Intraocular lens explantation and exchange. A review of lens styles, clinical indications, clinical results, and visual outcome

Indications and Outcomes of Intraocular Lens Explantation in a Tertiary Eyecare Center in Hungary between 2006 and 2020

Purpose

Our study aimed to evaluate the indications and outcomes of intraocular lens (IOL) explantation surgeries in a tertiary eyecare center in Hungary.

Materials and Methods

This retrospective study included all IOL explantation surgeries performed between 2006 and 2020 at the Department of Ophthalmology of Semmelweis University, Budapest, Hungary. There were no exclusion criteria for this study. For each patient, the demographics, clinical history, preoperative status, indications for IOL explantation, and operative and postoperative details were reviewed. Primary outcomes included explantation indications and the type of secondary implanted IOL.

Results

A total of 161 eyes from 153 patients were included (96 males; 62.7%); age at the time of the IOL explantation was 65.0 ± 17.4 years. The mean time between primary cataract surgery and IOL explantation was 8.5 ± 7.7 years. In total, 139 (86.3%) PCIOLs and 22 (13.7%) ACIOLs were explanted. The main indications for IOL explantation were dislocation (n = 133; 95.7%) and refractive cause (n = 2; 1.4%) in the PCIOL group. Among ACIOL explantations, the main reasons were pseudophakic bullous keratopathy (n = 14; 63.6%), dislocation (n = 4; 18.2%), and refractive cause (n = 2; 9.1%). In the PCIOL group, 115 (82.7%) primary IOLs were implanted in the capsular bag, 16 (11.5%) were sulcus fixated, and 8 (5.8%) were scleral fixated. The most frequent ocular comorbidities were previous vitrectomy (n = 50, 31.1%), previous ocular trauma (n = 45, 28.0%), glaucoma (n = 16, 9.9%), pseudoexfoliation syndrome (n = 15, 9.3%), and high axial myopia (n = 14, 8.7%). The most commonly used secondary IOL implant was the prepupillary iris-claw IOL (n = 115, 73.7%), followed by the retropupillary iris-claw IOL (n = 32, 20.5%). Uncorrected visual acuity (UCVA) was significantly better following IOL exchange in the entire sample (1.57 ± 0.61 (range: 2.40-0.05) vs. 0.77 ± 0.56 (range: 2.40-0.00); p < 0.001). Best-corrected visual acuity (BCVA) was maintained or improved in 80.7% of cases after IOL explantation.

Conclusions

The most common indication for IOL explantation at a tertiary eyecare center in Hungary is IOL dislocation, followed by pseudophakic bullous keratopathy. Prepupillary and retropupillary iris-claw IOL are the most frequently used secondary implants and their use resulted in a significant UCVA improvement following IOL exchange.

Reversible Multifocality Achieved Through Polypseudophakia

Simultaneous implantation of a monofocal or monofocal toric intraocular lens (IOL) into the capsular bag and a multifocal IOL into the ciliary sulcus, referred to as duet procedure, allows us to create multifocality that is more easily reversible than the implantation of a capsular bag-fixated multifocal IOL. The optical quality and results after the duet procedure are equivalent to those of a capsular bag-fixated multifocal IOL. Patients who cannot tolerate the side effects of multifocal optics or who develop an ocular condition leading to loss of function such as age-related macular degeneration (AMD) or glaucoma in the course of their lives may benefit from the reversibility of the procedure.

Intraocular Lens Exchange: Indications, Comparative Outcomes by Technique, and Complications

Purpose

To describe the indications, outcomes, and complications associated with intraocular lens (IOL) exchange.

Patients and Methods

To determine the relative frequency of postoperative complications between techniques for all patients undergoing IOL exchange from May 1, 2014 through August 31, 2020.

Results

IOL exchange was performed in 511 eyes of 489 patients (59.7% men; mean age: 67.0 ± 13.9 years, median time from cataract procedure to IOL exchange: 47.5 months). Mean uncorrected visual acuity significantly improved from 20/192 Snellen equivalent (logMAR 0.981) preoperatively to 20/61 (logMAR 0.487) at last follow-up (P < 0.001). Overall, 384 eyes (78.7%) met their desired refractive outcome within ±1.0 diopter (D). The most frequent complication was cystoid macular edema (CME) (n=39, 7.6%). Iris-sutured technique was associated with significantly greater frequency of subsequent IOL dislocation (10.3%) than 4-point scleral sutured (0%, P = 0.002), anterior chamber IOL (ACIOL, 1.5%, P = 0.01), and 2-point scleral sutured (0%, P = 0.03) techniques. Yamane scleral-fixation technique was associated with significantly greater frequency of developing IOL tilt (11.8%) than ACIOL (0%, P = 0.002), 4-point scleral sutured (1.1%, P = 0.01), 2-point scleral sutured (0%, P = 0.04), and iris-sutured (0%, P = 0.04) techniques.

Conclusion

IOL exchange significantly improved uncorrected visual acuity and more than three-quarters of eyes met the refractive goal. Certain techniques were associated with complications, including subsequent dislocation associated with iris-sutured technique and IOL tilt associated with Yamane scleral-fixation technique. This information may help guide surgeons in deciding between procedural techniques for individual patients during IOL exchange preoperative planning.

Fifteen years of IOL exchange: indications, outcomes, and complications

PURPOSE

To report the indications, frequency, and outcomes regarding intraocular lens (IOL) exchange in 2 university hospital tertiary referral settings over a period of 15 years.

SETTING

Ophthalmology departments of the University Hospital Antwerp and the University Hospital Leuven, Belgium.

DESIGN

Retrospective cross-sectional study.

METHODS

In this retrospective study, included were patients who underwent an IOL exchange between 2002 and 2017. Patient demographics, surgical indication, comorbidities, visual outcomes, and complications were reported. Patients who underwent IOL repositioning or add-on IOL implantation or extraction, and patients who were left aphakic, were excluded.

RESULTS

Included in the study were 492 eyes. The mean age was 66.0 ± 13.3 years (range 19-91 years). The mean time between primary surgery and IOL exchange was 54.61 ± 67.07 months (range 0-343 months). Primary indication for explantation was IOL opacification, and the most common ophthalmic comorbidity was a previous history of vitreoretinal surgery. Preoperatively, the mean uncorrected visual acuity (UCVA) and corrected distance visual acuity (CDVA) were 0.47 ± 0.27 (range 0-1) and 0.61 ± 0.32 (range 0-1.2), respectively. Postoperative UCVA and CDVA was 0.7 ± 0.3 (range 0-1.2) and 0.8 ± 0.28 (range 0.05-1.6), respectively. The increase in both CDVA and UCVA was statistically significant (P < .001, paired t test). The most common complication perioperatively was vitreous prolapse, which occurred in 61 eyes (16%).

CONCLUSIONS

IOL exchange is a challenging yet valuable treatment option for a wide spectrum of problematic IOL outcomes. The most common indication remains IOL opacification, although IOL dislocation and patient dissatisfaction are increasing as indications.

