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BOGOTA LASER REFRACTIVE INSTITUTE BOGOTA COLOMBIA SOUTHAMERICA. BASIC PRINCIPLES OF PRESBYOPIA. GUSTAVO E. TAMAYO MD. PRESBYOPIA DEFINITION. PRESBYOPIA IS LOSS OF ACCOMODATION INSIDE THE EYE Loss of “auto-focus” Difficult vision at near
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BOGOTA LASER REFRACTIVE INSTITUTE BOGOTA COLOMBIA SOUTHAMERICA BASIC PRINCIPLES OF PRESBYOPIA GUSTAVO E. TAMAYO MD
PRESBYOPIA DEFINITION • PRESBYOPIA IS LOSS OF ACCOMODATION INSIDE THE EYE • Loss of “auto-focus” • Difficult vision at near • Need to increase the distance between the objects and the eye • Distant vision remains unchanged.
Presbyopia • Progressive Age-related loss of accommodation • Begins early in life • Early 40s: Functional vision affected • Complete loss of accommodation by 5th to 6th decade • Most prevalent ocular affliction • 100% of population
Etiology of Presbyopia • Lenticular Changes • lenticular sclerosis • changes in capsular elasticity • change in zonular insertion angle • Extralenticular Changes • Neuromuscular changes • Ciliary muscle changes Glasser, A et al RSIG 1997
Near Distance Intermediate THE VISION WITH PRESBYOPIA
NORMAL YOUNG EYE • Lens makes the auto focus
SOME PRESBYOPIA FACTS • Presbyopia is the most common problem encountered today. All persons over 45 will suffer some form of Presbyopia • Myopia is the prevalent refractive defect when compared to hyperopia, making myopia with presbyopia a larger group for refractive surgery when compared to the group with hyperopia • Myopics seek for surgery more than hyperopics due to bad uncorrected visual acuity for distance. • Most common hyperopic defect is lower than 2 diopters and distant visual acuity is usually not as bad as in myopia. Therefore, hyperopics do not seek for surgery as myopic patient does.
SOME PRESBYOPIA FACTS • Mean age group for presbyopic patient is 45 years or more. This translates into a more independent group when monetary reasons become an issue for the surgery • Market for presbyopia surgery is therefore big, completely unexplored and it seems right to assume it will be the major source for eye surgery in the next years. • Eye products manufacturers are already very well aware of the problem and the market and have concentrated many resources to find a solution for this defect.
HOW TO TREAT PRESBYOPIA? • Lenses: a) two pairs: one for distance and one for near b) bifocals or progressive multifocal lenses • Contact lenses: a) correction for distance and addition of glasses for near b) Multifocal contact lenses • Surgery
SURGERY FOR PRESBYOPIA • CORNEA • SCLERA • ANTERIOR CHAMBER • LENS
SURGERY IN THE CORNEA CORNEAL INLAYS: a) Acufocus: ACI 7000 (Irvine, Cal) b) Presbylens (Revision Optics, Cal) c) FlexiVue (Presbia Corp. Amsterdam) • They are made of Biocompatible material inserted inside the cornea and alter the way light rays enter the eye (Like a Contact Lens)
SURGERY IN THE CORNEA CORNEAL INLAYS: • Still not approved by FDA and therefore not available in USA. All of them in Clinical FDA trials. • Several advantages: a) Extraocular surgery b) Reversible c) Exchangeable
SURGERY IN THE CORNEA EXCIMER LASER SURGERY: • Monovision: one eye (dominant) for distance and one eye (Non Dominant) for near Only approved Corneal surgery in USA by the FDA. Difficult to tolerate by most of the patients. Loss of Contrast and depth perception by the patients (not suitable for high demanding visual needs) Limited useful time.
SURGERY IN THE CORNEA EXCIMER LASER SURGERY: • Multifocal Cornea: Excimer Laser reshapes the cornea and alters the way light rays enter the eye. (Like Contact Lenses) Has been named as PRESBYLASIK. Both eyes see near and distance. Several softwares in use by some of the Lasers Manufacturers. Temporary solution for some years Repeatable and/or reversible
Frequently Asked Question • How Does this treatment work if the pupil gets smaller when reading? CREATION OF A PERIPHERAL KNEE
HOW THE TREATMENT WORKS WITH A SMALL PUPIL? POSTOPERATIVE PREOPERATIVE The knee
SURGERY IN THE CORNEA CONDUCTIVE KERATOPLASTY: • A probe touches the cornea with High Radiofrequency and by collagen shrinkage reshapes the cornea. • Produces controlled monovision inducing Myopia • Only suitable for Hyperopes • FDA approved as Monovision Blended Vision • Rapid loss of effect is the main problem • Its use has decreased in the last years.
SURGERY IN THE SCLERA SCLERAL EXPANSION PROCEDURE: • Small incisions in the sclera close to the cornea and insertion of a band to create an space for the ciliary muscle to move. • Ciliary muscle is the “autofocus” muscle • Defensors claim improve accomodation • Not FDA approved. Not in use in USA. • Its use has declined dramatically due to not consistent results.
SURGERY IN THE ANTERIOR CHAMBER PHAKIC MULTIFOCAL INTRAOCULAR LENSES: • Lenses inserted inside the eye over the iris (Verizyse-Artisan) or under the iris (Visian ICL) • The natural Lens is not removed • FDA approved for correction of Myopia not for Presbyopia • Still prototypes. • Main advantage is reversibility..
SURGERY IN THE LENS MULTIFOCAL INTRAOCULAR LENSES ACCOMODATIVE INTRAOCULAR LENSES • The natural lens is removed through surgery and replaced by one of those lenses. • FDA approved to be used for cataract surgery • Off Label used as clear lens exchange (PRELEX) • Very popular method internationally • Not very commonly used in USA • CristalensAccomodative is number one used in USA
SURGERY IN THE LENS MULTIFOCAL INTRAOCULAR LENSES ACCOMODATIVE INTRAOCULAR LENSES • Both types still under development and research. • Very strong visual symptoms have produced decrease of its use in “young” presbyopes. • Not reversible surgery • Decreased contrast sensitivity • They require a careful selection of candidates and lots of counseling.