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

Specifying Risk of Intraocular Lens Opacification After Endothelial Keratoplasty for Different Intraocular Lens Models: A Retrospective Monocentric Cohort Study

PURPOSE

The aims of this study were to calculate the specific risk of opacification for different intraocular lens (IOL) models and to determine whether differences exist, even between lenses made of similar acrylic materials.

METHODS

This is a retrospective cohort study of all patients who underwent endothelial keratoplasty (EK), either after or in conjunction with cataract surgery, from June 2009 to October 2020 at Fundación Jiménez Díaz Hospital.

RESULTS

Three hundred seventy-two eyes of 308 patients with a median follow-up of 856 days [interquartile range (IQR): 384-1570] were included, of which 128 IOLs were hydrophobic, 120 hydrophilic, and 124 unknown. 12.9% of IOLs opacified after a median of 466 days (IQR: 255-743). Visual acuity (VA) was significantly lower in the opacified IOL group [0.51 (IQR: 0.36-1.13)] compared with the nonopacified group [0.22 (IQR: 0.11-0.65)] ( P < 0.001). IOL explantation and exchange was performed in 10 eyes, in which VA improved markedly, from 1.75 (IQR: 0.99-3.00) to 0.60 (IQR: 0.36-0.86) ( P = 0.004). IOL material and opacification events were not independent ( P < 0.001). Significant differences were found between the Akreos ADAPT AO and MI60P models and the Asphina 409M model ( P = 0.022). No significant differences were found in the opacification ratio for hydrophilic IOLs in the clinical diagnosis ( P = 0.11), the type of EK ( P = 0.25), the rebubbling rate ( P = 0.44), or the tamponade used ( P = 0.36).

CONCLUSIONS

Hydrophilic lenses should be avoided in patients at risk of requiring EK. It is important to know the probability of opacification of each IOL model to balance risk and benefits when planning an EK procedure because not all lenses opacify equally. Opacification is an unwanted event with a negative impact on VA, making IOL explantation and exchange the only viable treatment, although one that is not without risks.

Late intraocular lens exchange in dissatisfied patients with multifocal intraocular lens implantation

Intraocular lens (IOL) exchange may be required after multifocal IOL implantation due to dissatisfaction. Late IOL exchange is more challenging when it is done with capsulotomy. We presented a retrospective case series study enrolling four consecutive eyes reviewing late IOL exchange due to decreased vision and dysphotopsia. High residual hyperopia, astigmatism, and IOL tilt occurred in 3 eyes, respectively. The mean time to the IOL exchange was 15.8 ± 10.63 months. After separation of the adhesions by visco-dissection assisted with a 27-gaze needle and sinskey hook, IOL was explanted. One-piece IOL was implanted in the bag in two eyes without posterior capsulotomy, whereas three-piece IOL was implanted in the sulcus after viscoelastic tamponade in the other 2 eyes with capsulotomy. No complication occurred and dysphotopsia disappeared. The mean logarithm of the minimum angle of resolution best-corrected visual acuity significantly improved from 0.33 ± 0.12 preoperatively to 0.11 ± 0.13 postoperatively. In conclusion, late IOL exchange could be safely performed with proper technique and achieve good results.

Visual outcomes after optic exchange of a modular intraocular lens

PURPOSE

To evaluate the effectiveness of the Harmoni Modular IOL (HMIOL).

SETTING

3 study sites.

DESIGN

Prospective, multicenter clinical study.

METHODS

HMIOL is a foldable, posterior chamber lens with separate base and exchangeable optic components. Eligible adults undergoing cataract surgery received HMIOL in the study eye (monovision target -1.50 diopters [D]) and standard monofocal IOL in contralateral eye (control). After 3 months, subjects could undergo optic exchange based on visual outcomes. End points included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest refractive spherical equivalent (MRSE). Follow-up was 12 months or greater postoperatively.

