Hydrophilic acrylic intraocular lens exchange: Five-year experience

Long-Term Outcome and Complications of IOL-Exchange

Purpose

To describe the long-term outcome after intraocular lens (IOL) exchange for IOL-opacification with a focus on any occurring complications.

Patients and Methods

Patients with an IOL exchange for opacified IOLs (Lentis LS-502-1) were identified. Medical records and information from the treating ophthalmologists were reviewed. Visual outcomes and any occurring complications after the IOL exchange were analyzed.

Results

IOL exchange was performed in 48 eyes of 46 patients and significantly improved best-corrected distance visual acuity from 0.42 ± 0.32 logMar (mean ± SD) in opacified lenses to 0.25 ± 0.28 logMar after IOL exchange. Nine of the 48 eyes (19%) underwent 11 further surgical procedures for complications due to four indications: IOL dislocation (n = 2, 4%), retinal detachment (RD) (n = 6, 12%), epiretinal membrane (n = 2, 4%), and pupillary block (n = 1, 2%). Three eyes (6%) developed a temporarily elevated intraocular pressure. Temporary postoperative cystoid macular edema was found in 2 eyes (4%).

Conclusion

IOL exchange can restore vision owing to IOL opacification in most cases. Nonetheless, IOL exchange is not an easy or risk-free procedure. This may lead to sight-threatening complications, even in eyes without predisposing ocular comorbidities.

Imaging Function and Relative Light Transmission of Explanted Opacified Hydrophilic Acrylic Intraocular Lenses

We evaluated the influence of intraocular lens (IOL) opacification on the optical performance of explanted hydrophilic acrylic IOLs. We performed a laboratory analysis of 32 Lentis LS-502-1 (Oculentis GmbH, Berlin, Germany) IOLs, explanted due to opacification, in comparison with six clear unused samples of the same IOL model. Using an optical bench setup, we obtained modulation transfer function (MTF), Strehl ratio, two-dimensional MTF, and United States Air Force (USAF) chart images. In addition, we assessed light transmission through the IOLs. The MTF values of opacified IOLs at 3-mm aperture were similar to those of clear lenses, with the median (interquartile range) values of 0.74 (0.01) vs. 0.76 (0.03) at the spatial frequency of 50 line pairs per millimeter in clear and opacified IOLs, respectively. The Strehl ratio of opacified lenses was not lower than that of clear lenses. The USAF-chart analysis showed a considerable reduction in brightness in opacified IOLs. The median (interquartile range) relative light transmission of opacified IOLs in comparison to clear lenses was 55.6% (20.8%) at the aperture size of 3 mm. In conclusion, the explanted opacified IOLs had comparable MTF values to those of clear lenses but significantly reduced light transmission.

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.

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.

Intraocular lens explantation following cataract surgery: Indications, techniques, and video demonstrations

As techniques for modern cataract surgery have expanded and premium intraocular lens (IOL) use is now widespread, patient expectations are high. The need for IOL explantation, whilst still low, remains an ongoing issue. Intraocular lens explantation can be challenging for a number of reasons and as such we have introduced an additional technique to add to the surgeon's repertoire. Bimanual haptic stripping of fibrosis at the specific area where the haptic is adherent to the capsular bag is an effective strategy to aid in dissection of haptics without compromising the capsule or zonules. Given the challenges associated with IOL explantation, newly designed IOLs need to avoid these "sticking points" at which the IOLs interact with the fibrosed capsule. Techniques we have evolved and which are described below should assist anterior segment surgeons to facilitate IOL removal in an efficient and safe way.

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.

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.

