Phakic refractive lens experience in Spain

A posterior chamber phakic refractive lens dislocated into the vitreous

SIGNIFICANCE

We present a unique cause for zonular dehiscence, which provides a pathway for subsequent dislocation of an implanted phakic refractive lens (PRL) into the vitreous cavity.

PURPOSE

To determine the cause of zonular dehiscence and to avoid similar complications after PRL implantation in the future.

CASE REPORT

A 37-year-old highly myopic patient with refraction of -24.0 DS in both eyes received PRL implantation in both eyes. In the 14-month postoperative follow-up, it was found that the PRL dislocated into the vitreous cavity. The patient then underwent phacoemulsification and vitrectomy. The patient was treated successfully. No ocular complication was found. The visual acuity of the left eye was 20/40, two weeks after surgery.

CONCLUSIONS

We report a unique cause for zonular dehiscence, and the clarification of its detailed characteristics may contribute to prevention of such a complication in the future.

Phakic intraocular lenses: An overview

Phakic intraocular lenses (pIOLs) are a common solution for the surgical correction of high myopia and myopia in thin corneas. Global trends result in increasing rates of patients with high myopia which will result in increased rates of pIOL implantation. Three types of lenses can be distinguished: anterior chamber angle-supported, anterior chamber iris-fixated, and posterior chamber phakic IOLs. The efficacy of phakic intraocular lenses is generally very good, but pIOLs have undergone many changes over the years to improve the safety profile and decrease pIOL-related complications such as endothelial cell loss, corneal decompensation and cataract formation. This article describes the efficacy and safety profiles of the most recent pIOLs, as well as suggests gaps of knowledge that are deserve additional research to optimize the results of pIOLs.

Phakic intraocular lens implantation for the correction of hyperopia

The prevalence of myopia is much higher than hyperopia. Hence, there are relatively few studies investigating phakic intraocular lens (pIOL) implantation for the correction of hyperopia. This review aimed to summarize the available relevant literature on the efficacy and safety of pIOL implantation for the correction of hyperopia and hyperopic astigmatism. At present, two types of pIOLs are used to correct hyperopia and hyperopic astigmatism: anterior chamber iris-fixated pIOLs and posterior chamber implantable collamer lenses. Both have been found to be safe and effective. No serious events (eg, retinal or choroidal detachment, endophthalmitis) were reported in the reviewed articles. Implantation of pIOLs might be the optimal refractive surgery for the correction of high hyperopia.

Acute Angle Closure Following Implantable Collamer Lens for Myopia

We report a case of acute angle closure with significantly elevated intraocular pressure 9 hours after implantation of a phakic intraocular lens for high myopia.

Clinical results of posterior chamber phakic intraocular lens implantation in eyes with low anterior chamber depth

PURPOSE

To investigate visual outcomes of Visian implantable Collamer lens (ICL) implantation in eyes with a shallow anterior chamber depth (ACD).

DESIGN

Retrospective, noncomparative, interventional case series.

METHODS

Medical charts of the patients with a low ACD of 2.8 mm or less who underwent implantable Collamer lens implantation were reviewed. To evaluate efficacy and safety, preoperative and postoperative uncorrected visual acuity, manifest refractive spherical equivalent (MRSE), endothelial cell count, intraocular pressure, angle opening distance at 500 μm from the scleral spur, trabecular-iris angle, and postoperative central vault were analyzed.

RESULTS

The mean follow-up period for 18 eyes of 10 patients was 24.67 ± 15.09 months (range, 10 to 51 months). The preoperative ACD was 2.71 ± 0.08 mm (range, 2.42 to 2.79 mm). There was no postoperative endothelial cell count reduction to less than 2000 cells/mm(2) or intraocular pressure elevation to more than 21 mm Hg. The differences between preoperative and postoperative angle opening distance at 500 μm from the scleral spur and trabecular-iris angle were statistically significant (P = .000, both). The mean postoperative central vault was 331.83 ± 181.28 μm (range, 174 to 811 μm), which was significantly less than expected (P = .000). Anterior subcapsular cataract was observed in 2 eyes (11.1%).

CONCLUSIONS

Implantable Collamer lens implantation in shallow ACD eyes exhibited good visual outcomes. Severe complications did not develop over relatively long periods. Two cases of anterior subcapsular cataract developed in older aged patients, suggesting the need for thorough preoperative warning about the risk of cataract. In addition, a postoperative vault less than expected should be taken into account when determining implantable Collamer lens size in lower ACD eyes.

