DOCSLIB.ORG

Anterior Chamber Foldable Phakic Intra Ocular Lens Safety and Efficacy

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Anterior Chamber Foldable Phakic Intra Ocular Lens Safety and Efficacy Journal of Clinical Research and Ophthalmology eertechz AlAhmady Hamad AlSamman*, Ashraf Research Article Mostafa Moahammed and Usama Ali Mohammed Department of Ophthalmology, Faculty of Medicine, Anterior Chamber Foldable Phakic Sohag University, Egypt Dates: Received: 01 November, 2016; Accepted: Intra Ocular Lens Safety and Efficacy 09 November, 2016; Published: 15 November, 2016 *Corresponding author: Alahmady Hamad Abstract Alsmman, MD, Department of Ophthalmology, Purpose: Correction of myopia by implantation of intra ocular lens is a growing surgery. In this Faculty of Medicine, Sohag University, 82524, study I am trying to assess the visual outcome stability and safety of eyes undergoing Anterior chamber Sohag, Egypt, Tel: 0020-11 11 10 26 98 ; E-mail: foldable phakic lens implantation (Artiflex) (Ophtec BV, Groningen, The Netherlands) or (veriflex) (AMO,Santa Ana,CA) for myopia unsuitable for LASIK and detection of early and late complications www.peertechz.com along three years follow up period. ISSN: 2455-1414 Methods: A retrospective analysis of 25 eyes of 16 patients underwent Anterior chamber foldable phakic IOL (Artiflex) or (Veriflex) implantation for correction of myopia all patients were unsuitable Keywords: Phakic IOL; Myopia; Refractive surgery for LASIK all patients underwent surgery with one surgeon in same circumstances. Uncorrected visual acuity, corrected visual acuity (BCVA), higher-order aberrations, patient satisfaction, central endothelial cell count, and PIOL position centration and incarcerated iris tissue were determined along follow up period. Results: At the end of the 36 months of follow up period 14 of the 25 eyes (56 %) achieved BCVA better than that measured pre-operatively and 10 of the 25 eyes (40%) matched their pre-operative BCVA. One eye (4 %) attained a final BCVA worse than pre-operatively, due to recurrent uveitis. One patient (4%) need another surgery to fixate the lens due to slippage of incarcerated iris tissue with impending displacement. Conclusions: This study suggests that Anterior chamber foldable phakic IOL (iris claw lens insertion) Artiflex or Veriflex is beneficial in myopia, unsuitable for LASIK, matching or exceeding pre- operative BCVA in the overwhelming majority of the cases. With no major complications however long standing follow up is needed to avoid major complications. Abbreviations As many patients with myopia unsuitable for LASIK the Intraocular refractive procedures may be a good alternative: high PIOL: Phakic Intra Ocular Lens; IOL: intraocular Lens; LASIK: degrees of ametropia thin corneas and keratoconus suspect can be Laser Insitu Keratomeleiosis; PRK: Photorefracive Keratectomy; corrected, more stable refraction, better visual quality in day and night BCVA: Best Corrected Visual Acuity; UCVA: Uncorrected Visual Acuity; PMMA: Poly Methel Metha Arylate; ACD: Anterior Chamber and lastly reversibility of our technique all of above make intraocular Depth; ECD: Endothelial Cell Count; SE: Spherical Equivilant refractive surgery is a good alternative in patients refusing glasses and contact lenses [7,8]. Introduction Intraocular refractive surgeries may be classified into: phakic Most of patients are hoping to see well without spectacle or intraocular lens (PIOL) implantation with preservation of crystalline contact lenses. So in last years the refractive surgery increased in lens and clear lens extraction with lens implantation, also called patients dissatisfied with spectacles and contact lenses either due to quality of vision, cosmetic appearance or difficulties in contact refractive lens exchange. Clear lens extraction may increases the risk lenses wearing and its complications. corneal surgeries like corneal for retinal detachment and is generally not preferable in myopic pre- ablation ( photorefractive keratectomy (PRK) and laser-assisted in presbyopic patients who can still accommodate as it deprive them situ keratomileusis LASIK) and different types of phakic intraocular from useful accommodation and always patient suffers from disability lens (PIOL) implantation either in the anterior or posterior chamber of near vision without glasses. Retinal detachment after refractive lens and the anterior chamber either iris claw or angle