Retinal Imaging through Phakic Iris-Claw IOL

Abstract

Background: Phakic anterior chamber iris-fixated IOL (PIOL) are established for the correction of high myopia. These patients require attention to macular pathologies. This study was to evaluate the quality of imaging through the PIOLs. Methods: 54 eyes of 31 myopic and hyperopic patients with Verisyse®, Verisyse toric®, and Veriflex® phakic iris-fixated IOL were included. Mean preoperative refraction was ?11.0?D and +5.7?D, respectively; mean follow-up time was 7.4 years (5–11 years). A matched control group was formed without PIOL implantation. OCT scans were performed and evaluated qualitatively and quantitatively. Results: In 52 eyes of 31 patients (96%), a 3D-OCT image and fundus photo could be obtained in good quality. Foveal thickness was significantly thicker in the myopic patients, whereas all other sectors and total volume had no significant difference. Conclusions: It proved possible to obtain high-resolution scans and digital photos of the same quality as without additional phakic IOL.     

Phakic intraocular lenses

An analytical review of the data available in the field of phakic intraocular lens implantation was conducted. Particular attention was paid to the more critical issues of intraocular lens sizing and safety guidelines. A comprehensive, competitive analysis of different implantation sites, intraocular lens model designs, and safety guidelines has been included. Specialized biometry techniques, such as very high frequency ultrasound and Scheimpflug imaging, have been reviewed, and a critical review of commercial claims regarding intraocular lens technologies has been included. Clinical studies of phakic intraocular lenses demonstrate increasing promise for the correction of refractive errors not amenable to mainstream excimer laser refractive surgery. The main issues currently revolve around adequate lens design (VHF ultrasound study suggests that custom-design and sizing may be the most effective and safest approach for every phakic IOL model), because these devices will be required to remain physiologically inert and anatomically compatible with internal ocular structures and relations for several decades. The possibility of safe removing or exchanging the IOL should remain a feasible option over time. It is of utmost importance that we continue to critically evaluate current encouraging short-term outcomes, which are being extrapolated to the longer term by ongoing high resolution imaging and monitoring of the anatomical and functional relations of implanted phakic IOLs.     

Phakic intraocular lenses

PURPOSE OF REVIEW: Laser in-situ keratomileusis has been tremendously successful in treating patients with mild and moderate ametropias. For patients with high degrees of refractive error, however, phakic intraocular lenses provide superior quality of vision without the risk of corneal ectasia. Early international results, as well as United States Food and Drug Administration clinical trials, have demonstrated the early safety and efficacy of phakic intraocular lenses. Nevertheless, long-term corneal endothelium cell density and crystalline lens clarity remain a concern. RECENT FINDINGS: Several new studies demonstrate the superior visual outcomes of phakic intraocular lenses over laser in-situ keratomileusis in patients with moderate and high myopia, particularly in the areas of visual quality and contrast sensitivity. New anterior segment imaging and measurement technologies have provided valuable information about in-vivo structure and function, with and without phakic lens implants. More is being learned about long-term endothelial cell stability and cataract formation, particularly in relation to implant positioning. New applications of phakic intraocular lenses in presbyopia and in other conditions are being explored. SUMMARY: Once plagued by complications and marginal outcomes, improved designs of phakic intraocular lenses are providing increasing safety and efficacy for the correction of severe ametropias. Long-term concerns with endothelial cell loss remain, but recent data suggest stabilization with time. Proper sizing and positioning are important and increasingly achievable with new imaging modalities. With continued research and experience, phakic intraocular lenses are becoming an invaluable addition to the mainstream refractive surgery armamentarium.     

Bilateral Phakic Retinal Detachment

Ninety-nine (11.6%) of 850 phakic retinal detachment patients had bilateral detachments. The incidence of bilaterality was greater in nontraumatic detachments (13.4%) than traumatic detachments (3.8%). Patients were divided into two refractive classes: (1) myopic, containing refractive errors of ?2.50 diopters or more, and (2) nonmyopic, containing all other refractive errors. The rate of bilaterality in nontraumatic detachments varied with refractive class and lattice degeneration: nonmyopic without lattice (8.1%), nonmyopic with lattice (14.2%), myopic without lattice (16.3%), and myopic with lattice (24.6%). Mean age in years at onset of the initial detachment varied with refractive class and lattice degeneration: nonmyopic without lattice (59.1), nonmyopic with lattice (55.8), myopic without lattice (49.2), and myopic with lattice (28.2). Lattice degeneration reduced the interval between detachments. Annual risks of fellow eye detachments were calculated for four groups: nonmyopic without lattice (0.12%), nonmyopic with lattice (0.95%), myopic without lattice (1.3%), and myopic with lattice (0.98%).     

Phakic intraocular lenses.

Since Zaldivar's review of phakic intraocular lenses in these pages in 2000 [1**], further reports of experience with this technology have emerged. Their relative advantages and disadvantages over competing technologies are becoming clearer. Clinical trials, including Food & Drug Administration (FDA) trials, have shown predictability, stability, and efficacy. Safety of these implants over the long term remains a concern, but in some situations, at least, phakic intraocular lenses are becoming the refractive correction of choice. This brief review looks at the most recent data to emerge regarding phakic intraocular lenses.