Reversibility of the duet procedure: Bilateral exchange of a supplementary trifocal sulcus-fixated intraocular lens for correction of a postoperative refractive error

Purpose

We present the case of a 49-year old female who underwent bilateral exchange of a supplementary trifocal sulcus-fixated intraocular lens (IOL) to correct a residual refractive error. Six months beforehand, she had been treated for hyperopia, astigmatism and presbyopia with a duet procedure to create reversible trifocality.

Observations

Refractive lens exchange with combined implantation of a monofocal toric IOL into the capsular bag and a trifocal supplementary IOL into the ciliary sulcus (duet procedure) had been performed in both eyes. Decreased uncorrected distance visual acuity due to the refractive outcome of −0.75 diopter sphere (DS)/-0.25 diopter cylinder (DC)x10° for the right eye and −1.0DS for the left eye as well as the perception of photic phenomena were inacceptable for the patient. In the second operations, we exchanged the supplementary IOLs to correct the residual refractive error and achieve the target refraction of emmetropia. UDVA increased from 0.50 logMAR in both eyes prior to the IOL exchange to −0.22 logMAR in the right eye and −0.20 logMAR in the left eye. Binocular uncorrected near and intermediate visual acuity were −0.10 logMAR and 0.00 logMAR respectively after exchanging the sulcus-fixated supplementary IOLs, allowing for complete spectacle independence.

Conclusions

This case demonstrates one of the most important benefits of the duet procedure: the possibility, if necessary, to easily remove or exchange the supplementary IOL from the ciliary sulcus. The duet procedure offers a safe treatment option in the event of postoperative complications like residual refractive error or intolerance to a multifocal optic.

Intraocular lens explantation in Spain: indications and outcomes at a tertiary referral center from 2010 to 2018

PURPOSE

To evaluate the causes of IOL explantation, techniques for secondary IOL implantation, visual outcomes and complications.

METHODS

Setting: Department of Ophthalmology Complexo Hospitalario Universitario A Coruña, Spain.

DESIGN

Retrospective study. All explanted IOLs from January 2010 to June 2018 were included. Medical records were reviewed to determine the surgical indication for IOL explantation, type of IOL implanted, time between surgeries, visual outcomes and surgical complications.

RESULTS

One hundred forty-one IOLs were explanted (134 patients). Mean time from original surgery to IOL explantation was 7.89 ± 5.81 years. Causes of IOL explantation were IOL dislocation (81.56%)-in-the-bag IOL dislocation (71.63%), out-of-the-bag IOL dislocation (9.9%)-corneal decompensation (12.05%), refractive surprise (3.5%), uveitis-glaucoma-hyphema syndrome (1.4%), IOL opacification (1.4%). Procedures for secondary IOL implantation were retropupillar iris-claw IOL (63.8%), flanged scleral fixated IOL (9.2%), three-piece IOL in ciliary sulcus (8.5%), angle-supported anterior chamber IOL (7.1%), in-the-bag IOL (3.5%), scleral fixated IOL with sutures (0.7%). Ten cases (7.1%) were left aphakic. Mean preoperative and postoperative logMAR CDVA were 1.34 ± 0.87 and 0.63 ± 0.69, respectively (p = 0.000). Mean preoperative IOP and postoperative IOP were 16.78 ± 4.49 and 15.53 ± 3.476 mmHg, respectively (p = 0.005). Complications include cystoid macular edema (7.8%), glaucoma (7.1%), IOL luxation (2.1%), retinal detachment (1.4%), trophic ulcer and leucoma (1.4%), corneal decompensation (1.4%).

CONCLUSIONS

In-the-bag IOL dislocation was the most frequent indication for IOL explantation, followed by pseudophakic bullous keratopathy. Simultaneous IOL exchange for a retropupillar iris-claw IOL was the most frequent procedure for secondary IOL implantation. Mean CDVA improved significantly and IOP decreased significantly after IOL explantation. The most frequent postoperative complication was cystoid macular edema.

Indications and Outcomes for the Removal of Intraocular Lens Implants in a Retinal Surgery Practice

BACKGROUND AND OBJECTIVE

To describe the reasons for and clinical outcomes of intraocular lens (IOL) removal, with or without exchange, in the setting of retina surgery.

PATIENTS AND METHODS

This is a retrospective, noncomparative, consecutive, interventional case series of patients undergoing IOL removal at an academic referral center performed by a single surgeon between 2002 and 2013. Data collected included baseline patient characteristics, visual acuity (VA), type of IOL, reason for IOL removal, and postoperative complications.

RESULTS

The study cohort included 63 eyes with IOL removal. Of these, 51 (81%) were left aphakic. For cases of IOL opacification or dislocated IOL (56), the decision to remove was made for 35 (63%) during concurrent retinal surgery due to obstruction in visualization. Overall, the most common reason for removal of the IOL was IOL opacities in 42 eyes (67%), followed by nonspecific nature of opacities (n = 19; 45%), oil artifact (n = 17; 40%), opaque nonvascular membranes (n = 4; 10%), and fibrovascular proliferation (n = 2; 5%). Other causes for removal were IOL dislocation (n = 14; 22%), endophthalmitis (n = 7; 11%), and broken IOL haptic (n = 1; 2%). The composition of the 42 IOLs with opacification included 19 (45%) silicone, 14 (33%) unspecified, five (12%) polymethyl methacrylate, and four acrylic (10%). From the 17 IOLs removed due to oil opacification, 15 (83%) were silicone, and two (17%) were unspecified. Postoperative complications included recurrent retinal detachment (n = 13; 21%), hypotony (n = 8; 13%), phthisis bulbi (n = 8; 13%), corneal edema (n = 7; 11%), cystoid macular edema (n = 5; 8%), elevated intraocular pressure (n = 3; 5%), vitreous hemorrhage (n = 3; 5%), hyphema (1; 2%), anterior synechiae (1; 2%), and subretinal hemorrhage (1; 2%) The mean (SD) immediate, 3 months, and final best-corrected VA in logMAR were 2.18 (0.47), 1.85 (0.82), and 1.97 (0.85).

CONCLUSION

The vitreoretinal surgeon must be prepared for IOL removal, especially if IOL opacification and dislocation compromise the view or capability to achieve primary retinal reattachment objectives. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:504-508.].

A Survey of Intraocular Lens Explantation: A Retrospective Analysis of 23 IOLs Explanted during 2005

Purpose

To evaluate the indications, lens styles, perioperative findings, and results of intraocular lens (IOL) explantation or exchange performed in the authors department in 2005.

Methods

The retrospective analysis comprised 22 patients (23 eyes). Twenty-one eyes had previous phacoemulsification and IOL implantation, one eye secondary aphakic IOL, and one eye phakic IOL implantation. The indications for IOL explantation/exchange and perioperative complications were evaluated. The best-corrected visual acuity (BCVA) before and after surgery was compared.