fixation IOL aim to exchange for high myopia is always present and has been described correct s refractive errors in myopic patients [1,2]. to occur in 2% to 8% of patients which increase if complications Corneal surgeries, such as photorefractive keratectomy (PRK) and occurred during surgery [9,10]. LASIK, have many limitations and contraindications especially for PIOL implantation in suitable patients may be more favorable than the correction of high refractive errors. Postoperative ectasia which other refractive surgery techniques, the PIOL is potentially reversible is a major problem can occur with removing of too much corneal as the PIOL is removable surgically with any major complication. tissue to correct high myopia with the laser. Night bad quality vision Visual recovery is fast, and accommodation is preserved with great and dry eye complaints may be transient or permanent symptoms which may cause dissatisfaction for refractive patients. Due to these benefit in pre presbyopic patients. Implantation of a PIOL utilizes limitations and complications, indications for corneal refractive operative techniques familiar to most anterior segment surgeons surgery have narrowed [3-6]. and does not require expensive or specialised devices, such as an Citation: AlSamman AH, Moahammed AM, Mohammed UA (2016) Anterior Chamber Foldable Phakic Intra Ocular Lens Safety and Efficacy. J Clin Res Ophthalmol 3(1): 034-040. DOI: 10.17352/2455-1414.000033 034 AlSamman, et al. (2016) excimer laser. On the other hand complications relating to PIOLs acuity (BSCVA),) refraction both manifest andand after complete can be more disabling than those from keratorefractive surgery. cycloplegia by cyclopentolate 1% 6 hours before examination and Glaucoma, cataract formation, corneal decompensation, uveitis, and the spherical equivalent (SE) were calculated, meticulus slit-lamp endophthalmitis are potential complications after PIOL insertion examination for the anterior segment , pupil size by manualcard [11]. comparison method was measured, corneal topography endothelial cell density (ECD), applanation tonomety by tonopen and fundus In the 1980s, as an increasing number of reports indicated examination by direct and indirect ophthalmoscopy for detection of complications from use of the angle-supported PIOLs, a new type of peripheral retinal abnormalities . UCVA and BSCVA were measured anterior-chamber PIOL was developed based on the 1977 design of in decimal Snellen and converted to the logarithm of the minimum Jan Worst’s iris-fixated “iris-claw” lens [12-14]. angle of resolution (logMAR). Corneal endothelium count was The name of the PIOL was changed to Artisan (Ophtec BV, evaluated by use of Topcon noncontact specular microscope. Groningen, The Netherlands), and it is available for myopic patients The calculation of the IOL power was done by using van der with powers from −3 to −23.5 D. In 2004, the PIOL gained FDA Heijde formula, which uses the corneal curvature, ACD, and manifest approval under the name Verisyse Phakic IOL (Abbott Medical SE of the refractive error at a vertex distance of 12 mm, the calculation Optics, Inc., Santa Ana, CA), with available powers from −5 to −20 was done in each cases by the manufacturing company. D. A toric Artisan model is also available in Europe with parameters similar to the Artisan, but with cylindrical powers up to -7.5D [15- Surgical technique 17]. Before the surgery by one hour, topical antibiotic Vigamox The Artiflex and Veriflex foldable IOLs are a three-piece lenses (moxifloxacin hydrochloride ophthalmic solution 0.5%) with were developed based on the Artisan design, with a flexible, 6.0-mm pilocarpine 2% (isoptocarpine) was installed in the conjunctival sac convex–concave silicone optic, PMMA haptics, and overall diameter of all eyes every 15 minutes 4 times the miotics installed in order of 8.5 mm. to ease lens fixation in the iris tissue and avoid pupil dilation after anaesthesia and protection of crystalline lens from touch during Myopic IOL is available in powers of −2 to −14.5 D, and it implantation. Surgeries were performed by same surgeon and under utilizes a small (3.2 mm), self-sealing incision, thereby allowing for same circumstances all surgeries were done under general anaesthesia more rapid recovery of visual acuity. The Artiflex has Conformité only 3mm clear corneal incision was performed at 12 o’clock Européene marking in the European Union and is undergoing FDA by keratome ,the