CATARACT/FLUOROQUINOLONES
| LENS-BASED REFRACTIVE SURGERY —Robert P. Lehmann, MD, Clinical Associate Professor of Ophthalmology,
Baylor College of Medicine, Houston, TX
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| Patient satisfaction with new technologies depends on: patient examination and education (critical); accurate biometry
and keratometry; intraocular lens (IOL) calculations (must be current); IOL selection based on patient’s needs; preoperative
care similar to that for refractive patient (dry eye needs attention)
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| Successful lens calculation: compounding of small errors can lead to larger errors; lawsuits settled in plaintiff’s favor
with result of -1 diopter (D) refractive error because patient was not informed that that could occur
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| Instrumentation: speaker routinely employs immersion A-scan biometry; IOL Master led to improved predictability
of results; avoid taking keratometric (K) readings after placing drying agent, eg, proparacaine (Ophthaine), in eye; discontinue
contact lens wear for sufficient period before performing keratometry
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| Lens position and postoperative refraction: in myopes, slightly less disparity in outcome; in hyperopes, 1-mm
error in axial length measurement can lead to 2.5-D error in postoperative outcome
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| Formulation and customization of IOL calculation: important to use new-generation methods (SRKT or Holladay
II); if using another formula, customize A-constant, anterior chamber depth, and surgeon factor, based on postoperative
outcomes; need for regular calibration of instrumentation often overlooked; compare bilateral
measurements, calculate using modern formulas, then customize
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| Successful lens implantation: depends on proper patient selection and education, realistic expectations, and accurate
biometry and power calculations; cornerstone of successful high-tech lens implantation education of patient and
surgeon (both need to understand what lens can do); “undersell and overdeliver”; be prepared to correct ametropias
(but it may not require lens exchange; surprise to physician may be pleasure to patient)
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| Targeting emmetropia: based on patient preferences and desires; use new-generation formula; customize A-constant
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| Yellow lenses: debated in literature; Hoya lens in Food and Drug Administration (FDA) study (premarket approval
expected in near future); trend nationally and internationally
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 | Tecnis IOL: recently approved; studies looked at contrast sensitivity and driving tests
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| AcrySof IQ IOL (SN60WF; Alcon): more recently approved; in driving simulation, patients had enhanced performance
with aspheric lens; reduction of higher-order aberrations, compared to control group that received AcrySof SA60 IOL;
compensation strategy for spherical aberration should restore negative spherical aberration (ie, negative spherical
aberration provided by human crystalline lens) in order to counteract positive spherical aberration of cornea (decentration
problem in these patients); when lens removed, loss of some positive spherical aberration can be added back
with lens implant to create lens that gives less spherical aberration and enhances contrast sensitivity for, eg, low illumination
and night driving; AcrySof IQ lens adds 0.2 negative spherical aberration for 6-mm pupil; if pupil 2.0 or
2.5 mm, no benefit (as pupil enlarges, asphericity imparts greater advantage); reduced optical center thickness,
which allows insertion of lens through incision of 2 mm (in most cases, speaker uses 2.7 mm using diamond
blades); New Technology Intraocular Lens (NTIOL) status granted by Centers for Medicare and Medicaid Services
(CMS) this year (Tecnis first); adds 0.27 negative spherical aberration for 6-mm pupil and Bausch & Lomb (B & L)
adds no negative spherical aberration for 6-mm pupil; design prevents induced aberrations with decentration and
tilt; AcrySof IQ thinnest lens of group (can be inserted through smaller incision)
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| Toric IOLs (overview): speaker performs limbal-relaxing incisions when cylinder ≥1 D; consider temporal incision; for
with-the-rule astigmatism of 1.0 to 2.0 D, approach relatively accurate; managing astigmatism at time of cataract surgery
with limbal-relaxing incisions almost “like throwing darts” (for 1 D cylinder, surgeon closer to board; for ≥2.5 D, surgeon
farther away); even laser-assisted in situ keratomileusis (LASIK) or photorefractive keratoplasty (PRK) has drawbacks
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| Description: single-piece platform; posterior surface toricity; same dimensions as other series of AcrySof single-piece
lenses; goes through Monarch II B or C cartridge; standard edge design; 3 powers (T3, T4, and T5); correcting 1.5,
2.25, or 3.0 D cylinder
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| Clinical study: randomized prospective FDA study; ≈500 subjects with control group; clinical rotation—mean rotation
