COVER STORY Survey of Accommodating IOL...

OCTOBER 2010 CATARACT & REFRACTIVE SURGERY TODAY EUROPE 53

With the push toward refractive cataract surgery, presbyopia-correcting IOLs are steadily gaining popularity,

both with surgeons who are implanting them and with patients who are asking for them. An abundance of

multifocal and accommodating IOLs are currently available, and there are more models on the horizon. One

area of intense focus is the search for a truly accommodative lens technology. For now, several pseudoaccom-

modating lenses are either currently available or in the pipeline. The following questions were sent to a panel of anterior

segment surgeons who have experience implanting accommodating IOLs.

1. Do you have any experience with this lens, either in practice or in clinical testing? If so, how many have you

implanted?

2. Whether or not you have personal experience with this lens, what is your impression of its mechanism of

accommodation? Why does it work, or what in its current design limits it from working?

3. What are the advantages of the lens design? The disadvantages?

4. Who is the ideal candidate for this lens? What tips do you have for implanting this lens or optimizing

postoperative visual acuity?

5. What is your opinion on the future of this lens technology?

This survey is intended to offer a sampling of thoughts on eight accommodating IOL technologies: the Akkommodative 1CU

(HumanOptics AG, Erlangen, Germany), the Crystalens AO (Bausch + Lomb, Rochester, New York), the FluidVision (PowerVision,

Inc., Belmont, California), the NuLens DynaCurve (NuLens, Ltd., Herzliya Pituach, Israel), the SmartIOL (Medennium, Inc., Irvine,

California), the Synchrony (Abbott Medical Optics Inc., Santa Ana, California), the Tek-Clear (Tekia, Inc., Irvine, California), and the

Tetraflex (Lenstec, St. Petersburg, Florida). Vision Solutions Technologies (Rockville, Maryland) asked that its LiquiLens not be

featured in this survey. Some responses contain forward-looking thoughts and are not necessarily intended to provide clinical infor-

mation. In some cases, the participant did not respond about a particular lens, and therefore that set of questions was left out.

VICTOR BOHÓRQUEZ,MD

I am currently the Chief of Ophthalmology at

Saludcoop EPS – Servioftalmos, in Bogota,

Colombia. I have been implanting accommodating IOLs for

the past 6 years, and most of my experience has been in

clinical research trials with the Synchrony dual-optic IOL

(Visiogen Inc.; now Abbott Medical Optics Inc., Santa Ana,

California). I have also started implanting the Crystalens HD

(Bausch + Lomb, Rochester, New York) this past year. My

experience is based on these two accommodating IOLs.

Currently, I implant accommodating lenses in approxi-

mately 10% of cataract patients. This percentage is increas-

ing fairly quickly and will rapidly outgrow my percentage of

Survey ofAccommodating IOL

TechnologiesA panel of anterior segment surgeons provides answers to five questions.

BY VICTOR BOHÓRQUEZ, MD; SHERAZ M. DAYA, MD, FACP, FACS, FRCS(ED), FRCOPHTH;

ROBERT K. MALONEY, MD; SAMUEL MASKET, MD; MARK PACKER, MD, FACS;

MAGDA RAU, MD; AND SUNIL SHAH, FRCOPHTH, FRCS(ED), FBCLA

COVER STORY

multifocal IOL patients. I prefer implanting accommodating

lenses in younger patients because I believe it is a better way

to restore natural physiological accommodation and pro-

vide good quality of vision at all distances. Multifocal IOLs

split incoming light rays into two or more focal points, thus

producing uncomfortable photic phenomena.

It is important to mention that there is still no specific

IOL that fulfills all needs for all patients. It is ultimately up to

the surgeon to carefully select the correct IOL for the

patient’s individual lifestyle. The challenge for current and

future accommodating IOL technologies is to prevent fibro-

sis and maintain capsular clarity. A functioning capsule is

essential for the accommodative mechanism to work prop-

erly. As imaging technologies advance, so will IOL design.

When accurate capsular bag and ciliary muscle strength

measurements are finally possible, custom-designed IOLs

will become reality.

AKKOMMODATIVE 1CU 1. Do you have any experience with this lens, either in

practice or in clinical testing? If so, how many have you

implanted?

Even though I do not have personal experience with this

lens, it has been on my radar for a while because it was one

of the first accommodating lenses available in the world.

2. Whether or not you have personal experience with

this lens, what is your impression of its mechanism of

accommodation? Why does it work, or what in its current

design limits it from working?

The lens has four flexible haptics, which should allow

back-and-forth movement; however, published data from

several nonrandomized and randomized controlled clinical

trials show limited objective accommodative effect.1-4

3. What are the advantages of the lens design? The dis-

advantages?

Capsular fibrosis seems to be a problem, with high

Nd:YAG rates. There are also reports of haptics bent inward,

toward the rhexis edge.

4. Who is the ideal candidate for this lens? What tips do

you have for implanting this lens or optimizing postoper-

ative visual acuity?

[No answer provided.]

5. What is your opinion on the future of this lens tech-

nology?


CRYSTALENS AO 1. Do you have any experience with this lens, either in


implanted?

I do not have experience with the new version of the

Crystalens, the AO, but I have implanted more than 60 eyes

with the Crystalens HD.





I cannot speak for the Crystalens AO. In terms of the HD,

it incorporates a small magnitude of negative spherical aber-

ration within the central 1.5-mm diameter region of the 5.0-

mm optic. This negative spherical aberration is expected to

improve intermediate and near vision by increasing the

depth of focus. The mechanism of action of this lens

remains unproven.


advantages?