Results

Time from initial surgery to explantation/exchange varied from 1 to 121 months, median value was 46 months. The IOLs were explanted using local anesthesia and in 21 eyes replaced with new lens. Indications for IOL removal were opacification of the IOL in 12 eyes, malposition of the IOL in 5 eyes, postoperative refractive error in 2 eyes, recurrent toxic anterior segment syndrome in 1 eye, pseudophakic dysphotopsia in 1 eye, endothelial cell loss in phakic anterior chamber IOL in 1 eye, and visual discomfort with intraocular telescopic lens in 1 eye. The mean BCVA (decimal scale) before and after IOL explantation/exchange was 0.562±0.279 and 0.627±0.276, respectively. There was no significant difference in visual acuity before and after IOL exchange (Wilcoxon test).

Conclusions

The most frequent indications for IOL explantation/exchange were opacification of the IOL and IOL malposition. Surgeries were uneventful in most cases. Final visual results have been largely good. Long-term follow-up of patients with various types of IOLs should be maintained.

Decision-making and management of uveitic cataract

The visual outcome of uveitic cataract surgery depends on the underlying uveitic diagnosis, the presence of vision-limiting pathology and perioperative optimization of disease control. A comprehensive preoperative ophthalmic assessment for the presence of concomitant ocular pathology, with particular emphasis on macula and optic nerve involvement, is essential to determine which patients will benefit from improved vision after cataract surgery. Meticulous examination in conjunction with adjunct investigations can help in preoperative surgical planning and in determining the need for combined or staged procedures. The eye should be quiescent for a minimum of 3 months before cataract surgery. Perioperative corticosteroid prophylaxis is important to reduce the risk of cystoid macular edema and recurrence of the uveitis. Antimicrobial prophylaxis may also reduce the risk of reactivation in eyes with infectious uveitis. Uveitic cataracts may be surgically demanding due to the presence of synechiae, membranes, and pupil abnormalities that limit access to the cataract. This can be overcome by manual stretching, multiple sphincterotomies or mechanical dilation with pupil dilation devices. In patients <2 years of age and in eyes where the inflammation is poorly controlled, intraocular lens implantation should be deferred. Intensive local and/or oral steroid prophylaxis should be given postoperatively if indicated. Patients must be monitored closely for disease recurrence, excessive inflammation, raised intraocular pressure, hypotony, and other complications. Complications must be treated aggressively to improve visual rehabilitation. With proper patient selection, improved surgical techniques and optimization of peri- and post-operative care, patients with uveitic cataracts can achieve good visual outcomes.

A simple technique of intraocular lenses explantation for single-piece foldable lenses

Foldable intraocular lenses (IOLs) are most commonly used in modern-day cataract surgery. Explantation of these IOLs is not frequently encountered, but sometimes extreme situations may demand the same. Commonly explantation is achieved by bisecting the IOL inside the anterior chamber with a cutter and delivering the pieces out one by one. This may require corneal wound extension with associated damage and endothelial loss leading to visual deterioration. We devised a simple, innovative IOL explantation technique utilizing a modified Alcon A cartridge and snare. This can successfully refold the IOL to be explanted inside the eye and deliver it out through the same wound. The device has limitations with very thick optic lenses, multipiece, and silicon IOLs. In conclusion, we describe a simple, innovative, and reproducible technique to explant almost any single piece IOL without compromising the original surgery and yielding very satisfactory outcomes.

Morphologic Differences Observed by Scanning Electron Microscopy According to the Reason for Pseudophakic IOL Explantation

Purpose

To compare variations in surface morphology, as studied by scanning electron microscopy (SEM), of explanted intraocular lenses (IOLs) concerning the cause leading to the explantation surgery.

Methods

In this prospective multicenter study, explanted IOLs were analyzed by SEM and energy-dispersive X-ray spectroscopy. The IOLs were explanted in the centers of the research group from 2006 to 2012. The primary procedure was phacoemulsification in all cases.

Results

The study evaluated 40 IOLs. The main causes for explantation were IOL dislocation, refractive error, and IOL opacification. Those explanted due to dislocation demonstrated calcifications in 8 lenses (50%), salt precipitates in 6 cases (37.5%), and erythrocytes and fibrosis/fibroblasts in 2 cases (12.5%). In the refractive error cases, the SEM showed proteins in 5 cases (45.5%) and salt precipitates in 4 lenses (36.4%). In IOL opacification, the findings were calcifications in 2 of the 3 lenses (66.6%) and proteins in 2 lenses (66.6%).

Conclusions

A marked variation in surface changes was observed by SEM. Findings did not correlate with cause for explantation. Scanning electron microscopy is a useful tool that provides exclusive information regarding the IOL biotolerance and its interactions with surrounding tissues.

Phakic intraocular lens explantation: causes in 240 cases

PURPOSE

To describe the main causes of explantation of phakic intraocular lenses (PIOLs) according to the anatomical site of implantation (angle supported, iris fixated, or posterior chamber).

METHODS

This multicentric, retrospective, and consecutive study sponsored by the Spanish Ministry of Health comprised a total of 240 eyes (226 patients) explanted due to PIOL complications. Clinical data of 144 angle-supported lenses, 24 iris-fixated lenses, and 72 posterior chamber lenses explanted were recorded preoperatively and postoperatively.

RESULTS

Mean age of the patients at explantation was 46.30 ± 11.84 years (range: 25 to 80 years). The mean time between implantation and explantation was 381.14 ± 293.55 weeks (range: 0.00 to 1,551.17 weeks). It was 422.33 ± 287.81 weeks for the angle-supported group, 488.03 ± 351.95 weeks for the iris-fixated group, and 234.11 ± 4,221.60 weeks for the posterior chamber group. It was 8.10 ± 5.52 years for the angle-supported group, 9.36 ± 6.75 years for the iris-fixated group, and 4.49 ± 4.25 years for the posterior chamber group. This period of time was significantly shorter in the posterior chamber group (P < .001). Overall, the main causes of explantation were cataract formation (132 eyes, 55%), endothelial cell loss (26 eyes, 10.83%), corneal decompensation (22 eyes, 9.17%), PIOL dislocation/decentration (16 eyes, 6.67%), inadequate PIOL size or power (12 eyes, 5%), and pupil ovalization (10 cases, 4.17%). Cataract development was the cause of explantation in 51.39% of angle-supported cases, 45.83% of iris-fixated cases, and 65.28% of posterior chamber cases. Endothelial cell loss was the cause of explantation in 15.97% of angle-supported PIOLs, 8.33% of iris-fixated PIOLs, and 1.39% of posterior chamber PIOLs.

CONCLUSIONS

Cataract is the main cause of PIOL explantation, especially in posterior chamber PIOLs. In the angle-supported group, endothelial cell loss was the second cause of explantation.

Multifocal intraocular lens explantation: a case series of 50 eyes

OBJECTIVE

To assess the visual complaints, reasons, and patient satisfaction for multifocal intraocular lens (IOL) explantation.

DESIGN

Retrospective observational case series.