anterior chamber reformation by viscoelastic clinical trials as the Veriflex lens (Abbott Medical Optics, Inc.) [18]. material (Healon GV, Abbott Medical Optics, Santa Ana, CA, USA) Aim of the work and two paracentesis were located at 10 o’clock and 2 o’clock. The PIOL was loaded on special spatula (Operaid Artiflex Implantation To assess the visual outcome stability and safety of eyes Spatula, Ophtec, Groningen, and the Netherlands) and introduced undergoing anterior chamber foldable phakic lens implantation into the anterior chamber through keratome opening the lens after (Artiflex and veriflex) for myopia unsuitable for LASIK and detection introduction it will be in vertical position from 12 to 6 o’clock there of early and late complications along three years follow up period. after rotated 90° into a horizontal
Load more

Recommended publications
  • Safety Considerations for Phakic Iols Avoid Potential Problems by Paying Attention to These Points
    REFRACTIVE SURGERY FEATURE STORY Safety Considerations for Phakic IOLs Avoid potential problems by paying attention to these points. BY GWyn SAMUEL WILLIAMS, MRCS; AND MOHAMMED MUHTASEB, FRCOPHTH n the decades since their introduction in the 1950s, phakic IOLs have become a compelling option for the correction of refractive error. There are, however, potential problems that can result from electing a Iphakic IOL as part of a refractive solution. Consequently, various safety parameters have been devised to mini- mize risks. But before complications can be properly addressed, it is important to distinguish among the avail- able phakic IOLs and differentiate those problems associ- ated with each lens design. TYPES OF PHAKIC IOL Initial phakic IOL designs were angle-fixated lenses Figure 1. The Artisan lens is the longest-serving example of intended for implantation in the anterior chamber.1 an iris-supported lens. Unfortunately, the first 5-year follow-up study demon- strated a high rate of angle recession, glaucoma, hyphe- Posterior chamber phakic IOLs. The move to the pos- ma, endothelial cell loss, and decentration, leading to terior chamber began in the 1980s, when surgeons began removal in up to 60% of cases.2 Subsequent lens designs fixating iris-supported lenses on the posterior rather than improved, and today, in addition to anterior chamber the anterior face of the iris but continued to place the phakic IOLs, posterior chamber phakic IOLs are also optic in the anterior chamber.6 These so-called anterior- available. posterior lenses were associated with pupil block and Anterior chamber phakic IOLs. Phakic IOLs designed daytime photophobia in bright light, as the pupil could for the anterior chamber are either angle-supported or not constrict beyond a certain size due to the protrud- iris-supported.
    [Show full text]
  • Artisan Iris-Fixated Toric Phakic and Aphakic Intraocular Lens Implantation for the Correction of Astigmatic Refractive Error After Radial Keratotomy
    CASE REPORT Artisan iris-fixated toric phakic and aphakic intraocular lens implantation for the correction of astigmatic refractive error after radial keratotomy Nayyirih G. Tahzib, MD, Fred A.G.J. Eggink, PhD, Monica T.P. Odenthal, MD, Rudy M.M.A. Nuijts, MD, PhD We report 2 patients who had radial keratotomy (RK) to correct myopia. The first patient developed a postoperative hyperopic shift and cataract. Nine years post RK, she had intracapsular cataract extraction and implantation of an Artisan aphakic intraocular lens (IOL). Twenty years post RK, hyperopia and astigmatism progressed to C7.0 À5.75 Â 100 with a best corrected visual acuity (BCVA) of 20/20. Due to contact lens intolerance, the Artisan aphakic IOL was exchanged for an Artisan toric aphakic IOL. Three months later, the BCVA was 20/20 with C1.0 À0.50 Â 130. The second patient demonstrated residual myopic astigmatism 6 years after bilateral RK and had be- come contact-lens intolerant. An Artisan toric phakic IOL was implanted in both eyes. Four months later, the BCVA was 20/25 with a refraction of C0.25 À1.0 Â 135 and 20/20 with a refraction of À1.0 Â 40. Both patients were satisfied with the visual outcomes. J Cataract Refract Surg 2007; 33:531–535 Q 2007 ASCRS and ESCRS Before the introduction of excimer laser technology, with a 5.0 mm optical zone. The aphakic model is radial keratotomy (RK) was the most commonly also available with a convex–convex optic configura- performed refractive surgical procedure to correct tion.
