative acute endophthalmitis. In the present work, we modified the surface of a hydrophilic acrylic material, used for manufacturing of IOLs, through plasma-assisted grafting copolymerization of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) or [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA), with the aim of achieving a controlled and effective drug release. The material was loaded with moxifloxacin (MFX), a commonly used antibiotic for endophthalmitis prevention. The characterization of the modified material showed that relevant properties, like swelling capacity, wettability, refractive index and transmittance, were not affected by the surface modification. Concerning the drug release profiles, the most promising result was obtained when AMPS grafting was done in the presence of MFX. This modification led to a higher amount of drug being released for a longer period of time, which is a requirement for the prevention of endophthalmitis. The material was found to be non-cytotoxic for rabbit corneal endothelial cells. In a second step, prototype IOLs were modified with AMPS and loaded with MFX as previously and, after sterilization and storage (30days), they were tested under dynamic conditions, in a microfluidic cell with volume and renovation rate similar to the eye aqueous humour. MFX solutions collected in this assay were tested against Staphylococcus aureus and Staphylococcus epidermidis and the released antibiotic proved to be effective against both bacteria until the 12th day of release. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Dynamic performance of accommodating intraocular lenses in a negative feedback control system: a simulation-based study.

    Science.gov (United States)

    Schor, Clifton M; Bharadwaj, Shrikant R; Burns, Christopher D

    2007-07-01

    A dynamic model of ocular accommodation is used to simulate the stability and dynamic performance of accommodating intraocular lenses (A-IOLs) that replace the hardened natural ocular lens that is unable to change focus. Accommodation simulations of an older eye with A-IOL materials having biomechanical properties of a younger eye illustrate overshoots and oscillations resulting from decreased visco-elasticity of the A-IOL. Stable dynamics of an A-IOL are restored by adaptation of phasic and tonic neural-control properties of accommodation. Simulations indicate that neural control must be recalibrated to avoid unstable dynamic accommodation with A-IOLs. An interactive web-model of A-IOL illustrating these properties is available at http://schorlab.berkeley.edu.

  6. A novel full-angle scanning light scattering profiler to quantitatively evaluate forward and backward light scattering from intraocular lenses

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Bennett N., E-mail: bennett.walker@fda.hhs.gov [Optical Therapeutics and Medical Nanophotonics Laboratory, Office of Science and Engineering Laboratories, U.S. Food and Drug Administration, Silver Spring, Maryland 20993 (United States); Office of Device Evaluation, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland 20993 (United States); James, Robert H.; Ilev, Ilko K. [Optical Therapeutics and Medical Nanophotonics Laboratory, Office of Science and Engineering Laboratories, U.S. Food and Drug Administration, Silver Spring, Maryland 20993 (United States); Calogero, Don [Office of Device Evaluation, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland 20993 (United States)

    2015-09-15

    Glare, glistenings, optical defects, dysphotopsia, and poor image quality are a few of the known deficiencies of intraocular lenses (IOLs). All of these optical phenomena are related to light scatter. However, the specific direction that light scatters makes a critical difference between debilitating glare and a slightly noticeable decrease in image quality. Consequently, quantifying the magnitude and direction of scattered light is essential to appropriately evaluate the safety and efficacy of IOLs. In this study, we introduce a full-angle scanning light scattering profiler (SLSP) as a novel approach capable of quantitatively evaluating the light scattering from IOLs with a nearly 360° view. The SLSP method can simulate in situ conditions by controlling the parameters of the light source including angle of incidence. This testing strategy will provide a more effective nonclinical approach for the evaluation of IOL light scatter.

  7. Comparison between bilateral implantation of a trifocal intraocular lens and blended implantation of two bifocal intraocular lenses

    Directory of Open Access Journals (Sweden)

    Vilar C

    2017-08-01

    Full Text Available César Vilar,1,2 Wilson Takashi Hida,1–3 André Lins de Medeiros,1,2 Klayny Rafaella Pereira Magalhães,2 Patrick Frensel de Moraes Tzelikis,1,2 Mario Augusto Pereira Dias Chaves,2,4 Antônio Francisco Pimenta Motta,2,3 Pedro Carlos Carricondo,1–3 Milton Ruiz Alves,3 Walton Nosé5 1Cataract Division, Brasília Ophthalmologic Hospital (HOB, Brasília-DF, Brazil; 2Renato Ambrosio Ophthalmologic Research Center (CEORA, 3Ophthalmology Department, São Paulo University – USP, São Paulo-SP, Brazil; 4Cataract Division, ProVisão, João Pessoa-PB, Brazil; 5Ophthalmology Department, Paulista Medical School – UNIFESP, São Paulo-SP, Brazil Purpose: To compare visual outcomes and performance between bilateral implantation of a diffractive trifocal intraocular lens (IOL Acrysof®PanOptix® TFNT00 and blended implantation of two different near add power bifocal IOLs: Acrysof® Restor® SV25T0 in dominant eye and Acrysof® Restor® SN6AD1 in the nondominant eye.Methods: This prospective, nonrandomized, consecutive and comparative study assessed 20 patients (40 eyes who had bilateral cataract surgery performed using the IOLs described. Patients were divided into groups, bilateral trifocal implant and blended implant. Evaluation included measurement of binocular uncorrected and corrected distance visual acuity at 4 m (UDVA, CDVA and uncorrected intermediate (60 cm and near (at 40 cm visual acuity; contrast sensitivity (CS and visual defocus curve.Results: Postoperative CDVA comparison showed no statistical significance between groups. UDVA was significantly better in the trifocal groups. Under photopic conditions, the trifocal group had better CS in higher frequencies with and without glare. The binocular defocus curve demonstrated a trifocal behavior in both groups, with the bilateral trifocal group exhibiting better performance for intermediate vision.Conclusion: Both lens combinations were able to provide good near, intermediate and distance vision

  8. Comparison of ocular straylight after implantation of multifocal intraocular lenses

    NARCIS (Netherlands)

    Łabuz, Grzegorz; Reus, Nicolaas J; van den Berg, Thomas J T P

    2016-01-01

    UNLABELLED: A comprehensive review of the effect of multifocal intraocular lens (IOL) designs on postoperative ocular straylight was performed. Studies reporting straylight values obtained with the natural pupil using the C-Quant device after uneventful multifocal IOL implantation were included. The

  9. AN EXPERIMENTAL STUDY OF THE INTERLEUKIN 1 LEVELS IN AQUEOUS HUMOR AFTER TRANSSCLERAL FIXATION OF INTRAOCULAR LENSES

    Institute of Scientific and Technical Information of China (English)

    周朝晖; 何守志

    1998-01-01

    Purpose. To study the interleukin 1 (IL-1) levels in aqueous humor after transscleroal fixation of intraocular lenses (IOLs) implantation in rabbits and disciss the effect of IL-1 on postoperative anterior ocular inflammation, Methods. Twenty-seven pigmented rabbits were divided into three groups: G1, transscleral fixation of posterior chamber (PC) IOLs implantation; G2, Lens of rabbits were removed without IOLs implantation; GS, the control group, without surgical intervention. On the Ist, 3rd, 7th and 14th postoperative days, aqueous humor samples were obtained. Methyl thiazolyl tetrazolium(MTT) colormetry was used to detected for the presence of IL-1. The data were analyzed hy using analysis of variance of SAS soft ware. Results. It was found that IL-1 level in aqueous humor was increased after transscleral fixation of IOLs implantatlon, IL-1 level reached its maximum on the 14th postoperative days in the IOL implanted group. IL-1 levels on 1st, 3rd, 7th and 14th days postoperatively was significantly higher (P<0. 05) in IOLs implanted group than that of only extracapsular lenses extraction but no IOLs implantation group and that of the none sttrgical intervention group. Conclusions. IL-1 levels increased had a close relationship with a specific response to IOL implantation. The increase of IL-1 may be suggested as the principal mediators of immunological and inflammlatory responses, so that may play critical role in anterior ocular inflammative response after IOL implantation.

  10. Optical aberrations of intraocular lenses measured in vivo and in vitro

    Science.gov (United States)

    Barbero, Sergio; Marcos, Susana; Jiménez-Alfaro, Ignacio

    2003-10-01

    Corneal and ocular aberrations were measured in a group of eyes before and after cataract surgery with spherical intraocular lens (IOL) implantation by use of well-tested techniques developed in our laboratory. By subtraction of corneal from total aberration maps, we also estimated the optical quality of the intraocular lens in vivo. We found that aberrations in pseudophakic eyes are not significantly different from aberrations in eyes before cataract surgery or from previously reported aberrations in healthy eyes of the same age. However, aberrations in pseudophakic eyes are significantly higher than in young eyes. We found a slight increase of corneal aberrations after surgery. The aberrations of the IOL and the lack of balance of the corneal spherical aberrations by the spherical aberrations of the intraocular lens also degraded the optical quality in pseudophakic eyes. We also measured the aberrations of the IOL in vitro, using an eye cell model, and simulated the aberrations of the IOL on the basis of the IOL's physical parameters. We found a good agreement among in vivo, in vitro, and simulated measures of spherical aberration: Unlike the spherical aberration of the young crystalline lens, which tends to be negative, the spherical aberration of the IOL is positive and increases with lens power. Computer simulations and in vitro measurements show that tilts and decentrations might be contributors to the increased third-order aberrations in vivo in comparison with in vitro measurements.

  11. Bilateral implantation of +2.5 D multifocal intraocular lens and contralateral implantation of +2.5 D and +3.0 D multifocal intraocular lenses: Clinical outcomes.

    Science.gov (United States)

    Nuijts, Rudy M M A; Jonker, Soraya M R; Kaufer, Robert A; Lapid-Gortzak, Ruth; Mendicute, Javier; Martinez, Cristina Peris; Schmickler, Stefanie; Kohnen, Thomas

    2016-02-01

    To assess the clinical visual outcomes of bilateral implantation of Restor +2.5 diopter (D) multifocal intraocular lenses (IOLs) and contralateral implantation of a Restor +2.5 D multifocal IOL in the dominant eye and Restor +3.0 D multifocal IOL in the fellow eye. Multicenter study at 8 investigative sites. Prospective randomized parallel-group patient-masked 2-arm study. This study comprised adults requiring bilateral cataract extraction followed by multifocal IOL implantation. The primary endpoint was corrected intermediate visual acuity (CIVA) at 60 cm, and the secondary endpoint was corrected near visual acuity (CNVA) at 40 cm. Both endpoints were measured 3 months after implantation with a noninferiority margin of Δ = 0.1 logMAR. In total, 103 patients completed the study (53 bilateral, 50 contralateral). At 3 months, the mean CIVA at 60 cm was 0.13 logMAR and 0.10 logMAR in the bilateral group and contralateral group, respectively (difference 0.04 logMAR), achieving noninferiority. Noninferiority was not attained for CNVA at 40 cm; mean values at 3 months for bilateral and contralateral implantation were 0.26 logMAR and 0.11 logMAR, respectively (difference 0.15 logMAR). Binocular defocus curves suggested similar performance in distance vision between the 2 groups. Treatment-emergent ocular adverse events rates were similar between the groups. Bilateral implantation of the +2.5 D multifocal IOL resulted in similar distance as contralateral implantation of the +2.5 D multifocal IOL and +3.0 D multifocal IOL for intermediate vision (60 cm), while noninferiority was not achieved for near distances (40 cm). Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  12. Late dislocation of in-the-bag intraocular lenses in uveitic eyes: An analysis of management and complications

    Directory of Open Access Journals (Sweden)

    Sudha K Ganesh

    2017-01-01

    Full Text Available Aim: An analysis of late in-the-bag dislocation of intraocular lenses (IOL, in uveitic eyes. Setting: Referral uveitis clinic. Design: Retrospective case series. Materials and Methods: All case records of eyes with chronic uveitis that had phacoemulsification with IOL implantation, at a referral uveitis clinic between February 1997 and January 2015 were retrieved and analyzed. Only those eyes with no documented intraoperative complication and no predisposing risks to IOL dislocation, such as pseudoexfoliation, high myopia, trauma, and prior VR surgery were included in this study. Results: A total of 581 eyes with chronic uveitis underwent phacoemulsification with IOL implantation under steroid cover from February 1997 to December 2015. Out of these 581 eyes, 10 patients (11 eyes had experienced late in-the-bag IOL dislocation (1.89%. All 11 eyes had chronic intermediate uveitis. The mean duration from the time of cataract surgery to IOL dislocation was 11.24 years. 5 out of 11 eyes had pars plana vitrectomy (PPV with IOL removal with 4-point sutured scleral fixated IOL. Two out of 11 eyes had PPV with in-the-bag IOL re-fixation. Out of 11, 2 eyes had PPV with IOL removal only. Remaining 2 eyes of 2 patients did not opt for surgery. Out of 11, 8 eyes had improved vision at last follow-up. Conclusions: In-the-bag dislocation of IOL is a rare late complication in uveitic eyes. With tight perioperative inflammatory control, scleral-fixated posterior chamber intraocular lens or IOL re-fixation are good options of restoring vision in these high-risk eyes.

  13. Aniseikonia for near vision with unilateral aphakia corrected by intraocular lenses.

    Science.gov (United States)

    Ivashina, A I

    1981-11-01

    1. Our methods for calculation of aniseikonia for near vision allow one to determine it in every patient with an intraocular lens. 2. With an eye with an artificial lens there is a correlation between the amount of accommodation used by the phakic eye and aniseikonia changes subject to the distance from the object. Calculations for aniseikonia for near vision in 43 patients showed that with accommodation used by the normal eye aniseikonia was increased by 3.0% to 7.8% as compared with aniseikonia for distance. With accommodation of the phakic eye lacking, aniseikonia for near vision did not differ much from its value for distance. 3. Calculations for aniseikonia for near vision showed the advantage of intraocular lens implantation for obtaining iso-iconia for distance or tolerable aniseikonia not more than 2.5% to 3.0%. 4. For obtaining iso-iconia for near vision it is necessary to correct the phakic eye to switch off its accommodation partially or completely (with emmetropia, correction +2.0D for near vision).

  14. Wavefront aberration and contrast sensitivity after implantation of foldable and rigid iris claw phakic intraocular lenses: Artiflex versus artisan

    Directory of Open Access Journals (Sweden)

    Faroogh Parsipour

    2016-01-01

    Full Text Available Aim of study: The aim of this study is to assess wavefront aberration and contrast sensitivity (CS after implantation of foldable iris claw - artiflex- and rigid iris claw - artisan- phakic intraocular lenses (pIOLs. Materials and Methods: A nonrandomized prospective comparative case study was performed on 57 eyes; of which, 54 were myopia and 3 were hyperopia. Twenty-four patients had artisan pIOL implantation and 33 had artiflex pIOL implantation. Higher-order aberration (HOA and CS were obtained 1 year after surgery. Results: Total HOA in artisan group was greater than artiflex group (P = 0.044 with a mean HOA of 0.44 ± 0.15 root mean square (RMS for artisan and 0.35 ± 0.15 RMS for artiflex. Although, there were no significant differences in the vertical trefoil, vertical coma, horizontal trefoil, horizontal coma, secondary astigmatism, quatrefoil, and fourth order spherical aberration in two groups. CS in mesopic conditions was better in artiflex-treated eyes at three spatial frequencies of 6, 12, and 18 cycles per degree (cpd (P = 0.003, P = 0.007, and P = 0.00, respectively, and no significant difference was seen between two lenses at 3 cpd. Conclusion: Although the components of HOA were not significantly different between two groups, total HOA was higher in artisan group, which may be due to the slight differences in each component, increasing the HOA as a total. CS was significantly better in artiflex group.

  15. Intraocular lens employed for cataract surgery

    Science.gov (United States)

    Roszkowska, A. M.; Torrisi, L.

    2014-04-01

    The aim of this paper is to illustrate the techniques of cataract surgery with implantation of intraocular lenses and some physical properties of the used materials. The new technology, coupled with extensive experience and the studied cases, permits to increase the standardization and accuracy of the engravings, by reducing the use and handling of surgical instruments inside the eye. At present it is possible to replace the cataract with crystalline lenses based on biopolymers such as PMMA, silicone, acrylic hydrophilic and hydrophobic acrylic. These materials are increasingly able to replace the natural lens and to ensure the fully functional of the eye. The role of femtosecond lasers in cataract surgery, to assist or replace several aspects of the manual cataract surgery, are discussed.

  16. Biological safety of hydrophobic acrylic foldable intraocular lens%疏水性丙烯酸酯折叠式人工晶体的生物安全性

    Institute of Scientific and Technical Information of China (English)

    段晓杰; 姜宝光; 王召旭

    2015-01-01

    背景:在临床试验前,需对疏水性丙烯酸酯人工晶体以新西兰白兔作为植入对象进行生物学评价。目的:观察新型疏水性丙烯酸酯折叠式人工晶体的生物安全性。方法:取新西兰家兔12只,右侧眼做实验眼,植入沈阳百奥医疗器械有限公司研制疏水性丙烯酸酯折叠式人工晶体,左侧眼做对照眼,植入美国爱尔康公司的Acrysof IQ SN60WF人工晶体。结果与结论:与对照眼相比,兔实验眼植入后各时间点角膜、前房、植入物位置、眼后节变化差异无显著性意义;且角膜和晶体囊袋无炎症反应,组织增生差异无显著性意义;人工晶体表面无巨噬细胞等炎症细胞,晶体表面、襻根部可见纤维组织。说明此款新材料与临床中已经广泛应用的产品无显著差别,即具有生物安全性。%BACKGROUND:Hydrophobic acrylic foldable intraocular lens should be evaluated biologicaly with New Zealand rabbits as implant objects prior to clinical trial. OBJECTIVE:To observe the biological safety of hydrophobic acrylic foldable intraocular lens. METHODS: Twelve New Zealand rabbits were enroled. The right eyes were implanted with self-developed hydrophobic acrylic foldable intraocular lens (Shenyang Baiao Medical Device Co., Ltd., China) as experimental group, and the left eyes were implanted with Acrysof IQ SN60WF (Alcon, USA) as control group. RESULTS AND CONCLUSION: After implantation, there were no significant differences in the cornea, anterior chamber, implant position, posterior segment of eyebal between two groups. Tissue proliferation had no obviously difference between the two groups, and there were cornea and lens pouch inflammations. No macrophages and other inflammatory cels were visualized on the surface of intraocular lens, and fibrous tissues were found on the intraocular lens surface and in the haptics root. These findings suggest that the self-developed hydrophobic acrylic

  17. A truly knotless technique for scleral fixation of intraocular lenses: Two-year results

    Directory of Open Access Journals (Sweden)

    Naresh K Yadav

    2012-01-01

    Full Text Available Scleral fixated intraocular lens (SFIOL is a safe and effective option for managing optical aphakia. Suture related complications like suture erosion, suture breakage, endophthalmitis, etc. are unique to SFIOL. The knots can be covered by partial thickness flaps or they can be rotated into scleral tissues without flaps to reduce the complications. We performed a recently described novel technique which obviates the need for knot and scleral flaps in securing the SFIOL. This novel 2-point Ab externo knotless technique may reduce the knot related problems. Twenty-three eyes undergoing this knotless SFIOL procedure were analyzed for intraoperative and postoperative complications. Twenty-two eyes either maintained or improved on their preoperative vision. All patients had a minimum follow-up of 24 months.

  18. Implantation of multifocal intraocular lenses using a magnification strategy in cataractous eyes with age-related macular degeneration.

    Science.gov (United States)

    Gayton, Johnny L; Mackool, Richard J; Ernest, Paul H; Seabolt, ReBecca A; Dumont, Susan

    2012-03-01

    To examine visual function after targeting -2.0 diopter (D) spherical equivalent (SE) when implanting a multifocal intraocular lens (IOL) in eyes with cataract and age-related macular degeneration (AMD). Three private practices. Case series. Lenses of cataractous eyes with AMD were replaced with the Acrysof Restor SN60D3 multifocal IOL, targeting an SE of -2.0 D, which yielded +5.2 D near addition. Near and distance visual acuities were examined. Patients completed a visual function questionnaire preoperatively and 6 months postoperatively. At 6 months, 13 patients with 20 eligible eyes were examined. The uncorrected near visual acuity improved in 18 eyes (90%) and was unchanged in 2 eyes. The corrected distance visual acuity improved in 14 eyes (70%), was unchanged in 4 eyes (20%), and decreased (≤ 3 lines) in 2 eyes (10%). All vision-related questionnaire items improved. For cataractous eyes with AMD, replacing the crystalline lens with this myopia-targeted multifocal IOL improved or maintained near vision without severely compromising distance vision. Drs. Mackool and Ernest are consultants to Alcon. Dr. Mackool is an inventor in the patent of the IOLs related to this strategy. No other author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  19. Measuring ultraviolet-visible light transmission of intraocular lenses: double-beam mode versus integrating-sphere mode.

    Science.gov (United States)

    Akinay, Ali; Ong, Marcia D; Choi, Myoung; Karakelle, Mutlu

    2012-10-01

    This study compared integrating-sphere and double-beam methodologies for measuring the ultraviolet/visible transmission of intraocular lenses (IOLs). Transmission spectra of control IOLs and clinically explanted IOLs were measured with an optical spectrophotometer in two optical configurations: single-beam mode with integrating sphere detector and double-beam mode with photodiode detector. Effects of temperature and surface light scattering on transmittance were measured. Effects of lens power were measured and were modeled with ray-tracing software. Results indicated that transmission was consistent over a range of IOL powers when measured with the integrating-sphere configuration, but transmission gradually decreased with increasing IOL power (in a wavelength-dependent fashion) when measured with the double-beam configuration. Ray tracing indicated that the power-dependent loss in transmission was partially due to higher-powered IOLs spreading the light beam outside of the detector area. IOLs with surface light scattering had transmission spectra that differed between double-beam and integrating-sphere configurations in a power-dependent fashion. Temperature (ambient or physiological 35°C) did not affect transmission in the integrating-sphere configuration. Overall, results indicated that double-beam spectrophotometers may be useful for measuring transmittance of low-power IOLs, but an integrating-sphere configuration should be used to obtain accurate measurements of transmittance of higher-power IOLs.

  20. Diagnosis and management of opacified silicone intraocular lenses in patients with asteroid hyalosis.

    Science.gov (United States)

    Espandar, Ladan; Mukherjee, Nisha; Werner, Liliana; Mamalis, Nick; Kim, Terry

    2015-01-01

    We analyzed 3 calcified silicone IOLs from 2 patients with a history of asteroid hyalosis. In both cases, posterior capsule opacification had been diagnosed and a laser capsulotomy performed before referral. Subsequently, both IOLs were exchanged with hydrophobic acrylic IOLs that were placed in the sulcus. The IOL exchange was challenging due to the open capsule. Light microscopy demonstrated that the white deposits on the explanted IOLs formed an almost confluent crust in some areas, interspersed with clear areas on the posterior optic surfaces. The findings in our cases and in other reported cases may affect the choice of IOL in the presence of asteroid hyalosis. Also, ophthalmologists may consider deferring laser posterior capsulotomy treatment in a calcified silicone IOL to facilitate an IOL exchange procedure. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  1. Augmentation of macular pigment following implantation of blue light-filtering intraocular lenses at the time of cataract surgery.

    Science.gov (United States)

    Nolan, John M; O'Reilly, Philip; Loughman, James; Stack, Jim; Loane, Edward; Connolly, Eithne; Beatty, Stephen

    2009-10-01

    (Photo)-oxidative stress is believed to play a role in the pathogenesis of age-related macular degeneration (AMD), with the threshold for retinal damage being lowest for short-wavelength (blue) light. Macular pigment (MP), consisting of the carotenoids lutein (L), zeaxanthin (Z) and meso-Z, has a maximum absorption at 460 nm and protects the retina from (photo)-oxidative injury. This study was designed to investigate whether the blue light-filtering properties of the Alcon AcrySof Natural intraocular lens (ANIOL) implanted during cataract surgery affects MP optical density (MPOD). Forty-two patients scheduled for cataract surgery were recruited for the study. These patients all had a preoperative best corrected visual acuity rating (BCVAR) of at least 0.5 (logMAR) in the study eye. The patients were randomized to have either the standard Alcon AcrySof three-piece acrylic intraocular lens (AIOL) (controls) or the ANIOL implanted at the time of cataract surgery. The spatial profile of MPOD (i.e., at 0.25 degrees, 0.5 degrees, 1.0 degrees, and 1.75 degrees eccentricity) was measured with customized heterochromatic flicker photometry (cHFP) 1 week before and 1 week after surgery, and at 3, 6, and 12 months after surgery. Serum concentrations of L and Z were also measured at each study visit. There was a highly significant and positive correlation between all MPODs (e.g., at 0.25 degrees) recorded 1 week before and after surgery in eyes with an AIOL implant (r = 0.915, P 0.05). There were no significant time or lens effects observed for serum L over the study period (P > 0.05). There was a significant time effect for serum Z over the study period (P 0.05). Customized HFP can reliably measure the MPOD spatial profile in the presence of lens opacity, and cataract surgery does not artifactually alter MPOD readings. This study also provides evidence that implanting an IOL that filters blue light is associated with augmentation of MPOD in the absence of raised serum

  2. A knotless, one-haptic fixation of posterior chamber intraocular lenses: one-year results

    Institute of Scientific and Technical Information of China (English)

    Pipat; Kongsap

    2015-01-01

    AIM: To assess the results of a modified technique for scleral fixation of a posterior chamber intraocular lens(IOL) in eyes which had deficient of posterior capsular support.METHODS: This retrospective study was comprised of ten patients with deficient posterior capsular support who underwent one-haptic fixation of posterior chamber IOLs, between February 2010 and October 2011. IOL as implanted with one haptic supported on the capsular remnant and the other haptic drawn into the sulcus by anchoring suture without a knot. All patients were evaluated for pre- and postoperative visual acuity, lens centration, intra-and postoperative complications.RESULTS: A knotless, one-haptic fixation of posterior chamber IOLs has successfully been performed on ten eyes. All cases had inadequate capsular support(i.e. a capsular tear ranged from 5 to 7 clock hours). The average age was 74.25 ±8.87y(SD). The average postoperative uncorrected visual acuity was 0.51 log MAR.Complications included hyphema in one eye, a mild inflammatory reaction in the anterior chamber in two eyes, and a transient rise in IOP in one eye. Neither IOL tilt nor dislocation was observed and there were no later complications.CONCLUSION: In the presence of insufficient capsular support, a knotless, one-haptic fixation of posterior chamber IOLs is a safe and viable option which reduces the operation time, and minimizes postoperative suture-related complications.

  3. Differences of Longitudinal Chromatic Aberration (LCA) between Eyes with Intraocular Lenses from Different Manufacturers.

    Science.gov (United States)

    Nakajima, Masashi; Hiraoka, Takahiro; Yamamoto, Toshiya; Takagi, Seiu; Hirohara, Yoko; Oshika, Tetsuro; Mihashi, Toshifumi

    2016-01-01

    Several researchers have studied the longitudinal chromatic aberration (LCA) of eyes implanted with an intraocular lens (IOL). We investigated the LCA of eyes implanted with yellow-colored IOLs from three different manufacturers: Alcon Inc., HOYA Corp., and AMO Inc. The number of subjects was 11, 16, and 16, respectively. The LCA of eyes implanted with SN60WF and SN60AT (Alcon Inc.), and with XY-1 (HOYA Corp.), was the same as that of phakic eyes. The LCA of eyes with ZCB00V (AMO Inc.) was smaller than that of phakic eyes. The LCA of eyes implanted with Alcon's and HOYA's IOLs, but not the LCA of eyes implanted with AMO's IOLs, was positively correlated with the powers of the IOLs. We also performed simulations to verify the impacts of LCA on visual performance for 4-mm pupil diameter; the simulations were a polychromatic modulation transfer function (MTF) and a visual Strehl ratio computed on the basis of an optical transfer function (VSOTF). We concluded that the differences between the LCA of different manufacturers do not affect visual performances when some extent of higher-order aberration (HOA) exists. The smaller HOA of AMO IOLs may enhance visual performance.

  4. A knotless, one-haptic fixation of posterior chamber intraocular lenses: one-year results.

    Science.gov (United States)

    Kongsap, Pipat

    2015-01-01

    To assess the results of a modified technique for scleral fixation of a posterior chamber intraocular lens (IOL) in eyes which had deficient of posterior capsular support. This retrospective study was comprised of ten patients with deficient posterior capsular support who underwent one-haptic fixation of posterior chamber IOLs, between February 2010 and October 2011. IOL as implanted with one haptic supported on the capsular remnant and the other haptic drawn into the sulcus by anchoring suture without a knot. All patients were evaluated for pre- and postoperative visual acuity, lens centration, intra-and postoperative complications. A knotless, one-haptic fixation of posterior chamber IOLs has successfully been performed on ten eyes. All cases had inadequate capsular support (i.e. a capsular tear ranged from 5 to 7 clock hours). The average age was 74.25±8.87y (SD). The average postoperative uncorrected visual acuity was 0.51 logMAR. Complications included hyphema in one eye, a mild inflammatory reaction in the anterior chamber in two eyes, and a transient rise in IOP in one eye. Neither IOL tilt nor dislocation was observed and there were no later complications. In the presence of insufficient capsular support, a knotless, one-haptic fixation of posterior chamber IOLs is a safe and viable option which reduces the operation time, and minimizes postoperative suture-related complications.

  5. Scleral Fixation of Posteriorly Dislocated Intraocular Lenses by 23-Gauge Vitrectomy without Anterior Segment Approach

    Directory of Open Access Journals (Sweden)

    Jeroni Nadal

    2015-01-01

    Full Text Available Background. To evaluate visual outcomes, corneal changes, intraocular lens (IOL stability, and complications after repositioning posteriorly dislocated IOLs and sulcus fixation with polyester sutures. Design. Prospective consecutive case series. Setting. Institut Universitari Barraquer. Participants. 25 eyes of 25 patients with posteriorly dislocated IOL. Methods. The patients underwent 23-gauge vitrectomy via the sulcus to rescue dislocated IOLs and fix them to the scleral wall with a previously looped nonabsorbable polyester suture. Main Outcome Measures. Best corrected visual acuity (BCVA LogMAR, corneal astigmatism, endothelial cell count, IOL stability, and postoperative complications. Results. Mean follow-up time was 18.8 ± 10.9 months. Mean surgery time was 33 ± 2 minutes. Mean BCVA improved from 0.30 ± 0.48 before surgery to 0.18 ± 0.60 (p=0.015 at 1 month, which persisted to 12 months (0.18 ± 0.60. Neither corneal astigmatism nor endothelial cell count showed alterations 1 year after surgery. Complications included IOL subluxation in 1 eye (4%, vitreous hemorrhage in 2 eyes (8%, transient hypotony in 2 eyes (8%, and cystic macular edema in 1 eye (4%. No patients presented retinal detachment. Conclusion. This surgical technique proved successful in the management of dislocated IOL. Functional results were good and the complications were easily resolved.

  6. Membrane Formation on the Surface of implanted Posterior Chamber Intraocular Lenses

    Institute of Scientific and Technical Information of China (English)

    FangyaoYang; GuijunWu

    1995-01-01

    Purpose:To study the prevention and treatment of the membrane formation on the lens surface after extracapsular cataract extraction(ECCE)with posterior chamber intraocular lens(PCIOL)implantation.Methods:We reviewed the records of 312 cataractous patients that had undergone ECCEwith PCIOLimplantation between1989and1993,Postoperatively all pa-tients were examined under slit-lamp microscopy.The membrane formation on the surface of PCIOLin pupilar area was divided into four grades.Two mem-branes of surgical removal were observed under a transmission electrom mi-croscopy.One PCIOLof surgical removal was observed under a scanning electron microscopy.Results;Of312 patients,21 had the membrane formation on the surface of the PCIOL postoperatively.The incidence of the membrane formation was6.7%.Comparisone with cases of senile cataract showed the incidence to be significantly the highest among;1.patients who had traumatic cataract(P<0.05);2.pa-tients with complicated cataract(P<0.05).Interoperatively residual lens corten and rupture of posterior capsule,interval time betwwen the first and second eye operations less than 1month are the main factors of menbrane formation.The ultrastructure in membrane and cytology on the lens surface showed that the membrane on the surface of PCIOLs is usually composed of acellular protein film and cellular elements,including macrophages.fibroblast-like cells,epithelioid cells,giant cells,fibroblasts and collagen fibrils,etc.Conclusions:The cellular response on the surface of an implanted PCIOLis a chonic foreign-body inflammatory reaction and the membrane of the surfaceof implanted PCIOL is a reactive membrane of the foreign-body.Eye Science1995;11:131-135.

  7. Materials for intraocular lenses enabling photo-controlled tuning of focal length in vivo

    Science.gov (United States)

    Träger, Jens; Heinzer, Jasmin; Kim, Hee-Cheol; Hampp, Norbert

    2007-07-01

    Typical postoperative complications in cataract surgery are that refractive power and curvature of the implanted intraocular lens (IOL) do not have optimum values, requiring the patient to wear viewing aids. This is mainly because biometric data relevant for calculation of the IOL's shape cannot be determined with the required precision. Hence, there is a need for methods to tune the focal length postoperatively in a non-invasive manner. We have developed polymers where we can induce a change in refractive index by linking or cleaving bonds between a su.ciently large number of side groups of the polymer main chain in a photoinduced cycloaddition or cycloreversion reaction, respectively. These photoreactions lead to a change in refractive index great enough to be interesting for the concept of in vivo tunable IOL's. The photochemical reaction can be triggered by a two-photon process (TPA) using a pulsed laser system, i.e. the energy required for bond breaking is provided by two photons in the visible range. This is important because light in the UV cannot induce undesired changes of the refractive index owing to the strong UV-absorption of the cornea. Undesired changes due to light in the visible range of the spectrum are unlikely to happen because photon density of sun light is much too low for TPA. Due to the excellent spatial resolution that can be achieved with two-photon processes one cannot only modify the refractive index of the entire lens but also selectively in well defined areas enabling to correct for aberrations such as astigmatism. Here, we present new polymers that do not only exhibit a photo induced change of refractive index great enough to induce a change of focal length of more than two diopters in a standard IOL. These new polymers have also significantly improved material properties with respect to the fabrication of the IOL and the TPA-sensitivities and the light energy required to induce the refractive index change.

  8. Tilt and decentration tolerance of intraocular lenses: measurements with an improved mechanical model eye

    Science.gov (United States)

    Traxler, Lukas; Reutterer, Bernd; Bayer, Natascha; Rank, Elisabet; Krause, Sylvio; Beckert, Erik; Drauschke, Andreas

    2016-03-01

    Cataract, a clouding of the crystalline eye lens, is the leading cause of blindness. It can effectively be treated by cataract surgery, where the clouded lens is replaced by an artificial intraocular lens (IOL). Postoperative healing processes can cause a displacement of the IOL, which further leads to the fact that the quality of vision is deteriorated. Studies have shown that the imaging quality of high sophisticated IOL designs is more sensitive to lens displacements than simpler designs. The effects of IOL displacements are not well represented and tested within the current IOL test standard ISO 11979-2. This fact leads to the necessity to develope new test standards for novel and more sophisticated IOL designs. In this paper we present an improved model eye, which extends the current standard in three main aspects: First, the eye-model is very close to the physiology of the human eye. Second, electromechanic drives allow an automatic and precise simulation of postoperative lens tilts and decentrations, and finally in addition to standard conform MTF analysis, in the proposed setup also wavefront aberrations are measured. The latter reveals specific image aberrations caused by lens displacements. The model eye allows to objectively analyze the displacement tolerance of various IOL designs. The functionality of this novel setup is tested by measuring a spherical and an aspheric IOL design. Additionally, for comparison, IOLs that were already investigated with a previous version of the presented model eye are used for analysis. Measurements results reveal improvements compared to the previous version of the model eye and a functional prototype for wavefront measurement.

  9. Prospective randomized study of clinical performance of 3 aspheric and 2 spherical intraocular lenses in 250 eyes.

    Science.gov (United States)

    Caporossi, Aldo; Martone, Gianluca; Casprini, Fabrizio; Rapisarda, Lorenzo

    2007-09-01

    To compare the quality of vision with aspheric and spherical intraocular lenses (IOLs) in pseudophakic patients. This prospective, comparative, randomized study included 250 eyes of 125 patients with bilateral cataracts. Patients were randomly assigned to receive either IOLs with a spherical biconvex optic (Acrysof SN6OAT [Alcon] or Sensar AR40e [Advanced Medical Optics, AMO]) or IOLs with an aspheric optic (Acrysof IQ SN6OWF [Alcon], Tecnis Z9000 [AMO], or Sofport L161AO [Bausch & Lomb]). Ophthalmologic examination including best spectacle-corrected visual acuity, pupil size, ocular dominance investigation, contrast sensitivity under mesopic and photopic conditions, and wavefront analysis was performed 2 months postoperatively. Aspheric IOLs showed better contrast sensitivity compared to spherical IOLs at spatial frequencies of 6, 12, and 18 cycles per degree (cpd) under photopic conditions and at all spatial frequencies under mesopic conditions. There was no significant difference among the three aspheric IOLs at all spatial frequencies under either photopic or mesopic conditions. Mean total spherical aberration was statistically lower in dominant eyes with aspheric IOLs (0.05 +/- 0.06, 0.11 +/- 0.1, and 0.19 +/- 0.08 pm for the Tecnis Z9000, Acrysof IQ SN6OWF, and Sofport L161AO, respectively) compared with eyes with spherical IOLs (0.62 +/- 0.24 and 0.46 +/- 0.19 microm for the Acrysof SN6OAT and Sensar AR40e, respectively) for a 5-mm pupil diameter. The aspheric IOLs had less wavefront aberrations and performed better under both photopic and mesopic contrast sensitivity compared to the spherical IOLs. These findings confirm it is possible to improve the optical performance of IOLs by modifying the surfaces.

  10. Evaluation of actual retinal images produced by misaligned aspheric intraocular lenses in a model eye

    Directory of Open Access Journals (Sweden)

    Fujikado T

    2014-11-01

    Full Text Available Takashi Fujikado,1 Makoto Saika2 1Department of Applied Visual Science, Osaka University Graduate School of Medicine, Osaka, Japan; 2Research and Development Department of Topcon Corporation, Tokyo, Japan Purpose: To examine the effect of misalignment (decentration and tilt of intraocular lenses (IOLs on retinal image quality using a water-immersed model eye with corneal spherical aberration adjusted to the values found in normal human eyes (spherical aberration 0.25 µm; pupil diameter 6 mm.Methods: Three types of IOL holders were prepared. The first was without decentration or tilt, the second had a decentration of 0.5 mm, and the third had a tilt of 5.0°. One spherical IOL and three aspherical IOLs, each with a power of +20 D, were set in the holders and their optical properties (wave front aberration, defocused modulation transfer function, defocused point spread function, and Landolt ring simulations were compared.Results: Coma aberrations generated by misaligned IOLs were related to the spherical aberration corrective power of the IOLs. Landolt ring simulations show that the depth of focus increased as spherical aberration increased and that the retinal image quality was degraded by increases in coma aberration.Conclusion: Coma aberration was generated by IOLs with a large degree of spherical aberration correction, leading to reduced retinal image quality when the IOL was misaligned. This suggests that, in a clinical setting, the quality of vision might be improved by reducing the degree of coma aberration using IOLs that retain, or minimally correct, spherical aberration. Keywords: coma aberration, decentration, misalignment, spherical aberration, tilt

  11. Comparison of clinical outcomes between limbal relaxing incisions and toric intraocular lenses in eyes with astigmatic corneas

    Directory of Open Access Journals (Sweden)

    Giuliano de Oliveira Freitas

    2014-01-01

    Full Text Available Objective: To compare refractive and vectorial outcomes of limbal relaxing incisions (LRI versus toric intraocular lenses (IOL in the treatment of preexisting corneal astigmatism at the time of phacoemulsification. Methods: This longitudinal observational case series assessed 62 eyes of 31 consecutive cataract patients with preoperative corneal astigmatism between 0.75 and 2.50 diopters in both eyes. Patients were randomly assorted in two groups: one assigned to receive AcrySof Toric™ IOL in both eyes, and another one assigned to have AcrySof Natural™ IOL associated with LRI, also in both eyes. All patients were re-evaluated, postoperatively, at 1, 3 and 6 months, when refractive astigmatism analysis was performed using vectorial methods proposed by Thibos. Variability of outcomes within each group and between groups were assessed and compared. Results: Manifest refractive cylinder, in diopters (D, as means ± standard deviation, in the LRI group for 1-month, 3-month and 6-month re-evalutions were respectively -0.66 ± 0.30; -0.70 ± 0.21 and -0.74 ± 0.26 when compared to -0.58 ± 0.24; -0.63 ± 0.20, and -0.62 ± 0.17 in the toric IOL group. (p value ≥ 0.06. Vectorial analysis evidenced greater astigmatism reduction in the toric IOL group in the 6th postoperative month, when postoperative mean astigmatic power vector was 0.31 D, when compared to 0.37 D in the LRI group (p value = 0.00. Conclusions: A trend of slightly better refractive outcomes favoring toric IOL group was seen, although such a trend was not statistically significant. Vectorial analysis, however, suggests that the use of toric IOL may constitute a more advantageous approach in the treatment of pre-existing corneal astigmatism, simultaneously with phacoemulsification.

  12. A stepwise approach for the management of capsular contraction syndrome in hinge-based accommodative intraocular lenses

    Directory of Open Access Journals (Sweden)

    Page TP

    2016-06-01

    Full Text Available Timothy P Page,1 Jeffrey Whitman2 1Department of Ophthalmology, Oakland University William Beaumont School of Medicine, Royal Oak, MI, 2Key-Whitman Eye Center, Dallas, TX, USA Purpose: The aims of this study are to define the various stages of capsular contraction syndrome (CCS and its effect on refractive error with hinge-based accommodating intraocular lenses (IOLs and to describe a systematic approach for the management of the different stages of CCS. Methods: Hinge-based accommodative IOLs function via flexible hinges that vault the optic forward during accommodation. However, it is the flexibility of the IOL that makes it prone to deformation in the event of CCS. The signs of CCS are identified and described as posterior capsular striae, fibrotic bands across the anterior or posterior capsule, and capsule opacification. Various degrees of CCS may affect hinge-based accommodating IOLs in a spectrum from subtle changes in IOL appearance to significant increases in refractive error and loss of uncorrected visual acuity. The signs of CCS and its effect on IOL position and the resulting changes in refractive error are matched to appropriate treatment plans. Results: A surgeon can avoid CCS and manage the condition if familiar with the early signs of CCS. If CCS is identified, yttrium–aluminum–garnet laser capsulotomy should be considered. If moderate CCS occurs, it may be effectively treated with insertion of a capsular tension ring. If CCS is allowed to progress to advanced stages, an IOL exchange may be necessary. Conclusion: Surgeons should be familiar with the stages of CCS and subsequent interventions. The steps outlined in this article help to guide surgeons in the prevention and management of CCS with hinge-based accommodative IOLs in order to provide improved refractive outcomes for patients. Keywords: z-syndrome, pseudophakic tilt, IOL subluxation, CTR, capsular tension ring, capsular fibrosis

  13. Out-of-the-bag intraocular lens dislocation: outcomes of posterior chamber intraocular lens exchange, risk factors, and prevention

    Institute of Scientific and Technical Information of China (English)

    ZHENG Dan-ying; CHEN Li-na; SUN Yi; SHAO Ying-feng; LIANG Jing-li; LIU Yi-zhi

    2010-01-01

    eye, 2.8%) and anterior vitreous cavity (6 eyes, 16.7%) was found in this series. The foldable intraocular lenses (acrylic or silicone) were explanted from 27 eyes (75%) and rigid intraocular lenses (poly methyl methacrylate,PMMA) from 9 eyes (25%). The most common explanted intraocular lens material was single-piece acrylic (13 pieces,36.1%), followed by 3-piece acrylic (9 pieces, 25%), single-piece PMMA (9 pieces, 25%), and 3-piece silicone (5 pieces,13.9%). Uncorrected visual acuity postoperatively improved in 29 eyes (81%), unchanged in 4 eyes (11%), and worsened in 3 eyes (8%) in comparison to that before exchange operation (P=0.006). Best corrected visual acuity tended to improve, but the improvement was not significant (P=0.206). Complications related to lens exchange surgery were mainly intraocular lens redislocation (1 eye), retinal detachment (1 eye), vitreous hemorrhage (1 eye), and cystoid macular edema (1 eye).Conclusions Out-of-the-bag intraocular lens dislocation was mainly caused by posterior capsule rupture during the initial cataract extraction procedure and the foldable lens was the most common dislocated intraocular lens. In most cases, posterior chamber intraocular lens exchange surgery could provide satisfied final visual outcomes.

  14. Improvement of Uveal and Capsular Biocompatibility of Hydrophobic Acrylic Intraocular Lens by Surface Grafting with 2-Methacryloyloxyethyl Phosphorylcholine-Methacrylic Acid Copolymer

    Science.gov (United States)

    Tan, Xuhua; Zhan, Jiezhao; Zhu, Yi; Cao, Ji; Wang, Lin; Liu, Sa; Wang, Yingjun; Liu, Zhenzhen; Qin, Yingyan; Wu, Mingxing; Liu, Yizhi; Ren, Li

    2017-01-01

    Biocompatibility of intraocular lens (IOL) is critical to vision reconstruction after cataract surgery. Foldable hydrophobic acrylic IOL is vulnerable to the adhesion of extracellular matrix proteins and cells, leading to increased incidence of postoperative inflammation and capsule opacification. To increase IOL biocompatibility, we synthesized a hydrophilic copolymer P(MPC-MAA) and grafted the copolymer onto the surface of IOL through air plasma treatment. X-ray photoelectron spectroscopy, atomic force microscopy and static water contact angle were used to characterize chemical changes, topography and hydrophilicity of the IOL surface, respectively. Quartz crystal microbalance with dissipation (QCM-D) showed that P(MPC-MAA) modified IOLs were resistant to protein adsorption. Moreover, P(MPC-MAA) modification inhibited adhesion and proliferation of lens epithelial cells (LECs) in vitro. To analyze uveal and capsular biocompatibility in vivo, we implanted the P(MPC-MAA) modified IOLs into rabbits after phacoemulsification. P(MPC-MAA) modification significantly reduced postoperative inflammation and anterior capsule opacification (ACO), and did not affect posterior capsule opacification (PCO). Collectively, our study suggests that surface modification by P(MPC-MAA) can significantly improve uveal and capsular biocompatibility of hydrophobic acrylic IOL, which could potentially benefit patients with blood-aqueous barrier damage. PMID:28084469

  15. Comparison of posterior capsule opacification at 360-degree square edge hydrophilic and sharp edge hydrophobic acrylic intraocular lens in diabetic patients

    Institute of Scientific and Technical Information of China (English)

    Ling; Bai; Jin; Zhang; Ling; Chen; Ting; Ma; Hou-Cheng; Liang

    2015-01-01

    ·AIM: To compare posterior capsule opacification(PCO)degree and visual functions after phacoemulsification in eyes implanted with 360-degree square edge hydrophilic acrylic intraocular lens(IOL)(570C C-flex, Rayner) and sharp edge hydrophobic acrylic IOL(Sensar AR40 e,AMO) in diabetic patients.· METHODS: Sixty diabetic patients underwent uneventful phacoemulsification and randomly implanted one of the two IOLs. The PCO value was measured by retroillumination photographs and Evaluation of Posterior Capsule Opacification(EPCO) 2000 image-analysis software at 1, 6, 12, and 24 mo after surgery. Visual acuity, and contrast sensitivity in photopic and mesopic conditions were also examined at each follow up time point. The incidence of eye that required Nd:YAG laser posterior capsulotomy were also compared.·RESULTS: There was not any statistically significant difference in PCO scores between Rayner C-flex 570 C group and Sensar AR40 e group at each follow up time point. Visual acuity, Nd:YAG capsulotomy incidence and contrast sensitivity also had no significant difference during the 24 mo follow-up.·CONCLUSION: For diabetic patients, Rayner 570 C Cflex and Sensar AR40 e IOLs are same effective for prevent PCO. The 360-degree square edge design maybe is a good alternative technique to improve PCO prevention.

  16. 亲水性丙烯酸酯人工晶状体植入后的生物相容性和并发症%Hydrophilic acrylic intraocular lens:biocompatibility and complications following implantation

    Institute of Scientific and Technical Information of China (English)

    魏芬; 艾明

    2015-01-01

    BACKGROUND:Hydrophilic acrylic materials with good biocompatibility have been widely used in clinic. However, there are some problems about the biocompatibility and safety of hydrophilic acrylic intraocular lens after long-term clinical application. OBJECTIVE:To discuss the biocompatibility and stability issues and corresponding processing methods after hydrophilic acrylic intraocular lens implantation. METHODS:A computer-based search of Wanfang and PubMed database was performed for articles related to clinical application of hydrophilic acrylic intraocular lens published from 2005 to 2014. The keywords were “hydrophilic acrylic,intraocular lens” in Chinese and English, respectively. A total of 618 articles were initialy retrieved, and finaly 35 articles were included in result analysis. RESULTS AND CONCLUSION:As the hydrophilic acrylic intraocular lens is foldable, a smal incision is required for implantation and the operation is simple that cause less damage to the patients. In addition, the hydrophilic acrylic intraocular lens has poor bacterial and inflammatory cel adhesion, which leads to a low probability of infective endophthalmitis after implantation. But there is a high incidence of posterior capsule opacification as wel as some refractive errors and visual quality problems after implantation. Taken together, to solve these problems depends on the continuous improvements and updates of intraocular lens materials and designs.%背景:亲水性丙烯酸酯材料的生物相容性良好,在临床得到广泛的应用。但随着亲水性丙烯酸酯人工晶状体临床应用的时间延长,其长期的生物相容性及稳定性问题逐渐显现。目的:讨论亲水性丙烯酸酯人工晶状体植入后的生物相容性及稳定性问题和处理方法。方法:应用计算机检索万方数据库及PubMed数据库2005至2014年与亲水性丙烯酸酯人工晶状体临床应用相关的文献,中文检索词为“亲水性丙烯酸酯

  17. 大焦深人工晶体的设计%Design of multi-focus intraocular lenses

    Institute of Scientific and Technical Information of China (English)

    饶丰

    2012-01-01

    运用Zemax光学设计软件构建Liou-Brennan眼模型,设计了增大焦深的非球面、折射型多焦点和衍射型多焦点人工晶体,并用点列图和视锐度分析了所设计的人工晶体的光学质量。对于非球面人工晶体,在3mm瞳孔下,当人眼无球差时,最佳视锐度相当高,但焦深仅为1.4m^-1;当人眼球差为0.4λ时,最佳视锐度可达0.9,焦深达2.2m,同时在整个焦深范围内视觉质量均优越。对于衍射型和折射型多焦点人工晶体,在明视条件下,虽然视远和视近时视觉质量良好,但是中间距离的视锐度〈0.5。衍射型多焦点人工晶体只有81%的光能用于成像,远近焦点能量均分,且与瞳孔大小无关;折射型多焦点人工晶体的远近焦点能量与瞳孔大小相关。设计的人工晶体均能增大人眼的焦深,但各有优缺点,临床上应该酌情选用。%Abstract : The Liou-Brennan eye model is constructed using the optical design software ZEMAX. The Depth of Focus(DOF), extended Intraocular Lenses(IOL) that includes aspherical IOL, refractive muhifocal IOL and diffractive muhifocus IOL are included in the design. The optical performance of the pseudophakic eye for the designed IOLs is analyzed for both the spot diagram and visual acuity. For the pseudophakic eye with a 3 mm pupil, when the spherical aberration is fully corrected by the aspherical IOL, the best visual acuity reaches 1.2 with a DOF of only 1.4 m^1. When the spherical aberration is 0.4λ, the best visual acuity is 0.9 with a DOF as high as 2.2 m-^1. With the implantation of refractive or diffractive muhifocus IOLs, the pseudophakic eye has fairly good distant and near vision, while the intermediate vision is lower than 0. 5. Diffractive muhifocal IOL allows 81% input energy to image and the energy distribution is not affected by the pupil size. The energy distribution of the refractive multifocal IOL is dependent on the pupil

  18. Incidence of posterior capsule opacification following the implantation of a foldable hydrophilic acrylic intraocular lens: a 4 year follow-up study

    Directory of Open Access Journals (Sweden)

    Priscilla de Almeida Jorge

    2014-08-01

    Full Text Available Purpose: To evaluate the incidence of posterior capsule opacification (PCO four years after the implantation of a hydrophilic acrylic intraocular lens (IOL. Methods: Fifty-eight randomly selected eyes from 58 patients were analyzed four years after phacoemulsification and Ioflex IOL implantation. The patients underwent an ophthalmic examination to detect PCO and a detailed medical history was obtained. The patients' charts were reviewed for their corrected distance visual acuity prior to the IOL implantation, as well as for one month postoperatively. The Student's t-test was used for statistical analysis. Results: The mean age of patients without PCO was 74.6 ± 9.5 years, compared to 70.3 ± 15 years in patients with PCO. Four years after surgery, 39 of the 58 eyes (67% had detectable PCO and 24 eyes (41.3% had decreased visual acuity (VA due to PCO. These patients were referred for Nd:YAG laser capsulotomy. Three patients (5.1% had decreased VA due to glaucoma, IOL opacification, or age-related macular degeneration. Twelve eyes (20.7% presented mild PCO with unchanged VA. Systemic arterial hypertension was reported by 45% of the patients, and in 3.5% of these cases this was associated with diabetes mellitus. Conclusion: This study found the incidence of PCO to be 67% four years after phacoemulsification and Ioflex IOL implantation.

  19. Pseudolentogenic astigmatic effect of multifocal intraocular lenses: non-corneal ocular residual astigmatism (N-CORA) as a new parameter in astigmatic change analysis.

    Science.gov (United States)

    Frings, Andreas; Steinberg, Johannes; Druchkiv, Vasyl; Linke, Stephan J; Katz, Toam

    2017-08-01

    This study was initiated to introduce the term non-corneal ocular residual astigmatism (N-CORA) as a new parameter in astigmatic change analysis after implantation of two different types of non-toric, multifocal intraocular lenses (MIOL). Seventy-two eyes from 72 consecutive patients after MIOL surgery were studied in terms of a retrospective, cross-sectional data analysis. Two types of spherical MIOL were used. Surgical technique in all patients was a 2.4-mm incision phacoemulsification, performed by one surgeon. To investigate the magnitude and axis of astigmatic changes, the true corneal astigmatism and Alpins vector method were applied. There were no statistically significant between-group differences related to the preoperative refraction or ocular residual astigmatism (ORA). After surgery, the mean refractive surgically induced astigmatism (RSIA) and the topographic SIA (TSIA) did not differ significantly between the lenses. The magnitude and orientation of ORA and N-CORA changed after surgery. There are no statistically significant differences in postoperative ORA in magnitude or axis when implanting different types of MIOL. The similarity of N-CORA between both MIOL types shows that both diffractive and refractive asymmetric MIOLs with plate haptics have the same pseudolentogenic astigmatic effect which could be presented in terms of the newly introduced parameter N-CORA.

  20. Synthesis and properties of acrylic copolymers for ocular implants

    Science.gov (United States)

    Reboul, Adam C.

    There is a need for flexible polymers with higher refractive index and extended UV absorbing properties for improved intraocular lenses (IOLs). This research was devoted to the synthesis of new acrylic copolymers for foldable IOLs and to studies concerning IOL polymer properties. New polymers were synthesized from phenylated acrylates copolymerized with N-vinyl carbazole derivatives using bulk free radical addition methods. The copolymers had low Tg values, high refractive index, and were flexible. The N-vinyl carbazole derivatives were characterized by NMR and copolymers were characterized by DSC, UV-Vis, and refractometry. New phenothiazine based UV absorbers with high extinction coefficients were also synthesized for incorporation into ocular materials. Patent disclosures on UV absorbers and high refractive index polymers were prepared. A so called "glistening" phenomenon that occurs in all foldable intraocular lenses currently in clinical use is poorly understood and was studied. Research on this microvoid forming behavior included studies and development of methods to inhibit glistening in low Tg acrylic based copolymers. Glistenings were characterized using SEM and optical microscopy. A novel technique for inhibiting glistening was found and a patent disclosure was prepared.

  1. claw intraocular lens

    OpenAIRE

    Gonnermann, Johannes

    2015-01-01

    There is a wide range of alternative fixation techniques of intraocular lenses in the absence of adequate capsular support, such as angle- or iris-supported anterior chamber lenses and intra- / transsclerally-fixated (suture, fibrin glue, etc.) and iris-supported posterior chamber lenses. All procedures have different advantages and disadvantages depending on the anatomical situation and integrity of the capsular bag complex and the neighboring structures such as the iris, sclera and corneal ...