RESULTS

114 subjects had successful HMIOL implantation in study eye and control IOL in contralateral eye. At 3 months, subjects could undergo optic exchange if unsatisfied with monovision; 65 eyes had optic exchange (exchange cohort), and 49 eyes had no exchange (no exchange cohort). In exchange cohort, the proportion of eyes with UDVA of 20/40 or greater and of 20/20 or greater increased 3 months after optic exchange vs preexchange levels by 23% (97% vs 74%) and 40% (49% vs 9%), respectively. In all cohorts, 95% of subjects or greater achieved UDVA of 20/40 or greater after 12 months or greater. Control and no exchange cohorts achieved CDVA of 20/40 or greater by 3 months; 97% of eyes or greater had CDVA of 20/40 or greater at 12 months after optic exchange. In exchange cohort, the proportion of eyes with MRSE within ±0.50 D and ±1.00 D of target changed by 57% and 36%, respectively, from preexchange (20% and 59%, respectively) to 12 months postexchange (77% and 95%, respectively), reaching levels similar to control subjects (72% and 97%, respectively).

CONCLUSIONS

HMIOL provided visual outcomes comparable with standard monofocal IOLs.

Explantation/exchange of the components of a new fluid-filled, modular, accommodating IOL

PURPOSE

To evaluate the ease of replacement and capsular stability of a new fluid-filled, modular, accommodating intraocular lens (IOL) system composed of a monofocal base lens with a fluid lens clipped inside of it.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN

Experimental study.

METHODS

Five New Zealand rabbits underwent bilateral phacoemulsification with implantation of the test lens (Juvene, LensGen, Inc.) in both eyes (4 rabbits), or a control IOL in 1 eye (AcrySof, Alcon Laboratories, Inc.) and the test IOL in the other (1 rabbit). At 2 weeks, the 4 rabbits with bilateral Juvene IOLs had the clipped-in fluid lens exchanged for a new fluid lens in 1 eye, and the base and fluid lenses exchanged for a control lens in the contralateral eye. Slitlamp examinations were performed weekly for 4 weeks. The globes were enucleated and evaluated with ultrasound biomicroscopy, grossly from the posterior Miyake-Apple view, and histopathologically.

RESULTS

Explantation/exchange of the fluid lens was considered straightforward by the surgeon. Explantation of the base lens (4) was also safely performed, albeit more demanding, without any signs of damage to the capsular bag under clinical, ultrasound biomicroscopy, and pathological examination in the exchanged eyes. Less capsular bag opacification was observed with the Juvene lens system.

CONCLUSIONS

Explantation/exchange of the fluid lens component, or both fluid and base lenses, of this new lens system can be safely accomplished if necessary, because of its modular design and the relative lack of postoperative capsular bag opacification associated with it.

Intraocular lens extraction using the cartridge pull-through technique

ABSTRACT

Current intraocular lens (IOL) explantation techniques are limited to cutting the optic and removing the pieces through a small incision, or folding single piece acrylic IOLs using a two-handed technique. Poor execution of IOL explantation can result in injury to intraocular structures, including the corneal endothelium and iris. The minimally invasive "cartridge pull-through technique" was invented, using a cartridge for IOL implantation and novel forceps optimized for secure grasping of the IOL for removal. This method involved less manipulation in the anterior chamber, thereby reducing the risks of complications such as corneal and iris injuries. A "dropped IOL" lying on the retinal surface can be extracted directly without lifting it onto the iris first. The cartridge-pull through technique offers a more streamlined and potentially safer approach for IOL explantation.

Delayed surface opacification of a hydroview intraocular lens

The insertion of an intraocular lens during cataract surgery is routine but delayed opacification of hydrophilic foldable intraocular lenses (IOLs) has been increasingly noticed as a late post-operative complication. Such opacification may present with reduced visual acuity and can be diagnosed with slitlamp biomicroscopy. Lens explantation may be required. We report an 89-year-old female presenting with opacification of a Hydroview IOL and correlate the clinical findings of the lens in situ with the light microscopy of the explanted lens, as well as transmission electron microscopy (TEM), scanning electron microscopy (SEM) and elemental analysis. Pathological analysis of an explanted IOL may assist in a better understanding of the condition and may become relevant in medico-legal proceedings.

Evaluation of Safety Following Optic Exchange of a Modular Intraocular Lens

PURPOSE

To characterize safety of optic exchange using a modular lens.

SETTING

3 study sites (New Zealand, Philippines).

DESIGN

Prospective clinical study.

METHODS

Harmoni modular intraocular lens (HMIOL) with separate base and optic components was implanted in the study eye (monovision target -1.5 D). Contralateral eyes received standard monofocal lenses. Subjects could elect optic exchange 3 months after primary implantation. Adverse events (AEs) and endothelial cell loss (ECL) were assessed through 12-months follow-up.