Most of my HD patients are satisfied, and the lens fulfills

most of their needs. These cataract patients accept the possi-

bilities of needing reading glasses for small print and of

decreases in contrast sensitivity. The HD lens is a good option

for patients who are worried about glare and halos and will

accept low-powered glasses for reading. I tend to target mini-

monovision with 0.25 D in the dominant eye and -0.25 D in

the fellow eye, as recommended by Bausch + Lomb.


nology?


FLUIDVISION1. Do you have any experience with this lens, either in


implanted?

I have no experience implanting this IOL.





My understanding is that this IOL works by moving

fluid from the haptics into a bladder in the center of

the lens. This movement alters the anterior radius of

curvature and shifts the lens forward.

54 CATARACT & REFRACTIVE SURGERY TODAY EUROPE OCTOBER 2010

COVER STORY

The design could be limited by the development of cap-

sular fibrosis. In case of capsular fibrosis, more fluid would

be needed to produce a greater magnitude of accommoda-

tion, or, even worse, the lens could get stuck at a single focal

point, resulting in large refractive errors.


advantages?







nology?


NULENS DYNACURVE1. Do you have any experience with this lens, either in


implanted?

I have no experience with this lens.





I understand that the flexible polymer, located between

two rigid plates, moves posteriorly with accommodative

effort to decrease the power of the eye (contrary to human

accommodation, which increases the power of the eye to

see near objects clearly).


advantages?

It may be awkward to ask patients to learn to see near

objects by disaccommodation and to do activities like driv-

ing or watching a movie by forcing accommodation.

Another issue with this lens is that it must be placed in the

ciliary sulcus; it is a big lens that may cause iris chafing with

resulting inflammation and/or pigmentary dispersion.






nology?


SYNCHRONY 1. Do you have any experience with this lens, either in


implanted?

I have implanted the Synchrony in more than 300 eyes.





The rear optic of this one-piece, dual-optic accommodat-

ing IOL is a minus lens, with a power chosen to produce the

desired overall net IOL power in the patient’s eye. The front

optic, which is mobile, is always 32.00 D, which inherently

provides more accommodation per unit of movement

compared with single-optic designs (Figure 1). Also, the

Synchrony provides consistent accommodative amplitude

regardless of lens power.

Our group has been able to show, utilizing several objec-

tive techniques including ultrasound biomicroscopy and

iTrace wavefront aberrometry (Tracey Technologies, Corp.,

Houston), that the lens works according to the Helmholtz

theory of accommodation. With accommodation (near

stimulus), the ciliary body contracts, releasing zonular and

capsular bag tension and allowing forward movement of

the anterior optic of the IOL. This results in an increase in

the power of the eye (ie, myopization).


advantages?

The only disadvantages I have observed are refractive sur-

prises in some patients and restricted movement of the

anterior optic in others. Extreme capsular bag sizes can

cause refractive errors or lack of anterior lens movement.

Currently, we do not have an accurate method of predicting

capsular bag volume; however, in the future, if we could


COVER STORY

Figure 1. The difference in accommodative amplitude

between dual- and single-optic lenses, per millimeter of

movement.

Courtesy of Victor Bohórquez,MD

measure or estimate the strength of the ciliary muscle and

capsular bag volume preoperatively, we could better choose

the appropriate technology and lens size that best fits the

patient’s anatomy.

When compared with other accommodating IOLs

and the multifocal IOLs currently available, the

Synchrony provides uninterrupted vision at all dis-

tances through physiologic accommodation.5-7 The

most powerful advantage of this lens is that the sub-

jective and objective evaluations of accommodative

amplitude correlate and show approximately 2.00 to

3.00 D, suggesting real and natural accommodation.

Additionally, the Synchrony is the only IOL that com-

pletely fills the capsular bag, keeping the anterior and

posterior capsules apart and thus limiting fibrosis

(Figure 2).




Our experience with this lens extends to 4 years’ follow-

up. Patients have excellent visual acuity at all distances, very

functional reading speed (comparable with multifocal IOLs

at newspaper print size), and lower incidence of glare and

halos than multifocal lenses.

As with other premium IOLs, a careful surgical tech-

nique is ideal. The Synchrony is provided in a preloaded

injector, and the lens is delivered into the capsular bag

in a consistently controlled fashion through a small inci-

sion. I attempt a perfect 5.0-mm continuous curvilinear

capsulorrhexis (CCC) by creating a guide before my inci-

sion with a 5.3-mm corneal marker.

With premium IOLs, I try to decrease the incidence of

capsular opacification by cleaning the capsular bag

completely, including polishing the undersurface of the

anterior capsule to remove lens epithelial cells. I prefer

bimanual I/A to achieve 360º polishing, including the

subincisional areas.

With any accommodating lens, I want to have a cap-

sule that remains clean and flexible to increase the

chances of success. The Synchrony has features that

help prevent anterior and posterior capsular opacifica-

tion. A system of fluid channels on the anterior optic

allows aqueous humor circulation between the bag

and the anterior chamber and keeps the CCC edge

raised, preventing rubbing between the optic and the

lens epithelial cells, thus inhibiting lens epithelial cell

fibrous metaplasia (a precursor of anterior capsular

opacification).


nology?


TETRAFLEX1. Do you have any experience with this lens, either in


implanted?






The Tetraflex is another single-optic IOL that is much

like the Crystalens in its design and anticipated mode of

action.


advantages?