Posterior chamber phakic intraocular lens to correct myopia: long-term follow-up

PURPOSE

To evaluate the long-term safety and efficacy of a refractive phakic intraocular lens (pIOL) (PRL) to correct moderate to high myopia.

SETTING

Department of Ophthalmology, University Medicine Charité Berlin, Berlin, Germany.

DESIGN

Retrospective cohort study.

METHODS

Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, intraocular pressure, endothelial cell loss, and adverse events were evaluated.

RESULTS

The study enrolled 53 eyes (mean spherical equivalent [SE] -12.17 diopters [D] ± 4.12 [SD]) of 29 patients. The mean age was 34.6 ± 9.2 years and the mean follow-up, 86 ± 21.2 months. The mean UDVA improved from 1.37 ± 0.28 logMAR preoperatively to 0.14 ± 0.19 logMAR at the last postoperative visit (P<.05). The mean CDVA improved from 0.10 ± 0.18 logMAR to -0.01 ± 0.09 logMAR (P<.05). The overall mean efficacy index and mean safety index were 0.9 and 1.21, respectively, at the last follow-up visit. The mean endothelial cell loss at the last follow-up was 6.4%. The complications were slight posterior chamber (PC) pIOL decentration (5 eyes, 9.4%), severe PC pIOL decentration resulting in pIOL removal (1 eye, 1.8%), glaucoma (4 eyes, 7.5%), clinically significant cortical lens opacification resulting in cataract surgery (4 eyes, 7.5%), clinically asymptomatic anterior subcapsular cataract formation (6 eyes, 11.3%), and retinal detachment (2 eyes, 3.8%).

CONCLUSIONS

Posterior chamber phakic pIOL implantation to correct moderate to high myopia provided predictable and stable refractive results but with a high rate of serious complications over the long term.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

The posterior chamber phakic refractive lens (PRL): a review

Implantation of phakic intraocular lenses (pIOLs) is a reversible refractive procedure, preserving the patient's accommodative function with minimal induction of higher order aberrations compared with corneal photoablative procedures. Despite this, as an intraocular procedure, it has potential risks such as cataracts, chronic uveitis, pupil ovalization, corneal endothelial cell loss, pigmentary dispersion syndrome, pupillary block glaucoma, astigmatism, or endophthalmitis. Currently, only two models of posterior chamber pIOLs are commercially available, the implantable collammer lens (STAAR Surgical Co.) and the phakic refractive lens (PRL; Zeiss Meditec). The number of published reports on the latter is very low, and some concerns still remain about its long-term safety. The present article reviews the published literature on the outcomes after PRL implantation in order to provide a general overview and evaluate its real potential as a surgical refractive option.

Preliminary in vivo positional analysis of a posterior chamber phakic intraocular lens by optical coherence tomography and its correlation with clinical outcomes

Purpose

To analyze by spectral-domain optical coherence tomography the anatomical relationship of a specific type of posterior chamber phakic intraocular lens (pIOL) implanted in cases of high to moderate myopia with the adjacent intraocular structures and to correlate it with clinical outcomes.

Methods

Prospective observational case series including 18 eyes with high to moderate myopia (spherical equivalent between −5.88 and −15.75 D) of 9 patients (age range, 29–49 years) undergoing bilateral Phakic Refractive Lens (PRL, Zeiss) implantation. Postoperative visual acuity, refraction, contrast sensitivity (CS), and ocular higher order aberrations (HOA) were evaluated. Furthermore, the in vivo position of the PRL was analyzed by means of spectral domain optical coherence tomography (3D OCT-1000, Topcon). Central (CENV), temporal (TEMV) and nasal vault (NASV) were measured. Correlation of these anatomical parameters with clinical data was also investigated. Mean follow-up was 47 ± 25 months.

Results

A statistically significant visual and refractive improvement (p < 0.01) was found postoperatively. Mean postoperative CENV, NASV, and TEMV were 157.88 ± 69.93 μm, 168.29 ± 65.02 μm, and 188.59 ± 55.99 μm, respectively. Significant difference was found between NASV and TEMV (p = 0.01). No significant correlations were found between ocular aberrometric and anatomical parameters (p ≥ 0.12). CENV, NASV and TEMV correlated significantly with 6-cycles per degree (cpd) photopic CS as well as with 18-cpd low mesopic CS (r ≥ 0.57, p ≤ 0.04). Furthermore, NASV also correlated significantly with preoperative anterior chamber depth (r = −0.65, p = 0.01).