    [Show full text]
  • Friess, OD, FAAO
    2/15/18 Myopia, The Refrac5ve Market and Phakic IOLs in Modern Refrac5ve Surgery David W. Friess, OD, FAAO Head of Global Professional Affairs Staar Surgical Company President, OCCRS Optometric Cornea, Cataract and Refrac5ve Society Financial Interest Disclosures • STAAR Surgical Co. – Employee, Shareholder • Opmus Clinical Partners LLC – President/Owner 1 2/15/18 Phakic IOL Product Informaon • ATTENTION: Reference the Visian ICL™ and Verisyse™ Product Informaon for a complete lis5ng of indicaons, warnings and precau5ons. Refrac5ve Market Stas5cs • Includes US/Canada/Mexico LASIK, PRK/surface ablaon, phakic IOLs, and refrac5ve lens exchange • 2007 1M+ refrac5ve procedures • 2013 600,0001 • 2015 vision correc5on market in the US2: – Over 60% require vision correc5on (nearly 200M people) – Spectacles, contact lenses – Refrac5ve surgery penetraon remains at less than 3% – 600,000 refrac5ve procedures in 2015 • 2016 Q1 Market Scope: – 172,000 refrac5ve procedures 1. Cataract & Refrac5ve Surgery Today, July 2014 2. The Vision Council. heps://www.thevisioncouncil.org/topic/problems-condi5ons/adults 2 2/15/18 Refrac5ve Opportunity: Boomers vs. Millennials • US Census Bureau Es5mates1: – 75.4 million Baby Boomers in 2014. Ages 51 to 69 in 2015. – 74.8 million Millennials in 2014. Ages 18 to 34 in 2015. – By 2015, Millennials increased to 75.3 million and became the biggest group. 1. hep://www.pewresearch.org/fact-tank/2015/01/16/this-year-millennials-will-overtake-baby-boomers/ Myopia Research and Coverage in Mainstream Media • Huffington Post, 03/22/2016: Nearsightedness Has a Far-Reaching Impact As the Myopia Epidemic Spreads Around the Globe – References new research from the Brien Holden Vision Ins5tute (AUS) study on the prevalence of myopia • Holden BA, et al.
    [Show full text]
  • Phakic Intraocular Lenses Outcomes and Complications: Artisan Vs Visian
    Eye (2011) 25, 1365–1370 & 2011 Macmillan Publishers Limited All rights reserved 0950-222X/11 www.nature.com/eye 1,2 1,2 Phakic intraocular MA Hassaballa and TA Macky CLINICAL STUDY lenses outcomes and complications: Artisan vs Visian ICL Abstract procedures offer many potential advantages: a broader range of treatable ametropia, faster Purpose To evaluate the safety and visual visual recovery, more stable refraction, and outcomes of two phakic intraocular lenses better visual quality.4–6 Two basic intraocular (IOLs) for correction of high myopia: Artisan refractive procedures exist: phakic intraocular and Visian ICL (ICL). lens (pIOL) implantation, and clear lens Patients and methods In this retrospective extraction with lens implantation. Refractive study, a phakic IOL was implanted in 68 lens exchange may increase the risk for retinal highly myopic eyes of 34 patients; 42 eyes detachment,7 and is generally not considered in received an Artisan IOL, and 26 eyes received myopic pre-presbyopic patients who can still ICL IOL. accommodate. Results All patients completed a 1-year The risks and benefits of pIOL implantation follow-up. The mean preoperative spherical in appropriate patients may be more favorable equivalent (SEQ) was À12.89±3.78, and than other refractive surgery techniques. The À12.44±4.15 diopters (D) for Artisan and pIOL is removable surgically, with fast visual ICL (P ¼ 0.078), respectively. The mean recovery, and preserved accommodation. postoperative (1-year) uncorrected distance However, it is important to realize that visual acuity was 0.39±0.13 and 0.41±0.15 complications relating to pIOLs can be more logMAR for Artisan and ICL, respectively disabling than those from keratorefractive (P ¼ 0.268).