<4°; Staar silicone IOL first toric lens premarket approved (lacked adherence to capsular bag; problem of rotation);
AcrySof single-piece IOL most likely will stay in place; residual refractive error—patients 3 times more
likely to achieve <0.5 D residual refractive cylinder than control group; excellent clinical results in FDA study; uncorrected
distance vision—94% of toric lens patients 20/40 or better; statistically significant improvement over
control (spherical lens) group; distance-vision spectacle freedom—almost 60% with unilateral implantation (97%
with bilateral); summary—excellent rotational stability; reduced residual refractive cylinder; significantly improved
spectacle freedom
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| Learning curve: mark patient preoperatively, then when on table; mark patient at slit lamp when seated (significant
percentage of excyclorotation when patients lie down); initially, gross alignment, removal of viscoelastic, then final
alignment; lens tends to turn clockwise (stop slightly short of mark, then remove viscoelastic)
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| Cataract patient as refractive patient: important to manage blepharitis/dry eye; speaker treats cataract patients
with 4th-generation fluoroquinolones (in LASIK patients, acetazolamide [Diamox] and gatifloxacin [Zymar]); 2 days
before surgery, cataract patients started on nepafenac (Nevanac); with routine administration of nonsteroidal anti-inflammatory
drugs (NSAIDs), reduced incidence of cystoid macular edema (CME)
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| Surgical tips: if patient has minimal nuclear opacity (1+) and significant posterior subcapsular cataract (PSC), or comes
in for refractive lens exchange, main procedure AquaLase; otherwise, speaker routinely employs torsional phacoemulsification;
polish posterior capsule; if tip worn, possible to tear capsule; make capsulorrhexis round (5.0-5.5 mm) so that it
overlies optic of lens; centering of rhexis over implant and covering periphery of lens reduces risk for capsular opacification;
remove viscoelastic from behind lens (speaker uses DisCoVisc routinely); seat and center lens, using single-piece
AcrySof Natural (IQ in standard patients; if patients desire greater spectacle independence, AcrySof ReStor IOL); avoid
aspheric lens for patient who has had hyperopic LASIK ablation (adds too much plus asphericity); speaker uses AcrySof
IQ IOL routinely in pilots (not AcrySof ReStor lens)
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| Toxic anterior segment syndrome (TASS)
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| Signs and symptoms: blurry vision; pain may be present; in past, cardinal sign of endophthalmitis pain (today, chief
presenting sign decreased vision); typically presents sooner than endophthalmitis; responds well to steroids; significant
trabecular meshwork damage and secondary glaucoma (difficult to control)
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| Potential etiologies: abnormalities of pH or ionic composition; abnormal osmolarity; particulate contamination; benzalkonium
(BAK), bisulfite in epinephrine, and edetate (EDTA); acetylcholine (Miochol), carbachol (Miostat), or miotics;
antibiotics in irrigating solution; intracameral antibiotics; instruments (eg, cannulas) not purged of viscoelastic;
endotoxin contamination; intraocular irrigating solutions (Balanced Salt Solution, BSS, Cytosol, Endosol); detergents
and enzyme residues used in cleansing instruments (ethylene oxide residue); particulate contaminants (talc, titanium,
fibers, and rubber bottle stoppers); polishing compounds on lens; topical medications (including ointments)
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| Diagnosis: perform thorough anterior segment examination; analyze surgical procedure
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| Treatment: intense topical corticosteroids (maximize penetration); shake prednisolone bottle well; administer 3 drops
at 30-sec intervals, every 30 min; close follow-up (speaker sees patients day 1 after surgery)
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| Clinical course: ranges from rapid clearing to more prolonged course; complications—chronic macular or corneal
edema possible (requires penetrating keratoplasty); iris atrophy in fixed dilated pupil with secondary glaucoma
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| Summary: TASS rare but devastating postoperative problem; awareness of etiology, analysis of possible causes, and
rapid treatment critical
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| FLUOROQUINOLONES: A CRITICAL REVIEW OF THE LITERATURE —David A. Hollander, MD, Associate
Physician Diplomate, Jules Stein Eye Institute, David Geffen School of Medicine at the University of California, Los
Angeles
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| Focus of discussion: 4th-generation fluoroquinolones (moxifloxacin [Vigamox]) and gatifloxacin [Zymar]); older
generation—ciprofloxacin and ofloxacin
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| Goals of newer fluoroquinolones: increased gram-positive coverage; increased drug delivery to anterior chamber;
potentially increased activity against atypical Mycobacterium; reduced likelihood of selecting resistance