RESULTS

114 subjects successfully received HMIOL and 114 received control lens in contralateral eye. At month 3, 65 HMIOL eyes had optic exchange due to unsatisfactory visual outcome from high monovision (Exchange cohort); 49 eyes received no exchange (No Exchange cohort). Exchange, No Exchange, and Control cohorts reported ocular AEs in 10 (15%), 6 (12%), and 14 (12%) eyes. No posterior capsular rupture occurred during optic exchange procedures. Short-term (12-month) posterior capsule opacification (PCO) evaluation showed all eyes had PCO grade ≤1 at month 12; no YAG capsulotomy was performed in the Exchange cohort. No Exchange and Exchange cohorts had similar ECL at 3 months versus preoperative baseline (-4.5%, n=48 and -4.0%, n=65). In the Exchange cohort, additional 2.7% ECL occurred 3 months after optic exchange compared with pre-exchange baseline; ECL was significantly below the 14% threshold (P<0.001) and was 5.8% at 12 months.

CONCLUSIONS

HMIOL safety outcomes were comparable with standard monofocal lenses; HMIOL may provide an effective method for correcting postoperative refractive errors.

Transection and explantation of intraocular lenses using femtosecond lasers

We present 2 cases in which a femtosecond laser was used in vitro to transect hydrophilic acrylic intraocular lenses (IOLs). At 8 μJ with 3 μm spot separation and 6 μm line separation, no charring occurred and there was no increase in total organic carbon. In vivo, the IOLs were successfully transected in the capsular bag (Case 1, opaque IOL) and the sulcus (Case 2, subluxated IOL post-pneumatic displacement of submacular hemorrhage) and explanted through a clear corneal incision (∼3.0 mm). At 3 months, in Case 1, the corrected distance visual acuity (CDVA) improved from 6/24 to 6/5, astigmatism improved by 0.23 diopters, and endothelial cell density (ECD) remained unchanged (1935 to 2210 cells/mm²); in Case 2, the CDVA was hand motion, astigmatism remained unchanged, and ECD decreased (1960 to 1600 cells/mm²), possibly as a result of complex surgery. Femtosecond IOL transection and explantation may be a clinically safe and feasible option for surgeons.

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.

Intraocular Lens Fragmentation Using Femtosecond Laser: An In Vitro Study

PURPOSE

To transect intraocular lenses (IOLs) using a femtosecond laser in cadaveric human eyes. To determine the optimal in vitro settings, to detect and characterize gasses or particles generated during this process.

METHODS

A femtosecond laser was used to transect hydrophobic and hydrophilic acrylic lenses. The settings required to enable easy separation of the lens fragment were determined. The gasses and particles generated were analysed using gas chromatography mass spectrometer (GC-MS) and total organic carbon analyzer (TOC), respectively.

RESULTS

In vitro the IOL fragments easily separated at the lowest commercially available energy setting of 1 μJ, 8-μm spot, and 2-μm line separation. No particles were detected in the 0.5- to 900-μm range. No significant gasses or other organic breakdown by products were detected at this setting. At much higher energy levels 12 μJ (4 × 6 μm spot and line separation) significant pyrolytic products were detected, which could be harmful to the eye. In cadaveric explanted IOL capsule complex the laser pulses could be applied through the capsule to the IOL and successfully fragment the IOL.

CONCLUSION

IOL transection is feasible with femtosecond lasers. Further in vivo animal studies are required to confirm safety.

TRANSLATIONAL RELEVANCE

In clinical practice there are a number of large intraocular lenses that can be difficult to explant. This in-vitro study examines the possibility of transecting the lasers quickly using femtosecond lasers. If in-vivo studies are successful, then this innovation could help ophthalmic surgeons in IOL explantation.

Outcomes of small aperture corneal inlay implantation in patients with pseudophakia

PURPOSE

To evaluate the improvement in near visual acuity after KAMRA corneal inlay (AcuFocus, Inc., Irvine, CA) implantation in patients with pseudophakia.

METHODS

A retrospective study analysis of patients with pseudophakia undergoing monocular corneal inlay implantation in the non-dominant eye was performed. The inlay was implanted monocularly in the non-dominant eye of patients. Manifest refractive spherical equivalent, uncorrected distance visual acuity, corrected distance visual acuity, uncorrected near visual acuity, and corrected near visual acuity were evaluated. The follow-up period was 3 months.