Conclusions

This posterior chamber pIOL shows a trend to nasal position, with potential impact on refractive and visual outcomes, particularly in eyes with deep anterior chambers.

Medium-term visual, refractive, and intraocular stability after implantation of a posterior chamber phakic intraocular lens to correct moderate to high myopia

PURPOSE

To evaluate the medium-term refractive and visual outcomes and the complications after implantation of a silicone posterior chamber phakic intraocular lens (PC pIOL) for moderate to high myopia.

SETTING

Oftalmar, Medimar International Hospital, Alicante, Spain.

DESIGN

Retrospective case series.

METHODS

Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, and intraocular pressure were evaluated during a medium-term follow-up. Postoperative complications were also studied.

RESULTS

The study enrolled 35 eyes (mean preoperative spherical equivalent [SE] -10.25 diopters [D] ± 3.19 [SD]) of 20 patients with a mean age of 31.83 ± 8.87 years and a mean follow-up of 57.34 ± 9.24 months. The mean UDVA improved from 2.40 ± 0.20 logMAR preoperatively to 0.08 ± 0.13 logMAR at the last postoperative visit (P<.01). The mean CDVA improved from 0.11 ± 0.09 logMAR to 0.02 ± 0.09 logMAR, respectively (P<.01). The postoperative CDVA was 0.1 or better in 30 eyes (85.71%), with 22 eyes (62.86%) gaining lines of CDVA. The final efficacy index was 1.16 and the final safety index, 1.26. Regarding predictability, 34 eyes (97.14%) had an SE within ± 1.00 D and 33 eyes (94.28%) within ± 0.50 D. The complications were PC pIOL decentration (2 eyes, 5.71%), cortical lens opacification (1 eye, 2.86%), and retinal detachment (1 eye, 2.86%).

CONCLUSIONS

Implantation of a PC pIOL to correct moderate to high myopia was efficient and predictable in the medium term, with intraocular stability in most cases. New designs and criteria for PC pIOL size selection should be developed.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Retinal complications of phakic intraocular lenses

High myopia has always been a challenge for refractive correction. Current laser surgical techniques, however, fall short of correcting high refractive errors due to lack of predictability, regression, corneal ectasia, and introduction of high order optical aberration. Phakic intraocular lenses (IOL) have been proposed as an effective refractive surgical procedure for the correction of severe myopia, but, despite recent advances in implant material technology and design, their concept is still under clinical investigation. Most of the concern regarding the complications of phakic IOLs focuses on the anterior segment of the eye. This review examines the posterior segment complications associated with phakic IOL implantation, evaluates possible pathogenetic mechanisms and discusses posterior segment complications, prevention and management.

Optical Coherence Tomography of the Anterior Segment in Eyes with Phakic Refractive Lenses

PURPOSE

To evaluate the dynamics of the phakic refractive lens (PRL) in myopic and hyperopic eyes in the nonaccommodated state and during subjective accommodation with Visante optical coherence tomography (OCT).

DESIGN

Cross-sectional study.

PARTICIPANTS

Forty-one myopic eyes and 11 hyperopic eyes of 52 patients (mean age, 34 years; range, 24-49) were examined at least 1 year after PRL implantation using Visante OCT. Thirty-one myopic eyes had the PRL model 101 and 10 eyes had the smaller PRL model 100 implanted. The hyperopic model, PRL 200, is available in only one size.

METHODS

Noninvasive high-resolution anterior OCT was used to measure distance changes between the PRL and adjacent intraocular structures in the nonaccommodative state (baseline) and during accommodation.

MAIN OUTCOME MEASURES

Mean distance changes from the anterior lens surface (ALS) to the PRL and from the corneal posterior surface to the ALS and the PRL, and changes in the pupil diameter.

RESULTS

At baseline, the mean distances between the PRL and crystalline lens were 0.38, 0.30, and 0.32 mm for the PRL 101, PRL 100, and PRL 200, respectively. The PRLs were significantly closer to the crystalline lens with increasing patient age. Three PRLs were in contact with the crystalline lens (6%), and there were lens opacities in 2 of these eyes. During accommodation, the ALS of all PRL models showed significant forward movement (P<0.05), whereas the distance between the PRL and crystalline lens decreased significantly with the PRL 101 and PRL 200 (P<0.05). The distance between the PRL 100 and crystalline lens remained unchanged during accommodation.