  2. Comparison of Visual Quality after Implantation of Big Bag and Akreos Adapt Intraocular Lenses in Patients with High Myopia

    Institute of Scientific and Technical Information of China (English)

    Shengsheng Ma; Dongjian Zheng; Ling Lin; Fanjian Meng; Yonggang Yuan

    2015-01-01

    Purpose: To compare vision quality following phacoemulsifi-cation cataract extraction and implantation of a Big Bag or Akreos Adapt intraocular lens (IOL) in patients diagnosed with high myopia complicated with cataract. Methods:.This was a randomized prospective control study. The patients with high myopia complicated with cataract , with axial length ≥28 mm,.and corneal astigmatism ≤1D were enrolled and randomly divided into the Big Bag and Akreos Adapt IOL groups. All patients underwent phacoemulsification cataract extraction and lens implantation..At 3 months after surgery,.intraocular high-order aberration was measured by a Tracey-iTrace wavefront aberrometer at a pupil diameter of 5 mm in an absolutely dark room and statistically compared be-tween two groups. The images of the anterior segment of eyes were photographed with a Scheimpflug camera using Penta-cam three-dimensional anterior segment analyzer..The tilt and decentration of the IOL were calculated by Image-pro plus 6.0 imaging analysis software and statistically compared between two groups. Results:.In total,.127 patients (127 eyes),..including 52 males and 75 females, were enrolled in this study. The total high-or-der aberration and coma in the Akreos Adapt group (59 eyes) were significantly higher compared with those in the Big Bag (P0.05). The horizontal and vertical decentration were significantly smaller in the Big Bag lens group than in the Akreos Adapt group (both P0.05). Conclusion:.Both Big Bag and Akreos Adapt IOLs possess relatively good intraocular stability implanted in patients with high myopia. Compared with the Akreos Adapt IOL, the Big Bag IOL presents with smaller intraocular high-order aberra-tion. Coma is the major difference between the two groups.

  3. Comparison of visual outcomes and subjective visual quality after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of apodized diffractive bifocal intraocular lenses

    Science.gov (United States)

    Gundersen, Kjell Gunnar; Potvin, Rick

    2016-01-01

    Purpose To compare the visual acuity (VA) and quality of vision between bilateral implantation of a trifocal intraocular lens (IOL) and blended bifocal IOLs with an intermediate add in the dominant eye and a near add in the nondominant eye. Patients and methods Patients with either trifocal or blended bifocal IOLs implanted were recruited after surgery. Subjects returned for a single diagnostic visit between 3 and 24 months after surgery. VA was tested at various distances, including low-contrast acuity and acuity at their preferred reading distance. A binocular defocus curve was obtained, and subjective visual function and quality of vision were evaluated. Results Twenty-five trifocal subjects and 30 blended bifocal subjects were enrolled. There were no significant differences in low-contrast acuity, preferred reading distance, or acuity at that reading distance. Binocular vision at 4 m, 60 cm, and 40 cm was not statistically significantly different. The trifocal provided statistically significantly better visual acuity (P<0.05) at vergences from −0.5 to −1.5 D (from 2 m to 67 cm viewing distance, P<0.05). There was no statistically significant difference in the near vision subscale scores of the 39-question National Eye Institute Visual Function Questionnaire or the overall scores of the Quality of Vision questionnaire, though significantly more trifocal subjects reported that the observed visual disturbances were “bothersome” (P<0.05). Conclusion Both lens modalities provided subjects with excellent binocular near and distance vision, with similar low rates of visual disturbances and good reported functional vision. The trifocal IOL provided significantly better intermediate VA in the viewing distance range of 2 m to 67 cm, corresponding to viewing things such as a car dashboard or grocery shelf. VA was similar between groups at viewing distances from 60 to 40 cm, corresponding to computer or reading distance. PMID:27274184

  4. Comparison of visual outcomes and subjective visual quality after bilateral implantation of a diffractive trifocal intraocular lens and blended implantation of apodized diffractive bifocal intraocular lenses

    Directory of Open Access Journals (Sweden)

    Gundersen KG

    2016-05-01

    Full Text Available Kjell G Gundersen,1 Rick Potvin21IFocus Øyeklinikk AS, Haugesund, Norway; 2Science in Vision, Akron, NY, USAPurpose: To compare the visual acuity (VA and quality of vision between bilateral implantation of a trifocal intraocular lens (IOL and blended bifocal IOLs with an intermediate add in the dominant eye and a near add in the nondominant eye.Patients and methods: Patients with either trifocal or blended bifocal IOLs implanted were recruited after surgery. Subjects returned for a single diagnostic visit between 3 and 24 months after surgery. VA was tested at various distances, including low-contrast acuity and acuity at their preferred reading distance. A binocular defocus curve was obtained, and subjective visual function and quality of vision were evaluated.Results: Twenty-five trifocal subjects and 30 blended bifocal subjects were enrolled. There were no significant differences in low-contrast acuity, preferred reading distance, or acuity at that reading distance. Binocular vision at 4 m, 60 cm, and 40 cm was not statistically significantly different. The trifocal provided statistically significantly better visual acuity (P<0.05 at vergences from -0.5 to -1.5 D (from 2 m to 67 cm viewing distance, P<0.05. There was no statistically significant difference in the near vision subscale scores of the 39-question National Eye Institute Visual Function Questionnaire or the overall scores of the Quality of Vision questionnaire, though significantly more trifocal subjects reported that the observed visual disturbances were “bothersome” (P<0.05.Conclusion: Both lens modalities provided subjects with excellent binocular near and distance vision, with similar low rates of visual disturbances and good reported functional vision. The trifocal IOL provided significantly better intermediate VA in the viewing distance range of 2 m to 67 cm, corresponding to viewing things such as a car dashboard or grocery shelf. VA was similar between groups at

  5. COMPARISON OF ANTERIOR CHAMBER REACTION WITH SINGLE-PIECE AND THREE-PIECE INTRAOCULAR LENSES IN MANUAL SMALL INCISION CATARACT SURGERY

    Directory of Open Access Journals (Sweden)

    Usha

    2014-11-01

    Full Text Available OBJECTIVES: To study the anterior chamber reaction between single-piece and three-piece intraocular lenses in manual small incision cataract surgery. METHODS: Prospective study done at Mysore Race Club Charitable Eye Hospital. 140 Patients underwent suture less sclerocorneal tunnel cataract surgeries with single-piece or three-piece Polymethylmethacrylate (PMMA intra ocular lenses (3-piece IOL. Accurate Keratometry was done with the help of Bausch and Lomb Keratometer. IOL power was calculated by using SRK (Sanders-Retzlaff-Kraff II formula, with the help of non-immersion, contact type of A-Scan biometry. Single-piece IOLs were inserted in 70 patients. Three-piece IOL inserted in rest of 70 patients. Slit lamp examination for anterior chamber cells was graded according to Hogan system. Aqueous cells were measured by counting within the visible field under Slit lamp, keeping the beam at maximum intensity. Anterior chamber reaction (AC in 1stPostoperative week and at 8 weeks are compared and analyzed by ANOVA statistics. RESULTS: Single piece IOL group had anterior chamber reaction ranging from 1 to 2+ cells i.e., in 97%. In three-piece IOL group, 70%of eyes had 2+ cells and 12.8% had 3± cells. At 8 weeks, single- piece IOL showed either no cells or occasional cells in 98.6% of patients, compared to three –piece IOL group showing in 77%of cases. 23% had 1+ cells in later group. CONCLUSION: Single-piece implanted IOLs had significant less number of cells were seen in anterior chamber from 1 week to 8 weeks as compared to three-piece IOLs.

  6. Visual and optical performance of diffractive multifocal intraocular lenses with different haptic designs: 6 month follow-up.

    Science.gov (United States)

    Wang, Mengmeng; Corpuz, Christine Carole C; Fujiwara, Megumi; Tomita, Minoru

    2014-01-01

    To evaluate and compare the visual acuity outcomes and optical performances of eyes implanted with two diffractive multifocal intraocular lens (IOL) models with either a plate haptic design or a modified-C design. This retrospective study comprised cataract patients who were implanted with either a plate haptic multifocal IOL model (Acriva(UD) Reviol BB MFM 611 [VSY Biotechnology, Amsterdam, the Netherlands], group 1) or a modified-C haptic multifocal IOL model (Acriva(UD) Reviol BB MF 613 [VSY Biotechnology, Amsterdam, the Netherlands], group 2) between June 2012 and May 2013. The 6 month postoperative visual acuity, refraction, defocus curve, contrast sensitivity, and wave-front aberration were evaluated and compared between these eyes, using different IOL models. One hundred fifty-eight eyes of 107 patients were included in this study. Significant improvement in visual acuities and refraction was found in both groups after cataract surgery (P0.05). However, the ocular higher-order aberrations in group 2 were significantly greater than in group 1 (Phaptic design resulted in better optical performances than that with the modified-C haptic design.

  7. Psychophysical Measurements of Luminance Contrast Sensitivity and Color Discrimination with Transparent and Blue-Light Filter Intraocular Lenses.

    Science.gov (United States)

    da Costa, Marcelo Fernandes; Júnior, Augusto Paranhos; Lottenberg, Claudio Luiz; Castro, Leonardo Cunha; Ventura, Dora Fix

    2017-08-09

    The purpose of this study was to measure luminance contrast sensitivity and color vision thresholdfs in normal subjects using a blue light filter lens and transparent intraocular lens material. Monocular luminance grating contrast sensitivity was measured with Psycho for Windows (version 2.36; Cambridge Research Systems) at 3.0, 6.0, 12.0, 20.0, and 30.0 cycles per degree of visual angle (cpd) in 15 normal subjects (eight female), with a mean age of 21.6 years (SD = 3.8 years). Chromatic discrimination was assessed with the Cambridge colour test (CCT) along the protan, deutan, and tritan color confusion axes. Both tests were performed in a darkened room under two situations: with a transparent lens and with blue light filter lens. Subjective impressions were taken by subjects regarding their visual experience under both conditions. No difference was found between the luminance contrast sensitivity measured with transparent and blue light filter. However, 13/15 (87%) of the subjects reported more comfortable vision with the blue filter. In the color vision test, tritan thresholds were significantly higher for the blue filter compared with the transparent filter (p = 0.003). For protan and deutan thresholds no differences were found. Blue-yellow color vision is impaired with the blue light filter, and no impairment occurs with the transparent filter. No significant differences in thresholds were found in the luminance contrast sensitivity comparing the blue light and transparent filters. The impact of short wavelength light filtering on intrinsically photosensitive retinal ganglion cells is also discussed.

  8. Comparison of Phaconit Rollable IOL with Acrylic Foldable IOL.

    Science.gov (United States)

    Parihar, Jks; Vats, D P; Gupta, R P; Bera, T R; Phooken, R; Singh, A

    2007-01-01

    Phaconit or ultra micro incision phacoemulsification cataract surgery involves phacoemulsification through a 0.9 millimetre sleeveless phaco tip and irrigating chopper followed by implantation of a rollable intraocular lens. The procedure leads to negligible astigmatism and faster visual recovery as compared to phacoemulsification with a foldable intraocular lens. This prospective study analysed 80 cases of sub millimetre phaconit surgery with implantation of rollable intraocular lenses(IOL) in 40 cases and acrylic foldable IOL in the remaining 40 cases. Evaluation of efficacy and adaptability of procedure, equipment settings, operative constraints, postoperative complications, keratometric and topographic evaluation of induced astigmatism with visual outcome and patient's rehabilitation were studied. The intraoperative complications were surge/ chamber collapse in 16 (20%), iris chaffing in one and corneal burns in two cases. All cases had an induced astigmatism of less than or equal to ± 0.25 D in four to six weeks after rollable IOL and ± 0.5 D to ± 0.75 D after acrylic IOL implantation. All patients had best-corrected visual acuity of 6/6 by third post operative day. Phaconit with rollable IOL is a perfect blend of surgical skill, application of technology and ultra thin IOL.

  9. The effect of blue-blocking intraocular lenses on circadian biological rhythm: protocol for a randomised controlled trial (CLOCK-IOL colour study).

    Science.gov (United States)

    Nishi, Tomo; Saeki, Keigo; Obayashi, Kenji; Miyata, Kimie; Tone, Nobuhiro; Tsujinaka, Hiroki; Yamashita, Mariko; Masuda, Naonori; Mizusawa, Yutarou; Okamoto, Masahiro; Hasegawa, Taiji; Maruoka, Shinji; Ueda, Tetsuo; Kojima, Masashi; Matsuura, Toyoaki; Kurumatani, Norio; Ogata, Nahoko

    2015-05-12

    Blue light information plays an important role in synchronising internal biological rhythm within the external environment. Circadian misalignment is associated with the increased risk of sleep disturbance, obesity, diabetes mellitus, depression, ischaemic heart disease, stroke and cancer. Meanwhile, blue light causes photochemical damage to the retina, and may be associated with age-related macular degeneration (AMD). At present, clear intraocular lenses (IOLs) and blue-blocking IOLs are both widely used for cataract surgery; there is currently a lack of randomised controlled trials to determine whether clear or blue-blocking IOLs should be used. This randomised controlled trial will recruit 1000 cataract patients and randomly allocate them to receive clear IOLs or blue-blocking IOLs in a ratio of 1:1. The primary outcomes are mortality and the incidence of cardiovascular disease, cancer and AMD. Secondary outcomes are fasting plasma glucose, triglycerides, cholesterol, glycated haemoglobin, sleep quality, daytime sleepiness depressive symptoms, light sensitivity, the circadian rhythm of physical activity, wrist skin temperature and urinary melatonin metabolite. Primary outcomes will be followed until 20 years after surgery, and secondary outcomes will be assessed at baseline and 1 year after surgery. Ethical approval has been obtained from the Institutional Review Board of Nara Medical University (No. 13-032). The findings of this study will be communicated to healthcare professionals, participants and the public through peer-reviewed publications, scientific conferences and the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) home page. UMIN000014680. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  10. Inability to perform posterior segment monitoring by scanning laser ophthalmoscopy or optical coherence tomography with some occlusive intraocular lenses in clinical use.

    Science.gov (United States)

    Yusuf, Imran H; Peirson, Stuart N; Patel, Chetan K

    2012-03-01

    To evaluate whether occlusive intraocular lenses (IOLs) produced by several manufacturers for clinical use equivalently transmit near-infrared (IR) light for scanning laser ophthalmoscopy (SLO) or optical coherence tomography (OCT) imaging. Nuffield Laboratory of Ophthalmology, Oxford University, United Kingdom. Evaluation of diagnostic test or technology. The study evaluated 6 black IOLs of 2 designs: 3 poly(methyl methacrylate) (PMMA) and 3 iris-claw anterior chamber IOLs. Each IOL was placed between a broad-spectrum white light source and a spectroradiometer to generate transmission spectra. Transmission in the near-IR range was examined using an 850 nm light-emitting diode. Scanning laser ophthalmoscopy or OCT imaging using Spectralis spectral-domain SLO or OCT was attempted through occlusive IOLs in a model eye. Artisan iris-claw and MS 612 PMMA occlusive IOLs totally occluded all wavelengths of light, including in the near IR range in which SLO and OCT imaging systems operate. It was not possible to capture SLO or OCT images through the iris-claw and PMMA occlusive IOLs in a model eye. Results suggest the property of near-IR transmission that permits SLO or OCT imaging through occlusive IOLs is restricted to the Morcher range of occlusive IOLs. Patients with non-near IR transmitting IOLs will not be able to receive detailed posterior segment monitoring with SLO or OCT. This finding may have a significant impact on preoperative occlusive IOL selection and the management of current patients with occlusive IOLs. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  11. 亲水性非球面与球面人工晶状体植入术后高阶像差的研究%Higher order aberrations in eyes implanted with aspheric vs spherical hydrophilic intraocular lenses

    Institute of Scientific and Technical Information of China (English)

    Ibrahim Kocak; Faruk Kaya; Hakan Baybora

    2012-01-01

    AIM: To compare the effect of spherical and aspheric hydrophilic intraocular lenses (IOL) on postoperative higher order aberrations (HOA). METHODS: Uneventful phacoemulsification was performed in 78 eyes of 66 patients with implanting either spherical Softec or aspheric Ocuva lenses. Preoperative and postoperative 3rd month aberrometry was performed with Visx Wavescan aberrometer to be compared. RESULTS: There was no statistically significant difference between two groups. Postoperative root-mean-square (RMS) value of HOA: 0.27±0.11 in Softec and 0.28±0.13 in Ocuva group, spherical aberration (SA): 0.11±0.07 in Softec and 0.11±0.08 in Ocuva group. CONCLUSION: Aspheric Ocuva IOL seems not to have an advantage of decreasing postoperative HOA compared to spherical Softec IOL.%目的:比较亲水性球面和非球面人工晶状体(intraocular lenses,IOL)对术后高阶像差(higher order aberrations,HOA)的影响.方法:66例78眼行白内障超声乳化术并顺利植入球面Softec或者非球面Ocuva人工晶状体.术前和术后第3mo使用VISX Wavescan像差计进行像差测量与比较.结果:两组间统计学无显著性差异.术后的高阶像差均方根值(root-mean-square,RMS):Softec组0.27±0.11,Ocuva组0.28±0.13,球面像差(spherical aberration,SA):Softec组0.11±0.07,Ocuva组0.11±0.08.结论:与球面Softec人工晶状体比较,Ocuva非球面人工晶状体似乎没有减少术后高阶像差的优势.

  12. Opaque intraocular lens implantation

    OpenAIRE

    Yusuf IH; Patel CK

    2013-01-01

    Imran H Yusuf, CK Patel The Oxford Eye Hospital, West Wing, John Radcliffe Hospital, Headley Way, Headington, Oxford, United KingdomWe read with great interest the recent article by Lee et al,1 who described their clinical experience with three patients who underwent primary implantation of Morcher (Stuttgart, Germany) occlusive intraocular lenses (IOLs) across a variety of neuro-ophthalmic indications. We hope to offer some further insight into these clinical observations in the context of o...

  13. Progresses of Materials of Intraocular Lenses and their Surface Modification%用于治疗白内障的人工晶体材料及表面修饰研究进展

    Institute of Scientific and Technical Information of China (English)

    牛国光; 朱思全; 郑欲东; 张红斌; 宋黎; 杨槐

    2008-01-01

      The recent development of surface modification and materials of intraocular lenses had been described at detail. The Bio-compatibility of materials surface-modified has been improved and post-operation syndrome reduced after modification. With the advancement of IOL materials, the size of incision would be smaller and IOL would prone to the property of bio-self accommodation.%  从材料角度对人工晶体材料及其表面修饰以及材料的发展做了详细介绍。通过表面改性提高了材料的生物相容性,降低术后并发症。人工晶体材料的发展,使得 IOL 植入手术切口更小,倾向于生理调节。

  14. Anterior segment optical coherence tomography in the assessment of postoperative intraocular lens optic changes.

    Science.gov (United States)

    Werner, Liliana; Michelson, Jennifer; Ollerton, Andrew; Leishman, Lisa; Bodnar, Zachary

    2012-06-01

    To evaluate the use of anterior segment optical coherence tomography (AS-OCT) to assess postoperative intraocular lens (IOL) optic changes. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Intraocular lenses explanted because of various complications were used, including poly(methyl methacrylate) (PMMA) IOLs with snowflake degeneration, hydrophilic acrylic IOLs with calcification, a silicone IOL with calcification from an eye with asteroid hyalosis, and hydrophobic acrylic IOLs explanted because of decentration, subluxation, or uveitis-glaucoma-hyphema syndrome. After gross and light microscopy, the IOLs were examined in the dry and hydrated states using AS-OCT. Selected hydrophilic acrylic IOLs were stained for calcium. In-the-bag IOLs in pseudophakic cadaver eyes were also evaluated by AS-OCT before and after explantation to confirm correspondence with the clinical situation. Intraoptic changes, such as snowflake lesions in PMMA IOLs, calcification in hydrophilic acrylic IOLs, and glistenings in hydrophobic acrylic IOLs, could be imaged by AS-OCT. The method was also helpful in analyzing the location and density. However, in cases of more superficial changes, unless the lesions/deposits were present on the optic surface with an extension to the optic substance of at least 0.1 mm, they could not be clearly differentiated from the overall outline of the IOL surface. Anterior segment OCT may be helpful in assessing the presence, location, and density of intraoptic changes, avoiding a misdiagnosis of IOL opacification and the performance of unnecessary procedures, such as posterior capsulotomy or vitrectomy. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  15. Evaluation of a class of polyurethane materials for intraocular lens manufacturing.

    Science.gov (United States)

    Bozukova, Dimitriya; Bertrand, Virginie; Pagnoulle, Christophe; De Pauw-Gillet, Marie-Claire

    2015-08-01

    Ophthalmic lenses are medical devices with considerable requirements in terms of optical, biomechanical and biological performance. There is limited number of materials used for their manufacturing, comprising mainly silicones and poly(meth)acrylates. This series of publications aims at investigating the applicability of thermoplastic polyurethane elastomers (TPU) for the manufacturing of ophthalmic lenses and examining the properties of the respective devices. This study is related to the synthesis of TPUs with chemical compositions that comprise chemically grafted filters for the hazardous-light. GC-MS, attenuated total reflectance Fourier transform infrared spectroscopy, and UV-vis spectroscopies confirmed the reaction completion and the beneficial effect of the filters on the light transmittance, respectively. Relatively high refractive index of the material was measured and allows for the manufacturing of thinner lenses. The contrast sensitivity determined for a model intraocular lens (IOL) was satisfactory. Few optical defects were, however, present on the model lens prepared by thermoplastic injection molding. The elasticity of the materials was evaluated in view to their potential applicability as foldable IOLs by determining their glass transition temperature and their Young modulus and measuring their shore A. The TPU materials demonstrated more bioadhesive character compared with a benchmark hydrophilic acrylic reference material, which is already used for IOL manufacturing. © 2014 Wiley Periodicals, Inc.

  16. Comparação da análise da frente de onda e da sensibilidade ao contraste em olhos pseudofácicos com implante de lentes intra-oculares esférica e asférica Wavefront analysis and contrast sensitivity comparison between spheric and aspheric intraocular lenses

    Directory of Open Access Journals (Sweden)

    Wilson Takashi Hida

    2008-06-01

    Full Text Available OBJETIVO: Comparar a análise da frente de onda e a sensibilidade de contraste pós-operatórias em pacientes submetidos à facoemulsificação com implante de lentes intra-oculares esféricas num olho e asféricas no olho contralateral. MÉTODOS: Este estudo prospectivo comparativo, randomizado, duplo-cego, incluiu 32 olhos de 16 pacientes. Uma avaliação oftalmológica completa foi realizada durante as visitas antes e depois da cirurgia (no primeiro, terceiro, sétimo, e nonagésimo dias pós-cirúrgicos, que incluiu acuidade visual, teste de sensibilidade ao contraste, aberrometria. Todos exames (menos aberrometr=ia foram feitos monocularmente com pupilas não dilatadas. Os pacientes foram submetidos a facectomia ultra-sônica convencional com implante de uma lente asférica SN60WF num olho e esférica SN60ATno outro. RESULTADOS: A acuidade visual média com a melhor correção foi -0,146 LogMAR no grupo da lente intra-ocular esférica, e -0.165 logMAR no grupo da lente intra-ocular asférica sob condições fotópicas, -0,003 LogMAR sob condições mesópicas. A sensibilidade ao contraste foi semelhante em ambos os grupos tanto em condições fotópicas e mesópicas. Em relação às aberrações ópticas ocorreu uma diferença significativa nas aberrações totais (1,09 ± 0,56 no grupo asférico e 1,52 ± 1,19 no grupo esférico e no componente esférico das aberrações de alta ordem(0,422 ± 0,202 no grupo asférico e 0,124 ± 0,087 no grupo esférico. CONCLUSÃO: As duas lentes intra-oculares promoveram uma excelente visão em situações de alto contraste, e os olhos implantados com a lente asférica tiveram menos aberrações totais e esféricas que aqueles implantados com a lente esférica.PURPOSE: Compare the wavefront and contrast sensitivity of bilateral pseudophakic patients with aspheric in one eye and spheric intraocular lenses in the other. METHODS: This prospective, comparative, randomized study, double masked, included 32

  17. Comparison between OPD-Scan results and visual outcomes of monofocal and multifocal intraocular lenses Comparação dos resultados do OPD-Scan e performance visual das lentes intraoculares monofocal e multifocal

    Directory of Open Access Journals (Sweden)

    Wilson Takashi Hida

    2009-08-01

    Full Text Available PURPOSE: To compare the visual outcome, contrast sensitivity and wavefront analysis of patients that underwent cataract surgery and implantation of AcrySof SN60D3 multifocal intraocular lens with those who received the AcrySof SN60AT monofocal IOL. METHODS: This was a prospective clinical trial of forty eyes that received the multifocal IOL and thirty-two eyes that received the monofocal IOL after phacoemulsification. RESULTS: Values for total and spherical aberrations in the multifocal group were statistically lower than in the monofocal group. In the monofocal group, 75% achieved uncorrected intermediate visual acuities between Jaeger 1 and 6. In the multifocal group, 75% of the eyes achieved more than Jaeger 6. At least 87.5% of the multifocal group and 6.3% of the monofocal group achieved monocular uncorrected near acuity of 20/30 (J2, N5 or better. And 90.0% of the eyes in the multifocal group and 37.5% in the monofocal group achieved an uncorrected near acuity of 20/40 (J3, N6 or better. The mean spherical error was 0.11 D in the multifocal group and -0.18 D in the monofocal group (p=0.0379. The SN60D3 group compared to SN60AT group had low contrast sensitivity (log units with statistically significant differences in 6.0 cpd in photopic conditions (p=0.014 and the SN60D3 group compared to SN60AT group had higher contrast sensitivity (log units under mesopic conditions (p=0.044. CONCLUSION: The multifocal IOLs induced less spherical aberration than monofocal IOLs and predictably good uncorrected distance and uncorrected near acuities. However, contrast sensitivity was lower in the multifocal group.OBJETIVO: Comparar a performance visual, sensibilidade ao contraste e de wavefront com OPD-Scan em pacientes submetidos a cirurgia de facoemulsificação com implante de lente intraocular AcrySof SN60D3 multifocal e AcrySof SA60AT monofocal. MÉTODOS: Quarenta olhos com a lente intraocular multifocal e trinta e dois olhos com a lente intraocular

  18. Biomicroscopia ultra-sônica na avaliação da posição das lentes intra-oculares em uma técnica de fixação escleral Ultrasound biomicroscopy in the assessment of the intraocular lenses positioning in a transscleral fixation technique

    Directory of Open Access Journals (Sweden)

    Raul de Camargo Vianna Filho

    2000-10-01

    Full Text Available Objetivo: Avaliar pela biomicrospia ultra-sônica (UBM o posicionamento, em relação ao sulco ciliar, das alças de lentes intra-oculares (LIO, em uma técnica de fixação escleral, avaliando-se também se dois pontos de fixação são suficientes para que não haja inclinação da parte óptica. Métodos: Dezesseis olhos afácicos foram submetidos a implante LIO por uma mesma técnica de fixação escleral, realizados por um mesmo cirurgião. Um mês após a cirurgia, o posicionamento das alças das LIO foram avaliados pelo UBM, assim como distâncias entre as LIO e córnea. Os resultados foram submetidos a testes estatísticos. Resultados: Das 32 alças fixadas à esclera, oito estavam localizadas no sulco ciliar e 24 fora deste. Não houve diferença estatística nas distâncias entre LIO e córnea para alças posicionadas no sulco ciliar quando comparadas àquelas localizadas fora do sulco. Isto sugere que, além da distância ao limbo que se transfixa a esclera, outros fatores devem estar associados ao posicionamento da alça no sulco ciliar. As medidas LIO -- córnea realizadas na periferia das LIO às 3, 6, 9, e 12 horas foram semelhantes, mostrando que dois pontos de fixação são suficientes para que a LIO não fique inclinada. Conclusões: Outros fatores (por exemplo o ângulo de abertura do corpo ciliar, além da distância ao limbo na qual se transfixa a esclera, são importantes para o posicionamento das alças no sulco ciliar. Dois pontos de fixação são suficientes para que a LIO não apresente inclinação dentro do olho.Purpose: To assess, through ultrasound biomicroscopy (UBM, the positioning of the intraocular lenses (IOL haptics as related to the ciliary sulcus by using a scleral fixation technique; and to evaluate, as well, if two fixation points are sufficient to avoid tilting of the lenses. Methods: Sixteen aphakic eyes underwent an IOL implan-tation by means of the same scleral fixation technique, performed by the

  19. Coated with nanomaterials intraocular lenses, ophthalmic and human body implantable devices with high catalytic antioxidant activities: a new nanotechnology strategy of peroxidase cellular enzyme mimics increasing the biocompatibility and therapeutic deployment of the medical prosthetic device.

    Science.gov (United States)

    Babizhayev, Mark A

    2013-04-01

    While cataract surgery is generally recognized as being one of the safest operations, there is still a significant complication rate. From 30 to 50% of all patients in the United States having cataract extraction develop opacification of the posterior lens capsule within two years and require laser treatment with its own significant risk of complications. Of the patients having cataract surgery, 0.8% develop retinal detachments, from 0.6% to 1.3% were rehospitalized for corneal edema or required corneal transplantation and about 0.1% presented with endophthalmitis . Thus, aside from secondary cataract, about 2% of 1.3 million people, or 26,000 individuals in the United States annually develop serious complications as a result of cataract surgery. The aim of this investigation was to increase the safety and effectiveness of an individual intraocular lens (IOL) preventing an impairment in peroxide metabolism of the mature human cataractous lenses compared to normal lenses employing the specific nanotechnology coating which substitutes the inhibitory effect of the implantable device towards the active species of oxygen and the ability of IOL to regulate the H2O2 and lipid hydroperoxides levels in the surrounding medium. The implantation of IOLs with metabolic activity improves the capability of the surrounding ocular tissues to withstand oxidative stress induced in ocular humors by the photochemical and other metabolic reactions. The coated implantable medical device with thin film of platinum applied with magnetron sputtering, reacts as a body enzyme with deleterious peroxide compounds and free radical oxygen species in body fluids and tissue when said device is implanted into human body. The IOL having haptics coated with thin film of platinum, catalyzes the reduction of peroxide compounds to decrease their levels within the aqueous humor. Further, the coatings also scavenge toxic free radicals of oxygen, thus preventing cellular dysfunction resulting from oxidative

  20. Estudo comparativo do desempenho visual e análise de frente de onda entre as lentes intra-oculares multifocais difrativas Tecnis® ZM900 e AcrySof® ResTor® SN60D3 Comparison between OPD-Scan results and visual outcomes of Tecnis® ZM900 and Restor® SN60D3 diffractive multifocal intraocular lenses

    Directory of Open Access Journals (Sweden)

    Wilson Takashi Hida

    2008-12-01

    Full Text Available OBJETIVOS: Comparar o desempenho visual e a análise de frente de onda entre as lentes intra-oculares (LIOs multifocal difrativa Tecnis® ZM900 asférica e AcrySof® Restor® esférica SN60D3. MÉTODOS: Trata-se de estudo prospectivo comparativo que incluiu 78 olhos de 39 pacientes. A avaliação oftalmológica contou com medida da acuidade visual para longe, intermediária e curta distância, sem correção e com a melhor correção óptica, teste de sensibilidade ao contraste e análise de frente de onda por meio do aberrômetro OPD-Scan. RESULTADOS: Acuidade visual para longe e para perto sem correção óptica e análise de aberrometria foram estatisticamente semelhantes em relação a ambas as LIOs; já a visão intermediária e a sensibilidade ao contraste em condições fotópicas revelaram diferença estatisticamente significante entre as duas lentes a favor da Tecnis ZM900. CONCLUSÃO: Ambas as lentes intra-oculares promoveram excelente visão para longe e para perto em situações de alto contraste. A LIO Tecnis multifocal necessita de menos luminosidade para visão em situações de alto contraste, apresenta menos aberrações ópticas e melhor visão intermediária que a LIO ResTor.PURPOSE: Comparison of the visual performance and wavefront analysis between patients with Tecnis® ZM900 aspheric and AcrySof ReStor® SN60D3 spheric diffractive multifocal intraocular lenses (IOL. METHODS: This prospective comparative study included 78 eyes of 39 patients. The performed ophthalmologic evaluation included near, intermediate and distance corrected and uncorrected visual acuity, contrast sensitivity measurement (under photopic and mesopic conditions and wavefront analysis with the OPD-Scan aberrometrer. RESULTS: Uncorrected near and distance visual acuity and aberrometry analysis were similar with both intraocular lenses; nevertheless, intermediate visual acuity and contrast sensitivity under photopic conditions were statistically better

  1. Intraocular lens fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, M.A.; Foreman, L.R.

    1997-07-08

    This invention describes a method for fabricating an intraocular lens made from clear Teflon{trademark}, Mylar{trademark}, or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube. 13 figs.

  2. Intraocular lens fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, Mike A. (Albuquerque, NM); Foreman, Larry R. (Los Alamos, NM)

    1997-01-01

    This invention describes a method for fabricating an intraocular lens made rom clear Teflon.TM., Mylar.TM., or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube.

  3. Visual and optical performance of diffractive multifocal intraocular lenses with different haptic designs: 6 month follow-up

    Directory of Open Access Journals (Sweden)

    Wang M

    2014-05-01

    Full Text Available Mengmeng Wang,1,* Christine Carole C Corpuz,1 Megumi Fujiwara,1 Minoru Tomita1,2,*1Shinagawa LASIK Center, Tokyo, Japan; 2Department of Ophthalmology, Wenzhou Medical College, Wenzhou, People’s Republic of China*These authors contributed equally to this workPurpose: To evaluate and compare the visual acuity outcomes and optical performances of eyes implanted with two diffractive multifocal intraocular lens (IOL models with either a plate haptic design or a modified-C design.Methods: This retrospective study comprised cataract patients who were implanted with either a plate haptic multifocal IOL model (AcrivaUD Reviol BB MFM 611 [VSY Biotechnology, Amsterdam, the Netherlands], group 1 or a modified-C haptic multifocal IOL model ( AcrivaUD Reviol BB MF 613 [VSY Biotechnology, Amsterdam, the Netherlands], group 2 between June 2012 and May 2013. The 6 month postoperative visual acuity, refraction, defocus curve, contrast sensitivity, and wave-front aberration were evaluated and compared between these eyes, using different IOL models.Results: One hundred fifty-eight eyes of 107 patients were included in this study. Significant improvement in visual acuities and refraction was found in both groups after cataract surgery (P<0.01. The visual acuity and contrast sensitivity were statistically better in group 1 than in group 2 (P<0.01. No statistically significant difference in the corneal higher-order aberrations was found between the two groups (P>0.05. However, the ocular higher-order aberrations in group 2 were significantly greater than in group 1 (P<0.05.Conclusion: At 6 months postoperatively, both AcrivaUD Reviol BB MFM 611 IOL and AcrivaUD Reviol BB MF 613 IOL achieved excellent visual and refractive outcomes. The multifocal IOL model with plate haptic design resulted in better optical performances than that with the modified-C haptic design.Keywords: AcrivaUD, VSY, plate haptic, modified-C haptic, multifocal

  4. The Predictability of Preoperative Pilocarpine-Induced Lens Shift on the Outcomes of Accommodating Intraocular Lenses Implanted in Senile Cataract Patients

    Science.gov (United States)

    Li, Jin; Chen, Qi; Lin, Zhibo; Leng, Lin; Huang, Fang

    2016-01-01

    Purpose. To evaluate the predictability of lens shift induced by pilocarpine (LSPilo) on the outcomes of accommodating intraocular lens (Acc-IOL) implantation. Methods. Twenty-four eyes of 24 senile cataract patients who underwent phacoemulsification and Acc-IOL implantation were enrolled. LSPilo was evaluated with anterior segment optical coherence tomography (AS-OCT). At 3 months postoperatively, the best corrected distance visual acuities (BCDVA), distance-corrected near visual acuities (DCNVA), and subjective and objective accommodations were measured. IOL shifts under accommodation stimulus (IOLSAcc) were evaluated with AS-OCT. Results. The mean LSPilo was 112.29 ± 30.72 µm. LSPilo was not associated with any preoperative parameters. The mean IOLSAcc was 130.46 ± 42.71 µm. The mean subjective and objective accommodation were 1.54 ± 0.39 D and 1.27 ± 0.41 D, respectively. The mean postoperative BCDVA and DCNVA (log MAR value) were 0.22 ± 0.11 and 0.24 ± 0.12, respectively. LSPilo positively correlated with IOLSAcc (r = 0.541; P = 0.006), subjective accommodation (r = 0.412; P = 0.022), and objective accommodation (r = 0.466; P = 0.045), respectively. Conclusion. LSPilo is an independent preoperative parameter associated with the postoperative Acc-IOL mobility and pseudophakic accommodation. It may offer valuable information for ophthalmologists in determining the suitable candidates for Acc-IOL implantation. PMID:27516899

  5. Classification of intraocular lens and its intraocular biocompatibility%人工晶体分类及其在眼内的生物相容性

    Institute of Scientific and Technical Information of China (English)

    胡莉群

    2009-01-01

    目的:通过手术摘除自身浑浊晶体,植入人工晶体是治疗白内障的惟一有效措施.文章总结人工晶体材料的研究进展,为今后的临床应用和研究提供参考.方法:应用计算机检索1997/2009 Medline数据库、中国期刊网和万方数据库、SpringerLink数据库和ScienceDirect数据库.结果:共有25篇文章符合纳入标准.文章主要从人工晶体的发展现状、分类、生物相容性、人工晶体的并发症和发展趋势进行阐述.人工晶体按照硬度,可以分为硬质人工晶体和软性人工晶体.丙烯酸人工晶体比硅凝胶人工晶体的生物相容性更好.人工晶状体脱位是白内障摘除联合人工晶状体植入术后较常见的并发症之一.注入式人工晶体材料是今后研究的方向.结论:人工晶体植入眼内作为一种异物,机体对此产生反应是机体正常的防御现象.人工晶体材料和设计应充分的考虑人工晶体的生物相容性、术后视功能、调节功能、光保护等方面性能.保证术后的疗效和减少并发症的发生,使白内障患者获得更高质量的视力康复.%OBJECTIVE: The sole effective measure for cataract is replaced the epinephelos lens with intraocular lens. So, in this paper, we summarize the research process of intraocular lens, which can provide a reference for further study. METHODS: Medline, China Journal Net, Wanfang Data, SpringerLink, and ScienceDirect database were computer retrieved from 1997 to 2009. RESULTS: A total of 25 papers were included. All the papers were explained intraocular lens from the aspect of current situation, complication following implantation, and develop tendency. According to hardness, intraocular lens can be divided into hard intraocular lens and soft intraocular lens. Acrylic intraocular lenses showed better biocompatibility than the silicone intraocular lenses. In addition, the common complication following implantation was dislocation of lens. Therefore

  6. Sutureless, Glueless, Scleral Fixation of Single-Piece and Toric Intraocular Lens: A Novel Technique.

    Science.gov (United States)

    Kelkar, Aditya; Shah, Rachana; Kelkar, Jai; Kelkar, Shreekant; Arora, Ekta

    2015-01-01

    Sutureless, glueless, scleral fixation of an intraocular lens is a known technique of fixing a lens in the scleral pockets. However, this technique is applied to single-piece and toric lenses instead of 3-piece lenses, allowing the advantage of the use of premium lenses in patients with poor capsular support. Favourable results without complications of pigment dispersion, iris transillumination defects, dysphotopsia, elevated intraocular pressure, intraocular hemorrhage and cystoid macular edema with a well-centered, stable intraocular lens have been observed in the 3-month postoperative period in both cases.

  7. Patient-reported benefit of ReSTOR® multi-focal intraocular lenses after cataract surgery: Results of Principal Component Analysis on clinical trial data

    Directory of Open Access Journals (Sweden)

    Viala Muriel

    2008-01-01

    Full Text Available Abstract Background Restoration of functional distance and near vision independently of additional correction remains a goal for cataract surgery. ReSTOR®, a new multi-focal intraocular lens (IOL addresses this issue with an improvement in both distance and near vision, often without need for glasses. This analysis attempted to discuss the patient-reported benefit of ReSTOR® using a full but organised representation of data. Methods Two non-randomised, open-label clinical trials conducted in Europe and the United-States were conducted to compare the efficacy of ReSTOR® to AcrySof® mono-focal IOLs. A total of 710 patients in need of bilateral cataract extraction were included in the pooled study. The TyPE, a patient questionnaire, was fully completed by 672 of them before and after each eye surgery. The TyPE, composed of 67 items measuring overall visual functioning in both conditions (with and without wearing glasses, evaluates limitations, troubles and satisfaction in distance and near vision. A principal component analysis (PCA of the TyPE questionnaire was performed on pooled data from baseline and post-surgery observations in order to fully represent the change in the TyPE data over time. ReSTOR® and mono-focal groups were used as illustrative variables. The coordinates of the first 2 factors were compared between visits and between IOLs (ReSTOR® vs. mono-focal, using paired t-tests and t-tests, respectively. Results The first factor of the PCA explained 55% of the variance and represented 'visual functioning and patient satisfaction'. The second factor explained 6% of the variance and was interpreted as 'independence from glasses'. An overall difference in factorial coordinates in both factors was seen between baseline and the first eye surgery, and between the first and the second eye surgery. No difference between ReSTOR® and mono-focal IOL groups was observed at baseline. After surgery, ReSTOR® treated-patients had higher

  8. Resultados del implante múltiple de lentes intraoculares en la cirugía de catarata en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer" Results of the multiple intraocular lenses implantation in the cataract surgery performed at "Ramón Pando Ferrer" Cuban Institute of Ophthalmology

    Directory of Open Access Journals (Sweden)

    Eric Montero Díaz

    2010-06-01

    Full Text Available OBJETIVO: Valorar los resultados visuales de los pacientes operados con la técnica de piggy back o implantes múltiples de lentes intraoculares. MÉTODOS: Se realizó un estudio descriptivo retrospectivo de corte transversal en el que se tomaron 32 ojos de 30 pacientes del universo operado de catarata, con la técnica antes descrita, en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer", en el período comprendido entre enero de 2000 hasta diciembre de 2006. Fueron evaluadas algunas variables demográficas, como edad y sexo, así como agudeza visual y refracción preoperatorio y posoperatoria con cristales y sin ellos. Reportamos las complicaciones transquirúrgicas y posquirúrgicas asociadas a las diferentes técnicas quirúrgicas empleadas para la extracción del cristalino. RESULTADOS: La edad promedio obtenida fue mayor de 50 años, y predominó el sexo femenino. Parte de los pacientes tuvieron una agudeza visual corregida superior a 20/40. La complicación más frecuente fue la opacidad de la cápsula posterior y solo en la tercera parte de los pacientes se obtuvo una buena corrección refractiva. CONCLUSIONES: La técnica de piggy back permitió la recuperación de cuatro líneas en la cartilla de Snellen en la agudeza visual corregida, mientras que en la agudeza visual sin corrección solo aumentó en dos líneas. Se encontró igual número de pacientes hipocorregidos y bien corregidos.OBJECTIVE: To asses the visual results of patients operated on by piggy back technique or multiple implantation of intraocular lenses METHODS: A retrospective cross-sectional descriptive study was conducted in 32 eyes from 30 patients operated on from cataract, using the above-mentioned technique, at "Ramon Pando Ferrer" Cuban Institute of Ophthalmology in the period January 2000 through December 2006. Some demographic variables as age and sex as well as visual acuity and preoperative and postoperative refraction with/without lenses were evaluated

  9. Closed intraocular microsurgery in ocular trauma.

    Science.gov (United States)

    Kanski, J J

    1978-04-01

    A series of 53 eyes that had suffered severe trauma was treated by closed intraocular microsurgery with vitreous cutters. The cases were divided into three categories: (a) anterior segment reconstruction for traumatic cataracts and post-traumatic pupillary membranes, (b) vitreous haemorrhage with and without retinal detachment, and (c) traumatically dislocated lenses.

  10. 三片式与一片式人工晶状体囊袋旋转稳定性比较及对高阶像差影响%Comparison of rotational stability between three-piece and one-piece intraocular lenses:effect on high-order aberration

    Institute of Scientific and Technical Information of China (English)

    陈雪红; 汤欣; 宋慧

    2012-01-01

    目的 比较三片式与一片式人工晶状体(intraocular lenses,IOL)不同时间段的囊袋旋转稳定性及研究不同旋转角度下内眼及全眼各高阶像差成分的变化,为散光型IOL的最佳设计提供新思路.方法 临床病例对照研究.对2010年11月至2011年7月在天津眼科医院白内障超声乳化植入IOL 60例患者随机分为两组,A组30例(30只眼),植入三片式疏水性丙烯酸酯IOL AR40e;B组30例(30只眼),植入一片式疏水性丙烯酸酯IOL ZCBOO.术中手术显微镜照相,术后1天、7天及1月裂隙灯后照法采集照片,用图像分析软件联合MB-ruler软件计算IOL襻的旋转度.用iTrace视觉功能分析仪测量术后7天及1月6 mm瞳孔直径内眼及全眼高阶像差成分,再将7天及1月两组IOL眼根据旋转度<3°和3°分组比较内眼及全眼高阶像差成分.结果 术后1月两组UCVA≥0.6、BCVA≥0.8.术后1天与术中夹角比较,A组(t =-0.435,P=0.667),B组(t=-0.336,P=0.739),差异均无统计学意义(P>0.05),体位对旋转度无影响.以术后1天为参考值,7天及1月IOL旋转度A组分别为(2.21±1.45)°和(2.43±1.59)°,B组分别为(1.98±1.20)°和(2.14±1.37)°,两组间不同时间段比较,差异均无统计学意义(P>0.05).术后7天和1月两组IOL内眼球差及全眼总高阶像差、球差差异均有统计学意义(P<0.05),而内眼总高阶像差、彗差和三叶草及全眼彗差、三叶草差异均无统计学意义(P>0.05).在不同旋转角度下,7天和1月两组内眼和全眼高阶像差成分各自比较,差异均无统计学意义(P>0.05).结论 三片式与一片式IOL均有良好囊袋旋转稳定性,一片式更为稳定,更适合设计散光型IOL;两种IOL的旋转度对内眼及全眼高阶像差无影响.%Objective To compare rotational stability in the capsular bag between three-piece and one-piece intraocular lenses (IOL) and study the influence of rotation angle (RA) on the high-order aberrations (HOAs) of

  11. Intraocular Lens Calcifications After (Triple-) Descemet Membrane Endothelial Keratoplasty.

    Science.gov (United States)

    Schrittenlocher, Silvia; Penier, Marius; Schaub, Friederike; Bock, Felix; Cursiefen, Claus; Bachmann, Björn

    2017-07-01

    To identify incidence of and risk factors for calcifications of intraocular lenses (IOLs) after Descemet membrane endothelial keratoplasty (DMEK). Retrospective cohort study. Retrospective review of charts and slit-lamp images of 564 consecutive patients from the prospective Cologne DMEK database who underwent DMEK in pseudophakic eyes or DMEK in combination with cataract surgery (triple-DMEK) between September 3, 2013 and October 30, 2015 at the Department of Ophthalmology, University of Cologne. IOL calcifications after (triple-)DMEK occurred in 14 patients (2.5%). Visual acuities in affected and unaffected eyes were 0.33 ± 0.24 logMAR and 0.16 ± 0.01 logMAR after 3 months (P < .001) as well as 0.28 ± 0.16 logMAR and 0.13 ± 0.08 logMAR (P < .001) after 6 months, respectively. The proportions of triple-DMEK vs DMEK, the use of SF6 gas vs room air for anterior chamber tamponade, and the presence of hydrophilic vs hydrophobic acrylic IOLs were comparable in affected and unaffected eyes. Patients with IOL calcifications had higher rebubbling rates than patients without. Larger pupil diameters at the time of surgery showed a tendency to slightly larger areas of IOL calcifications. IOL calcifications after anterior chamber gas tamponade in DMEK lead to visual impairment and are associated with the number of rebubblings after DMEK. IOL calcifications also occur in hydrophobic acrylic IOLs. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Clinical study of Verisyse phakic iris-fixated intraocular lenses for the correction of severe myopia%有晶状体眼Verisyse虹膜夹持型人工晶状体植入矫正超高度近视

    Institute of Scientific and Technical Information of China (English)

    张素华; 曹伟芳; 赵炬伟; 余黎明; 杨坤

    2014-01-01

    Objective To evaluate the efficacy,safety,stability and predictability of the Verisyse phakic iris-fixated intraocular lens (PIOL) for the correction of severe myopia.Methods In this prospective cohort study,37 patients (65 eyes),aged from 17 to 44 years with severe myopia of-9.00--27.00 D (-18.55±4.19 D),were implanted with Verisyse phakic iris-fixated intraocular lenses from June 2005 to March 2012.Visual acuity,refraction,intraocular pressure,corneal endothelium,Verisyse IOL position,contrast sensitivity,glare sensitivity,surgical complications and poor visual symptoms were observed on 1 day,1 week,1 month,3 months,6 months,1 year,2 years,3 years,and 5 years.Then safety index and efficacy index were obtained from BSCVA and UCVA.Results The mean safety index and efficacy index were better than 1 at most times except at 1 month and 24 months.At 5 years,the mean manifest refraction was within 1 D of the attempted correction in 93% of eyes and within 0.5 D of the attempted correction in 84% of eyes.Near vision and intraocular pressure were not significantly different at 5 years.The mean loss of corneal endothelium was 3.0%±2.5% (0.07%-9.1%).The distance from the corneal endothelium to the PIOL was 2.20±0.15 mm (>2 mm) aud 0.73±0.08 mm (>0.5 mm) from the PIOL to the natural lens.There were statistically significant differences between preoperative and postoperative contrast sensitivity and glare sensitivity.Postoperative complications included 2 eyes with light inflammatory deposits on the PIOL surface,1 eye with an oval pupil and 1 patient (2 eyes) with dislocated PIOLs.More than 80% of eyes had depigmented irises at the attachment sites.Conclusion Verisvse IOL implantation for the correction of severe myopia is effective,safe,stable and predictable.It can be a supplement for corneal refractive surgery but follow-up is still required for the evaluation of long-term results.%目的 探讨有晶状体眼Verisyse虹膜夹持型人工晶状体植

  13. Comparison of visual functions and quality of life with aspheric monofocal intraocular lenses and aspheric multifocal intraocular lenses after bilateral cataract surgery%多焦点人工晶状体和单焦点非球面人工晶状体植入术后患者视功能及生存质量比较

    Institute of Scientific and Technical Information of China (English)

    郭别川; 柯敏; 田朕; 韩芳芳

    2014-01-01

    目的 比较植入多焦点人工晶状体(intraocular lens,IOL)和单焦点非球面IOL对单纯白内障患者术后视功能及生存质量的影响.方法 采用前瞻性和回顾性调查研究,共纳入72例(144眼)老年性白内障患者,均行超声乳化联合IOL植入术,其中20例植入折叠式多焦点IOL(多焦点IOL组),52例植入折叠式单焦点非球面IOL(单焦点IOL组),问卷调查并比较患者术前和术后6个月的视功能及生存质量.结果 术后两组患者总体视功能及生存质量之间的差异均无统计学意义(均为P>0.05),但较术前均有提高,差异均有统计学意义(均为P<0.05).在活动能力、社会交际能力和心理健康方面,单焦点非球面IOL植入后却表现出较为明显的优势,差异均有统计学意义(均为P<0.05);多焦点IOL的术后脱镜率明显高于单焦点非球面IOL(P <0.05);而在术后视功能、生存质量的其他具体方面(与视力有关的日常活动限制、周边视野、感觉适应、立体觉和自理能力),两组之间的差异均无统计学意义(均为P >0.05).结论 单焦点IOL和多焦点IOL在改变视功能和生存质量方面总体效果相同,但多焦点IOL在患者脱镜方面有明显优势,而单焦晶状体在价格上表现出比较明显的优势.

  14. 人工晶体因素对白内障角膜散光患者术后获益的影响%Influence of different intraocular lenses on postoperative benefit of cataract patients with astigmatism

    Institute of Scientific and Technical Information of China (English)

    巨朝娟; 楚妙; 张骞; 林伟

    2015-01-01

    BACKGROUND:Monofocal and multifocal Toric intraocular lens that have been widely used in clinic exhibit xcelent biological and optical characteristics and have good safety and stability after implantation. OBJECTIVE:To compare the outcomes and rotation stability in patients with cataract and astigmatism after implantation of monofocal and multifocal intraocular lens. METHODS:A total of 210 patients with cataract and astigmatism who received phacoemulsification and intraocular lens implantation were included in this study. Of them, 105 patients were assigned to monofocal intraocular lens implantation and the other 105 patients to multifocal intraocular lens implantation. Uncorrected visual acuity, best corrected visual acuity, residual astigmatism were reexamined at 1, 3 weeks and 1 month after surgery. The rotation of Toric intraocular lens was determined. The incidence of complications and spectacles- independent rate were recorded. RESULTS AND CONCLUSION:Visual acuity and residual astigmatism in each group were significantly improved after 1 week of intraocular lens implantation (P < 0.05); furthermore, these two indicators became better over time. Improvement of visual acuity and residual astigmatism in multifocal intraocular lens group was more obvious than that in monofocal intraocular lens group. Postoperative intraocular lens rotation at < 5° occurred in both groups. The intraocular lens rotation degree in multifocal intraocular lens group was higher than that in monofocal intraocular lens group at different time points (P < 0.05). There were no significant differences in incidence of complications and spectacles-independent rates between two groups at 1 month after surgery. These results demonstrate that multifocal Toric intraocular lens provides better visual acuity and residual astigmatism improvement, while monofocal Toric intraocular lens provides better rotation stability.%背景:单焦点与多焦点Toric散光型人工晶体具有良好的生物

  15. Bilateral spontaneous dislocation of posterior chamber intraocular lens in a patient with gyrate atrophy

    Directory of Open Access Journals (Sweden)

    Michael Kinori

    2012-01-01

    Full Text Available We report a patient with gyrate atrophy, a rare metabolic disease, who had bilateral late spontaneous posterior dislocation of in-the-bag posterior chamber intraocular lens (PCIOL. He underwent pars plana vitrectomy, PCIOL retrieval and anterior chamber intraocular lens implantation in both eyes. This report may imply that patients with gyrate atrophy are at risk for spontaneous dislocation of intraocular lenses.

  16. Cluster Lenses

    CERN Document Server

    Kneib, Jean-Paul; 10.1007/s00159-011-0047-3

    2012-01-01

    Clusters of galaxies are the most recently assembled, massive, bound structures in the Universe. As predicted by General Relativity, given their masses, clusters strongly deform space-time in their vicinity. Clusters act as some of the most powerful gravitational lenses in the Universe. Light rays traversing through clusters from distant sources are hence deflected, and the resulting images of these distant objects therefore appear distorted and magnified. Lensing by clusters occurs in two regimes, each with unique observational signatures. The strong lensing regime is characterized by effects readily seen by eye, namely, the production of giant arcs, multiple-images, and arclets. The weak lensing regime is characterized by small deformations in the shapes of background galaxies only detectable statistically. Cluster lenses have been exploited successfully to address several important current questions in cosmology: (i) the study of the lens(es) - understanding cluster mass distributions and issues pertaining...

  17. Interactions of benzalkonium chloride with soft and hard contact lenses

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, J.M.; Cheeks, L.; Green, K. (Medical College of Georgia, Augusta (USA))

    1990-02-01

    We measured the uptake and washout of benzalkonium chloride, using radioactive tracer, by representative hard and soft contact lenses. Uptake by soft contact lenses after 7 days of continuous exposure is high (30 to 56 micrograms/mg of lens weight), with a low percentage of washout in 24 hours (between 0.2% and 1.5% of total uptake). High-water content lenses absorb greater quantities of benzalkonium than do low-water content lenses. Hard lenses take up a much smaller quantity of benzalkonium but release between 30% and 60% of total uptake during washout for 24 hours. Fluorosilicone-acrylate polymer lenses adsorb and release the most preservative, while polymethylmethacrylate lenses (Paragon Optical Inc, Mesa, Ariz) adsorb and release the least. The released benzalkonium from either soft or hard lenses is of a sufficient concentration to be at or above the upper limits of safety.