Based on my experience with other accommodating

lenses, I am skeptical of this IOL’s ability to generate a

significant magnitude of accommodation with vitreous

displacement alone.






nology?



COVER STORY

Figure 2. Transillumination photo 1 year after surgery of an

eye implanted with the Synchrony.

Cour

tesy

of Vi

ctor B

ohór

quez

,MD


COVER STORY

SHERAZ M. DAYA, MD,FACP, FACS, FRCS(ED),FRCOPHTHI work in both the government sector

(National Health Service; NHS) and run a private

organization that provides cornea, cataract, and

refractive surgery. I have been involved with accom-

modating lenses since 2002 and commenced with the

Crystalens AT-45. I have also used Crystalens’ later-gen-

eration lenses, the 5-0, the HD, and now the AO. In my

practice, I implant accommodating IOLs in 20% of

patients.

AKKOMMODATIVE 1CU 1. Do you have any experience with this lens, either

in practice or in clinical testing? If so, how many have

you implanted?




accommodation? Why does it work, or what in its cur-

rent design limits it from working?

I believe the lens works by moving forward as a result

of vitreous displacement from ciliary body contraction,

although this seems to be more dependent on capsule

malleability. I gather (anecdotally) that the lens ceases to

function once the capsule fibroses.

3. What are the advantages of the lens design? The

disadvantages?

Its advantages include four-point fixation and easy implan-

tation through a microincision with the correct injector.

4. Who is the ideal candidate for this lens? What tips

do you have for implanting this lens or optimizing



5. What is your opinion on the future of this lens

technology?

It will be surpassed by other technologies.

CRYSTALENS AO1. Do you have any experience with this lens, either


you implanted?

I have implanted more than 800 Crystalens IOLs since

2002 and have used the AT-45, the 5-0, the HD, and cur-

rently the AO.





This lens works both by vaulting forward as a result

of vitreous movement and by arching; the silicone

lens is flexible, and the configuration of the haptics

and the hinge seems to permit this process. The limi-

tation is its inconsistency of action. Almost all recipi-

ents obtain good distance and intermediate vision,

but only 67% get good near vision. Myopes seem to

do better, which is a little counterintuitive in that the

lens power is low; however, it is easily explained by

the fact that eyes with longer axial lengths have a

greater depth of focus.


disadvantages?

The AO version has a monocular aberration-free optic,

which ensures good visual quality and is forgiving of mild

centration and tilt. To reduce the incidence of tilt and

refractive change, we now routinely follow a suggestion

made by my co-chief medical editor, Erik L. Mertens, MD,

FEBOphth, which is to implant a capsular tension ring

(Ophtec BV, Groningen, Netherlands) in conjunction

with lens implantation.




Patients who absolutely must drive at night and can-

not risk the compromises associated with multifocal

lenses and night driving (eg, chauffeurs), those requir-

ing good unaided intermediate vision, and those in

whom a multifocal lens is a relative contraindication

Victor Bohórquez, MD, is with the Department of

Ophthalmology at Servioftalmos, Bogotá, Colombia. Dr.

Bohórquez states that he is a paid consultant to Visiogen (now

part of Abbott Medical Optics Inc.). He may be reached at

e-mail: [email protected].

1.Findl O, Leydolt C.Meta-analysis of accommodating intraocular lenses.J Cataract Refract Surg..2007; 33:522-527.2.Findl O, Kriechbaum K, Menapace R, et al. Laserinterferometric assessment of pilocarpine-induced movement of

an accommodating intraocular lens:a randomized trial.Ophthalmol.2004;111(8):1515-1521.3.Schneider H, Stachs O, Go¨bel K, Guthoff R.Changes of the accommodative amplitude and the anterior chamberdepth after implantation of an accommodative intraocular lens.Graefes Arch Clin Exp Ophthalmol. 2006; 244:322-329.4.Uthoff D, Gulati A, Hepper D and Holland D.Potentially Accommodating 1CU Intraocular Lens:1-year Results in 553Eyes and Literature Review.J Refract Surg. 2007;23(2).5.McLeod SD, Portney V,Ting A.A dual optic accommodating foldable intraocular lens.Br J Ophthalmol.2003;87:1083-1085.6.McLeod SD,Vargas LG, Portney V,Ting A.Synchrony dual-optic accommodating intraocular lens.Part 1:Optical andbiomechanical principles and design considerations.J Cataract Refract Surg.2007; 33:37-46.7.Ossma IL, Glavis A,Vargas LG,Trager MJ, et al.Synchrony dual-optic accommodating intraocular lens.Part 2:Pilotclinical evaluation.J Cataract Refract Surg.2007; 33:47-52.

(eg, patients with glaucoma, age-related macular

degeneration, diabetes) are good candidates.


technology?

It is a useful lens to have in our surgical armamen-

tarium. Other technologies that function similarly and

do not reduce contrast sensitivity may well replace

this lens, unless a new iteration of the implant is

developed to provide increased reliability in terms of

lens movement.

FLUIDVISION 1. Do you have any experience with this lens, either


you implanted?


2. Whether or not you have personal experience

with this lens, what is your impression of its mecha-

nism of accommodation? Why does it work, or what in

its current design limits it from working?

It has an interesting mechanism of action. The sustain-

ability of action might be an issue and may be reduced

as a result of capsular fibrosis. Further investigation is

required.


disadvantages?

One advantage is the potential for a large amplitude of

accommodation. In terms of disadvantages, there is pos-

sible decreased performance with time. I would be inter-

ested to know about visual performance and aberrations

at different levels of accommodation.