CONCLUSION

The PRL moved forward during accommodation in all eyes, with the distance preserved between the PRL and the ALS with the PRL 100. The distance decreased with the other 2 models. In 85% of cases, there was no mechanical contact with the ALS during accommodation.

[Ultrasound biomicroscopy of posterior chamber phakic intraocular lenses: a comparative study between ICL and PRL models]

PURPOSE

To evaluate the anatomic relationships of the implantable contact lens (ICL) and the phakic refractive lens (PRL) posterior chamber phakic intraocular lenses (PCP IOL) using ultrasound biomicroscopy (UBM).

MATERIAL AND METHODS

Seventeen phakic myopic eyes corrected with ICL, and 14 phakic myopic eyes that had had PRL implantation, were examined retrospectively using UBM. The main parameters measured and compared were anterior chamber depth, central and peripheral distance between PCP IOL and the crystalline lens, and exact lens haptic position.

RESULTS

The mean distance between the PCP IOL and the central endothelium was 2398+/-203 microm and 2640+/-230 microm in the ICL and PRL groups, respectively. The central vault between the implant and the crystalline lens was greater in eyes with ICL (ICL, 402+/-194 microm; PRL, 256+/-187 microm, p<0.05). However, the incidence of lens contact on the peripheral level was higher in the ICL group (41%) than in the PRL group (29%), and the difference between the two implants in the peripheral crystalline lens-PCP IOL distance was significant (p<0.05). Both IOL haptics appeared to be correctly positioned in the sulcus in 13 (76%) eyes of the ICL group, and on the zonule in eight eyes (57%) of the PRL group.

CONCLUSIONS

PCP IOL implantation is a safe procedure for the correction of high myopia with regard to refractive results. UBM provides a unique tool to noninvasively evaluate the relations of these implants within the posterior chamber, and helps to analyze the mechanisms of crystalline lens and iris complications.

Évaluation de l’échographie 20 MHz CineScan® dans les mesures intra-oculaires

BACKGROUND AND OBJECTIVE

Evaluation of the Quantel Medical 20-MHz Ultrasound Cinescan using a closed transducer in intraocular measurements and its reproducibility.

PATIENTS AND METHODS

We measured sulcus-to-sulcus distance of 40 control eyes using the20-MHz Cinescan. Then we compared the sonography to the Oculus Pentacam based on the Scheimpflug principle in the measurements of anterior chamber depth, cornea-to-implant distance, and implant-to-crystallin lens distance in patients who underwent phakic implantation (56 eyes).

RESULTS

With this technique, the sulcus-to-sulcus distance can be measured with a reproducibility of 86%-88% (p<0.05). The authors show that the corneal diameter is not correlated with the sulcus measurement (R=24%, p<0.05).

DISCUSSION

Several techniques are used to quantify anterior segment biometry. Some of these methods, such as White-to-White, are too empirical and others, such as the Scheimpflug camera - for example the EAS-1000 (Nidek) - or high-frequency ultrasound - Ultrasound BioMicroscopy UBM P45 (Paradigm) - are too expensive. The 20-MHz Cinescan has good reproducibility and provides easier access to anterior segment biometry.

CONCLUSION

The 20-MHz Cinescan appears to be an accessible technique that may become a useful tool in the refractive surgery of the phakic intraocular lens.

Correction of high myopia with the PRL phakic intraocular lens

PURPOSE

To assess the predictability, efficacy, safety, and complications of the PRL (CIBA Vision) phakic intraocular lens (pIOL) in the correction of high myopia.

SETTING

Clínica Oftalmológica Pasteur, Santiago, Chile.

METHODS

This prospective study comprised 53 eyes of 39 patients who received a PRL pIOL. The spherical equivalent (SE), uncorrected visual acuity (UCVA), efficacy index (postoperative UCVA/preoperative best spectacle-corrected visual acuity [BSCVA]), safety index (BSCVA/preoperative BSCVA), intraocular pressure (IOP), iridocorneal angle, and distance between the crystalline lens and PRL were prospectively assessed during the follow-up period.

