Systematic review of potential causes of intraocular lens opacification

LONG-TERM OUTCOME OF TRANSSCLERAL FOUR-POINT FIXATION OF AKREOS INTRAOCULAR LENS WITH CLOSED CONTINUOUS-LOOP SUTURE

PURPOSE

To report the long-term clinical outcomes of transscleral four-point fixation of Akreos intraocular lens using a closed continuous-loop suture technique.

METHODS

This was a retrospective, multicenter, interventional case series. Primary outcome measures were best-corrected visual acuity, intraocular pressure, corneal endothelial cell density, and complications with a minimum of 1-year follow-up.

RESULTS

One hundred and ninety-two eyes of 177 patients from two surgical hospital sites were identified. The mean best-corrected visual acuity improved from 0.88 ± 0.74 logarithm of the minimum angle of resolution (Snellen 20/152) preoperatively to 0.42 ± 0.52 logarithm of the minimum angle of resolution (Snellen 20/53) postoperatively ( P < 0.001). The mean preoperative intraocular pressure was 17.51 ± 8.67 mmHg, and the mean postoperative intraocular pressure at final follow-up was 15.08 ± 4.18 mmHg ( P = 0.001). The mean corneal endothelial cell density significantly reduced from 2,259 ± 729 cells/mm 2 to 2077 ± 659 cells/mm 2 , representing a cell loss of 5.73% ( P < 0.001). The intraocular lens was fixed well during follow-up. There were no intraoperative complications noted. Postoperative complications included transient ocular hypertension in 15 eyes (7.81%), hypotony in two eyes (1.04%), retinal detachment in one eye (0.52%), and macular edema in one eye (0.52%).

CONCLUSION

The transscleral four-point fixation Akreos intraocular lens using the closed continuous-loop suture technique was effective and safe with satisfactory visual acuity with a minimum of 1-year follow-up.

Long-term Prevalence of Opacification of a Hydrophylic Acrylic Rotationally Asymmetric Refractive Multifocal Intraocular Lens

PURPOSE

To determine the prevalence of opacification of a hydrophylic intraocular lens (IOL) with hydrophobic coverage and the percentage of explantations required, determining possible risk factors associated with these opacifications.

METHODS

This ambispective study enrolled 575 eyes of 296 patients (age 36 to 87 years) that underwent cataract surgery between 2010 and 2017 with implantation of different models of Lentis Mplus IOLs: LS-312-MF30, LS-313-MF15, LS-313-MF30, LU-313-MF30, and LU-313-MF30T (Oculentis GmbH). Visual, refractive, and slit-lamp biomicroscopic changes were evaluated in a long-term follow-up. The percentage of cases with IOL opacification and the percentage of cases in which IOL explantation was required due to such opacifications were calculated at each visit. Five of the explanted IOLs from this series could be analyzed by scanning electron microscopy (SEM-EDX).

RESULTS

IOL opacification developed in 63 eyes (11.0%). With 95% confidence, the prevalence of IOL opacification was between 842 and 1,401 cases per 10,000 eyes. The time elapsed between surgery and the presence of IOL opacification ranged between 0 and 9.3 years (mean: 4.7 ± 2.2 years). No significant differences in terms of IOL opacification rate were found according to gender (P = .378). No significant differences were found in arterial hypertension, diabetes, hypothyroidism, or hyperthyroidism rates between eyes with or without IOL opacification (P ≥ .053). IOL explantation was needed in 9 eyes (1.57%). SEM-EDX analysis confirmed the presence of rough areas on the IOL surface containing different components, such as calcium, phosphorous, copper, or nitrogen.

CONCLUSIONS

The prevalence of opacification with time in Lentis Mplus IOLs is high, with no systemic risk factors associated with this complication, suggesting that it may be attributable to the material and/or the manufacturing process. [J Refract Surg. 2024;40(2):e98-e107.].