Any patient could be a potential candidate, as long as the

device works and does not produce any optical aberrations.


technology?

Unsure, but the future looks good if it works long-term.

Sheraz M. Daya, MD, FACP, FACS, FRCS(Ed), FRCOphth,

is Director and Consultant of Centre for Sight and the

Corneoplastic Unit and Eyebank, Queen Victoria Hospital,

East Grinstead, United Kingdom. Dr. Daya is the Chief

Medical Editor of CRST Europe. He states that he is a con-

sultant to Bausch + Lomb. He may be reached at e-mail:

[email protected].


COVER STORY

ROBERT K. MALONEY, MDI am in a group private practice in Los Angeles.

Our center has been implanting accommodat-

ing IOLs since 2006. Accommodating IOLs are

used in approximately 25% of our cataract sur-

gery patients currently.

AKKOMMODATIVE 1CU 1. Do you have any experience with this lens, either in


implanted?






The accommodative mechanism is similar to the

Crystalens; with soft flexible haptics, the optic will move

forward in response to vitreous pressure.


disadvantages?

The four-haptic design fills the capsular bag, dis-

tending it. This distension may improve the ability of

the ciliary body to generate the accommodative force

on the lens.




I have no opinion.


technology?

Because the accommodative mechanism is similar to

the Crystalens, I expect the lens to have a future similar

to that lens.



you implanted?

I use either the Crystalens AO or the Crystalens HD in

approximately 25% of my premium IOL patients.





The lens accommodates when vitreous pressure

induces either forward movement of the lens or a distor-

tion of the lens, leading to an increase in spherical aber-

ration with increased depth of focus.


disadvantages?

The two-haptic design is easy to insert and requires

no significant changes in surgical technique from stan-

dard cataract surgery. Because the positioning loops at

the ends of the plate haptics become encased in the

capsular bag, the haptics cannot be explanted once the

bag fibroses, and the haptics must be amputated.

However, because of the good optical performance of

the lens, explantation is rarely necessary.




The optimal candidate is a patient who requires excellent

distance and intermediate visual acuity, is willing to sacrifice

near visual acuity, and would be intolerant to the increased

night glare that accompanies multifocal lenses. Because the

lens is flexible, the refractive outcome is slightly less accurate

than with a standard monofocal lens, so the surgeon must

be prepared and able to perform a laser corneal surgical

refractive enhancement postoperatively.


technology?

The lens has a secure position in our armamentarium now

because it offers an alternative for patients who want a premi-

um IOL but who are intolerant of the night glare of multifocals.

FLUIDVISION1. Do you have any experience with this lens, either


you implanted?


Figure 3. A Synchrony accommodating IOL in the eye 2 years

postoperatively.The capsule remains quite clear, possibly

because the IOL completely fills the capsular bag.

Courtesy of Robert K.Maloney,M

D





Because the lens relies on the movement of fluid

behind the membrane, it potentially has a much greater

amplitude of accommodative power than a solid lens.


disadvantages?







technology?


SYNCHRONY 1. Do you have any experience with this lens, either


you implanted?






The Synchrony entirely fills the capsular bag (Figure 3),

maximizing ciliary action. The combination of its plus and

minus optics increases its accommodative response to cil-

iary movement.


disadvantages?







technology?

I am looking forward to adding this lens to my practice

when it is available in the United States.

TETRAFLEX 1. Do you have any experience with this lens, either


COVER STORY

SAMUEL MASKET, MDMy practice concerns mainly complex anterior

segment cases. As a result, I see a relatively small

number of routine cataract candidates, limiting

the number of patients who are eligible for either

multifocal or accommodating IOLs. With that

said, I have implanted accommodating IOLs for nearly 3

years and they represent between 5% and 10% of my cases.

All surgery is performed at Specialty Surgery Center, an out-

patient center dedicated to anterior segment eye surgery.

AKKOMMODATIVE 1CU1. Do you have any experience with this lens, either in


implanted?

I have no clinical experience with the Akkommodative1CU,

as it is not available in the United States.





Given low market interest where available and because it

has been on the market for several years, I doubt that it

achieves much accommodation.


disadvantages?

Today, focus-shift, single-optic IOLs are of limited value.






technology?

In my opinion, the future of this technology is limited.



you implanted?

I have implanted approximately 100 of these lenses.





Its mechanism of accommodation is speculative; in

concept, it is a single-optic, focus-shift lens with little


you implanted?






The accommodation of this lens may occur when ciliary

pressure causes the lens to flex, inducing a change in spheri-

cal aberration and increasing the depth of focus. The lens

has a four-haptic design and is vaulted anteriorly, which may

improve the response of the lens to ciliary movement.


disadvantages?







technology?


A FINAL COMMENTWe are moving into a generation of accommodating

lenses with accommodative amplitudes dramatically

increased over what has been previously available. An

unrecognized problem with these lenses is that they

will have less refractive accuracy than the lenses we are

used to. The reason for this is simple: these lenses are

designed to respond to small changes in the ciliary

force with large changes in refractive power.

Because of variations in the sizing of human eyes and

variations in capsular bag contraction, the resting force

on the lens with the ciliary muscle relaxed will vary sig-

nificantly from patient to patient. Therefore, many of

these lenses will be in a partially accommodated state

even with the ciliary muscle relaxed. We should expect

to see larger spherical refractive errors in these lenses

than we are accustomed to. To use these lenses, the

cataract surgeon will need to be an expert refractive

surgeon as well.