RESULTS

The mean patient age was 39 years. The mean power of the implanted pIOL was -12.73 diopters (D) +/- 2.87 (SD) (range -20.00 to -7.00 D), for a preoperative SE of -17.27 +/- 4.58 D (range -31.50 to -8.75 D). The mean preoperative BSCVA was 0.50 +/- 0.70 (logMAR equivalent), and the mean follow-up was 8 +/- 9.4 months. The mean postoperative SE was -0.23 +/- 1.05 D; 71.2% of eyes were within +/-1.00 D. Sixty percent of patients had UCVA of 20/40 or better, and 88.2% of patients had BSCVA of 20/40 or better. Ninety-two percent maintained or gained 1 or more lines of BSCVA; 5.7% lost more than 1 line. There was no significant change in IOP (P = .40), and the mean distance between the crystalline lens and pIOL was 370 microm (ultrasound) and 604 microm (optical coherence tomography). Late complications included 1 case each of retinal detachment and lens subluxation.

CONCLUSIONS

Although PRL implantation in high myopia was predictable and effective, retinal detachment and IOL subluxations occurred. Other posterior chamber pIOLs should be used until the complications associated with the PRL pIOL are resolved.

Cataractous Changes due to Posterior Chamber Flattening with a Posterior Chamber Phakic Intraocular Lens Secondary to the Administration of Pilocarpine

OBJECTIVE

To present the first reported case of cataract formation as a consequence of instillation of pilocarpine in an eye with a posterior chamber phakic intraocular lens (IOL).

DESIGN

Interventional case report.

INTERVENTION

A 46-year-old man received a hyperopic implantable collamer lens (ICL) bilaterally.

MAIN OUTCOME MEASURES

Determination of best-corrected visual acuity (BCVA); contrast sensitivity testing with and without glare; and intraocular pressure (IOP), specular endothelial cell, and slit-lamp examinations were performed serially. In addition, the distance between the ICL and crystalline lens was measured with optical coherence tomography.

RESULTS

Both eyes underwent uneventful ICL implantation for the correction of a manifest spherical equivalent of +7 diopters (D) in the right eye and +7.1 D in the left eye. The left eye was followed for 2 years without developing complications. The right eye, however, showed on the first postoperative day a fleckenlike opacification on the anterior pole of the crystalline lens after instillation on the operative day of 2% pilocarpine in an attempt to accelerate recovery from unwanted pupil dilation causing patient complaints of glare disability after surgery. Optical coherence tomography demonstrated complete contact of the ICL with the natural lens 24 hours postoperatively. Serial IOP measurements were always within the normal limits. The instillation of 1% cyclopentolate resulted in an increase in the ICL vault that measured 132 mum 24 hours later. Three days after the completion of a 3-day course of topical 1% cyclopentolate, the opacification was less dense and demarcated, and a 124-mum vault was measured. Three months postoperatively, the cataract was associated with a 3-line loss of BCVA and considerable degradation of the contrast sensitivity, especially at higher spatial frequencies and with a glare source, and corneal endothelial cell changes were within normal limits. One year after ICL implantation, the right eye had to undergo phacoemulsification and IOL implantation, which were uneventful.

CONCLUSIONS

Posterior chamber flattening with resulting crystalline lens opacification can occur immediately after the instillation of pilocarpine in an eye with a hyperopic ICL. Therefore, caution should be taken with the administration of cholinergic agonists such as pilocarpine in patients with phakic IOLs, at least if they are hyperopic ICLs.

Surgical Correction of Hyperopia

Surgical attempts to correct hyperopia have yielded varying results over the last 130 years. These techniques include the reshaping of the cornea through incisions, burns, or lamellar cuts with removal of peripheral tissue; the addition of central inlays; laser ablations; and the replacement of the crystalline lens. By examining the success of each surgical technique, the refractive surgeon may be able to make an informed decision on its indications and limitations, based on the specific patient's characteristics. Reporting the outcomes and complications of hyperopic surgery will help refine our approach to the management of an increasingly hyperopic and presbyopic population.

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.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses which are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for posterior chamber lenses these are mainly cataract formation and pigment dispersion. RLE is preferable in cases of high ametropia in which the natural lens has lost its accommodative effect. The main complications for myopic RLA include retinal detachment, while hyperopic refractive lens exchange may be associated with surgical problems in the narrower anterior eye segment.