[Hydrophobic surface properties of hydrophilic acrylic lenses do not protect against calcification]

BACKGROUND

Opacification through calcification of hydrophilic acrylic intraocular lenses is a serious complication of cataract surgery, which usually results in explantation of the lens. In the process of calcification, the intraocular lens material plays a crucial role: calcification only occurs in hydrophilic acrylic lenses. Hydrophobic acrylic lenses show no crystal formation within the polymer. Hydrophilic acrylic lenses from some manufacturers have hydrophobic surface properties. The question arises as to what influence these surface properties have on the risk of calcification.

OBJECTIVE

The present study investigated whether the hydrophobic surface properties of hydrophilic acrylic lenses can prevent calcification.

MATERIAL AND METHODS

Using an electrophoretic in vitro model of calcification, two hydrophilic lenses with hydrophobic surface properties were compared to two hydrophilic lenses and a hydrophobic negative control to determine the risk of calcification. The lenses were then analyzed by optical microscopy, Alizarin Red and Von Kossa staining, scanning electron microscopy (SEM) and energy dispersive X‑ray spectroscopy (EDX).

RESULTS

All four hydrophilic lens models showed calcification within the polymer. No difference was found between the hydrophilic lenses and the hydrophilic lenses with hydrophobic surface properties in terms of crystal formation. The hydrophobic negative control showed no calcification.

CONCLUSION

The investigation conducted in this study under standardized conditions could show that hydrophobic surface properties of hydrophilic acrylic lenses do not protect against calcium phosphate crystal formation within the polymer. There also is a risk of calcification in these lens models.

FIL SSF intraocular lens opacification after pars plana vitrectomy with gas tamponade for traumatic lens luxation and retinal detachment: a case report and literature review

BACKGROUND

To report a case of sutureless scleral-fixated hydrophilic intraocular lens (FIL SSF IOL, Soleko, Italy) opacification following pars plana vitrectomy surgery using sulfur hexafluoride (SF6) for traumatic lens luxation associated with retinal detachment.

CASE PRESENTATION

A 77-year-old woman was referred to our emergency department after blunt trauma in her right eye. At the ophthalmic evaluation, visual acuity was hand movement, biomicroscopy showed pseudoexfoliation syndrome and a traumatic lens luxation in the vitreous chamber. The patient underwent pars plana vitrectomy, subluxated cataract explantation, and FIL SSF IOL implant. During surgery, an inferior retinal detachment was encountered, requiring 20% SF6 gas tamponade. No adverse events were encountered. One month postoperatively, visual acuity (BCVA) improved to 0,3 logMAR. At the 3-month follow-up, the patient presented with BCVA of 0,5 logMAR, and biomicroscopy showed a minimal IOL opacification. Six months postoperatively, BCVA decreased to 1.0 logMAR, and diffuse, IOL opacification was noted at slit lamp examination. The patient refused any other surgical intervention for IOL exchange.

CONCLUSIONS

Although hydrophilic IOL opacification gas related is known, to the best of our knowledge, this is the first case reported in the literature of FIL SSF IOL opacification after pars plana vitrectomy with gas tamponade for retinal detachment.

Opacification of Hydrophilic Acrylic Intraocular Lenses: Overview of Laboratory Methods for Histological Analysis and Replication of IOL Calcification

Opacification of intraocular lenses (IOLs) due to material changes is a serious complication that can compromise the good visual outcomes of uncomplicated cataract surgery. In hydrophobic acrylic IOLs, opacification can result from glistening formation, while in hydrophilic acrylic IOLs, there is a risk of calcification due to the formation of calcium phosphates within the polymer. Over time, various methods have been developed to investigate calcification in hydrophilic acrylic IOLs. The aim of this article is to provide an overview of standard histological staining and models used to simulate IOL calcification. Histological staining can be used to detect calcification and assess the extent of crystal formation. The development of in vivo and in vitro replication models has helped to identify the underlying pathomechanisms of calcification. In vivo models are suitable for assessing the biocompatibility of IOL materials. Bioreactors as an in vitro model can be used to investigate the kinetics of crystal formation within the polymer. The replication of IOL calcification under standardized conditions using electrophoresis allows for the comparison of different lens materials with respect to the risk of calcification. The combination of different analytical and replication methods can be used in the future to further investigate the pathomechanisms of calcium phosphate crystal formation and the influence of risk factors. This may help to prevent calcification of hydrophilic acrylic IOLs and associated explantation and complications.