Robert K. Maloney, MD, is the Director of the Maloney

Vision Institute in Los Angeles. He states that he is a con-

sultant to Abbott Medical Optics Inc. and is a consultant to

and an owner or shareholder in Calhoun Vision, Inc. Dr.

Maloney may be reached at tel: +1 310 208 3937; e-mail:

[email protected].


COVER STORY

true movement demonstrated. Some patients have an

improved accommodative range over monofocal lens

designs, but this is not predictable. The Crystalens HD

model improved near visual acuity but at the expense of

vision quality and IOL power predictability.


disadvantages?

The disadvantages include the size of the optic (5

mm), lack of a UV-absorbing chromophore, and its

flexible haptics, which, in combination with postopera-

tive capsular fibrosis, leads to mild to severe Z syn-

drome.




This lens serves those who desire reduced spectacle

dependence and are willing to accept limited near

UCVA. Patients are best served with mini-monovision.

During implantation, it is imperative to clean anterior

subcapsular lens epithelial cells and to cover the hap-

tics with the anterior capsule to prevent Z syndrome. I

prefer an ovoid capsulorrhexis, placing the long axis of

the optic perpendicular to the short axis of the capsu-

lotomy. I offer this IOL to those who are not appropri-

ate candidates for multifocal IOLs.


technology?

It will be replaced by evolving IOLs.



you implanted?

No personal experience; however, I am a member of

the medical advisory board.





Accommodation is accomplished by transfer of fluid

from the haptic reservoirs to a bladder within the optic

on accommodative demand (Figure 4). It has been

demonstrated to work in the laboratory and in a small

number of humans.


disadvantages?

The advantages include adequate range of accommo-

dation. Disadvantages include its novel technology, sizing

issues of the capsular bag, and the necessary incision size

of approximately 5 mm.





Figure 4. A prototype of the FluidVision IOL.

Figure 5. Cadaver eye after SmartIOL implantation and

subsequent removal of the cornea for visibility.The SmartIOL

is designed to fill the capsular bag.

Figur

es 4

and 5

cour

tesy

of Sa

mue

l Mas

ket,M

D


COVER STORY


technology?

This lens will soon enter clinical trials.

NULENS DYNACURVE1. Do you have any experience with this lens, either


you implanted?

I have implanted this IOL only in the wet lab setting.





Reverse accommodation is achieved by impaling the

haptics in the ciliary body, avoiding the need for capsular

bag shape change.


disadvantages?

The main advantage is the potential for sulcus place-

ment, which may also be disadvantageous. The major

disadvantage is its mechanism of reverse accommoda-

tion.






technology?

Speculative.

SMARTIOL1. Do you have any experience with this lens, either


you implanted?

I have done prior laboratory testing in a few cadaver

eyes (Figure 5).





Its full-sized optic allows transmission of capsular

forces to induce IOL shape change.


disadvantages?

Advantages include its full-size hydrophobic acrylic

thermoplastic optic. The disadvantages include IOL sizing

and flexibility of material.




No information at this time.


technology?

Speculative but hopeful.

SYNCHRONY1. Do you have any experience with this lens, either


you implanted?

None implanted.





This lens’ double-optic Galilean telescopic design pro-

vides the mechanism of accommodation, allowing true

accommodation.


disadvantages?

Advantages include its double optic, which fills the

capsular bag. The major disadvantages are the large

incision size required and the need for perfect sur-

gery.






technology?

This lens will likely have favorable market position for

several years.

TETRAFLEX1. Do you have any experience with this lens, either


you implanted?







COVER STORY

MARK PACKER, MD, FACSI practice in the beautiful valley town of

Eugene, Oregon, nestled between coastal hills

and the towering Cascade Mountain volcanic

peaks, home to the University of Oregon, the

birthplace of Nike footwear, and the last refuge

of the 1960s generation. Our private practice and surgery

center enjoy a reputation for superb, state-of-the-art

cataract and refractive surgery, built and maintained for

more than 40 years by offering the most advanced and

effective technologies and delivering them with genuine

care for each person who trusts his or her sight to us.

This year to date, 35% of my patients have opted for

presbyopia correction at the time of cataract surgery. Of

these patients, 20% have received an accommodating

lens (the Crystalens AO is the only accommodating IOL

currently available in the United States; however, I am an

investigator for the Synchrony and have implanted it

under an Investigational Device Exemption [IDE] in some

cases). The other 80% of patients have received multifo-

cal IOLs, predominately the Tecnis Multifocal (Abbott

Medical Optics Inc.). In general, currently available multi-

focal IOLs provide a higher level of spectacle independ-

ence than the Crystalens—albeit at the cost of some

reduction in quality of vision. However, for patients moti-

vated to live without glasses, multifocal lenses achieve a

high level of satisfaction. Future accommodating lenses

should achieve a higher level of spectacle independence

by providing a greater amplitude of accommodation or

pseudoaccommodation and preserve high-quality vision

with low overall optical aberrations.

AKKOMMODATIVE 1CU 1. Do you have any experience with this lens, either


you implanted?

I have no personal experience with this lens.





I remember its launch with great fanfare at the European

Society of Ophthalmology (SOE) in Istanbul, Turkey, in

2001; however, to the best of my knowledge, it has not

demonstrated more than 1.00 D of accommodation.


disadvantages?

There have been reports of capsular contraction and

centripetal movement of the haptics.






technology?

Unless improvements in its design are forthcoming, I

do not believe the 1CU will remain a viable entry.