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| Activity: targeting DNA synthesis at 2 sites (newer fluoroquinolones have better coverage, reducing likelihood of resistant
mutations)
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| Components: overall concentration (Vigamox 0.5%; gatifloxacin 0.3%); pH slightly different; Zymar contains preservative
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| Indications: approved by FDA for treatment of bacterial conjunctivitis; off-label use—common; cataract prophylaxis;
treatment of corneal ulcers; wound healing; Mycobacterium infection; newer infection patterns
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| Potency: susceptibility has little meaning in ophthalmology (serum concentration often different from ocular concentration);
minimum inhibitory concentration (MIC)—dose required to kill 50% of isolates; gram-positive organisms,
moxifloxacin lowest MIC (“most potent”); gram-negative organisms (ciprofloxacin and gatifloxacin superior)
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| Penetration: rabbit models—moxifloxacin achieves slightly higher concentration than gatifloxacin under different regimens
of q15-min dosing and qid dosing; at qid dosing, concentrations do not always reach MIC90 covering Staphylococcus
epidermidis (target for surgical prophylaxis); human studies (topical use for cataract prophylaxis)—3 days
preoperative use and same-day use; moxifloxacin better than gatifloxacin and far superior to ciprofloxacin in aqueous humor
ocular concentration; moxifloxacin (1-day prophylaxis; 30 times greater MIC than most common gram-positive
agents); vitreous levels—under intensive dosing regimens, topical formulations not achieving therapeutic intravitreal levels;
conjunctival concentrations—moxifloxacin far greater than gatifloxacin
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| Endophthalmitis: typically stems from flora on surface (conjunctiva, lid, or nose); study—newer fluoroquinolones
“great” at covering normal conjunctival flora; limited evidence in literature about endophthalmitis prophylaxis;
study—despite use of intracameral moxifloxacin or vancomycin, vitreous cultures remain positive and anterior
chamber cultures remain negative
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| Corneal ulcers and Fusarium: rabbit studies—for gram-negative pathogens, newer fluoroquinolones fared well,
compared to ciprofloxacin (for gram-positive coverage, they compare well with vancomycin); gatifloxacin vs
ciprofloxacin (in vivo model)—gatifloxacin did better against gram-positive cocci; no difference in activity against
gram-negatives
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| BAK-related issues: Zymar contains preservative (Vigamox does not)
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| Toxicity: under various dosing regimens, no great difference in corneal epithelial toxicity
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| Contamination (study): 61 bottles of moxifloxacin used perioperatively; single positive culture result from thread
(other components negative); suggests that lack of preservative not leading to contamination
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| Wound healing: PRK—moxifloxacin-treated patients undergoing photorefractive keratoplasty (PRK) may heal faster
than with gatifloxacin; however, at day 5 and 6 postoperatively, no significant difference (some benefit at day 4);
for LASIK and laser epithelial keratomileusis (LASEK)—safety and efficacy comparable; penetrating keratoplasty
(PK)—after 7 days, no difference in healing
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| Mycobacterium infection after LASIK: rabbit model—gatifloxacin alone and combined with amikacin and
clarithromycin may have slightly better efficacy than clarithromycin alone; Brazilian study (rabbit model)—17 of 18
LASIK-related infections resistant to gatifloxacin and moxifloxacin; gatifloxacin group fared better, but not infection
free
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| Summary: moxifloxacin more potent in vitro and achieves greater penetration; in surgical prophylaxis, both agents
cover conjunctival flora well (in rabbit models, effective for managing gram-positive and gram-negative keratitis);
both agents safe; insufficient evidence that one medication heals faster than other; “jury still out” on mycobacterial
prophylaxis; both medications have good spectrum of coverage and penetrate anterior chamber well; in future—fifth-
generation fluoroquinolones may better target Fusarium
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Educational Objectives
| The goal of this program is to educate the listener about lens-based refractive surgery and fluoroquinolones. After
hearing and assimilating this program, the clinician will be better able to:
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| 1. Educate patients about intraocular lens (IOL) implantation.
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| 2. Describe recent advances in IOL technology.
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| 3. Describe specific surgical strategies for improving outcomes after IOL implantation.
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| 4. Diagnose and manage toxic anterior segment syndrome.