METHODS

This study evaluated 50 eyes of 37 patients who underwent multifocal IOL explantation followed by IOL implantation. Before and 3 months after IOL exchange surgery, we investigated the symptoms, reasons, patient demographics, clinical results, and patient satisfaction in eyes undergoing multifocal IOL explantation. Data collected included preoperative subjective and objective findings, reasons, IOL type, postoperative course, and patient satisfaction.

RESULTS

The most common complaints for IOL explantation were waxy vision, followed by glare and halos, blurred vision at far, dysphotopsia, blurred vision at near, and blurred vision at intermediate. The most common reasons for IOL explantation were decreased contrast sensitivity, followed by photic phenomenon, unknown origin including neuroadaptation failure, incorrect IOL power, preoperative excessive expectation, IOL dislocation/decentration, and anisometropia. The axial length was 25.13±1.83 mm. Of the explanted multifocal IOLs, 84% were diffractive and 16% were refractive. Monofocal IOLs accounted for 90% of the exchanged IOLs. Patient satisfaction was significantly improved from 1.22±0.55 preoperatively to 3.78±0.97 postoperatively, which was graded on a scale of 1 (very dissatisfied) to 5 (very satisfied) (Wilcoxon signed-rank test, P<.001).

CONCLUSIONS

Multifocal IOL explantation was required in some patients undergoing multifocal IOL implantation. IOL exchange surgery appears to be a feasible surgical option for dissatisfied patients with persistent visual symptoms after multifocal IOL implantation.

Glued trans-scleral intraocular lens exchange for anterior chamber lenses in complicated eyes: analysis of indications and results

PURPOSE

To determine the clinical outcomes after glued trans-scleral posterior chamber intraocular lens (IOL) exchange for anterior chamber (AC) IOL.

DESIGN

Retrospective case series.

METHODS

Eyes with AC IOL explantation with glued IOL implantation in a single setting at the Dr Agarwal Eye Hospital and Eye Research Centre, Chennai, India, from 2008 through 2012 were included. Data were collected from the patient records.

MAIN OUTCOME MEASURES

Corrected distance visual acuity (CDVA) in logarithm of the minimal angle of resolution units, intraocular pressure, AC reaction, AC depth, central corneal thickness, central macular thickness, endothelial cell density, and endothelial cell loss (percentage) were determined before and after IOL exchange.

RESULTS

Thirty-eight eyes with mean follow-up of 24.1 ± 15.4 months (range, 8 to 60 months) were analyzed. The indications were corneal decompensation (39.4%), malpositioned AC IOL (28.9%), uveitis (15.7%), glaucoma (13.1%), and broken haptic (2.6%). There was significant improvement in the postoperative CDVA (P = .000) and central corneal thickness (P = .000) after AC IOL removal. CDVA better than 20/60 was obtained in 65.7% eyes. Thirty-four (86.8%) eyes showed an increase in the CDVA after IOL exchange. The mean endothelial cell loss was 3.4 ± 2.4% (range, 0.13% to 10.5%). There was significant correlation between the CDVA and the central corneal thickness (P = .000). There was significant change in the AC depth (P = .000), the intraocular pressure (P = .005), and the AC inflammation (P = .000) after IOL exchange. The preoperative macular edema in 3 eyes resolved after surgery (mean central macular thickness, 205.6 ± 7.2 μm).

CONCLUSIONS

Glued trans-scleral fixated posterior chamber IOL exchange for AC IOL can be an excellent alternative in eyes with ocular complications related to AC IOL.

Severe endothelial cell loss with anterior chamber phakic intraocular lenses

We report the case of a highly myopic patient who developed severe bilateral endothelial cell loss following implantation of 2 angle-supported anterior chamber pIOL models, the Acrysof Cachet and the GBR (currently off the market).

FINANCIAL DISCLOSURE

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

Refractory cystoid macular oedema due to intraocular lens haptic perforating the iris

Cystoid macular oedema is a well-known complication of cataract surgery associated with intraocular lens decentration or dislocation. A 55-year-old man, who had undergone a phacoemulsification and intraocular lens implantation surgery two months previously was referred because of reduced vision in the right eye. Ocular examination revealed that one of the haptics had perforated the iris at 6 o'clock. There was cystoid macular oedema of the right eye. A topical non-steroid anti-inflammatory drug, followed by intravitreal injections did not produce a significant regression. Finally, the haptic was repositioned surgically and the macular oedema dramatically resolved. Correct placement of the intraocular lens might avoid post-operative complications including cystoid macular oedema.

[Iritis with destabilization of the intraocular pressure due to dislocation of a posterior chamber intraocular lens]

This report concerns the case of a 67-year-old male patient who underwent uncomplicated phacoemulsification with implantation of a posterior chamber intraocular lens (IOL). After an interval of 2 months the patient developed iritis together with an uncontrollable increase in intraocular pressure. After a detailed examination a dislocated haptic of the IOL was identified as the cause of the symptoms. The dislocation had led to uveitis-glaucoma-hyphema syndrome although no hemorrhage was observed. In addition to this complication the haptic had arroded the zonular complex which made implantation of an anterior chamber lens necessary. Although improvements in operating techniques, lens materials and designs have been made uveitis-glaucoma-hyphema syndrome has to be kept in mind. Surgical intervention is the only therapeutic option.

Long-term corneal endothelial cell changes in pediatric intraocular lens reposition and exchange cases

PURPOSE

To evaluate long-term corneal endothelial cell changes of intraocular lens (IOL) reposition and exchange in children.

SETTING

State key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060, China

METHODS

In this retrospective study, all IOL reposition and exchange procedures performed in patients under 14 years old between January 1999 and April 2009 were included. Follow-up outcomes included corneal endothelial cell density, hexagonality, coefficient of variance, average cell size.

RESULTS

IOL reposition procedures in 12 eyes (12 cases) (reposition group, RPG), and IOL exchanges in eight eyes (eight cases) (exchange group, EXG) were performed because of IOL pupillary capture or IOL dislocation. Median of follow-up was 44.5 months in RPG and 66.2 months in EXG. The density of corneal endothelial cells in RPG (2,053 ± 493/mm(2)) and EXG (2,100 ± 758/mm(2)) was significantly decreased in comparison to the control eyes (3,116 ± 335/mm(2)). Hexagonality of corneal endothelial cells and coefficient of variance showed no difference among the control group, RPG and EXG (P > 0.05).

CONCLUSIONS

The density of corneal endothelial cells was conspicuously decreased after IOL reposition or exchange procedures in childhood cases. Longer follow-up must be conducted in these cases.

Wavefront analysis and modulation transfer function of three multifocal intraocular lenses

Purpose:

To evaluate wavefront performance and modulation transfer function (MTF) in the human eye after the implantation of diffractive or refractive multifocal intraocular lenses (IOLs).

Materials and Methods:

This was a prospective, interventional, comparative, nonrandomized clinical study. Uncorrected distance and near visual acuity, and wavefront analysis including MTF curves (iTrace aberrometer, Tracey Technologies, Houston, TX, USA) were measured in 60 patients after bilateral IOL implantation with 6 months of follow-up. Forty eyes received the diffractive ReSTOR (Alcon), 40 eyes received the refractive ReZoom (Advanced Medical Optics) and 40 eyes, the Tecnis ZM900 (Advanced Medical Optics). The comparison of MTF and aberration between the intraocular lenses was performed using analysis of variance (ANOVA), followed by the Dunn test when necessary.