  18. Binocular clinical comparison study of Tecnis multifocal aspheric and monofocal spherical intraocular lenses%双眼植入Tecnis多焦点和单焦点球面人工晶状体的临床比较研究

    Institute of Scientific and Technical Information of China (English)

    叶盼盼; 姚克; 李霞; 吴炜; 黄晓丹; 俞一波

    2010-01-01

    pseudophakic patients with bilateral implantation of Tecnis multifocal aspheric and conventional monofocal spherical intraocular lenses (IOL). Methods A prospective study of 100 consecutive cases (200 eyes) was conducted. All cataract patients underwent phaocoemulsification were randomized to receive multifocal aspheric IOL ( Tecnis ZM900, AMO, multifocal aspheric group) or conventional spherical IOL ( Akreos Adapt, Bausch&Lomb, monofocal spherical group) . The following investigations were performed to assess the uncorrected and distance-corrected visual acuity of distance, intermediate and near distances, accommodative amplitude, spherical aberrations of total eye, contrast sensitivity, glare sensitivity and near stereoacuity. Patients were surveyed for visual disturbances and lifestyle visual quality. The independent-samples t test waa used to compare the measure data which met normal distribution and the Mann-Whitney U test was used to compare the measure data which didn' t meet. The chi-square test was applied to compare categorical variables. Results The uncorrected and distance-corrected bilateral visual acuity of multifocal aspheric group at 30 cm and 40 cm were 0. 24 ± 0. 12 and 0. 22 ± 0. 11 (logMAR) , better than monofocal spherical group ( Z = - 8. 261, P = 0. 000;Z = -5. 508, P =0.000), but the visual acuity at other distances had no statistical difference between two groups. Patients with multifocal aspheric IOL had significantly higher accommodative amplitude than those with monofcal spherical IOL, improved about 2. 3 - 2. 8 D ( Z= -10. 655, P = 0. 000; Z =- 2. 709, P = 0. 007). Mean spherical aberration of multifocal aspheric group was ( 0. 027 ±0. 160) μm and (0. 006 ±0. 083)μm, significantly lower than that of monofocal spherical group (0. 269 ±0. 161) μm, (0.037 ±0.205) μm at 5 mm and 3 mm pupil diameter(Z= - 8. 815, P = 0. 000; Z = -2. 791, P = 0. 005) . The difference of contrast sensitivity was not significant, but glare sensitivity was higher

  19. Coculture with intraocular lens material-activated macrophages induces an inflammatory phenotype in lens epithelial cells.

    Science.gov (United States)

    Pintwala, Robert; Postnikoff, Cameron; Molladavoodi, Sara; Gorbet, Maud

    2015-03-01

    Cataracts are the leading cause of blindness worldwide, requiring surgical implantation of an intraocular lens. Despite evidence of leukocyte ingress into the postoperative lens, few studies have investigated the leukocyte response to intraocular lens materials. A novel coculture model was developed to examine macrophage activation by hydrophilic acrylic (poly(2-hydroxyethyl methacrylate)) and hydrophobic acrylic (polymethylmethacrylate) commercial intraocular lens. The human monocytic cell line THP-1 was differentiated into macrophages and cocultured with human lens epithelial cell line (HLE-B3) with or without an intraocular lens for one, two, four, or six days. Using flow cytometry and confocal microscopy, expression of the macrophage activation marker CD54 (intercellular adhesion molecule-1) and production of reactive oxygen species via the fluorogenic probe 2',7'-dichlorodihydrofluorescein diacetate were examined in macrophages. α-Smooth muscle actin, a transdifferentiation marker, was characterized in lens epithelial cells. The poly(2-hydroxyethyl methacrylate) intraocular lens prevented adhesion but induced significant macrophage activation (p intraocular lens), while the polymethylmethacrylate intraocular lens enabled adhesion and multinucleated fusion, but induced no significant activation. Coculture with either intraocular lens increased reactive oxygen species production in macrophages after one day (p intraocular lens, with hydrophilic surfaces inducing higher activation than hydrophobic surfaces. These findings provide a new method of inquiry into uveal biocompatibility, specifically through the quantification of cell-surface markers of leukocyte activation.

  20. Fixação iriana de lentes de câmara posterior para o tratamento da afacia Iris fixation of posterior chamber intraocular lenses for the treatment of aphakia

    OpenAIRE

    Ana Luiza Lise Ferreira; Leonardo Verri Paulino; Jose Ricardo Carvalho Lima Rehder

    2009-01-01

    OBJETIVO: avaliar os resultados de uma série de casos de fixação iriana de lentes intra-oculares de câmara posterior para correção de afacia, realizados no setor de catarata da disciplina de Oftalmologia da Faculdade de Medicina do ABC e compará-los a literatura existente. MÉTODOS: estudo prospectivo de oito pacientes afácicos, que apresentavam ausência de suporte capsular adequado e foram submetidos à cirurgia para implante secundário de LIO de câmara posterior com fixação iriana seguindo a ...

  1. Tinting of intraocular lens implants

    Energy Technology Data Exchange (ETDEWEB)

    Zigman, S.

    1982-06-01

    Intraocular lens (IOL) implants of polymethyl methacrylate (PMMA) lack an important yellow pigment useful as a filter in the visual process and in the protection of the retina from short-wavelength radiant energy. The ability to produce a yellow pigment in the PMMA used in IOL implants by exposure to near-ultraviolet (UV) light was tested. It was found that the highly cross-linked material in Copeland lens blanks was tinted slightly because of this exposure. The absorptive properties of lens blanks treated with near-UV light in this way approached that of the absorptive properties of human lenses. This finding shows that it is possible to alter IOL implants simply so as to induce a pale-yellow pigment in them to improve the visual process and to protect the retinas of IOL users.

  2. Calcification of intraocular implant lens surfaces.

    Science.gov (United States)

    Wu, Wenju; Guan, Xiangying; Tang, Ruikang; Hook, Daniel; Yan, Wenyan; Grobe, George; Nancollas, George H

    2004-02-17

    Calcification of octacalcium phosphate [Ca8H2(PO4)6 x 5H2O, OCP] on differently packaged "Ultem" and "Surefold" intraocular implant lens surfaces has been studied in vitro in solutions supersaturated with respect to OCP at pH = 7.10 and 37 degrees C. No mineral deposition was observed on the lenses packaged in Ultem vials even after treatment with behenic acid, one of the fatty acids identified on explanted lenses. Following treatment with behenic acid, nucleation of OCP occurred on the lenses from Surefold vials, which incorporate silicone gaskets; induction periods preceding calcification were about 6 h. No mineralization was found on the lenses in vials with other gasket materials, including polytetrafluoroethylene, fluorocarbon elastomer, and polypropylene. The results of this study indicate that both silicone and fatty acids such as behenic acid play important roles in inducing the in vivo calcification of OCP on IOL lenses; all of the lens treatment steps were necessary for nucleation induction.

  3. Resultados del implante múltiple de lentes intraoculares en la cirugía de catarata en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer" Results of the multiple intraocular lenses implantation in the cataract surgery performed at "Ramón Pando Ferrer" Cuban Institute of Ophthalmology

    OpenAIRE

    Eric Montero Díaz; Armando Capote Cabrera; Eneida Pérez Candelaria; Imalvet Santiesteban García; Alina Pedroso Llanes; Belkys Rodríguez Suárez

    2010-01-01

    OBJETIVO: Valorar los resultados visuales de los pacientes operados con la técnica de piggy back o implantes múltiples de lentes intraoculares. MÉTODOS: Se realizó un estudio descriptivo retrospectivo de corte transversal en el que se tomaron 32 ojos de 30 pacientes del universo operado de catarata, con la técnica antes descrita, en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer", en el período comprendido entre enero de 2000 hasta diciembre de 2006. Fueron evaluadas algunas variable...

  4. The Visual Effects of Intraocular Colored Filters

    Directory of Open Access Journals (Sweden)

    Billy R. Hammond

    2012-01-01

    Full Text Available Modern life is associated with a myriad of visual problems, most notably refractive conditions such as myopia. Human ingenuity has addressed such problems using strategies such as spectacle lenses or surgical correction. There are other visual problems, however, that have been present throughout our evolutionary history and are not as easily solved by simply correcting refractive error. These problems include issues like glare disability and discomfort arising from intraocular scatter, photostress with the associated transient loss in vision that arises from short intense light exposures, or the ability to see objects in the distance through a veil of atmospheric haze. One likely biological solution to these more long-standing problems has been the use of colored intraocular filters. Many species, especially diurnal, incorporate chromophores from numerous sources (e.g., often plant pigments called carotenoids into ocular tissues to improve visual performance outdoors. This review summarizes information on the utility of such filters focusing on chromatic filtering by humans.

  5. Controversies in intraocular lens implantation in pediatric uveitis.

    Science.gov (United States)

    Phatak, Sumita; Lowder, Careen; Pavesio, Carlos

    2016-12-01

    Cataract is one of the most common and visually debilitating complications of pediatric uveitis. It develops as a consequence of chronic inflammation and steroid use and is seen most often in juvenile idiopathic arthritis (JIA)-associated uveitis. Cataract extraction with intraocular lens (IOL) insertion has been carried out with a measure of success in non-uveitic pediatric eyes, but in cases of uveitis, multiple factors affect the final outcome. Chronic inflammation and its sequelae such as band keratopathy, posterior synechiae, and cyclitic membranes make surgical intervention more challenging and outcome less certain. Postoperative complications like increased inflammation, glaucoma, posterior capsular opacification, retrolental membranes, and hypotony may compromise the visual outcome. Early refractive correction is imperative in pediatric eyes to prevent amblyopia. The use of contact lenses and intraocular lenses in pediatric uveitic eyes were fraught with complications in the past. Surgical interventions such as vitreo-lensectomy followed by contact lens fitting and small incision cataract surgery followed by different types of intraocular lenses have been utilized, and many reports have been published, albeit in small patient groups. This review analyzes and discusses the existing literature on intraocular lens implantation in cases of pediatric uveitic cataract surgery.

  6. Intraocular lens explantation or exchange: indications, postoperative interventions, and outcomes

    Directory of Open Access Journals (Sweden)

    Refik Oltulu

    2015-06-01

    Full Text Available ABSTRACT Purpose: To analyze the indications for explantation or exchange of intraocular lenses (IOLs, which were originally implanted for the correction of aphakia during cataract extraction. Methods: All cases that involved intraocular lens explantation or exchange in one institution between January 2008 and December 2014 were analyzed retrospectively. Results: In total, 93 eyes of 93 patients were analyzed. The median time interval between implantation and explantation of the anterior chamber intraocular lenses (AC IOL and posterior chamber intraocular lenses (PC IOL was 83.40 ± 83.14 months (range: 1-276 months and 55.14 ± 39.25 months (range: 1-168 months, respectively. Pseudophakic bullous keratopathy (17 eyes, 38.6% and persistent iritis (12 eyes, 27.8% in the AC IOL group and dislocation or decentration (30 eyes, 61.2% and incorrect IOL power (nine eyes, 18.4% in the PC IOL group were the most common indications for explantation of IOLs. The mean logMAR best corrected visual acuity (BCVA improved significantly from 1.30 preoperatively to 0.62 postoperatively in the PC IOL group (p<0.001 but did not improve significantly in the AC IOL group (p=0.186. Conclusions: The primary indication for IOL explantation or exchange was pseudophakic bullous keratopathy in the AC IOL group and was dislocation or decentration in the PC IOL group. PC IOL explantation or exchange is safe and improves visual acuity.

  7. 改良SRK-T公式预测人工晶状体植入术后散光误差分析%Error prediction analysis of astigmatism after intraocular lenses implantation with modified SRK-T

    Institute of Scientific and Technical Information of China (English)

    涂云海; 俞阿勇; 宥永胜; 高潮; 吴文灿

    2011-01-01

    Objective To evaluate the feasibility and the factors of prediction error of astigmatism after intraocular lens (IOL) implantation by modified SRK-T, and to study the value of modified SRK-T using for toric intraocular lens power calculation. Methods Retrospective case seriesstudy. This study included 68 patients (106 eyes) underwent phacoemulsification during Oct 2007 to June 2008 in Eye hospital of Wenzhou Medical College. The result of the spherical equivalent calculated by SRK-T and modified SRK-T was compared, and the astigmatism error predicted by modified SRK-T and subjective refraction was compared with vector analysis. Influencing factor of modified SRK-T was analyzed with a multivariate linear regression analysis. Results Spherical equivalent calculated by modified SRK-T and SRK-T was equal. The factors of prediction error in J0 was astigmatism of cornea (KS),J0=-0.108-0.102×KS (P=0.034); and in J45 was axial length (L) and average refraction of cornea (K),J45=1.797-0.019×L-0.031×K (P=0.009). Conclusion Modified SRK-T is a good option for toric intraocular lens power calculation. The influencing factors of prediction include Ks, L and K.%目的 评价改良SRK-T公式对球面人工晶状体植入术后预测散光的可行性及其误差的影响因素,以探讨改良SRK-T公式在散光人工晶状体度数计算中的应用价值.方法 回顾性系列病例研究.分析2007年10月至2008年6月行超声乳化白内障摘除联合球面人工晶状体植入术且资料完整的白内障病例68例(106眼).比较改良SRK-T公式与SRK-T公式计算得出的术后预测等效屈光度数之间的差异.矢量分析改良SRK-T公式预测的术后散光度与实际术后散光度之间的差异,并采用多元线性回归分析其影响因素.结果 改良SRK-T公式与SRK-T公式计算得出的术后预测等效屈光度结果完全吻合.矢量分析术后散光预测误差结果示:J0预测误差的因素主要是角膜散光(KS),J0=-0.108-0.102

  8. Gravitational lensing

    CERN Document Server

    Dodelson, Scott

    2017-01-01

    Gravitational lensing is a consequence of general relativity, where the gravitational force due to a massive object bends the paths of light originating from distant objects lying behind it. Using very little general relativity and no higher level mathematics, this text presents the basics of gravitational lensing, focusing on the equations needed to understand the phenomena. It then applies them to a diverse set of topics, including multiply imaged objects, time delays, extrasolar planets, microlensing, cluster masses, galaxy shape measurements, cosmic shear, and lensing of the cosmic microwave background. This approach allows undergraduate students and others to get quickly up to speed on the basics and the important issues. The text will be especially relevant as large surveys such as LSST and Euclid begin to dominate the astronomical landscape. Designed for a one semester course, it is accessible to anyone with two years of undergraduate physics background.

  9. Comparison of shape recovery ratios in various intraocular lens haptics.

    Science.gov (United States)

    Kimura, W; Kimura, T; Sawada, T; Kikuchi, T; Toda, H; Yamada, Y; Nagai, H

    1992-11-01

    Since understanding the mechanical properties of intraocular lens (IOL) haptic materials can minimize decentration after surgery, we have examined shape recovery ratios of various intraocular lens haptics (polypropylene [PP], polyvinylidene fluoride [PVDF], extruded poly(methyl methacrylate) [PMMA]) currently on the market under conditions that approximate clinical use. The results using various Ascon lens-holding forceps and compression tests, during which the lenses were held in a cylindrical holder for seven days, one month, and three months, indicated that PVDF haptics had better shape recovery capability than PP and extruded three-piece PMMA haptics.

  10. Ophthalmic Lenses

    CERN Document Server

    Bhootra, Ajay Kumar

    2009-01-01

    This book is uniquely meant for the ophthalmologists, optometrists and opticians to help the world see better by excellent vision through the services of technicians and clinical principle based ophthalmology so that the management of ocular problems can be done for a better vision . Informs that a wide range of material and design of ophthalmic lenses with innovative developments is available. This book presents comprehensively rich information about the ophthalmic lenses and their dispensing tips . It will be highly useful mainly for the students of optometry and opticians, ophthalmologists,

  11. Phacoemulsification and intraocular lenses implanted for super high myopia combined cataract%超声乳化联合人工晶体植入治疗超高度近视白内障疗效观察

    Institute of Scientific and Technical Information of China (English)

    董立红

    2012-01-01

    目的 观察超声乳化联合人工晶体植入治疗超高度近视白内障的疗效及安全性.方法 60例共98眼超高度近视白内障患者,按眼轴长度分为3组,I组眼轴长度(27.00~29.59)mm 35只眼,Ⅱ组眼轴长度(29.60~32.19)mm 30只眼,Ⅲ组眼轴长度(32.20~34.70)mm 33只眼,均采用超声乳化联合人工晶体植入术治疗.结果 术后3个月最佳校正视力≤0.1者7眼(7.14%),0.2~0.4者19眼(19.39%),≥0.5者72眼(73.47%).其中≥0.5者I组34眼(97.14%),Ⅱ组23眼(76.67%),Ⅲ组15眼(45.45%).结论 超声乳化联合人工晶体植入治疗超高度近视白内障可以充分矫正屈光不正,解除光传导通路障碍,提高视力,手术并发症少,是一种安全、有效的方法.%Objective To observe the therapeutic effect of phacoemulsificafion with intraocular lens ( IOL ) implantation for cataract with hish myopia. Methods Sixty patients ( 98 eyes ) with cataract associated with high myopia received phacoemulsification and IOL implantation. They were divided into 3 groups according to ocular axial length, patients in group I with ocular axial length at 27. 00 ~ 29. 59 mm in 35 eyes, patients in group II with ocular axial length at 29. 60 ~32.19 mm in 30 eyes, and patients in group III with ocular axial length at 32. 20 ~ 34.70 mm in 33 eyes. The visual acuity of patients was examined on preoperative day and three months after operation. Results Postoperative vi-sualacuity:BCVAS0.1 in 7 eyes(7.14% ), 0.2-0.4 in 19 eyes( 19.39% ), SO. 5 in 72 eyes(73.47% ), Among BCVA&0. 5 patient, 34 eyes (97.14% ) in I group, 23 eyes ( 76.67% ) in II group, 15 eyes ( 45.45% ) in 111 group. Conclusion Phacoemulsification with and intraocular lens implantation significantly improves visual acuity in patients with cataract and high myopia.

  12. Acrylate Systemic Contact Dermatitis.

    Science.gov (United States)

    Sauder, Maxwell B; Pratt, Melanie D

    2015-01-01

    Acrylates, the 2012 American Contact Dermatitis Society allergen of the year, are found in a range of products including the absorbent materials within feminine hygiene pads. When fully polymerized, acrylates are nonimmunogenic; however, if not completely cured, the monomers can be potent allergens.A 28-year-old woman is presented, who had her teeth varnished with Isodan (Septodont, Saint-Maur-des-Fossés, France) containing HEMA (2-hydroxyethyl methacrylate) with no initial reaction. Approximately 1 month later, the patient developed a genital dermatitis secondary to her feminine hygiene pads. The initial reaction resolved, but 5 months later, the patient developed a systemic contact dermatitis after receiving a second varnishing.The patient was dramatically patch test positive to many acrylates. This case demonstrates a reaction to likely unpolymerized acrylates within a feminine hygiene pad, as well as broad cross-reactivity or cosensitivity to acrylates, and possibly a systemic contact dermatitis with systemic re-exposure to unpolymerized acrylates.

  13. Bilateral Primary Intraocular Lymphoma

    Directory of Open Access Journals (Sweden)

    Mehrdad Karimi

    2011-01-01

    Full Text Available Purpose: To report a case of bilateral primary intraocular lymphoma. Case report: A 33-year-old man presented with bilateral blurred vision since two years ago. Examination revealed large keratic precipitates, anterior chamber reaction, posterior subcapsular cataracts, and vitreous infiltration. After a short trial of topical and periocular steroids, diagnostic 25-gauge pars plana vitrectomy was performed and cytologic evaluation of the aspirate confirmed a diagnosis of intraocular lymphoma. The patient was subsequently managed with intravitreal methotrexate in both eyes and responded favorably. Central nervous system workup for lymphoma was negative. Conclusion: Primary intraocular lymphoma should be considered in young adults suffering from chronic recalcitrant panuveitis.

  14. Fixação iriana de lentes de câmara posterior para o tratamento da afacia Iris fixation of posterior chamber intraocular lenses for the treatment of aphakia

    Directory of Open Access Journals (Sweden)

    Ana Luiza Lise Ferreira

    2009-10-01

    Full Text Available OBJETIVO: avaliar os resultados de uma série de casos de fixação iriana de lentes intra-oculares de câmara posterior para correção de afacia, realizados no setor de catarata da disciplina de Oftalmologia da Faculdade de Medicina do ABC e compará-los a literatura existente. MÉTODOS: estudo prospectivo de oito pacientes afácicos, que apresentavam ausência de suporte capsular adequado e foram submetidos à cirurgia para implante secundário de LIO de câmara posterior com fixação iriana seguindo a técnica modificada de McCannel. RESULTADOS: sete dos oito pacientes (87,5% que não tiveram complicações cirúrgicas obtiveram melhora na acuidade visual corrigida. Um paciente (12,5% apresentou complicação intra-operatória, evoluindo com ceratopatia bolhosa do pseudofácico. Um paciente (12,5% apresentou glaucoma secundário à dispersão pigmentar. CONCLUSÃO: em nosso estudo a técnica de fixação iriana de câmara posterior se mostrou eficaz e segura para o tratamento da afacia, em concordância com os dados da literatura.PURPOSE: evaluate the results of a case series of iris-sutured posterior chamber IOLs for the correction of aphakia in the cataract sector of the department of Ophthalmology of the ABC School of Medicine and compare them with the existing data. METHODS: prospective study of eight patients who underwent foldable IOL implantation using modified McCannel iris suture fixation for aphakia in the absence of capsule support. RESULTS: seven of eight patients (87,5% without surgical complications improved their best corrected visual acuity. One patient (12,5% with surgical complication developed pseudophakic bullous keratopathy. One patient (12,5% developed secondary glaucoma caused by dispersion syndrome. CONCLUSION: in our study the iris-sutured posterior chamber IOLs prove to be safe and effective in the treatment of aphakia, in accordance with existing data.

  15. Misdiagnosis induced intraocular lens dislocation in anterior megalophthalmos

    Institute of Scientific and Technical Information of China (English)

    WANG Qi-wei; XU Wen; ZHU Ya-nan; LI Jin-yu; ZHANG Li; YAO Ke

    2012-01-01

    Anterior megalophthalmos (AM) is an uncommon developmental anomaly of the anterior segment of the eye with a constellation of findings that includes enlarged cornea,deep anterior chamber,posterior positioning of the iris and lens,iris stroma atrophy,hypoplasia of iris dilator,pupil displacement,large capsular bag,lens subluxation,prematurely cataract and the tendency to retinal detachment.AM,especially when symptoms are mild,is not an easy disease to diagnose.We present 3 AM cases that were misdiagnosed as congenital cataract with weak zonule and megalocornea.Intraocular lenses (IOLs) dislocated after standard cataract surgeries and subsequent surgery (replacing the dislocated IOLs with iris-claw intraocular lenses) achieved satisfactory outcome.Although rare,AM should be included in the differential diagnosis of enlarged cornea and we recommend implanting Artisan lens in AM patients.

  16. Symbolic algebra approach to the calculation of intraocular lens power following cataract surgery

    Science.gov (United States)

    Hjelmstad, David P.; Sayegh, Samir I.

    2013-03-01

    We present a symbolic approach based on matrix methods that allows for the analysis and computation of intraocular lens power following cataract surgery. We extend the basic matrix approach corresponding to paraxial optics to include astigmatism and other aberrations. The symbolic approach allows for a refined analysis of the potential sources of errors ("refractive surprises"). We demonstrate the computation of lens powers including toric lenses that correct for both defocus (myopia, hyperopia) and astigmatism. A specific implementation in Mathematica allows an elegant and powerful method for the design and analysis of these intraocular lenses.

  17. Meta - analysis of clinical randomized controlled trials comparing ReZOOM with ReSTOR multifocal intraocular lenses in cataract surgery%ReZOOM与ReSTOR多焦点人工晶状体应用效果的Meta分析

    Institute of Scientific and Technical Information of China (English)

    邵德望; 杨春燕; 陈威; 王华; 刘兵

    2014-01-01

    AIM: To systematic review the effectiveness of refractive multifocal intraocular lens ( MIOL ) ReZOOM vs diffractive MIOL ReSTOR in the treatment of cataract. METHODS: Randomized controlled trials comparing refractive MIOL ReZOOM with diffractive MIOL ReSTOR were identified by searching CENTRAL, MEDLINE, EMbase, WANFANG MED ONLINE, CMJD, SinoMed, and CNKI. Related journals also were hand-searched. Methodological quality of randomized controlled trials ( RCTs ) was evaluated by simple evaluate method that recommended by the Cochrane Collaboration. Data extracted by two reviewers with designed extraction form. RevMan software ( release 5. 2 ) was used for data management and analysis. RESULTS:A total of 7 trials (846 eyes) were included for systematic review. Subgroup analyses were used according to different model comparison of ReSTOR MIOL. The results showed a significant difference in the mean of the best distance corrected intermediate visual acuity ( BDCIVA) in the ReZOOM MIOL group with WMD=-0.11, 95% CI (-0.16, -0.06) (P CONCLUSION: Patients implanted with ReZOOM MIOL can provide better BDCIVA; patients implanted with ReSTOR MIOL show better UCNVA, are less likely to appear light halo, glare and other visual adverse reactions; correction in spectacles cases, patients implanted with ReZOOM or ReSTOR MIOL have considerable performances in the far and near visual acuity.%方法:计算机检索 CENTRAL、MEDLINE、EMbase、万方医学网数据库、维普中文生物医学期刊全文数据库、中国生物医学文献数据库、中国期刊全文数据库,手工检索相关会议文献,纳入所有ReZOOM与ReSTOR对照的超声乳化白内障吸出联合 IOL 植入的随机对照试验。采用Cochrane系统评价方法,由两名评价员分别提取资料,评价方法学质量后,应用RevMan 5.2软件进行Meta分析。结果:共纳入7个随机对照试验(846眼)。结果显示:裸眼远视力:ReZOOM组与ReSTOR组间差异无统计学意义[WMD=-0

  18. Plasma surface modification of rigid contact lenses decreases bacterial adhesion.

    Science.gov (United States)

    Wang, Yingming; Qian, Xuefeng; Zhang, Xiaofeng; Xia, Wei; Zhong, Lei; Sun, Zhengtai; Xia, Jing

    2013-11-01

    Contact lens safety is an important topic in clinical studies. Corneal infections usually occur because of the use of bacteria-carrying contact lenses. The current study investigated the impact of plasma surface modification on bacterial adherence to rigid contact lenses made of fluorosilicone acrylate materials. Boston XO and XO2 contact lenses were modified using plasma technology (XO-P and XO2-P groups). Untreated lenses were used as controls. Plasma-treated and control lenses were incubated in solutions containing Staphylococcus aureus or Pseudomonas aeruginosa. MTT colorimetry, colony-forming unit counting method, and scanning electron microscopy were used to measure bacterial adhesion. MTT colorimetry measurements showed that the optical density (OD) values of XO-P and XO2-P were significantly lower than those of XO and XO2, respectively, after incubation with S. aureus (P plasma technology in contact lens surface modification.

  19. Clinical significance of phacoemulsification and implantation of negative-power intraocular lenses in patients with super high my-opia and cataract%超声乳化联合负度数人工晶状体植入治疗白内障合并超高度近视

    Institute of Scientific and Technical Information of China (English)

    王剑锋; 李韵倩; 代应辉; 方丽; 郁佳; 王爱莲

    2009-01-01

    Objective To observe the clinical significance of phacoemulsification and implantation of negative-power posterior cham-ber intraocular lenses (IOL) in patients with super high myopia and cataract. Methods 15 cases (26 eyes) with super high myopic cataract were performed with phacoemulsification and negative intraocular lens implantation. Their preoperative corrected vision, axial length, postopera-tive visual acuity, refractive status, refractive error and complications were observed. Patients were followerd 3 to 24 months. Results The mean preoperative axial length was 30.12-35.76 mm. Lens with diopter (D)of-1.00-6.00D were implanted. Postoperative corrected visual acuity achieved 0.2 or better in 20 eyes(76.9%), 0.5 or better in 8 eyes (30.77%). Refractive error within 2.00D were in 22 eyes(84.6%), among them 14 eyes (53.8%) were within an error of 1.00D. No retinal or choroidal detachment was seen. Conclusion Phacoemulsification and implanta-tion of negative-power posterior chamber intraocular lenses (IOL) is safe and effective in patients with super high myopia and cataract. It can correct the refractive errors, meanwhile improve the stability of the tissue in eyeball and reduce the occurrence of retinal detachment.%目的 观察超声乳化白内障吸除联合负度数人工晶状体植入术治疗白内障合并超高度近视的临床疗效.方法 对15例(26眼)白内障合并超高度近视眼患者,施行超声乳化白内障吸除联合负度数人工晶状体植入术,记录术前矫正视力、眼轴长度、屈光度数及其与预期屈光度数的偏差值,观察手术并发症和术后眼部情况.结果 术前眼轴长度30.12~35.76mm,平均为32.45mm.术中均顺利植入人工晶状体,无后囊破裂发生.植入屈光度数为-1.0~-6.0D,术后1周,24眼视力均有不同程度的提高,最佳矫正视力≥0.2共20眼(76.9%),其中≥0.5者共8眼(30.77%).2眼因严重的黄斑区网膜萎缩变性,视力无明显提高.

  20. Comparison of contrast sensitivity and glare contrast sensitivity following implantation of photochromic, blue-light filtering ,and conventional clear intraocular lenses%光变色IOL、蓝光滤过IOL和普通IOL植入术后对比敏感度、眩光对比敏感度对比分析

    Institute of Scientific and Technical Information of China (English)

    陈琛; 韦秋红; 刘超; 杜卫静

    2012-01-01

    Objective To compare contrast sensitivity (CS) and glare CS following implantation of photochromic, blue-light filtering and conventional clear intraocular lenses. Methods Sixty senile cataract patients (60 eyes) were randomly divided into 3 groups according to the type of IOL. Group A was implanted MATRITM 400,group B was implanted Acrysof Natural SN60AT,and group C was implanted LENSTEC SofTec I. The CS and glare CS were measured with CSV-1000E at 3 months after surgery. Results Preoperative best corrected vision were 0. 27 ±0. 10 in group A,0. 27 ± 0. 09 in group B ,0.27 ± 0. 09 in group C, and postoperative best corrected vision were 0. 75 ± 0.08 in group A.0.70 ±0.09 in group B,0.70 ±0.09 in group C. There was no statisticaldifference among three groups preoperatively and postoperatively ( all P > 0. 05). But there were statistical differences in each group about the corrected vision between pre-operation and post-operation (all P 0.05). Compared with CS,the glare CS was improved in group A at each spatial frequency (all P 0.05). The CS curve was at normal value in group A, but lower than that of normal people in group B and group C. Conclusion Photochromic MATRIX? 400 intraocular lens has better visual quality than that with blue-light filtering Acrysof Natural SN60AT or conventional clear intraocular lens LENSTEC SofTec I.%目的 观察光变色人工晶状体( intraocular lens,IOL)、蓝光滤过IOL和普通非蓝光滤过IOL植入术后的对比敏感度( contrast sensitivity,CS)和眩光CS的差异.方法 60例老年性白内障随机分为3组,均行白内障超声乳化吸出联合IOL植入术,分别植入光变色MATRIXTM400型IOL(A组)、Acrysof Nutural SN60AT蓝光滤过IOL(B组)、不具有光线滤过功能的LEN-STEC SofTec Ⅰ普通折叠IOL(C组),术后3个月对3组患者进行最佳矫正视力、CS和眩光CS检查.结果 术前A组最佳矫正视力为0.27±0.10,B组为0.27±0.09,C组为0.27±0.09,术后分别为0.75±0.08、0.70±0

  1. Intraocular Lens Calcification; a Clinicopathologic Report

    Directory of Open Access Journals (Sweden)

    Mozhgan Rezaei-Kanavi

    2009-04-01

    Full Text Available

    PURPOSE: To describe the clinical and pathological features of a case of hydrogel intraocular lens (IOL calcification. CASE REPORT: A 48-year-old man underwent explantation of a single-piece hydrophilic acrylic intraocular lens in his left eye because of decreased visual acuity and milky white opalescence of the IOL. The opacified lens was exchanged uneventfully with a hydrophobic acrylic IOL. Gross examination of the explanted IOL disclosed opacification of the optic and haptics. Full-thickness sections of the lens optic were stained with hematoxylin and eosin (H&E, von Kossa and Gram Tworts'. Microscopic examination of the sections revealed fine and diffuse basophilic granular deposits of variable size within the lens optic parallel to the lens curvature but separated from the surface by a moderately clear zone. The deposits were of high calcium content as evident by dark brown staining with von Kossa. Gram Tworts' staining disclosed no microorganisms. CONCLUSION: This report further contributes to the existing literature on hydrogel IOL calcification.

  2. Pseudophakia and intraocular pressure.

    Science.gov (United States)

    Radius, R L; Schultz, K; Sobocinski, K; Schultz, R O; Easom, H

    1984-06-01

    We studied the change in intraocular pressure in 373 consecutive eyes undergoing cataract extraction with intraocular lens implantation between Jan. 1, 1981, and May 31, 1982. There was a mean increase in intraocular pressure of 0.1 mm Hg following this surgery. This increase, however, was not statistically significant (P greater than .5). There was a mean rise in pressure of 0.8 mm Hg in the eyes undergoing intracapsular surgery and a mean fall in pressure of 0.6 mm Hg in the eyes undergoing extracapsular surgery (P less than .05). The change in pressure was unrelated to age, surgeon, or lens type. The results of a separate analysis of 16 eyes with a preoperative diagnosis of glaucoma and eight eyes with ocular hypertension were similar.

  3. Intraocular lens implantation for the treatment of astigmatism%人工晶状体植入术矫正散光

    Institute of Scientific and Technical Information of China (English)

    施俊廷; 徐雯

    2013-01-01

    Refractive intraocular lens surgery can be used for the treatment of moderate and high regular astigmatism.Refractive intraocular lens surgery includes aphakic intraocular lens surgery and phakic intraocular lens surgery.In phakic intraocular lens surgery two types of intraocular lenses are used:iris-claw intraocular lens and posterior chamber intraocular lens.The purpose of this article is to review current knowledge of surgical treatments of astigmatism with a particular focus on toric implantable collamer lenses.%人工晶状体(IOL)植入术能矫正中、高度规则散光.矫正散光的IOL植入术可分为无晶状体眼及有晶状体眼的环曲面IOL植入两类,其中有晶状体眼的环曲面IOL又可分为虹膜夹持型及后房型.本文旨在介绍IOL矫正散光的手术治疗方法,并着重介绍有晶状体眼植入后房型IOL矫正屈光不正合并散光的治疗技术.

  4. Iris-fixated anterior chamber phakic intraocular lens for myopia moves posteriorly with mydriasis.

    NARCIS (Netherlands)

    Cruysberg, L.P.J.; Doors, M.; Berendschot, T.T.; Brabander, J. De; Webers, C.A.; Nuijts, R.M.

    2009-01-01

    PURPOSE: To elucidate the physiological characteristics of eyes implanted with iris-fixated anterior chamber phakic intraocular lenses (pIOLs), which are increasingly being used for the correction of higher myopic and hyperopic refractive errors. METHODS: In a case series of 20 patients (39 eyes), t

  5. CORRECTION OF HIGH MYOPIA WITH THE WORST MYOPIA CLAW INTRAOCULAR-LENS

    NARCIS (Netherlands)

    LANDESZ, M; WORST, JGF; SIERTSEMA, JV; VANRIJ, G

    1995-01-01

    BACKGROUND: Phakic anterior chamber lenses is one of the modalities used to correct high myopia, We report the initial results of our prospective study on the Worst myopia claw intraocular lens (IOL) that is fixated to the anterior iris, METHODS: We studied 35 eyes in 18 patients with a preoperative

  6. Extended drug delivery by contact lenses for glaucoma therapy.

    Science.gov (United States)

    Peng, Cheng-Chun; Burke, Michael T; Carbia, Blanca E; Plummer, Caryn; Chauhan, Anuj

    2012-08-20

    We combine laboratory-based timolol release studies and in vivo pharmacodynamics studies in beagle dogs to evaluate the efficacy of glaucoma therapy through extended wear contact lenses. Commercial contact lenses cannot provide extended delivery of ophthalmic drugs and so the studies here focused on increasing the release duration of timolol from ACUVUE TruEye contact lenses by incorporating vitamin E diffusion barriers. The efficacy of timolol delivered via extended wear contact lenses was then compared to eye drops in beagle dogs that suffer from spontaneous glaucoma. The lenses were either replaced every 24h or continuously worn for 4 days, and the pharmacodynamics effect of changes in the intraocular pressure (IOP) of timolol from the ACUVUE TruEye contact lenses can be significantly increased by incorporation of vitamin E. The in vivo studies showed that IOP reduction from baseline by pure contact lens on daily basis was comparable with that by eye drops but with only 20% of drug dose, which suggested higher drug bioavailability for contact lenses. In addition, by inclusion of vitamin E into the lenses, the IOP was reduced significantly during the 4-day treatment with continuous wear of lens.

  7. Intraocular lens exchange-removing the optic intact.

    Science.gov (United States)

    Lee, Matthew Hao; Webster, Diane Lesley

    2016-01-01

    Current practice for intraocular lens (IOL) exchange is to cut the optic of the posterior chamber intraocular lens (PCIOL) prior to removing it. Great care must be taken during this maneuver to avoid a posterior capsular tear. Removing the haptics from the fibrosed capsule can also be hazardous, as it may result in zonular stress and dehiscence. A technique is described for performing foldable (one-piece acrylic) IOL removal without cutting the optic. Careful visco-dissection of the haptics with a low viscosity ophthalmic viscosurgical device (OVD) in the fibrosed peripheral capsular tunnel avoids zonular or capsular stress. Internal wound enlargement permits foldable IOL removal in one piece, whilst preserving a self-sealing sutureless corneal wound. This technique may enhance the safety and efficacy of foldable IOL exchange.

  8. Hydroimplantation: foldable intraocular lens implantation without an ophthalmic viscosurgical device.

    Science.gov (United States)

    Tak, Harshul

    2010-03-01

    I describe a technique for implantation of a 1-piece acrylic foldable intraocular lens (IOL) using an irrigation cannula of the phaco machine without using an ophthalmic viscosurgical device (OVD). The irrigating cannula introduced through a side port provides excellent stability and positioning to the eye; if required, the cannula tip is used to guide the leading haptic of the IOL into the capsular bag. The fluid coming from the side port via a bimanual irrigation cannula maintains adequate formation of the capsular bag and anterior chamber while the foldable IOL is inserted. The hydroimplantation technique has the advantage of increased efficiency, reduced surgical time and cost, no need for OVD removal from behind the IOL or for additional instrumentation, no OVD-induced intraocular pressure elevation postoperatively, and no risk of early capsular bag distension syndrome. Copyright 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  9. Intraocular lens exchange-removing the optic intact

    Science.gov (United States)

    Lee, Matthew Hao; Webster, Diane Lesley

    2016-01-01

    Current practice for intraocular lens (IOL) exchange is to cut the optic of the posterior chamber intraocular lens (PCIOL) prior to removing it. Great care must be taken during this maneuver to avoid a posterior capsular tear. Removing the haptics from the fibrosed capsule can also be hazardous, as it may result in zonular stress and dehiscence. A technique is described for performing foldable (one-piece acrylic) IOL removal without cutting the optic. Careful visco-dissection of the haptics with a low viscosity ophthalmic viscosurgical device (OVD) in the fibrosed peripheral capsular tunnel avoids zonular or capsular stress. Internal wound enlargement permits foldable IOL removal in one piece, whilst preserving a self-sealing sutureless corneal wound. This technique may enhance the safety and efficacy of foldable IOL exchange. PMID:27366699

  10. Analysis of intraocular lens surface adhesiveness by atomic force microscopy.

    Science.gov (United States)

    Lombardo, Marco; Carbone, Giovanni; Lombardo, Giuseppe; De Santo, Maria P; Barberi, Riccardo

    2009-07-01

    To analyze intraocular lens (IOL) optic surface adhesiveness using atomic force microscopy (AFM). LiCryL Laboratory, University of Calabria, Rende, Italy. The surface adhesive properties of poly(methyl methacrylate) (PMMA), silicone, hydrophilic acrylic, and hydrophobic acrylic IOLs were evaluated by AFM. Analysis was performed at room temperature (21 degrees C) in a liquid environment using the force-versus-distance mode of a commercial instrument (NanoScope III). Measurements were acquired with rectangular silicon cantilevers of a nominal elastic constant of 10 Newton/m. The nominal value of the tip's radius of curvature was 1 mum, and the scanning speed during the acquisitions ranged from 10 to 400 nm/s. The adhesion force measurements showed different characteristics for the various types of IOLs (Pdevelopment and the interface interactions between the IOL and capsule, the results in this study may bolster the theory of manufacturing more-adhesive materials to prevent PCO.

  11. IOL Implants: Lens Replacement and Cataract Surgery (Intraocular Lenses)

    Science.gov (United States)

    ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center ... Uveitis Focus On Pediatric Ophthalmology Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center ...

  12. Microscopic and spectroscopic investigation of an explanted opacified intraocular lens

    Energy Technology Data Exchange (ETDEWEB)

    Simon, V., E-mail: viosimon@phys.ubbcluj.ro [Babeş-Bolyai University, Faculty of Physics and Interdisciplinary Research Institute on Bio-Nano-Sciences, 400084 Cluj-Napoca (Romania); Radu, T.; Vulpoi, A. [Babeş-Bolyai University, Faculty of Physics and Interdisciplinary Research Institute on Bio-Nano-Sciences, 400084 Cluj-Napoca (Romania); Rosca, C. [Optilens Clinic of Ophthalmology, 400604 Cluj-Napoca (Romania); Eniu, D. [Iuliu Haţieganu University of Medicine and Pharmacy, Department of Molecular Sciences, 400349 Cluj-Napoca (Romania)

    2015-01-15

    Highlights: • Changes on intraocular lens (IOL) surface after implantation. • Partial opacification of IOL central area. • Elemental composition on IOL surface prior to and after implantation. • First XPS depth profiling examination of the opacifying deposits. • Cell-mediated hydroxyapatite structuring. - Abstract: The investigated polymethylmethacrylate intraocular lens explanted an year after implantation presented a fine granularity consisting of ring-like grains of about 15 μm in diameter. In order to evidence the changes occurred on intraocular lens relative to morphology, elemental composition and atomic environments, microscopic and spectroscopic analyses were carried out using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), energy-dispersive X-ray (EDS), and X-ray photoelectron (XPS) spectroscopies. The results revealed that the grains contain hydroxyapatite mineral phase. A protein layer covers the lens both in opacified and transparent zones. The amide II band is like in basal epithelial cells. The shape and size of the grains, and the XPS depth profiling results indicate the possibility of a cell-mediated process involving lens epithelial cells which fagocitated apoptotic epithelial cells, and in which the debris derived from cell necrosis were calcified. To the best of our knowledge, this is the first investigation on explanted intraocular lenses using XPS depth profiling in order to examine the inside of the opacifying deposits.

  13. Phakic Intraocular lens- a review

    OpenAIRE

    Cruz, Francisco Miguel

    2015-01-01

    Introduction: Intraocular refractive procedures with the implantation of a Phakic Intraocular lens have become a safe efficient and predictable alternative for treating high ametropias when the use of corneal photoablative procedures is not possible. The implantation of Phakic intraocular lens preservs the accomodative function,is a reversable refractive procedure, with minimal induction of higher order aberrations compaed with corneal photoablative procedures. Methods: An analytical review o...

  14. Acrylic mechanical bond tests

    Energy Technology Data Exchange (ETDEWEB)

    Wouters, J.M.; Doe, P.J.

    1991-02-01

    The tensile strength of bonded acrylic is tested as a function of bond joint thickness. 0.125 in. thick bond joints were found to posses the maximum strength while the acceptable range of joints varied from 0.063 in. to almost 0.25 in. Such joints are used in the Sudbury Neutrino Observatory.

  15. Hyperbranched urethane-acrylates

    Directory of Open Access Journals (Sweden)

    Tasić Srba

    2004-01-01

    Full Text Available The synthesis, characterization and UV-curing of hyperbranched urethaneacrylates (HB-UA were investigated in this study. They were evaluated as oli-gomers in model UV curable coatings. HB-UAs were synthesized by reaction of an aliphatic hyperbranched polyester of the second generation (HBRG2 and an isocyanate adduct, obtained by the reaction of isophoronediisocyana-te and different hydroxy alkyl acrylates. Their thermal properties and viscosities depend on the degree of modification of HBRG2 and the type of hydroxy alkyl acrylate used. The introduction of a flexible alkoxylated spacer between the HBP core and acrylate end groups reduces steric hindrance by moving the cross linkable acrylate groups away from the HBP core and increase its reactivity. Due to the presence of abstractable H-atoms in the α-position to the ether links, HB-UAs based on poly(ethylene oxide monoacrylate are very reactive and do not show oxygen inhibition. The obtained coatings combine a high cross linking density with flexible segments between the cross links, which results in a good compromise between hardness and flexibility and have the potential to be used in different UV-curing applications.

  16. Eye lens crystallins: a component of intraocular pseudoexfoliative material.

    Science.gov (United States)

    Veromann, Siiri; Sünter, Alar; Juronen, Erkki; Tasa, Gunnar; Panov, Aleksei

    2004-01-01

    Feeding experimental animals (19 pigs) with surplus sucrose and salt (NaCl) caused cataractous changes in lens tissue and triggered the formation of pseudoexfoliative material on the lens capsule. In the control animals (15 pigs) pseudoexfoliative material was absent. The avidin-biotin complex immunohistochemical method was applied to the pseudoexfoliative material obtained from 15 porcine experimental precataractous lenses and 1 spontaneously cataractous eye and revealed crystallins as a component of the intraocular pseudoexfoliative material. To prevent the development of both intraocular pseudoexfoliative material and crystallin-dependent glaucomatous changes in the trabecular meshwork of the eye, it is important to avoid any cataractogenic insult, including surplus sucrose and salt consumption, causing crystallin leakage from the lens. Copyright 2004 S. Karger AG, Basel

  17. Types of Contact Lenses

    Science.gov (United States)

    ... back to top ] Rigid Gas Permeable (RGP) Contact Lenses Rigid gas permeable contact lenses (RGPs) are more durable ... Ortho-K) Orthokeratology, or Ortho-K, is a lens fitting procedure that uses specially designed rigid gas permeable (RGP) contact lenses to change the ...

  18. Clinical observation of foldable intraocular lenses in ciliary sulcus suture fixation with Ultrasound biomicroscope-guided%超声生物显微镜引导下折叠人工晶状体睫状沟缝线固定术临床观察

    Institute of Scientific and Technical Information of China (English)

    王胜男; 吕勇

    2013-01-01

    Objective To evaluate the clinical effectiveness of foldable intraocular lenses in ciliary sulcus suture fixation with ultrasound biomicroscope-guided,for clinical application.Methods This study was performed on 37 eyes in 34 patients who needed a foldable intraocular lens in ciliary sulcus suture fixation surgery.A total of 19 eyes in 18 patients had a ultrasound biomicroscope (UBM) examination to ensure the ciliary sulcus localization before the surgery (Group Ⅰ).A total of 18 eyes in 16 patients didn't have a UBM examination (Group Ⅱ).After the surgery,the visual acuity,contrast sensitivity,UBM were checked up in both groups.The results were analyzed by SPSS17.0 statistical software.Results The mean suture position in group Ⅰ was significantly less than that of the group Ⅱ (P <0.001,t-test).The UBM examination showed that the IOL decentration,the optic tilt and the rate of haptics located in the sulcus were statistically significant between the 2 groups.The uncorrected visual acuity (UCVA) 3 months after operation had statistical significance between the 2 groups.But the best corrected visual acuity (BCVA) and the contrast sensitivity function in 3cpd,6cpd,12cpd and 18cpd spatial frequencies 3 months after operation had no significant difference between the 2 groups.Conclusions The use of UBM can help the surgeon identify the ciliary sulcus more precisely,and reduce the tilt and decentration of the IOL,which is conducive to upgrade the operated effect.%目的 通过对比性临床观察,评价超声生物显微镜(UBM)引导下定位睫状沟,行折叠人工晶状体睫状沟缝线固定术的手术效果,为临床应用提供依据.方法 临床病例对照研究.对2010年4月至2012年1月在郑州大学第一附属医院眼科将34例(37只眼)需行人工晶状体睫状沟缝线固定术的患者按术前应用UBM检查和未用UBM检查分为两组:1组18例19只眼,术前行UBM检查,定位睫状沟在巩膜表面投影位置,

  19. Laser therapy in intraocular tumors

    Science.gov (United States)

    Carstocea, Benone D.; Gafencu, Otilia L.; Apostol, Silvia

    1995-01-01

    Intraocular tumors present special problems of diagnosis and treatment. Diagnostic methods include, in addition to systemic and ophthalmological examinations, ancillary examinations such as transillumination, fluorescein angiography, ultrasonography, radioactive phosphorus uptake test, radiology, computerized tomography, and fine-needle aspiration biopsy with cytological analyses. Previously, enucleation of the involved eye was generally accepted as management of malignant tumors. Improved therapeutic methods such as photocoagulation and better surgical techniques now provide a variety of therapeutical alternatives. This study consists of 21 cases of intraocular tumors that were managed by Argon laser photocoagulation. Four cases were intraocular metastasis and 17 cases were primitive intraocular tumors. Argon laser therapy proved to be totally ineffective for the intraocular metastasis and a very adequate therapy for the primitive tumors. Tumor extirpations (choroidal, cillary body, or iris tumors) using laser lancet proved to be more suitable than classic surgery.

  20. 单眼角膜散光白内障患者不同人工晶状体组合植入的对比研究%Comparison of different combinations of intraocular lenses implantation in cataract patients with unilateral astigmatism

    Institute of Scientific and Technical Information of China (English)

    田芳; 张红; 胡尊霞

    2011-01-01

    Objective To assess binocular visual function after combined implantation of toric and multifocal or monofocal intraocular lenses in unilateral astigmatism cataract patients. Methods This was a prospective case control study. A total of thirty unilateral astigmatism patients undergoing phacoemulsification were recruited. AcrySof Toric IOL were implanted in the astigmatic eye of patients, with ReSTOR (15 eyes) or AcrySof IQ (15 eyes) in the contralateral eye. Six months postoperatively, patients were assessed for visual acuity (5.0 m, 60.0 cm, 40.0 cm), contrast sensitivity, amplitude of accommodation, and stereoacuity. Patients were surveyed for visual disturbances and lifestyle visual quality. Data were analyzed with a paired t test, an independent samples t test, or chi-square test. Results At 6 months postoperatively, for Toric-ReSTOR patients, uncorrected binocular logMAR visual acuity at 5.0 m, 60.0 cm, 40.0 cm was 0.05±0.05, 0.24±0.10, and 0.14±0.06, respectively. For Toric-AcrySof IQ patients, uncorrected binocular logMAR visual acuity was 0.06±0.07, 0.26±0.08, and 0.37 ±0.10, respectively. These values between the two group did not achieve significant differences except for near visual acuity (t=5.476, P=0.000). The contrast sensitivity for ReSTOR eyes was lower at 18 cpd under photopic and photopic glare circumstance than for the AcrySof IQ eyes (0.30 ± 0.37 versus 0.94 ±0.58, t=3.476, P=0.001; 0.34 ± 0.44 versus 0.88 ±0.52, t =2.975, P= 0.006). And was lower at 12 cpd under scotopic and scotopic glare circumstance than for the AcrySof IQ eyes (0.05±0.22 versus 0.50±0.61, t=3.057, P=0.005; 0.05±0.22 versus 0.59±0.75, t=3.154, P=0.004). The amplitude curve of accommodation in Toric-ReSTOR patients had two wave peak (0 and-2.5 D), but only one (0 D) in Toric-AcrySof IQ patients. The stereopsis of Toric-ReSTOR eyes decreased slightly (53% versus 73%, x2=1.262, P=0.263). Patient satisfaction for mean near vision was significantly different: 80

  1. Specific features of measuring the optical power of artificial refractive and diffractive-refractive eye lenses

    Science.gov (United States)

    Lenkova, G. A.

    2016-08-01

    Methods for monitoring the optical power of artificial refractive eye lenses (intraocular lenses) based on measuring focal lengths in air and in medium are analyzed. The methods for determining the refraction of diffractive-refractive lenses (in particular, of MIOL-Akkord type), with allowance for the specific features of the diffractive structure, are considered. A computer simulation of the measurement of the focal length of MIOL-Akkord lenses is performed. The effective optical power of the diffractive component of these lenses is shown to depend on the diaphragm diameter. The optimal diaphragm diameter, at which spherical aberrations do not affect the position of foci, is found to be 3 mm. Possible errors in measuring the focal lengths are analyzed, and the necessary corrections that must be introduced into measurement results and calculations of refractions are determined.

  2. Opacificação tardia de lente intra-ocular de polimetilmetacrilato (PMMA: relato de caso Late opacification of a polymethylmethacrylate (PMMA intraocular lens: case report

    Directory of Open Access Journals (Sweden)

    Otacílio de Oliveira Maia Júnior

    2005-10-01

    Full Text Available O implante das lentes intra-oculares foi grande avanço na reabilitação visual de pacientes submetidos à cirurgia de extração da catarata. Contudo, os materiais utilizados na fabricação destas lentes, apesar de terem boa biocompatibilidade, são passíveis de alterações posteriores ao implante. No presente estudo, os autores relatam um caso raro de opacificação tardia de lente de polimetilmetacrilato, material inerte e bem tolerado intra-ocularmente, discutindo aspectos importantes no manejo desta complicação, bem como indicação de explante e substituição da lente.The use of intraocular lenses was a great advance in visual recovery after cataract surgery. Although usually with good biocompatibility, some alterations in the intraocular lens material may occur after implantation. Polymethylmethacrylate was the first intraocular lens material to be used on a large scale and assumed to be inert and well-tolerated. We present a rare case of late opacification of a polymethylmethacrylate lens, discussing important aspects of its management such as the indication for intraocular lens exchange.

  3. Applications of polymers in intraocular drug delivery systems

    Science.gov (United States)

    Alhalafi, Ali Mohammed

    2017-01-01

    We are entering a new era of ophthalmic pharmacology where new drugs are rapidly being developed for the treatment of anterior and posterior segment of the eye disease. The pharmacokinetics of drug delivery to the eye remains a very active area of ophthalmic research. Intraocular drug delivery systems allow the release of the drug, bypassing the blood-ocular barrier. The main advantage of these preparations is that they can release the drug over a long time with one single administration. These pharmaceutical systems are of great important in the treatment of the posterior segment diseases, and they can be prepared from biodegradable or nonbiodegradable polymers. Biodegradable polymers have the advantage of disappearing from the site of action after releasing the drug. The majority of intraocular devices are prepared from nonbiodegradable polymers, and they can release controlled amounts of drugs for months. Nonbiodegradable polymers include silicone, polyvinyl alcohol, and ethylene-vinyl acetate. The polymers usually employed to prepare nanoparticles for the topical ophthalmic route are poly (acrylic acid) derivatives (polyalquilcyanocrylates), albumin, poly-ε-caprolactone, and chitosan. Dendrimers are a recent class of polymeric materials with unique nanostructure which has been studied to discover their role in the delivery of therapeutics and imaging agents. Hydrogels are polymers that can swell in aqueous solvent system, and they hold the solvents in a swollen cross-linked gel for delivery. This review exhibits the current literature regarding applications of polymers in ophthalmic drug delivery systems including pharmacokinetics, advantages, disadvantages, and indications aimed to obtain successful eye therapy. Method of Literature Search: A systematic literature review was performed using PubMed databases into two steps. The first step was oriented to classification of intraocular polymers implants focusing on their advantages and disadvantages. The second

  4. Applications of polymers in intraocular drug delivery systems

    Directory of Open Access Journals (Sweden)

    Ali Mohammed Alhalafi

    2017-01-01

    Full Text Available We are entering a new era of ophthalmic pharmacology where new drugs are rapidly being developed for the treatment of anterior and posterior segment of the eye disease. The pharmacokinetics of drug delivery to the eye remains a very active area of ophthalmic research. Intraocular drug delivery systems allow the release of the drug, bypassing the blood–ocular barrier. The main advantage of these preparations is that they can release the drug over a long time with one single administration. These pharmaceutical systems are of great important in the treatment of the posterior segment diseases, and they can be prepared from biodegradable or nonbiodegradable polymers. Biodegradable polymers have the advantage of disappearing from the site of action after releasing the drug. The majority of intraocular devices are prepared from nonbiodegradable polymers, and they can release controlled amounts of drugs for months. Nonbiodegradable polymers include silicone, polyvinyl alcohol, and ethylene-vinyl acetate. The polymers usually employed to prepare nanoparticles for the topical ophthalmic route are poly (acrylic acid derivatives (polyalquilcyanocrylates, albumin, poly-μ-caprolactone, and chitosan. Dendrimers are a recent class of polymeric materials with unique nanostructure which has been studied to discover their role in the delivery of therapeutics and imaging agents. Hydrogels are polymers that can swell in aqueous solvent system, and they hold the solvents in a swollen cross-linked gel for delivery. This review exhibits the current literature regarding applications of polymers in ophthalmic drug delivery systems including pharmacokinetics, advantages, disadvantages, and indications aimed to obtain successful eye therapy. Method of Literature Search: A systematic literature review was performed using PubMed databases into two steps. The first step was oriented to classification of intraocular polymers implants focusing on their advantages and

  5. Microscopic and spectroscopic investigation of an explanted opacified intraocular lens

    Science.gov (United States)

    Simon, V.; Radu, T.; Vulpoi, A.; Rosca, C.; Eniu, D.