RESULTS

Thirteen eyes from 13 patients were evaluated. Four patients underwent LASIK for improved distance acuity at the time of inlay implantation. Mean uncorrected near visual acuity improved five lines (from J10 to J4) postoperatively. Mean uncorrected distance visual acuity, corrected distance visual acuity, and corrected near visual acuity remained stable and were 20/20, 20/16, and J1, respectively, before and after KAMRA implantation. Three eyes lost two lines and 1 eye lost one line of uncorrected distance visual acuity. Two eyes lost two lines and 1 eye lost 1 line of corrected distance visual acuity. Mean manifest refractive spherical equivalent changed before and after KAMRA implantation from -0.01 ± 1.07 diopters (D) (range: 2.25 to -1.88 D) to -1.12 ± 0.87 D (range: 0.25 to -2.75 D), respectively.

CONCLUSIONS

Implantation of a small aperture corneal inlay improved uncorrected near visual acuity while maintaining uncorrected and corrected distance visual acuity in monofocal patients with pseudophakia.

Piggybacking technique for vitreous protection during opacified intraocular lens exchange in eyes with an open posterior capsule

We describe a surgical technique for the safe exchange of opacified 1-piece IOLs in eyes that have had a neodymium:YAG laser posterior capsulotomy. Initially, the opacified IOL is freed from the capsule adhesions using a dispersive ophthalmic viscosurgical device, which is also injected beneath the opacified IOL to protect the vitreous interface. The IOL is then brought into the anterior chamber. A new 3-piece clear IOL is injected before the opacified IOL is removed and is placed behind the opacified IOL, preventing the vitreous from prolapsing. The pupil is constricted pharmacologically, and the opacified IOL is removed through a standard 2.75 mm corneal incision using the hinge technique.

FINANCIAL DISCLOSURE

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

Opacification of the intraocular lens implant following uneventful Descemet's stripping endothelial keratoplasty

A 74 year old pseudophakic patient developed opacification of a pre-existing intraocular lens implant following Descemet's stripping endothelial keratoplasty which may have been triggered by the presence of air in the anterior chamber.

Intraocular lens exchange through a 3.2-mm corneal incision for opacified intraocular lenses

Aim:

The aim was to evaluate visual and refractive results and complications of intraocular lens (IOL) exchange through a 3.2 mm corneal incision for opacified IOLs.

Materials and Methods:

This retrospective study comprised 33 eyes of 32 patients with IOL opacification requiring an IOL exchange between July 2003 and March 2007. Exchange surgery was performed through a 3.2-mm temporal clear corneal incision followed by implantation of a new foldable hydrophobic IOL. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), topographical astigmatism, and refractive cylinder were evaluated. Surgically induced astigmatism (SIA) was calculated and complications were recorded.

Results:

Opacification was observed in 25 eyes (76%) with Aqua-Sense, 3 eyes (9%) with Hydroview, 3 eyes (9%) with MemoryLens IOLs, and 2 eyes (6%) with DgR. The mean follow-up period was 36.54 months. An uneventful IOL exchange was achieved in 18 eyes (55%). Zonular dehiscence occurred in 9 eyes (27%), and posterior capsule tear developed in 4 eyes (12%). The mean preoperative BSCVA (mean ± standard deviation, decimal scale) was 0.13 ± 0.08 (mean: 20/150, range 20/2000 to 20/60) and improved to 0.63 ± 0.18 (mean: 20/32, range 20/60 to 20/20, P < 0.001). The mean SIA was 0.70 D. Seven eyes (21%) had 0.5 D or lower SIA.

Conclusion:

IOL exchange is a technically challenging procedure with potential risks of reversing the advantages of a prior small-incision cataract surgery. The use of a small corneal incision for IOL exchange could preserve the advantages of modern phacoemulsification surgery with acceptable SIA related to the procedure.

Clinical efficacy and complications of intraocular lens exchange for opacified intraocular lenses

PURPOSE

To evaluate the clinical efficacy and complications of intraocular lens (IOL) exchange.

METHODS

A review of medical records was performed for 52 eyes that had undergone an IOL exchange due to IOL opacification. Surgical complications and their incidences were analyzed. The mean best corrected visual acuity (BCVA) after the IOL exchange was compared with the mean pre-exchange BCVA and with the mean BCVA after the initial IOL implantation. Prediction error of refraction and biometric data obtained for the IOL exchange were, if available, compared with those obtained for the initial IOL implantation. The prediction error for the IOL exchange, calculated from the biometric data obtained before the IOL exchange, was compared with that calculated from the measurements obtained before the initial IOL implantation.