Results:

The mean uncorrected distance visual acuity was similar in all three groups of multifocal IOLs. The ReSTOR group provided better uncorrected near visual acuity than the ReZoom group (P < 0.001), but similar to the Tecnis group. Spherical aberration was significantly higher in the ReZoom group (P = 0.007). Similar MTF curves were found for the aspheric multifocal IOL Tecnis and the spheric multifocal IOL ReSTOR, and both performed better than the multifocal IOL ReZoom in a 5 mm pupil (P < 0.001 at all spatial frequencies).

Conclusions:

Diffractive IOLs studied presented similar MTF curves for a 5 mm pupil diameter. Both diffractive IOLs showed similar spherical aberration, which was significantly better with the full-diffractive IOL Tecnis than with the refractive IOL ReZoom.

Wavefront analysis, contrast sensitivity, and depth of focus after cataract surgery with aspherical intraocular lens implantation

PURPOSE

To determine whether implantation of an aspherical intraocular lens (IOL) results in reduced ocular aberrations and improved contrast sensitivity after cataract surgery without critical reduction of depth of focus.

DESIGN

Double-blinded, randomized, prospective study.

METHODS

In an intraindividual study of 25 patients with bilateral cataract, an aspherical IOL (Akreos Advanced Optic [AO]; Bausch & Lomb, Inc., Rochester, New York, USA) was implanted in one eye and a spherical IOL (Akreos Fit; Bausch & Lomb, Inc) in the fellow eye. Higher-order aberrations with a 5- and 6-mm pupil were measured with a dynamic retinoscopy aberrometer at 1 and 3 months after surgery. Uncorrected and best-corrected visual acuity and contrast sensitivity under mesopic and photopic conditions also were measured. Distance-corrected near and intermediate visual acuity were studied as a measurement of depth of focus.

RESULTS

There was no statistically significant difference between eyes in uncorrected and best-corrected visual acuity at 1 and 3 months after surgery. There was a statistically significant between-group difference in contrast sensitivity under photopic conditions at 12 cycles per degree and under mesopic conditions at all spatial frequencies. The Akreos AO group obtained statistically significant lower values of higher-order aberrations and spherical aberration with 5- and 6-mm pupils compared with the Akreos Fit group (P < .05). There was no significant difference in distance-corrected near and intermediate visual acuity between both groups.

CONCLUSIONS

Aspherical aberration-free Akreos AO IOL induced significantly less higher-order aberrations and spherical aberration than the Akreos Fit. Contrast sensitivity was better under mesopic conditions with the Akreos AO with similar results of depth of focus.

A contralateral eye study comparing apodized diffractive and full diffractive lenses: wavefront analysis and distance and near uncorrected visual acuity

PURPOSE

To evaluate intraindividual visual acuity, wavefront errors and modulation transfer functions in patients implanted with two diffractive multifocal intraocular lenses.

METHODS

This prospective study examined 40 eyes of 20 cataract patients who underwent phacoemulsification and implantation of a spherical multifocal ReSTOR intraocular lens in one eye and an aspheric Tecnis ZM900 multifocal intraocular lens in the other eye. The main outcome measures, over a 3-month follow-up period, were the uncorrected photopic distance and near visual acuity and the defocus curve. The visual acuity was converted to logMAR for statistical analysis and is presented in decimal scale. The wavefront error and modulation transfer function were also evaluated in both groups.

RESULTS

At the 3-month postoperative visit, the mean photopic distance uncorrected visual acuity (UCVA) was 0.74 +/- 0.20 in the ReSTOR group and 0.76 +/- 0.22 in the Tecnis group (p=0.286). The mean near UCVA was 0.96 +/- 0.10 in the ReSTOR group and 0.93 +/- 0.14 in the Tecnis group (p=0.963). The binocular defocus curve showed measurements between the peaks better than 0.2 logMAR. The total aberration, higher-order aberration and coma aberration were not significantly different between the groups. The spherical aberration was significantly lower in the Tecnis group than in the ReSTOR group. (p=0.004). Both groups performed similarly for the modulation transfer function.

CONCLUSION

The ReSTOR SN60D3 and Tecnis ZM 900 intraocular lenses provided similar photopic visual acuity at distance and near. The diffractive intraocular lenses studied provided a low value of coma and spherical aberrations, with the Tecnis intraocular lens having a statistically lower spherical aberration compared to the ReSTOR intraocular lens. In the 5 mm pupil diameter analyses, both intraocular lens groups showed similar modulation transfer functions.

Visual performance and biocompatibility of 2 multifocal diffractive IOLs

PURPOSE

To evaluate the distance and near functional capacity, wavefront error and biocompatibility in patients with 2 diffractive multifocal intraocular lenses (MIOLs).

SETTING

Ophthalmology Department of Chieti-Pescara University (Italy).

METHODS

This prospective study comprised 28 eyes of 28 senile cataract patients having phacoemulsification and implantation of the Tecnis ZM900 MIOL (Group 1) and the AcrySof ReSTOR MIOL (Group 2). The main outcome measures, over a 6-month follow-up period, were spherical equivalent, distance visual acuity at high and low contrast, near visual acuity, and defocus curve. Wavefront error was evaluated in both groups. Capsule opacification was also assessed.

RESULTS

The high and low contrast uncorrected and best corrected visual acuity for distance did not show statistically significant differences between the 2 groups. The distance corrected near visual acuity was 1.86 +/- 1.66 in Group 1 and 1.93 +/- 1.12 in Group 2. The depth of focus was 4.5 diopters in both groups. The root mean square of total aberration and of spherical and coma aberrations were significantly lower in Group 1 than in Group 2. A higher percentage of patients with Tecnis MIOLs showed a more severe grade of anterior fibrosis. Posterior opacification was minimal and not significantly different between the 2 groups.

CONCLUSION

Diffractive MIOLs were effective in improving functional capacity for distance and near and provided a good quality of vision due to a significant reduction in spherical aberration, particularly in the Tecnis MIOLs. The higher capsular biocompatibility of the ReSTOR MIOL compared with the Tecnis MIOL could ensure long-term stability.

Longitudinal study of intraocular lens exchange

PURPOSE

To analyze the indications for intraocular lens (IOL) exchange, interval between the first IOL implantation and the exchange, type and mix of IOLs used, effect on vision, and frequency of complications.

SETTING

Cincinnati Eye Institute-Cincinnati-Ohio-USA.

METHODS

This retrospective study comprised 49 eyes of 49 adult patients who had IOL exchange between 1986 and 2002 performed by the same surgeon. The mean age was 70 years old, and 55% were women. The mean interval between surgeries was 53.8 months and the mean follow-up, 35.6 months. The patients were divided into 2 groups according to the type of IOL originally implanted: anterior chamber (AC) or posterior chamber (PC).