Intraokularlinsen zur Korrektur von Refraktionsfehlern

In this overview, the current status of intraocular lens surgery to correct refractive error is reviewed. The interventions are divided into additive surgery with intraocular lens implantation without extraction of the crystalline lens (phakic intraocular lens, PIOL) or the removal of the crystalline lens with implantation of an IOL (refractive lens exchange, RLE). Phakic IOLs are constructed as angle-supported or iris-fixated anterior chamber lenses and posterior chamber lenses that are fixated in the ciliary sulcus. The implantation of phakic IOLs has been demonstrated to be an effective, safe, predictable and stable procedure to correct higher refractive errors. Complications are rare and differ for the three types of PIOL; for anterior chamber lenses these are mainly pupil ovalization and endothelial cell loss.

Angle-supported phakic intraocular lenses in hyperopia

PURPOSE

To evaluate the efficacy and safety of angle-supported phakic intraocular lenses (PIOLs) in hyperopia.

SETTING

Private practice, Siena, Italy.

METHODS

A prospective noncomparative single-surgeon interventional case series comprised 42 consecutive hyperopic eyes of 22 patients having implantation of a type PIOL (Morcher) through a sclero-corneal 5.5 mm x 3.0 mm tunnel along the steepest meridian, with surgical iridectomy. The mean preoperative defocus equivalent (DEQ) was 7.30 diopters (D) +/- 1.89 (SD). The mean spherical equivalent (SE) was 6.61 +/- 1.47 D (range 4.0 to 10.5 D), and the mean refractive astigmatism was 1.51 +/- 1.33 D (range 0 to 5 D). The mean age was 29.9 +/- 6.0 years (range 22 to 42 years). Thirteen patients (59%) were men.

RESULTS

Postoperative mean SE was 0.38 +/- 0.52 D (range 0 to 2 D); mean DEQ 0.93 +/- 0.98 D; mean astigmatism 0.95 +/- 1.17 D; mean surgically induced astigmatism (vector analysis) 0.67 +/- 0.58 D (95% confidence interval, 0.49-0.85); 38 eyes (90%) were within +/-2 D of DEQ, 34 eyes (81%) within +/-1 D, and 24 eyes (57%) within +/-0.5 D. Safety index was 1.05; efficacy index 0.85. Complications were night halos 10%; pupil ovalization 7%; pupillary block reversed by neodymium:YAG laser 7%; monocular anterior subcapsular opacity 5%; monocular iridocyclitis 5%; and intraocular pressure rise due to topical steroids 2%. Endothelial cell loss at 12 month was 6% (range +2.5% to -11%).

CONCLUSION

High hyperopia was corrected safely and predictably by an angle-supported PIOL with limited complications.

Clinical outcomes of phakic refractive lens in myopic and hyperopic eyes: 1-year results

PURPOSE

To confirm the safety, efficacy, and predictability of the surgical correction of myopia and hyperopia with the phakic refractive lens (PRL) (Medennium Inc.).

SETTING

St. Eriks Eye Hospital, Stockholm, Sweden.

METHODS

This was a prospective clinical study of 20 eyes, 14 myopic and 6 hyperopic, that had PRL implantation at St. Eriks Eye Hospital from April to November 2002. Examinations were performed preoperatively and 1 day, 1 week, 3 months, and 1 year postoperatively. Follow-up included evaluation of the PRL rotation with retroillumination photography, evaluation of the distance between the PRL and the crystalline lens with Scheimpflug image, laser flare, endothelial cell count, uncorrected (UCVA) and best corrected (BCVA) visual acuity, residual refractive error, refractive stability, intraocular pressure, and induced cataract.

RESULTS

Postoperatively, 11 eyes (55%) gained 1 or more lines, 5 eyes (25%) had no change, and 4 eyes (20%) lost 1 line of BCVA. No eye lost 2 or more lines. Mean UCVA was 0.87+/- 0.29 postoperatively. Laser flare values were highest 1 day after operation with normalization at 3 months and without changes at 1 year (P<.05). A rotation of 10 degrees or more was found in 15 eyes (75%) during the first year. The distance between the PRL and crystalline lens was considerably less at 1 year than at baseline (P<.05). There was no statistically significant endothelial cell loss induced by the PRL (P<.05). No induced cataract, glaucoma, or inflammation was observed. In 1 hyperopic eye, horizontal iris transillumination defects were noticed at 1 year.

CONCLUSION

Safety and efficacy indexes were high at 1-year follow-up. The PRL rotated slightly in the posterior chamber. The distance between the PRL and the crystalline lens was considerably less at 1 year than at baseline.