RESULTS

The overall complication rates were low and no serious complications were found. The mean BCVA improved significantly after the IOL exchange and was not significantly different from that obtained after the initial IOL implantation. However, the refractive prediction for the IOL exchange was not as good as it was for the initial IOL implantation, which was thought to be related with difficulties in axial length (AL) measurements. Biometric data taken before the initial IOL implantation was associated with a significantly better refractive prediction than those taken before the IOL exchange.

CONCLUSIONS

IOL exchange was both efficacious and safe for visual recovery. However, IOL exchange was related with increased difficulty of predicting postoperative refraction; difficulties in AL measurements are the suggested cause.

Mineralization of radiation-crosslinked polyvinyl alcohol/polyvinyl pyrrolidone hydrogels

A study of the calcification of the polyvinyl alcohol/polyvinyl pyrrolidone (PVA/PVP) hydrogels during their exposure to a calcium chloride solution or a simulated body fluid has been carried out. On the basis of the experiments, using a two-compartment permeation cell, the diffusion of calcium ions and their subsequent deposition in the hydrogels were elucidated. Steady-batch experiments were also performed to further elaborate the deposition pattern and the types of calcium deposits. It was demonstrated that Fick's second law of diffusion can describe the diffusion of calcium ions through PVA/PVP hydrogels at 310 K. The diffusion coefficient was determined to be (4.4+/-0.1)x10(-10) m2/s and the partition coefficient for the hydrogels was 0.06. Formation of calcium deposits was noticed taking place both on the surface and inside the hydrogels. The deposits formed on the surface have flake morphology, while the deposits inside the hydrogels are more like globular aggregates. Both types of deposits have been characterized as being comprised calcium and hydroxyl ion deficient apatites with chloride ions the most likely substituting species at the hydroxyl sites.

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.

Hydrophilic acrylic intraocular lens exchange: Five-year experience

PURPOSE

To evaluate clinical outcomes of opacified SC60B-0UV intraocular lens (IOL) (MDR, Inc.) and clear SC60B-0UV IOL exchange.

SETTING

Department of Ophthalmology, Queen's Hospital, Burton-on-Trent, United Kingdom.

METHODS

In a prospective audit, 149 patients with 152 SC60B-0UV hydrophilic acrylic IOLs were monitored over 5 years. Perioperative complications were evaluated. The best spectacle-corrected visual acuity, subjective quality of vision, and VF-14 scores were compared preoperatively and postoperatively.

RESULTS

Ninety-eight IOLs developed opacification; 52 IOLs were exchanged between February 1999 and October 2004. The lens exchange procedure was uneventful in 39 eyes (75%). Perioperative complications included zonular dehiscence and posterior capsule rupture in 12 eyes (23.1%), total capsule-IOL extraction in 4 eyes (7.7%), iridodialysis in 3 eyes (5.8%), hyphema in 2 eyes (3.8%), and retained haptics in 5 eyes (9.6%). The mean logMAR visual acuity and mean VF-14 scores improved significantly after IOL exchange (P < .01). Forty-seven patients (90.4%) reported improvement in the subjective quality of vision after IOL exchange. However, after the exchange, visual acuity worsened in 5 patients (9.6%) and subjective quality of vision worsened in 3 patients (5.8%); the VF-14 scores decreased in 5 (14.7%) of the 34 patients tested.

CONCLUSIONS

Visual function and quality of life were better after IOL exchange. However, poor outcomes in some patients mandate an extensive informed consent procedure for clear IOL exchange.

Implantation of Verisyse Phakic Intraocular Lens to Correct Myopic Refractive Error After Penetrating Keratoplasty in Pseudophakic Eyes

PURPOSE

We report 2 cases in which a Verisyse phakic intraocular lens (PIOL) was used to successfully treat high myopia after penetrating keratoplasty (PK) in pseudophakic patients.

METHODS

Case 1 involved a 69-year-old pseudophakic man with a manifest refraction (MR) of -6.50 + 1.75 x 048 and a best spectacle corrected visual acuity (BSCVA) of 20/40 approximately 16 months after PK in the right eye. Case 2 was a 78-year-old pseudophakic man who had an MR of -9.00 + 5.75 x 132 with a BSCVA of 20/100 approximately 24 months after PK in the left eye.