    2015-01-01

    The investigated polymethylmethacrylate intraocular lens explanted an year after implantation presented a fine granularity consisting of ring-like grains of about 15 μm in diameter. In order to evidence the changes occurred on intraocular lens relative to morphology, elemental composition and atomic environments, microscopic and spectroscopic analyses were carried out using scanning electron microscopy (SEM), Fourier transform infrared (FTIR), energy-dispersive X-ray (EDS), and X-ray photoelectron (XPS) spectroscopies. The results revealed that the grains contain hydroxyapatite mineral phase. A protein layer covers the lens both in opacified and transparent zones. The amide II band is like in basal epithelial cells. The shape and size of the grains, and the XPS depth profiling results indicate the possibility of a cell-mediated process involving lens epithelial cells which fagocitated apoptotic epithelial cells, and in which the debris derived from cell necrosis were calcified. To the best of our knowledge, this is the first investigation on explanted intraocular lenses using XPS depth profiling in order to examine the inside of the opacifying deposits.

  6. [Acrylic resin removable partial dentures

    NARCIS (Netherlands)

    Baat, C. de; Witter, D.J.; Creugers, N.H.J.

    2011-01-01

    An acrylic resin removable partial denture is distinguished from other types of removable partial dentures by an all-acrylic resin base which is, in principle, solely supported by the edentulous regions of the tooth arch and in the maxilla also by the hard palate. When compared to the other types of

  7. Laser-triggered intraocular implant to induce photodynamic therapy for posterior capsule opacification prevention.

    Science.gov (United States)

    Zhang, Zhaoguo; Huang, Wenyong; Lei, Ming; He, Yuanfeng; Yan, Mina; Zhang, Xuefei; Zhao, Chunshun

    2016-02-10

    Posterior capsule opacification (PCO) is one of the main reasons for loss of vision again after cataract surgery. In this study, intraocular lenses were modified with indocyanine green (ICG) and sealed up with PLGA to form long-term intraocular implants (ICG-IOL). When triggered by laser, ICG-IOL would induce photodynamic therapy (PDT). In-vitro cell viability assay and scratch wound healing assay demonstrated that ICG-IOL could effectively inhibit HLEpiC proliferation and migration without causing damage to the cells far away from it. Laser attenuation test indicated that ICG-IOL could be applied in vivo. In-vivo pharmacodynamics and safety study showed that ICG-IOL could significantly prevent the occurrence of PCO and was safe for intraocular normal tissue. All these results suggested that ICG-IOL would be a very promising candidate for PCO prevention.

  8. One Episode, Two Lenses

    Science.gov (United States)

    Drijvers, Paul; Godino, Juan D.; Font, Vicenc; Trouche, Luc

    2013-01-01

    A deep understanding of students' learning processes is one of the core challenges of research in mathematics education. To achieve this, different theoretical lenses are available. The question is how these different lenses compare and contrast, and how they can be coordinated and combined to provide a more comprehensive view on the topic of…

  9. On conformal lenses

    CERN Document Server

    Chen, Huanyang; Li, Hui

    2011-01-01

    Plane mirror can make one object into two for observers on the object's side. Yet, there seems no way to achieve the same effect for observers from all directions. In this letter, we will design a new class of gradient index lenses from multivalued optical conformal mapping. We shall call them the conformal lenses. Such lenses can transform one source into two (or even many) omnidirectionally. Like the overlapped illusion optics does, they can even transform multiple sources into one. Rather than using negative index materials, implementation here only needs isotropic positive index materials like other gradient index lenses. One obvious drawback however, is that they have singular permittivity values which restrict them to functioning at one single frequency. This however, needs not be the case when applying transmutation methods, which enable the lenses to work in a broadband frequency range.

  10. Aspherics in spectacle lenses

    Science.gov (United States)

    Dürsteler, Juan Carlos

    2016-12-01

    A review of the use of aspherics in the last decades, understood in a broad sense as encompassing single-vision lenses with conicoid surfaces and free-form and progressive addition lenses (PALs) as well, is provided. The appearance of conicoid surfaces to correct aphakia and later to provide thinner and more aesthetically appealing plus lenses and the introduction of PALs and free-form surfaces have shaped the advances in spectacle lenses in the last three decades. This document basically considers the main target optical aberrations, the idiosyncrasy of single lenses for correction of refractive errors and the restrictions and particularities of PAL design and their links to science vision and perception.

  11. Surgical management of intraocular lens dislocations

    Directory of Open Access Journals (Sweden)

    Adem Gul

    2015-10-01

    Full Text Available ABSTRACTPurpose:To report and compare the surgical, visual, and anatomical outcomes following treatment of dislocated intraocular lenses (IOLs.Methods:The medical records of 28 eyes of 28 patients were evaluated. Age, gender, pre-and postoperative best-corrected visual acuity (BCVA, surgical methods, and complications were recorded.Results:Pre-and postoperative BCVA ranged from counting fingers to 20/32 and from counting fingers to 20/25, respectively. Late-onset dislocations were the most frequently observed complication. The most frequent surgical method was IOL repositioning in 15 of 28 patients, followed by IOL exchange in 11 patients, and IOL removal in 2 patients. Only 1 patient required surgical re-intervention with IOL capture.Conclusions:Visual acuity improved following the use of either IOL repositioning or IOL exchange. No superiority of one method over the other was observed. In the present retrospective case series, management of dislocated IOLs with repositioning or exchange of the primary implant conferred comparable surgical and visual outcomes.

  12. Acrylic Acid and Esters Will Be Oversupply

    Institute of Scientific and Technical Information of China (English)

    Zheng Chengwang

    2007-01-01

    @@ Drastic capacity growth The production capacity of acrylic acid in China has grown drastically in recent years. With the completion of the 80 thousand t/a acrylic acid and 130 thous and t/a acrylic ester project in Shenyang Paraffin Chemical Industrial Co., Ltd., (CCR2006,No. 31) the capacity of acrylic acid in China has reached 882 thousand t/a.

  13. Comparison study of visual function and patient satisfaction in patients with monovision and patients with bilateral multifocal intraocular lenses%双眼植入多焦点人工晶状体与单眼视设计术后视功能及满意度的比较

    Institute of Scientific and Technical Information of China (English)

    穆晶; 陈晖; 李一壮

    2014-01-01

    multifocal intraocular lenses (IOL) and patients with monofocal IOL monovision.Methods Prospective nonrandomized controlled study.This study comprised consecutive bilateral cataract patients 45 cases(90eyes) between January 2011 and March 2012.All cases were divided into two groups:multifocal IOL group(23 patients) having implantation of AcrySof ReSTOR +3D(SN6AD1) multifocal IOL,monovision group(22 patients) having implantation of AcrySof IQ (SN60WF) IOL.Parameters analyzed 3 months postoperatively included binocular uncorrected distance,intermediate,and near visual acuities; stereo vision;photopic and mesopic contrast sensitivity function without glare.Parameters analyzed 6 months postoperatively included spectacle independence; subjective visual symptoms; and patient satisfaction.The independent-samples t test were used to compare the measure data which met normal distribution.The chisquare test was applied to compare categorical variables.Results There were no significant differences between groups in bilateral uncorrected distance vision(0.13 ±0.06,0.17 ±0.19;Z =1.755,P =0.086),intermediate(0.34-0.05,0.33 ±0.06;Z =-0.821,P =0.416),and near vision (0.35 ±0.06,0.41 ± 0.09 ;Z =2.117,P =0.051).There were significant differences between groups in stereo vision (Median:150",525" ;Z =-2.092,P =0.036).Percentage of patients wearing spectacle were less than 10% in all groups [91.3% (21/23),90.9% (20/22)].On the questionnaire,patients in multifocal IOL group complained with double vision,trouble in night vision and halo(21.7%).Conclusions Pseudophakic monovision and MIOL achieved distance vision,intermediate vision and near vision.But monovision was no risk for disturbing visual symptoms associated with multifocal IOL.

  14. [The growth behavior of mouse fibroblasts on intraocular lens surface of various silicone and PMMA materials].

    Science.gov (United States)

    Kammann, J; Kreiner, C F; Kaden, P

    1994-08-01

    Experience with intraocular lenses (IOL) made of PMMA dates back ca. 40 years, while silicone IOLs have been in use for only about 10 years. The biocompatibility of PMMA and silicone caoutchouc was tested in a comparative study investigating the growth of mouse fibroblasts on different IOL materials. Spectrophotometric determination of protein synthesis and liquid scintillation counting of DNA synthesis were carried out. The spreading of cells was planimetrically determined, and the DNA synthesis of individual cells in direct contact with the test sample was tested. The results showed that the biocompatibility of silicone lenses made of purified caoutchouc is comparable with that of PMMA lenses; there is no statistically significant difference. However, impurities arising during material synthesis result in a statistically significant inhibition of cell growth on the IOL surfaces.

  15. Two decades of occupational (meth)acrylate patch test results and focus on isobornyl acrylate

    NARCIS (Netherlands)

    Christoffers, Wietske A; Coenraads, Pieter Jan; Schuttelaar, Marie-Louise A

    2013-01-01

    BACKGROUND: Acrylates constitute an important cause of occupational contact dermatitis. Isobornyl acrylate sensitization has been reported in only 2 cases. We encountered an industrial process operator with occupational contact dermatitis caused by isobornyl acrylate. OBJECTIVES: (i) To investigate

  16. 21 CFR 886.3600 - Intraocular lens.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraocular lens. 886.3600 Section 886.3600 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Prosthetic Devices § 886.3600 Intraocular lens. (a) Identification. An intraocular lens is a device made of materials...

  17. Gravitational lensing of quasars

    CERN Document Server

    Eigenbrod, Alexander

    2013-01-01

    The universe, in all its richness, diversity and complexity, is populated by a myriad of intriguing celestial objects. Among the most exotic of them are gravitationally lensed quasars. A quasar is an extremely bright nucleus of a galaxy, and when such an object is gravitationally lensed, multiple images of the quasar are produced – this phenomenon of cosmic mirage can provide invaluable insights on burning questions, such as the nature of dark matter and dark energy. After presenting the basics of modern cosmology, the book describes active galactic nuclei, the theory of gravitational lensing, and presents a particular numerical technique to improve the resolution of astronomical data. The book then enters the heart of the subject with the description of important applications of gravitational lensing of quasars, such as the measurement of the famous Hubble constant, the determination of the dark matter distribution in galaxies, and the observation of the mysterious inner parts of quasars with much higher r...

  18. COSMOLOGY WITH GRAVITATIONAL LENSES

    Directory of Open Access Journals (Sweden)

    Emilio E. Falco

    2009-01-01

    Full Text Available Gravitational lenses yield a very high rate of return on observational investment. Given their scarcity, their impact on our knowledge of the universe is very signi cant. In the weak- eld limit, lensing studies are based on well-established physics and thus o er a straightforward approach to pursue many currently pressing problems of astrophysics. Examples of these are the signi cance of dark matter and the density, age and size of the universe. I present recent developments in cosmological applications of gravitational lenses, regarding estimates of the Hubble constant using strong lensing of quasars. I describe our recent measurements of time delays for the images of SDSS J1004+4112, and discuss prospects for the future utilizing synoptic telescopes, planned and under construction.

  19. Gravitational Lenses of Wormholes

    CERN Document Server

    Nandi, K K; Zhang, Y Z; Nandi, Kamal Kanti; Zakharov, Alexander V.; Zhang, Yuan-Zhong

    2006-01-01

    Gravitational lensing by traversable Lorentzian wormholes is a new possibility and is analyzed in the strong field limit. Wormhole solutions are considered in the Einstein minimally coupled theory and in the brane world model. The observables in both the theories show significant differences from those in the Schwarzschild black hole lensing. It is shown that the zero mass wormholes act as photon sinks. Some special features of the considered solutions are pointed out.

  20. Retropupillary iris claw intraocular lens implantation in aphakia for dislocated intraocular lens

    Science.gov (United States)

    Faria, Mun Yueh; Ferreira, Nuno Pinto; Pinto, Joana Medeiros; Sousa, David Cordeiro; Leal, Ines; Neto, Eliana; Marques-Neves, Carlos

    2016-01-01

    Background Nowadays, dislocated intraocular lenses (IOLs) and inadequate capsular support are becoming a challenge for every ophthalmic surgeon. Explantation of dislocated IOL and iris claw IOL (ICIOL) are the techniques that have been used in our ophthalmic department. The aim of this study is to report our technique for retropupillar ICIOL. Methods This study is a retrospective case series. A total of 105 eyes with dislocated IOL from the patients at the Department of Ophthalmology in Santa Maria Hospital, a tertiary reference hospital in Lisbon, Portugal, from January 2012 until January 2016, had been analyzed. Of these 105 eyes, 66 eyes had dislocated one-piece IOL and 39 eyes had dislocated three-piece IOL. The latter underwent iris suture of the same IOL and were excluded from this study. The remaining 66 eyes with dislocated one-piece IOL underwent pars plana vitrectomy, that is, explantation of dislocated IOL through corneal incision and an implantation of retropupillary ICIOL. Operative data and postoperative outcomes included best corrected visual acuity, IOL position, intraocular pressure, pigment dispersion, clinical signs of endothelial cell loss, and anterior chamber depth. Results The mean follow-up was 23 months (range: 6–48 months). The mean preoperative best corrected visual acuity was 1.260±0.771 logMAR, and postoperative best corrected visual acuity was 0.352±0.400 logMAR units. Mean vision gain was 0.909 logMar units. The patients had the following complications: 1) retinal detachment was found in one patient, 2) corneal edema was found in three patients, 3) high intraocular pressure was observed in twelve patients, 4) subluxation of the IOL was observed in one patient, and 5) macular edema was found in three eyes. Conclusion The results demonstrate that retropupillary ICIOL is an easy and effective method for the correction of aphakia in patients not receiving capsule support. The safety of this procedure must be interpreted in the context

  1. Retropupillary iris claw intraocular lens implantation in aphakia for dislocated intraocular lens

    Directory of Open Access Journals (Sweden)

    Faria MY

    2016-08-01

    Full Text Available Mun Yueh Faria,1–3 Nuno Pinto Ferreira,1–3 Joana Medeiros Pinto,1–3 David Cordeiro Sousa,1–3 Ines Leal,1–3 Eliana Neto,1–3 Carlos Marques-Neves1–3 1Centro de Estudos da Visão, Universidade de Lisboa, 2Department of Ophthalmology, Hospital de Santa Maria, 3Faculty of Medicine, University of Lisbon, Lisbon, Portugal Background: Nowadays, dislocated intraocular lenses (IOLs and inadequate capsular support are becoming a challenge for every ophthalmic surgeon. Explantation of dislocated IOL and iris claw IOL (ICIOL are the techniques that have been used in our ophthalmic department. The aim of this study is to report our technique for retropupillar ICIOL.Methods: This study is a retrospective case series. A total of 105 eyes with dislocated IOL from the patients at the Department of Ophthalmology in Santa Maria Hospital, a tertiary reference hospital in Lisbon, Portugal, from January 2012 until January 2016, had been analyzed. Of these 105 eyes, 66 eyes had dislocated one-piece IOL and 39 eyes had dislocated three-piece IOL. The latter underwent iris suture of the same IOL and were excluded from this study. The remaining 66 eyes with dislocated one-piece IOL underwent pars plana vitrectomy, that is, explantation of dislocated IOL through corneal incision and an implantation of retropupillary ICIOL. Operative data and postoperative outcomes included best corrected visual acuity, IOL position, intraocular pressure, pigment dispersion, clinical signs of endothelial cell loss, and anterior chamber depth.Results: The mean follow-up was 23 months (range: 6–48 months. The mean preoperative best corrected visual acuity was 1.260±0.771 logMAR, and postoperative best corrected visual acuity was 0.352±0.400 logMAR units. Mean vision gain was 0.909 logMar units. The patients had the following complications: 1 retinal detachment was found in one patient, 2 corneal edema was found in three patients, 3 high intraocular pressure was observed in

  2. Sleeveless-extrusion cannula for levitation of dislocated intraocular lens.

    Science.gov (United States)

    Agarwal, Ashvin; Narang, Priya; Agarwal, Amar; Kumar, Dhivya A

    2014-07-01

    To characterise a sleeveless-extrusion cannula-based suction technique to levitate dislocated intraocular lens (IOLs) and review the surgical outcome. This retrospective, non-comparative, single surgeon, interventional, consecutive case series examined 10 patients (10 eyes) who underwent the surgical procedure from October 2011 to December 2012. Reliability, reproducibility, and intraoperative and postoperative complications of the technique were analysed. The technique involved suction levitation of a 3-piece acrylic foldable IOL in six cases, 1-piece acrylic foldable IOL in three cases and a plate haptic IOL in one case. The IOL was exchanged in four eyes whereas the same IOL was repositioned in six eyes with sulcus repositioning in two eyes and glued intrascleral fixation in four eyes. Intraoperative suction loss and a subsequent IOL dislocation were reported in 1 (10%) eye. Early preoperative complications included pigment dispersion in 1 (10%) eye, grade 2 anterior chamber cellular reaction in 2 (20%) eyes and intraoperative corneal oedema in 1 (10%) eye which resolved with medical line of management. Intermediate and late complications included macular oedema in one patient (10%) which resolved considerably with medical line of management. No incidence of postoperative vitreous or retinal haemorrhage, retinal break or retinal detachment was reported. The early results demonstrate this surgical intervention as a reliable, reproducible and an effective alternative treatment option for levitation of dislocated IOLs with a low complication rate.

  3. Personalizing Intraocular Pressure: Target Intraocular Pressure in the Setting of 24-Hour Intraocular Pressure Monitoring.

    Science.gov (United States)

    Sit, Arthur J; Pruet, Christopher M

    2016-01-01

    Determining target intraocular pressure (IOP) in glaucoma patients is multifaceted, requiring attention to many different factors such as glaucoma type, severity of disease, age, race, family history, corneal thickness and hysteresis, and initial IOP. Even with all these variables accounted for, there are still patients who have progression of the disease despite achieving target IOP. Intraocular pressure variability has been identified as a potential independent risk factor for glaucoma progression but is currently difficult to quantify in individual patients. New technologies enabling measurement of both diurnal and nocturnal IOP may necessitate modifying our concept of target pressure.

  4. Study on Titanium Nitride Film Modified for Intraocular Lens

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Objective:To study the characteristics of the intraocular lens using ion beam sputtering depositing titanium nitride thin film on the intraocular lens(IOLs).Methods:To deposite titanium nitride thin film on the top of intraocular lens by ion beam sputtering depositing.We analyzed the surface morphology of intraocular lens through SEM and AFM.We detected intraocular lens resolution through the measurement of intraocular lens.Biocompatibility of intraocular lens is preliminary evaluated in this test.Results:T...

  5. 23-gauge Transconjunctival Sutureless Vitrectomy in Eyes with Posteriorly Dislocated Intraocular Lens after Cataract Surgery

    Directory of Open Access Journals (Sweden)

    Fatih Horozo¤lu

    2011-08-01

    Full Text Available Purpose: To evaluate the outcomes of 23-gauge (23-G transconjunctival sutureless vitrectomy (TSV in eyes with posteriorly dislocated intraocular lens (IOL after cataract surgery. Material and Method: In this retrospective study, we evaluated 6 eyes of 6 consecutive cases with posteriorly dislocated intraocular lens after cataract surgery between April 2007 and November 2010. Visual acuity, intraocular pressure, detailed fundus examination and details of surgery were recorded. Results: The mean age of the patients was 64.7 years and the mean follow-up was 5.5 months (3-12 months. All eyes received 23-G TSV. Dislocated IOL was removed from the vitreous and implanted into ciliary sulcus in 2 eyes (33.3% with polymethylmetacrilate IOL and in 4 eyes (66.7% with 3-piece hydrophilic acrylic IOL. In 5 of the 6 eyes (83.7%, visual acuity improved postoperatively. In one eye (16.7%, elevation of intraocular pressure was observed postoperatively and controlled by topical treatment. Discussion: 23-G TSV surgery may be used in eyes with posteriorly IOLs after cataract surgery. Studies with a larger number of patients would better demonstrate the efficacy of this method. (Turk J Ophthalmol 2011; 41: 213-6

  6. Bonding auto-polymerising acrylic resin to acrylic denture teeth.

    LENUS (Irish Health Repository)

    Nagle, Susan

    2009-09-01

    This study investigated the effect of surface treatments on the shear bond strength of an auto-polymerising acrylic resin cured to acrylic denture teeth. The surface treatments included a combination of grit-blasting and\\/or wetting the surface with monomer. Samples were prepared and then stored in water prior to shear testing. The results indicated that the application of monomer to the surface prior to bonding did not influence the bond strength. Grit blasting was found to significantly increase the bond strength.

  7. Wearable smart sensor systems integrated on soft contact lenses for wireless ocular diagnostics

    Science.gov (United States)

    Kim, Joohee; Kim, Minji; Lee, Mi-Sun; Kim, Kukjoo; Ji, Sangyoon; Kim, Yun-Tae; Park, Jihun; Na, Kyungmin; Bae, Kwi-Hyun; Kyun Kim, Hong; Bien, Franklin; Young Lee, Chang; Park, Jang-Ung

    2017-04-01

    Wearable contact lenses which can monitor physiological parameters have attracted substantial interests due to the capability of direct detection of biomarkers contained in body fluids. However, previously reported contact lens sensors can only monitor a single analyte at a time. Furthermore, such ocular contact lenses generally obstruct the field of vision of the subject. Here, we developed a multifunctional contact lens sensor that alleviates some of these limitations since it was developed on an actual ocular contact lens. It was also designed to monitor glucose within tears, as well as intraocular pressure using the resistance and capacitance of the electronic device. Furthermore, in-vivo and in-vitro tests using a live rabbit and bovine eyeball demonstrated its reliable operation. Our developed contact lens sensor can measure the glucose level in tear fluid and intraocular pressure simultaneously but yet independently based on different electrical responses.

  8. Retropupillary Fixation of Iris-Claw Intraocular Lens for Aphakic Eyes in Children.

    Directory of Open Access Journals (Sweden)

    Martina Brandner

    Full Text Available To report outcome, complications and safety of retropupillary fixated iris-claw intraocular lenses in a pediatric population.Retrospective study.Ten consecutive pediatric patients (15 eyes underwent placement of retropupillary fixated iris-claw intraocular lenses between October 2007 and July 2013 at the Department of Ophthalmology, Medical University Graz and General Hospital Klagenfurt, Austria. Postoperative visual acuity and complications were analyzed.Median final best-corrected visual acuity improved by 0.12 logMAR from preoperative baseline. Mean postoperative spherical equivalent was -0.05 ± 1.76 D. No serious complications were observed intra- or postoperatively during the entire follow-up period of up to 40 months. One patient experienced a haptic disenclavation with IOL subluxation immediately after a car accident.Our study demonstrates that iris-claw intraocular lens implantation behind the iris is safe in children with lack of capsular support and yields excellent visual outcome with low complication rate.

  9. Polyadic devil's lenses.

    Science.gov (United States)

    Calatayud, Arnau; Monsoriu, Juan A; Mendoza-Yero, Omel; Furlan, Walter D

    2009-12-01

    Devil's lenses (DLs) were recently proposed as a new kind of kinoform lens in which the phase structure is characterized by the "devil's staircase" function. DLs are considered fractal lenses because they are constructed following the geometry of the triadic Cantor set and because they provide self-similar foci along the optical axis. Here, DLs are generalized allowing the inclusion of polyadic Cantor distributions in their design. The lacunarity of the selected polyadic fractal distribution is an additional design parameter. The results are coined polyadic DLs. Construction requirements and interrelations among the different parameters of these new fractal lenses are also presented. It is shown that the lacunarity parameter affects drastically the irradiance profile along the optical axis, appodizing higher-order foci, and these features are proved to improve the behavior of conventional DLs under polychromatic illumination.

  10. Ab-interno scleral suture loop fixation with cow-hitch knot in posterior chamber intraocular lens decentration

    OpenAIRE

    Ertugrul Can; Nurullah Koçak; Özlem Eski Yücel; Adem Gül; Hilal Eser Öztürk; Osman Sayin

    2016-01-01

    Aim of Study: To describe a simplified ab-interno cow-hitch suture fixation technique for repositioning decentered posterior chamber intraocular lens (PC IOL). Materials and Methods: Two cases are presented with the surgical correction of decentered and subluxated IOL. Ab-interno scleral suture fixation technique with hitch-cow knot in the eye was performed with a ciliary sulcus guide instrument and 1 year follow-up was completed. Results: Both of the patients had well centered lenses postope...

  11. 40 CFR 721.2805 - Acrylate ester.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Acrylate ester. 721.2805 Section 721... Acrylate ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as an acrylate ester (PMN P-96-824) is subject to reporting under...

  12. Isobornyl acrylate contact allergy: Rare or underdiagnosed?

    NARCIS (Netherlands)

    Christoffers, W.A.; Coenraads, P.J.; Schuttelaar, M.L.A.

    2012-01-01

    Background: Allergic contact dermatitis to isobornyl acrylate has been reported in only two cases in literature. Therefore, isobornyl acrylate is not part of a (meth) acrylates patch test series. At our department an industrial worker presented with therapy-resistant hand eczema and sensitizations f

  13. Gravitational Lensing & Stellar Dynamics

    CERN Document Server

    Koopmans, L V E

    2005-01-01

    Strong gravitational lensing and stellar dynamics provide two complementary and orthogonal constraints on the density profiles of galaxies. Based on spherically symmetric, scale-free, mass models, it is shown that the combination of both techniques is powerful in breaking the mass-sheet and mass-anisotropy degeneracies. Second, observational results are presented from the Lenses Structure & Dynamics (LSD) Survey and the Sloan Lens ACS (SLACS) Survey collaborations to illustrate this new methodology in constraining the dark and stellar density profiles, and mass structure, of early-type galaxies to redshifts of unity.

  14. MRI and intraocular tamponade media

    Energy Technology Data Exchange (ETDEWEB)

    Manfre, I. (Dept. of Neuroradiology, Inst. of Neurosurgery, Univ. of Catania (Italy)); Fabbri, G. (Dept. of Neuroradiology, Inst. of Neurosurgery, Univ. of Catania (Italy)); Avitabile, T. (Inst. of Ophthalmology, Univ. of Catania (Italy)); Biondi, P. (Inst. of Ophthalmology, Univ. of Catania (Italy)); Reibaldi, A. (Inst. of Ophthalmology, Univ. of Catania (Italy)); Pero, G. (Dept. of Neuroradiology, Inst. of Neurosurgery, Univ. of Catania (Italy))

    1993-05-01

    Thirteen patients who underwent surgery for retinal detachment and injection of intraocular tamponade media (silicone oil, flurosilicone oil, or perfluoro-carbon liquid) underwent magnetic resonance imaging (MRI), using spin-echo T1- and T2-weighted images. The ophthalmic tamponade media showed different signal intensity, according to their chemical structure. Unlike ophthalmoscopy or ultrasonography, MRI showed no oil-related artefact, making possible recognition of recurrent retinal detachment. (orig.)

  15. Results of Iris-Claw Intraocular Lens Implantation in Aphakia

    Directory of Open Access Journals (Sweden)

    Mehmet Tahir Şam

    2014-12-01

    Full Text Available Objectives: To evaluate the visual outcomes and complications of iris-claw intraocular lenses (ICIOL implanted in cases of aphakia or in cataract surgery with insufficient capsule support. Material and Method: In this retrospective study, we reviewed the medical records of 34 eyes of 34 patients who had undergone ICIOL implantation with a minimum follow-up of 12 months in Bucak State Hospital and in a private hospital between November 2007 and November 2012. Results: Twenty-one eyes with complicated cataract accompanied by zonular deficiency, 8 eyes with aphakia, and 5 eyes with dislocated IOL were operated and ICIOL implanted. Mean preoperative BCVA was 1.46±1.05 LogMAR and postoperative BCVA was 0.20±0.21 LogMAR. There was an improvement in visual acuity in 31 eyes of the 34 patients, and 29 of them had a visual acuity better than 6/12 postoperatively. Mean postoperative spherical equivalent (SE was -0.76±0.94 D, and deviation from estimated SE was -0.26±0.94 D. Mean preoperative astigmatism was -1.36±0.77 Cyl D and mean postoperative astigmatism was -0.98±0.82 Cyl D. In second postoperative month, one case had a pupillary block glaucoma due to the closure of peripheral iridotomy, and after ND-YAG laser treatment, intraocular pressure return to normal value. One eye had iris pigment precipitates on the ICIOL in early postoperative period, and in one case, there was a pupillary ovalization. Three months after a cataract surgery, retinal detachment developed in one eye of a patient who had a history of severe ocular trauma; anterior vitrectomy and ICIOL implantation were performed. Visual acuity remained unchanged after a successful pars plana vitrectomy operation. Conclusion: Iris-claw lenses provide fairly good visual outcomes in aphakic eyes without capsular support and in challenging cataract cases with zonular deficiency. They are safe regarding complications when compared to other alternative intraocular lens implantation methods

  16. Overlooked retained intraocular foreign body

    Directory of Open Access Journals (Sweden)

    Adžić-Zečević Antoaneta

    2015-01-01

    Full Text Available Introduction. The most common cause for litigation against ophthalmologists in a trauma case is a missed intraocular foreign body (IOFB. IOFBs cause internal eye damage, but some will come to rest in the posterior segment of the eye. Case report. We presented a 57-year-old male who was referred to the ophthalmologist due to decreased visual acuity in his left eye. Slit lamp examination of his left eye showed no pathological findings. Goldmann contact lens examination showed IOFB which was lying in the vitreous body in the inferior-temporal region. Retinal rupture was noticed at 7 o’clock. The optical coherence tomography (OCT examination was performed and it showed atrophic macular area as well as decreased peripapillar retinal fiber layers thickness. Ultrasound showed the IOFB in vitreous body cavity. History revealed that the patient had an accidental trauma, 48 years ago, when an old bomb from World War II (WWII exploded. Due to the decrease in visual acuity and fibrosis of the vitreous body surgical intervention was performed on his left eye (phacoemulsification with intraocular lens implantation, pars plana vitrectomy and instrumental extraction of foreign body. Conclusion. The intraocular foreign body (IOFB was asymptomatic for 48 years. Symptoms depend on material and localization of the foreign body and the type of injury.

  17. Gravitational lensing & stellar dynamics

    NARCIS (Netherlands)

    Koopmans, L. V. E.; Mamon, GA; Combes, F; Deffayet, C; Fort, B

    2006-01-01

    Strong gravitational lensing and stellar dynamics provide two complementary and orthogonal constraints on the density profiles of galaxies. Based on spherically symmetric, scale-free, mass models, it is shown that the combination of both techniques is powerful in breaking the mass-sheet and mass-ani

  18. Gravitational lensing & stellar dynamics

    NARCIS (Netherlands)

    Koopmans, L. V. E.; Mamon, GA; Combes, F; Deffayet, C; Fort, B

    2006-01-01

    Strong gravitational lensing and stellar dynamics provide two complementary and orthogonal constraints on the density profiles of galaxies. Based on spherically symmetric, scale-free, mass models, it is shown that the combination of both techniques is powerful in breaking the mass-sheet and

  19. Gravitational lensing & stellar dynamics

    NARCIS (Netherlands)

    Koopmans, L. V. E.; Mamon, GA; Combes, F; Deffayet, C; Fort, B

    2006-01-01

    Strong gravitational lensing and stellar dynamics provide two complementary and orthogonal constraints on the density profiles of galaxies. Based on spherically symmetric, scale-free, mass models, it is shown that the combination of both techniques is powerful in breaking the mass-sheet and mass-ani

  20. SYNTHESIS OF SOAP-FREE ACRYLIC HYDROSOLS

    Institute of Scientific and Technical Information of China (English)

    Li Jia; Zong-hui Liu; De-qing Wei

    2002-01-01

    Poly(methyl methacrylate/ethyl acrylate/acrylic acid) hydrosols were prepared by employing soap-freepolymerization, and (acrylic acid/butyl acrylate) oligomer was used as the polymeric surfactant. The effect of reactioncondition on the morphology and particle size of the hydrosols was investigated. The minimum amount of acrylic acid in thehydrosols is 2%. The maximum weight average molecular weight (Mw) of polymer that assures soap-free emulsionconversion into hydrosol is about 1.2 × 105-1.3 × 105. The particle transforming process was investigated, and an obviouschange of particle diameter and morphology was observed.

  1. Obituary--rigid contact lenses.

    Science.gov (United States)

    Efron, Nathan

    2010-10-01

    Scleral and corneal rigid lenses represented 100 per cent of the contact lens market immediately prior to the invention of soft lenses in the mid-1960s. In the United Kingdom today, rigid lenses comprise 2 per cent of all new lens fits. Low rates of rigid lens fitting are also apparent in 27 other countries which have recently been surveyed. Thus, the 1998 prediction of the author that rigid lenses--also referred to as 'rigid gas permeable' (RGP) lenses or 'gas permeable' (GP) lenses--would be obsolete by the year 2010 has essentially turned out to be correct. In this obituary, the author offers 10 reasons for the demise of rigid lens fitting: initial rigid lens discomfort; intractable rigid lens-induced corneal and lid pathology; extensive soft lens advertising; superior soft lens fitting logistics; lack of rigid lens training opportunities; redundancy of the rigid lens 'problem solver' function; improved soft toric and bifocal/varifocal lenses; limited uptake of orthokeratology; lack of investment in rigid lenses; and the emergence of aberration control soft lenses. Rigid lenses are now being fitted by a minority of practitioners with specialist skills/training. Certainly, rigid lenses can no longer be considered as a mainstream form of contact lens correction. May their dear souls (bulk properties) rest in peace.

  2. Experimentally observe the effect of spherical aberration on diffractive intraocular lens using adaptive optics

    Science.gov (United States)

    Guo, Huanqing; DeLestrange, Elie

    2015-03-01

    We first investigated the similarity in optical quality of a batch of diffractive intraocular lenses (DIOLs), providing experimental evidence for one DIOL as representative of a batch. Using adaptive optics, we then evaluated one DIOL under different levels of Zernike spherical aberration (SA) by applying both a point spread function test and a psychophysical visual acuity test. We found that for small aperture size SA has the effect of shifting the through-focus curve of DIOL. Also, for a relatively large aperture size, it has different effects on the distant and near foci.

  3. Pars plana cicatrization of sewn-in posterior chamber intraocular lens haptics.

    Science.gov (United States)

    McDermott, M L; Puklin, J E

    1997-03-01

    The authors describe the unexpected finding of cicatrization of posterior chamber lens haptics to the pars plana. This was found during removal of a secondary, transscleral sewn-in pseudophakos during a retinal reattachment procedure. Ophthalmic history and intraoperative photography revealed pars plana cicatrization of haptics. Despite removal of trans-scleral prolene fixation sutures and application of gentle traction, the posterior chamber lens haptics remained firmly adherent to pars plana retina. The haptics were amputated to prevent significant chorioretinal damage. The conventional belief that all sewn-in posterior chamber intraocular lenses cause little or no scarring response around the haptics may be unfounded.

  4. Learning unit: Thin lenses

    Science.gov (United States)

    Nita, L.-S.

    2012-04-01

    Learning unit: Thin lenses "Why objects seen through lenses are sometimes upright and sometimes reversed" Nita Laura Simona National College of Arts and Crafts "Constantin Brancusi", Craiova, Romania 1. GEOMETRIC OPTICS. 13 hours Introduction (models, axioms, principles, conventions) 1. Thin lenses (Types of lenses. Defining elements. Path of light rays through lenses. Image formation. Required physical quantities. Lens formulas). 2. Lens systems (Non-collated lenses. Focalless systems). 3. Human eye (Functioning as an optical system. Sight defects and their corrections). 4. Optical instruments (Characteristics exemplified by a magnifying glass. Paths of light rays through a simplified photo camera. Path of light rays through a classical microscope) (Physics curriculum for the IXth grade/ 2011). This scenario exposes a learning unit based on experimental sequences (defining specific competencies), as a succession of lessons started by noticing a problem whose solution assumes the setup of an experiment under laboratory conditions. Progressive learning of theme objectives are realised with sequential experimental steps. The central cognitive process is the induction or the generalization (development of new knowledge based on observation of examples or counterexamples of the concept to be learnt). Pupil interest in theme objectives is triggered by problem-situations, for example: "In order to better see small objects I need a magnifying glass. But when using a magnifier, small object images are sometimes seen upright and sometimes seen reversed!" Along the way, pupils' reasoning will converge to the idea: "The image of an object through a lens depends on the relative distances among object, lens, and observer". Associated learning model: EXPERIMENT Specific competencies: derived from the experiment model, in agreement with the following learning unit steps I. Evoking - Anticipation: Size of the problem, formulation of hypotheses and planning of experiment. II

  5. Glaucoma therapy by extended release of timolol from nanoparticle loaded silicone-hydrogel contact lenses.

    Science.gov (United States)

    Jung, Hyun Jung; Abou-Jaoude, Michelle; Carbia, Blanca E; Plummer, Caryn; Chauhan, Anuj

    2013-01-10

    Glaucoma is the second major cause of blindness in the world after cataract. Glaucoma management through eye drops that reduce the intraocular pressure (IOP) has major deficiencies including low patient compliance and low bioavailability. Extended wear contact lenses that deliver glaucoma drugs for extended periods could increase patient compliance, while also increasing the bioavailability. To develop extended wear contact lenses that can also provide extended glaucoma therapy, we disperse nanoparticles of PGT (propoxylated glyceryl triacylate) that contain a glaucoma drug timolol. The particles can also be loaded into prefabricated lenses by soaking the lenses in a solution of particles in ethanol. The particle loaded gels can release timolol in phosphate buffered saline (PBS) for about a month at room temperature. The most likely rate controlling mechanism is hydrolysis of the ester bond that links timolol to the PGT matrix, but other mechanisms such as water and drug diffusion, drug dissolution, drug-polymer chain cleavage, time-dependent drug permeability within the polymeric matrix, etc. may also be important. Nanoparticle incorporation in the silicone hydrogels results in reduction in ion and oxygen permeabilities, and an increase in modulus, and the impact on each of these properties is proportional to the particle loading. A gel with 5% particle loading can deliver timolol at therapeutic doses for about a month at room temperature, with a minimal impact on critical lens properties. Preliminary animal studies in Beagle dogs conducted with lenses in which particles are loaded by soaking the lenses in ethanol show a reduction in IOP.

  6. Pulsar lensing geometry

    CERN Document Server

    Liu, Siqi; Macquart, J-P; Brisken, Walter; Deller, Adam

    2015-01-01

    Our analysis of archival VLBI data of PSR 0834+06 revealed that its scintillation properties can be precisely modelled using the inclined sheet model (Pen & Levin 2014), resulting in two distinct lens planes. These data strongly favour the grazing sheet model over turbulence as the primary source of pulsar scattering. This model can reproduce the parameters of the observed diffractive scintillation with an accuracy at the percent level. Comparison with new VLBI proper motion results in a direct measure of the ionized ISM screen transverse velocity. The results are consistent with ISM velocities local to the PSR 0834+06 sight-line (through the Galaxy). The simple 1D structure of the lenses opens up the possibility of using interstellar lenses as precision probes for pulsar lens mapping, precision transverse motions in the ISM, and new opportunities for removing scattering to improve pulsar timing. We describe the parameters and observables of this double screen system. While relative screen distances can i...

  7. Intraocular lens with accommodation capacity

    OpenAIRE

    Dorronsoro, Carlos; Alejandre, Nicolás; Bekesi, Nandor; Marcos, Susana

    2014-01-01

    Intraocular lens with accommodation capacity comprising a first optical member (1) having a dynamic optical power, to which a second optical member (2) with a fixed optical power is affixed, in such a manner that at least a central part of each of one of one of the curved surfaces (2a, 2b) of the second optical member (2) and of at least one of the surfaces (1a, 1b) of the first optical member (1) are in contact with each other, the second optical member (2) and the first optical member (1) p...

  8. Additional multifocal sulcus-based intraocular lens: alternative to multifocal intraocular lens in the capsular bag.

    Science.gov (United States)

    Schrecker, Jens; Kroeber, Sandra; Eppig, Timo; Langenbucher, Achim

    2013-04-01

    To compare the visual outcomes of additional multifocal intraocular lenses (IOLs) for sulcus fixation with those of standard multifocal IOLs in the capsular bag. Department of Ophthalmology, Rudolf-Virchow-Klinikum Glauchau, Glauchau, Germany. Prospective controlled clinical trial. Eyes had phacoemulsification and implantation of a monofocal IOL in the capsular bag and an additional aberration-free diffractive IOL in the ciliary sulcus (multifocal add-on IOL group). Measurements of uncorrected and distance-corrected distance, intermediate, and near visual acuities; contrast sensitivity; and defocus curve were performed 3 months postoperatively. Results were compared with those in eyes with an aberration-correcting diffractive posterior chamber IOL (multifocal PC IOL group). The multifocal add-on IOL group comprised 34 eyes of 20 patients and the multifocal PC IOL group, 31 eyes of 17 patients. Cataract surgery, IOL implantation, and the postoperative course were uneventful in all cases. There were no statistically significant differences in uncorrected and distance-corrected distance, intermediate, or near visual acuities between the 2 groups. The median uncorrected distance visual acuity was 0.00 logMAR in both groups, and the median uncorrected near visual acuity was 0.10 logMAR in both groups. Contrast sensitivity testing yielded significantly better results in the multifocal add-on IOL group, especially at spatial frequencies over 1.5 cycles per degree. Defocus curves were similar in the 2 groups. Visual performance with a multifocal diffractive add-on IOL was equivalent to that achieved with a commonly used multifocal diffractive PC IOL. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  9. Biocompatibility of intraocular lens materials%人工晶体材料的生物相容性特征★

    Institute of Scientific and Technical Information of China (English)

    王洋; 韩宏光

    2013-01-01

      BACKGROUND: The visual recovery and complications of the cataract patients are various after different intraocular lens materials implantation, so the selection of appropriate intraocular lens materials is the key of the research. OBJECTIVE: To investigate the properties and biocompatibility of intraocular lens materials. METHODS: The materials were classified according to the hardness and location of the intraocular lens after implantation in order to analyze the pros and cons of the intraocular lens thus guiding the patients to select the appropriate intraocular lens for implantation. The properties and biocompatibility of the commonly used intraocular lens materials were evaluated. RESUTLS AND CONCLUSION: Polymethylmethacrylate intraocular lens is the first choice of rigid material, but it cannot tolerate autoclaving. Acrylic intraocular lens is the soft and foldable intraocular lens that has the similar optical and biological properties with polymethylmethacrylate intraocular lens, and it can improve the visual acuity after implantation with less complications. Posterior capsular opacification is the most important indicator for biocompatibility evaluation which is related with the material and design of intraocular lens. The stability of intraocular lens in the capsular bag is also the indicator to evaluate the biocompatibility. The material properties, biocompatibility, and visual function should be taking into consideration in the design and selection of intraocular lens materials. Guarantee the efficacy after intraocular lens implantation and reduce the incidence of complications, so that to get vision rehabilitation for the cataract patients.%  背景:白内障患者植入不同材料人工晶体治疗后的视力恢复情况和并发症有所不同,选择适宜的人工晶体材料是研究的关键。目的:探讨人工晶体材料的特征和生物相容性。方法:按人工晶体的硬度和植入后不同位置将材料进行分类

  10. Vinyl Acetate/butyl acrylate/acrylate Research of Ternary Soap-free Emulsion Polymerization

    Directory of Open Access Journals (Sweden)

    Xiao Li-guang

    2016-01-01

    Full Text Available Through the vinyl acetate/butyl acrylate/acrylic acrylic emulsion preparation without soap vinegar, with solid content, gel, emulsion stability and film forming properties and tensile strength as the main index to study the effect of raw materials on the properties of emulsion. Through the infrared spectrometer soap-free emulsion for microscopic analysis research. Study of the ternary soap-free vinegar acrylic emulsion with good performance.

  11. Real and Pseudoaccommodation in Accommodative Lenses

    Directory of Open Access Journals (Sweden)

    Ioannis G. Pallikaris

    2011-01-01

    Full Text Available In the attempt to manage presbyopia, different intraocular lens designs have been proposed such as monofocal IOLs with monovision or multifocal IOLs. Even though the lenses mentioned offer satisfactory visual results, contemporary ophthalmology has not completely answered the presbyopic dilemma by simulating the accommodative properties of the crystalline lens itself. Accommodative IOLs were designed to fill this gap and provide satisfactory vision for all distances by restoring some degree of “pseudoaccommodation.” Pseudo accommodative capability can be linked to monofocal IOL’s as well but the results are not satisfactory enough to fully support unaided near vision. Pseudoaccommodation is a complex phenomenon that can be attributed to several static (i.e., pupil size, against-the-rule cylindrical refractive error, multifocality of the cornea and dynamic (i.e., anterior movement of the implant itself factors. Objective measurement of the accommodative capability offered by the accommodative IOLs is extremely difficult to obtain, and different methods such as autorefractometers, retinoscopy, and ultrasound imaging during accommodative effort, ray tracing, or pharmacological stimulation have been developed but the results are sometimes inconsistent. Despite the difficulties in measuring accommodation, accommodative IOLs represent the future in the attempt to successfully “cure” presbyopia.

  12. Toric intraocular lens orientation and residual refractive astigmatism: an analysis

    Directory of Open Access Journals (Sweden)

    Potvin R

    2016-09-01

    Full Text Available Rick Potvin,1 Brent A Kramer,2 David R Hardten,3 John P Berdahl4 1Science in Vision, Akron, NY, 2University of Iowa Carver College of Medicine, Iowa City, IA, 3Minnesota Eye Consultants, Minnetonka, MN, 4Vance Thompson Vision, Sioux Falls, SD, USA Purpose: To analyze intraocular lens (IOL orientation data from an online toric back-calculator (astigmatismfix.com for determining if differences were apparent by lens type.Methods: A retrospective review of astigmatismfix.com toric back-calculations that included IOL identification and intended orientation axis.Results: Of 12,812 total validated calculation records, 8,229 included intended orientation and lens identification data. Of the latter, 5,674 calculations (69% involved lenses oriented 5° or more from their intended position. Using estimated toric lens usage data, the percentage of lenses with orientation ≥5° from intended was 0.89% overall, but the percentage varied significantly between specific toric lens brands (P<0.05. The percentage of back-calculations related to lenses that were not oriented as intended was also statistically significantly different by lens brand (P<0.05. When IOLs were misoriented, they were significantly more likely to be misoriented in a counterclockwise direction (P<0.05. This was found to be due to a bias toward counterclockwise orientation observed with one specific brand, a bias that was not observed with the other three brands analyzed here.Conclusion: The percentage of eyes with lens orientation ≥5° from intended in the Toric Results Analyzer data set was <1% of toric IOLs in general, with the relative percentage of Tecnis® Toric IOLs significantly higher than AcrySof® Toric IOLs. Both of these had higher rates than the Staar® Toric and Trulign® Toric lenses, with the availability of higher Tecnis and AcrySof cylinder powers a likely contributing factor. The AcrySof Toric IOL appears to be less likely than the Tecnis Toric IOL to cause residual

  13. Additive manufacturing of tunable lenses

    Science.gov (United States)

    Schlichting, Katja; Novak, Tobias; Heinrich, Andreas

    2017-02-01

    Individual additive manufacturing of optical systems based on 3D Printing offers varied possibilities in design and usage. In addition to the additive manufacturing procedure, the usage of tunable lenses allows further advantages for intelligent optical systems. Our goal is to bring the advantages of additive manufacturing together with the huge potential of tunable lenses. We produced tunable lenses as a bundle without any further processing steps, like polishing. The lenses were designed and directly printed with a 3D Printer as a package. The design contains the membrane as an optical part as well as the mechanical parts of the lens, like the attachments for the sleeves which contain the oil. The dynamic optical lenses were filled with an oil. The focal length of the lenses changes due to a change of the radius of curvature. This change is caused by changing the pressure in the inside of the lens. In addition to that, we designed lenses with special structures to obtain different areas with an individual optical power. We want to discuss the huge potential of this technology for several applications. Further, an appropriate controlling system is needed. Wéll show the possibilities to control and regulate the optical power of the lenses. The lenses could be used for illumination tasks, and in the future, for individual measurement tasks. The main advantage is the individuality and the possibility to create an individual design which completely fulfills the requirements for any specific application.

  14. Cross-correlating Planck CMB lensing with SDSS: Lensing-lensing and galaxy-lensing cross-correlations

    CERN Document Server

    Singh, Sukhdeep; Brownstein, Joel R

    2016-01-01

    We present first results from cross-correlating Planck CMB lensing maps with the Sloan Digital Sky Survey (SDSS) galaxy lensing shape catalog and BOSS galaxy catalogs. For galaxy position vs. CMB lensing cross-correlations, we measure the convergence signal around the galaxies in configuration space, using the BOSS LOWZ ($z\\sim0.30$) and CMASS ($z\\sim0.57$) samples. With fixed Planck 2015 cosmology, doing a joint fit with the galaxy clustering measurement, for the LOWZ (CMASS) sample we find a galaxy bias $b_g=1.75\\pm0.04$ ($1.95\\pm 0.02$) and galaxy-matter cross-correlation coefficient $r_{cc}=1.0\\pm0.2$ ($0.8\\pm 0.1$) using $20lensing. Using the same scales and including the galaxy-galaxy lensing measurements, we constrain $\\Omega_m=0.284\\pm0.024$ and relative calibration bias between the CMB lensing and galaxy lensing to be $b_\\gamma=0.82^{+0.15}_{-0.14}$. The combination of galaxy lensing and CMB lensing also allows us to measure the cosmolo...

  15. Design of a Test Bench for Intraocular Lens Optical Characterization

    Science.gov (United States)

    Alba-Bueno, Francisco; Vega, Fidel; Millán, María S.

    2011-01-01

    The crystalline lens is the responsible for focusing at different distances (accommodation) in the human eye. This organ grows throughout life increasing in size and rigidity. Moreover, due this growth it loses transparency through life, and becomes gradually opacified causing what is known as cataracts. Cataract is the most common cause of visual loss in the world. At present, this visual loss is recoverable by surgery in which the opacified lens is destroyed (phacoemulsification) and replaced by the implantation of an intraocular lens (IOL). If the IOL implanted is mono-focal the patient loses its natural capacity of accommodation, and as a consequence they would depend on an external optic correction to focus at different distances. In order to avoid this dependency, multifocal IOLs designs have been developed. The multi-focality can be achieved by using either, a refractive surface with different radii of curvature (refractive IOLs) or incorporating a diffractive surface (diffractive IOLs). To analyze the optical quality of IOLs it is necessary to test them in an optical bench that agrees with the ISO119679-2 1999 standard (Ophthalmic implants. Intraocular lenses. Part 2. Optical Properties and Test Methods). In addition to analyze the IOLs according to the ISO standard, we have designed an optical bench that allows us to simulate the conditions of a real human eye. To do that, we will use artificial corneas with different amounts of optical aberrations and several illumination sources with different spectral distributions. Moreover, the design of the test bench includes the possibility of testing the IOLs under off-axis conditions as well as in the presence of decentration and/or tilt. Finally, the optical imaging quality of the IOLs is assessed by using common metrics like the Modulation Transfer Function (MTF), the Point Spread Function (PSF) and/or the Strehl ratio (SR), or via registration of the IOL's wavefront with a Hartmann-Shack sensor and its

  16. Design of a Test Bench for Intraocular Lens Optical Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Alba-Bueno, Francisco; Vega, Fidel; Millan, Maria S, E-mail: francisco.alba-bueno@upc.edu, E-mail: fvega@oo.upc.edu, E-mail: millan@oo.upc.edu [Departamento de Optica y Optometria, Universidad Politecnica de Cataluna, C/ Violinista Vellsola 37, 08222 Terrassa (Spain)

    2011-01-01

    The crystalline lens is the responsible for focusing at different distances (accommodation) in the human eye. This organ grows throughout life increasing in size and rigidity. Moreover, due this growth it loses transparency through life, and becomes gradually opacified causing what is known as cataracts. Cataract is the most common cause of visual loss in the world. At present, this visual loss is recoverable by surgery in which the opacified lens is destroyed (phacoemulsification) and replaced by the implantation of an intraocular lens (IOL). If the IOL implanted is mono-focal the patient loses its natural capacity of accommodation, and as a consequence they would depend on an external optic correction to focus at different distances. In order to avoid this dependency, multifocal IOLs designs have been developed. The multi-focality can be achieved by using either, a refractive surface with different radii of curvature (refractive IOLs) or incorporating a diffractive surface (diffractive IOLs). To analyze the optical quality of IOLs it is necessary to test them in an optical bench that agrees with the ISO119679-2 1999 standard (Ophthalmic implants. Intraocular lenses. Part 2. Optical Properties and Test Methods). In addition to analyze the IOLs according to the ISO standard, we have designed an optical bench that allows us to simulate the conditions of a real human eye. To do that, we will use artificial corneas with different amounts of optical aberrations and several illumination sources with different spectral distributions. Moreover, the design of the test bench includes the possibility of testing the IOLs under off-axis conditions as well as in the presence of decentration and/or tilt. Finally, the optical imaging quality of the IOLs is assessed by using common metrics like the Modulation Transfer Function (MTF), the Point Spread Function (PSF) and/or the Strehl ratio (SR), or via registration of the IOL's wavefront with a Hartmann-Shack sensor and its

  17. Roulettes: A weak lensing formalism for strong lensing - I. Overview

    CERN Document Server

    Clarkson, Chris

    2016-01-01

    We present a new perspective on gravitational lensing. We describe a new extension of the weak lensing formalism capable of describing strongly lensed images. By integrating the non-linear geodesic deviation equation, the amplification matrix of weak lensing is generalised to a sum over independent amplification tensors of increasing rank. We show how an image distorted by a generic lens may be constructed as a sum over `roulettes', which are the natural curves associated with the independent spin modes of the amplification tensors. Highly distorted images can be constructed even for large sources observed near or within the Einstein radius of a lens where the shear and convergence are large. The amplitude of each roulette is formed from a sum over appropriate derivatives of the lensing potential. Consequently, measuring these individual roulettes for images around a lens gives a new way to reconstruct a strong lens mass distribution without requiring a lens model. This formalism generalises the convergence, ...

  18. RHIC electron lenses upgrades

    Energy Technology Data Exchange (ETDEWEB)

    Gu, X. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Altinbas, Z. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Binello, S. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Costanzo, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drees, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Gassner, D. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hock, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Harvey, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Michnoff, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Miller, T. A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Pikin, A. I. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Shrey, T. C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Tan, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Than, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; White, S. M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2015-05-03

    In the Relativistic Heavy Ion Collider (RHIC) 100 GeV polarized proton run in 2015, two electron lenses were used to partially compensate for the head-on beam-beam effect for the first time. Here, we describe the design of the current electron lens, detailing the hardware modifications made after the 2014 commissioning run with heavy ions. A new electron gun with 15-mm diameter cathode is characterized. The electron beam transverse profile was measured using a YAG screen and fitted with a Gaussian distribution. During operation, the overlap of the electron and proton beams was achieved using the electron backscattering detector in conjunction with an automated orbit control program.