CRYSTALENS AO 1. Do you have any experience with this lens, either


you implanted?

I have extensive experience with the Crystalens, begin-

ning as an investigator in 2000 with the AT-45 and span-

ning the decade since.





Axial movement was the initial conceptual mechanism

The lens has a single optic and the haptics are flexible.

However, it is a focus-shift IOL.


disadvantages?

Advantages include simple insertion and acrylic mate-

rial. A disadvantage is limited accommodation due to the

single-optic, focus-shift design.






technology?

Should it receive US Food and Drug Administration

(FDA) approval, it will have some impact on the mar-

ket, although its accommodative function is limited.

Samuel Masket, MD, is a Clinical Professor at the David

Geffen School of Medicine, UCLA, and is in private practice

in Los Angeles. Dr. Masket states that he has no financial

interest in the products or companies mentioned. He may

be reached at tel: +1 310 229 1220; e-mail:

[email protected].


COVER STORY

of this lens, but it has not been demonstrated to move

significantly. Alternative explanations for its clinical effec-

tiveness include arching, bending, and high spherical

aberration. The FDA approval for the Crystalens

described 1.00 D of accommodation, and I believe this

accurately represents a mean minimum. Some patients

achieve higher levels of function, perhaps from

pseudoaccommodative mechanisms.


disadvantages?

I had minimal trouble with complaints of halo after

Crystalens HD implantation, but I have heard of this

phenomenon from other surgeons. The current AO

design provides optical quality similar to a monofocal

IOL.




I continue to recognize that some patients do

extraordinarily well with this technology, and that these

patients tend to be axial myopes with minimal astigma-

tism and little to no residual refractive error. It is not

unusual to achieve 20/20 and J2 or better vision in this

group. On the other hand, the majority of patients

implanted bilaterally with any model of the Crystalens

should be counseled to expect to wear low-power read-

ing glasses postoperatively (usually 1.25 to 1.50 D). I

continue to offer the Crystalens AO, primarily for

patients who specifically request it and secondarily for

patients who wish to reduce their need for glasses but

are averse to halos or dysphotopsia. I discourage hyper-

opes and patients with higher degrees of keratometric

cylinder preoperatively unless they are comfortable

with the high likelihood (about 15%) of an excimer laser

enhancement procedure afterward.


technology?

The Crystalens is currently experiencing a declining

market share in the United States; however, it has been

reimagined and redesigned several times and may have

yet another rebirth in store.



you implanted?

I have seen the design of the FluidVision lens and heard

some reports about it at meetings. I have no personal

experience.





I believe the concept could be effective; however, I am

concerned about long-term safety.


disadvantages?

It may provide substantial accommodation.






technology?

This design has some potential; however, there is a long

clinical row yet to hoe.

NULENS DYNACURVE1. Do you have any experience with this lens, either


you implanted?

I have no personal experience.





The NuLens represents a captivating and innovative

idea; however, its embodiment is complex and fraught.


disadvantages?

This design has the ability to provide high amounts of

accommodative amplitude through changes in the sur-

face curvature of the deformable piston. The device is

fairly complex and much different from anything we have

experienced before.






technology?

This technology has developed a great deal since I first

became aware of it. With greater simplification, it may

yet prove itself.

SMARTIOL1. Do you have any experience with this lens, either in


implanted?






The SmartIOL has been off my radar screen for some time.

Several years ago it was a hot topic, with benchtop videos of its

expansion in warm water and its inherent flexibility.


advantages?

Simple, straightforward and easy to implant, it seemed at

the time to be a winner design. Even the potential compli-

cation of posterior capsular opacification seemed manage-

able because Nd:YAG capsulotomy would not be con-

traindicated. At the moment, I am wondering what became

of the SmartIOL.


do you have for implanting this lens or optimizing post-

operative visual acuity?



nology?


SYNCHRONY1. Do you have any experience with this lens, either in


implanted?

As a US investigator for this lens, I have been able to

implant it under an IDE in some cases.





The Synchrony represents a unique combination of origi-

nal design, ingenuity, and functionality. I have been

extremely impressed by the demonstration of forward

movement of the anterior optic with ultrasound biomi-

croscopy under ciliary body contraction.


advantages?

The resultant 2.00 to 3.00 D of accommodation provides

Visit us at AAO

MAGDA RAU, MD

In Germany, I practice in the hospital setting at

Augenklinik Cham and also am in private prac-

tice at Refractive Privatklinik-Dr.Rau, both in

Cham. I also practice at Eye Centre Prag in the

Czech Republic. I have been implanting accommodating

IOLs for the past 9 years. Currently, I use accommodative

technologies in 15% of my cataract patients.

AKKOMMODATIVE 1CU1. Do you have any experience with this lens, either

intermediate vision that outperforms multifocal IOLs and

near vision that matches them, without the induction of

aberrations. The persistent clarity of the capsule beyond

3-year follow-up is an unexpected benefit of this IOL.




The surgical technique demands a precise capsulor-

rhexis and careful cortical clean-up; the injector provides

a simple and predictable method of implantation.


technology?

Acquired by Abbott Medical Optics Inc. last year, the

Synchrony is awaiting FDA approval. I believe it has the

potential to become a dominant market player in the

near-term.

TEK-CLEAR1. Do you have any experience with this lens, either


you implanted?






The Tek-Clear is a lens within a ring; it is a bending,

accommodating IOL. It is not available in the United States.


disadvantages?

It is a simple design, but one that does not appear to

have the potential for greater accommodative amplitude

than the Tetraflex or the Crystalens.






technology?