    [Show full text]
  • Results of Cataract Surgery After Implantation of an Iris-Fixated Phakic Intraocular Lens
    ARTICLE Results of cataract surgery after implantation of an iris-fixated phakic intraocular lens Niels E. de Vries, MD, Nayyirih G. Tahzib, MD, PhD, Camille J. Budo, MD, Carroll A.B. Webers, MD, PhD, Ruben de Boer, MD, Fred Hendrikse, MD, PhD, Rudy M.M.A. Nuijts, MD, PhD PURPOSE: To report the results of cataract surgery after previous implantation of an Artisan iris- fixated phakic intraocular lens (pIOL) for the correction of myopia. SETTING: University center and private practice. METHODS: This study comprised eyes with previous implantation of an iris-fixated pIOL to correct myopia and subsequent pIOL explantation combined with cataract surgery and in-the-bag implan- tation of a posterior chamber IOL. Predictability of refractive results, changes in endothelial cell density (ECD), and postoperative best corrected visual acuity (BCVA) were analyzed. RESULTS: The mean follow-up after cataract surgery in the 36 eyes of 27 consecutive patients was 5.7 months G 7.5 (SD). The mean time between pIOL implantation and cataract surgery was 5.0 G 3.4 years. After explantation of the pIOL and subsequent cataract surgery, the mean spherical equiv- alent (SE) was À0.28 G 1.11 diopters (D); the SE was within G1.00 D of the intended correction in 72.2% of patients and within G2.00 D in 86.1% of patients. The mean endothelial cell loss after the combined procedure was 3.5% G 13.2% and the mean postoperative BCVA, 0.17 G 0.18 logMAR. CONCLUSIONS: In patients with a history of implantation of an iris-claw pIOL for the correction of myopia, cataract surgery combined with explantation of the pIOL yielded acceptable predictability of the postoperative SE and minimal loss of ECD, resulting in a gain in BCVA.
    [Show full text]
  • Anterior Chamber Iris-Fixated Phakic Intraocular Lens for Anisometropic Amblyopia
    Anterior chamber iris-fixated phakic intraocular lens for anisometropic amblyopia Ruchi Saxena, MS, Helena M. van Minderhout, BO, Gregorius P.M. Luyten, MD, PhD We report a child who had implantation of an iris-fixated Artisan phakic intraocu- lar lens (IOL) to correct high unilateral myopia to support the therapy of anisome- tropic amblyopia. After IOL implantation, the patient continued occlusion therapy to further treat the amblyopic eye. One year postoperatively, the best corrected visual acuity in the amblyopic eye was 1.00 and binocular stereovision had devel- oped. The visual acuity remained stable through 3 years of follow-up. There were no complications, although postoperative endothelial cell loss was significant. J Cataract Refract Surg 2003; 29:835–838 © 2003 ASCRS and ESCRS igh unilateral myopia is difficult to treat in young postoperative inflammation, and a possible myopic shift Hchildren and often leads to anisometropic ambly- as the patient ages. opia.1–5 Factors such as the depth of the amblyopia and Artisan phakic IOL implantation is a reliable and the age of the patient play a key role in the effectiveness safe procedure in adults.8,9 Although the IOL is consid- of treatment. Success is also frequently hampered by ered experimental in several parts of the world, it has practical problems such as those created by glasses and been implanted in patients in The Netherlands since contact lenses. Thus far, however, patient compliance 1991. Thus, when we were confronted with a young has been considered the greatest therapeutic impedi- anisometropic amblyopic patient with restricted treat- ment.6,7 In such cases, refractive surgery with the exci- ment options, we decided to correct his high unilateral mer laser or phakic intraocular lens (IOL) implantation myopia using the Artisan phakic IOL.
    [Show full text]
  • Facts You Need to Know About Implantation of the Artisan Phakic
    ARTISAN® PHAKIC LOL FACTS YOU NEED TO KNOW ABOUT IMPLANTATION OF THE ARTISAN® PHAKIC TOL (-5 TO -20 D) FOR THE CORRECTION OF MYOPIA (Nearsightedness) PATIENT INFORMATION BROCHURE This brochure is designed to help you and your ophthalmologist decide whether or not to have surgery for imlplanftation of the ARTISAN® PHAKIC 10L. Please read this entire brochure. Discuss its contents thoroughly with your ophthalmologist so that you have all of your questions answered to your satisfaction. Ask any questions before you agree to the surgery. CAUTION: Federal Law restricts this device to sale by or on the order of a physician OP1HTEC USA, Inc. 6421 Congress Ave., Suite 11 2 Boca Raton, FL 33487 561-989-8767 http:// vw.0PHTEC.corn This booklet may he reproduced only by a physician considering treating a patient with the ARTISANTm Pliakic 101. lbr the treatment of myopia. All other rights reserved. Sept 1,00994 Pa,-,e I Table of Contents 1. Introduction ............................................................................................................. 3 2. How the Eye Functions ........................................................................................... 3 3. W hat is the ARTISAN® Phakic IOL? ..................................................................... 5 4. Are You a Good Candidate for the ARTISAN® Phakic IOL? ............................... 6 5. Benefits of the ARTISAN® Phakic IOL ................................................................. 6 6. Risks of the ARTISAN " IOL ................................................................................
