MULTIFOCAL IOLS
From the 28th Annual Scientific Meeting, presented by the Utah Ophthalmology Society, Salt Lake City
Robert J. Cionni, MD, Medical Director, Cincinnati Eye Institute; Adjunct Clinical Associate Professor, University
of Utah; and Volunteer Assistant Professor, University of Cincinnati, OH
Multifocal Intraocular Lens (IOL) Technology
| Introduction: speaker involved in studies by 3M company in late 1980s and early 1990s; tested full optic diffractive
IOL similar to Tecnis lens without aspheric design; provided good distance and near vision but had
significant decrease in contrast sensitivity and associated with halos; never marketed
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| Array zonal refractive IOL: still used, but need to be selective; good distance vision and fair near vision; halos
and glare made it unacceptable
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| New multifocal IOLs (ReSTOR and ReZoom): lens design—ReSTOR lens modification of old 3M design;
ReZoom built on same platform as Array, with some modifications (decreased near zone further in periphery
of optic and increased distance portion of lens); intent to decrease halo with wider pupil; Food and Drug Administration
(FDA) trial results good, with 93% of patients having no need for glasses for distance, 93% not
needing for intermediate, and 81% not needing them for near; in speaker’s practice, ≈60% spectacle-free
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| ReSTOR lens: apodized diffractive optic; apodization means characteristic of lens changes from center of lens
to periphery; overall result improved clarity; center of lens diffractive grading, and characteristics of grading
change from center to periphery; at center of lens, ≈50% of available light set to distance focus; when pupils
small (eg, reading) and in good bright light, vision good; as pupils get larger, more light sent to distance focus
and less to near; improves contrast sensitivity with larger pupils and decreases effect of near vision focus
points, so fewer halos and less glare; multicenter FDA study results showed 84% of bilaterally implanted ReSTOR
patients obtained uncorrected vision (distance and near combined) of 20/25 and J2 (or better) without
glasses; if distance correction included, further improvement (correcting spherical error); more night vision
problems in general, compared to multifocal control, but results better than with Array lens; most (≈90%) of
complaints mild; 4% to 5% had bothersome complaints; inform patients before implanting lens about likelihood
of halos and glare; less scatter and glare with ReSTOR lens than with ReZoom; in FDA study, after bilateral
implantation of ReSTOR lens, 80% of patients never wore glasses again
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| Tecnis full optic diffractive lens: good near vision, even with dim light and wide pupil, but more significant
halos and glare (due to light being sent to near focus instead of distant focus)
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 | Study: bilateral ReSTOR compared to bilateral monofocal IOLs; evaluated at different time points, ending at 6
mo; looked at vision at different distances, contrast sensitivity, and quality of life; 100% of patients able to
read clock at distance; monofocal patients had problems with near vision (about one third could read tiny
print); almost 100% of bilateral ReSTOR patients could read tiny print; intermediate vision, however, another
reported downside; both groups reported being satisfied with reading computer monitor (computer font typically
J5 or J7; both groups, at arm’s length, can read J5 or better); both groups did well with shaving and styling
hair, and with night driving (which encompasses distance vision, near-to-intermediate vision, and trouble
with halos and glare); 90% of bilateral ReSTOR patients had no difficulty viewing items, while only one third
of monofocal patients had no difficulty; “mix and match”—92% of implanted multifocal lenses same style in
both eyes; 8% mix and match, with most having multifocal in one eye and monofocal in other eye; study—
ReSTOR lens implanted in one eye; after implantation, distance vision fairly good; intermediate and near vision
unacceptable; when same-style lens put in fellow eye, vision at all distances improved dramatically (due
to adaptation of brain in learning visual system); if patient complaining of halos and glare with ReZoom in
first eye, speaker would consider another style lens in other eye; if ReSTOR lens in first eye, speaker hesitant
to move forward with second eye; types of glare and halos—Maddox rod effect with fold in posterior capsule
(fold in capsule perpendicular to streak that patient sees); early on, folds tend to smooth out, but if present >1
mo, will not disappear; if yttrium-aluminum-garnet (YAG) laser used, symptom resolves; if patient has starburst
halos around lights, relatively clear posterior capsule, and good tear film, but not willing to accept halos,
may need lens explant; be certain that patient willing to give up near vision
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Pearls for Success
| FDA study: distance and near vision without glasses important to patient; uncorrected vision results as shown
by speaker, 20/25 or better (88%), 20/20 or better distance and near (63%), better than 20/20 distance and
near (53%); patients in study had very healthy eyes, good tear film, <1 diopter (D) of corneal astigmatism,
and older in age
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| Patient selection: quality of best corrected preoperative vision important; if patient can see 20/20 or 20/15 with correction