I do not see this IOL garnering a significant market share.



you implanted?






The Tetraflex reportedly works through a bending-

and-flexing mechanism, with changes in surface curva-

ture and possibly some axial movement.


disadvantages?

The Tetraflex appears to provide a range of function

similar to the Crystalens.






technology?

The Tetraflex may have some adherents, but is unlikely

to be a big winner in the market place.

Mark Packer, MD, FACS, is a Clinical Associate Professor

at the Casey Eye Institute, Department of Ophthalmology,

Oregon Health & Science University, and is in private prac-

tice at Drs. Fine, Hoffman & Packer, LLC, Eugene, Oregon.

He states that he is a paid consultant to Abbott Medical

Optics Inc., Advanced Vision Science, Bausch + Lomb, Carl

Zeiss Meditec Surgical, Inc., Celgene Corp., Corinthian

Ophthalmic Inc., GE Healthcare, Haag-Streit USA, Ista

Pharmaceuticals, Inc., and Rayner Intraocular Lenses, Inc.,

and holds stock options with LensAR, Inc., Surgiview LLC,

Corinthian Ophthalmic, Inc., Transcend Medical, Inc.,

TrueVision Systems, Inc., and WaveTec Vision Systems. Dr.

Packer may be reached at tel: +1 541 687 2110; e-mail:

[email protected].

COVER STORY



you implanted?

I have used the 1CU regularly since 2001; I have

implanted approximately 500.



nism of accommodation? Why does it work, or what

in its current design limits it from working?

The accommodative function is based on the focus-shift

principle; the flexible geometry and composition of the

four haptics allow the IOL to move forward in correspon-

dence with the ocular structures such as the ciliary muscle.

Successful performance of the lens depends on the healthy

physiology of the accommodating structures of the eye.

A forward lens movement of 0.64 to 1.10 mm achieves

0.50 to 1.80 D of accommodation. Higher lens powers (start-

ing at 23.00 D) increase the amount of pseudoaccommoda-

tion. Additionally, according to the principle of the conoid of

Sturm (astigmatmus inversus against-the-rule), astigmatism

of -0.50 to -1.25 D increases the amount of pseudoaccom-

modation achieved after the implantation of 1CU.


disadvantages?

Pseudoaccommodation is achieved through deforma-

tion of the haptics, so the monofocal nature of the lens

optic avoids the typical side effects (eg, glare and halos)

associated with multifocal IOLs. Patients do not have to

get used to two different foci, which for some is difficult.

In my opinion, the greatest advantage of this lens is that it

can be offered to patients who wish to be spectacle inde-

pendent but do not want to compromise distance vision;

who drive a lot at night; or who work in an illuminated

environment, such as under spotlights on the stage.

The disadvantage is that the achieved accommoda-

tion is usually only 1.00 to 2.00 D, contraindicating

patients who want 100% spectacle independence.




The ideal candidate wants spectacle independence in

daily life; these are active people who work on the com-

puter, play sports and cards, go to the cinema, and drive

at night. Candidates who read often, work a lot at near,

and desire complete spectacle independence are not ideal

candidates for this IOL. I usually start with the dominant

eye and calculate the refraction target for plano. After 1

month, if the patient requires better near vision, I calcu-

late the lens for the nondominant eye for between -0.50

and -1.25 D. I implant the 1CU through an astigmatically

eyetube.net

b

The world’s

#1online source for

ophthalmic videos

Thousands of videoswith audio tracks

•High-Definition

video•

Links to articles•

watch + listen + learn

www.eyetube.net

Find us on

&

neutral clear corneal incision. It is important to perform a

well-centered rhexis, without any peripheral tears and not

exceeding 5 mm in diameter, to ensure that the capsule is

stable enough to withstand any IOL movement. As it

might hinder the shift of the IOL, no capsular tension ring

should be used. Patients with symptoms that might hinder

the accommodative mechanism, such as pseudoexfolia-

tion syndrome, synechia, phacodonesis, or damaged

zonules, should be fit with another IOL.


technology?

In my practice, I use the 1CU as a complement to multifocal

IOLs. This lens addresses the needs of patients who wish to

achieve spectacle independence. In the future, it may be possi-

ble to combine the flexible haptics with movement-induced

changes of the lens optic material. This could increase

pseudoaccommodation to 3.00 D. I think that there will con-

tinue to be further need for accommodating IOLs, because

although multifocal IOLs continue to emerge in the market,

not every patient is a good candidate for this lens design.



you implanted?

I have implanted approximately 10.







disadvantages?

In my opinion, results after implantation of the Crystalens

AO are comparable with results after implantation of the

Akkommodative 1CU. Therefore, the advantages and disad-

vantages of both IOLs are nearly the same.




For patients to achieve more spectacle independence, I

correct the nondominant eye to -0.50 or -1.00 D. Women

seem to tolerate slight monovision better than men. In my

experience, 25% of women and 15% of men have been able

to adapt to monovision. For this reason, I usually target

higher monovision in women than in men. We examine the

tolerance of monovision preoperatively with test glasses or

contact lenses. Even after 10 minutes with test glasses,

patients can usually tell if they will tolerate monovision.


technology?


TEK-CLEAR1. Do you have any experience with this lens, either


you implanted?

I have implanted three lenses thus far.





The Tek-Clear is a successful attempt to simulate the

human lens. Designed to take advantage of the natural

accommodating process of the human eye, the lens hap-

tics and optic incorporate a bending-beam approach

that fully optimizes IOL movement as the ciliary muscle

contracts and relaxes during accommodation.


disadvantages?