RESULTS

There were 15 eyes with an AC IOL and 34 eyes with a PC IOL. The difference in mean age and follow-up were not statistically significant between groups. The mean interval between the primary surgery and IOL explantation was 82.3 months in the AC IOL group and 37.9 months in the PC IOL group. The main reason for IOL exchange was inflammation (53.34%) and dislocation/decentration (85.30%), respectively. The preoperative best corrected visual acuity was similar in both groups, and visual acuity was maintained or improved in 80%. Vitreous prolapse was the main intraoperative complication.

CONCLUSIONS

The primary indication for IOL exchange was intraocular inflammation in patients with an AC IOL and IOL malposition in patients with a PC IOL. The results confirm the safety and positive visual outcome in this complex group of patients.

Surgical and visual outcomes following exchange of opacified Hydroview intraocular lenses

AIM

To report the clinical and surgical outcomes following exchange of opacified Hydroview intraocular lenses (IOLs), and to relate the final visual and anatomic results to clinical and surgical variables.

METHODS

This is a prospective study of seventy-three eyes that underwent exchange of opacified Hydroview IOLs in Waterford Regional Hospital, Ireland. Preoperative, intraoperative and postoperative details were recorded.

RESULTS

This study comprised 73 eyes of 71 consecutive patients undergoing IOL exchange, performed at mean (+/-SD) intervals of 36.64 (+/-9.9) months following the primary cataract surgery. The mean (+/-SE) follow-up following the exchange procedure was 13 (+/-1) months (range: 1-45 months). The secondary IOL was placed in the capsular bag, in the sulcus, and in the anterior chamber in 22 (30.1%), 24 (32.9%) and 27 (37%) cases, respectively. The IOL exchange procedure was uneventful in 36 eyes (49.3%), whereas intraoperative events such as posterior capsule rupture, vitreous loss and zonular dehiscence were seen in the remainder (50.7%). Following the IOL exchange procedure, a significant improvement in best corrected visual acuity (BCVA) was noted at one and at three months, and at the final visit (Wilcoxon signed ranks test: p<0.001, p = 0.006, and p<0.001, respectively). Following exclusion of eyes with visually consequential ocular comorbidity, a better final BCVA was noted among those eyes where the secondary IOL was placed in the capsular bag or in the sulcus when compared with placement of the secondary IOL in the anterior chamber (IOL in the bag or sulcus: 26 eyes (35.6%), median (IQR) final BCVA: 0.2 (0.10-0.40); IOL in the anterior chamber: 19 eyes (26.02%), median (IQR) final BCVA: 0.5 (0.20-0.60); Mann Whitney U Test: p = 0.004).

CONCLUSION

IOL exchange is a technically challenging, but visually rewarding procedure. However, placement of the secondary IOL in the anterior chamber is associated with a poorer visual outcome when compared with placement of the secondary IOL in the sulcus or in the capsular bag.

Effect of optic material and haptic design on anterior capsule opacification and capsulorrhexis contraction

PURPOSE

To examine the influence of optic material (silicone and hydrophobic acrylic) and haptic design (one-piece and three-piece open loop) of sharp optic edge intraocular lenses (IOL) on anterior capsule opacification (ACO) and capsulorrhexis contraction.

DESIGN

Randomized, controlled, double-blind clinical trial with intraindividual comparison.

METHODS

This study was performed at the Department of Ophthalmology, Medical University of Vienna, Austria, and comprised 210 eyes of 105 patients with bilateral age-related cataract. In group 1 (n = 53 patients), a three-piece acrylic IOL was compared with a three-piece silicone IOL. In group 2 (n = 52 patients), the three-piece acrylic IOL was compared with the one-piece acrylic IOL. One year after the operation, standardized digital slit-lamp images of ACO were taken; 1 week and 1 year after the operation, digital retroillumination images were taken to assess capsulorrhexis size. The intensity of ACO was graded objectively (score, 0% to 100%), and the capsulorrhexis area (square millimeters) was determined objectively.

RESULTS

One year after surgery, the mean ACO score was 21% for the acrylic and 20% for the silicone IOL (P = .4) in group 1 and 18% for both the three-piece and one-piece acrylic IOLs (P = .87) in group 2. Concerning the amount of capsulorrhexis contraction, there was no significant difference between the IOL types that were evaluated in this study (after Bonferroni-Holm correction, P > .05).

CONCLUSION

In the hydrophobic sharp optic edge IOLs that were examined, neither the optic material nor the haptic design had an influence on the amount of ACO or capsulorrhexis contraction.

Changing indications for and improving outcomes of intraocular lens exchange

PURPOSE

To evaluate the indications for and outcomes of intraocular lens (IOL) exchange at the same clinical setting over the past decade, as well as compare the efficacy and safety of anterior chamber lens (AC-IOL) and posterior chamber lens (PC-IOL) implantation for IOL exchange.

DESIGN

Retrospective, nonrandomized case series.

METHODS

The charts of all patients who had an IOL exchange at the Eye Institute of Utah between January 1998 and December 2004 were reviewed. The rate, indications, and outcomes are compared with the data of our previous study conducted between 1986 and 1990.

RESULTS

This study comprised 51 eyes of 51 consecutive patients. The rate of IOL exchange was 0.77% of all cataract surgeries during the time considered. Incorrect IOL power (41.2%), decentration/dislocation (37.3%), and glare (7.8%) were the most common indications for IOL exchange. An AC-IOL was used in 14 eyes (27.5%) and a PC-IOL in 37 eyes (72.5%) for IOL exchange. None of the PC-IOLs was sutured to the sclera or iris. Overall, 90.2% of patients obtained a best-spectacle corrected visual acuity (BSCVA) of 20/40 or better. All eyes in AC-IOL group and 94.6% of eyes in PC-IOL group maintained within 1 line or improved 2 to 5 lines of the pre-exchange vision.

CONCLUSIONS

The improvements in IOL design and materials as well as surgical techniques have greatly minimized the incidence, changed the indications for, and improved the visual outcomes of IOL exchange over the past decade. Our study suggests that the open loop, flexible AC-IOL poses no greater risk than PC-IOL with respect to visual outcome and safety for IOL exchange. An AC-IOL may be preferable to a PC-IOL suture fixation for IOL exchange in the absence of posterior capsular support.

Transscleral fixation of a foldable intraocular lens in aphakic vitrectomized eyes

PURPOSE

To evaluate the clinical outcomes of transscleral fixation of a foldable intraocular lens (IOL) in eyes that had pars plana lensectomy combined with pars plana vitrectomy for severe vitreoretinal disease.

SETTING

Seoul National University Hospital, Seoul, Korea.

METHODS

The medical records of 21 patients who had a transscleral fixation of a foldable IOL after previous vitrectomy combined with lensectomy for severe posterior segment pathology were reviewed. The underlying vitreoretinal diseases were complicated proliferative diabetic retinopathy (n = 9), proliferative vitreoretinopathy (n = 5), traumatic retinal detachment (n = 3), intraocular foreign body (n = 2), and uveitic retinal detachment (n = 2). The postoperative best corrected visual acuity (BCVA) was compared with the preoperative BCVA. Autorefractometry and keratometry measurements and central endothelial cell counts were evaluated 1 day preoperatively and 6 months postoperatively.