RESULTS

In case 1, 10 months after Verisyse PIOL implantation, the MR was pl +2.00 x 135 with a BSCVA of 20/30. Endothelial cell density (ECD) in this patient decreased from 1926.1 to 815.3 cells/mm over 17 months. In case 2, 24 months after Verisyse PIOL implantation, the MR was -3.25 + 3.50 x 105 with a BSCVA of 20/60. ECD in this patient decreased from 2108.4 to 753.8 cells/mm in 30 months.

CONCLUSION

The Verisyse PIOL may provide an alternative method to correct high myopia for anisometropia in pseudophakic patients after PK. In this report, PIOL implantation was associated with a decrease in ECD. Further studies are required to determine the long-term effects and ultimate safety of PIOL placement on the integrity of the cornea endothelium after corneal transplant in pseudophakic patients.

Investigation and management of an epidemic of Hydroview intraocular lens opacification

BACKGROUND

Opacification of Hydroview posterior chamber intraocular lenses had been prescribed, but many aspects of this complication remain unknown, including its aetiology, clinical features, pathogenesis, prognosis and treatment. This paper describes an epidemic of Hydroview intraocular lens (IOL) opacification.

METHODS

Subjects in whom the Hydroview IOL was implanted were recalled for evaluation of its transparency, assessment of contrast sensitivity (CS) [VCTS (Vistech CO, Dayton, Ohio, USA)] and visual acuity (LogMAR), and analysis of medical and surgical data. The results of IOL exchange in 69 eyes of 67 patients are also presented.

RESULTS

Of 103 patients recalled, 46 (44.6%) and 3 (2.9%) exhibited opacification of the implanted IOL in one and both eyes, respectively. CS was significantly worse in the presence of an opacified IOL (P<0.050), even when Snellen acuity was unaffected. Where the viscoelastic employed during the primary cataract surgery was reliably documented, VISCOAT was used in 100% of cases (43/43), whereas Healonid had not been used in any (0/57) (P<0.0001). Following IOL exchange, visual acuity improved from a mean (+/-SD) of 0.75 (0.41) to 0.4 (0.34) LogMAR.

CONCLUSIONS

The prevalence of Hydroview IOL opacification is associated with the use of VISCOAT in the primary cataract surgery, and there is a biochemically plausible rationale to account for this. Visual acuity and contrast sensitivity are adversely affected by opacification of the Hydroview IOL, but CS to a greater extent. Exchange of opaque IOLs is a visually rewarding procedure.

Perioperative complications of intraocular lens exchange in patients with opacified Aqua-Sense lenses

PURPOSE

To evaluate the perioperative complications of intraocular lens (IOL) exchange in 25 eyes of 22 patients with opacified Aqua-Sense IOLs (Ophthalmic Innovations International).

SETTING

Department of Ophthalmology, University Hospital Aintree, Liverpool, United Kingdom.

METHODS

The study comprised 22 patients (25 eyes) who had previous phacoemulsification and implantation of Aqua-Sense single-piece hydrophilic acrylic IOLs in the capsular bag and developed severe late opacification of the IOL. All patients reported glare and deterioration in vision. The IOLs were explanted and replaced with new lenses. The perioperative complications were evaluated. The best corrected visual acuity (BCVA) before and after surgery was compared.

RESULTS

In 24 eyes, the opacification was complete, involving the optic, haptics, and substance of the IOLs. Uneventful IOL exchange and placement of a new IOL in the bag was achieved in 13 eyes (52%). Complications occurred in the remaining 12 eyes (48%). Ten eyes (40%) developed zonular dehiscence, 4 (16%) of which were managed with anterior chamber IOL implantation. One eye (4%) developed posterior capsule rupture and 1 eye (4%), posterior capsule rupture and zonular dehiscence. The cornea decompensated in 2 eyes (8%). One eye (4%) developed Pseudomonas keratitis. The mean BCVA (decimal scale) before and after IOL exchange was 0.57 +/- 0.24 and 0.60 +/- 0.28, respectively. There was no significant difference in visual acuity between before and after IOL exchange (P=.782, paired t test).

CONCLUSIONS

Explantation of Aqua-Sense IOLs was challenging because of the tight adherence of the optic and haptics to the capsule. Long-term follow-up of patients with Aqua-Sense IOLs should be maintained.