Unfortunately, even though the lens is very flexible, with

its large diameter it is difficult to implant. The accommoda-

tion achieved in our hands with this lens was 1.00 D.






technology?


Magda Rau, MD, is the Head of the Augenklinik Cham

and Refractive Privatklinik-Dr.Rau, Cham, Germany, and

Eye Centre Prag, Czech Republic. Dr. Rau states that she has

no financial interest in the products or companies men-

tioned. She may be reached at tel: +49 9971 861076; e-mail:

[email protected].


COVER STORY

Would you like to comment on an author’s article? Do you have an article topic to suggest?

Do you wish to tell us how valuable CRST Europe

is to your practice? Please e-mail us at [email protected] with any thoughts, feel-

ings, or questions you have regarding this publication.

SHARE YOUR FEEDBACK

SUNIL SHAH, FRCOPHTH,FRCS(ED), FBCLA

I work both in the Midland Eye Institute, a dedi-

cated private ophthalmic day hospital, and the

Birmingham and Midland Eye centre, an NHS

hospital, both in the United Kingdom. I have

been using accommodating lenses for more than

6 years, both for research trials and in routine practice. I use

accommodating IOLs for appropriate patients and feel that

they are a necessary part of my armamentarium to offer

patients a complete range of choices.

AKKOMMODATIVE 1CU1. Do you have any experience with this lens, either


you implanted?

I have implanted 50 lenses. Initially, this was part of a study.8





Theoretically, it is the focus-shift principle that pro-

vides the mechanism of accommodation. In practice, it is

probably lens flexing.


disadvantages?

I found the lens to be slightly fiddly to insert.

Additionally, in my experience, it provided only limited

pseudoaccommodation and had a high early posterior

capsular opacification rate.




I do not use this lens any longer.


technology?

Limited.



you implanted?


COVER STORY

66thth International Congress ofInternational Congress ofCorneal CrossCorneal Cross--LinkingLinking

January 21-22, 2011 - Milan/Italy

The CXL congress is an international forum for the most recent advancesin corneal cross-linking

For more information please contactFor more information please contact:CBS Congress & Business Services,

Technoparkstrasse 1, CH-8005 Zurich, SwitzerlandE-mail address: [email protected]

Registration form on: www.cxl-congress.org

www.cxl-congress.org





Like the Akkommodative 1CU, the mechanism is theo-

retically the focus-shift principle. However, in practice, it

is probably the lens flexing.


disadvantages?

There are few advantages other than the marketing by

the manufacturer.

4. Who is the ideal candidate for this lens? Do you

have any tips for implanting this lens or optimizing




technology?

Limited, given other lenses on the market now.

SYNCHRONY1. Do you have any experience with this lens, either


you implanted?

My only knowledge of this lens comes from presenta-

tions made at conferences.





The focus-shift principle works better in a lens with a

dual-optic design, such as this one.


disadvantages?

The advantage is that more pseudoaccommodation is

possible. However, it is a large lens and more difficult to

manage. Additionally, it may induce myopia for a few

weeks after surgery.






technology?

This is an interesting technology. I look forward to see-

ing whether it lives up to its potential.



you implanted?

I have implanted approximately 1,000. Initially this was

through a research study.9 I have recently completed

another research study on this lens.10





Theoretically, like the Akkommodative 1CU and the

Crystalens AO, the focus-shift principle is the mechanism of

accommodation, but in practice it is probably the lens flexing.


disadvantages?

The main advantage is that this lens is simple to use, as

it behaves just like a monofocal lens for insertion. It per-

forms very well on functional visual acuity testing even

though push-pull testing gives only a mean of approxi-

mately 1.60 D pseudoaccommodation. However, the pos-

terior capsular opacification rate is slightly high.




Anyone who desires good distance and intermediate

vision and some near vision, without the risk of dyspho-

topsias. This lens is ideal for micro-monovision or for

patients who are slightly myopic in both eyes.


technology?

This lens has good potential, and I understand it is due

to receive FDA approval soon. ■

Sunil Shah, FRCOphth, FRCS(Ed), FBCLA, is a Visiting

Professor at the School of Biomedical Sciences, University of

Ulster, Coleraine, Northern Ireland; Visiting Professor at the

School of Life & Health Sciences, Aston University, Birmingham,

UK; Medical Director, Midland Eye Institute, Solihull, UK; and

Consultant Ophthalmic Surgeon, Birmingham & Midland Eye

Centre, Birmingham, UK. Professor Shah states that he is a con-

sultant to Abbott Medical Optics Inc. and Lenstec Inc. He may

be reached at tel: +44 1217112020; fax: +44 1217114040; e-

mail: [email protected].

8.Wolffshon JS,Hunt OA,Naroo S,et al. Objective accommodative amplitude and dynamics with the 1CU accommoda-tive intraocular lens.Invest Ophthalmol Vis Sci. 2006;47:1230-1235.9.Wolffshon JS, Davies LN, Gupta N, et al.Mechanism of action of the Tetraflex accommodative intraocular lens. JRefract Surg.2010;28:1-5.10.Wolffsohn JS,Naroo SA,Motwani NK,et al.Subjective and objective performance of the Lenstec KH-3500 accommoda-tive intraocular lens.Br J Ophthalmol.2006;90(6):692-696.


COVER STORY

COVER STORY Survey of Accommodating IOL...

Documents

Transcript of COVER STORY Survey of Accommodating IOL...