Combined Temporary Pupilloplasty and DSEK in an Eye With a Hydrophilic Acrylic Intraocular Lens to Prevent Opacification: A Case Report

PURPOSE

The aim of this study was to describe a case of temporary pupilloplasty during Descemet stripping endothelial keratoplasty to prevent opacification of a hydrophilic acrylic intraocular lens (IOL).

METHODS

A 60-year-old man presented with corneal edema in the left eye after a traumatic cataract removal and scleral suture fixation of a hydrophilic acrylic IOL (Akreos, Bausch + Lomb, Bridgewater, NJ). Descemet stripping endothelial keratoplasty with temporary pupilloplasty was performed. The pupilloplasty was lysed with neodymium:YAG laser on postoperative day 5 after the air bubble was no longer present.

RESULTS

At 1 year after surgery, the patient did not develop IOL opacification despite the intracameral air used during the surgery.

CONCLUSIONS

Opacification of hydrophilic acrylic lenses is a visually significant complication of intracameral gas from endothelial keratoplasty. Our case demonstrates the potential to prevent IOL opacification in a patient with a hydrophilic acrylic IOL by using temporary pupilloplasty.

Wave-like calcification on the posterior surface of an acrylic hydrophilic bag-in-the-lens (BIL) implant

Purpose

To report secondary opacification of a hydrophilic bag-in-the-lens (BIL) which is a rare manifestation that can happen years after initial surgery.

Observations

We describe a case of a prominent wave-like, rippled opacification on the posterior surface of the BIL. The opacification was composed of calcium deposits and seems to start in the periphery as a ring and progresses to the centre of the posterior surface. Due to the specific design of the BIL, there is direct contact between the BIL and the posterior chamber, both with the space of Berger, and the anterior hyaloid, particularly in this very hyperopic eye. Conclusions and importance: Abnormal fluid flow and stagnation in an unusual retrolenticular space is a possible explanation for this unusual pattern of posterior surface opacification.

Development of a standardized in vitro model to reproduce hydrophilic acrylic intraocular lens calcification

Opacification through calcification of hydrophilic acrylic intraocular lenses (IOL) is a severe complication after cataract surgery. Causing symptoms that range from glare through to severe vision loss, the only effective therapy is explantation of the opacified IOL so far. Although IOL calcification is a well-described phenomenon, its pathogenesis is not fully understood yet. The purpose of the current study was to develop a laboratory model to replicate IOL calcification. Calcification could be reproduced using a horizontal electrophoresis and aqueous solutions of calcium chloride and disodium hydrogen phosphate. The analysis of the in vitro calcified IOLs was performed using light microscopy, Alizarin Red and Von Kossa staining, scanning electron microscopy, energy dispersive x-ray spectroscopy and electron crystallography using transmission electron microscopy and electron diffraction. The presented laboratory model could be used to identify hydrophilic IOLs that are at risk to develop calcification and to assess the influence of associated risk factors. In addition, it can serve as a research tool to further understand this pathology.

Opacification of refractive bifocal intraocular lens in one month: Three case reports

RATIONALE

Multifocal intraocular lenses (IOLs) are used widely. However, the discovery of LS-313 MF15/30 (Oculentis B.V.) opacity during surgery has not yet been reported. This article reports 3 cases of LS-313 MF15/30 (Oculentis B.V.) IOL opacity found during cataract surgery implantation within 1 month.