  19. Clinical study of customized aspherical intraocular lens implants

    Institute of Scientific and Technical Information of China (English)

    Lie-Xi; Jia; Zhao-Hui; Li

    2014-01-01

    AIM:To compare if there is an improvement in visual functions with age-related cataracts between patients receiving a aspherical intraocular lens(IOL) based on corneal wavefront aberration and patients randomly assigned lenses.METHODS:A total of 124 eyes of 124 patients with age-related cataracts were placed in experimental group and a group receiving randomly assigned(RA) lenses.The experimental group was undergone Pentacam corneal spherical aberration measurement before surgery; the targeted range for residual total spherical aberration after surgery was set to 0-0.3 μm. Patients with a corneal spherical aberration <0.3 μm were implanted with a zero-spherical aberration advanced optics(AO) aspherical IOL and patients with an aberration ≥0.3 μm received a Tecnis Z9003 aspherical lens in experimental group. RA patients were randomly implanted with an AO lens or a Tecnis Z9003 lens. Three months after surgery total spherical aberration, photopic/mesopic contrast sensitivities, photopic/mesopic with glare contrast sensitivities, and logMAR vision were measured.RESULTS:Statistical analysis on logMAR vision showed no significant difference between two groups(P =0.413). The post-surgical total spherical aberration was 0.126 ±0.097 μm and 0.152 ±0.151 μm in the experimental and RA groups, respectively(P =0.12). The mesopic contrast sensitivities at spatial frequencies of 6,12 and 18 c/d in the experimental group were significantly higher than of the RA group(P =0.00; P =0.04;P =0.02). The mesopic with glare contrast sensitivity in the experimental group at a spatial frequency of 18 c/d was also significantly higher vs the RA group(P =0.01).CONCLUSION:Pre-surgical corneal spherical aberration measurement in cataract patients followed bycustomized selection of aspherical IOL implants improved mesopic contrast sensitivities at high spatial frequencies, and thus is a superior strategy compared to the random selection of aspherical intraocular lens implants.

  20. Piggyback implantation using Toric intraocular lens in high myopia

    Directory of Open Access Journals (Sweden)

    Qiong-Yan Tang

    2014-09-01

    Full Text Available AIM: To assess the postoperative outcomes of piggyback implantation using Acrysof Toric intraocular lens(IOLin high myopia combined with corneal astigmatism. METHODS: Sixty patients who had phacoemulsification with IOL implantation due to high myopia,cataract and corneal astigmatism from January 2010 to June 2013 were randomly divided into observation group(piggyback Toric IOL implantation, both an Acrysoft IQ Toric IOL and a minus foldable acrylic three piece IOL were implanted in the capsular bag, n=30and control group(foldable IOL implantation, n=30. Postoperative follow-up went on 6mo. Information collected included uncorrected visual acuity(UCVA, IOL position, residual astigmatism and complications. RESULTS: The UCVA increased from 3.52±0.03 preoperatively to 4.78±0.01 at 6mo postoperatively in the observation group, from 3.51±0.03 preoperatively to 4.30±0.13 at 6mo postoperatively in the control group. The observation group's postoperative UCVA was better than that of the control group. There was statistically significant difference(t=3.612, Pt=-11.995, PCONCLUSION: Piggyback implantation using Toric IOL can help to solve the problem of no matching Toric IOL power for the high myopia combined with corneal astigmatism at the current stage. It improves the UCVA and reduces the astigmatism after the cataract surgery.

  1. INTRAOCULAR LENS POSITION IN COMBINED PHACOEMULSIFICATION AND VITREORETINAL SURGERY.

    Science.gov (United States)

    Ozates, Serdar; Kiziltoprak, Hasan; Koc, Mustafa; Uzel, Mehmet Murat; Teke, Mehmet Yasin

    2017-10-09

    To assess the decentration and angle of tilt of the intraocular lens (IOL) according to the intravitreal tamponade types used in combined phacoemulsification and vitreoretinal surgery. This prospective and randomized clinical study involved 73 eyes of 69 patients who underwent combined vitreoretinal surgery. Eyes with intravitreal tamponades formed the study group and eyes without intravitreal tamponades formed the control group. The study group was further divided into silicone oil and gas tamponade subgroups. Cross-sectional IOL images were captured using a Pentacam HR (Oculus, Germany) and tilt and decentration were calculated with Adobe Photoshop software (Adobe, San Jose, CA). The mean angle of tilt and decentration at the vertical meridian were significantly higher in both tamponade groups than in the control group (P 0.05). When comparing the silicone oil and gas tamponade subgroups, no significant differences were noted on the position of IOL at both meridians (P > 0.05 for all). Intravitreal tamponades have an important effect on the position of IOL in combined vitreoretinal surgery. Silicone oil and gas tamponades may induce postoperative tilt and decentration of one-piece acrylic IOLs.

  2. Reverse Optic Capture to Stabilize a Toric Intraocular Lens

    Directory of Open Access Journals (Sweden)

    Howard V. Gimbel

    2013-09-01

    Full Text Available Purpose: To describe a technique for stabilizing a rotationally unstable toric intraocular lens (IOL. Method: Case report and literature review. Results: Surgical technique and long-term follow-up for a patient who underwent repositioning and stabilization of a mobile 1-piece acrylic toric IOL using reverse optic capture (ROC are described. This patient presented with early, more than 70° off-axis rotation. The IOL was repositioned but was very mobile within the bag and tended to rotate off-axis; hence, it was stabilized in the desired position by capturing the optic through the anterior continuous curvilinear capsulorhexis, leaving the haptics in the bag. The immediate and 2-year postoperative follow-up revealed a stable and on-axis IOL with no visual, refractive or ocular complications. Conclusions: ROC is a useful and safe technique to address the problem of toric IOLs that tend to rotate at the time of surgery or are not stable postoperatively.

  3. [Free-Floating Intraocular Cysts].

    Science.gov (United States)

    Werner, Jens Ulrich; Lang, Gerhard K; Enders, Christian

    2017-05-03

    Background Free-floating intraocular cysts may be found in the anterior chamber (FZV) and the vitreous (FZG). The first description of a cyst was 150 years ago, and they are considered to be ocular rarities. Materials and Methods The actual knowledge about FZV and FZG is shown on the basis of two exemplary patients. Results and Discussion Patient 1 had a FZV as an incidental finding which had a smooth surface, a slight pigmentation and was translucent. The ultrasound biomicroscopy revealed an echo-free interior space. Without the patient's discomfort and missing treatment indication, a watch-and-wait strategy was chosen. Cysts of the iris can be classified as primary and secondary cysts. Primary cysts of the iris can arise from the stroma as the pigment epithelium wherein it is believed that FZV descend from the pigment epithelium. Secondary cysts and FZV can be generated by tumors, inflammation, epithelial ingrowth, the use of eye-drops or intraocular foreign bodies. Patient 2 showed marked myopic fundus changes and an FZG with a yellowish-greenish surface; the transparency was reduced and the surface was not pigmented. The ultrasound examination also revealed an echo-free interior space. Clinical controls were advised. Congenital and acquired causes are discussed for the formation of FZG. FZG could originate from the pigment epithelium of the iris, but there are conflicting study results. Trauma, inflammation and chorioretinal diseases are considered as a reason for acquired causes of FZG. The genesis, especially of FZG, is still unclear. For the treatment of patients with FZV and FZG, it is important to know the potential causes to be able to make a therapeutic decision. High quality photographic and sonographic documentation is needed in the watch-and-wait strategy. Georg Thieme Verlag KG Stuttgart · New York.

  4. Hydrophilic acrylic intraocular lens opacification after descemet stripping automated endothelial keratoplasty

    Directory of Open Access Journals (Sweden)

    Amir Norouzpour

    2016-01-01

    Conclusion: In an eye with UZS and iatrogenic aniridia, IOL opacification may result from direct contact between the IOL surface and exogenous air. Aniridia can be a risk factor for development of IOL opacification after DSAEK. Further studies are required to confirm this hypothesis.

  5. Halo-lensing or Self-lensing? Locating the MACHO Lenses

    Science.gov (United States)

    Nelson, C. A.; Cook, K. H.; Popowski, P.; Drake, A. J.; Marshall, S. L.; Griest, K.; Vandehei, T.; Alcock, C.; Allsman, R. A.; Axelrod, T. S.; Freeman, K. C.; Peterson, B. A.; Alves, D. R.; Becker, A. C.; Stubbs, C. W.; Tomaney, A. B.; Bennett, D. P.; Geha, M.; Lehner, M. J.; Minniti, D.; Pratt, M. R.; Quinn, P. J.; Sutherland, W.; Welch, D.; MACHO Collaboration

    2000-12-01

    There are two principle geometrical arrangements which may explain Large Magellanic Cloud (LMC) microlensing: a) halo-lensing, in which the lensed object is part of the Milky Way galactic halo and b) self-lensing, in which the lensed object is part of the LMC. Self-lensing in turn may be broken into two categories: LMC-LMC self-lensing, in which both the source and the lens reside in the LMC and background self-lensing, in which the lens is a star in the LMC and the source star is drawn from some population behind the LMC. Models suggest the contribution of LMC-LMC self-lensing is small, so the nature of LMC microlensing may be estimated from the location of the microlensing source stars. If the source stars are in the LMC then microlensing is dominated by halo-lensing; conversely if the source stars are located behind the LMC then microlensing is dominated by self-lensing. Since background populations reside behind the LMC, we expect them to be both redder and fainter then the average population of the LMC. We attempt to determine if the MACHO source stars come from such a background population by comparing the HST color-magnitude diagram (CMD) of source stars to the CMD of the average population of the LMC and looking for the effects of extra reddening and extinction. The microlensing source stars are identified by deriving accurate centroids in the ground-based MACHO images using difference image analysis (DIA) and then transforming the DIA coordinates to the HST frame. Preliminary results suggest that halo-lensing accounts for ≳ 40% of the observed microlensing results. Support provided by NASA, DOE, NSF and NPSC.

  6. Magnetic electron lenses

    CERN Document Server

    1982-01-01

    No single volume has been entirely devoted to the properties of magnetic lenses, so far as I am aware, although of course all the numerous textbooks on electron optics devote space to them. The absence of such a volume, bringing together in­ formation about the theory and practical design of these lenses, is surprising, for their introduction some fifty years ago has created an entirely new family of commercial instruments, ranging from the now traditional transmission electron microscope, through the reflection and transmission scanning microscopes, to co­ lumns for micromachining and microlithography, not to mention the host of experi­ mental devices not available commercially. It therefore seemed useful to prepare an account of the various aspects of mag­ netic lens studies. These divide naturally into the five chapters of this book: the theoretical background, in which the optical behaviour is described and formu­ lae given for the various aberration coefficients; numerical methods for calculat­ ing...

  7. Intraocular pressure estimation using proper orthogonal decomposition

    CSIR Research Space (South Africa)

    Botha, N

    2012-07-01

    Full Text Available Glaucoma is the second leading cause of irreversible blindness. The primary indicator for glaucoma is an elevated intraocular pressure, which is estimated by means of contact or non-contact tonometry. However, these techniques do not accurately...

  8. Evaluation of visual acuity under different contrasts and luminances in eyes implanted with aspheric multifocal intraocular lenses%非球面多焦点人工晶状体植入眼不同背景亮度及不同对比度视功能观察

    Institute of Scientific and Technical Information of China (English)

    赵银莹; 李军花; 常平骏; 赵云娥

    2010-01-01

    目的 分析非球面多焦点人工晶状体(MIOL)[ReSTOR MIOL(SN6AD3)]植入眼在不同背景亮度不同对比度下的视功能.方法 采用前瞻性研究.2009年2月至2009年7月行白内障超声乳化吸除并植入SN6AD3且随访资料完整的病例26例(42眼),术后6个月在最佳远矫正状态下,采用多功能电子视力测量仪(MFVA-100)测试不同背景亮度(250、85、25 cd/m2)下不同对比度(100%、25%、10%、5%)视标的LogMAR视力.采用Dunnett's T3多重比较法对所得视力进行统计分析.结果 在250 cd/m2背景亮度下,不同对比度(100%、25%、10%、5%)视力平均值分别为0.01、0.23、0.40、0.62;85 cd/m2背景亮度下为0.02、0.26、0.46、0.74;25 cd/m2背景亮度下为0.08、0.32、0.49、0.63;在这3种背景亮度下,视力随着对比度下降而下降,差异有统计学意义(P均<0.05).同一对比度视标,不同背景亮度(250、85、25 cd/m2)下的视力采用Dunnett's T3多重比较法分析,结果示差异无统计学意义(P均>0.05).结论 植入非球面ReSTOR MIOL(SN6AD3)患者无论在高亮(250 cd/m2)、标准(85 cd/m2)、中间(25 cd/m2)背景亮度下均可获得满意的视力.视标的对比度对视力的影响较背景亮度更大.%Objective To evaluate the differences in contrast visual acuity (VA) under different background illuminations in patients who had been implanted with the ReSTOR aspheric multifocal intraocular lens (MIOL)(SN6AD3). Methods This was a prospective study. Forty-two eyes of 26 patients who had received ReSTOR MIOL (SN6AD3) implantation after cataract extraction were enrolled. Six months postoperatively, best corrected distance VA was measured at 4 contrast levels (100%, 25%, 10%, 5%) under 3 background illumination levels (250 cd/m2, 85 cd/m2, 25 cd/m2)using a multi-functional visual acuity tester (MFVA-100). Dunnett's T3 multiple comparison was used for statistical anaylysis. Results The mean VA at the 4 contrast levels (100%, 25%, 10%, 5%)under 250 cd

  9. Roulettes: a weak lensing formalism for strong lensing: I. Overview

    Science.gov (United States)

    Clarkson, Chris

    2016-08-01

    We present a new perspective on gravitational lensing. We describe a new extension of the weak lensing formalism capable of describing strongly lensed images. By integrating the nonlinear geodesic deviation equation, the amplification matrix of weak lensing is generalised to a sum over independent amplification tensors of increasing rank. We show how an image distorted by a generic lens may be constructed as a sum over ‘roulettes’, which are the natural curves associated with the independent spin modes of the amplification tensors. Highly distorted images can be constructed even for large sources observed near or within the Einstein radius of a lens where the shear and convergence are large. The amplitude of each roulette is formed from a sum over appropriate derivatives of the lensing potential. Consequently, measuring these individual roulettes for images around a lens gives a new way to reconstruct a strong lens mass distribution without requiring a lens model. This formalism generalises the convergence, shear and flexion of weak lensing to arbitrary order, and provides a unified bridge between the strong and weak lensing regimes. This overview paper is accompanied by a much more detailed paper II, arXiv:1603.04652.

  10. Refraction changes during elevation of intraocular pressure by suction cup, their reflection in the pattern visual evoked cortical potential and their compensation.

    Science.gov (United States)

    Bernd, A; Ulrich, W D; Teubel, H; Rohrwacher, F; Barth, T

    1993-01-01

    Visual evoked cortical potential studies using pattern stimuli with the intraocular pressure raised artificially by the suction cup method have been reported. Possible changes in the refraction of the eye due to the method employed and their influence on the pattern visual evoked cortical potential have not been considered. Changes in the refraction of the eye during artificial intraocular pressure elevation and the influence of such changes on pattern visual evoked cortical potentials were studied. The refraction changes were found to depend on the shape of the suction cup. They could be compensated for by employing properly shaped suction cups and contact lenses. The behavior of amplitude and latency of the pattern visual evoked cortical potential at artificially elevated intraocular pressure with compensation for refraction changes has been studied and found to depend in a characteristic manner on ocular perfusion pressure.

  11. Subaru Weak Lensing Measurements of Four Strong Lensing Clusters: Are Lensing Clusters Over-Concentrated?

    Energy Technology Data Exchange (ETDEWEB)

    Oguri, Masamune; Hennawi, Joseph F.; Gladders, Michael D.; Dahle, Haakon; Natarajan, Priyamvada; Dalal, Neal; Koester, Benjamin P.; Sharon, Keren; Bayliss, Matthew

    2009-01-29

    We derive radial mass profiles of four strong lensing selected clusters which show prominent giant arcs (Abell 1703, SDSS J1446+3032, SDSS J1531+3414, and SDSS J2111-0115), by combining detailed strong lens modeling with weak lensing shear measured from deep Subaru Suprime-cam images. Weak lensing signals are detected at high significance for all four clusters, whose redshifts range from z = 0.28 to 0.64. We demonstrate that adding strong lensing information with known arc redshifts significantly improves constraints on the mass density profile, compared to those obtained from weak lensing alone. While the mass profiles are well fitted by the universal form predicted in N-body simulations of the {Lambda}-dominated cold dark matter model, all four clusters appear to be slightly more centrally concentrated (the concentration parameters c{sub vir} {approx} 8) than theoretical predictions, even after accounting for the bias toward higher concentrations inherent in lensing selected samples. Our results are consistent with previous studies which similarly detected a concentration excess, and increases the total number of clusters studied with the combined strong and weak lensing technique to ten. Combining our sample with previous work, we find that clusters with larger Einstein radii are more anomalously concentrated. We also present a detailed model of the lensing cluster Abell 1703 with constraints from multiple image families, and find the dark matter inner density profile to be cuspy with the slope consistent with -1, in agreement with expectations.

  12. LENSED: a code for the forward reconstruction of lenses and sources from strong lensing observations

    Science.gov (United States)

    Tessore, Nicolas; Bellagamba, Fabio; Metcalf, R. Benton

    2016-12-01

    Robust modelling of strong lensing systems is fundamental to exploit the information they contain about the distribution of matter in galaxies and clusters. In this work, we present LENSED, a new code which performs forward parametric modelling of strong lenses. LENSED takes advantage of a massively parallel ray-tracing kernel to perform the necessary calculations on a modern graphics processing unit (GPU). This makes the precise rendering of the background lensed sources much faster, and allows the simultaneous optimization of tens of parameters for the selected model. With a single run, the code is able to obtain the full posterior probability distribution for the lens light, the mass distribution and the background source at the same time. LENSED is first tested on mock images which reproduce realistic space-based observations of lensing systems. In this way, we show that it is able to recover unbiased estimates of the lens parameters, even when the sources do not follow exactly the assumed model. Then, we apply it to a subsample of the Sloan Lens ACS Survey lenses, in order to demonstrate its use on real data. The results generally agree with the literature, and highlight the flexibility and robustness of the algorithm.

  13. Primary Posterior Chamber Intraocular Lens Implantation in Traumatic Cataract With Posterior Capsule Breaks

    Institute of Scientific and Technical Information of China (English)

    YupingZou; WenhuiYang

    1995-01-01

    Background:In patients with incomplete posterior capsule support,posterior chamber intraocular lenses(PC-IOLs)were implanted with both haptics transs-cleral fixation.This causes more damage to the eye and may result in more com-plications,In patients with small posterior breaks,non-fixation or single haptic fixation may be adequate.Methods:Thiry-two consecutive patients of traumatic cataract with posterior capsule breaks caused by penetrating eye trauma were retospected.Posterior chamber intraocular lenses were implanted in all these patients with three tech-niques,ie,without fixation,with single haptic fixation and with both haptics fixation .The selection of the technique was based on the position and size of the posterior capsule.The follow-up period was 21days to 28months(mean,15.2months).Results:Intra-operative problems included ciliary body bleeding(Two patents,6.25%)and enlargement of posterior capsule breaks(2patients,6.25).Postoperative visual acuity was0.5or better(Corrected)in28case(87.5%)and 0.1-0.4in four patients(12.5%),Postoperative complications included hyphema(6eyes,18.8%),transient intraocular pressure elevation(6eyes,18.8%),transient hypotention(7eyes,21.8%).Postoperative IOL position were good except one case of IOL tilt.No pupillary capture or endophthalmitis was found.Conclusions:Not all PC-IOLs have to be fixed by two haptics.In patients with small posterior capsule breaks,PC-IOLmay not be fixed or fixed by only one haptics.Eye Science1995;11:140-142.

  14. Intraocular cilia associated with perforating injury

    Directory of Open Access Journals (Sweden)

    Gopal Lingam

    2000-01-01

    Full Text Available Purpose: To report a case series of penetrating injury complicated by occurrence of intraocular cilia. Methods: Retrospective analysis of charts of 11 eyes of 11 patients with penetrating injury and intraocular cilia, presenting between September 1978 and November 1998. Ten eyes underwent surgery for trauma-related problems such as cataract, vitritis, retinal detachment etc., at which time intraocular cilia were removed. One eye did not have surgery and continues to harbour cilia at the posterior perforation site. Results: Metallic wire was responsible for injury in 6 of 11 eyes with intraocular cilia. Five eyes had significant intraocular inflammation. The cilia were located in the anterior segment in 4 eyes; in the posterior segment in 6 eyes and in both in one eye. At the last follow up, 72.7% had 6/18 or better vision. Poor vision in the rest was due to recurrent retinal detachment (2 eyes and macular scarring (1 eye. Conclusion: Intraocular cilia are more commonly associated with injury by a metallic wire. The presentation and management of an injured eye does not seem to be influenced by the presence of cilia in the eye.

  15. Clinical observation on visual quality in patients implanted with monofocal and multifocal aspheric intraocular lenses%多焦点与单焦点非球面人工晶状体植入后视觉质量的临床观察

    Institute of Scientific and Technical Information of China (English)

    王文莹; 王军; 张晶; 赵世强; 马剑欣

    2010-01-01

    眼近视力较好,阅读脱镜率较高,具有较好的视觉功能,但对比敏感度有所下降.%Objective To evaluate the visual quality in patients implanted with aspheric diffractive multifocal intraocular lens. Methods Prospective nonrandomized controlled study. One hundred cataract eyes in 50 patients were included. Patients received AcrySof IQ ReSTOR IOL (SN6AD3) or AcrySof IQ IOL (SN60WF) implantation. The follow up period was 6 months. The mean of unconnected distance visual acuity ( UCDVA) , best corrected distance visual acuity ( BCDVA), unconnected near visual acuity (UCNVA), best distance-corrected near visual acuity (BCNVA) and intermediate unconrrected visual acuity in patients with SN6AD3 and SN60WF was compared preoperatively and postoperatively in all patients. Photopic and mesopic contrast sensitivity function with and without glare were tested at 6 months after operation. Aberrations were recorded postoperatively. Subjective outcomes were assessed by VF-14 questionnaire. The chi-square test was applied to compare categorical variables and the paired-samples t test was used to compare the measure data. Results Postoperatively, there were no significant differences between groups in spherical equivalent (SE) (t=0.233, P = 0.876), UCDVA (t = 1.018, P=0.265) or BCNVA (t = 0. 679, P = 0. 501). The BCDVA in the monofocal IOL group was better than that in the multifocal IOL group (t = 2. 388, P = 0. 021). UCNVA improved remarkably after the implantation of multifocal IOL (t = 11. 311 ,P =0.000). The intermediate UCVA in the monofocal IOL eyes was butter than that in the multifocal IOL at 60 cm(t =2.414,P=0.020). The total aberration (F = 5. 169,P =0. 041), total low grade (F =4.973,P =0.036) and total high grade total aberrations (F =4.640,P = 0.048) were higher in the multifocal IOL group. There was no difference between these two groups in the defocus ( F = 0.862, P=0.358), astigmatism(F=3.893, P=0.052), spherical aberration(F = 1.743, P=0

  16. Meta-analysis of clinical randomized controlled trials comparing refractive with diffractive multifocal intraocular lenses in cataract surgery%折射型与衍射型多焦点人工晶状体临床应用效果随机临床对照试验的Meta分析

    Institute of Scientific and Technical Information of China (English)

    邵德望; 何守志

    2014-01-01

    及中距视力;衍射型MIOL表现出更好的裸眼近视力,出现光晕、眩光等视觉不良反应的可能性更小;在戴镜矫正状况下,衍射型MIOL与折射型MIOL的远、中、近视力表现相同.%Objective To systematic review the effectiveness of refractive multifocal intraocular lens (MIOL) versus diffractive MIOL in the treatment of cataract.Method Randomized controlled trials comparing refractive MIOL with diffractive MIOL were identified by searching PubMed (1966 to May,2013),EMbase (1980 to May,2013),Medline (1966 to May,2013),and The Cochrane Library (Issue 1,2013).We also hand-searched related journals.All the searches were restricted in English or Chinese.Methodological quality of randomized controlled trials (RCT) was evaluated by simple evaluate method that recommended by the Cochrane Collaboration.Data extracted by two reviewers with designed extraction form.RevMan software (release 5.2) was used for data management and analysis.Results A total of 11 trials (1460 eyes) were included for systematic review.Subgroup analyses were used according to different model comparison of MIOL.The results showed a significant difference in the mean of the uncorrected distance visual acuity (UCDVA) and the uncorrected intermediate visual acuity (UCIVA) in the refractive MIOLgroup with WMD-0.04,95% CI-0.06 to-0.03 (P <0.01) and WMD-0.05,95% CI-0.09 to-0.02 (P =0.001).It showed a significantly difference in the mean of the uncorrected near visual acuity (UCNVA),complete spectacle independent rate,halo rate and glare rate in the diffractive MIOL group with WMD 0.11,95% CI 0.08 to0.15 (P<0.01),WMD2.98,95%CI2.17 to4.09 (P<0.01),WMD 1.52,95% CI 1.14 to 2.04 (P =0.004) and WMD 1.27,95% CI 1.07 to 1.50 (P =0.005).There was no significant difference between the two groups in the mean of the best corrected distance visual acuity (BCDVA),the best distance corrected intermediate visual acuity (BDCIVA),the best distance corrected near visual

  17. Lenses for JWST

    Science.gov (United States)

    Ebeling, Harald; Richard, Johan; Kneib, Jean-Paul; Repp, Andrew; Atek, Hakim; Egami, Eiichi; Windhorst, Rogier; Edge, Alastair

    2016-08-01

    JWST will dramatically advance our knowledge and understanding of the first generations of galaxies at z>10, their role in the re-ionization of the Universe, and the evolutionary processes that gave rise to the complexity and diversity of galaxies at the current epoch. As demonstrated by HST legacy projects like CLASH and the Hubble Frontier Fields, gravitational amplification by massive galaxy clusters can significantly extend the depth of the required observations. However, for JWST, reducing any diffuse background light will be just as crucial. We here propose Spitzer/IRAC observations of six massive cluster lenses, specifically selected as candidates for observation with JWST. By (a) quantifying the amount of intra-cluster light and (b) enabling us to improve our current lens models, the data resulting from the requested observations will be instrumental for the final selection of cluster targets that maximize the scientific returns of deep JWST observations.

  18. Lensed Quasar Hosts

    CERN Document Server

    Peng, C Y; Rix, H W; Keeton, C R; Falco, E E; Kochanek, C S; Lehár, J; McLeod, B A; Peng, Chien Y.; Impey, Chris D.; Rix, Hans-Walter; Keeton, Charles R.; Falco, Emilio E.; Kochanek, Chris S.; Lehar, Joseph; Leod, Brian A. Mc

    2006-01-01

    Gravitational lensing assists in the detection of quasar hosts by amplifying and distorting the host light away from the unresolved quasar core images. We present the results of HST observations of 30 quasar hosts at redshifts 1 1.7 is a factor of 3--6 higher than the local value. But, depending on the stellar content the ratio may decline at z>4 (if E/S0-like), flatten off to 6--10 times the local value (if Sbc-like), or continue to rise (if Im-like). We infer that galaxy bulge masses must have grown by a factor of 3--6 over the redshift range 3>z>1, and then changed little since z~1. This suggests that the peak epoch of galaxy formation for massive galaxies is above z~1. We also estimate the duty cycle of luminous AGNs at z>1 to be ~1%, or 10^7 yrs, with sizable scatter.

  19. Comparison between OPD-scan results and contrast sensitivity of three intraocular lenses: spheric AcrySof SN60AT, aspheric AcrySof SN60WF and multifocal AcrySof Restor lens Estudo comparativo da análise de frente de onda e sensibilidade ao contraste entre as lentes intra-oculares multifocal AcrySof Restor SN60D3, monofocal AcrySof SN60WF asférica e a monofocal SN60AT esférica

    Directory of Open Access Journals (Sweden)

    Celso Takashi Nakano

    2009-08-01

    ção com implantes de lentes intraoculares AcrySof SN60D3 multifocal, AcrySof SN60WF monofocal asférica e AcrySof SA60AT monofocal esférica. Métodos: Trinta e dois olhos com a lente intraocular multifocal, 32 olhos com a lente intraocular monofocal asférica e 32 olhos com a lente intraocular monofocal esférica. A avaliação oftalmológica foi realizada no primeiro, terceiro, sétimo, e nonagésimo dia pós-operatório. Todos os exames foram padronizados, realizada por um único examinador sob condições controladas de luminosidade fotópicas estabelecidas em 85 cd/m², medida por meio de tabelas de ETDRS, sensibilidade ao contraste e análise de aberrometria com OPD-Scan. Resultados: As médias de aberração total foi superior no grupo SN60AT (KW = 9.42; p=0.009 quando comparada com o grupo SN60D3 (p=0.016 e o grupo SN60WF (p=0.0047. O grupo SN60AT (KW = 16.20; p=0.0003 apresentou superioridade nas medias de aberração esférica comparada com o grupo SN60WF (p=0.00046 e o grupo SN60D3 (p=0.0014. Nenhuma diferença significante foi encontrada na acuidade visual para longe com e sem correção óptica com a tabela de ETDRS a 100% e 9% de contraste. O grupo SN60D3 comparada a SN60AT (p=0.016 apresentou baixa sensibilidade ao contraste em condições fotópicas com diferença estatística a 6.0 cpg (KW = 7.84; p=0.0199, mas sem diferença estatística entre os grupos SN60WF e SN60AT (p=0.91 e entre os grupos SN60WF e SN60D3 (p=0.051. O grupo SN60D3 apresentou baixa sensibilidade ao contraste em condições mesópicas (KW = 10.79; p=0,0045 a 6cpg quando comparada com o grupos SN60AT (p=0.011 e SN60WF (p=0.007. Conclusão: As lentes intraoculares multifocais e asféricas apresentaram menos aberração esférica quando comparadas à lente intraocular esférica, além da prevista multifocalidade sem correção para longe e perto. Entretanto, o grupo multifocal apresentou baixa sensibilidade ao contraste.

  20. Cross-correlating Planck CMB lensing with SDSS: lensing-lensing and galaxy-lensing cross-correlations

    Science.gov (United States)

    Singh, Sukhdeep; Mandelbaum, Rachel; Brownstein, Joel R.

    2017-01-01

    We present results from cross-correlating Planck cosmic microwave background (CMB) lensing maps with the Sloan Digital Sky Survey (SDSS) galaxy lensing shape catalogue and BOSS (Baryon Oscillation Spectroscopic Survey) galaxy catalogues. For galaxy position versus CMB lensing cross-correlations, we measure the convergence signal around the galaxies in configuration space, using the BOSS LOWZ (z ˜ 0.30) and CMASS (z ˜ 0.57) samples. With fixed Planck 2015 cosmology, doing a joint fit with the galaxy clustering measurement, for the LOWZ (CMASS) sample we find a galaxy bias bg = 1.75 ± 0.04 (1.95 ± 0.02) and galaxy-matter cross-correlation coefficient rcc = 1.0 ± 0.2 (0.8 ± 0.1) using 20 < rp < 70 h-1 Mpc, consistent with results from galaxy-galaxy lensing. Using the same scales and including the galaxy-galaxy lensing measurements, we constrain Ωm = 0.284 ± 0.024 and relative calibration bias between the CMB lensing and galaxy lensing to be b_γ =0.82^{+0.15}_{-0.14}. The combination of galaxy lensing and CMB lensing also allows us to measure the cosmological distance ratios (with zl ˜ 0.3, zs ˜ 0.5) R=D_s D_{l,*}/D_{* D_{l,s}}=2.68± 0.29, consistent with predictions from the Planck 2015 cosmology (R=2.35). We detect the galaxy position-CMB convergence cross-correlation at small scales, rp < 1 h-1 Mpc, and find consistency with lensing by NFW haloes of mass Mh ˜ 1013 h-1 M⊙. Finally, we measure the CMB lensing-galaxy shear cross-correlation, finding an amplitude of A = 0.76 ± 0.23 (zeff = 0.35, θ < 2°) with respect to Planck 2015 Λ cold dark matter predictions (1σ level consistency). We do not find evidence for relative systematics between the CMB and SDSS galaxy lensing.

  1. Intraocular Pressure After 2 Hours of Small-Diameter Scleral Lens Wear.

    Science.gov (United States)

    Nau, Cherie B; Schornack, Muriel M; McLaren, Jay W; Sit, Arthur J

    2016-11-01

    Compression of episcleral veins or deformation of tissue in the Schlemm's canal beneath the landing zone of scleral lenses could elevate intraocular pressure (IOP). We examined the effect of 2 hr of small-diameter scleral lens wear on IOP. Twenty-nine participants, 29 ± 6 years old (mean ± SD) who experienced no history of eye disease or scleral lens wear, were included in the study. Each participant was fitted with a 15-mm Jupiter scleral lens on one eye (study eye). Intraocular pressure was measured in both eyes by pneumatonometry centrally on the cornea and peripherally on the sclera. The lens was then placed on one eye and was worn for 2 hr. Intraocular pressure was remeasured immediately after lens placement, at 1 and 2 hr of lens wear, and immediately after lens removal. Intraocular pressure after removal of the scleral lens was compared with IOP before placing the lens and to IOP in the control eye using paired t tests. Immediately after removing the scleral lens, mean central IOP in the study eye (13.9 ± 3.1 mm Hg) was not different from mean central IOP in the control eye (13.5 ± 2.2 mm Hg, P = 0.4) or in the same eye before lens wear (13.6 ± 1.9 mm Hg, P = 0.6). There were also no differences in IOP measured peripherally at 2 hr of lens wear (P = 0.8). Neophyte scleral lens wear of a 15-mm scleral lens for 2 hr does not increase IOP in healthy eyes.

  2. 21 CFR 573.120 - Acrylamide-acrylic acid resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Acrylamide-acrylic acid resin. 573.120 Section 573... Food Additive Listing § 573.120 Acrylamide-acrylic acid resin. Acrylamide-acrylic acid resin... acrylamide with partial hydrolysis, or by copolymerization of acrylamide and acrylic acid with the greater...

  3. Monolithic F-16 Uniform Thickness Stretched Acrylic Canopy Transparency Program

    Science.gov (United States)

    1984-01-01

    Thermoforming Finite Strain Analysis Finite Element Modeling Mooney Formulation Tensile Testing Acrylic Material Properties F-16 Transparency Thinning Uniform...OF ACRYLIC TENSILE SPECIMEN ...... 8 MARC ANALYSIS OF ACRYLIC HEMISPHERE ............ 12 IV ACRYLIC MATERIAL PROPERTIES AT THERMOFORMING TEMPERATURES...properties (necessary for finite element stress analysis work) were generated at temperatures in the range of thermoforming . A finite element code

  4. Lensed: a code for the forward reconstruction of lenses and sources from strong lensing observations

    CERN Document Server

    Tessore, Nicolas; Metcalf, R Benton

    2015-01-01

    Robust modelling of strong lensing systems is fundamental to exploit the information they contain about the distribution of matter in galaxies and clusters. In this work, we present Lensed, a new code which performs forward parametric modelling of strong lenses. Lensed takes advantage of a massively parallel ray-tracing kernel to perform the necessary calculations on a modern graphics processing unit (GPU). This makes the precise rendering of the background lensed sources much faster, and allows the simultaneous optimisation of tens of parameters for the selected model. With a single run, the code is able to obtain the full posterior probability distribution for the lens light, the mass distribution and the background source at the same time. Lensed is first tested on mock images which reproduce realistic space-based observations of lensing systems. In this way, we show that it is able to recover unbiased estimates of the lens parameters, even when the sources do not follow exactly the assumed model. Then, we...

  5. Biopsy techniques for intraocular tumors

    Directory of Open Access Journals (Sweden)

    Pukhraj Rishi

    2016-01-01

    Full Text Available Biopsy involves the surgical removal of a tissue specimen for histopathologic evaluation. Most intraocular tumors are reliably diagnosed based on the clinical evaluation or with noninvasive diagnostic techniques. However, accurately diagnosing a small percentage of tumors can be challenging. A tissue biopsy is thus needed to establish a definitive diagnosis and plan the requisite treatment. From fine-needle aspiration biopsy (FNAB to surgical excision, all tissue collection techniques have been studied in the literature. Each technique has its indications and limitations. FNAB has been reported to provide for 88-95% reliable and safe ophthalmic tumor diagnosis and has gained popularity for prognostic purposes and providing eye conserving treatment surgeries. The technique and instrumentation for biopsy vary depending upon the tissue involved (retina, choroid, subretinal space, vitreous, and aqueous, suspected diagnosis, size, location, associated retinal detachment, and clarity of the media. The cytopathologist confers a very important role in diagnosis and their assistance plays a key role in managing and planning the treatment for malignancies.

  6. The genetics of intraocular pressure.

    Science.gov (United States)

    Ojha, Pallavi; Wiggs, Janey L; Pasquale, Louis R

    2013-01-01

    Glaucoma is a leading cause of irreversible blindness. Intraocular pressure (IOP) is the only modifiable risk factor for glaucoma, yet there is little known about the molecular events that regulate IOP. Genetic and genomic studies have helped identify genes that influence IOP and could lead to the identification of biological pathways that serve as targets for novel pressure-modifying therapies. Genetic linkage studies resulted in the identification of several genes that cause Mendelian (autosomal dominant or autosomal recessive) forms of high-pressure glaucoma, including MYOC. PITX2, FOXC1, and CYP1B1. Classical twin studies suggest that IOP is a heritable trait. More recently, genome-wide association studies (GWAS) have shown that common genetic variants in the GAS7 and TMCO1 genomic regions are associated with elevated IOP. TMCO1 has also been associated with primary open-angle glaucoma in patients with advanced disease. A further study identifying additional genes contributing to IOP will be necessary to fully define the underlying genetic architecture of IOP.

  7. Biopsy techniques for intraocular tumors

    Science.gov (United States)

    Rishi, Pukhraj; Dhami, Abhinav; Biswas, Jyotirmay

    2016-01-01

    Biopsy involves the surgical removal of a tissue specimen for histopathologic evaluation. Most intraocular tumors are reliably diagnosed based on the clinical evaluation or with noninvasive diagnostic techniques. However, accurately diagnosing a small percentage of tumors can be challenging. A tissue biopsy is thus needed to establish a definitive diagnosis and plan the requisite treatment. From fine-needle aspiration biopsy (FNAB) to surgical excision, all tissue collection techniques have been studied in the literature. Each technique has its indications and limitations. FNAB has been reported to provide for 88–95% reliable and safe ophthalmic tumor diagnosis and has gained popularity for prognostic purposes and providing eye conserving treatment surgeries. The technique and instrumentation for biopsy vary depending upon the tissue involved (retina, choroid, subretinal space, vitreous, and aqueous), suspected diagnosis, size, location, associated retinal detachment, and clarity of the media. The cytopathologist confers a very important role in diagnosis and their assistance plays a key role in managing and planning the treatment for malignancies. PMID:27488148

  8. Poly(meth)acrylate-based coatings.

    Science.gov (United States)

    Nollenberger, Kathrin; Albers, Jessica

    2013-12-05

    Poly(meth)acrylate coatings for pharmaceutical applications were introduced in 1955 with the launch of EUDRAGIT(®) L and EUDRAGIT(®) S, two types of anionic polymers. Since then, by introducing various monomers into their polymer chains and thus altering their properties, diverse forms with specific characteristics have become available. Today, poly(meth)acrylates function in different parts of the gastrointestinal tract and/or release the drug in a time-controlled manner. This article reviews the properties of various poly(meth)acrylates and discusses formulation issues as well as application possibilities.

  9. Occupational respiratory disease caused by acrylates.

    Science.gov (United States)

    Savonius, B; Keskinen, H; Tuppurainen, M; Kanerva, L

    1993-05-01

    Acrylates are compounds used in a variety of industrial fields and their use is increasing. They have many features which make them superior to formerly used chemicals, regarding both their industrial use and their possible health effects. Contact sensitization is, however, one of their well known adverse health effects but they may also cause respiratory symptoms. We report on 18 cases of respiratory disease, mainly asthma, caused by different acrylates, 10 cases caused by cyanoacrylates, four by methacrylates and two cases by other acrylates.

  10. Planar Lenses at Visible Wavelengths

    CERN Document Server

    Khorasaninejad, Mohammadreza; Devlin, Robert C; Oh, Jaewon; Zhu, Alexander Y; Capasso, Federico

    2016-01-01

    Sub-wavelength resolution imaging requires high numerical aperture (NA) lenses, which are bulky and expensive. Metasurfaces allow the miniaturization of conventional refractive optics into planar structures. We show that high-aspect-ratio titanium dioxide metasurfaces can be fabricated and designed as meta-lenses with NA = 0.8. Diffraction-limited focusing is demonstrated at wavelengths of 405 nm, 532 nm, and 660 nm with corresponding efficiencies of 86%, 73%, and 66%. The meta-lenses can resolve nanoscale features separated by sub-wavelength distances and provide magnification as high as 170x with image qualities comparable to a state-of-the-art commercial objective. Our results firmly establish that meta-lenses can have widespread applications in laser-based microscopy, imaging, and spectroscopy.

  11. The Thirring-Lense Effect

    Science.gov (United States)

    Embacher, Franz

    The Thirring-Lense effect is the phenomenon that an observer near a rotating mass, being in a state which is non-rotating with respect to the rest of the universe, experiences extra inertial forces, i.e. becomes dizzy. The first anticipation of the effect goes back to Ernst Mach; its first quantitative prediction on the basis of general relativity was given by Hans Thirring and Joseph Lense. Almost ninety years later, the effect seems to be experimentally verified.

  12. Anterior chamber lenses. Part II: A laboratory study.

    Science.gov (United States)

    Apple, D J; Hansen, S O; Richards, S C; Ellis, G W; Kavka-Van Norman, D; Tetz, M R; Pfeffer, B R; Park, R B; Crandall, A S; Olson, R J

    1987-03-01

    An analysis of 606 surgically removed anterior chamber intraocular lens (IOL) specimens revealed that 351 or 58% of these were small-diameter, round loop, closed-loop styles. Because of the extremely high percentage of IOLs with this design received in our laboratory and the correlation of clinical histories with our histopathologic findings, we have concluded that such IOLs do not provide the safety and efficacy achieved by other anterior chamber lens designs. The finely polished, one-piece, all-PMMA styles fared well in our study. Although these one-piece styles comprise well over 50% of the American market share of anterior chamber IOLs, they comprise only 14% of all anterior chamber IOLs accessioned in our laboratory, compared to 58% for closed-loop designs. We believe that implantation of anterior chamber lenses with small-diameter, round, closed loops is no longer warranted. Patients in whom these IOLs have already been implanted should be carefully followed. It is our opinion that the FDA should recall or closely monitor all IOLs of this design and that implantation of closed-loop lenses should be discontinued in the United States. Furthermore, we believe that an IOL deemed to be not medically sound or worthy of implantation in the United States should not be marketed or donated outside of this country.

  13. Morphological Findings of Intraocular Lens with Haptics Detached from Optics Following Cataract Surgery.

    Science.gov (United States)

    Suzuki, Yukihiko; Suzuki, Kaori; Metok, Tomomi; Nakazawai, Mitsuru

    2010-03-09

    A 55-year-old woman was treated using phacoemulsification, aspiration, and intraocular lens (IOL) implantation. Three months after surgery, the optical zone of the anterior capsule was completely closed due to strong capsular contractions. As the two haptics were found to be completely detached from the optics, the IOL was subsequently extracted and morphologically examined. Although the optics and haptics of the IOL when viewed with a stereomicroscope appeared to have no marked damage on their surfaces, an ultra-structural examination showed that a portion of the acrylic optics on the detached surface was defective. We considered that the IOL haptics might have become detached from the optics due to continuous force from postoperative capsular contractions.

  14. Short Term Effect of Exercise on Intraocular Pressure of Ocular ...

    African Journals Online (AJOL)

    Short Term Effect of Exercise on Intraocular Pressure of Ocular Hypertensive Subjects. ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search ... Keywords: Intraocular pressure; short term exercise; ocular hypertension.

  15. Refractive Results: Safety and Efficacy of Secondary Piggyback Sensar™ AR40 Intraocular Lens Implantation to Correct Pseudophakic Refractive Error

    Science.gov (United States)

    Hassan, Alahmady Hamad Alsmman; Sayed, Khulood M.; ElAgooz, Mohammed; Elhawary, Ashraf Mostafa

    2016-01-01

    In this study we evaluate the visual outcomes, safety, efficacy, and stability of implanting of second sulcus intraocular lens (IOL) to correct unsatisfied ametropic patients after phacoemulsification. Methods. Retrospective study of 15 eyes (15 patients) underwent secondary intraocular lens implanted into the ciliary sulcus. The IOL used was a Sensar IOL three-piece foldable hydrophobic acrylic IOL. The first IOL in all patients was acrylic intrabagal IOL implanted in uncomplicated phacoemulsification surgery. Results. Fifteen eyes (15 patients) were involved in this study. Preoperatively, mean log⁡MAR UDVA and CDVA were 0.88 ± 0.22 and 0.19 ± 0.13, respectively, with a mean follow-up of 28 months (range: 24 to 36 months). At the end of the follow-up, all eyes achieved log⁡MAR UDVA of 0.20 ± 0.12 with postoperative refraction ranging from 0.00 to −0.50 D of attempted emmetropia. Conclusions. Implantation of the second sulcus SensarAR40 IOL was found to be safe, easy, and simple technique for management of ametropia following uncomplicated phacoemulsification. PMID:27313869

  16. Refractive Results: Safety and Efficacy of Secondary Piggyback Sensar™ AR40 Intraocular Lens Implantation to Correct Pseudophakic Refractive Error

    Directory of Open Access Journals (Sweden)

    Alahmady Hamad Alsmman Hassan

    2016-01-01

    Full Text Available In this study we evaluate the visual outcomes, safety, efficacy, and stability of implanting of second sulcus intraocular lens (IOL to correct unsatisfied ametropic patients after phacoemulsification. Methods. Retrospective study of 15 eyes (15 patients underwent secondary intraocular lens implanted into the ciliary sulcus. The IOL used was a Sensar IOL three-piece foldable hydrophobic acrylic IOL. The first IOL in all patients was acrylic intrabagal IOL implanted in uncomplicated phacoemulsification surgery. Results. Fifteen eyes (15 patients were involved in this study. Preoperatively, mean log⁡MAR UDVA and CDVA were 0.88 ± 0.22 and 0.19 ± 0.13, respectively, with a mean follow-up of 28 months (range: 24 to 36 months. At the end of the follow-up, all eyes achieved log⁡MAR UDVA of 0.20 ± 0.12 with postoperative refraction ranging from 0.00 to −0.50 D of attempted emmetropia. Conclusions. Implantation of the second sulcus SensarAR40 IOL was found to be safe, easy, and simple technique for management of ametropia following uncomplicated phacoemulsification.

  17. Lente intra-ocular opaca em diplopia intratável: relato de caso Opaque intraocular lens in intractable diplopia: case report

    Directory of Open Access Journals (Sweden)

    Fernanda Teixeira Krieger

    2006-08-01

    Full Text Available Diplopia intratável tem sido descrita em várias situações. Métodos convencionais como prismas e correção cirúrgica do estrabismo falham em neutralizá-la. O objetivo do trabalho é documentar o caso de uma paciente com estrabismo de longa data, cuja diplopia deteriorou-se ao longo dos anos, e não foi possível resolução com cirurgia, prisma, e oclusão com óculos e lente de contato com pupila opaca. A paciente foi então submetida à facoemulsificação com implante de lente intra-ocular opaca que atingiu o objetivo desejado.Intractable diplopia has been described in many situations but poor results are the rule with standard treatment modalities. The authors report a case of a woman with long-standing strabismus and diplopia who failed to improve following surgery, prism, and occlusive spectacles or contact lenses. Then, she was submitted to phacoemulsification and opaque intraocular lens implantation, which successfully neutralized diplopia.

  18. Gel time of calcium acrylate grouting material

    Institute of Scientific and Technical Information of China (English)

    韩同春

    2004-01-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerizationreaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reactionkinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time ofcalcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and anexample is provided to verify the proposed formula.

  19. Gel time of calcium acrylate grouting material

    Institute of Scientific and Technical Information of China (English)

    韩同春

    2004-01-01

    Calcium acrylate is a polymerized grout, and can polymerize in an aqueous solution. The polymerization reaction utilizes ammonium persulfate as a catalyst and sodium thiosulfate as the activator. Based on the theory of reaction kinetics, this study on the relation between gel time and concentration of activator and catalyst showed that gel time of calcium acrylate is inversely proportional to activator and catalyst concentration. A formula of gel time is proposed, and an example is provided to verify the proposed formula.

  20. Rapid Output Growth of Special Acrylic Esters

    Institute of Scientific and Technical Information of China (English)

    Wang Lianzhi

    2007-01-01

    @@ Acrylic esters are usually classified into general-purpose varieties and special varieties. The production and application of general-purpose varieties is already quite matured in the world and their output growth tends to be flat. Owing to the development of coatings, electronics, automobiles,textiles, printing and construction sectors, especially the application of radiation curing technology in various sectors, special acrylic esters have developed rapidly.

  1. Phakic Pattern Pseudoexfoliation Material Accumulation on Intraocular Lens Surface

    Directory of Open Access Journals (Sweden)

    Emre Güler

    2014-03-01

    Full Text Available Pseudophakic pseudoexfoliation is the accumulation of pseudoexfoliation material on the intraocular lens. Most of the cases have showed scattered flecks of pseudoexfoliation material on the surface of the intraocular lens. However, the phakic pattern consisting of classic three-zone on the intraocular lens is rarely observed. In this case report, we describe a phakic pattern pseudoexfoliation material on the intraocular lens surface 8 years after cataract extraction. (Turk J Ophthalmol 2014; 44: 156-7

  2. Phakic Pattern Pseudoexfoliation Material Accumulation on Intraocular Lens Surface

    OpenAIRE

    Emre Güler; Aylin Tenlik; Tuba Kara Akyüz

    2014-01-01

    Pseudophakic pseudoexfoliation is the accumulation of pseudoexfoliation material on the intraocular lens. Most of the cases have showed scattered flecks of pseudoexfoliation material on the surface of the intraocular lens. However, the phakic pattern consisting of classic three-zone on the intraocular lens is rarely observed. In this case report, we describe a phakic pattern pseudoexfoliation material on the intraocular lens surface 8 years after cataract extraction. (Turk J Ophthalm...

  3. Triple procedure in posterior segment intraocular foreign body

    Directory of Open Access Journals (Sweden)

    Azad Rajvardhan

    1998-01-01

    Full Text Available Three patients with intraocular foreign bodies and traumatic cataracts underwent single stage pars plana lensectomy with anterior capsule preservation, vitrectomy, removal of the foreign body, and intraocular lens implantation. The preserved anterior capsule permitted support for the placement of an intraocular lens in the posterior chamber in the ciliary sulcus. The procedure enabled early visual rehabilitation. This procedure seems useful in the management of posterior segment intraocular foreign body associated with cataract.

  4. Ab-interno scleral suture loop fixation with cow-hitch knot in posterior chamber intraocular lens decentration

    Science.gov (United States)

    Can, Ertuğrul; Koçak, Nurullah; Yücel, Özlem Eşki; Gül, Adem; Öztürk, Hilal Eser; Sayın, Osman

    2016-01-01

    Aim of Study: To describe a simplified ab-interno cow-hitch suture fixation technique for repositioning decentered posterior chamber intraocular lens (PC IOL). Materials and Methods: Two cases are presented with the surgical correction of decentered and subluxated IOL. Ab-interno scleral suture fixation technique with hitch-cow knot in the eye was performed with a ciliary sulcus guide instrument and 1 year follow-up was completed. Results: Both of the patients had well centered lenses postoperatively. Corrected distant and near visual acuities of the patients were improved. There was no significant postoperative complication. In the follow-up period of 1 year, no evidence of suture erosion was found. Conclusions: Ab-interno scleral suture loop fixation with hitch-cow knot in the eye was effective in repositioning decentered or subluxated PC IOLs with excellent postoperative centered lenses and visual outcomes. PMID:27050346

  5. Ab-interno scleral suture loop fixation with cow-hitch knot in posterior chamber intraocular lens decentration

    Directory of Open Access Journals (Sweden)

    Ertugrul Can

    2016-01-01

    Full Text Available Aim of Study: To describe a simplified ab-interno cow-hitch suture fixation technique for repositioning decentered posterior chamber intraocular lens (PC IOL. Materials and Methods: Two cases are presented with the surgical correction of decentered and subluxated IOL. Ab-interno scleral suture fixation technique with hitch-cow knot in the eye was performed with a ciliary sulcus guide instrument and 1 year follow-up was completed. Results: Both of the patients had well centered lenses postoperatively. Corrected distant and near visual acuities of the patients were improved. There was no significant postoperative complication. In the follow-up period of 1 year, no evidence of suture erosion was found. Conclusions: Ab-interno scleral suture loop fixation with hitch-cow knot in the eye was effective in repositioning decentered or subluxated PC IOLs with excellent postoperative centered lenses and visual outcomes.

  6. 21 CFR 886.4300 - Intraocular lens guide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Intraocular lens guide. 886.4300 Section 886.4300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4300 Intraocular lens guide. (a) Identification. An intraocular lens guide is a device...

  7. Capsular bag opacification with a new accommodating intraocular lens.

    Science.gov (United States)

    Floyd, Anne M; Werner, Liliana; Liu, Erica; Stallings, Shannon; Ollerton, Andrew; Leishman, Lisa; Bodnar, Zachary; Morris, Caleb; Mamalis, Nick

    2013-09-01

    To evaluate the biocompatibility and capsular bag opacification of an accommodating intraocular lens (IOL) containing large haptic elements that separate the anterior and posterior capsules. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Bilateral phacoemulsification with IOL implantation was performed in 6 New Zealand rabbits. Each animal received a study (accommodating) IOL and a control (1-piece hydrophobic acrylic) IOL. Eyes were examined at the slitlamp from 1 day through 6 weeks postoperatively. The globes were then enucleated and evaluated grossly. Capsular bag opacification was scored from the posterior aspect (Miyake-Apple view). The eyes were then processed for complete histopathologic evaluation. At 6 weeks, the mean posterior capsule opacification (PCO) clinical score was 0.5 ± 0.3 (SD) in the study group and 3.0 ± 0.9 in the control group (P=.001, 2-tail paired t test). Anterior capsule opacification was practically absent in the study group and mild in the control group. Miyake-Apple posterior view showed a mean central PCO score of 0 ± 0 in the study group and 3.0 ± 1.1 in the control group (P=.001), peripheral PCO score of 0.7 ± 0.4 and 3.5 ± 0.8 (P=.0006), respectively, and Soemmerring ring score of 2.3 ± 0.8 and 7.0 ± 2.8 (P=.01), respectively. Histopathology showed no signs of toxicity in any eye. The study IOL maintained an expanded capsular bag secondary to the large size of the haptic elements, which appears to prevent capsular bag opacification. Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. Pigment dispersion glaucoma induced by the chafing effect of intraocular lens haptics in Asian eyes.

    Science.gov (United States)

    Hong, Ying; Sun, Yan-Xiu; Qi, Hong; Zhou, Ji-Chao; Hao, Yan-Sheng

    2013-03-01

    To study the possible mechanism and treatment for pigment dispersion glaucoma (PDG) caused by single-piece acrylic (SPA) intraocular lens (IOL) ciliary sulcus fixation in Asian eyes. Patients referred for PDG caused by SPA IOL ciliary sulcus fixation to our hospital from April 2005 to June 2011 were included. The patients' general information, IOL type, interval between initial surgery and PDG occurrence, examination findings, antiglaucoma medicine regimen and surgical interventions were recorded. In total, six eyes from five Chinese patients were included in this study. The intraocular pressure (IOP) increased 19-30 days after cataract surgery and was not satisfactorily controlled with antiglaucoma medication. Dense pigmentation was deposited on the IOLs and on the anterior chamber angle. IOL haptic chafing was noted on the rear iris surface. IOL repositioning in the capsular bag was performed in three eyes and was combined with trabeculectomy in two eyes with progressive glaucoma. An IOL exchange with three-piece IOL ciliary sulcus fixation was performed in the other three eyes. Scanning electron microscopy of the explanted IOLs demonstrated a rough edge on the IOL haptics. SPA IOLs were not suitable for ciliary sulcus fixation. The chafing effect of the IOL haptics on the posterior iris pigment epithelium could induce PDG in Asian eyes. IOLs should be positioned in the capsular bag or a three-piece IOL should be used instead.