    [Show full text]
  • Phakic Iols Outside the United States
    CATARACT SURGERY PHAKIC IOLS Phakic IOLs Outside the United States When do I implant these lenses? By John So Min Chang, MD Assuming adequate corneal tissue and a pupil that is not overly large, I seldom hear complaints about halo Phakic IOLs are becoming more popular in and glare when patients’ myopia is below -10.00 D, but Hong Kong due to the prevalence of high they are the chief grievances for higher corrections. In myopia among Hong Kong Chinese.1 Thirty Hong Kong, most people do not drive, so night vision is percent of my Chinese LASIK patients have a lesser concern. I therefore sometimes will correct as -8.00 D or more of myopia. When choosing much as -12.00 D of myopia in this population. For pa- between LASIK and phakic IOLs, I generally offer the latter tients from mainland China and other countries who if the patient has a manifest refraction spherical equivalent drive at night, however, I begin recommending a phakic of -10.00 D or higher. Currently, I am using the Visian ICL IOL rather than LASIK if their level of myopia exceeds (STAAR Surgical, Monrovia, CA) and the AcrySof Phakic -10.00 D. IOL (Alcon Laboratories, Inc., Fort Worth, TX; not available I tell all high myopes that studies have shown that the in the United States) for patients with less than 1.50 D of Visian ICL provides better vision than LASIK to eyes with astigmatism, which I can easily correct intraoperatively moderate and high myopia2,3 (Figure 1). If these patients with limbal relaxing incisions.
    [Show full text]
  • Phakic Intraocular Lens Implantation 2018
    Patient Information Phakic Intraocular Lens Implantation 1 Contents What is phakic intraocular lens (PIOL) implantation? 3 What are the benefits? 3 Who is suitable for PIOL implantation? 4 What are the alternatives? 4 Vision correction surgery alternatives 4 Alternative PIOLs 4 Continuing in glasses or contact lenses 4 How is PIOL implantation performed? 5 Loss of vision 5 Additional surgery 6 Risks of contact lens wear 6 What are the side effects? 6 Vision 6 Eye comfort 6 Eye appearance 6 Will PIOL implantation affect my future eye health care? 7 How can I reduce the risk of problems? 7 How much does PIOL implantation cost? 8 2 What is phakic intraocular lens (PIOL) implantation? Lenses that are implanted into the eye to correct vision without taking out the natural lens are call phakic intraocular lenses (PIOLs). PIOLs are made of clear synthetic plastic. They sit either just in front of, or just behind, the pupil – a bit like building your contact lenses into your eyes. PIOL implantation is effective in treating high The other main type of PIOL is the Artisan/Verysise spectacle prescriptions, and is widely used to treat PIOL. This PIOL clips onto the iris just in front of the younger patients who are not suitable for laser eye pupil, and is sometimes visible as a glint in the eye. surgery. Like ICLs, you cannot feel Artisan/Verysise PIOLs after implantation, and you do not need to clean them. The commonest type of PIOL implanted in the UK and worldwide is the Visian ICL (intraocular collamer If you are suitable for PIOL implantation, your lens).