RESULTS

The mean age of the patients was 54.5 years. The preoperative aphakic period ranged from 2 to 22 months. The visual acuity reached the preoperative BCVA by 2 months after surgery and was better than the preoperative BCVA at 6 months (P =.006) and at the final visit (P =.003). Six months postoperatively, the mean myopic shift by cycloplegic autorefractometry was -1.0 diopter (D) and the mean scalar shift in surgically induced keratometric cylinder, 1.0 D. The mean central corneal endothelial loss at 6 months was 6.7% (range 2.4% to 22.2%). The only vitreoretinal complications were a transient vitreous hemorrhage and a reopened macular hole that was reattached after fluid-gas exchange.

CONCLUSION

Transscleral fixation of a foldable IOL was safe and led to favorable visual outcomes in aphakic vitrectomized eyes with previous severe vitreoretinal disease.

Capsule measuring ring to predict capsular bag diameter and follow its course after foldable intraocular lens implantation

PURPOSE

To evaluate the extent of capsular bag shrinkage after cataract surgery with intraocular lens (IOL) implantation and develop a regression formula to predict postoperative capsular bag size.

SETTING

Eye Hospital, Johannes Gutenberg-University, Mainz, Germany.

METHODS

The axial length (AL), anterior chamber depth, and corneal radius in 58 eyes were measured preoperatively. Cataract surgery was by phacoemulsification followed by implantation of a 3-piece, acrylic, posterior chamber IOL. The capsular bag diameter and anterior capsulorhexis were measured intraoperatively and 1 day and 1, 3, and 6 months postoperatively using a Koch capsule measuring ring (HumanOptics).

RESULTS

The mean capsular bag size was 10.53 mm intraoperatively, 10.31 mm at 1 day, 9.62 mm at 1 month, 9.07 mm at 3 months, and 9.01 mm at 6 months. The mean capsular bag shrinkage over the entire postoperative period was 14.8% (P<.001). Of the parameters studied, only AL had a positive correlation with capsule shrinkage. The correlation was moderate but statistically significant (P =.001).

CONCLUSIONS

A correlation was found between capsular bag shrinkage and AL. Using preoperative biometric data, a regression formula of moderate validity was determined to predict capsular bag shrinkage.

Reasons for secondary surgical intervention after phacoemulsification with posterior chamber lens implantation

PURPOSE

To determine the indications for secondary surgical intervention in patients who had primary phacoemulsification with posterior chamber intraocular lens (IOL) implantation and to assess the final visual outcomes.

SETTING

Department of Ophthalmology, Scarborough Hospital, Scarborough, United Kingdom.

METHODS

The case notes of 17 patients (18 eyes) were reviewed to determine the reasons for secondary surgical intervention. From September 1997 to December 2000 (40 months), 4388 primary phacoemulsification procedures with posterior chamber IOL implantation were performed.

RESULTS

Fifteen eyes required secondary surgical interventions for lens-related factors and 3, for surgeon-related factors. All patients had satisfactory visual outcomes after the secondary intervention.

CONCLUSIONS

The indications for secondary intervention included unsatisfactory refractive outcome, posterior settlement of the IOL, unwanted imagery, inappropriate IOL power, and IOL dislocation. Secondary intervention can be performed safely and provides satisfactory final visual outcomes.

Posterior chamber intraocular lens supported by an intact vitreous face

We describe a technique of posterior chamber intraocular lens (IOL) implantation in eyes with inadequate capsule support caused by inadvertent or planned intracapsular cataract extraction (ICCE) or in eyes having secondary IOL implantation after previous ICCE. The procedure is only performed in eyes with an intact anterior vitreous face, no vitreous prolapse into the anterior chamber, and no vitreous loss. The anterior vitreous is pushed back by viscoelastic material or air. The viscoelastic material is injected under the iris to create a free space between the iris and anterior vitreous. A single-piece, C-loop, poly(methyl methacrylate) IOL is slid onto the iris to rest on the anterior vitreous face; care is taken not to disturb the anterior vitreous. The technique was used in 15 eyes with a follow-up from 19 months to 5 years. All eyes had a stable IOL at each follow-up, and the visual acuity was 6/12 or better at the last follow-up.

Complications and clinical outcomes of intraocular lens exchange in patients with calcified hydrogel lenses

PURPOSE

To evaluate the outcomes of intraocular lens (IOL) exchange in patients with calcified hydrogel IOLs.

SETTING

Ophthalmology departments of 2 university hospitals in Hong Kong, China.

METHODS

Fifteen patients developed loss of vision resulting from calcification of hydrogel IOLs. The calcified IOLs were explanted and replaced with new IOLs. The best corrected visual acuity before and after surgery was measured and compared.

RESULTS

The mean visual acuity was 0.03 (range 0.01 to 0.20) before IOL exchange and 0.20 (range 0.01 to 0.50) 3 months after; the difference was significant (P <.001). Acuity improved approximately 5 Snellen lines. Complications included posterior capsule rupture in 2 patients and zonular dehiscence in 3 patients; the secondary IOL was placed in the anterior chamber or ciliary sulcus in these patients. Three patients required cutting of the haptics before the calcified IOL could be removed.

CONCLUSION

Intraocular lens exchange was an effective treatment in patients with calcified hydrogel IOLs.

Visual discomfort after acrylic intraocular lens implantation

A 64-year-old man had phacoemulsification in both eyes. In January 1998, an Allergan SI-30NB silicone intraocular lens (IOL) with a 6.0 mm optic was implanted in the right eye. In April, an Alcon AcrySof MA60BN acrylic IOL with a 6.0 mm optic was implanted in the left eye. The following October, the patient experienced visual discomfort in the left eye. Two superior radial minikeratotomies were performed. The patient continued to have visual discomfort and the next month, a topographic ablation was performed in the same eye. In January 2000, the left IOL was replaced with a 5.5 mm Allergan SI-55NB silicone IOL. Visual impairment resolved 1 day after surgery.

[History of the development of intraocular lenses]

Even though cataract surgery has been practiced for over 2000 years, modern cataract surgery started just some 50 years ago. with the first IOL implantation by Sir Harold Ridley. The development of intraocular lenses was accompanied by great successes and disasters. With the fast development of cataract surgical techniques over the past 15 years (ECCE, Phacoemulsification, Capsulorhexis) a successful marriage between IOL-developments and surgery was established. Indication profiles for cataract surgery and IOL implantation extended to more and more patient groups. At this time classical cataract surgery is further developing into refractive intraocular lens surgery to correct higher ametropia in clear lens or phakic eyes. This development was only possible because of the improvements of surgical techniques and implants in classical cataract surgery.