PATIENT CONCERNS

Three patients underwent cataract surgery, and opacification of their IOL (LS-313 MF15/30, Oculentis B.V.) was found intraoperatively.

DIAGNOSIS

The patient was diagnosed with a postoperative intraocular opacity.

INTERVENTIONS

In case 1, the surgeon scrubbed the IOL with intraocular perfusion fluid and a gelatin sponge swab to reduce opacity in the central optical area of the IOL and then implanted it into the capsule bag. In case 2, the surgeon used the infusion-aspiration polishing mode for cleaning. To avoid IOL wear and bag damage, washing was stopped when turbidity in the center of the optical area was reduced. In case 3, we learned from our previous experience that the surgeon cut the IOL into 2 pieces and moved it out at the main incision, which was replaced and implanted with a brand new IOL, after the implanted IOL was again found cloudy.

OUTCOMES

In case 1, more than 10 months after the surgery, the IOL was restored to transparency, no obvious eye discomfort was noted, and uncorrected visual acuity was 20/25. In case 2, the patient's IOL surrounding area was still partially turbid after more than 10 months of follow-up. In case 3, the patient's uncorrected visual acuity on postoperative day 1 was 20/20, and the best-corrected visual acuity was 20/20.

LESSON

There are many reasons for the opacification of the IOL. In addition to the patient's own factors, the material, production, and packaging of the IOL, as well as the influence of external environmental temperature, the influence of the IOL implant instrument should not be ignored and needs to be considered.

Intraocular Bag-in-the-Lens Exchange: Indications, Outcomes and Complications

PURPOSE

To report the indications, outcomes, and complications regarding the Bag-in-the-lens (BIL) intraocular lens (IOL) exchanges over a period of 13 years in a tertiary ophthalmologic centre.

SETTING

Department of Ophthalmology of the University Hospital of Antwerp (UZA).

DESIGN

Observational retrospective study.

PATIENTS AND METHODS

Between 2003 and 2020, 12 176 patients were operated using the BIL technique. We included adult patients who underwent an intraocular BIL exchange and recorded the demographics, indications, outcomes, and complications.

RESULTS

Fifty-nine eyes of 59 patients who underwent a BIL exchange between 2007 and 2020 were included (0.48%). The mean age was 61.15 ±13.53 years. The mean time between primary surgery and IOL exchange was 25.73 ± 41.88 months. The main indication for explantation was refractive surprise mostly related to the patients' risk factors e.g. preoperative corneal and refractive surgery. The mean preoperative uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) were 0.36 ± 0.24 and 0.79 ± 0.24 respectively. The postoperative 1 month-UDVA and CDVA were 0.66 ± 0.28 and 0.86 ± 0.19 respectively. The improvement in UDVA was statistically significant (<0.0001). The most common peroperative complication was damage to the anterior hyaloid in 9 eyes (15%), which did not prohibit reimplantation of a secondary BIL.

CONCLUSIONS

BIL to BIL exchange is an viable and successful technique that provides good refractive results with few, manageable complications. Because of the tertiary profile of our centre with referral of complex cases, BIL was our preferred IOL in patients at risk of postoperative refractive surprise.

Clinical features of red blood cell-coated intraocular lens after breakthrough vitreous hemorrhage secondary to neovascular age-related macular degeneration

PURPOSE

To investigate the incidence and clinical features of red blood cell (RBC)-coated intraocular lens (IOL) in breakthrough vitreous hemorrhage (VH) with subretinal hemorrhage (SRH) secondary to neovascular age-related macular degeneration (nAMD).

SETTING

Seoul National University Bundang Hospital, Seongnam, Korea.

DESIGN

Retrospective cohort analysis.

METHODS

A total of 30 patients diagnosed as breakthrough VH with SRH in nAMD who underwent pars plana vitrectomy were included in this study. Demographics and clinical characteristics of the subjects, visual acuities, and SRH sizes measured as disc diameters were analyzed. The correlation analysis between SRH size and absorption duration of RBC-coated IOL were performed.