Contact entre le cristallin naturel et différents modèles d’implants réfractifs phakes. Étude avec l’OCT de chambre antérieure

Three patients received three different models of phakic implants. With the usual slit-lamp examination method, we were not able to establish whether there was contact between the implants and the natural crystalline lens. Using the anterior chamber optical coherence tomography scanner (AC-OCT), we were able to demonstrate that there was direct contact between the natural crystalline lens and the three different phakic implants. A dynamic study of these contacts was carried out during accommodation. These observations show that examination of the anterior segment with the optical coherence tomography scanner is essential in refractive surgery.

Changes in contrast sensitivity after Artisan lens implantation for high myopia

PURPOSE

To determine the effects of Artisan lens implantation on contrast sensitivity.

DESIGN

Prospective consecutive interventional case series.

PARTICIPANTS AND CONTROLS

Forty-nine eyes of 30 patients with myopia and myopia with astigmatism, who underwent implantation of the Artisan iris-fixated phakic intraocular lens. Preoperative testing served as the control.

INTERVENTION

Implantation of the Artisan phakic intraocular lens to correct myopia.

MAIN OUTCOME MEASURES

Refractive predictability and Snellen visual acuity were evaluated preoperatively and at least 4 months postoperatively. Additionally, photopic and mesopic contrast sensitivities were measured at 1.5, 3, 6, 12, and 18 cycles per degree, with and without glare testing.

RESULTS

The mean preoperative spherical equivalent (SE) was -12.16 diopters (D) (range, -6.88 to -18.00). The mean postoperative SE was -0.46+/-0.58 D (range, +0.50 to -1.75). Ninety percent of eyes were within 1.00 D of the predicted result, and 39% gained > or =1 lines of best-corrected visual acuity (BCVA). When compared with preoperative measurements, postoperative contrast sensitivity was increased under photopic conditions and slightly decreased under mesopic conditions. Adverse events were one wound leak requiring resuturing in the immediate postoperative period and one subluxed lens after significant blunt trauma. No eyes lost > or =2 lines of BCVA.

CONCLUSIONS

Artisan implantation for the correction of high myopia seems to be a predictable procedure. Increases in photopic contrast sensitivity values after implantation of this phakic intraocular lens stand in distinction to the decreases in photopic contrast sensitivity previously reported after LASIK correction of this degree of myopia.

Zonular Dehiscence Two Years After Phakic Refractive Lens (PRL) Implantation

PURPOSE

To report two cases of zonular dehiscence two years after phakic refractive lens (PRL) implantation.

METHODS

In case 1, a 31-year-old myopic patient with refraction of -12.75 diopters (D) in the right eye and -20.50 D in the left eye, a 12-mm white-to-white measurement, and anterior chamber depth (ACD) of 3.7 mm underwent implantation of a -11.0 D and a -15.5 D PRL-101. Two years after surgery, a temporal-superior PRL decentration was observed in the left eye. In case 2, a 48-year-old pseudophakic patient with refraction of +8 -2.5 x 20 degrees underwent implantation of a piggyback PRL-200. Two years after surgery, an inferior PRL decentration was observed.

RESULTS

The PRL was explanted in both cases. A zonular dehiscence was found--temporal-superior in case 1 and inferior in case 2.

CONCLUSIONS

We have stopped implanting PRLs for the present time as the cause of this complication has yet to be determined.

Spontaneous dislocation of a phakic refractive lens into the vitreous cavity

A 36-year-old woman with high myopia had uneventful implantation of a phakic refractive lens (PRL) bilaterally. Two months postoperatively, the best corrected visual acuity (BCVA) in the right eye decreased to the preoperative level and the posterior chamber PRL disappeared from the anterior segment and was found lying in the vitreous cavity inferiorly. After lensectomy and pars plana vitrectomy, the PRL was removed through the initial clear corneal incision, improving the BCVA to 1.0. A zonular defect associated with high myopia, previously forgotten and unrecognized ocular trauma, or intraoperative manipulations may have resulted in the spontaneous dislocation of the PRL.

Silicone Posterior Chamber Phakic Intraocular Lens Dislocated into the Vitreous Cavity

PURPOSE

To report two highly myopic patients with silicone posterior chamber phakic intraocular lenses (Phakic Refractive Lens; CIBA Vision, Duluth, Ga) that luxated into the vitreous cavity without history of ocular trauma.