  9. The M31 pixel lensing plan campaign: MACHO lensing and self-lensing signals

    Energy Technology Data Exchange (ETDEWEB)

    Calchi Novati, S.; Scarpetta, G. [Istituto Internazionale per gli Alti Studi Scientifici (IIASS), Via Pellegrino 19, I-84019 Vietri Sul Mare (Italy); Bozza, V. [Dipartimento di Fisica E. R. Caianiello, Università di Salerno, Via Giovanni Paolo II 132, I-84084 Fisciano (Italy); Bruni, I.; Gualandi, R. [INAF, Osservatorio Astronomico di Bologna, Via Ranzani 1, I-40127 Bologna (Italy); Dall' Ora, M. [INAF, Osservatorio Astronomico di Capodimonte, Salita Moiariello 16, I-80131 Napoli (Italy); De Paolis, F.; Ingrosso, G.; Nucita, A.; Strafella, F. [Dipartimento di Matematica e Fisica E. De Giorgi, Università del Salento, CP 193, I-73100 Lecce (Italy); Dominik, M. [SUPA, University of St Andrews, School of Physics and Astronomy, North Haugh, St Andrews, KY16 9SS (United Kingdom); Jetzer, Ph. [Institute for Theoretical Physics, University of Zürich, Winterthurerstrasse 190, 8057 Zürich (Switzerland); Mancini, L. [Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany); Safonova, M.; Subramaniam, A. [Indian Institute of Astrophysics, Bangalore 560 034 (India); Sereno, M. [Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, Corso Duca degli Abruzzi 24, I-10129 Torino (Italy); Gould, A. [Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States); Collaboration: PLAN Collaboration

    2014-03-10

    We present the final analysis of the observational campaign carried out by the PLAN (Pixel Lensing Andromeda) collaboration to detect a dark matter signal in form of MACHOs through the microlensing effect. The campaign consists of about 1 month/year observations carried out over 4 years (2007-2010) at the 1.5 m Cassini telescope in Loiano (Astronomical Observatory of BOLOGNA, OAB) plus 10 days of data taken in 2010 at the 2 m Himalayan Chandra Telescope monitoring the central part of M31 (two fields of about 13' × 12.'6). We establish a fully automated pipeline for the search and the characterization of microlensing flux variations. As a result, we detect three microlensing candidates. We evaluate the expected signal through a full Monte Carlo simulation of the experiment completed by an analysis of the detection efficiency of our pipeline. We consider both 'self lensing' and 'MACHO lensing' lens populations, given by M31 stars and dark matter halo MACHOs, in M31 and the Milky Way, respectively. The total number of events is consistent with the expected self-lensing rate. Specifically, we evaluate an expected signal of about two self-lensing events. As for MACHO lensing, for full 0.5(10{sup –2}) M {sub ☉} MACHO halos, our prediction is for about four (seven) events. The comparatively small number of expected MACHO versus self-lensing events, together with the small number statistics at our disposal, do not enable us to put strong constraints on that population. Rather, the hypothesis, suggested by a previous analysis, on the MACHO nature of OAB-07-N2, one of the microlensing candidates, translates into a sizeable lower limit for the halo mass fraction in form of the would-be MACHO population, f, of about 15% for 0.5 M {sub ☉} MACHOs.

  10. Intraocular Silicone Oil Masquerading as Terson Syndrome

    Directory of Open Access Journals (Sweden)

    Navid Elmi Sadr

    2016-01-01

    Full Text Available Introduction. Terson syndrome is described as intraocular hemorrhage in association with any type of intracranial hemorrhage and is associated with higher mortality rate and vision loss. Intraocular hemorrhage in Terson syndrome may be diagnosed using computed tomography but there are false positive results. Silicone oil which is widely used for internal tamponade of complicated retinal detachments has high attenuation on computed tomography and hyperintensity on T1-weighted magnetic resonance imaging that can mimic intraocular hemorrhage. This report shows that silicone oil is another origin of false positive results in interpreting CT findings for detecting Terson syndrome. Case Report. A 71-year-old diabetic woman presented with loss of consciousness. Brain computed tomography revealed right cerebellar hemorrhage and ventricular hemorrhage and hyperdensity in vitreous cavity of the left eye that was initially interpreted as vitreous hemorrhage. Terson syndrome was the initial diagnosis but ophthalmoscopic examination and brain MRI showed that the left eye had silicone oil tamponade. Conclusion. Without knowing the history of previous vitreoretinal surgery, CT scan findings of intraocular silicone oil may be interpreted as vitreous hemorrhage. In patients with concomitant intracranial hemorrhage, it can masquerade as Terson syndrome.

  11. Associations with intraocular pressure across Europe

    DEFF Research Database (Denmark)

    Khawaja, Anthony P; Springelkamp, Henriët; Creuzot-Garcher, Catherine

    2016-01-01

    Raised intraocular pressure (IOP) is the most important risk factor for developing glaucoma, the second commonest cause of blindness globally. Understanding associations with IOP and variations in IOP between countries may teach us about mechanisms underlying glaucoma. We examined cross-sectional...

  12. Intraocular lens in a fighter aircraft pilot.

    OpenAIRE

    Loewenstein, A; Geyer, O; Biger, Y; Bracha, R; Shochat, I; Lazar, M.

    1991-01-01

    A pseudophakic pilot of the Israeli air force flying an F-15 (Eagle) aircraft was followed up for three years. He experienced about 100 flying hours, 5% of the time under high g stress. The intraocular lens did not dislocate and no complications were observed. It seems that flying high performance fighter aircraft is not contraindicated in pseudophakic pilots.

  13. VISUAL ACUITY AND CLINICAL REFRACTION FOLLOWING IMPLANTATION OF VARIOUS MULTIFOCAL INTRAOCULAR LENSES

    Directory of Open Access Journals (Sweden)

    N. N. Temirov

    2015-01-01

    Full Text Available Aim. To analyze visual acuity, clinical refraction, and defocusing tolerance after the implantation of monofocal IOL with rotational asymmetric optic (Lentis Mplus 313 MF compared with Acrysof ReSTOR SN6AD1.Materials and methods. Phacoemulsification was performed in a total of 194 patients (288 eyes, i.e., 144 patients (188 eyes with cataract and 50 patients (100 eyes with presbyopia and high ametropia. The patients were divided into two groups. Study group included 132 patients (194 eyes implanted with Lentis Mplus while control group included 62 patients (94 eyes implanted with Acrysof ReSTOR. Uncorrected distance (5 m, intermediate (50‑70 cm, and near (20‑40 cm visual acuity under photopic (85 cd/m2 and mesopic (8 cd/m2 conditions were measured, objective and subjective refractometry were performed, and defocusing tolerance was evaluated.Results. Postoperatively, uncorrected distance and near visual acuity was high while intermediate visual acuity was moderately low. Lentis Mplus patients had better near and intermediate visual acuity under mesopic conditions as compared with Acrysof ReSTOR patients. Emmetropia (target refraction was achieved in 90.2% of study group patients and in 87.2% of control group patients. In patients implanted with Lentis Mplus, refraction was measured by subjective method. Optimal A-constant for Lentis Mplus and Acrysof ReSTOR was 118.0 and 118.6, respectively. Under defocusing, Lentis Mplus patients had better visual acuity than Acrysof ReSTOR patients. This indirectly confirms better intermediate vision.Conclusions. Lentis Mplus provides better vision at various distances that does not almost depend on light levels and induces minimal dysphotopsia. 

  14. VISUAL ACUITY AND CLINICAL REFRACTION FOLLOWING IMPLANTATION OF VARIOUS MULTIFOCAL INTRAOCULAR LENSES

    OpenAIRE

    N. N. Temirov; N. E. Temirov

    2015-01-01

    Aim. To analyze visual acuity, clinical refraction, and defocusing tolerance after the implantation of monofocal IOL with rotational asymmetric optic (Lentis Mplus 313 MF) compared with Acrysof ReSTOR SN6AD1.Materials and methods. Phacoemulsification was performed in a total of 194 patients (288 eyes), i.e., 144 patients (188 eyes) with cataract and 50 patients (100 eyes) with presbyopia and high ametropia. The patients were divided into two groups. Study group included 132 patients (194 eyes...

  15. Primary and secondary implantation of scleral-fixated posterior chamber intraocular lenses in adult patients

    Directory of Open Access Journals (Sweden)

    Zuleyha Yalniz-Akkaya

    2014-01-01

    Conclusion: Both primary and secondary scleral-fixated PCIOL implantations can provide favorable visual outcomes with lower complication rates. An important consideration is the appropriate timing for scleral fixation, taking into account the patient′s characteristics and the course of the operation.

  16. Visual performance after the implantation of a new trifocal intraocular lens

    Directory of Open Access Journals (Sweden)

    Vryghem JC

    2013-10-01

    intraocular lenses improves the intermediate vision with minimal visual discomfort for the patient.Keywords: lens implantation, trifocal diffractive intraocular lens, third focus, diffractive multifocal

  17. Optimizing distance image quality of an aspheric multifocal intraocular lens using a comprehensive statistical design approach.

    Science.gov (United States)

    Hong, Xin; Zhang, Xiaoxiao

    2008-12-01

    The AcrySof ReSTOR intraocular lens (IOL) is a multifocal lens with state-of-the-art apodized diffractive technology, and is indicated for visual correction of aphakia secondary to removal of cataractous lenses in adult patients with/without presbyopia, who desire near, intermediate, and distance vision with increased spectacle independence. The multifocal design results in some optical contrast reduction, which may be improved by reducing spherical aberration. A novel patent-pending approach was undertaken to investigate the optical performance of aspheric lens designs. Simulated eyes using human normal distributions were corrected with different lens designs in a Monte Carlo simulation that allowed for variability in multiple surgical parameters (e.g. positioning error, biometric variation). Monte Carlo optimized results indicated that a lens spherical aberration of -0.10 microm provided optimal distance image quality.

  18. Optical ensemble analysis of intraocular lens performance through a simulated clinical trial with ZEMAX.

    Science.gov (United States)

    Zhao, Huawei

    2009-01-01

    A ZEMAX model was constructed to simulate a clinical trial of intraocular lenses (IOLs) based on a clinically oriented Monte Carlo ensemble analysis using postoperative ocular parameters. The purpose of this model is to test the feasibility of streamlining and optimizing both the design process and the clinical testing of IOLs. This optical ensemble analysis (OEA) is also validated. Simulated pseudophakic eyes were generated by using the tolerancing and programming features of ZEMAX optical design software. OEA methodology was verified by demonstrating that the results of clinical performance simulations were consistent with previously published clinical performance data using the same types of IOLs. From these results we conclude that the OEA method can objectively simulate the potential clinical trial performance of IOLs.

  19. Fabrication of nanoscale electrostatic lenses

    Science.gov (United States)

    Sinno, I.; Sanz-Velasco, A.; Kang, S.; Jansen, H.; Olsson, E.; Enoksson, P.; Svensson, K.

    2010-09-01

    The fabrication of cylindrical multi-element electrostatic lenses at the nanoscale presents a challenge; they are high-aspect-ratio structures that should be rotationally symmetric, well aligned and freestanding, with smooth edges and flat, clean surfaces. In this paper, we present the fabrication results of a non-conventional process, which uses a combination of focused gallium ion-beam milling and hydrofluoric acid vapor etching. This process makes it possible to fabricate nanoscale electrostatic lenses down to 140 nm in aperture diameter and 4.2 µm in column length, with a superior control of the geometry as compared to conventional lithography-based techniques.

  20. Characterizing intraocular tumors with photoacoustic imaging

    Science.gov (United States)

    Xu, Guan; Xue, Yafang; Gursel, Zeynep; Slimani, Naziha; Wang, Xueding; Demirci, Hakan

    2016-03-01

    Intraocular tumors are life-threatening conditions. Long-term mortality from uveal melanoma, which accounts for 80% of primary intraocular tumors, could be as high as 25% depending on the size, ciliary body involvement and extraocular extension. The treatments of intraocular tumors include eye-sparing approaches such as radiotherapy and thermotherapy, and the more aggressive enucleation. The accurate diagnosis of intraocular tumors is thereby critical in the management and follow-up of the patients. The diagnosis of intraocular tumors is usually based on clinical examination with acoustic backscattering based ultrasonography. By analyzing the high frequency fluctuations within the ultrasound (US) signals, microarchitecture information inside the tumor can be characterized. However, US cannot interrogate the histochemical components formulating the microarchitecture. One representative example is the inability of US imaging (and other contemporary imaging modalities as well) in differentiating nevoid and melanoma cells as the two types of cells possesses similar acoustic backscattering properties. Combining optical and US imaging, photoacoustic (PA) measurements encode both the microarchitecture and histochemical component information in biological tissue. This study attempts to characterize ocular tumors by analyzing the high frequency signal components in the multispectral PA images. Ex vivo human eye globes with melanoma and retinoblastoma tumors were scanned using less than 6 mJ per square centimeters laser energy with tunable range of 600-1700 nm. A PA-US parallel imaging system with US probes CL15-7 and L22-14 were used to acquire the high frequency PA signals in real time. Preliminary results show that the proposed method can identify uveal melanoma against retinoblastoma tumors.

  1. In vitro and in vivo evaluation of novel implantation technology in hydrogel contact lenses for controlled drug delivery.

    Science.gov (United States)

    Maulvi, Furqan A; Lakdawala, Dhara H; Shaikh, Anjum A; Desai, Ankita R; Choksi, Harsh H; Vaidya, Rutvi J; Ranch, Ketan M; Koli, Akshay R; Vyas, Bhavin A; Shah, Dinesh O

    2016-03-28

    Glaucoma is commonly treated using eye drops, which is highly inefficient due to rapid clearance (low residence time) from ocular surface. Contact lenses are ideally suited for controlled drug delivery to cornea, but incorporation of any drug loaded particulate system (formulation) affect the optical and physical property of contact lenses. The objective of the present work was to implant timolol maleate (TM) loaded ethyl cellulose nanoparticle-laden ring in hydrogel contact lenses that could provide controlled drug delivery at therapeutic rates without compromising critical lens properties. TM-implant lenses were developed, by dispersing TM encapsulated ethyl cellulose nanoparticles in acrylate hydrogel (fabricated as ring implant) and implanted the same in hydrogel contact lenses (sandwich system). The TM-ethyl cellulose nanoparticles were prepared by double emulsion method at different ratios of TM to ethyl cellulose. The X-ray diffraction studies revealed the transformation of TM to amorphous state. In vitro release kinetic data showed sustained drug release within the therapeutic window for 168h (NP 1:3 batch) with 150μg loading. Cytotoxicity and ocular irritation study demonstrated the safety of TM-implant contact lenses. In vivo pharmacokinetic studies in rabbit tear fluid showed significant increase in mean residence time (MRT) and area under curve (AUC), with TM-implant contact lenses in comparison to eye drop therapy. In vivo pharmacodynamic data in rabbit model showed sustained reduction in intra ocular pressure for 192h. The study demonstrated the promising potential of implantation technology to treat glaucoma using contact lenses, and could serve as a platform for other ocular diseases.

  2. Photochemistry of acrylates at 222 nm

    Science.gov (United States)

    Knolle, Wolfgang; Naumov, Sergej; Madani, Mohamed; von Sonntag, Clemens

    2005-07-01

    Excimer lamps as monochromatic UV sources with an intense short-wavelength emission (especially KrCl∗, 222 nm) allow a photoinitiator-free initiation of the acrylate polymerisation. Laser photolysis (KrCl∗ excimer laser, pulse width 20 ns, up to 5 mJ per pulse) gives rise to similar transient spectra (λmax ≈ 280 nm) for all acrylates studied. As the rather unspecific spectra do not allow conclusions as to the main reaction channel, a product study has been performed by GC-MS following steady-state photolysis of acrylate solutions in acetonitrile, methanol and n-hexane. Somewhat unexpected, α-cleavage seems to be a main reaction channel, and quantum chemical calculations show that such a reaction can occur from either the excited singlet state or the unrelaxed triplet state, but not from the relaxed triplet state that is observed spectroscopically. A reaction scheme accounting for the observed products is presented.

  3. Iris-claw intraocular lens implantation: Anterior chamber versus retropupillary implantation

    Science.gov (United States)

    Helvacı, Sezer; Demirdüzen, Selahaddin; Öksüz, Hüseyin

    2016-01-01

    Purpose: To compare the outcomes of anterior chamber and retropupillary implantation of iris-claw Artisan intraocular lenses (IOL). Design: Prospective, randomized, single-blinded study. Patients and Methods: Forty eyes of forty aphakic patients were enrolled. Patients were randomized into two groups. Each group includes twenty patients. Group 1 received anterior chamber Artisan IOL implantation. Group 2 received retropupillary Artisan IOL implantation. Preoperative and postoperative corrected distance visual acuity (CDVA), intraocular pressure (IOP), and all complications were noted and compared at 6 months follow-up. Results: Each two groups obtained a significant improvement in CDVA (P < 0.05). Four patients in Group 1 and five patients in Group 2 had significant but nonpermanent increase at IOP values. There were one and two pupillary irregularity in Group 1 and Group 2, respectively. In one patient, a shallow and inferior located retinal detachment were encountered in anterior chamber group. Conclusions: The results were not significantly different between the two fixation techniques for iris-claw lens. The surgery procedure is dependent to surgeon experience and eye's conditions. PMID:26953023

  4. Sutureless intrascleral intraocular lens fixation with lamellar dissection of scleral tunnel

    Directory of Open Access Journals (Sweden)

    Kawaji T

    2016-01-01

    Full Text Available Takahiro Kawaji,1,2 Tomoki Sato,2 Hidenobu Tanihara11Department of Ophthalmology, Faculty of Life Sciences, Kumamoto University, Chuo-ku, 2Sato Eye & Internal Medicine Clinic, Kumamoto, JapanPurpose: To report the results of sutureless scleral fixation of a posterior chamber intraocular lens (IOL by using our developed simple technique.Methods: We retrospectively reviewed the medical records of 48 eyes of 47 patients who underwent sutureless intrascleral IOL fixation by using our modified technique. A 25-gauge microvitreoretinal knife was used to perform sclerotomies and create limbus-parallel scleral tunnels with lamellar dissection in which the haptics were fixed.Results: The IOLs were fixed and centered well. The mean follow-up period was 26.7 months. Postoperative complications included smooth vitreous hemorrhage in four eyes (8.3%, cystoid macular edema in two eyes (4.2%, and iris capture of the IOL in two eyes (4.2%. No other complications, such as breakage of the IOL, spontaneous IOL dislocation, or retinal detachment, were detected during the follow-up period.Conclusion: The lamellar dissection of the limbus-parallel scleral tunnel can simplify the forceps-assisted introduction of the haptics into the scleral tunnel, and this technique seemed to be safe.Keywords: intraocular lenses, ophthalmologic surgical procedures, intrascleral fixation, sutureless fixation

  5. Fabrication of nanoscale electrostatic lenses

    NARCIS (Netherlands)

    Sinno, I.; Sanz-Velasco, A.; Kang, S.; Jansen, H.; Olsson, E.; Enoksson, P.; Svensson, K.

    2010-01-01

    The fabrication of cylindrical multi-element electrostatic lenses at the nanoscale presents a challenge; they are high-aspect-ratio structures that should be rotationally symmetric, well aligned and freestanding, with smooth edges and flat, clean surfaces. In this paper, we present the fabrication r

  6. Weak lensing and cosmological investigation

    CERN Document Server

    Acquaviva, V

    2005-01-01

    In the last few years the scientific community has been dealing with the challenging issue of identifying the dark energy component. We regard weak gravitational lensing as a brand new, and extremely important, tool for cosmological investigation in this field. In fact, the features imprinted on the cosmic microwave background radiation by the lensing from the intervening distribution of matter represent a pretty unbiased estimator, and can thus be used for putting constraints on different dark energy models. This is true in particular for the magnetic-type B-modes of CMB polarization, whose unlensed spectrum at large multipoles (l approximately=1000) is very small even in presence of an amount of gravitational waves as large as currently allowed by the experiments: therefore, on these scales the lensing phenomenon is the only responsible for the observed power, and this signal turns out to be a faithful tracer of the dark energy dynamics. We first recall the formal apparatus of the weak lensing in extended t...

  7. Irlen Lenses and Reading Difficulties.

    Science.gov (United States)

    Hoyt, Creig S.

    1990-01-01

    The article reviews three studies (EC 600 064-066) evaluating the effectiveness of using Irlen tinted lenses with reading-disabled persons. The studies are individually critiqued, and recommendations are offered concerning the methodology of further research. Stressed is the need to determine whether a specific syndrome of scotopic sensitivity…

  8. Optics Demonstrations Using Cylindrical Lenses

    Science.gov (United States)

    Ivanov, Dragia; Nikolov, Stefan

    2015-01-01

    In this paper we consider the main properties of cylindrical lenses and propose several demonstrational experiments that can be performed with them. Specifically we use simple glasses full of water to demonstrate some basic geometrical optics principles and phenomena. We also present some less standard experiments that can be performed with such…

  9. Advantages of toric scleral lenses.

    NARCIS (Netherlands)

    Visser, E.S.; Visser, R.; Lier, H.J.J. van

    2006-01-01

    PURPOSE: The purpose of this study was to investigate whether back surface toric scleral lenses stabilized (i.e., returned to their original position after rotation) and how long the return times were. Return time was studied in relation with actual wearing time and comfort; moreover, the performanc

  10. Gravitational lensing by gravitational waves

    OpenAIRE

    Bisnovatyi-Kogan, G. S.; Tsupko, O. Yu.

    2008-01-01

    Gravitational lensing by gravitational wave is considered. We notice that although final and initial direction of photons coincide, displacement between final and initial trajectories occurs. This displacement is calculated analytically for the plane gravitational wave pulse. Estimations for observations are discussed.

  11. Concepts for stereoselective acrylate insertion

    KAUST Repository

    Neuwald, Boris

    2013-01-23

    Various phosphinesulfonato ligands and the corresponding palladium complexes [{((PaO)PdMeCl)-μ-M}n] ([{( X1-Cl)-μ-M}n], (PaO) = κ2- P,O-Ar2PC6H4SO2O) with symmetric (Ar = 2-MeOC6H4, 2-CF3C6H4, 2,6-(MeO)2C6H3, 2,6-(iPrO)2C 6H3, 2-(2′,6′-(MeO)2C 6H3)C6H4) and asymmetric substituted phosphorus atoms (Ar1 = 2,6-(MeO)2C6H 3, Ar2 = 2′-(2,6-(MeO)2C 6H3)C6H4; Ar1 = 2,6-(MeO)2C6H3, Ar2 = 2-cHexOC 6H4) were synthesized. Analyses of molecular motions and dynamics by variable temperature NMR studies and line shape analysis were performed for the free ligands and the complexes. The highest barriers of ΔGa = 44-64 kJ/mol were assigned to an aryl rotation process, and the flexibility of the ligand framework was found to be a key obstacle to a more effective stereocontrol. An increase of steric bulk at the aryl substituents raises the motional barriers but diminishes insertion rates and regioselectivity. The stereoselectivity of the first and the second methyl acrylate (MA) insertion into the Pd-Me bond of in situ generated complexes X1 was investigated by NMR and DFT methods. The substitution pattern of the ligand clearly affects the first MA insertion, resulting in a stereoselectivity of up to 6:1 for complexes with an asymmetric substituted phosphorus. In the consecutive insertion, the stereoselectivity is diminished in all cases. DFT analysis of the corresponding insertion transition states revealed that a selectivity for the first insertion with asymmetric (P aO) complexes is diminished in the consecutive insertions due to uncooperatively working enantiomorphic and chain end stereocontrol. From these observations, further concepts are developed. © 2012 American Chemical Society.

  12. 40 CFR 721.329 - Halogenated benzyl ester acrylate (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Halogenated benzyl ester acrylate... Specific Chemical Substances § 721.329 Halogenated benzyl ester acrylate (generic). (a) Chemical substance... halogenated benzyl ester acrylate (PMN P-90-1527) is subject to reporting under this section for...

  13. 40 CFR 721.10180 - Trifunctional acrylic ester (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Trifunctional acrylic ester (generic... Specific Chemical Substances § 721.10180 Trifunctional acrylic ester (generic). (a) Chemical substance and... acrylic ester (PMN P-04-692) is subject to reporting under this section for the significant new...

  14. 21 CFR 175.210 - Acrylate ester copolymer coating.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylate ester copolymer coating. 175.210 Section... COATINGS Substances for Use as Components of Coatings § 175.210 Acrylate ester copolymer coating. Acrylate ester copolymer coating may safely be used as a food-contact surface of articles intended for...

  15. SYNTHESIS OF BIOCOMPATIBLE ACRYLIC POLYMERS HAVING ASPIRIN-MOIETIES

    Institute of Scientific and Technical Information of China (English)

    LI Fumian; GU Zhongwei; FENG Xinde(S. T. Voong)

    1983-01-01

    Several new monomers, β-(acetylsalicylyloxy)ethyl methacrylate, β-(acetylsalicylyloxy)propyl methacrylate, β-(acetylsalicylyloxy)ethyl acrylate, β-hydroxy-γ-(acetylsalicylyloxy)propyl methacrylate, β-hydroxy-γ-(acetylsalicylyloxy)propyl acrylate have been synthesized from aspirin with corresponding hydroxyalkyl or glycidyl acrylates, and then polymerized by free radical initiator.

  16. 21 CFR 176.110 - Acrylamide-acrylic acid resins.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Acrylamide-acrylic acid resins. 176.110 Section 176... Substances for Use Only as Components of Paper and Paperboard § 176.110 Acrylamide-acrylic acid resins. Acrylamide-acrylic acid resins may be safely used as components of articles intended for use in producing...

  17. 40 CFR 721.324 - Alkoxylated acrylate polymer (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Alkoxylated acrylate polymer (generic... Substances § 721.324 Alkoxylated acrylate polymer (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as alkoxylated acrylate polymer...

  18. Amylase catalyzed synthesis of glycosyl acrylates and their polymerization

    NARCIS (Netherlands)

    Kloosterman, Wouter M.J.; Jovanovic, Danijela; Brouwer, Sander; Loos, Katja

    2014-01-01

    The enzymatic synthesis of novel (di)saccharide acrylates from starch and 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate and 4-hydroxybutyl acrylate (2-HEA, 2-HEMA and 4-HBA) catalyzed by various commercially available amylase preparations is demonstrated. Both liquefaction and saccharificatio

  19. Investigation of Acrylic Acid at High Pressure using Neutron Diffraction

    DEFF Research Database (Denmark)

    Johnston, Blair F.; Marshall, William G.; Parsons, Simon

    2014-01-01

    This article details the exploration of perdeuterated acrylic acid at high pressure using neutron diffraction. The structural changes that occur in acrylic acid-d4 are followed via diffraction and rationalised using the Pixel method. Acrylic acid undergoes a reconstructive phase transition to a n...

  20. Thermal lensing of laser materials

    Science.gov (United States)

    Davis, Mark J.; Hayden, Joseph S.

    2014-10-01

    This paper focuses on the three main effects that can induce wave-front distortion due to thermal lensing in laser gain media: 1) thermo-optic (dn/dT); 2) stress-optic; and 3) surface deformation (e.g., "end-bulging" of a laser rod). Considering the simple case of a side-pumped cylindrical rod which is air- or water-cooled along its length, the internal temperature distribution has long been known to assume a simple parabolic profile. Resulting from this are two induced refractive index variations due to thermo-optic and stress-optic effects that also assume a parabolic profile, but generally not of the same magnitude, nor even of the same sign. Finally, a small deformation on the rod ends can induce a small additional lensing contribution. We had two goals in this study: a) use finite-element simulations to verify the existing analytical expressions due to Koechner1 and Foster and Osterink; and b) apply them to glasses from the SCHOTT laser glass portfolio. The first goal was a reaction to more recent work by Chenais et al. who claimed Koechner made an error in his analysis with regard to thermal stress, throwing into doubt conclusions within studies since 1970 which made use of his equations. However, our re-analysis of their derivations, coupled with our FE modeling, confirmed that the Koechner and Foster and Osterink treatments are correct, and that Chenais et al. made mistakes in their derivation of the thermally-induced strain. Finally, for a nominal laser rod geometry, we compared the thermally-induced optical distortions in LG-680, LG-750, LG-760, LG-770, APG-1, and APG-2. While LG-750, -760, and -770 undergo considerable thermo-optic lensing, their stress-optic lensing is nearly of the same magnitude but of opposite sign, leading to a small total thermal lensing signature.

  1. Characterization of sand lenses embedded in tills

    DEFF Research Database (Denmark)

    Kessler, Timo Christian; Klint, K.E.S.; Nilsson, B.

    2012-01-01

    of the various types of sand lenses is discussed, primarily in relation to the depositional and glaciotectonic processes they underwent. Detailed characterization of sand lenses facilitates such interpretations. Finally, the observations are linked to a more general overview of the distribution of sand lenses......Tills dominate large parts of the superficial sediments on the Northern hemisphere. These glacial diamictons are extremely heterogeneous and riddled with fractures and lenses of sand or gravel. The frequency and geometry of sand lenses within tills are strongly linked to glaciodynamic processes...... occurring in various glacial environments. This study specifically focuses on the appearance and spatial distribution of sand lenses in tills. It introduces a methodology on how to measure and characterize sand lenses in the field with regard to size, shape and degree of deformation. A set of geometric...

  2. 人工晶体眼异常眩光幻影的研究进展%Research Progress in Pseudophakic Dysphotopsia Associated with Intraocular Lens

    Institute of Scientific and Technical Information of China (English)

    吴来伟

    2011-01-01

    Dysphotopsia ( glare, halos and shadows ) associated with intraocular lenses can degrade the visual performance following cataract surgery. Pseudophakic dysphotopsia is caused by four factors, including intraocular lens design, surgical factors, patient physical factors, and central adaptation. Positive dysphotopsia can be minimized by a larger optic, textured intraocular lens edge, optiEdge edge, and lower posterior capsule opacification. Besides, incision location, and iris - intraocular lens distance may play an important role in negative dysphotopsia. For the treatment of dysphotopsia,six months of clinical observation is necessary. Patients with severe and persistent dysphotopsia need to replace intraocular lens or to implant a piggyback intraocular lens in the ciliary sulcus.%白内障术后发生的眩光、光晕、阴影等眩光幻影问题成为影响视觉质量的重要因素.影响人工晶体眼眩光幻影的因素有晶体设计、手术因素、患者生理因素和心理适应.预防后发性白内障、晶体边缘纹理化、采用前圆后方边缘设计、使用更大的晶体光学面可以减少正像眩光幻影的发生.而手术切口位置和虹膜-晶体间距等可能是负像眩光幻影产生的影响因素.对于眩光幻影的治疗,6个月的临床观察是必要的,症状严重且持续者可考虑晶体置换或睫状沟植入另一枚驼背式人工晶体.

  3. EDITORIAL: Focus on Gravitational Lensing

    Science.gov (United States)

    Jain, Bhuvnesh

    2007-11-01

    Gravitational lensing emerged as an observational field following the 1979 discovery of a doubly imaged quasar lensed by a foreground galaxy. In the 1980s and '90s dozens of other multiply imaged systems were observed, as well as time delay measurements, weak and strong lensing by galaxies and galaxy clusters, and the discovery of microlensing in our galaxy. The rapid pace of advances has continued into the new century. Lensing is currently one of best techniques for finding and mapping dark matter over a wide range of scales, and also addresses broader cosmological questions such as understanding the nature of dark energy. This focus issue of New Journal of Physics presents a snapshot of current research in some of the exciting areas of lensing. It provides an occasion to look back at the advances of the last decade and ahead to the potential of the coming years. Just about a decade ago, microlensing was discovered through the magnification of stars in our galaxy by invisible objects with masses between that of Jupiter and a tenth the mass of the Sun. Thus a new component of the mass of our galaxy, dubbed MACHOs, was established (though a diffuse, cold dark matter-like component is still needed to make up most of the galaxy mass). More recently, microlensing led to another exciting discovery—of extra-solar planets with masses ranging from about five times that of Earth to that of Neptune. We can expect many more planets to be discovered through ongoing surveys. Microlensing is the best technique for finding Earth mass planets, though it is not as productive overall as other methods and does not allow for follow up observations. Beyond planet hunting, microlensing has enabled us to observe previously inaccessible systems, ranging from the surfaces of other stars to the accretion disks around the black holes powering distant quasars. Galaxies and galaxy clusters at cosmological distances can produce dramatic lensing effects: multiple images of background galaxies

  4. Intraocular foreign body removal: Case report

    Directory of Open Access Journals (Sweden)

    Kovačević Igor

    2013-01-01

    Full Text Available Introduction. An intraocular foreign body may traumatize the eye mechanically, introduce infection or exert other toxic effects on the intraocular structures. Removal of a metallic intraocular foreign bodies (IOFB use an internal (vitrectomy followed by forceps or internal magnet use or external approach (large electromagnet. Outline of Cases. A 51-year-old man sustained injury of the left eye by a metal foreign body. On admission visual acuity was normal (VOS=1.0 and intraocular tension was within normal limits (TOS=10 mmHg. Nasal scleral entry wound was noticed. Ultrasound of the left eye was done, which confirmed existence of IOFB laying nasally, next to the ciliary body. Extraction of IOFB with a big electric magnet was done. Visual acuity on discharge was the same (VOS=1.0. Another man, aged 30 years, came to the clinic after injury of the left eye by a foreign body. On admission visual acuity was VOS=L+P+ (light and projection, TOS=44 mmHg (higher, traumatic cataract, scleral entry wound, corneal edema, existence of IOFB and initial endophtalmitis. Lensectomia and vitrectomia via pars plana with IOFB extraction were done. Visual acuity on discharge was VOS=5/60 with +6.50 Dsph = 0.3-0.4; TOS=17 mmHg. Conclusion. Magnet removal is indicated in patients when IOFB is laying free in the vitreous body or stopped near the entry wound during injury without other complications. Internal approach - pars plana vitrectomy with forceps removal is used when IOFB is stuck either on the peripheral or posterior part of the retina or if there are some of aforementioned complications.

  5. Environmental standards for intraocular lens implantation.

    Science.gov (United States)

    Crawford, B A; Kaufman, D V

    1984-02-01

    Successful implantation of prosthetic devices depends upon their freedom from postoperative inflammation and infection. Techniques and lessons learned in orthopaedic and other implant surgery should be applied to intraocular lens implantation. The avoidance of contamination by particles and micro-organisms is one essential principle of the surgical procedure. Practical steps are described to reduce both types of contamination. These measures taken together are recommended for adoption as a standard of environmental safety for lens implantation.

  6. Bilateral Pseudoexfoliation Deposits on Intraocular Lens Implants

    OpenAIRE

    Elena Bonafonte Marquez; Sergio Bonafonte Royo

    2015-01-01

    We present a rare case of bilateral pseudoexfoliative deposits on both intraocular lens (IOL) implants in an 83-year-old woman with no other associated pathology, 5 years after cataract surgery. Pseudoexfoliation syndrome is the most common cause of secondary open-angle glaucoma worldwide and these deposits are usually found on the natural lens. The fact that pseudoexfoliative deposits have been found on IOL implants implies the need for a thorough examination in pseudophakic patients, for i...

  7. Introduction to the development of intraocular lens

    Science.gov (United States)

    Li, Yifan; Peng, Runling; Hu, Shuilan; Wei, Maowei; Chen, Jiabi

    2013-08-01

    In order to cure the cataract disease or injuries in eyes, intraocular lens(IOL) has been studied all the time to replace the crystalline lens in human eyes. Researches on IOL are started early from 19th century, and it develops greatly in the hundreds years after. This article introduces several main kinds of IOLs that appear in the development history of IOL, and raises the double-liquid zoom IOL based on electrowetting, which will be the trend of IOL study.

  8. Effect of an ultraviolet-filtering intraocular lens on cystoid macular edema

    Energy Technology Data Exchange (ETDEWEB)

    Kraff, M.C.; Sanders, D.R.; Jampol, L.M.; Lieberman, H.L.

    1985-03-01

    A prospective double-masked study of 301 patients was undertaken to compare the effect of ultraviolet (UV) filtering in implant intraocular lenses (IOL) on the angiographic incidence of cystoid macular edema (CME) in patients undergoing extracapsular cataract extraction. Patients were randomized to receive either a posterior chamber IOL that contained UV-absorbing chromophore or an identical IOL which did not contain such a chromophore. All patients were scheduled for fluorescein angiography between three and six months after surgery; 228 angiograms were obtained that were readable for the presence or absence of angiographic CME. The mean interval following surgery was 4.3 months. The incidence of CME was 18.8% (21 of 112) in patients who received lenses without UV-filtering chromophore and 9.5% (11 of 116) in patients who received IOLs that contained UV-filtering chromophore. These findings show that UV-filtering-IOLs resulted in a statistically significant decrease in the incidence of CME. The presence or absence of the UV-filtering chromophore did not, however, significantly affect visual acuity in the early postoperative period.

  9. Acrylic Tanks for Stunning Chemical Demonstrations

    Science.gov (United States)

    Mirholm, Alexander; Ellervik, Ulf

    2009-01-01

    We describe the use of acrylic tanks (400 x 450 x 27 mm) for visualization of chemical demonstrations in aqueous solutions. Examples of well-suited demonstrations are oscillating reactions, pH indicators, photochemical reduction of Lauth's violet, and chemoluminiscent reactions. (Contains 1 figure.)

  10. ACRYLATE-AMIDE FOAM CARDIOVASCULAR PROSTHESES.

    Science.gov (United States)

    thoracic and abdominal aorta. The use of a composite construction utilizing acrylate-amide foam is being evaluated in prostheses for mitral valve ...bleeding. The success of the initial experimental work has led to a clinical trial in which 99 replacement , bypass, or patch-angioplasty procedures... replacement , superior vena cava patch venoplasty, and esophageal replacement . (Author)

  11. Probe Tack of Model Acrylic Adhesives

    Science.gov (United States)

    Lakrout, Hamed; Creton, Costantino; Ahn, Dongchan; Shull, Kenneth R.

    1998-03-01

    In a probe tack test, a flat punch comes in contact with a thin layer of elastomer deposited on a substrate. The punch is then removed from the substrate at a constant crosshead velocity. In these conditions, the adhesive layer is highly constrained and extensive cavitation will occur when a negative hydrostatic pressure is applied. Commercial latexes of Poly2-EthylHexyl Acrylate (PEHA) and homemade Polyn-ButylAcrylate have been tested and characterized by dynamic mechanical measurements. Tests have been performed using several temperatures and debonding rates. Stress vs. strain curves have been related to debonding mechanisms through video observation. For both of these acrylic adhesives, temperature and debonding rate have opposite effects on adhesion energy and maximum stress of debonding, behavior which is typical for a viscoelastic system. In case of the PEHA, the addition of 2.5% of acrylic acid did not affect the rheological properties. However the type of the fracture changed from cohesive to adhesive. Moreover the growth of the cavities changed from viscous fingering of few cavities to circular growth of numerous small cavities.

  12. [Changes in intraocular pressure depending on posture].

    Science.gov (United States)

    Barac, Ramona; Pop, Monica; Tătaru, C; Gheorghe, A; Bădescu, Silvia; Stanciu, Maria; Burcea, M

    2014-01-01

    Glaucoma is an important eye disease that, left untreated, causes irreversible blindness by affecting optic nerve threads. Decreasing intraocular pressure and maintaining it at a low level throughout the day is one of the objectives of antiglaucoma therapy. This is a prospective study conducted on a sample of 80 patients who presented at "Emergency Eye Hospital" Bucharest between 1st of December 2013 30th of July 2014. Patients were divided into two groups: 40 patients with glaucoma and 40 patients without glaucoma (control group). THE OBJECTIVE OF THE STUDY: To determine changes in intraocular pressure that may occur depending on body posture and the correlations between changes in intraocular pressure and glaucoma, obesity, hypertension. These IOP changes may be important in the progression of glaucoma regarding that one third of our time is spent on supine position during night. RESULTS AND CONCLUZIONS: IOP varies from sitting down to supine position. IOP increases in supine in most patients (with or without glaucoma) with an average of 1.25 mmHg. The increase among patients with glaucoma is higher (1.67 mmHg) compared to those without glaucoma (0.82 mmHg). In patients with hypertension and glaucoma, IOP increased with 2.62 mmHg. In patients with hypertension and obesity IOP increased with 2.5 mmHg.

  13. [A universal laser for intraocular treatment].

    Science.gov (United States)

    Pomerantzeff, O; Vallat, M; Pankratov, M M; Pflibsen, K P; Schepens, C L

    1988-01-01

    The creation of a single apparatus incorporating the different lasers applicable to intraocular pathology derives from the idea of possessing the means, with one device, of objectively comparing the effects and parameters of various lasers in order to pursue a more precise line of treatment. This has led to our fabrication of the universal intraocular laser. The word universal means the ability of the machine to act on each kind of intraocular tissues with all of the various infrared or other-colored radiations, as well as with different modalities. The unit is transportable. It only requires a source of electric power (110 or 220 V) and includes an independent cooling system. The Nd: YAG laser has selectable operating parameters: pulsed or continuous excitation, Q-switched or mode-locked mode, mirror or fiber optic transmission. It is used also as the basic system of the coloured module. The colour module can provide the three clinically useful radiations: green, red, yellow. The green (532 nm) is obtained by transmission of the I.R. beam brought a birefringent crystal (KTP). Red (650 nm) and yellow (575 nm) come from two incorporated dye lasers excited by the green radiation.

  14. Effect of aspherical and yellow tinted intraocular lens on blue-on-yellow perimetry Efeito das lentes intraoculares asféricas e com pigmentação amarela na campimetria azul-amarelo

    Directory of Open Access Journals (Sweden)

    Rodrigo França de Espíndola

    2012-10-01

    Full Text Available PURPOSE: To investigate the possible effect of aspherical or yellow tinted intraocular lens (IOL on contrast sensitivity and blue-on-yellow perimetry. METHODS: This prospective randomized bilateral double-masked clinical study included 52 patients with visually significant bilateral cataracts divided in two groups; 25 patients (50 eyes received aspherical intraocular lens in one eye and spherical intraocular lens in the fellow eye; and 27 patients (54 eyes received ultraviolet and blue light filter (yellow tinted IOL implantation in one eye and acrylic ultraviolet filter IOL in the fellow eye. The primary outcome measures were contrast sensitivity and blue-on-yellow perimetry values (mean deviation [MD] and pattern standard deviation [PSD] investigated two years after surgery. The results were compared intra-individually. RESULTS: There was a statistically significant between-group (aspherical and spherical intraocular lens difference in contrast sensitivity under photopic conditions at 12 cycles per degree and under mesopic conditions at all spatial frequencies. There were no between-group significant differences (yellow tinted and clear intraocular lens under photopic or mesopic conditions. There was no statistically significant difference between all intraocular lens in MD or PSD. CONCLUSION: Contrast sensitivity was better under mesopic conditions with aspherical intraocular lens. Blue-on-yellow perimetry did not appear to be affected by aspherical or yellow tinted intraocular lens. Further studies with a larger sample should be carried out to confirm or not that hypotheses.OBJETIVO: Investigar a possibilidade de efeitos na sensibilidade ao contraste e nos resultados da campimetria azul-amarelo com implante de uma lente intraocular (LIO asférica ou de pigmentação amarela. MÉTODOS: Trata-se de um estudo prospectivo, randomizado, duplo-mascarado, envolvendo 52 pacientes portadores de catarata senil bilateral, divididos em dois grupos; 25

  15. Large Acrylic Spherical Windows In Hyperbaric Underwater Photography

    Science.gov (United States)

    Lones, Joe J.; Stachiw, Jerry D.

    1983-10-01

    Both acrylic plastic and glass are common materials for hyperbaric optical windows. Although glass continues to be used occasionally for small windows, virtually all large viewports are made of acrylic. It is easy to uderstand the wide use of acrylic when comparing design properties of this plastic with those of glass, and glass windows are relatively more difficult to fabricate and use. in addition there are published guides for the design and fabrication of acrylic windows to be used in the hyperbaric environment of hydrospace. Although these procedures for fabricating the acrylic windows are somewhat involved, the results are extremely reliable. Acrylic viewports are now fabricated to very large sizes for manned observation or optical quality instrumen tation as illustrated by the numerous acrylic submersible vehicle hulls for hu, an occupancy currently in operation and a 3600 large optical window recently developed for the Walt Disney Circle Vision under-water camera housing.

  16. Gravitational Lensing - Einstein's Unfinished Symphony

    CERN Document Server

    Treu, Tommaso

    2014-01-01

    Gravitational lensing - the deflection of light rays by gravitating matter - has become a major tool in the armoury of the modern cosmologist. Proposed nearly a hundred years ago as a key feature of Einstein's theory of General Relativity, we trace the historical development since its verification at a solar eclipse in 1919. Einstein was apparently cautious about its practical utility and the subject lay dormant observationally for nearly 60 years. Nonetheless there has been rapid progress over the past twenty years. The technique allows astronomers to chart the distribution of dark matter on large and small scales thereby testing predictions of the standard cosmological model which assumes dark matter comprises a massive weakly-interacting particle. By measuring distances and tracing the growth of dark matter structure over cosmic time, gravitational lensing also holds great promise in determining whether the dark energy, postulated to explain the accelerated cosmic expansion, is a vacuum energy density or a...

  17. Biomimetic Gradient Index (GRIN) Lenses

    Science.gov (United States)

    2006-01-01

    optics include single lenses inspired by cephalopod (octopus) eyes and a three-lens, wide field of view, optical system for a surveillance sensor...camera. Details are easily resolv- able with the polymer lens. This lens system was installed on an Evolution unmanned aerial vehicle (UAV) with a...lens system was installed in an NRL Evolution UAV and used to record video images at a height of up to 1000 ft. The index gradients in the polymer

  18. RELICS: Reionization Lensing Cluster Survey

    Science.gov (United States)

    Coe, Dan A.; RELICS Team

    2017-01-01

    Hubble and Spitzer imaging programs observing galaxy cluster lenses have delivered some of the highest redshift galaxy candidates to date (z ~ 9 - 11, or 540 - 410 Myr after the Big Bang). These magnified galaxies are intrinsically faint, and thus more representative of the sources believed to be primarily responsible for reionization. Magnified galaxies are also observed brightly enough to be prime targets for detailed follow-up study with current and future observatories, including JWST. Building on the successes of CLASH and the Frontier Fields, we have begun RELICS, the Reionization Lensing Cluster Survey. By observing 41 massive clusters for the first time at infrared wavelengths, RELICS will deliver more of the best and brightest high-redshift candidates to the community in time for the November 2017 JWST GO Cycle 1 call for proposals. I will present our early results. I will also discuss prospects for JWST to follow-up known candidates and discover new galaxies at even higher redshifts (z > 11). The discovery efficiency gains from lensing will be even more pronounced at z > 11 if luminosity function faint end slopes are steeper than alpha ~ -2, as suggested by current models and observational extrapolations.

  19. Gravitational lensing in plasmic medium

    Energy Technology Data Exchange (ETDEWEB)

    Bisnovatyi-Kogan, G. S., E-mail: gkogan@iki.rssi.ru; Tsupko, O. Yu., E-mail: tsupko@iki.rssi.ru [Russian Academy of Sciences, Space Research Institute (Russian Federation)

    2015-07-15

    The influence of plasma on different effects of gravitational lensing is reviewed. Using the Hamiltonian approach for geometrical optics in a medium in the presence of gravity, an exact formula for the photon deflection angle by a black hole (or another body with a Schwarzschild metric) embedded in plasma with a spherically symmetric density distribution is derived. The deflection angle in this case is determined by the mutual combination of different factors: gravity, dispersion, and refraction. While the effects of deflection by the gravity in vacuum and the refractive deflection in a nonhomogeneous medium are well known, the new effect is that, in the case of a homogeneous plasma, in the absence of refractive deflection, the gravitational deflection differs from the vacuum deflection and depends on the photon frequency. In the presence of a plasma nonhomogeneity, the chromatic refractive deflection also occurs, so the presence of plasma always makes gravitational lensing chromatic. In particular, the presence of plasma leads to different angular positions of the same image if it is observed at different wavelengths. It is discussed in detail how to apply the presented formulas for the calculation of the deflection angle in different situations. Gravitational lensing in plasma beyond the weak deflection approximation is also considered.

  20. Uncontrolled Selling of Contact Lenses

    Directory of Open Access Journals (Sweden)

    Cem Sundu

    2015-05-01

    Full Text Available Objectives: To evaluate the opticians’ perspective about selling and applying contact lenses (CL in the provincial centre of Mersin. Materials and Methods: Twenty opticians who work in the 4 main districts in the provincial centre of Mersin were included in the study. A questionnaire form which was prepared before was filled out by the participants. Results: Seventy-eight percent of the opticians were selling CL without prescription, whereas 25% also carried out its fitting. Seventyfive percent of the participants did not get any education about contact lenses, while 65% of them were feeling themselves disqualified about CLs. Furthermore, half of the participants did not have enough knowledge about the complications associated with CL usage and 75% of them wanted to receive information about CLs. Conclusion: As a result of the questionnaire, we found out that a significant part of the participants were both selling and fitting contact lenses without prescription. We believe that auditing the opticians is as important as educating the contact lens users. (Turk J Ophthalmol 2015; 45: 102-104

  1. Comparison of Trans-scleral Fixation of PMMA and Foldable Intraocular Lens in Children

    Institute of Scientific and Technical Information of China (English)

    Yuping Zou; Zhende Lin; Bo Feng; Shaozhen Li

    2001-01-01

    Purpose: To observe the difference of the effects of PMMA and foldable intraocular lenses (IOLs) trans-sclerally fixed in pediatric eyes. Methods: Thirty-two children (43 eyes) who had undergone trans-scleral fixation of IOL were retrospected, of whom 5 children were implanted PMMA IOL in both eyes, 6children were implanted PMMA IOL in one eye and foldable IOL in the other eye, 12children were implanted foldable IOL in one eye and 9 chilrden were implanted PMMA IOL in one eye. Mean age was 5.3 years ( range 2.5 ~ 12 years ). Twelve children had traumatic cataract and the others congenital cataract before lens extraction. Results: Foldable group (18 eyes ): Mean follow-up was 12.1 months. Visual acuity (VA): compared with the best corrected VA before IOL fixation, postoperative best corrected VA improved in 16 eyes, remained unchanged in 2 eyes. In 14 eyes, one or two stitches were needed to seal the incision. Complications: Severe anterior chamber reaction was seen in 3 eyes. Intraocular bleeding was found in 3 eyes. IOL decentration was detected in 1 eye. Iris capture of IOL was seen in one eye. PMMA group (25 eyes ):Mean follow-up was 20.3 months. Visual acuity (VA): compared with the best corrected VA before IOL fixation, postoperative best corrected VA improved in 19 eyes,remained unchanged in 5 eyes and got worse in one eye. In 24 eyes, one to three stitches were needed to seal the incision. Complications: Severe anterior chamber reaction was seen in 5 eyes. Intraocular bleeding was found in 4 eyes. IOL decentration was seen in one eye. Iris capture of IOL was seen in 3 eyes. Intraocular pressure elevated in one eye. Conclusion: Our study shows that trans-scleral fixation of IOL is a safe procedure in pediatric eyes. Foldable IOL showed similar effect compared with PMMA IOL in pediatric trans-scleral fixation. Eye Science 2001; 17:61 ~ 64.

  2. Visual acuity and patient satisfaction at varied distances and lighting conditions after implantation of an aspheric diffractive multifocal one-piece intraocular lens

    Science.gov (United States)

    Chang, Daniel H

    2016-01-01

    Purpose The aim of the study is to evaluate the visual acuity and patient satisfaction at varied distances under photopic and mesopic lighting conditions in patients bilaterally implanted with aspheric diffractive multifocal one-piece intraocular lenses. Methods In this retrospective–prospective study, 16 patients with a mean age of 66.2±9.2 years (range: 50–81 years) who had undergone bilateral phacoemulsification surgery with implantation of a Tecnis multifocal one-piece intraocular lens (ZMB00) were evaluated. Monocular and binocular uncorrected and distance-corrected visual acuities were measured at distance (20 ft), intermediate (70–80 cm), and near (35–40 cm) under photopic (85 cd/m2) and mesopic (3 cd/m2) lighting conditions and were compared using the paired t-test. All patients also completed a subjective questionnaire. Results At a mean follow-up of 9.5±3.9 months, distance, near, and intermediate visual acuity improved significantly from preoperative acuity. Under photopic and mesopic conditions, 93.8% and 62.5% of patients, respectively, had binocular uncorrected intermediate visual acuity of 20/40 or better, and 62.5% and 31.3% of patients had binocular uncorrected near visual acuity of 20/20 or better. All patients were satisfied with their overall vision without using glasses and/or contact lenses when compared with before surgery. A total of 87.5% of patients reported no glare and 68.8% of patients reported no halos around lights at night. Conclusion Tecnis multifocal one-piece intraocular lenses provide good distance, intermediate, and near visual acuity under photopic as well as mesopic lighting conditions. High levels of spectacle independence with low levels of photic phenomenon were achieved, resulting in excellent patient satisfaction. PMID:27536061

  3. Clinical analysis of 49 cases with intraocular lens dislocation%人工晶状体脱位49例临床分析

    Institute of Scientific and Technical Information of China (English)

    王海燕; 庞秀琴; 何雷; 裴雪婷; 王绍莉; 卢海

    2012-01-01

    Objective To discuss the clinical characteristics of intraocular lens (IOL) dislocation. Design Retrospective cases series. Participants 49 eyes (49 cases) of intraocular lens dislocation in Beijing Tongren Hospital from 2004 to 2011. Methods Clinical data of intraocular lens dislocation were reviewed retrospectively. Main Outcome Measures Age, original disease, history of disease, position and type of intraocular lens, cause, surgical method, and complication. Results Majority of 49 cases of intraocular lens dislocation were cases with surgery of age-related cataract (46.9%) and traumatic cataract (28.6%). 6 cases with dislocation of intraocular lens with ciliary sulcus fixation happened 1 year after surgery. Majority of intraocular lenses dislocated located in vitreous body (53.1%) and "C" loop (89.8%). 75.5% of causes were original disease and surgery. Ciliary sulcus fixation or re-fixation of intraocular lens (47 eyes, 95.9%) could achieve good centration and stability of the intraocular lens. Naked vision of 0.1 or more accounted for 59.6% at 2 weeks after fixation or re-fixation. Conclusion Intraocular lens dislocation is related with original disease and surgery. Ciliary sulcus fixation of intraocular lens is an effective strategy to treat intraocular lens dislocation. But intraocular lens with ciliary sulcus fixation still happens to dislocate. (Ophthalmol CHN, 2012, 21: 47-51)%目的 探讨人工晶状体(IOL)脱位的临床特点.设计 回顾性病例系列.研究对象 北京同仁医院2004-2011年治疗的IOL脱位49例49眼.方法 对IOL脱位患者的临床资料进行同顾性分析.主要指标 年龄、原IOL植入原因,发病时间,脱位IOL位置及类型,IOL脱位诱因,手术治疗方法及并发症.结果 49眼IOL脱位中,老年性白内障和外伤性白内障摘除联合IOL植入术者较多,分别占46.9%、28.6%.6例睫状沟固定IOL脱位均发生于手术1年后.脱位IOL53.1%位于玻璃体腔内.89.8

  4. Discovery of eight lensing clusters of galaxies

    CERN Document Server

    Liang, S M; Han, J L; Jiang, Y Y

    2013-01-01

    Clusters of galaxies have a huge mass which can act as gravitational lenses. Galaxies behind clusters can be distorted to form arcs in images by the lenses. Herein a search was done for giant lensed arcs by galaxy clusters using the SDSS data. By visually inspecting SDSS images of newly identified clusters in the SDSS DR8 and Stripe 82 data, we discover 8 strong lensing clusters together with additional 3 probable and 6 possible cases. The lensed arcs show bluer colors than the member galaxies of clusters. The masses and optical luminosities of galaxy clusters interior to the arcs are calculated, and the mass-to-light ratios are found to be in the range of a few tens of M_Solar/L_Solar, consistent with the distribution of previously known lensing clusters.

