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Phakic Intraocular Lenses Part 2: Results and Complications

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Phakic Intraocular Lenses Part 2: Results and Complications REVIEW/UPDATE Phakic intraocular lenses Part 2: Results and complications Thomas Kohnen, MD, PhD, FEBO, Daniel Kook, MD, Merce Morral, MD, Jose Luis Guell,€ MD The second part of a review of phakic intraocular lenses (pIOLs) addresses results and complica- tions with current pIOL models. Phakic IOLs demonstrate reversibility, high optical quality, poten- tial gain in visual acuity in myopic patients due to retinal magnification; correction is not limited by corneal thickness or topography. With proper anatomical conditions, pIOLs also show good results in hyperopic patients. Toric pIOL designs enable spherocylindrical correction. Complica- tions are rare and primarily related to pIOL position and type. The main complications of angle- supported anterior chamber pIOLs are glare and halos, pupil ovalization, and corneal endothelial cell loss; of iris-fixated anterior chamber pIOLs, chronic subclinical inflammation, corneal endo- thelial cell loss, and dislocation or pupillary block glaucoma; and of posterior chamber pIOLs, anterior subcapsular cataract formation, pigment dispersion, and luxation or pupillary block glau- coma. No causative relationship between pIOL implantation (of any pIOL type) and retinal detach- ment has been established. Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned. J Cataract Refract Surg 2010; 36:2168–2194 Q 2010 ASCRS and ESCRS Implantation of intraocular lenses in the phakic eye been on the market for some time. This second part (pIOL) is a relatively new technique to correct high of the pIOL review reassesses the published data ametropia. Time between the introduction of new about results and complications of currently available pIOL designs is short; thus, experience with a new pIOLs. The results of pIOLs that have been withdrawn pIOL is short when the pIOL is implanted. New pIOLs from the market are not discussed. As in Part 1,1 re- are presented to overcome specific complications of sults and complications are shown for each type of older pIOLs. Currently, many studies with short pIOL: angle-supported anterior chamber, iris-fixated follow-up and various case reports addressing results anterior chamber, and posterior chamber. and complications of pIOLs have been published, but Journal articles were considered for this review there are few long-term studies of pIOLs that have article after a thorough literature search. A Medline (National Library of Medicine, Bethesda, Maryland, USA) search from 1994 to 2009 was performed to iden- tify all articles describing pIOLs. The terms intraocular Submitted: March 25, 2010. lens and intraocular lens implantation from the Medical Final revision submitted: September 1, 2010. Subject Headings (MeSH) and the text word “phakic” Accepted: September 1, 2010. were used for a broad and sensitive search. Five other From the Department of Ophthalmology (Kohnen, Kook), Goethe- searches were performed to look for additional articles University, Frankfurt am Main, the Department of Ophthalmology (using the text words “phakic” and “lens,”“phakic” (Kook), Ludwig-Maximilians University, Munchen,€ Germany; Cullen and “IOL,”“anterior chamber lens,”“iris fixated Eye Institute (Kohnen), Baylor College of Medicine, Houston, Texas, lens,” and “posterior chamber lens.” All abstracts USA; Instituto Microcirugia Ocular (Morral, Guell),€ Institut Clinic from the Medline search were read to identify articles d’Oftalmologia (Morral), Hospital Clinic i Provincial de Barcelona, that were pertinent to clinical results, surgical tech- € and Autonoma University of Barcelona (Guell), Barcelona, Spain. niques, or complications of anterior chamber, iris- Corresponding author: Thomas Kohnen, MD, PhD, FEBO, Depart- fixated, and posterior chamber pIOLs. Copies of the ment of Ophthalmology, Goethe-University, Theodor-Stern-Kai 7, articles were obtained and the bibliographies searched 60590 Frankfurt am Main, Germany. E-mail: [email protected] manually for additional articles published in peer- frankfurt.de. reviewed journals. Complete articles were reviewed 2168 Q 2010 ASCRS and ESCRS 0886-3350/$ - see front matter Published by Elsevier Inc. doi:10.1016/j.jcrs.2010.10.007 REVIEW/UPDATE: PHAKIC INTRAOCULAR LENSES, PART 2 2169 to identify those that reported original clinical data or complication rate.41 In a prospective study comparing complication(s) of pIOLs. Articles that covered previ- matched populations of laser in situ keratomileusis ously published cases were included if they added (LASIK) and Visian ICL implantation, the ICL per- new cases or up-to-date results. formed better than LASIK in almost all measures of safety, efficacy, predictability, and stability.54 