Intraocular lens exchange-removing the optic intact

Current practice for intraocular lens (IOL) exchange is to cut the optic of the posterior chamber intraocular lens (PCIOL) prior to removing it. Great care must be taken during this maneuver to avoid a posterior capsular tear. Removing the haptics from the fibrosed capsule can also be hazardous, as it may result in zonular stress and dehiscence. A technique is described for performing foldable (one-piece acrylic) IOL removal without cutting the optic. Careful visco-dissection of the haptics with a low viscosity ophthalmic viscosurgical device (OVD) in the fibrosed peripheral capsular tunnel avoids zonular or capsular stress. Internal wound enlargement permits foldable IOL removal in one piece, whilst preserving a self-sealing sutureless corneal wound. This technique may enhance the safety and efficacy of foldable IOL exchange.

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.

Late corneal edema due to retained foldable lens fragment

Late onset of corneal edema after cataract surgery is an unusual complication. We report a case of corneal edema presenting one month after cataract surgery. During implantation of the foldable lens, one haptic of the intraocular lens fractured at the optic haptic junction. This caused lens decentration, necessitating an intraocular lens exchange ten days later. The patient was recovering well but presented again two weeks later with a drop in vision due to corneal edema. A retained haptic of the intraocular lens was seen in the inferior anterior chamber angle. After surgical removal of the retained haptic the corneal edema fully resolved. Retained intraocular lens fragments can cause corneal endothelial damage, which may be reversible with an early diagnosis and intervention.

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.

Hydrophilic acrylic intraocular lens clouding: a clinicopathological review

PURPOSE

An analysis is made of a serious late complication (opacification) of different models of hydrophilic acrylic intraocular lenses (IOLs).

METHODS

Seven lenses were explanted from seven patients treated for cataracts with phacoemulsification and implantation of different types of hydrophilic acrylic IOLs (five SC60B-OUV from MDR, one Aquasense from OII, and one H60M Hydroview lens from Bausch & Lomb) who developed important vision impairment in the late postoperative period (1 to 3 years) due to lens opacification. The explanted lenses were subjected to exhaustive study involving photographic analysis, scanning electron microscopy, and energy dispersive X-ray spectroscopy.

RESULTS

Light and scanning electron microscopy revealed diffuse, variable-size granular deposits within the optic of the SC60B-OUV lens, and on the anterior and posterior optic surfaces of the H60M Hydroview lens, though without affecting the haptics in any of the models. Dispersive energy X-ray spectroscopy of the deposits revealed the presence mainly of calcium and phosphorus salts.

CONCLUSIONS

Hydrophilic acrylic IOL opacification is a serious late complication of unknown etiology. The condition is more frequent among diabetic patients, and the only management option is IOL explantation and replacement with a lens of some other material. More frequent and longer follow-up is required of those patients wearing lenses for which cases of opacification have been documented, particularly in the presence of predisposing factors (diabetes, uveitis). Caution is required with new lenses, avoiding their generalized use until they have successfully passed the test of time.

Noninvasive identification of different intraocular lenses using Raman spectroscopy in porcine eyes

PURPOSE

To develop a noninvasive technique for identifying the specific type of intraocular lens (IOL) implanted in porcine eyes.

SETTING

Department of Ophthalmology, University of Ulsan College of Medicine, Asan Medical Center, and Department of Chemistry Education, Seoul National University, Seoul, Korea.

METHODS

A confocal Raman spectroscopy system was used to identify various acrylic (AcrySof SA60AT [Alcon], Sensar AR40e [Advanced Medical Optics], I-Flex [I-Medical Intraocular Lenses]) and silicone (ClariFlex, [Advanced Medical Optics]) IOLs implanted in enucleated pig eyes. Confocal Raman spectra of IOLs were obtained by photoexcitation using the 514.5 nm line from an argon-ion laser, with a power of 1 mW at the sample and an acquisition time of 10 to 100 seconds.

RESULTS

All IOLs, including those composed of acrylic optic material from different manufacturers, exhibited distinct spectral peaks before and after implantation in pig eyes.

CONCLUSION

Confocal Raman spectroscopy may represent a novel method for obtaining specific information about implanted IOLs through direct and noninvasive confocal observation of spectral characteristics.