  5. Planck 2015 results. XV. Gravitational lensing

    CERN Document Server

    Ade, P A R; Arnaud, M; Ashdown, M; Aumont, J; Baccigalupi, C; Banday, A J; Barreiro, R B; Bartlett, J G; Bartolo, N; Battaner, E; Benabed, K; Benoît, A; Benoit-Lévy, A; Bernard, J -P; Bersanelli, M; Bielewicz, P; Bonaldi, A; Bonavera, L; Bond, J R; Borrill, J; Bouchet, F R; Boulanger, F; Bucher, M; Burigana, C; Butler, R C; Calabrese, E; Cardoso, J -F; Catalano, A; Challinor, A; Chamballu, A; Chiang, H C; Christensen, P R; Church, S; Clements, D L; Colombi, S; Colombo, L P L; Combet, C; Couchot, F; Coulais, A; Crill, B P; Curto, A; Cuttaia, F; Danese, L; Davies, R D; Davis, R J; de Bernardis, P; de Rosa, A; de Zotti, G; Delabrouille, J; Désert, F -X; Diego, J M; Dole, H; Donzelli, S; Doré, O; Douspis, M; Ducout, A; Dunkley, J; Dupac, X; Efstathiou, G; Elsner, F; Enßlin, T A; Eriksen, H K; Fergusson, J; Finelli, F; Forni, O; Frailis, M; Fraisse, A A; Franceschi, E; Frejsel, A; Galeotta, S; Galli, S; Ganga, K; Giard, M; Giraud-Héraud, Y; Gjerløw, E; González-Nuevo, J; Górski, K M; Gratton, S; Gregorio, A; Gruppuso, A; Gudmundsson, J E; Hansen, F K; Hanson, D; Harrison, D L; Henrot-Versillé, S; Hernández-Monteagudo, C; Herranz, D; Hildebrandt, S R; Hivon, E; Hobson, M; Holmes, W A; Hornstrup, A; Hovest, W; Huffenberger, K M; Hurier, G; Jaffe, A H; Jaffe, T R; Jones, W C; Juvela, M; Keihänen, E; Keskitalo, R; Kisner, T S; Kneissl, R; Knoche, J; Kunz, M; Kurki-Suonio, H; Lagache, G; Lähteenmäki, A; Lamarre, J -M; Lasenby, A; Lattanzi, M; Lawrence, C R; Leonardi, R; Lesgourgues, J; Levrier, F; Lewis, A; Liguori, M; Lilje, P B; Linden-Vørnle, M; López-Caniego, M; Lubin, P M; Macías-Pérez, J F; Maggio, G; Maino, D; Mandolesi, N; Mangilli, A; Martin, P G; Martínez-González, E; Masi, S; Matarrese, S; Mazzotta, P; McGehee, P; Meinhold, P R; Melchiorri, A; Mendes, L; Mennella, A; Migliaccio, M; Mitra, S; Miville-Deschênes, M -A; Moneti, A; Montier, L; Morgante, G; Mortlock, D; Moss, A; Munshi, D; Murphy, J A; Naselsky, P; Nati, F; Natoli, P; Netterfield, C B; Nørgaard-Nielsen, H U; Noviello, F; Novikov, D; Novikov, I; Oxborrow, C A; Paci, F; Pagano, L; Pajot, F; Paoletti, D; Pasian, F; Patanchon, G; Perdereau, O; Perotto, L; Perrotta, F; Pettorino, V; Piacentini, F; Piat, M; Pierpaoli, E; Pietrobon, D; Plaszczynski, S; Pointecouteau, E; Polenta, G; Popa, L; Pratt, G W; Prézeau, G; Prunet, S; Puget, J -L; Rachen, J P; Reach, W T; Rebolo, R; Reinecke, M; Remazeilles, M; Renault, C; Renzi, A; Ristorcelli, I; Rocha, G; Rosset, C; Rossetti, M; Roudier, G; Rowan-Robinson, M; Rubiño-Martín, J A; Rusholme, B; Sandri, M; Santos, D; Savelainen, M; Savini, G; Scott, D; Seiffert, M D; Shellard, E P S; Spencer, L D; Stolyarov, V; Stompor, R; Sudiwala, R; Sunyaev, R; Sutton, D; Suur-Uski, A -S; Sygnet, J -F; Tauber, J A; Terenzi, L; Toffolatti, L; Tomasi, M; Tristram, M; Tucci, M; Tuovinen, J; Valenziano, L; Valiviita, J; Van Tent, B; Vielva, P; Villa, F; Wade, L A; Wandelt, B D; Wehus, I K; White, M; Yvon, D; Zacchei, A; Zonca, A

    2015-01-01

    We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40 sigma), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator we detect lensing at a significance of 5 sigma. We cross-check the accuracy of our measurement using the wide frequency coverage and complementarity of the temperature and polarization measurements. Public products based on this measurement include an estimate of the lensing potential over approximately 70% of the sky, an estimate of the lensing potential power spectrum in bandpowers for the multipole range 40lensing potential power spectrum and that found in the best-fitting LCDM model based on the Planck temperature and polarization power spectra. Using the lensing likelihood alone we obtain a percent-level measurement of ...

  6. Void Profile from Planck Lensing Potential Map

    Science.gov (United States)

    Chantavat, Teeraparb; Sawangwit, Utane; Wandelt, Benjamin D.

    2017-02-01

    We use the lensing potential map from Planck CMB lensing reconstruction analysis and the “Public Cosmic Void Catalog” to measure the stacked void lensing potential. We have made an attempt to fit the HSW void profile parameters from the stacked lensing potential. In this profile, four parameters are needed to describe the shape of voids with different characteristic radii R V . However, we have found that after reducing the background noise by subtracting the average background, there is a residue lensing power left in the data. The inclusion of the environment shifting parameter, {γ }V, is necessary to get a better fit to the data with the residue lensing power. We divide the voids into two redshift bins: cmass1 (0.45Digital Sky Survey voids reside in an underdense region.

  7. METHACRYLATE AND ACRYLATE ALLERGY IN DENTAL STUDENTS.

    Directory of Open Access Journals (Sweden)

    Maya Lyapina

    2013-09-01

    Full Text Available A multitude of acrylic monomers is used in dentistry, and when dental personnel, patients or students of dental medicine become sensitized, it is of great importance to identify the dental ;acrylic preparations to which the sensitized individual can be exposed. Numerous studies confirm high incidence of sensitization to (meth acrylates in dentatal professionals, as well as in patients undergoing dental treatment and exposed to resin-based materials. Quite a few studies are available aiming to evaluate the incidence of sensitization in students of dental medicineThe purpose of the study is to evaluate the incidence of contact sensitization to some (meth acrylates in students of dental medicine at the time of their education, in dental professionals (dentists, nurses and attendants and in patients, the manifestation of co-reactivity.A total of 139 participants were included in the study, divided into four groups: occupationally exposed to (methacrylates and acrylic monomers dental professionals, 3-4 year-of-education students of dental medicine, 6th year–of-education students of dental medicine and patients with suspected or established sensitization to acrylates, without occupational exposure. All of them were patch-tested with methyl methacrylate (MMA, triethyleneglycol dimethacrylate (TREGDMA, ethyleneglycol dimethacrylate (EGDMA, 2,2-bis[4-(2-hydroxy-3-methacryloxypropoxy phenyl]propane (bis-GMA, 2-hydroxyethyl methacrylate (2-HEMA, and tetrahidrofurfuril metacrylate. The overall sensitization rates to methacrylates in the studied population are comparative high – from 25.9% for MMA to 31.7% for TREGDMA. Significantly higher incidence of sensitization in the group of 3-4 course students compared to the one in the group of dental professionals for MMA and TREGDMA was observed. Highest was the incidence of sensitization to ethyleneglycol dimethacrylate, BIS-GMA, 2-HEMA and tetrahydrofurfuryl methacrylate in the group of patients, with

  8. Incisões relaxantes limbares ou incisões no meridiano mais curvo associadas a facoemulsificação com implante de lente intra-ocular multifocal: relato de três casos Limbal relaxing incision or the more curved meridian incision associated to phacoemulsification with multifocal intraocular lens implant: three case reports

    Directory of Open Access Journals (Sweden)

    Wilson Takashi Hida

    2008-04-01

    Full Text Available O implante de lentes intra-oculares (LIOs multifocais é um grande avanço na reabilitação de pacientes permitindo boa acuidade visual sem correção óptica para longe e perto. Contudo pacientes com alguns graus de astigmatismo corneano tem indicação limitada. Este artigo relata três pacientes que foram submetidas a facoemulsificação com implante de lentes intra-oculares multifocais (AcrySof® Restor®, Alcon Labs após incisão relaxante limbar (IRL no olho dominante e incisão no eixo mais curvo da topografia no olho contralateral. Não foi encontrado nenhuma análise relacionada a dominância ocular e relaxante limbar na literatura. Acredita-se que essa associação pode ampliar as indicações de implante das lentes intra-oculares multifocais em pacientes com astigmatismo corneano significativo, devendo-se confirmar esta possibilidade por meio de futuros estudos.The use of multifocal intraocular lenses (IOLs is a great advance in the treatment of patients with cataract allowing near and distance uncorrected visual acuity recovery. However patients with some degrees of corneal astigmatism have some limitations. We present 3 cases that were indicated for phacoemulsitfication and multifocal intraocular lens implant (AcrySof® Restor®, Alcon Labs after limbal relaxing incision (LRI in the dominant eye and axis topographic incision in the fellow eye. There was no similar case report in the literature. It is believed that this association can extend the indications for multifocal intraocular lens implants in patients with significant corneal astigmatism and this possibility should be confirmed by future studies.

  9. Modified technique of endocapsular lens aspiration for severely subluxated lenses.

    Science.gov (United States)

    Khokhar, S; Aron, N; Yadav, N; Pillay, G; Agarwal, E

    2017-08-11

    PurposeSeverely subluxated crystalline lenses pose a difficult situation to anterior segment surgeons and can only be managed surgically by removal of the lens as well as the capsular bag. Several techniques have been described in literature for the management of such cases. We describe a modified technique of endocapsular lens aspiration by the limbal route for lens extraction through small incisions on the cornea.Patients and methodsThirty-two eyes of 16 consecutive patients with severely subluxated crystalline lenses were recruited in the study. All eyes underwent a modified technique of lens aspiration within the capsular bag using a single instrument, vitrectomy cutter, and irrigation cannula, followed by sacrificing of the capsular bag. The patients were either left aphakic or implanted with an open loop anterior chamber intraocular lens (ACIOL Kelman Multiflex) and prospectively followed up for a period of 3 months.ResultsThe mean age of the patients was 9 years 3 months±3 years (range 5-15 yrs). All eyes underwent complete lens aspiration within the capsular bag with no dislocation of the lens matter. ACIOL was inserted in 22 eyes (68.7%) and 10 eyes (31.2%) were left aphakic. All the surgeries were uneventful. The mean best corrected visual acuity (BCVA) at 3 months post surgery was 0.47±0.11 logMAR which was significantly better than pre-operative BCVA (P=0.001). The percentage endothelial cell loss at 3 months was 7.1%. There was no evidence of glaucoma, corneal decompensation, or retinal detachment. The astigmatism which increased from 1.45D±086 preoperatively to 3.76D±2.02 1 week post-operatively due to sutures reduced to 1.97D±0.81 post suture removal at 3 months.ConclusionThe modified technique of endocapsular lens aspiration proves to be a simple and effective method of removal of the lens-capsular bag complex in severely subluxated lenses.Eye advance online publication, 11 August 2017; doi:10.1038/eye.2017.160.

  10. Design of spherical symmetric gradient index lenses

    Science.gov (United States)

    Miñano, Juan C.; Grabovičkić, Dejan; Benítez, Pablo; González, Juan C.; Santamaría, Asunción

    2012-10-01

    Spherical symmetric refractive index distributions also known as Gradient Index lenses such as the Maxwell-Fish-Eye (MFE), the Luneburg or the Eaton lenses have always played an important role in Optics. The recent development of the technique called Transformation Optics has renewed the interest in these gradient index lenses. For instance, Perfect Imaging within the Wave Optics framework has recently been proved using the MFE distribution. We review here the design problem of these lenses, classify them in two groups (Luneburg moveable-limits and fixed-limits type), and establish a new design techniques for each type of problem.

  11. Ion exchange tempering of glass ophthalmic lenses.

    Science.gov (United States)

    Keeney, A H; Duerson, H L

    1975-08-01

    We performed low velocity drop-ball tests using 5/8-, 7/8-, and 1-inch diameter steel balls on ophthalmic crown glass lenses chemically tempered by the ion exchange process. Four representative dioptric strengths (+ 2.50 spherical, - 2.50 spherical, -2.50 cylindrical, and plano) were studied with the isolated lenses mounted, convex side up, on the American National Standards Institute Z80 test block. New ion exchange lenses exhibited a 100 to 350% greater capacity for attenuation of energy from low velocity, large size missiles than matched lenses of similar strength prepared by the conventional heat-treating and air-quenching process.

  12. Vision Loss following Intraocular Listeriosis Associated with Contaminated Cantaloupe

    Directory of Open Access Journals (Sweden)

    Mam Ibraheem

    2013-06-01

    Full Text Available Intraocular listeriosis, a rare manifestation of invasive listeriosis, has a poor visual prognosis. We report an intraocular listeriosis case related to a multistate outbreak associated with contaminated cantaloupe. Increasing awareness of rare listeriosis presentations might facilitate timely diagnosis and treatment, and case reporting can clarify medical and epidemiologic aspects of listeriosis.

  13. Vision Loss following Intraocular Listeriosis Associated with Contaminated Cantaloupe

    OpenAIRE

    Mam Ibraheem; Sushma Vance; Jackson, Kelly A.; Paul Ettestad; Chad Smelser; Benjamin Silk

    2013-01-01

    Intraocular listeriosis, a rare manifestation of invasive listeriosis, has a poor visual prognosis. We report an intraocular listeriosis case related to a multistate outbreak associated with contaminated cantaloupe. Increasing awareness of rare listeriosis presentations might facilitate timely diagnosis and treatment, and case reporting can clarify medical and epidemiologic aspects of listeriosis.

  14. Comparative Evaluation of Handheld Robot-Aided Intraocular Laser Surgery

    Science.gov (United States)

    Yang, Sungwook; MacLachlan, Robert A.; Martel, Joseph N.; Lobes, Louis A.; Riviere, Cameron N.

    2015-01-01

    This paper presents robot-aided intraocular laser surgery using a handheld robot known as Micron. The micromanipulator incorporated in Micron enables visual servoing of a laser probe, while maintaining a constant distance of the tool tip from the retinal surface. The comparative study was conducted with various control methods for evaluation of robot-aided intraocular laser surgery. PMID:27019653

  15. Primary intraocular chondrosarcoma in a dog

    Directory of Open Access Journals (Sweden)

    E. Perlmann

    2013-12-01

    Full Text Available A five-year-old male Cocker Spaniel was presented for evaluation of the right eye due to discomfort, abundant purulent discharge and progressive enlargement of the eyeball. The owner revealed that the right eye has appeared to be inflamed and smaller then the left eye for years. Ophthalmic examination revealed corneal perforation, buphthalmia and conjuctival hyperemia. Enucleating was performed due to signs of endophthalmitis and ocular discomfort. Histopathology revealed a multilobulated proliferation of chondrocytes producing hyaline cartilage with occasional pleomorphism and binucleate cells. A diagnosis of primary intraocular chondrosarcoma was done.

  16. Bilateral Pseudoexfoliation Deposits on Intraocular Lens Implants

    Directory of Open Access Journals (Sweden)

    Elena Bonafonte Marquez

    2015-01-01

    Full Text Available We present a rare case of bilateral pseudoexfoliative deposits on both intraocular lens (IOL implants in an 83-year-old woman with no other associated pathology, 5 years after cataract surgery. Pseudoexfoliation syndrome is the most common cause of secondary open-angle glaucoma worldwide and these deposits are usually found on the natural lens. The fact that pseudoexfoliative deposits have been found on IOL implants implies the need for a thorough examination in pseudophakic patients, for it could be the only sign of secondary glaucoma.

  17. How to measure intraocular pressure: applanation tonometry

    Directory of Open Access Journals (Sweden)

    Nick Astbury

    2012-01-01

    Full Text Available Unless there is a contraindication (e.g. trauma or corneal ulcer, all adults attending an eye unit should have their intraocular pressure (IOP measured. Many people with glaucoma have no symptoms and do not know they have the condition. All children who have had cataract surgery should also have their IOP measured at every follow-up visit, if possible. Finding glaucoma early allows treatment to be given which will preserve sight. Although elevated IOP is not the only sign of glaucoma, measuring it is simple and quick to do. Applanation tonometry, using a Goldmann tonometer at a slit lamp, is the preferred method (the ‘gold standard’.

  18. [Drug delivery systems for intraocular applications].

    Science.gov (United States)

    Bourges, J-L; Touchard, E; Kowalczuk, L; Berdugo, M; Thomas-Doyle, A; Bochot, A; Gomez, A; Azan, F; Gurny, R; Behar-Cohen, F

    2007-12-01

    Numerous drug delivery systems (DDSs) can be used as intraocular tools to provide a sustained and calibrated release for a specific drug. Great progress has been made on the design, biocompatibility, bioavailability, and efficacy of DDSs. Although several of them are undergoing clinical trials, a few are already on the market and could be of a routine use in clinical practice. Moreover, miniaturization of the implants makes them less and less traumatic for the eye tissues and some DDSs are now able to target certain cells or tissues specifically. An overview of ocular implants with therapeutic application potentials is provided.

  19. Implantable intraocular pressure monitoring systems: Design considerations

    KAUST Repository

    Arsalan, Muhammad

    2013-12-01

    Design considerations and limitations of implantable Intraocular Pressure Monitoring (IOPM) systems are presented in this paper. Detailed comparison with the state of the art is performed to highlight the benefits and challenges of the proposed design. The system-on-chip, presented here, is battery free and harvests energy from incoming RF signals. This low-cost design, in standard CMOS process, does not require any external components or bond wires to function. This paper provides useful insights to the designers of implantable wireless sensors in terms of design choices and associated tradeoffs. © 2013 IEEE.

  20. A New Design of a Lead-Acrylic Shield for Staff Dose Reduction in Radial and Femoral Access Coronary Catheterization.

    Science.gov (United States)

    Eder, H; Seidenbusch, M C; Treitl, M; Gilligan, P

    2015-10-01

    Today's standard radiation protection during coronary angiography and percutaneous coronary interventions is the combined use of lead acrylic shields and table-mounted lower body protection. Ambient dose measurements, however, have shown that these protection devices need improvement. Using an anthropomorphic physical phantom, various scenarios were investigated with respect to personnel exposure: a) enlarging the shield b) adding a flexible protective curtain to the bottom side of the shield, and c) application of radioprotective patient drapes. For visualization of the dose reduction effect, Monte Carlo simulations were performed. The flexible curtain in contact with the patient's body reduces the ambient dose rate at the operator's position by up to (87.5% ± 7.1) compared to the situation with the bare shield. The use of both the flexible curtain and the patient drape reduces the ambient dose rate by up to (90.8% ± 7). Similar results were achieved for the assisting personnel when they were positioned next to the operator. In addition, the enlarged shield provides better protection of the head region of tall operators. Adding a flexible protective curtain to the bottom side of the shield can protect operators from high doses, especially for body parts which are not protected by lead aprons, e.g. head, and eye lenses. This may be important with respect to lower dose limits for eye lenses in future. The protective effect in real-life working conditions is still being evaluated in an ongoing clinical study. Lead acrylic shields need improvement for a better protection of head and eye lenses. An additional flexible lead curtain at the bottom of the shield can considerably reduce the operator dose. Using the additional lead curtain, lighter protection clothing can be worn. Special eye protection may be no longer needed in most applications. © Georg Thieme Verlag KG Stuttgart · New York.

  1. N-body lensed CMB maps: lensing extraction and characterization

    CERN Document Server

    Antolini, Claudia; Martinelli, Matteo; Carbone, Carmelita; Baccigalupi, Carlo

    2013-01-01

    We reconstruct shear maps and angular power spectra from simulated weakly lensed total intensity (TT) and polarised (EB) maps of the Cosmic Microwave Background (CMB) anisotropies, obtained using Born approximated ray-tracing through the N-body simulated Cold Dark Matter (CDM) structures in the Millennium Simulations (MS). We compare the recovered signal with the ${\\Lambda}$CDM prediction, on the whole interval of angular scales which is allowed by the finite box size, extending from the degree scale to the arcminute, by applying a quadratic estimator in the flat sky limit; we consider PRISM-like instrumental specification for future generation CMB satellites, corresponding to arcminute angular resolution of 3.2' and sensitivity of 2.43 ${\\mu}$K-arcmin. The noise bias in the simulations closely follows the estimator prediction, becoming dominated by limits in the angular resolution for the EB signal, at l ${\\simeq}$ 1500. The de-biased signal shows no visible departure from predictions of the weak lensing pow...

  2. Accelerated 20-year sunlight exposure simulation of a photochromic foldable intraocular lens in a rabbit model

    Science.gov (United States)

    Werner, Liliana; Abdel-Aziz, Salwa; Peck, Carolee Cutler; Monson, Bryan; Espandar, Ladan; Zaugg, Brian; Stringham, Jack; Wilcox, Chris; Mamalis, Nick

    2011-01-01

    PURPOSE To assess the long-term biocompatibility and photochromic stability of a new photochromic hydrophobic acrylic intraocular lens (IOL) under extended ultraviolet (UV) light exposure. SETTING John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. DESIGN Experimental study. METHODS A Matrix Aurium photochromic IOL was implanted in right eyes and a Matrix Acrylic IOL without photochromic properties (n = 6) or a single-piece AcrySof Natural SN60AT (N = 5) IOL in left eyes of 11 New Zealand rabbits. The rabbits were exposed to a UV light source of 5 mW/cm2 for 3 hours during every 8-hour period, equivalent to 9 hours a day, and followed for up to 12 months. The photochromic changes were evaluated during slitlamp examination by shining a penlight UV source in the right eye. After the rabbits were humanely killed and the eyes enucleated, study and control IOLs were explanted and evaluated in vitro on UV exposure and studied histopathologically. RESULTS The photochromic IOL was as biocompatible as the control IOLs after 12 months under conditions simulating at least 20 years of UV exposure. In vitro evaluation confirmed the retained optical properties, with photochromic changes observed within 7 seconds of UV exposure. The rabbit eyes had clinical and histopathological changes expected in this model with a 12-month follow-up. CONCLUSIONS The new photochromic IOL turned yellow only on exposure to UV light. The photochromic changes were reversible, reproducible, and stable over time. The IOL was biocompatible with up to 12 months of accelerated UV exposure simulation. PMID:21241924

  3. The Scales of Gravitational Lensing

    CERN Document Server

    De Paolis, Francesco; Ingrosso, Gabriele; Manni, Luigi; Nucita, Achille; Strafella, Francesco

    2016-01-01

    After exactly a century since the formulation of the general theory of relativity, the phenomenon of gravitational lensing is still an extremely powerful method for investigating in astrophysics and cosmology. Indeed, it is adopted to study the distribution of the stellar component in the Milky Way, to study dark matter and dark energy on very large scales and even to discover exoplanets. Moreover, thanks to technological developments, it will allow the measure of the physical parameters (mass, angular momentum and electric charge) of supermassive black holes in the center of ours and nearby galaxies.

  4. The Scales of Gravitational Lensing

    Directory of Open Access Journals (Sweden)

    Francesco De Paolis

    2016-03-01

    Full Text Available After exactly a century since the formulation of the general theory of relativity, the phenomenon of gravitational lensing is still an extremely powerful method for investigating in astrophysics and cosmology. Indeed, it is adopted to study the distribution of the stellar component in the Milky Way, to study dark matter and dark energy on very large scales and even to discover exoplanets. Moreover, thanks to technological developments, it will allow the measure of the physical parameters (mass, angular momentum and electric charge of supermassive black holes in the center of ours and nearby galaxies.

  5. Natural wormholes as gravitational lenses

    CERN Document Server

    Cramer, J G; Morris, M S; Visser, M; Benford, G; Landis, G A; Cramer, John G; Forward, Robert L; Morris, Michael S; Visser, Matt; Benford, Gregory; Landis, Geoffrey A

    1995-01-01

    Visser has suggested traversable 3-dimensional wormholes that could plausibly form naturally during Big Bang inflation. A wormhole mouth embedded in high mass density might accrete mass, giving the other mouth a net *negative* mass of unusual gravitational properties. The lensing of such a gravitationally negative anomalous compact halo object (GNACHO) will enhance background stars with a time profile that is observable and qualitatively different from that recently observed for massive compact halo objects (MACHOs) of positive mass. We recommend that MACHO search data be analyzed for GNACHOs.

  6. Pulse radiolysis of aqueous solutions of ethyl acrylate and hydroxy ethyl acrylate

    Science.gov (United States)

    Safrany, A.; Biro, A.; Wojnarovits, L.

    1993-10-01

    Ethyl- and hydroxy ethyl acrylate show high reactivities with hydrated electron and hydroxyl radical intermediates of water radiolysis. The electron adduct reversibly protonate with pK values of 5.7 and 7.3. The adducts may take part in irreversible protonation at the β carbon atom forming α-carboxyl alkyl radicals. Same type of radical forms in reaction of acrylates with OH: at low concentration the adduct mainly disappear in self termination reactions. Above 5 mmol dm -1 the signals showed the startup of oligomerization.

  7. Ocular Straylight with Different Multifocal Contact Lenses

    NARCIS (Netherlands)

    Łabuz, Grzegorz; López-Gil, Norberto; van den Berg, Thomas J T P; Vargas-Martín, Fernando

    2017-01-01

    PURPOSE: Multifocal contact lenses have been growing in popularity as a modality to correct presbyopic eyes, although visual side effects such as disability glare have been reported. The objective of this study was to investigate the effect of multifocal contact lenses on disability glare by means

  8. Modern scleral lenses part I: clinical features.

    NARCIS (Netherlands)

    Visser, E.S.; Visser, R.; Lier, H.J.J. van; Otten, H.M.

    2007-01-01

    PURPOSE: To evaluate the indications for modern scleral lenses and their clinical performance in patients who were fitted with scleral lenses at the authors' practices. METHODS: In this cross-sectional survey, all the necessary data were obtained at the first follow-up visit during the 5-month study

  9. Planck 2015 results: XV. Gravitational lensing

    DEFF Research Database (Denmark)

    Ade, P. A R; Aghanim, N.; Arnaud, M.;

    2016-01-01

    We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40σ), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator, we detect lensing at a significance of 5σ. We...

  10. Optical aberrations in a gas lenses

    CSIR Research Space (South Africa)

    Mafusire, C

    2010-08-01

    Full Text Available and Security Presented at the Laser Beam Shaping XI, 2010 SPIE Optics + Photonics Annual Conference San Diego Convention Centre San Diego, California 1-5 August 2010 Page 2 © CSIR 2010 www.csir.co.za Gas Lenses • Gas Lenses and M...

  11. Geometry of weak lensing of CMB polarization

    CERN Document Server

    Challinor, A D; Challinor, Anthony; Chon, Gayoung

    2002-01-01

    Hu has presented a harmonic-space method for calculating the effects of weak gravitational lensing on the cosmic microwave background (CMB) over the full sky. Computing the lensed power spectra to first order in the deflection power requires one to formulate the lensing displacement beyond the tangent-space approximation. We point out that for CMB polarization this displacement must undergo geometric corrections on the spherical sky to maintain statistical isotropy of the lensed fields. Although not discussed by Hu, these geometric effects are implicit in his analysis. However, there they are hidden by an overly-compact notation that is both unconventional and rather confusing. Here we aim to ameliorate this deficiency by providing a rigorous derivation of the lensed spherical power spectra.

  12. Gravitational Lensing of Cosmic Microwave Background Polarization

    CERN Document Server

    Ade, P A R; Anthony, A E; Arnold, K; Barron, D; Boettger, D; Borrill, J; Chapman, S; Chinone, Y; Dobbs, M; Elleflot, T; Errard, J; Fabbian, G; Feng, C; Flanigan, D; Gilbert, A; Grainger, W; Halverson, N W; Hasegawa, M; Hattori, K; Hazumi, M; Holzapfel, W L; Hori, Y; Howard, J; Hyland, P; Inoue, Y; Jaehnig, G C; Jaffe, A; Keating, B; Kermish, Z; Keskitalo, R; Kisner, T; Jeune, M Le; Lee, A T; Linder, E; Lungu, M; Matsuda, F; Matsumura, T; Meng, X; Miller, N J; Morii, H; Moyerman, S; Myers, M J; Navaroli, M; Nishino, H; Paar, H; Peloton, J; Quealy, E; Rebeiz, G; Reichardt, C L; Richards, P L; Ross, C; Schanning, I; Schenck, D E; Sherwin, B; Shimizu, A; Shimmin, C; Shimon, M; Siritanasak, P; Smecher, G; Spieler, H; Stebor, N; Steinbach, B; Stompor, R; Suzuki, A; Takakura, S; Tomaru, T; Wilson, B; Yadav, A; Zahn, O

    2013-01-01

    Primary fluctuations in both temperature and polarization of the Cosmic Microwave Background (CMB) reflect the properties of the Universe from the Big Bang until the photons decoupled from matter 380,000 years later. These primary fluctuations are then lensed by large-scale structures (such as clusters of galaxies and filaments of dark matter), with the result that the distribution and properties of dark matter, including the masses of neutrinos, can be determined more accurately by extracting the lensing information than through studying the primary fluctuations alone. Polarization lensing can give cleaner, higher resolution results than temperature lensing. The correlation of lensed CMB polarization with large-scale structure, traced through the Cosmic Infrared Background, was recently detected; however, this correlation does not trace all structure and depends on the relationship between the infrared flux from the galaxies and the underlying mass distribution. Here we report the detection of gravitational ...

  13. On aberration in gravitational lensing

    CERN Document Server

    Sereno, M

    2008-01-01

    It is known that a relative translational motion between the deflector and the observer affects gravitational lensing. In this paper, a lens equation is obtained to describe such effects on actual lensing observables. Results can be easily interpreted in terms of aberration of light-rays. Both radial and transverse motions with relativistic velocities are considered. The lens equation is derived by first considering geodesic motion of photons in the rest-frame Schwarzschild spacetime of the lens, and, then, light-ray detection in the moving observer's frame. Due to the transverse motion images are displaced and distorted in the observer's celestial sphere, whereas the radial velocity along the line of sight causes an effective re-scaling of the lens mass. The Einstein ring is distorted to an ellipse whereas the caustics in the source plane are still point-like. Either for null transverse motion or up to linear order in velocities, the critical curve is still a circle with its radius corrected by a factor (1+z...

  14. Ray optics of generalized lenses.

    Science.gov (United States)

    Chaplain, Gregory J; Macauley, Gavin; Bělín, Jakub; Tyc, Tomáš; Cowie, Euan N; Courtial, Johannes

    2016-05-01

    We study the ray optics of generalized lenses (glenses), which are ideal thin lenses generalized to have different object- and image-sided focal lengths, and the most general light-ray-direction-changing surfaces that stigmatically image any point in object space to a corresponding point in image space. Gabor superlenses [UK patent541,753 (1940); J. Opt. A1, 94 (1999)JOAOF81464-425810.1088/1464-4258/1/1/013] can be seen as pixelated realizations of glenses. Our analysis is centered on the nodal point. Whereas the nodal point of a thin lens always resides in the lens plane, that of a glens can reside anywhere on the optical axis. Utilizing the nodal point, we derive simple equations that describe the mapping between object and image space and the light-ray-direction change. We demonstrate our findings with the help of ray-tracing simulations. Glenses allow novel optical instruments to be realized, at least theoretically, and our results facilitate the design and analysis of such devices.

  15. Cosmology with Strong Lensing Systems

    CERN Document Server

    Cao, Shuo; Gavazzi, Raphaël; Piórkowska, Aleksandra; Zhu, Zong-Hong

    2015-01-01

    In this paper, we assemble a catalog of 118 strong gravitational lensing systems from SLACS, BELLS, LSD and SL2S surveys and use them to constrain the cosmic equation of state. In particular we consider two cases of dark energy phenomenology: $XCDM$ model where dark energy is modeled by a fluid with constant $w$ equation of state parameter and in Chevalier - Polarski - Linder (CPL) parametrization where $w$ is allowed to evolve with redshift: $w(z) = w_0 + w_1 \\frac{z}{1+z}$. We assume spherically symmetric mass distribution in lensing galaxies, but relax the rigid assumption of SIS model in favor to more general power-law index $\\gamma$, also allowing it to evolve with redshifts $\\gamma(z)$. Our results for the $XCDM$ cosmology show the agreement with values (concerning both $w$ and $\\gamma$ parameters) obtained by other authors. We go further and constrain the CPL parameters jointly with $\\gamma(z)$. The resulting confidence regions for the parameters are much better than those obtained with a similar metho...

  16. The Search for Lensed Supernovae

    Science.gov (United States)

    Kohler, Susanna

    2017-01-01

    Type Ia supernovae that have multiple images due to gravitational lensing can provide us with a wealth of information both about the supernovae themselves and about our surrounding universe. But how can we find these rare explosions?Clues from Multiple ImagesWhen light from a distant object passes by a massive foreground galaxy, the galaxys strong gravitational pull can bend the light, distorting our view of the backgroundobject. In severe cases, this process can cause multiple images of the distant object to appear in the foreground lensing galaxy.An illustration of gravitational lensing. Light from the distant supernova is bent as it passes through a giant elliptical galaxy in the foreground, causing multiple images of the supernova to appear to be hosted by the elliptical galaxy. [Adapted from image by NASA/ESA/A. Feild (STScI)]Observations of multiply-imaged Type Ia supernovae (explosions that occur when white dwarfs in binary systems exceed their maximum allowed mass) could answer a number of astronomical questions. Because Type Ia supernovae are standard candles, distant, lensed Type Ia supernovae can be used to extend the Hubble diagram to high redshifts. Furthermore, the lensing time delays from the multiply-imaged explosion can provide high-precision constraints on cosmological parameters.The catch? So far, weve only found one multiply-imaged Type Ia supernova: iPTF16geu, discovered late last year. Were going to need a lot more of them to develop a useful sample! So how do we identify themutiply-imaged Type Ias among the many billions of fleeting events discovered in current and future surveys of transients?Searching for AnomaliesAbsolute magnitudes for Type Ia supernovae in elliptical galaxies. None are expected to be above -20 in the B band, so if we calculate a magnitude for a Type Ia supernova thats larger than this, its probably not hosted by the galaxy we think it is! [Goldstein Nugent 2017]Two scientists from University of California, Berkeley and

  17. Planck 2015 results. XV. Gravitational lensing

    Science.gov (United States)

    Planck Collaboration; Ade, P. A. R.; Aghanim, N.; Arnaud, M.; Ashdown, M.; Aumont, J.; Baccigalupi, C.; Banday, A. J.; Barreiro, R. B.; Bartlett, J. G.; Bartolo, N.; Basak, S.; Battaner, E.; Benabed, K.; Benoît, A.; Benoit-Lévy, A.; Bernard, J.-P.; Bersanelli, M.; Bielewicz, P.; Bock, J. J.; Bonaldi, A.; Bonavera, L.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bucher, M.; Burigana, C.; Butler, R. C.; Calabrese, E.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Chiang, H. C.; Christensen, P. R.; Church, S.; Clements, D. L.; Colombi, S.; Colombo, L. P. L.; Combet, C.; Couchot, F.; Coulais, A.; Crill, B. P.; Curto, A.; Cuttaia, F.; Danese, L.; Davies, R. D.; Davis, R. J.; de Bernardis, P.; de Rosa, A.; de Zotti, G.; Delabrouille, J.; Désert, F.-X.; Diego, J. M.; Dole, H.; Donzelli, S.; Doré, O.; Douspis, M.; Ducout, A.; Dunkley, J.; Dupac, X.; Efstathiou, G.; Elsner, F.; Enßlin, T. A.; Eriksen, H. K.; Fergusson, J.; Finelli, F.; Forni, O.; Frailis, M.; Fraisse, A. A.; Franceschi, E.; Frejsel, A.; Galeotta, S.; Galli, S.; Ganga, K.; Giard, M.; Giraud-Héraud, Y.; Gjerløw, E.; González-Nuevo, J.; Górski, K. M.; Gratton, S.; Gregorio, A.; Gruppuso, A.; Gudmundsson, J. E.; Hansen, F. K.; Hanson, D.; Harrison, D. L.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Herranz, D.; Hildebrandt, S. R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Hornstrup, A.; Hovest, W.; Huffenberger, K. M.; Hurier, G.; Jaffe, A. H.; Jaffe, T. R.; Jones, W. C.; Juvela, M.; Keihänen, E.; Keskitalo, R.; Kisner, T. S.; Kneissl, R.; Knoche, J.; Kunz, M.; Kurki-Suonio, H.; Lagache, G.; Lähteenmäki, A.; Lamarre, J.-M.; Lasenby, A.; Lattanzi, M.; Lawrence, C. R.; Leonardi, R.; Lesgourgues, J.; Levrier, F.; Lewis, A.; Liguori, M.; Lilje, P. B.; Linden-Vørnle, M.; López-Caniego, M.; Lubin, P. M.; Macías-Pérez, J. F.; Maggio, G.; Maino, D.; Mandolesi, N.; Mangilli, A.; Maris, M.; Martin, P. G.; Martínez-González, E.; Masi, S.; Matarrese, S.; McGehee, P.; Meinhold, P. R.; Melchiorri, A.; Mendes, L.; Mennella, A.; Migliaccio, M.; Mitra, S.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Morgante, G.; Mortlock, D.; Moss, A.; Munshi, D.; Murphy, J. A.; Naselsky, P.; Nati, F.; Natoli, P.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; Noviello, F.; Novikov, D.; Novikov, I.; Oxborrow, C. A.; Paci, F.; Pagano, L.; Pajot, F.; Paoletti, D.; Pasian, F.; Patanchon, G.; Perdereau, O.; Perotto, L.; Perrotta, F.; Pettorino, V.; Piacentini, F.; Piat, M.; Pierpaoli, E.; Pietrobon, D.; Plaszczynski, S.; Pointecouteau, E.; Polenta, G.; Popa, L.; Pratt, G. W.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Rachen, J. P.; Reach, W. T.; Rebolo, R.; Reinecke, M.; Remazeilles, M.; Renault, C.; Renzi, A.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Rossetti, M.; Roudier, G.; Rowan-Robinson, M.; Rubiño-Martín, J. A.; Rusholme, B.; Sandri, M.; Santos, D.; Savelainen, M.; Savini, G.; Scott, D.; Seiffert, M. D.; Shellard, E. P. S.; Spencer, L. D.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sutton, D.; Suur-Uski, A.-S.; Sygnet, J.-F.; Tauber, J. A.; Terenzi, L.; Toffolatti, L.; Tomasi, M.; Tristram, M.; Tucci, M.; Tuovinen, J.; Valenziano, L.; Valiviita, J.; Van Tent, B.; Vielva, P.; Villa, F.; Wade, L. A.; Wandelt, B. D.; Wehus, I. K.; White, M.; Yvon, D.; Zacchei, A.; Zonca, A.

    2016-09-01

    We present the most significant measurement of the cosmic microwave background (CMB) lensing potential to date (at a level of 40σ), using temperature and polarization data from the Planck 2015 full-mission release. Using a polarization-only estimator, we detect lensing at a significance of 5σ. We cross-check the accuracy of our measurement using the wide frequency coverage and complementarity of the temperature and polarization measurements. Public products based on this measurement include an estimate of the lensing potential over approximately 70% of the sky, an estimate of the lensing potential power spectrum in bandpowers for the multipole range 40 ≤ L ≤ 400, and an associated likelihood for cosmological parameter constraints. We find good agreement between our measurement of the lensing potential power spectrum and that found in the ΛCDM model that best fits the Planck temperature and polarization power spectra. Using the lensing likelihood alone we obtain a percent-level measurement of the parameter combination σ8Ω0.25m = 0.591 ± 0.021. We combine our determination of the lensing potential with the E-mode polarization, also measured by Planck, to generate an estimate of the lensing B-mode. We show that this lensing B-mode estimate is correlated with the B-modes observed directly by Planck at the expected level and with a statistical significance of 10σ, confirming Planck's sensitivity to this known sky signal. We also correlate our lensing potential estimate with the large-scale temperature anisotropies, detecting a cross-correlation at the 3σ level, as expected because of dark energy in the concordance ΛCDM model.

  18. A novel technique to release sticking haptic of a single-piece hydrophobic acrylic IOL using irrigation-aspiration probe.

    Science.gov (United States)

    Khokhar, Sudarshan Kumar; Midha, Neha; Patil, Bharat; Nayak, Bhagabat; Simakurthy, Sriram

    2016-01-01

    To describe a novel technique to release sticking haptic of a single-piece hydrophobic acrylic intraocular lens (IOL) using irrigation-aspiration (I/A) probe. In our technique, the I/A probe is introduced into the anterior chamber on Visco mode. Using the aspiration port of the I/A probe, the sticking haptic is held at its tip and suction force is built up until occlusion is noted. Then the haptic is nudged towards the center of the IOL along its curve. After the haptic is free from optic, the suction is released. Several techniques have been described to release the sticking haptic such as squeezing the haptic at the site where it sticks to the IOL or using Sinskey hook for releasing the adhesion. These techniques require extra manipulation of the IOL by introduction of surgical instruments. In our technique, we used the I/A probe itself for separating the sticky haptic successfully. This technique allows separation of sticking haptic without any extra instrumentation, thus reducing intraocular maneuvering and total surgery time.

  19. [Iritis with destabilization of the intraocular pressure due to dislocation of a posterior chamber intraocular lens].

    Science.gov (United States)

    Handzel, D M

    2012-04-01

    This report concerns the case of a 67-year-old male patient who underwent uncomplicated phacoemulsification with implantation of a posterior chamber intraocular lens (IOL). After an interval of 2 months the patient developed iritis together with an uncontrollable increase in intraocular pressure. After a detailed examination a dislocated haptic of the IOL was identified as the cause of the symptoms. The dislocation had led to uveitis-glaucoma-hyphema syndrome although no hemorrhage was observed. In addition to this complication the haptic had arroded the zonular complex which made implantation of an anterior chamber lens necessary. Although improvements in operating techniques, lens materials and designs have been made uveitis-glaucoma-hyphema syndrome has to be kept in mind. Surgical intervention is the only therapeutic option.

  20. Assessing the effect of laser beam width on quantitative evaluation of optical properties of intraocular lens implants

    Science.gov (United States)

    Walker, Bennett N.; James, Robert H.; Chakravarty, Aurin; Calogero, Don; Ilev, Ilko K.

    2014-05-01

    The design and manufacture of intraocular lenses (IOLs) depend upon the identification and quantitative preclinical evaluation of key optical properties and environmental parameters. The confocal laser method (CLM) is a new technique for measuring IOL optical properties, such as dioptric power, optical quality, refractive index, and geometrical parameters. In comparison to competing systems, the CLM utilizes a fiber-optic confocal laser design that significantly improves the resolution, accuracy, and repeatability of optical measurements. Here, we investigate the impact of changing the beam diameter on the CLM platform for the evaluation of IOL dioptric powers. Due to the Gaussian intensity profile of the CLM laser beam, the changes in focal length and dioptric power associated with changes in beam diameter are well within the tolerances specified in the ISO IOL standard. These results demonstrate some of the advanced potentials of the CLM toward more effectively and quantitatively evaluating IOL optical properties.

  1. MicroRNA profiling in intraocular medulloepitheliomas.

    Directory of Open Access Journals (Sweden)

    Deepak P Edward

    Full Text Available To study the differential expression of microRNA (miRNA profiles between intraocular medulloepithelioma (ME and normal control tissue (CT.Total RNA was extracted from formalin fixed paraffin embedded (FFPE intraocular ME (n=7 and from age matched ciliary body controls (n=8. The clinical history and phenotype was recorded. MiRNA profiles were determined using the Affymetrix GeneChip miRNA Arrays analyzed using expression console 1.3 software. Validation of significantly dysregulated miRNA was confirmed by quantitative real-time PCR. The web-based DNA Intelligent Analysis (DIANA-miRPath v2.0 was used to perform enrichment analysis of differentially expressed (DE miRNA gene targets in Kyoto Encyclopedia of Genes and Genomes (KEGG pathway.The pathologic evaluation revealed one benign (benign non-teratoid, n=1 and six malignant tumors (malignant teratoid, n=2; malignant non-teratoid, n = 4. A total of 88 miRNAs were upregulated and 43 miRNAs were downregulated significantly (P<0.05 in the tumor specimens. Many of these significantly dysregulated miRNAs were known to play various roles in carcinogenesis and tumor behavior. RT-PCR validated three significantly upregulated miRNAs and three significantly downregulated miRNAs namely miR-217, miR-216a, miR-216b, miR-146a, miR-509-3p and miR-211. Many DE miRNAs that were significant in ME tumors showed dysregulation in retinoblastoma, glioblastoma, and precursor, normal and reactive human cartilage. Enriched pathway analysis suggested a significant association of upregulated miRNAs with 15 pathways involved in prion disease and several types of cancer. The pathways involving significantly downregulated miRNAs included the toll-like receptor (TLR (p<4.36E-16 and Nuclear Factor kappa B (NF-κB signaling pathways (p<9.00E-06.We report significantly dysregulated miRNAs in intraocular ME tumors, which exhibited abnormal profiles in other cancers as well such as retinoblastoma and glioblastoma. Pathway analysis

  2. Lente intra-ocular multifocal difrativa apodizada: resultados Diffractive apodized multifocal intraocular lens: results

    Directory of Open Access Journals (Sweden)

    Virgilio Centurion

    2007-12-01

    Full Text Available OBJETIVO: Mostrar os resultados visuais e refracionais com lente intra-ocular multifocal difrativa apodizada. MÉTODOS: Estudo de 100 olhos de 50 pacientes com catarata, submetidos à facoemulsificação com implante bilateral de lente intra-ocular (LIO multifocal difrativa apodizada. Foi avaliada a acuidade visual binocular sem e com correção para longe e perto, a previsibilidade refracional e a freqüência de uso de óculos. RESULTADOS: A acuidade visual sem correção para longe foi de e " 20/30 em 97,56% dos olhos operados e e" J2 em 100%, sendo que 82% dos pacientes nunca usam óculos e 16% usam de forma esporádica. CONCLUSÃO: A LIO multifocal difrativa apodizada mostrou ser uma opção previsível, reproduzível e segura na correção dos vícios de refração para longe e perto durante a cirurgia da catarata, permitindo elevado índice de independência ao uso de óculos.OBJECTIVE: To show visual and refraction results using multifocal diffractive apodized intraocular lens. METHODS: The study of 100 eyes of 50 patients with cataract, submitted to phacoemulsification with bilateral implant of multifocal diffractive apodized intraocular lens (IOL. Binocular visual acuity was evaluated with and without correction for near and distance, and refraction previsibility and frequency of wearing glasses. RESULTS: Visual acuity without correction for distance was e" 20/30 in 97.56% of eyes operated on and e" J2 in 100%, of these 82% of patients never wear glasses and 16% wear glasses sporadically. CONCLUSION: Multifocal diffractive apodized IOL proved to be a foreseeable option, reproducible and safe in the correction of refraction errors for distance and near during cataract surgery, enabling a high rate of independence from the use of glasses.

  3. Scanning Miniature Microscopes without Lenses

    Science.gov (United States)

    Wang, Yu

    2009-01-01

    The figure schematically depicts some alternative designs of proposed compact, lightweight optoelectronic microscopes that would contain no lenses and would generate magnified video images of specimens. Microscopes of this type were described previously in Miniature Microscope Without Lenses (NPO - 20218), NASA Tech Briefs, Vol. 22, No. 8 (August 1998), page 43 and Reflective Variants of Miniature Microscope Without Lenses (NPO 20610), NASA Tech Briefs, Vol. 26, No. 9 (September 1999), page 6a. To recapitulate: In the design and construction of a microscope of this type, the focusing optics of a conventional microscope are replaced by a combination of a microchannel filter and a charge-coupled-device (CCD) image detector. Elimination of focusing optics reduces the size and weight of the instrument and eliminates the need for the time-consuming focusing operation. The microscopes described in the cited prior articles contained two-dimensional CCDs registered with two-dimensional arrays of microchannels and, as such, were designed to produce full two-dimensional images, without need for scanning. The microscopes of the present proposal would contain one-dimensional (line image) CCDs registered with linear arrays of microchannels. In the operation of such a microscope, one would scan a specimen along a line perpendicular to the array axis (in other words, one would scan in pushbroom fashion). One could then synthesize a full two-dimensional image of the specimen from the line-image data acquired at one-pixel increments of position along the scan. In one of the proposed microscopes, a beam of unpolarized light for illuminating the specimen would enter from the side. This light would be reflected down onto the specimen by a nonpolarizing beam splitter attached to the microchannels at their lower ends. A portion of the light incident on the specimen would be reflected upward, through the beam splitter and along the microchannels, to form an image on the CCD. If the

  4. Associated depression in pseudophakic patients with intraocular lens with and without chromophore

    Directory of Open Access Journals (Sweden)

    Mendoza-Mendieta ME

    2016-03-01

    Full Text Available María Elena Mendoza-Mendieta, Ana Aurora Lorenzo-Mejía Association to Prevent Blindness in Mexico (APEC, Hospital “Dr Luis Sánchez Bulnes”, Mexico City, Mexico Background: With aging, the crystalline lens turns yellowish, which increases the absorption of wavelengths in the blue electromagnetic spectrum, reducing their photoreception in the retina. Since these wavelengths are the main stimulus in the regulation of the circadian rhythm, progressive reduction in their transmission is associated with chronic sleep disturbances and depression in elderly patients. Cataract extraction improves circadian photoreception at any age. However, lenses that block blue waves have 27% to 38% less melatonin suppression than lenses that block only ultraviolet (UV rays. Purpose: To assess the depression symptoms in subjects who have had bilateral phacoemulsification and intraocular lens (IOL implants, one group with yellow chromophore IOLs and the other group with transparent IOLs were compared. Setting: Association to Prevent Blindness in Mexico (APEC, Hospital “Dr Luis Sánchez Bulnes”. Design: This was an observational, cross-sectional, and single-center study. Materials and methods: Twenty-six subjects between 60 and 80 years of age, with a history of bilateral phacoemulsification and placement of the same type of IOL in both eyes from 4 to 12 months prior to the study, who attended the follow-up visits and agreed to participate in this study, and provided signed informed consent were included in the study. They were asked to answer the short version of the 15-item Geriatric Depression Scale. Results: The average age of the study participants was 72.5±5.94 years. The group without chromophore included 46.1% (n=12 of the patients and the group with chromophore included 53.9% (n=14 of the patients (P=0.088. Conclusion: In the group of patients with IOLs that block the passage of blue light, the depression rate was 21.4%, a rate similar to that

  5. Comparison of Candida Albicans Adherence to Conventional Acrylic Denture Base Materials and Injection Molding Acrylic Materials

    Directory of Open Access Journals (Sweden)

    Masoomeh Aslanimehr

    2017-03-01

    Full Text Available Statement of the Problem: Candida species are believed to play an important role in initiation and progression of denture stomatitis. The type of the denture material also influences the adhesion of candida and development of stomatitis. Purpose: The aim of this study was comparing the adherence of candida albicans to the conventional and injection molding acrylic denture base materials. Materials and Method: Twenty injection molding and 20 conventional pressure pack acrylic discs (10×10×2 mm were prepared according to their manufacturer’s instructions. Immediately before the study, samples were placed in sterile water for 3 days to remove residual monomers. The samples were then sterilized using an ultraviolet light unit for 10 minutes. 1×108 Cfu/ml suspension of candida albicans ATCC-10231 was prepared from 48 h cultured organism on sabouraud dextrose agar plates incubated at 37oC. 100 μL of this suspension was placed on the surface of each disk. After being incubated at 37oC for 1 hour, the samples were washed with normal saline to remove non-adherent cells. Attached cells were counted using the colony count method after shaking at 3000 rmp for 20 seconds. Finally, each group was tested for 108 times and the data were statistically analyzed by t-test. Results: Quantitative analysis revealed that differences in colony count average of candida albicans adherence to conventional acrylic materials (8.3×103 comparing to injection molding acrylic resins (6×103 were statistically significant (p<0.001. Conclusion: Significant reduction of candida albicans adherence to the injection acrylic resin materials makes them valuable for patients with high risk of denture stomatitis.

  6. Comparison of Candida Albicans Adherence to Conventional Acrylic Denture Base Materials and Injection Molding Acrylic Materials

    Science.gov (United States)

    Aslanimehr, Masoomeh; Rezvani, Shirin; Mahmoudi, Ali; Moosavi, Najmeh

    2017-01-01

    Statement of the Problem: Candida species are believed to play an important role in initiation and progression of denture stomatitis. The type of the denture material also influences the adhesion of candida and development of stomatitis. Purpose: The aim of this study was comparing the adherence of candida albicans to the conventional and injection molding acrylic denture base materials. Materials and Method: Twenty injection molding and 20 conventional pressure pack acrylic discs (10×10×2 mm) were prepared according to their manufacturer’s instructions. Immediately before the study, samples were placed in sterile water for 3 days to remove residual monomers. The samples were then sterilized using an ultraviolet light unit for 10 minutes. 1×108 Cfu/ml suspension of candida albicans ATCC-10231 was prepared from 48 h cultured organism on sabouraud dextrose agar plates incubated at 37oC. 100 μL of this suspension was placed on the surface of each disk. After being incubated at 37oC for 1 hour, the samples were washed with normal saline to remove non-adherent cells. Attached cells were counted using the colony count method after shaking at 3000 rmp for 20 seconds. Finally, each group was tested for 108 times and the data were statistically analyzed by t-test. Results: Quantitative analysis revealed that differences in colony count average of candida albicans adherence to conventional acrylic materials (8.3×103) comparing to injection molding acrylic resins (6×103) were statistically significant (pcandida albicans adherence to the injection acrylic resin materials makes them valuable for patients with high risk of denture stomatitis. PMID:28280761

  7. Intraocular pressure in Japanese diabetic patients

    Science.gov (United States)

    Matsuoka, Masato; Ogata, Nahoko; Matsuyama, Kayako; Yoshikawa, Tadanobu; Takahashi, Kanji

    2012-01-01

    Background To determine whether the intraocular pressure (IOP) in diabetic patients is significantly different from that in nondiabetic patients. Methods The medical records of all patients who were initially examined in the Department of Ophthalmology, Kansai Medical University, Takii Hospital were reviewed. At the initial examination, patients had a detailed interview and underwent a comprehensive ophthalmic examinations. All patients were over 20 years of age and did not have glaucoma. Results A total of 703 patients were evaluated. The mean (±standard error) IOP of the diabetic patients was 15.5 ± 0.2 mmHg (n = 206), and was significantly higher than the 14.0 ± 0.1 mmHg (n = 497) in the nondiabetic patients (P control of diabetes. PMID:22815643

  8. Primary orbital neuroblastoma with intraocular extension

    Directory of Open Access Journals (Sweden)

    Muthukrishnan Vallinayagam

    2015-01-01

    Full Text Available Neuroblastoma is an undifferentiated malignancy of primitive neuroblasts. Neuroblastoma is among the most common solid tumors of childhood. Orbital neuroblastoma is typically a metastatic tumor. In this case report, we describe a 2-year-old child with a rapidly progressing orbital tumor. Computed tomography revealed an orbital mass lesion with extraocular and intraocular components. An incisional biopsy was done, and a histopathological examination showed features suggestive of neuroblastoma. Systemic workup including ultrasonography of the abdomen, chest roentgenogram, whole body computed tomography, and bone scintigraphy showed no evidence of systemic involvement. The diagnosis of primary orbital neuroblastoma was made, and the child was subjected to chemotherapy followed by rapid melting of the tumor. Neuroblastoma should be considered in the differential diagnosis of childhood orbital tumors.

  9. Biological performance of functionalized biomedical polymers for potential applications as intraocular lens.

    Science.gov (United States)

    Zheng, Zhiwen; Wang, Yingjun; Jiao, Yan; Zhai, Zhichen

    2016-08-01

    To study the biological performance of surface-modified biomedical polymer materials, a model of the functional mechanism of nonspecific adsorption resistance was constructed. Cell behavior on the surface and in vivo transplantation features of intraocular lens (IOL) materials, such as hydrophobic acrylic ester and polymethyl methacrylate (PMMA), were investigated. The results of cell adhesion and proliferation studies showed that the addition of hirudin can significantly resist epithelial cell adhesion, better than the pure amination process, and thereby inhibit excessive proliferation on the surface. Experiments on the eyes of rabbits indicated that the IOL surfaces with hirudin modification reduced the incidence of cell aggregation and inflammation. Combined with a study of protein-resistant layer construction with recombinant hirudin on the material surface, the mechanism of surface functionalization was determined. The biological performance indicated that nonspecific adsorption is greatly decreased due to the existence of amphiphilic ions or hydration layers, which lead to stability and long-term resistance to nonspecific adsorption. These results offer a theoretical basis for the use of traditional biomedical polymer materials in long-term clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1961-1967, 2016.

