Download Sin título de diapositiva

BOGOTA LASER REFRACTIVE INSTITUTE
BOGOTA COLOMBIA
SOUTHAMERICA
BASIC PRINCIPLES OF PRESBYOPIA
GUSTAVO E. TAMAYO MD
GT
PRESBYOPIA DEFINITION

PRESBYOPIA IS LOSS OF ACCOMODATION
INSIDE THE EYE
Loss of “auto-focus”
2. Difficult vision at near
3. Need to increase the distance between the
objects and the eye
4. Distant vision remains unchanged.
1.
GT
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
GT
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
GT
THE VISION WITH PRESBYOPIA
Distance
Intermediate
Near
GT
NORMAL YOUNG EYE

Lens makes the auto focus
GT
GT
GT
HOW TO TREAT PRESBYOPIA?

Glasses: a) two pairs: one for distance
and
one for near
b) bifocals or progressive multifocal
glasses
 Contact lenses: a) correction for distance and
addition of glasses for near
b) Multifocal contact lenses
 Surgery
GT
GT
SURGERY FOR PRESBYOPIA

CORNEA

SCLERA

ANTERIOR CHAMBER

LENS
GT
SURGERY IN THE CORNEA
CORNEAL INLAYS:
a) Acufocus: ACI 7000 (Irvine, Cal)
b) Presbylens (Revision Optics, Cal)
c) FlexiVue microlens (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)
GT
Corneal Inlays
Waring recently discussed results of the Kamra
smallaperture corneal inlay to improve near
vision in emmetropic presbyopes. The inlay is 5μm thick and 3.8 mm in total diameter, with a 1.6mm central aperture that increases depth of
focus and improves near visual acuity by
restricting bent light rays from entering the eye
similar to the f-stop in a camera.
GT
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
GT
Flexivue Microlens

The Flexivue Microlens, a corneal inlay
treatment for presbyopia, is 3-mm in diameter
and about 15 microns thick. The lens is placed
about 280-300 microns deep in the cornea of
the patient's non-dominant eye through a
pocket created using a femtosecond laser.[1]
The specific vision-correcting prescription for
each patient is incorporated in the outer area
of the lens.[2] The procedure lasts about 10
minutes, and after the lens insertion, the
pocket self-seals and holds the lens in place. GT
Acufocus
GT
Acufocus
GT
GT
Flexivue Microlens
GT
GT
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.
GT
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
GT
Frequently Asked Question

How Does this treatment work if the pupil gets
smaller when reading?
CREATION OF A PERIPHERAL KNEE
GT
Multifocal Cornea
GT
HOW THE TREATMENT WORKS
WITH A SMALL PUPIL?
PREOPERATIVE
POSTOPERATIVE
The knee
GT
Intracore Femtosecond Laser















Femtosecond Lasers
In a prospective, nonrandomized trial, Holzer et al
presented early outcomes of Intracor femtosecond laser
treatment for presbyopia. The investigators treated the
nondominant eye of 25 patients using the Technolas
Perfect Vision femtosecond laser (Technolas Perfect
Vision GmbH). The procedure involves the creation of
five consecutive intrastromal rings around the line of
sight. Treatment times were approximately 20 seconds.
The mean gain in UCVA was 4.42 lines, with a range of
0 to 9 lines of improvement. The mean loss of distance
BCVA was -0.46 ±0.83.9 Similarly, Ruiz et al evaluated
83 eyes of 45 patients with 6- to 12-month follow-up.
Of the 83 eyes, 89.2% achieved both J2 and 20/25 or
better, and 69.9% achieved a near UCVA of J1.
GT
Femtosecond Lasers
GT
Excimer Lasers and Multifocal
Corneal Ablations




It should be noted that,
although near vision is better, the quality of distance
vision
provided by these models is worse than that of a
presbyopic
emmetropic eye.6
GT
GT
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.
GT
CONDUCTIVE KERATOPLASTY
GT
CONDUCTIVE KERATOPLASTY
GT
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.
GT
SCLERAL EXPANSION
SURGERY
GT
Scleral Expansion Surgery
GT
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..
GT
PHAKIC LENS: VERISYSE
GT
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
Cristalens Accomodative is number one used in
USA
GT
Multifocal IOL
GT
Multifocal IOL
GT
ACCOMODATIVE CRISTALENS
GT
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.
GT
Capsular Bag Refilling










Hao et al recently introduced data on injectable in situ
curable accommodating IOLs. Using functionalized polysiloxane
macromonomers, they were able to refill the
empty lens capsular bag via an injection. To prevent leakage
from the capsular bag, the investigators performed
in situ cross-linking of polysiloxane gel using blue light
(wavelength, 400-500 nm) at an intensity of 70 mW/cm2.
A 3-month in vivo biocompatibility study was performed
in rabbits. No iritis, uveitis, retinal detachment. or corneal
decompensation was observed.
GT
Capsular Bag Refilling
GT
Capsular Bag Refilling
GT
THANK YOU
GT