A comparison of visual results and complications in eyes with posterior chamber intraocular lens dislocation treated with pars plana vitrectomy and lens repositioning or lens exchange

PURPOSE

To compare the visual results and the postoperative complications in eyes with posterior chamber intraocular lens (PCIOL) dislocation that underwent pars plana vitrectomy with lens repositioning with eyes that underwent pars plana vitrectomy with lens exchange.

DESIGN

Nonrandomized consecutive comparative case series.

PARTICIPANTS

Fifty-nine eyes (27 right eyes and 32 left eyes) of 56 subjects (28 women and 28 men) ranging in age from 59 to 90 years. Mean follow-up was 34 months.

METHODS

A comparison of the best-corrected preoperative visual acuities, final visual acuities, and postoperative complications in subjects with dislocated PCIOLs that underwent pars plana vitrectomy. Logarithm of the minimum angle of resolution (LogMAR)-converted visual acuities were used for comparison. Categorical data were analyzed by Fisher's exact test, and population means were compared by a pooled Student's t test.

MAIN OUTCOME MEASURES

Final mean visual acuities, change in mean visual acuities, and postoperative complications.

RESULTS

For all 59 eyes the mean preoperative visual acuity was 20/152, and the mean final visual acuity was 20/48. Final visual results were similar between the eyes that underwent lens repositioning (20/55) and the eyes that underwent lens exchange (20/43; P = 0.19). Final visual results were also similar between the eyes that underwent lens exchange with sutured PCIOL placement (20/51) and the eyes that underwent lens exchange with anterior chamber intraocular lens (ACIOL) placement (20/38; P = 0.26). Final mean visual acuity in eyes that received an ACIOL (20/38) was better than in eyes that underwent repositioning of the dislocated lens into the ciliary sulcus (20/65; P = 0.01). The mean increase in visual acuities was greater for eyes with ACIOL placement compared with eyes with sutured PCIOL placement (P = 0.01). For all eyes, final visual results were unaffected by a concurrent diagnosis of age-related macular degeneration (20/52; P: = 0.71), glaucoma (20/48; P = 0.95), or postoperative cystoid macular edema (20/55; P = 0.45). Final visual acuities were significantly worse in eyes with a detectable preoperative afferent pupillary defect (20/200; P<0.0001). Postoperative retinal detachments developed in 4 of 29 eyes (14%) that underwent lens repositioning and in 2 of 30 eyes (7%) that had lens exchange (P = 0.42). Postoperative lens subluxations occurred in 6 of 29 eyes (21%) that underwent lens repositioning and in 1 of 30 eyes (3%) that underwent lens exchange (P = 0.05).

CONCLUSIONS

The final visual results in eyes with dislocated PCIOLs that underwent pars plana vitrectomy with lens repositioning were similar to the visual results obtained in eyes that underwent pars plana vitrectomy with lens exchange. For eyes that underwent lens exchange, final visual results in eyes that received an ACIOL were similar to the visual results obtained in eyes that received a PCIOL; however, eyes with an ACIOL showed a greater increase in mean visual acuity. Eyes with a preoperative afferent pupillary defect had worse final visual results.

Explantation of intraocular lenses

Cataract surgery has evolved recently along with the development of intraocular lenses. With this evolution of intraocular lenses from anterior chamber and iris-fixated lenses to more modern foldable posterior intraocular lenses has come an evolution in the complications that necessitate removal of the intraocular lens. Early generations of anterior chamber and iris-fixated intraocular lenses often had severe complications associated with them, such as pseudophakic bullous keratopathy, uveitis-glaucoma-hyphema syndrome, and chronic cystoid macular edema. With modern foldable intraocular lenses, decentration-dislocation and incorrect lens power, and glare and optical aberrations are leading indications for explantation. Some complications appear to be unique to particular styles of modern intraocular lenses, with incidence of glare and optical aberrations increasing, especially in acrylic and multifocal intraocular lenses. The clinical outcomes after an intraocular lens explantation or exchange have also improved markedly with the advent of modern foldable intraocular lenses. Postoperative visual acuity results are dependent on the preoperative complications associated with the explanted intraocular lens. Final visual results after exchange of modern foldable intraocular lenses have been uniformly good. This is probably because of fewer severe complications that lead to explantation of the intraocular lens.

Intraocular lens removal from [corrected] patients with uveitis

PURPOSE

To report a series of patients with uveitis and cataract who had undergone cataract extraction with posterior chamber intraocular lens implantation and who subsequently had the intraocular lens removed because of progressive intraocular damage from inflammation.

METHODS

Review of the records of 19 patients after removal of a posterior chamber intraocular lens. The decision to perform surgery was based on standard criteria after evaluation at a single uveitis referral center.

RESULTS

The complications leading to intraocular lens removal were perilental membrane (eight eyes), chronic low-grade inflammation not responding to anti-inflammatory treatment (eight eyes), and cyclitic membrane resulting in hypotony and maculopathy (three eyes). After intraocular lens removal the inflammation subsided and the visual acuity improved or stabilized in 14 of the 19 eyes. The causes of further reduction in the visual acuity of the other five patients were macular edema (two patients), maculopathy resulting from hypotony (one patient), retinal detachment (one patient), and vitreous hemorrhage (one patient).

CONCLUSIONS

Intraocular lens implantation can form part of a reasonable plan for visual rehabilitation of patients with uveitic cataract, but inclusion of an intraocular lens in the plan is not always in the overall long-term best interest of the patient. Intraocular lens removal may salvage useful vision for patients who continue to exhibit complications secondary to uveitis after cataract extraction and intraocular lens implantation, provided the intraocular lens is removed before irreparable damage has been done to macula or optic nerve.

Radial keratotomy to treat myopic refractive error after cataract surgery

PURPOSE

To assess the predictability and effectiveness of radial keratotomy in patients with myopic refractive error and unacceptable anisometropia after cataract surgery.

SETTING

A prospective multicenter study.

METHODS

This study comprised 40 eyes of 40 Japanese patients who had had cataract surgery. Radial keratotomy was performed, and the 6 month postoperative data were analyzed.

RESULTS

Mean patient age was 71.0 years +/- 7.4 (SD) (range 51 to 84 years) and mean preoperative anisometropia -3.41 +/- 1.69 D (range -1.25 to -7.75 D). The surgery decreased mean anisometropia to -1.01 +/- 0.94 D (P < .000001, Wilcoxon signed-rank test), a mean reduction of 2.22 +/- 1.23 D (range 0.75 to 5.88 D). Postoperative anisometropia ranged from 0.81 to -3.13 D. The surgical effects were overestimated by the nomograms developed for the correction of naturally occurring myopia in the eyes of white patients. Multiple regression analysis revealed that optical zone size and number of incisions were significantly correlated with the amount of myopic correction, and the regression equation (R2 = 0.77) was expressed as follows: Effects = (-1.45 x optical zone size) + (0.24 x incision number) + 7.60. A new nomogram was derived based on this equation.

CONCLUSIONS

Radial keratotomy was a safe and efficient procedure to treat myopic refractive error in pseudophakic eyes. Separate nomograms are necessary for white and Asian populations.