Effect of multipurpose solutions for contact lens care on the in vitro drug-induced spoliation of poly(2-hydroxyethyl methacrylate) in simulated aqueous humour

Drug-induced spoliation of hydrogels as contact lenses or as implants in the anterior eye is a frequent occurrence in clinical practice. This study explores the capacity of three commercial multipurpose solutions for contact lens care to reduce the spoliation of poly(2-hydroxyethyl methacrylate) (PHEMA) specimens exposed to a simulated aqueous humour formulation and to three topical drugs commonly administered after insertion of artificial corneas (Predsol, Optimol and Depo-Ralovera). ReNu MultiPlus (Bausch & Lomb), Complete Blink-N-Cleantrade mark Lens Drops (Allergan) and Complete Protein Remover Tablets dissolved in Complete ComfortPLUS (both from Allergan) were evaluated. All multipurpose solutions were able to dislodge passively the deposits formed on hydrogels in the simulated aqueous and in the presence of Predsol and Optimol, but none were effective against the deposits induced by Depo-Ralovera. A reduction of the calcium content in deposits caused by Predsol and Optimol was confirmed after treatment with the protein remover preparation, while the other multipurpose solutions caused the complete removal of the deposits. In experiments designed to evaluate the preventive action of the multipurpose solutions, no such effects were observed regardless of the drug involved. The prospect of using multipurpose solutions as eye drops following implantation of a hydrogel artificial cornea is a valid alternative for reducing device spoliation, however it appears to depend on the nature of the postoperative medication.

In vitro drug-induced spoliation of a keratoprosthetic hydrogel

PURPOSE

To investigate in vitro the effects of selected drugs on the spoliation of poly(2-hydroxyethyl methacrylate) (PHEMA), a synthetic acrylic hydrogel currently used for the manufacture of a keratoprosthesis, AlphaCor. The experiments were carried out both in the presence of simulated aqueous humor (SAH) and in its absence.

METHODS

Disks of PHEMA were incubated and shaken with 9 commonly prescribed drugs at 37 degrees C in sterile conditions for 1 week. Samples were incubated either in SAH only (controls), in each drug preparation, or in each drug for 1 week followed by 1 week in SAH. The drugs selected for this study were steroids (prednisolone, dexamethasone, fluorometholone, medroxyprogesterone), antiglaucoma drugs (timolol maleate and pilocarpine), and antibiotics (chloramphenicol, cephazolin, and ciprofloxacin), as commercially available formulations. Following incubation, the PHEMA specimens were examined visually and then histologically, after staining with alizarin red for the presence of calcium in the spoliating sediments/deposits.

RESULTS

Although only 5 of the drug formulations (dexamethasone as Maxidex, fluorometholone as FML, pilocarpine as Isopto Carpine, chloramphenicol as Chlorsig, and medroxyprogesterone as Depo-Ralovera) induced spoliation of the hydrogel in the absence of SAH, all drugs induced spoliation after postincubation in SAH, and calcium was detected in the majority of samples. The deposits on the hydrogel specimens incubated first in cephazolin (as Cefazolin-BC), pilocarpine (as Isopto Carpine), and chloramphenicol (as Chlorsig) and then in SAH did not contain calcium, despite its presence in SAH.

CONCLUSIONS

The study appears to confirm our earlier clinical observations that topical medication may play a role in the spoliation of the hydrogel ophthalmic devices. Presence of calcium in the deposits seems to be correlated to the nature of drug. Although the incidence of spoliation in real clinical situations is much lower than suggested by this extreme-case in vitro simulation, topical therapy after implantation of AlphaCor should be carefully considered, kept to the minimum required, and additive-free where possible.

Evaluation of calcification of a hydrogel intraocular lens by optical coherence tomography

We describe 2 cases of calcification of hydrogel intraocular lenses (IOLs) evaluated by optical coherence tomography. Dense or slight surface opacities of hydrogel IOLs were detected initially by slitlamp biomicroscopy in a 55-year-old woman and a 77-year-old woman. The opacities resulted in complaints of hazy vision after uneventful phacoemulsification and IOL implantation. Optical coherence tomography was used to further assess the opacities and showed calcification by high reflectivity on the anterior and posterior IOL surfaces in the first patient and on the anterior surface in the second patient. No abnormal reflectivity was seen on the surface of a hydrophobic acrylic IOL in the second patient's fellow eye. Optical coherence tomography may be useful to detect calcification of a hydrogel IOL.