  10. Investigations of Galaxy Clusters Using Gravitational Lensing

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Matthew P. [Northern Illinois Univ., DeKalb, IL (United States)

    2014-08-01

    In this dissertation, we discuss the properties of galaxy clusters that have been determined using strong and weak gravitational lensing. A galaxy cluster is a collection of galaxies that are bound together by the force of gravity, while gravitational lensing is the bending of light by gravity. Strong lensing is the formation of arcs or rings of light surrounding clusters and weak lensing is a change in the apparent shapes of many galaxies. In this work we examine the properties of several samples of galaxy clusters using gravitational lensing. In Chapter 1 we introduce astrophysical theory of galaxy clusters and gravitational lensing. In Chapter 2 we examine evidence from our data that galaxy clusters are more concentrated than cosmology would predict. In Chapter 3 we investigate whether our assumptions about the number of galaxies in our clusters was valid by examining new data. In Chapter 4 we describe a determination of a relationship between mass and number of galaxies in a cluster at higher redshift than has been found before. In Chapter 5 we describe a model of the mass distribution in one of the ten lensing systems discovered by our group at Fermilab. Finally in Chapter 6 we summarize our conclusions.

  11. Intraocular pressure in Japanese diabetic patients

    Directory of Open Access Journals (Sweden)

    Matsuoka M

    2012-07-01

    Full Text Available Masato Matsuoka,1 Nahoko Ogata,2 Kayako Matsuyama,1 Tadanobu Yoshikawa,1 Kanji Takahashi31Department of Ophthalmology, Kansai Medical University, Takii Hospital, Osaka, 2Department of Ophthalmology, Nara Medical University, Nara, 3Department of Ophthalmology, Kansai Medical University, Hirakata Hospital, Osaka, JapanBackground: To determine whether the intraocular pressure (IOP in diabetic patients is significantly different from that in nondiabetic patients.Methods: The medical records of all patients who were initially examined in the Department of Ophthalmology, Kansai Medical University, Takii Hospital were reviewed. At the initial examination, patients had a detailed interview and underwent a comprehensive ophthalmic examinations. All patients were over 20 years of age and did not have glaucoma.Results: A total of 703 patients were evaluated. The mean (±standard error IOP of the diabetic patients was 15.5 ± 0.2 mmHg (n = 206, and was significantly higher than the 14.0 ± 0.1 mmHg (n = 497 in the nondiabetic patients (P < 0.0001. The IOP was negatively correlated with age (r = –0.202; P = 0.024 in the diabetic patients and was weakly but significantly correlated with the glycosylated hemoglobin (HbA1c level (r = 0.240; P = 0.015 in the group with diabetic retinopathy.Conclusion: The significantly higher IOP in diabetic patients and positive correlation of IOP with HbA1c levels in patients with diabetic retinopathy indicate that IOP in diabetic patients is higher, especially in those with poor control of diabetes.Keywords: diabetes mellitus, diabetic retinopathy, intraocular pressure, open-angle glaucoma

  12. Tailoring strong lensing cosmographic observations

    Science.gov (United States)

    Linder, Eric V.

    2015-04-01

    Strong lensing time delay cosmography has excellent complementarity with other dark energy probes and will soon have abundant systems detected. We investigate two issues in the imaging and spectroscopic follow-up required to obtain the time delay distance. The first is optimization of spectroscopic resources. We develop a code to optimize the cosmological leverage under the constraint of constant spectroscopic time and find that sculpting the lens system redshift distribution can deliver a 40% improvement in dark energy figure of merit. The second is the role of systematics, correlated between different quantities of a given system or model errors common to all systems. We show how the levels of different systematics affect the cosmological parameter estimation and derive guidance for the fraction of double image vs quad image systems to follow as a function of differing systematics between them.

  13. Braneworld Black Hole Gravitational Lensing

    Science.gov (United States)

    Liang, Jun

    2017-04-01

    A class of braneworld black holes, which I called as Bronnikov-Melnikov-Dehen (BMD) black holes, are studied as gravitational lenses. I obtain the deflection angle in the strong deflection limit, and further calculate the angular positions and magnifications of relativistic images as well as the time delay between different relativistic images. I also compare the results with those obtained for Schwarzschild and two braneworld black holes, i.e., the tidal Reissner-Nordström (R-N) and the Casadio-Fabbri-Mazzacurati (CFM) black holes. Supported by Natural Science Foundation of Education Department of Shannxi Provincial Government under Grant No. 15JK1077, and Doctorial Scientific Research Starting Fund of Shannxi University of Science and Technology under Grant No. BJ12-02

  14. Artificial saliva effect on toxic substances release from acrylic resins

    Directory of Open Access Journals (Sweden)

    Kostić Milena

    2015-01-01

    Full Text Available Background/Aim. Acrylic-based resins are intensively used in dentistry practice as restorative or denture-base materials. The purpose of this study was to analyze the surface structure of denture base resins and the amount of released potentially toxic substances (PTS immediately upon polymerization and incubation in different types of artificial saliva. Methods. Storage of acrylic samples in two models of artificial saliva were performed in a water bath at the temperature of 37 ± 1°C. Analysis of the surface structure of samples was carried out using scanning electronic microscopy analysis immediately after polymerization and after the 30-day incubation. The amounts of PTS per day, week and month extracts were measured using high-pressure liquid chromatography. Results. Surface design and amount of PTS in acrylic materials were different and depended on the types and duration of polymerization. The surfaces of tested acrylates became flatter after immersing in solutions of artificial saliva. The degree of acrylic materials release was not dependent on the applied model of artificial saliva. Conclusion. In order to improve biological features of acrylic resin materials, it was recommended that dentures lined with soft or hard coldpolymerized acrylates should be kept at least 1 to 7 days in water before being given to a patient. So, as to reach high degree of biocompatibility preparation of prosthetic restorations from heat-polymerized acrylate was unnecessary. [Projekat Ministarstva nauke Republike Srbije, br. 41017

  15. 21 CFR 177.1310 - Ethylene-acrylic acid copolymers.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: POLYMERS Substances for Use as... this section are not applicable to ethylene-acrylic acid copolymers used in food-packaging adhesives... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene-acrylic acid copolymers. 177.1310...

  16. 40 CFR 721.8082 - Polyester polyurethane acrylate.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polyester polyurethane acrylate. 721... Substances § 721.8082 Polyester polyurethane acrylate. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as polyester polyurethane...

  17. Adjustable fluidic lenses for ophthalmic corrections.

    Science.gov (United States)

    Marks, Randall; Mathine, David L; Peyman, Gholam; Schwiegerling, Jim; Peyghambarian, Nasser

    2009-02-15

    We report on two fluidic lenses that have been developed for ophthalmic applications. The lenses use a circular aperture to demonstrate optical powers between -20 and +20 D and a rectangular aperture to demonstrate astigmatism with values ranging from 0 to 8 D. Measurements of image quality were made with the fluidic lens using a model eye. Both lenses were variable and controllable by adjusting the fluid volume of the lens. To the best of our knowledge this is the first demonstration of a continuously variable lens for control of astigmatism.

  18. Tevatron Electron Lenses: Design and Operation

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, Vladimir; /Fermilab; Bishofberger, Kip; /Los Alamos; Kamerdzhiev, Vsevolod; /Fermilab; Kozub, Sergei; /Serpukhov, IHEP; Kufer, Matthew; Kuznetsov, Gennady; Martinez, Alexander; Olson, Marvin; Pfeffer, Howard; Saewert, Greg; Scarpine, Vic; /Fermilab /SLAC /Fermilab /Serpukhov, IHEP /Novosibirsk, IYF /Serpukhov, IHEP /Fermilab

    2008-08-01

    The beam-beam effects have been the dominating sources of beam loss and lifetime limitations in the Tevatron proton-antiproton collider [1]. Electron lenses were originally proposed for compensation of electromagnetic long-range and head-on beam-beam interactions of proton and antiproton beams [2]. Results of successful employment of two electron lenses built and installed in the Tevatron are reported in [3,4,5]. In this paper we present design features of the Tevatron electron lenses (TELs), discuss the generation of electron beams, describe different modes of operation and outline the technical parameters of various subsystems.

  19. Lensing convergence in galaxy redshift surveys

    CERN Document Server

    Cardona, Wilmar; Kunz, Martin; Montanari, Francesco

    2016-01-01

    In this letter we demonstrate the importance of including the lensing contribution in galaxy clustering analyses with large galaxy redshift surveys. It is well known that radial cross-correlations between different redshift bins of galaxy surveys are dominated by lensing. But we show here that also neglecting lensing in the auto-correlations within one bin severely biases cosmological parameter estimation with redshift surveys. It leads to significant shifts for several cosmological parameters, most notably the scalar amplitude, the scalar spectral index and in particular the neutrino mass scale. Especially the latter parameter is one of the main targets of future galaxy surveys.

  20. Nanofocusing refractive X-ray lenses

    Energy Technology Data Exchange (ETDEWEB)

    Boye, Pit

    2010-02-05

    This thesis is concerned with the optimization and development of the production of nanofocusing refractive X-ray lenses. These optics made of either silicon or diamond are well-suited for high resolution X-ray microscopy. The goal of this work is the design of a reproducible manufacturing process which allows the production of silicon lenses with high precision, high quality and high piece number. Furthermore a process for the production of diamond lenses is to be developed and established. In this work, the theoretical basics of X-rays and their interaction with matter are described. Especially, aspects of synchrotron radiation are emphasized. Important in X-ray microscopy are the different optics. The details, advantages and disadvantages, in particular those of refractive lenses are given. To achieve small X-ray beams well beyond the 100 nm range a small focal length is required. This is achieved in refractive lenses by moving to a compact lens design where several single lenses are stacked behind each other. The, so-called nanofocusing refractive lenses (NFLs) have a parabolic cylindrical shape with lateral structure sizes in the micrometer range. NFLs are produced by using micro-machining techniques. These micro-fabrication processes and technologies are introduced. The results of the optimization and the final fabrication process for silicon lenses are presented. Subsequently, two experiments that are exemplary for the use of NFLs, are introduced. The rst one employs a high-resolution scanning fluorescence mapping of a geological sample, and the second one is a coherent x-ray diffraction imaging (CXDI) experiment. CXDI is able to reconstruct the illuminated object from recorded coherent diffraction patterns. In a scanning mode, referred to as ptychography, this method is even able to reconstruct the illumination and the object simultaneously. Especially the reconstructed illumination and the possibility of computed propagation of the wave field along the

  1. Twin axial vortices generated by Fibonacci lenses.

    Science.gov (United States)

    Calatayud, Arnau; Ferrando, Vicente; Remón, Laura; Furlan, Walter D; Monsoriu, Juan A

    2013-04-22

    Optical vortex beams, generated by Diffractive Optical Elements (DOEs), are capable of creating optical traps and other multi-functional micromanipulators for very specific tasks in the microscopic scale. Using the Fibonacci sequence, we have discovered a new family of DOEs that inherently behave as bifocal vortex lenses, and where the ratio of the two focal distances approaches the golden mean. The disctintive optical properties of these Fibonacci vortex lenses are experimentally demonstrated. We believe that the versatility and potential scalability of these lenses may allow for new applications in micro and nanophotonics.

  2. Visual Performance after Bilateral Implantation of a Four-Haptic Diffractive Toric Multifocal Intraocular Lens in High Myopes

    Science.gov (United States)

    Chan, Vincent K. C.

    2016-01-01

    Background. The vision with diffractive toric multifocal intraocular lenses after cataract surgery in long eyes has not been studied previously. Objectives. To report visual performance after bilateral implantation of a diffractive toric multifocal intraocular lens in high myopes. Methods. Prospective, observational case series to include patients with axial length of ≥26 mm and corneal astigmatism of >1 dioptre who underwent bilateral AT LISA 909M implantation. Postoperative examinations included photopic and mesopic distance, intermediate, and near visual acuity; photopic contrast sensitivity; visual symptoms (0–5); satisfaction (1–5); and spectacle independence rate. Results. Twenty-eight eyes (14 patients) were included. Postoperatively, mean photopic monocular uncorrected distance, intermediate, and near visual acuities (logMAR) were 0.12 ± 0.20 (standard deviation), 0.24 ± 0.16, and 0.29 ± 0.21, respectively. Corresponding binocular values were −0.01 ± 0.14, 0.13 ± 0.12, and 0.20 ± 0.19, respectively. One eye (4%) had one-line loss in vision. Under mesopic condition, intermediate vision and near vision decreased significantly (all P ≤ 0.001). Contrast sensitivity at all spatial frequencies did not improve significantly under binocular condition (all P > 0.05). Median scores for halos, night glare, starbursts, and satisfaction were 0.50, 0.00, 0.00, and 4.25, respectively. Ten patients (71%) reported complete spectacle independence. Conclusions. Bilateral implantation of the intraocular lens in high myopes appeared to be safe and achieved good visual performance and high satisfaction. PMID:27563460

  3. Visual Performance after Bilateral Implantation of a Four-Haptic Diffractive Toric Multifocal Intraocular Lens in High Myopes.

    Science.gov (United States)

    Chang, John S M; Chan, Vincent K C; Ng, Jack C M; Law, Antony K P

    2016-01-01

    Background. The vision with diffractive toric multifocal intraocular lenses after cataract surgery in long eyes has not been studied previously. Objectives. To report visual performance after bilateral implantation of a diffractive toric multifocal intraocular lens in high myopes. Methods. Prospective, observational case series to include patients with axial length of ≥26 mm and corneal astigmatism of >1 dioptre who underwent bilateral AT LISA 909M implantation. Postoperative examinations included photopic and mesopic distance, intermediate, and near visual acuity; photopic contrast sensitivity; visual symptoms (0-5); satisfaction (1-5); and spectacle independence rate. Results. Twenty-eight eyes (14 patients) were included. Postoperatively, mean photopic monocular uncorrected distance, intermediate, and near visual acuities (logMAR) were 0.12 ± 0.20 (standard deviation), 0.24 ± 0.16, and 0.29 ± 0.21, respectively. Corresponding binocular values were -0.01 ± 0.14, 0.13 ± 0.12, and 0.20 ± 0.19, respectively. One eye (4%) had one-line loss in vision. Under mesopic condition, intermediate vision and near vision decreased significantly (all P ≤ 0.001). Contrast sensitivity at all spatial frequencies did not improve significantly under binocular condition (all P > 0.05). Median scores for halos, night glare, starbursts, and satisfaction were 0.50, 0.00, 0.00, and 4.25, respectively. Ten patients (71%) reported complete spectacle independence. Conclusions. Bilateral implantation of the intraocular lens in high myopes appeared to be safe and achieved good visual performance and high satisfaction.

  4. Occupational fingertip eczema from acrylates in a manicurist

    Directory of Open Access Journals (Sweden)

    Denitza Zheleva

    2015-04-01

    Full Text Available Occupational hand eczema due to acrylates present in the workplace is a disease frequently reported among dentists, printers, and fiberglass workers. Acrylate monomers are used in the production of a great variety of polymers, including nail cosmetics. Our case report demonstrates a rare clinical presentations of allergic contact dermatitis from acrylic nails. Our patient was working as a manicurist and the diagnostic analyses revealed sensitation to some of the (meth acrylate compounds of her new nail cosmetics. Sculptured artificial acrylic and UV-hardened nails s are widely used in developed countries and they are gaining more and more popularity. We expect an increase in the number of cases of contact allergic dermatitis among manicurists and customers.

  5. Associated depression in pseudophakic patients with intraocular lens with and without chromophore

    Science.gov (United States)

    Mendoza-Mendieta, María Elena; Lorenzo-Mejía, Ana Aurora

    2016-01-01

    Background With aging, the crystalline lens turns yellowish, which increases the absorption of wavelengths in the blue electromagnetic spectrum, reducing their photoreception in the retina. Since these wavelengths are the main stimulus in the regulation of the circadian rhythm, progressive reduction in their transmission is associated with chronic sleep disturbances and depression in elderly patients. Cataract extraction improves circadian photoreception at any age. However, lenses that block blue waves have 27% to 38% less melatonin suppression than lenses that block only ultraviolet (UV) rays. Purpose To assess the depression symptoms in subjects who have had bilateral phacoemul-sification and intraocular lens (IOL) implants, one group with yellow chromophore IOLs and the other group with transparent IOLs were compared. Setting Association to Prevent Blindness in Mexico (APEC), Hospital “Dr Luis Sánchez Bulnes”. Design This was an observational, cross-sectional, and single-center study. Materials and methods Twenty-six subjects between 60 and 80 years of age, with a history of bilateral phacoemulsification and placement of the same type of IOL in both eyes from 4 to 12 months prior to the study, who attended the follow-up visits and agreed to participate in this study, and provided signed informed consent were included in the study. They were asked to answer the short version of the 15-item Geriatric Depression Scale. Results The average age of the study participants was 72.5±5.94 years. The group without chromophore included 46.1% (n=12) of the patients and the group with chromophore included 53.9% (n=14) of the patients (P=0.088). Conclusion In the group of patients with IOLs that block the passage of blue light, the depression rate was 21.4%, a rate similar to that observed in the elderly population, whereas no patients in the group with transparent IOLs had depression. PMID:27099465

  6. Antibiotic-loaded acrylic cement: current concepts.

    Science.gov (United States)

    Buchholz, H W; Elson, R A; Heinert, K

    1984-11-01

    Antibiotic-loaded acrylic cement has been used routinely since 1972 at the authors' hospitals, where a series of some 22,000 joint arthroplasty operations was performed from 1964-1983. The current status of the material is presented with up-to-date follow-up statistics on prophylactic therapy and on established deep infections. The results of 869 exchange arthroplasties are compared with results published in 1981. In the future, results will be presented in the form of survival curves. The method by which survival tables and curves are constructed is critical. Investigators should use survival curves for ease of comparison and because of the wide range of possibilities in an analysis of covariable factors. A retrospective actuarial analysis was made of 825 one-stage reimplantations in which antibiotic-loaded acrylic cement was used for infected total hip arthroplasties. Staphylococcus aureus was the most commonly encountered organism. Failure rates of prostheses infected by S. aureus, S. species, and anaerobic corynebacteria did not differ statistically. A factor that significantly contributed to failure of this method of treatment was Pseudomonas infection. By actuarial analysis five years after operation, a success (survival) rate of 77% was calculated.

  7. Application of Foldable Intraocular Lens in Multiple Types of Cataract

    Institute of Scientific and Technical Information of China (English)

    Songtao Yuan; Qinghuai Liu; Qing Jiang; Nanrong Yuan

    2002-01-01

    Objective: To evaluate the clinical results of implantation of foldable intraocular lens inmultiple types of cataract.Methods: This retrospective study comprised 162 eyes of 148 patients undergoingphacoemulsification and implantation of foldable intraocular lens, some of whom under-went combined pars plana vitrectomy or trabeculectomy or silicone oil removal. Theperiod of follow-up was from 3 months to 17 months.Results: There is slight reaction postoperatively in all cases. The postoperative uncorrectedvisual acuites was from 0. 05 to 1.2, patient with 0.6 or above acuity were 70.98%. Aneodymium: YAG capsulotomy was required in 5 eyes. Posterior capsule ruptured in 1eyes, and a PMMA intraocular lens was implanted in ciliary sulcus. In one eye, a lenswas removed because of recurrence of retina detachment.Conclusions: The application of foldable intraocular lens in multiple types of cataract issafe, and there is a slight postoperative reaction. less complications , and fast visualacuity recovery.

  8. Patient acceptability of the Tecnis® multifocal intraocular lens

    Directory of Open Access Journals (Sweden)

    Sood P

    2011-03-01

    Full Text Available Priyanka Sood1, Maria A Woodward21Emory Eye Center, Atlanta, GA, USA; 2Kellogg Eye Center, Ann Arbor, MI, USAAbstract: Cataract surgery has evolved. The goal of the surgeon includes both restoration of vision and refinement of vision. Patients' desire for spectacle independence has driven the market for presbyopia-correcting cataract surgery and development of novel intraocular lens (IOL designs. The Tecnis® Multifocal Intraocular Lens incorporates an aspheric, modified anterior prolate IOL with a diffractive multifocal lens design. The design aims to minimize spherical aberration and improve range of focus. The purpose of this review is to assess patient acceptability of the Tecnis® multifocal intraocular lens.Keywords: Tecnis®, intraocular lens, multifocal, presbyopia 

  9. [Intraocular lens implantation in developmental lens disorders in children].

    Science.gov (United States)

    Kanigowska, Krystyna; Grałek, Mirosława; Kepa, Beata; Chipczyńska, Barbara

    2009-01-01

    The pediatric cataract surgery in eyes with developmental disorders, stay with still considerable challenge. At children, the lasting vision development extorts necessity quick settlement of refraction defect formed after operation. The intraocular lens old boy with cataract in microspherophakia and 12 years old boy with cataract in lens with coloboma. One-piece flexible and rigid PMMA intraocular lens was placed with success at posterior chamber without scleral fixations and without using capsular tension ring in this cases. After 3 years of observation there were no decentration or dislocation of intraocular lens in both children. Authors concluded that in some cases posterior chamber intraocular lens implantation despite defective zonular or capsular support, can make up the effective method of surgical treatment without risk of early dislocation.

  10. Investigation of the relationship between intraocular pressure and ...

    African Journals Online (AJOL)

    Investigation of the relationship between intraocular pressure and total body water. ... Journal of Health and Visual Sciences ... attending Abia State University Optometry Clinic, Uturu, 100 healthy subjects of either sex were enlisted into study, ...

  11. Allergic contact dermatitis from acrylic nails in a flamenco guitarist.

    Science.gov (United States)

    Alcántara-Nicolás, F A; Pastor-Nieto, M A; Sánchez-Herreros, C; Pérez-Mesonero, R; Melgar-Molero, V; Ballano, A; De-Eusebio, E

    2016-12-01

    Acrylates are molecules that are well known for their strong sensitizing properties. Historically, many beauticians and individuals using store-bought artificial nail products have developed allergic contact dermatitis from acrylates. More recently, the use of acrylic nails among flamenco guitarists to strengthen their nails has become very popular. A 40-year-old non-atopic male patient working as a flamenco guitarist developed dystrophy, onycholysis and paronychia involving the first four nails of his right hand. The lesions were confined to the fingers where acrylic materials were used in order to strengthen his nails to play the guitar. He noticed improvement whenever he stopped using these materials and intense itching and worsening when he began reusing them. Patch tests were performed and positive results obtained with 2-hydroxyethyl methacrylate (2-HEMA), 2-hydroxyethyl acrylate (2-HEA), ethyleneglycol-dimethacrylate (EGDMA) and 2-hydroxypropyl methacrylate (2-HPMA). The patient was diagnosed with occupational allergic contact dermatitis likely caused by acrylic nails. Artificial nails can contain many kinds of acrylic monomers but most cases of contact dermatitis are induced by 2-HEMA, 2-HPMA and EGDMA. This is the first reported case of occupational allergic contact dermatitis from acrylates in artificial nails in a professional flamenco guitar player. Since the practice of self-applying acrylic nail products is becoming very popular within flamenco musicians, we believe that dermatology and occupational medicine specialists should be made aware of the potentially increasing risk of sensitization from acrylates in this setting. © The Author 2016. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Biocompatibility of acrylic resin after being soaked in sodium hypochlorite

    Directory of Open Access Journals (Sweden)

    Nike Hendrijatini

    2009-06-01

    Full Text Available Background: Acrylic resin as basic material for denture will stay on oral mucosa for a very long time. The polymerization of acrylic resin can be performed by conventional method and microwave, both produce different residual monomer at different toxicity. Acrylic resin can absorb solution, porous and possibly absorb disinfectantt as well, that may have toxic reaction with the tissue. Sodium Hypochlorite as removable denture disinfectant can be expected to be biocompatible to human body. The problem is how biocompatible acrylic resin which has been processed by conventional method and microwave method after being soaked in sodium hypochlorite solution. Purpose: The aim of this study was to understand in vitro biocompatibility of acrylic resin which has polimerated by conventional method and microwave after being soaked in sodium hypochlorite using tissue culture. Methods: Four groups of acrylic resin plate were produced, the first group was acrylic resin plate with microwave polymeration and soaked in sodium hypochlorite, the second group was acrylic resin plate with microwave polymeration but not soaked, the thirdwas one with conventional method and soaked and the last group was one with conventional method but not soaked, and in 1 control group. Each group consists of 7 plates. Biocompatibility test was performed in-vitro on each material using fibroblast tissue culture (BHK-21 cell-line. Result: The percentage between living cells and dead cells from materials which was given acrylic plate was wounted. The data was analyzed statistically with T test. Conclusion: The average value of living cells is higher in acrylic resin poimerization using microwave method compared to conventional method, in both soaked and non soaked (by sodium hypochlorite group. This means that sodium hypochlorite 0.5% was biocompatible to the mouth mucosa as removable denture disinfectant for 10 minutes soaking and washing afterwards.

  13. Anterior segment intraocular metallic foreign body causing chronic hypopyon uveitis

    OpenAIRE

    Mete, Güler; Turgut, Yılmaz; Osman, Arslanhan; Gülşen, Ülkü; Hakan, Artaş

    2010-01-01

    Intraocular foreign body (IOFB) is a common association of penetrating ocular trauma. Early diagnosis and removal of IOFBs especially if they are metallic is very important to determine further management and the final result of treatment. Missed IOFB may present in different clinical aspects that may limit its detection and symptoms may only become apparent after a prolonged period of time. We report a case of a missed metallic intraocular foreign body in the anterior chamber over a 2-year p...

  14. Patient acceptability of the Tecnis® multifocal intraocular lens

    OpenAIRE

    Woodward, Maria; Sood,Priyanka

    2011-01-01

    Priyanka Sood1, Maria A Woodward21Emory Eye Center, Atlanta, GA, USA; 2Kellogg Eye Center, Ann Arbor, MI, USAAbstract: Cataract surgery has evolved. The goal of the surgeon includes both restoration of vision and refinement of vision. Patients' desire for spectacle independence has driven the market for presbyopia-correcting cataract surgery and development of novel intraocular lens (IOL) designs. The Tecnis® Multifocal Intraocular Lens incorporates an aspheric, modified anter...

  15. [Treatment for penetrating wound caused by metallic intraocular foreign body].

    Science.gov (United States)

    Pienaru, M; Şerban, Ramona; Baltă, F

    2014-01-01

    Penetrating wounds with intraocular foreign body are ophthalmologic emergencies due to their severity and complexity and may require multiple surgeries for final resolution. 30-years-old patient with penetrating wound and metallic intraocular foreign body in the posterior vitreous requires successive operations for IOFB extraction, lensectomy, posterior vitrectomy for rhegmatogenous retinal detachment and then silicone oil extraction with final visual acuity 0, 4 PH.

  16. Intraocular nematode with diffuse unilateral subacute neuroretinitis: case report

    OpenAIRE

    Zakariah Sakinah; Said Mariyani; Alwi Azma-Azalina; Yusoff Munira,; Ghani Zulkifli; Zunaina Embong

    2011-01-01

    Abstract Background Live intraocular nematode is a rare occurrence. Nematode can migrate actively within the eye, creating visual symptoms and damaging ocular tissue. Case presentation A 26-year old man presented with painless reduced vision of the left eye for one week duration. It was associated with floaters. Visual acuity on the left eye was hand movement. Anterior segment examination was normal with normal intra-ocular pressure. Fundus examination showed a live nematode lying subretinall...

  17. Antifouling foldable acrylic IOLs loaded with norfloxacin by aqueous soaking and by supercritical carbon dioxide technology.

    Science.gov (United States)

    González-Chomón, Clara; Braga, Mara E M; de Sousa, Herminio C; Concheiro, Angel; Alvarez-Lorenzo, Carmen

    2012-10-01

    Cataracts treatment usually involves the extraction of the opaque crystalline lens and its replacement by an intraocular lens (IOL). A serious complication is the occurrence of endophthalmitis, a post-surgery infection mainly caused by Staphylococcus epidermidis, Staphylococcus aureus, and Pseudomonas aeruginosa. IOLs having the ability to load and to release norfloxacin in a controlled way and at efficient therapeutic levels may help to overcome these issues. In this work, acrylic hydrogels combining 2-hydroxyethyl methacrylate (HEMA) and 2-butoxyethyl methacrylate (BEM) at various ratios were prepared to attain biocompatible networks that can be foldable even in the dry state and thus insertable through minor ocular incision, and that load therapeutic amounts of norfloxacin. Acrylamide (AAm) and methacrylic acid (MAAc) were also incorporated as functional comonomers in small proportions. Water sorption, contact angle, protein adsorption, and optical properties of the networks were characterized. BEM notably decreased the T(g) of the networks, but also the loading by immersion in aqueous solution (presoaking). Then, a scCO(2)-based impregnation/deposition (SSI) method was implemented to improve the uptake of the drug. Loading capacities were discussed in terms of the comonomers composition and the employed method and operational conditions. The networks prepared with HEMA/BEM 20:80 vol/vol and processed with supercritical fluids combine adequate mechanical properties, biocompatibility and norfloxacin loading/release, and seem to be suitable for developing norfloxacin-eluting IOLs. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Relation between intraocular pressure and size of transverse sinuses

    Energy Technology Data Exchange (ETDEWEB)

    Kantarci, Mecit; Onbas, Omer; Alper, Fatih; Okur, Adnan [Atatuerk University, Department of Radiology, Medical Faculty, Erzurum (Turkey); Dane, Senol; Gumustekin, Kenan [Atatuerk University, Department of Physiology, Medical Faculty, Erzurum (Turkey); Aslankurt, Murat [Atatuerk University, Department of Ophtalmatology, Medical Faculty, Erzurum (Turkey); Yazici, Ahmet Taylan [Beyoglu Goez Egitim ve Arastirma Hastanesi, Istanbul (Turkey)

    2005-01-01

    There are asymmetries in the sizes of transverse sinus and intraocular pressure. The purpose of this study was to investigate possible relationships between the asymmetry of transverse sinuses in TOF MR venography and intraocular pressures of right and left eyes. In this study, subjects were 63 male and 42 female medical school students, aged 18-21 years (mean{+-}SD; 19.72{+-}0.67 years). Subjects with neurological and ophthalmologic disease, particularly dural sinus thrombosis, myopia, trauma and glaucoma, were excluded the study. Subjects were divided into five groups according to the magnitudes of the right- and left-transverse sinuses in MR venography results. There is a functional relation between intraocular pressures of the right and left eyes and asymmetry of the transverse sinus. If the transverse sinus on one side is larger and its venous drainage is greater, the intraocular pressure of the eye on this side is lower. It can be speculated that the transverse sinus size may be associated with pathogenesis of diseases with increased intraocular pressure such as glaucoma. We aim to determine the relation between the size and drainage of transverse sinuses in TOF MR venography and intraocular pressure in patients with open-angle glaucoma in our next study. (orig.)

  19. Dark Synergy Gravitational Lensing and the CMB

    CERN Document Server

    Hu, W

    2002-01-01

    Power spectra and cross-correlation measurements from the weak gravitational lensing of the cosmic microwave background (CMB) and the cosmic shearing of faint galaxies images will help shed light on quantities hidden from the CMB temperature anisotropies: the dark energy, the end of the dark ages, and the inflationary gravitational wave amplitude. Even with modest surveys, both types of lensing power spectra break CMB degeneracies and they can ultimately improve constraints on the dark energy equation of state w by over an order of magnitude. In its cross correlation with the integrated Sachs-Wolfe effect, CMB lensing offers a unique opportunity for a more direct detection of the dark energy and enables study of its clustering properties. By obtaining source redshifts and cross-correlations with CMB lensing, cosmic shear surveys provide tomographic handles on the evolution of clustering correspondingly better precision on the dark energy equation of state and density. Both can indirectly provide detections of...

  20. Weak Lensing Simulations for the SKA

    CERN Document Server

    Patel, Prina; Makhathini, Sphesihle; Abdalla, Filipe; Bacon, David; Brown, Michael L; Heywood, Ian; Jarvis, Matt; Smirnov, Oleg

    2015-01-01

    Weak gravitational lensing measurements are traditionally made at optical wavelengths where many highly resolved galaxy images are readily available. However, the Square Kilometre Array (SKA) holds great promise for this type of measurement at radio wavelengths owing to its greatly increased sensitivity and resolution over typical radio surveys. The key to successful weak lensing experiments is in measuring the shapes of detected sources to high accuracy. In this document we describe a simulation pipeline designed to simulate radio images of the quality required for weak lensing, and will be typical of SKA observations. We provide as input, images with realistic galaxy shapes which are then simulated to produce images as they would have been observed with a given radio interferometer. We exploit this pipeline to investigate various stages of a weak lensing experiment in order to better understand the effects that may impact shape measurement. We first show how the proposed SKA1-Mid array configurations perfor...

  1. Tear exchange and contact lenses: a review.

    Science.gov (United States)

    Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses.

  2. The Sloan Nearby Cluster Weak Lensing Survey

    CERN Document Server

    Kubo, Jeffrey M; Hardin, Frances Mei; Kubik, Donna; Lawhorn, Kelsey; Lin, Huan; Nicklaus, Liana; Nelson, Dylan; Reis, Ribamar R R; Seo, Hee-Jong; Soares-Santos, Marcelle; Stebbins, Albert; Yunker, Tony

    2009-01-01

    We describe and present initial results of a weak lensing survey of nearby ($\\rm{z}\\lesssim0.1$) galaxy clusters in the Sloan Digital Sky Survey (SDSS). In this first study, galaxy clusters are selected from the SDSS spectroscopic galaxy cluster catalogs of \\citet{miller05} and \\citet{berlind06}. We report a total of seven individual low redshift cluster weak lensing measurements which include: A2048, A1767, A2244, A1066, A2199, and two clusters specifically identified with the C4 algorithm. Our program of weak lensing of nearby galaxy clusters in the SDSS will eventually reach $\\sim 200$ clusters, making it the largest weak lensing survey of individual galaxy clusters to date.

  3. Electron Lenses for particle collimation in LHC

    CERN Document Server

    Shiltsev, V

    2008-01-01

    Electron Lenses built and installed in Tevatron have proven themselves as safe and very reliable instruments which can be effectively used in hadron collider operation for a number of applications, including compensation of beam-beam effects , DC beam removal from abort gaps , as a diagnostic tool. In this presentation we – following original proposal – consider in more detail a possibility of using electron lenses with hollow electron beam for ion and proton collimation in LHC.

  4. Coatings and Tints of Spectacle Lenses

    OpenAIRE

    H. Zeki Büyükyıldız

    2012-01-01

    Spectacle lenses are made of mineral or organic (plastic) materials. Various coatings and tints are applied to the spectacle lenses according to the characteristic of the lens material, and for the personal needs and cosmetic purpose. The coatings may be classified in seven groups: 1) Anti-reflection coatings, 2) Hard coatings, 3) Clean coat, 4) Mirror coatings, 5) Color tint coating (one of coloring processes), 6) Photochromic coating (one of photochromic processes), and 7) Anti-fog...

  5. Simulating HST observations of strong lensing clusters

    Science.gov (United States)

    Meneghetti, Massimo

    2014-10-01

    The Frontier Fields {FF} are using galaxy cluster gravitational lensing to boost the powers of Hubble and Spitzer to reveal the faintest galaxies yet observed. Accurate gravitational lensing models with uncertainty estimates are required to study some of the physical parameters of the lensed galaxies. Simulated HST observations of lensing clusters with known mass distributions are ideal to determine the accuracies of these modeling methods. Our team has begun performing these tests, demonstrating that integrated quantities such as lensed number counts are accurately recovered, enabling luminosity functions to be constrained. We have also begun to quantify magnification uncertainties for individual galaxies, but additional tests are needed. Here we propose to create a set of simulated osbervations of clusters selected to be analogs of the CLASH and FF clusters. They will include lensing effects and they will be delivered to the Mikulski Archive for Space Telescopes as a legacy product for others to analyze. They will be usable to extend our tests for robustly determine the accuracies in model magnification and mass measurements. Mass uncertainties will be a key ingredient in efforts to use galaxy clusters to constrain cosmology and theories of structure formation. Results from this program will also be useful to improve lens modeling methods toward more optimal use of the large numbers of lensing constraints available in deep FF imaging. This program will help astronomers realize the full potential of the large investments of Hubble, Spitzer, Chandra, and ground-based observing time in the FF, CLASH, and other past and future cluster lensing observations.

  6. Constraining Source Redshift Distributions with Gravitational Lensing

    CERN Document Server

    Wittman, D

    2012-01-01

    We introduce a new method for constraining the redshift distribution of a set of galaxies, using weak gravitational lensing shear. Instead of using observed shears and redshifts to constrain cosmological parameters, we ask how well the shears around clusters can constrain the redshifts, assuming fixed cosmological parameters. This provides a check on photometric redshifts, independent of source spectral energy distribution properties and therefore free of confounding factors such as misidentification of spectral breaks. We find that ~40 massive ($\\sigma_v=1200$ km/s) cluster lenses are sufficient to determine the fraction of sources in each of six coarse redshift bins to ~11%, given weak (20%) priors on the masses of the highest-redshift lenses, tight (5%) priors on the masses of the lowest-redshift lenses, and only modest (20-50%) priors on calibration and evolution effects. Additional massive lenses drive down uncertainties as $N_{lens}^0.5$, but the improvement slows as one is forced to use lenses further ...

  7. Cosmological test using strong gravitational lensing systems

    CERN Document Server

    Yuan, C C

    2015-01-01

    As one of the probes of universe, strong gravitational lensing systems allow us to compare different cosmological models and constrain vital cosmological parameters. This purpose can be reached from the dynamic and geometry properties of strong gravitational lensing systems, for instance, time-delay $\\Delta\\tau$ of images, the velocity dispersion $\\sigma$ of the lensing galaxies and the combination of these two effects, $\\Delta\\tau/\\sigma^2$. In this paper, in order to carry out one-on-one comparisons between $\\Lambda$CDM universe and $R_h=ct$ universe, we use a sample containing 36 strong lensing systems with the measurement of velocity dispersion from the SLACS and LSD survey. Concerning the time-delay effect, 12 two-image lensing systems with $\\Delta\\tau$ are also used. In addition, Monte Carlo (MC) simulations are used to compare the efficiency of the three methods as mentioned above. From simulations, we estimate the number of lenses required to rule out one model at the $99.7\\%$ confidence level. Compar...

  8. Hyperbranched Acrylated Aromatic Polyester Used as a Modifier in UV-Curable Epoxy Acrylate Resins

    Institute of Scientific and Technical Information of China (English)

    KOU,Hui-Guang; ASIF,Anila; SHI,Wen-Fang

    2003-01-01

    The viscosity, the shrinkage degree and the photoplymerization rate of the epoxy acrylate (EB600 ) blended with hyperbranched acrylated aromatic polyester ( HAAPE ) were investigated. The addition of HAAPE into EB600 largely reduces the viscosity of the blend formulation and the shrinkage degree. For example, EB600resin with 50% weight fraction of HAAPE has the 1250 cps of the viscosity and 2.0% of shrinkage degree, while the pure EB600 resin has 3000 cps of the viscosity and 10.5% of shrinkage degree. The photopolymerization rate of the rein is also promoted by HAAPE addition. The good miscibility between HAAPE and EB600 was also observed from the dynamic mechanical analysis. The tensile, flexural and compressive strength, and the thermal properties of the UVcured films are greatly improved.

  9. Equatorial potassium currents in lenses.

    Science.gov (United States)

    Wind, B E; Walsh, S; Patterson, J W

    1988-02-01

    Earlier work with the vibrating probe demonstrated the existence of outward potassium currents at the equator and inward sodium currents at the optical poles of the lens. By adding microelectrodes to the system, it is possible to relate steady currents (J) to the potential difference (PD) measured with a microelectrode. By injecting an outward current (I), it is possible to determine resistances and also the PD at which the steady outward potassium current becomes zero (PDJ = 0). At this PD the concentration gradient for potassium efflux and the electrical gradient for potassium influx are balanced so that there is no net flow of potassium across the membranes associated with the production of J. The PDJ = 0 for 18 rat lenses was 86 mV and that for 12 frogs lenses was -95 mV. This agrees with the potassium equilibrium potential and provides strong evidence to support the view that the outward equatorial current, J, is a potassium current. With the injection of outward current, I, the PD becomes more negative, the outward equatorial current, J, decreases, and the inward current at the optical poles increases. This suggests that there are separate electrical loops for K+ and Na+ that are partially linked by the Na, K-pump. Using Ohm's law, it is possible to calculate the input resistance (R = delta PD/I), the resistance related to the production of J (RJ = delta PD/delta J), and the effect of the combined resistances (delta J/I). The driving force for J can be estimated (PDJ = 0-PD). The relationships among currents, voltages and resistance can be used to determine the characteristics of the membranes that are associated with the outward potassium current observed at the equator. The effects of graded deformation of the lens were determined. The effects were reversible. The sites of inward and outward currents were not altered. Following deformation, the equatorial current, J, increased, and the PD became less negative. The PDJ = 0 remains the same so the ratio of K

  10. Poly(lauryl acrylate) and poly(stearyl acrylate) grafted multiwalled carbon nanotubes for polypropylene composites

    DEFF Research Database (Denmark)

    Daugaard, Anders Egede; Jankova Atanasova, Katja; Hvilsted, Søren

    2014-01-01

    in loading after 12 h of polymerization. The modified nanomaterials were melt mixed into polypropylene composites with very low filler loading (0.3 wt%), whereafter both the thermal and electrical properties were investigated by DSC and dielectric resonance spectroscopy. The electrical properties were found...... to be substantially improved, where poly(lauryl acrylate) was found to be the superior surface modification, resulting in a conductive composite....

  11. Use of Acrylic Acid Sodium Acrylate Polymer to Maintain Cocoa Seed Viability

    Directory of Open Access Journals (Sweden)

    Pudji Rahardjo

    2010-08-01

    Full Text Available The main problem of cocoa seed storage is moisture content of the seeds because cocoa seeds will germinate if cocoa seeds moisture content is high. The objective of this research is to maintain the cocoa seeds viability in storage using acrylic acid sodium acrylate polymer (AASAP. The function of AASAP is to absorb humidity in storage due to their ability to retain water and to prevent water loss. The experiment was conducted in a laboratory of Indonesian Coffee and Cocoa Research Institute and in Kaliwining Experimental Garden. This experiment was arranged by factorial randomized complete design, in wich AASAP dosages 0%; 0.1% (0.1 g/100 seeds; 0.2% (0.2 g/100 seeds, 0.3% (0.3 g/100 seeds, 0,4% (0,4g/100 seeds, combined with seeds storage period 1, 2, 3 and 4 weeks. The experiment used 3 replications and each repli cation used 100 seeds. Parameter of observation consisted of percentage of seeds germinated in storage, percentage of seeds infected by fungi in storage, seeds moisture content, percentage of seeds germination after storage, and early growth of cocoa seedlings. The results of the experiment showed that AASAP application with some dosages cocoa seeds storage cause to germinate in storage during 2 weeks. AASAP application with some dosages in cocoa seeds storage for 2 weeks would not result in infection by fungi and did not significantly affect seed germination after storage for 1, 2 and 4 weeks, and percentage of germination of cocoa seed after storage for 3 weeks decreased with increase dosage of AASAP. Higher dosage of AASAP would reduce early growth of cocoa seedling. Key words : Theobroma cacao, seed, acrylic acid sodium acrylate, seed storage, viabilty.

  12. COMPARATIVE ANALYSIS OF WATER SORPTION BY DIFFERENT ACRYLIC MATERIALS

    Directory of Open Access Journals (Sweden)

    Milena Kostić

    2014-06-01

    Full Text Available Acrylic materials are used daily for the production of mobile dental restorations and orthodontic appliances. The presence of residual monomer, as a product of incomplete polymerisation of material, results in more porous structure of the material, which greatly reduces the mechanical and physical quality of the acrylic restorations and increases the absorption of liquids. The aim of this study was to examine the water absorption of different types of resin material. In the study it was assumed that the cold polymerized acrylates show a greater potential for absorbing fluid from the environment in relation to the hot polymerized acrylic. The study included two hot and two cold polymerized acrylates, and cold polymerized acrylate impregnated with aesthetic pearls. In order to determine the degree of water absorption, the mass of the samples was measured before and after one day, seven days and thirty days of immersion in a water bath of body temperature. The tested hot and cold polymerized acrylates after immersion in water bath showed standard values of water absorption. The degree of water absorption was not significantly influenced by the type and manner of polymerisation. Water absorption values were significantly higher after seven days and thirty days of water storage relative to the observational period of one day.

  13. Clinical Application of Aspheric Intraocular Lens%浅谈非球面人工晶状体的临床应用

    Institute of Scientific and Technical Information of China (English)

    许玉梅

    2016-01-01

    目的:通过非球面人工晶状体植入术后视功能的变化,观察治疗效果,提出治疗建议,客观评价非球面人工晶状体的临床作用。方法从眼球面像差的特性,非球面人工晶状体的设计及矫正目标,非球面人工晶状体临床应用注意事项,非球面人工晶状体的视觉质量评价等方面进行分析。结果虽然非球面人工晶状体眼术后的高阶像差低于球面人工晶状体,但其视力和对比敏感度的结果并不完全与之相对应。由于目前我们对人眼波前像差的认识还不够深入,检测仪器不够完善,各阶像差与视功能之间的关系尚需进一步的研究。结论正常瞳孔下非球面人工晶状体眼与球面人工晶状体眼相比,非球面人工晶体可以有效减少球面像差,提高部分空间频率的对比敏感度,使患者拥有更好地视觉质量,但其不能体现减少术眼后高阶像差的优势。%Objective Through the changes of visual function after implantation of aspheric intraocular lens(IOL)observed treatment effect,treatment recommendations,and objective evaluation of non spherical intraocular lens(IOL)clinical effect. MethodsFrom the ocular wavefront aberration characteristics,the design of aspheric intraocular lens and correctional goal and clinical application of aspheric intraocular lenses note,aspheric intraocular lens visual quality evaluation were analyzed.Results Although the high order aberrations of the patients with non spherical intraocular lens were lower than that of the spherical intraocular lens,the visual acuity and contrast sensitivity were not completely corresponding with the results. Because at present we of wavefront aberration of understanding is not deep enough,detection equipment is not perfect,aberration and depending on the relationship between function stil need to further study.Conclusion With normal pupil non compared to spherical intraocular lens eyes and spherical

  14. Autorefraction versus subjective refraction in a radially asymmetric multifocal intraocular lens.

    Science.gov (United States)

    van der Linden, Jan Willem; Vrijman, Violette; Al-Saady, Rana; El-Saady, Rana; van der Meulen, Ivanka J; Mourits, Maarten P; Lapid-Gortzak, Ruth

    2014-12-01

    To evaluate whether the automated refraction (AR) correlates with subjective manifest (MR) refraction in eyes implanted with radially asymmetric multifocal intraocular lens (IOLs). This retrospective study evaluated 52 eyes (52 patients) implanted with a radially asymmetric multifocal IOL (LS-312 MF30, Oculentis, Germany). At 3 months postoperatively, the AR and MR values were compared to determine the correlation between the sphere (S), the spherical equivalent (SE) and the astigmatic components J0 and J45. The difference of mean spherical measurement was +0.98D ± 0.62, with the AR measuring more myopic. The difference of the mean spherical equivalent was +1.11D ± 0.57, again with AR being more myopic. Both these differences were statistically significant (p refractive parameters showed r(2) = 0.067, r(2) = 0.078, r(2) = 0.018 and r(2) = 0.015, respectively, all of which point to a low correlation between the AR and the MR. Autorefraction shows poor correlation to manifest subjective refraction with these radially asymmetric multifocal IOLs. The autorefraction systematically underestimates the spherical and spherical equivalent power, while the correlation between the astigmatic components was also low. Autorefraction seems not a valid starting point for manifest subjective refraction with these types of lenses, unless a corrective factor of about +1 dioptre is used. © 2014 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

  15. Visual outcomes and optical quality after implantation of a diffractive multifocal toric intraocular lens

    Science.gov (United States)

    Chen, Xiangfei; Zhao, Ming; Shi, Yuhua; Yang, Liping; Lu, Yan; Huang, Zhenping

    2016-01-01

    Background: This study evaluated the visual function after implantation of a multifocal toric intraocular lenses (IOLs). Materials and Methods: This study involved 10 eyes from eight cataract patients with corneal astigmatism of 1.0 diopter (D) or higher who had received phacoemulsification with implantation of an AcrySof IQ ReSTOR Toric IOL. Six-month evaluations included visual acuity, spherical equivalent (SE), defocus curve, residual astigmatism, IOL rotation, contrast sensitivity (CS), wavefront aberrations, modulation transfer function (MTF), and patient satisfaction assessments. Results: At 6 months postoperatively, uncorrected distance visual acuity (logarithm of the minimum angle of resolution) was 0.09 ± 0.04, corrected distance visual acuity was 0.02 ± 0.11, and uncorrected near visual acuity was 0.12 ± 0.07. The mean SE was −0.095 ± 0.394 D (±0.50 D in 90%). Refractive astigmatism at the 6-month follow-up visit was significantly reduced to 0.35 ± 0.32 D from 1.50 ± 0.41 D presurgery (P 0.05). There was an increase in MTF results between preoperative and postoperative evaluations at all spatial frequencies. Conclusions: The diffractive multifocal toric IOL is able to provide a predictable astigmatic correction with apparently outstanding levels of optical quality after implantation. PMID:27221680

  16. Ultrasound Biomicroscopy Comparison of Ab Interno and Ab Externo Intraocular Lens Scleral Fixation

    Science.gov (United States)

    Horiguchi, Lie; Garcia, Patricia Novita; Malavazzi, Gustavo Ricci; Allemann, Norma

    2016-01-01

    Purpose. To compare ab interno and ab externo scleral fixation of posterior chamber intraocular lenses (PCIOL) using ultrasound biomicroscopy (UBM). Methods. Randomized patients underwent ab externo or ab interno scleral fixation of a PCIOL. Ultrasound biomicroscopy was performed 3 to 6 months postoperatively, to determine PCIOL centration, IOL distance to the iris at 12, 3, 6, and 9 hours, and haptics placement in relation to the ciliary sulcus. Results. Fifteen patients were enrolled in the study. The ab externo technique was used in 7 eyes (46.6%) and the ab interno in 8 eyes (53.3%). In the ab externo technique, 14 haptics were located: 4 (28.57%) in the ciliary sulcus; 2 (14.28%) anterior to the sulcus; and 8 (57.14%) posterior to the sulcus, 6 in the ciliary body and 2 posterior to the ciliary body. In the ab interno group, 4 haptics (25.0%) were in the ciliary sulcus, 2 (12.50%) anterior to the sulcus, and 10 (75.0%) posterior to the sulcus, 4 in the ciliary body and 6 posterior to the ciliary body. Conclusions. Ab externo and ab interno scleral fixation techniques presented similar results in haptic placement. Ab externo technique presented higher vertical tilt when compared to the ab interno. PMID:27293878

  17. Ultrasound Biomicroscopy Comparison of Ab Interno and Ab Externo Intraocular Lens Scleral Fixation.

    Science.gov (United States)

    Horiguchi, Lie; Garcia, Patricia Novita; Malavazzi, Gustavo Ricci; Allemann, Norma; Gomes, Rachel L R

    2016-01-01

    Purpose. To compare ab interno and ab externo scleral fixation of posterior chamber intraocular lenses (PCIOL) using ultrasound biomicroscopy (UBM). Methods. Randomized patients underwent ab externo or ab interno scleral fixation of a PCIOL. Ultrasound biomicroscopy was performed 3 to 6 months postoperatively, to determine PCIOL centration, IOL distance to the iris at 12, 3, 6, and 9 hours, and haptics placement in relation to the ciliary sulcus. Results. Fifteen patients were enrolled in the study. The ab externo technique was used in 7 eyes (46.6%) and the ab interno in 8 eyes (53.3%). In the ab externo technique, 14 haptics were located: 4 (28.57%) in the ciliary sulcus; 2 (14.28%) anterior to the sulcus; and 8 (57.14%) posterior to the sulcus, 6 in the ciliary body and 2 posterior to the ciliary body. In the ab interno group, 4 haptics (25.0%) were in the ciliary sulcus, 2 (12.50%) anterior to the sulcus, and 10 (75.0%) posterior to the sulcus, 4 in the ciliary body and 6 posterior to the ciliary body. Conclusions. Ab externo and ab interno scleral fixation techniques presented similar results in haptic placement. Ab externo technique presented higher vertical tilt when compared to the ab interno.

  18. Ultrasound Biomicroscopy Comparison of Ab Interno and Ab Externo Intraocular Lens Scleral Fixation

    Directory of Open Access Journals (Sweden)

    Lie Horiguchi

    2016-01-01

    Full Text Available Purpose. To compare ab interno and ab externo scleral fixation of posterior chamber intraocular lenses (PCIOL using ultrasound biomicroscopy (UBM. Methods. Randomized patients underwent ab externo or ab interno scleral fixation of a PCIOL. Ultrasound biomicroscopy was performed 3 to 6 months postoperatively, to determine PCIOL centration, IOL distance to the iris at 12, 3, 6, and 9 hours, and haptics placement in relation to the ciliary sulcus. Results. Fifteen patients were enrolled in the study. The ab externo technique was used in 7 eyes (46.6% and the ab interno in 8 eyes (53.3%. In the ab externo technique, 14 haptics were located: 4 (28.57% in the ciliary sulcus; 2 (14.28% anterior to the sulcus; and 8 (57.14% posterior to the sulcus, 6 in the ciliary body and 2 posterior to the ciliary body. In the ab interno group, 4 haptics (25.0% were in the ciliary sulcus, 2 (12.50% anterior to the sulcus, and 10 (75.0% posterior to the sulcus, 4 in the ciliary body and 6 posterior to the ciliary body. Conclusions. Ab externo and ab interno scleral fixation techniques presented similar results in haptic placement. Ab externo technique presented higher vertical tilt when compared to the ab interno.

  19. Avaliação da eficácia da facectomia com implante de lente intra-ocular na infância Efficacy of pediatric cataract extraction with intraocular lens implantation

    Directory of Open Access Journals (Sweden)

    Núbia Cristina de Freitas Maia

    2005-12-01

    Full Text Available OBJETIVO: Avaliar eficácia da utilização da lente intra-ocular na correção da afacia na infância, segundo a acuidade visual e alteração refracional no pós-operatório. MÉTODOS: Foram estudados trinta e três olhos de 27 crianças portadores de catarata, unilateral ou bilateral, submetidos à cirurgia de lensectomia via pars plana com implante de lente intra-ocular, associada à capsulectomia posterior primária e vitrectomia anterior. O cálculo da lente intra-ocular foi realizado com o objetivo da emetropia no pós-operatório imediato. As crianças apresentavam idades inferiores a seis anos no momento da cirurgia e foram acompanhadas em média durante 2,9 anos. Foram divididas em três grupos: crianças portadoras de catarata unilateral operadas com idade inferior a três anos (Grupo I e superior a três anos (Grupo II e grupo III formado pelas crianças portadoras de cataratas bilaterais. RESULTADOS: Acuidade visual pós-operatória obtida no último controle igual ou superior a 20/40 foi encontrada em 85% dos olhos operados. Equivalente esférico no primeiro mês pós-operatório próximo da emetropia foi obtido em 70% das crianças do grupo III e em apenas 30% do grupo I. Quanto à variação refracional pós-operatória, a miopização foi encontrada em 81,81% dos casos, sendo maior esta alteração refracional quanto menor a idade em que a criança foi submetida à cirurgia. CONCLUSÃO: Apesar da miopização pós-operatória que ocorre com o implante de lente intra-ocular na correção da afacia em crianças com menos de seis anos de idade, o resultado visual é bastante satisfatório e a correção refracional residual de fácil execução. Um seguimento pós-operatório mais prolongado há de ser necessário para o acompanhamento dos resultados a longo prazo.PURPOSE: To evaluate the efficacy of the use of intraocular lenses in the treatment of pediatric aphakia, according to postoperative visual acuity and refraction change

  20. Electrochemical characterization of aminated acrylic conducting polymer

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Norma Mohammad [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Heng, Lee Yook [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia); Ling, Tan Ling [Southeast Asia Disaster Prevention Research Initiative, Lestari Universiti Kebangsaan Malaysia (UKM), 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2015-09-25

    New attempt has been made to synthesize aminated acrylic conducting polymer (AACP) using precursor of phenylvinylsulfoxide (PVS). The process was conducted via the integration of microemulsion and photopolymerization techniques. It has been utilized for covalent immobilization of amino groups by the adding of N-achryiloxisuccinimide (NAS). Thermal eliminating of benzene sulfenic acids from PVS has been done at 250 °C to form electroactive polyacetylene (PA) segment. Characterization of AACP has been conducted using fourier transform infrared (FTIR), scanning electron microscopy (SEM) and linear sweep cyclic voltammetry (CV). A range of 0.3-1.25μm particle size obtained from SEM characterization. A quasi-reversible system performed as shown in electrochemical study.