but has presbyopia, more difficult to make patient better; low myopes more difficult to please because they
can take off glasses and read; important to qualify preoperative refractive state; age, occupation, lifestyle, and hobbies
of patient important in determining needs; patient expectations also important; artery status important; in bilateral
implantation, important that summation present between 2 eyes; surface pathology—anything that creates less
than perfect medium (eg, opacity in tear film [blepharitis, dry eye], basement membrane disease with irregular epithelium,
posterior capsule opacification) more significant with multifocal lens than monofocal one; if zonular loss
present, and uncertain of ability to obtain centered implant, patient probably not good candidate; patients with issues
that will decrease final visual acuity (eg, epiretinal membrane, macular drusen) probably not best candidates;
some surgeons obtain optical coherence tomography (OCT) for multifocal patients as part of testing regimen; pupil
size—important; should check in dim and bright light and while dilated as part of work-up; ideal candidate—70
yr of age, hyperope with bilateral cataracts, no other ocular pathology, normal axial length, and corneal cylinder
≤0.5 D; good candidate—any cataract or refraction patient (one who requires glasses or contact lenses at all distances);
also patients with keratometric cylinders correctable to <0.5 D; limbal-relaxing incision (LRI) typically
performed at time of cataract surgery if patient has ≥0.75 D of cylinder; if patient correctable with LRI, astigmatic
keratotomy (AK), or laser refractive procedure, considered good candidate; also post–laser-assisted in situ
keratomileusis (LASIK) patient good candidate (most have little, if any, cylinder); poor candidates—hypercritical
patients; those with unrealistic expectations; those with high corneal cylinder uncorrectable with LRI, AK, or laser
refractive procedure; preexisting ocular pathology; previous radial keratotomy (RK) (notoriously poor candidates);
emmetropic presbyopes harder to please and considered poor candidates; low myopes less ideal candidates
than hyperopes (can remove glasses and read)
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| Patient education: to create realistic expectations; should begin well before patient sees surgeon; speaker provides
patient with brochures to read and educational video to watch before meeting; allow sufficient time with patient to
answer questions; warn patients about halos; explain differences between available technologies; limitations of
ReSTOR and ReZoom—patients who have large pupils under normal light conditions, may have some compromise
to their near vision in dim light (need to inform patients); advise patients considering ReSTOR that their intermediate
vision will be inferior to their near vision, but will improve with time; after ReZoom implanted, most
patients typically J1; tend to read better when light less bright because central portion of optic all distance (pupil
needs to be slightly dilated to get near refractive ring); inform ReZoom candidate that near vision will be inferior
to intermediate vision, and if they have small pupils, near vision in good light sub-par (also higher likelihood of
glare); speaker usually informs patients they have 80% chance of being spectacle-free for majority of day
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| Detailed work-up: careful examination; look for dry eye; speaker suggests multifocal patients use cyclosporine
ophthalmic emulsion (Restasis) preoperatively; treat blepharitis; look carefully for any retinal pathology; axial
length important; perform manual keratometry and make sure consistent with results from IOL Master and
topography (not only in amount of cylinder, but also in axis of cylinder); if not consistent, repeat (and do not
proceed until they do match); if unable to match, probably issue in cornea which was missed on examination;
reexamine and treat if necessary; if unable to get good readings, patient not good candidate; perform immersion
A-scan or IOL Master (more reproducible and much tighter A-constant than with applanation-style axial
length measurements); use new-generation formulas
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| Surgical technique: speaker prefers ambulatory surgery center to hospital setting (prepare patient for “retail-
type” environment); if corneal astigmatism present, reduce with LRI, unless performing photorefractive keratectomy
(PRK) or LASIK postoperatively; degree of corneal astigmatism must be ≤0.5 D; determine cylinder
induced by main incision, then can perform LRI when necessary; follow results; use published nomogram to
determine size of desired LRI; premark patient for horizontal and vertical axes while sitting upright (when patient
lying down, eye can torque as much as 30º); mark axis of intended center of LRIs (steep axis of cornea)
with axis marker or Mendez ring; put viscoelastic on cornea and use arcuate guide to obtain consistent length;
speaker puts sodium chondroitin sulfate and sodium hyaluronate solution (Viscoat) and 1 or 2 drops of balanced
salt solution (BSS) into cornea at beginning of procedure; not necessary to put more BSS into cornea
throughout procedure because it stays moist and clear
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| Follow-up: be involved in patient’s postoperative care; adequate time needed postoperatively to address patient’s
concerns; perform enhancements if necessary; for spherical error, speaker prefers “piggyback” IOL to LASIK
(less interventional; by not lifting up corneal flap, less likely to induce more dry eye; can use same incision used