    [Show full text]
  • Refractive Surgery
    Corporate Medical Policy Refractive Surgery File Name: refra ctive_surgery Origination: 4/1981 Last CAP Review: 6/2021 Next CAP Review: 6/2022 Last Review: 6/2021 Description of Procedure or Service The term refractive surgery describes various procedures that modify the refractive error of the eye. Refractive surgery involves surgery performed to reshape the cornea of the eye (refractive keratoplasty) or the way the eye focuses light internally. Vision occurs when light rays are bent or refracted by the cornea a nd lens and received by the retina, (the nerve layer at the back of the eye), in the form of an image, which is sent through the optic nerve to the brain. Refractive errors occur when the eye cannot properly focus light and images a ppear out of focus. The main types of refractive errors a re myopia (nearsightedness), hyperopia (farsightedness) and astigmatism (distortion). Presbyopia (aging eye) is a problem of the lens and is characterized by the inability to bring close objects into focus. Refractive errors are generally corrected with glasses or contact lenses. Refractive keratoplasty includes all surgical procedures on the cornea to improve vision by changing the shape, and thus the refractive index, of the corneal surface. Refractive keratoplasties can be broadly subdivided into keratotomies, i.e., corneal incisions; keratectomies, i.e., removal of corneal epithelium; a nd keratomileusis, i.e., resha ping a stromal layer of the cornea. Refractive keratoplasties include the following surgeries: Ra dial keratotomy (RK) is a surgica l procedure for nearsightedness. Using a high-powered microscope, the physician places micro-incisions (usually 8 or fewer) on the surface of the cornea in a pattern much like the spokes of a wheel.
    [Show full text]
  • Phakic Intraocular Lenses Part 2: Results and Complications
    REVIEW/UPDATE Phakic intraocular lenses Part 2: Results and complications Thomas Kohnen, MD, PhD, FEBO, Daniel Kook, MD, Merce Morral, MD, Jose Luis Guell,€ MD The second part of a review of phakic intraocular lenses (pIOLs) addresses results and complica- tions with current pIOL models. Phakic IOLs demonstrate reversibility, high optical quality, poten- tial gain in visual acuity in myopic patients due to retinal magnification; correction is not limited by corneal thickness or topography. With proper anatomical conditions, pIOLs also show good results in hyperopic patients. Toric pIOL designs enable spherocylindrical correction. Complica- tions are rare and primarily related to pIOL position and type. The main complications of angle- supported anterior chamber pIOLs are glare and halos, pupil ovalization, and corneal endothelial cell loss; of iris-fixated anterior chamber pIOLs, chronic subclinical inflammation, corneal endo- thelial cell loss, and dislocation or pupillary block glaucoma; and of posterior chamber pIOLs, anterior subcapsular cataract formation, pigment dispersion, and luxation or pupillary block glau- coma. No causative relationship between pIOL implantation (of any pIOL type) and retinal detach- ment has been established. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. J Cataract Refract Surg 2010; 36:2168–2194 Q 2010 ASCRS and ESCRS Implantation of intraocular lenses in the phakic eye been on the market for some time. This second part (pIOL) is a relatively new technique to correct high of the pIOL review reassesses the published data ametropia. Time between the introduction of new about results and complications of currently available pIOL designs is short; thus, experience with a new pIOLs.
    [Show full text]
  • The Verisyse™ Seminar
    Patient Seminar Welcome to the Verisyse™ Seminar Today we’ll answer some of the most common questions about the Verisyse™ Phakic Intraocular Lens (IOL) including: • Who is a candidate • How the procedure is performed • Advantages of this FDA-approved vision procedure Did you know? • An estimated 90 million people have nearsightedness so severe it cannot be corrected with Custom LASIK or other procedures. • Most non-LASIK candidates can overcome their vision limitations with the Verisyse™ procedure. • In independent studies, patients preferred Verisyse™ to LASIK for improved clarity of vision. What does Verisyse™ do? • Verisyse™ was designed to correct moderate to severe nearsightedness in patients who are not good candidates for Custom LASIK. • Verisyse™ is placed behind your cornea and works along side your natural crystalline lens. • Verisyse™ may offer high-quality, high- definition vision and freedom from glasses or contact lenses. What is a phakic intraocular lens (IOL)? • The Verisyse™ Phakic IOL is a micro lens placed behind your cornea. • It is made out of PMMA, the same material used safely for the past 50 years in cataract surgery. • “Phakic” means that your natural crystalline lens is left in the eye. – Your natural lens helps your eye adjust between seeing objects that are near and far An overview of the Verisyse™ Procedure An outpatient treatment, the procedure takes only about 15 to 30 minutes. One eye is treated at a time. 1. Eye drops will be given to reduce your pupil size. 2. For better access to your eye, your doctor will use an instrument to comfortably hold your eyelids open during the procedure.
    [Show full text]