METHODS

Two patients with posterior chamber phakic intraocular lenses (PIOLs) that luxated into the vitreous cavity of the right eye were examined. Each eye underwent pars plana vitrectomy and removal of the posterior chamber PIOL under retrobulbar anesthesia.

RESULTS

Both patients were treated successfully. In the first patient, the posterior chamber PIOL luxated into the anterior vitreous cavity whereas in the second patient, the posterior chamber PIOL lay on the posterior pole. No ocular complications developed postoperatively.

CONCLUSION

Luxation into the vitreous cavity is a rare, but potentially severe complication of posterior chamber PIOL refractive surgery in highly myopic eyes. Successful management includes pars plana vitrectomy and removal of the posterior chamber PIOL.

Ten-year follow-up of a ciliary sulcus-fixated silicone phakic posterior chamber intraocular lens

In 1992, a ciliary sulcus-fixated, silicone, phakic posterior chamber intraocular lens (PPC IOL) (Adatomed, Fyodorov type) was implanted in both eyes of a 42-year-old white woman to correct high myopia (right eye, -17.0 diopters [D]; left eye, -11.5 D). In the right eye, localized cortical opacification was present in the anterior part of the natural lens preoperatively but did not progress during a 10-year follow-up period. With Scheimpflug photography, it was possible to detect a space between the natural lens and the IOL that was not evident on slitlamp examination. Maintenance of space between an IOL and the natural lens appears to be an important factor in preventing cataract formation after PPC IOL implantation.

Contact between 3 phakic intraocular lens models and the crystalline lens: An anterior chamber optical coherence tomography study

Three phakic intraocular lens (IOL) models were implanted in 3 different patients. With the usual slitlamp examination, it was not possible to determine whether there was contact between the IOLs and the natural crystalline lens. Using the anterior chamber optical coherence tomography (AC OCT) scanner, direct contact between the natural crystalline lens and the 3 phakic IOLs was revealed. A dynamic study of the contact was performed during accommodation. These observations show that examination of the anterior segment with the AC OCT scanner provides new data about the status of the anterior segment after implantation of phakic IOLs.

Phakic refractive lens implantation in high myopic patients: one-year results

PURPOSE

To evaluate the efficacy and safety of implantation of a new posterior chamber phakic refractive lens (PRL, Ciba Vision Surgical) in highly myopic eyes.

SETTING

Department of Ophthalmology, Medical School, University of Crete, Vardinoyannion Eye Institute of Crete, Crete, Greece.

METHODS

Thirty-four myopic eyes of 19 patients were treated for high myopia with implantation of a silicone PRL in the posterior chamber. Mean patient age was 29.0 years +/- 7.9 (SD) (range 18 to 44 years). Manifest refraction in spherical equivalent (MR), uncorrected (UCVA) and best corrected (BCVA) visual acuity (decimal scale), intraocular pressure, higher-order aberrations (root-mean-square [RMS] wavefront error measured with a Shack-Hartmann wavefront sensor WASCA analyzer [Carl Zeiss, Meditec]), possible complications, and subjective symptoms were evaluated.

RESULTS

Phakic refractive lenses were successfully implanted in all eyes. Mean follow-up was 17.17 +/- 3.76 months (range 12 to 24 months). There was a statistically significant reduction in the MR (from -14.70 D +/- 2.65 D [range -20.75 D to -10.50 D] to -0.61 D +/- 0.89 D [range -2.25 D to 1.00 D]) (P<.001). Twenty-seven (79%) and 15 eyes (44%) were within +/-1.00 D and +/-0.50 D of target refraction, respectively. Mean UCVA significantly improved (from counting fingers to 0.62 +/- 0.28 (range 0.08 to 1.20) (P<.001). Mean BCVA also improved from 0.70 +/- 0.24 (range 0.10 to 1.00) to 0.85 +/- 0.24 (range 0.10 to 1.20) (P<0.001). Overall, there was a mean increase in BCVA of 1.5 +/- 1.5 lines (range loss of 2 lines to gain of 5 lines). There was no statistically significant difference in higher-order aberrations after PRL implantation (pre-PRL RMS: 0.18 microm +/- 0.08 microm [range 0.09 microm to 0.38 microm]; post-PRL RMS: 0.21 microm +/- 0.08 microm; [range 0.05 microm to 0.38 microm]) (P =.12).

CONCLUSION

The PRL showed encouraging results in treating high myopia. Additional patients and longer follow-up period are needed to detect the long-term efficacy and safety of this refractive lens.