during surgery [speaker uses STAAR AQ5010 because it fits nicely in sulcus; www.doctor-hill.com]; easy to
perform; and safer than lens exchange); if patient has residual cylindrical error, treat with LASIK or enhanced
LRI; follow outcomes and maintain database; if not achieving desired postoperative refractory result, adjust A-
constant based on outcomes; evaluate effect of LRIs; have patient complete at-home postoperative questionnaire
to determine whether their expectations met
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Toric IOLs
| Characteristics: patients who have toric IOLs not as difficult to please as those with multifocal IOLs; patients
with corneal cylinder good candidates; even if patient developing keratoconus where not performing LRI (but
if removing cataract and patient does not yet need transplant), able to reduce astigmatism significantly with
toric lens; previous-style lenses had limited cylindrical powers, did not take into consideration induced cylinder
from incision, and had silicone plate design, which could rotate more than single-piece acrylic lens; FDA
study showed lens does not rotate off axis; AcrySof toric lens found superior to STAAR toric lens; 97% of patients
in FDA study spectacle-free for distance vision when toric lens implanted bilaterally
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| Surgical technique: use tools available for precise implant calculation; need to be familiar with toric calculator
(uses vector analysis to take into account surgically induced astigmatism) and factor this in when determining
where to place axis of implant; can adjust incision size and placement to reduce cylinder to zero; mark reference
0 and vertical and horizontal axes while patient sitting up; also place marks at limbus where incision
placed and where lens implanted; speaker recommends printing toric calculator and hanging on scope from
surgeon’s view; mark axis for incision and eye well placement, using Asico marker or Mendez ring; cataract
surgery routine, so make capsulotomy smaller than optic; put lens in when bag reinflated; leave implant
slightly short of desired axis because it may rotate somewhat when viscoelastic removed (difficult to reverse-
rotate lens); make final alignment; make sure lens dry before marking; line up ring with reference marks; look
at desired axis and identify vessel underneath it; remove ring and mark vessel; lens goes into bag, then rotate
lens to just shy of desired axis while viscoelastic removed; speaker prefers going underneath lens, holding it
with separate instrument to prevent it from rotating; viscoelastic removed from behind and front; use silicone
tip to rotate it around to almost perfect axis; speaker prefers to leave few degrees shy, hydrate incisions deep
in chamber, and make final touches with BSS cannula through side port
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| Summary: acrylic toric IOLs solve issues that previous designs had not; rotational stability good; toric calculator
useful tool; important to get lens at right axis to achieve high level of spectacle freedom
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Suggested Reading
Ahmed II et al: In-the-bag intraocular lens dislocation. Am Ophthalmol 139:952, 2005; Aslam TM et al: Effect
on glare of texturing the truncated edge of an intraocular lens. Arch Ophthalmol 121:1345, 2003; Baumeister M
et al: Tilt and decentration of three-piece foldable high-refractive silicone and hydrophobic acrylic intraocular
lenses with 6-mm optics in an intraindividual comparison. Am J Ophthalmol 140:1051, 2005; Olson RJ et al:
New intraocular lens technology. Am J Ophthalmol 140:709, 2005; Souza CE et al: Visual performance of
AcrySof ReSTOR apodized diffractive IOL: a prospective comparative trial. Am J Ophthalmol 141:827, 2006;
Whitehouse GM: The effect of cataract on Accumap multifocal objective perimetry. Am J Ophthalmol 136:209,
2003
Resources
www.doctor-hill.com
Educational Objectives
| The goal of this program is to improve patient selection, preoperative and postoperative management, and surgical
techniques of multifocal intraocular lens (IOLs) implantation. After hearing and assimilating this program, the clinician
will be better able to:
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| 1. Compare the technologies of various multifocal IOLs.
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| 2. Determine which patients are good candidates for multifocal IOL implantation.
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| 3. Educate patients to have realistic expectations about multifocal IOLs.
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| 4. Employ better work-up, surgical technique, and follow-up of patients for multifocal IOL implantation.
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| 5. Discuss the characteristics and surgical techniques for implanting toric IOLs.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose
relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any
identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a
proprietary business or commercial interest. For this program, the following has been disclosed: Dr. Cionni is a consultant
for AlconLabs and has a financial interest in Morcher GmbH.
Acknowledgements
Dr. Cionni was recorded at the 28th Annual Scientific Meeting, held February 23, 2007, in Salt Lake City, UT,
and sponsored by the Utah Ophthalmology Society. The Audio-Digest Foundation thanks Dr. Cionni and the
Utah Ophthalmology Society for their cooperation in the production of this program.
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