RESULTS

Out of 30 eyes in 30 patients, RBC-coated IOLs were observed in 11 patients (37%). Appearance of RBC-coated IOLs was noted 1 month postoperatively, and the mean duration of SRH absorption was 8.6 ± 2.6 months. SRH sizes were significantly different between eyes with RBC-coated IOL and clear IOL (62.8 ± 20.7 vs 27.4 ± 14.2, P < .001). There was definite correlation between SRH size and absorption duration of RBC-coated IOL (correlation coefficient 0.899, P < .001, R2 = 0.831). There were no statistically significant differences according to age, sex, laterality, underlying medical conditions, preoperative lens status, history of antivascular endothelial growth factor treatment, and visual acuities. The degenerated RBC on the surface of IOL was confirmed by electron and light microscopy.

CONCLUSIONS

RBC-coated IOL could develop after vitrectomy surgery for breakthrough VH with massive SRH secondary to nAMD, and it can be confused with IOL opacification. Because it spontaneously disappears gradually, observation without IOL removal is warranted.

Analysis of opacification patterns in intraocular lenses (IOL)

Objective

Intraocular lens (IOL) opacification may cause severe visual impairment. The pathogenesis remains unclear. The aim of this study was to analyse opacification patterns in different IOLs. Therefore, this multicentre, retrospective, observational study was conducted at Ludwig-Maximilians-University, Munich, Germany and University-Hospital Basel, Switzerland.

Methods and analysis

In this study, 75 opacified IOLs were identified and classified after extraction. Macroscopical photo documentation, light and electron microscopic analysis were done.

Results

68 acrylic-hydrophilic single-piece-IOLs, 1 acrylic-hydrophilic 3-piece-IOL, 6 acrylic-hydrophobic 3-piece-IOLs were extracted. The dataset comprised IOLs known for opacification and IOLs not having been reported yet. 67 IOLs showed a fine-granular and 8 IOLs a crust-like opacification pattern. According to literature, 62 of the fine-granular opacified IOLs were graded into type 1 (processing/packaging-induced primary opacification) and 13 into type 2 (secondary opacification of unknown aetiology). The anterior surface of the IOLs was affected in all 75 IOLs, the posterior surface only in 23 cases. Of all 67 fine-granular IOLs, 43 had a central defect and 21 had a zone without opacification (clear islet).

Conclusion

In our series, the morphology of IOL opacification did not follow the existing pathogenetic classification that strictly discriminates between primary and secondary causes. Fine-granular IOL opacification occurs with similar patterns in both type 1 and type 2 IOL opacification, while a crust-like pattern was only detected in type 2 IOL opacifications. Consequently, susceptibility of an IOL to opacification is caused by a multifactorial combination of material and processing properties as well as individual (pathological) conditions of the patient.

Physicochemical Analysis of Sediments Formed on the Surface of Hydrophilic Intraocular Lens after Descemet's Stripping Endothelial Keratoplasty

An intraocular lens (IOL) is a synthetic, artificial lens placed inside the eye that replaces a natural lens that is surgically removed, usually as part of cataract surgery. The opacification of the artificial lens can be related to the formation of the sediments on its surface and could seriously impair vision. The physicochemical analysis was performed on an explanted hydrophilic IOL and compared to the unused one, considered as a reference IOL. The studies were carried out using surface sensitive techniques, which can contribute to a better understanding of the sedimentation process on hydrophilic IOLs’ surfaces. The microscopic studies allowed us to determine the morphology of sediments observed on explanted IOL. The photoelectron spectroscopy measurements revealed the presence of organic and inorganic compounds at the lens surface. Mass spectroscopy measurements confirmed the chemical composition of deposits and allowed for chemical imaging of the IOL surface. Applied techniques allowed to obtain a new set of information approximating the origin of the sediments’ formation on the surface of the hydrophilic IOLs after Descemet’s stripping endothelial keratoplasty.