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| 5. Assess the safety and efficacy of selected fourth-generation fluoroquinolones.
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Discussed on This Program
Acetazolamide [Dazamide, Diamox, Diamox Sequels]
Acetylcholine chloride, intraocular [Miochol-E]
Amikacin sulfate [Amikin]
Benzalkonium chloride (BAK) [Benza, Mycocide NS, no more germies towelettes, Ony-Clear, Zephiran]
Carbachol, intraocular [Carbastat, Miostat]
Ciprofloxacin [Ciloxan, Cipro, Cipro I.V., Cipro XR, Proquin XR]
Clarithromycin [Biaxin, Biaxin XL]
Edetate disodium (ethylenediaminetetraacetate; EDTA) [Endrate]
Epinephrine [Adrenalin Chloride, Adrenalin Chloride Solution, Epifrin, EpiPen, EpiPen Jr., Glaucon, microNefrin,
Nephron, Primatene Mist, S2]
Gatifloxacin [Tequin, Zymar]
Moxifloxacin HCl [Avelox, Avelox I.V., Vigamox]
Nepafenac ophthalmic suspension 0.1% [Nevanac]
Ofloxacin [Floxin, Floxin Otic, Ocuflox Ophthalmic Solution]
Proparacaine hydrochloride [Alcaine, Ophthaine, Ophthetic]
Sodium chloride, potassium chloride, magnesium chloride, calcium chloride, sodium acetate [AMO Endosol,
Balanced Salt Solution, BSS, Cytosol, Iocare Balanced Salt]
Vancomycin [Vancocin, Vancoled]
Resources
“Don’t lose your patients on the phone”. 19 min (American Media; West Des Moines, Iowa) 1987.
Suggested Reading
Al-Swailem SA, Al-Rajhi AA: Decentration and cataract formatio.10 years following posterior chamber silicone
phakic intraocular lens implantation. J Refract Surg 22:513, 2006; Baykara M: Techniques of intraocular lens suspension
in the absence of capsular/zonular support. Surv Ophthalmol 51:288, 2006; Callegan MC et al: Antibacterial
activity of the fourth-generation fluoroquinolones gatifloxacin and moxifloxacin against ocular pathogens. Adv Ther
20:246, 2003; Camellin M, Calossi A: A new formula for intraocular lens power calculation after refractive corneal
surgery. J Refract Surg 22:187, 2006; Donnenfeld E et al: A comparison of the fourth-generation fluoroquinolones
gatifloxacin 0.3% and moxifloxacin 0.5% in terms of ocular tolerability. Curr Med Res Opin 20:1753, 2004; Hollander
DA, Aldave AJ: Drug-induced corneal complications. Curr Opin Ophthalmol 15:541, 2004; Kashiwagi K
et al: Effects of small-incision phacoemulsification and intraocular lens implantation on anterior chamber depth and intraocular
pressure. J Glaucoma 15:103, 2006; Mah FS: Fourth-generation fluoroquinolones: new topical agents in the
war on ocular bacterial infections. Curr Opin Ophthalmol 15:316, 2004; Marshall J et al: Clinical results of the blue-
light filtering AcrySof Natural foldable acrylic intraocular lens. J Cataract Refract Surg 31:2319, 2005; Olson MD,
Miller KM: Implanting a clear intraocular lens in one eye and a yellow lens in the other eye: a case series. Am J Ophthalmol
141:957, 2006; Packer M et al: Refractive lens surgery. Ophthalmol Clin North Am 19:77, 2006; Savini G
et al: Intraocular lens power calculation after myopic refractive surgery: theoretical comparison of different methods.
Ophthalmology 113:1271, 2006.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue,
Dr. Lehmann disclosed that he has been a consultant for Alcon Laboratories and Advanced Vision Sciences.
Dr. Lehmann was recorded at the 2006 Regional Roundup presented July 19-22, 2006, in Whitefish, MT, by the State
Ophthalmological Societies of Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, North Dakota, South Dakota,
Utah, and Wyoming; Dr. Hollander was recorded at the Jules Stein Eye Institute Clinical and Research Seminar
, presented May 19-20, 2006, by the Jules Stein Eye Institute, Los Angeles, California, and the Doheny Eye
Institute, in Los Angeles, CA. The Audio-Digest Foundation thanks Drs. Lehmann and Hollander and the sponsors
for their cooperation in the production of this program.
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