In FUNCTIONAL RESULTS OF pIOLs a few case reports, results with the toric posterior chamber pIOL have been shown.59,68,69 Schallhorn To provide an overview, results of published data for et al.56 report better results with the toric ICL than the pIOL types are shown in Tables 1 to 3. with conventional photorefractive keratectomy in a randomized prospective comparison of safety, effi- Results of Angle-Supported Anterior Chamber pIOLs cacy, predictability, and stability. Visual acuity, predictability, efficacy, and safety of In summary, pIOLs show good refractive and clini- the Baikoff ZB5M (Domilens Corp.), Kelman Duet cal results. They demonstrate reversibility, high opti- ZSAL-4 (Tekia, Inc.), I-Care (Corneal Laboratories, cal quality, potential gain in visual acuity in myopic Inc.), Vivarte (Ioltech), and AcrySof Cachet (Alcon, patients due to retinal magnification, and correction – Inc.) pIOL models are shown in Table 1.2 11 For the is not limited by corneal thickness or topography. Vivarte pIOL, results of only the refractive bifocal With proper anatomical conditions (especially suffi- Vivarte pIOL are included.10 At the time this review cient anterior chamber depth [ACD]), pIOLs also was written, no peer-reviewed studies of the Thin- show good refractive and clinical results in hyperopic PhAc (Thin Opt-X) and Vision Membrane (Vision patients.70 Phakic IOLs preserve corneal architecture, Membrane Technology) pIOLs had been published. asphericity, and accommodation. With recent innova- Despite the long period in which anterior chamber tions in the design of toric pIOLs, spherocylindrical pIOLs have been available, few long-term studies ex- correction is also feasible. However, pIOL implanta- ist.3,4 Anterior chamber pIOLs generally demonstrate tion is not without complications. The spectrum of good predictability, efficacy, and safety. However, common and rare complications with each type of there is a tendency toward undercorrection of the re- pIOL is presented in the following section. fractive error. Results of Iris-Fixated Anterior Chamber pIOLs COMPLICATIONS OF pIOLS Visual acuity, predictability, efficacy, and safety of General Complications of Intraocular Surgery the Artisan (Ophtec BV)/Verisyse (Abbott Medical With the increasing use of topical or parabulbar Optics, Inc.), toric Artisan/Verisyse, and Artiflex/ anesthesia, complications due to anesthesia such as Veriflex iris-fixated anterior chamber pIOL models retrobulbar hemorrhage, penetration of the globe, or – are shown in Table 2.9,12 39 Several studies have long life-threatening systemic side effects from accidental follow-up. The nontoric and toric models demonstrate injection into the optic nerve are very rare. Because good predictability, efficacy, and safety. With the implantation of a pIOL is an intraocular procedure, toric pIOL models, larger amount of preoperative it bears a potential risk for the development of post- astigmatism can be managed successfully. Several operative endophthalmitis. The risk for this complica- studies address clinical outcome after toric pIOL tion in general cataract surgery with implantation of implantation.27,30,36,37,39 Recently, Guell€ et al.27 re- a posterior chamber IOL is 0.1% to 0.7% with an op- ported a larger series with a mean follow-up of 3 years timal antiseptic perioperative treatment regimen.71 after implantation of the toric Artisan pIOL. The toric Recently, a prospective randomized multicenter Artiflex is currently undergoing a multicenter clinical study by the European Society of Cataract and Re- trial; it has shown excellent interim efficacy and safety fractive Surgeons72 showed that an additional intra- results in the first 6 months of follow-up. cameral application of cefuroxime after cataract surgery significantly reduced the rate of postopera- Results of Posterior Chamber pIOLs tive endophthalmitis. Only one case of postoperative Visual acuity, predictability, efficacy, and safety of endophthalmitis after pIOL implantation has been the implantable Collamer Lens (ICL) (Staar Surgical reported.73 In this case, endophthalmitis developed Co.) and the Phakic Refractive Lens (PRL) (Carl Zeiss on the first day after anterior chamber pIOL implan- Meditec) posterior chamber pIOL models are shown tation and was caused by b-hemolytic streptococci. – in Table 3.3,18,33,40 67 The safety and efficacy of these Intraoperative sterility and meticulous postoperative 2 pIOL models are good. In a United States Food follow-up examinations may help prevent this severe and Drug Administration (FDA) study, the ICL pIOL complication or enable early and aggressive showed good functional results with a low treatment. J CATARACT REFRACT SURG - VOL 36, DECEMBER 2010 2170 REVIEW/UPDATE: PHAKIC INTRAOCULAR LENSES, PART 2 Table 1. Visual acuity, predictability, efficacy, and
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