Calcification of hydrophilic acrylic intraocular lenses associated with intracameral air injection following DMEK

Descemet membrane endothelial keratoplasty combined with presbyopia-correcting and toric intraocular lenses - a narrative review

Fuchs endothelial corneal dystrophy (FECD) is the leading indication for EK and may coexist with cataract and presbyopia. Notably, the outcomes of phacoemulsification in FECD patients are not as favorable as those in eyes without this condition. Historically, only monofocal intraocular lenses (IOLs) were recommended for these patients. However, recent reports have described the implantation of Premium-IOLs (such as Multifocal IOLs, Enhanced Depth of Focus IOLs, and Toric IOLs) in FECD eyes undergoing cataract surgery and Descemet membrane endothelial keratoplasty (DMEK). While the results are encouraging, they are not as optimal as those from unoperated eyes, especially when comparing simultaneous procedures to sequential ones. It's advised to perform the DMEK first to improve the accuracy of IOL calculations. Still, even successfully operated eyes may experience secondary graft failure or graft rejection after DMEK. The success rate of a secondary DMEK is typically lower than that of the initial procedure. Furthermore, if the postoperative thickness after DMEK is less than anticipated, laser enhancements might not be an option. There's a pressing need for more controlled and randomized clinical trials to ascertain the safety and effectiveness of Premium-IOLs for FECD eyes. This narrative review aims to collate evidence on the use of Premium IOL technologies in eyes receiving EK and to underscore key points for surgeons performing EK combined with cataract surgery.

Late postoperative opacification of a new type hydrophilic acrylic intraocular lens

Background

To report the clinical consequences and laboratory characteristics of late postoperative opacification of a hydrophilic acrylic intraocular lens (US-860UV IOL) as well as the prognosis of IOL replacement.

Methods

Forty medical records (42 eyes) of patients with US-860UV IOL opacification reporting decreased or lost vision who underwent IOL explantation between 2017 and 2019 were reviewed. Explanted IOLs were analyzed by slit-lamp examination, confocal microscopy, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) at the Shandong Key Laboratory of Ophthalmology, Shandong Eye Institute, Shandong First Medical University, and Qingdao University of Science and Technology, Qingdao, China.

Results

The mean age of the 40 patients was 74.83 ​± ​7.57 (63-92) years. The mean interval between cataract surgery and diagnosis of opacification was 32.38 ​± ​8.76 (17-48) months. Systemic diseases were found without statistical correlations, the most frequent being arterial hypertension, coronary heart disease, and diabetes mellitus. Visual acuity improved from 1.42 ​± ​1.03 to 0.31 ​± ​0.16 (logMAR) after IOL replacement. SEM, EDS and alizarin red staining showed uniformly distributed, diffuse, milk-white opacification, with calcium and phosphorus deposits on the optic and haptic surfaces that could be dissolved in 1% HCl.

Conclusions

Calcium and phosphorus deposition was the main cause of hydrophilic acrylic US-860UV IOL opacification. IOL replacement can safely and effectively improve the visual acuity of patients.

The effect of hypotensive drugs on intraocular lenses clarity

OBJECTIVES

To assess the effect of hypotensive drugs on light absorbance, discoloration, opacification and precipitate formation of IOLs.

METHODS

In this laboratory study, four types of IOLs (two hydrophilic-acrylic-L1 and L2, and two hydrophobic-acrylic-B1 and B2) were soaked in solutions containing Timolol-maleate 0.5%, Dorzolamide 2%, Brimonidine-tartrate 0.2%, Latanoprost 0.005%, Brimonidine-tartrate/Timolol-maleate 0.2%/0.5% and Dorzolamide/Timolol-maleate 2%/0.5%. Non-treated IOLs and IOLs soaked in balanced salt solution (BSS) served as controls. All Treated lenses were sealed in containers and placed in an oven at 82 degrees Celsius for 120 days. Each IOL was examined using four different techniques: light microscopy imaging, light absorbance measurements at 550 nanometers through the optic's center, assessment of by a scanning electron microscope (SEM), and energy dispersive Xray spectrometry (EDX).

RESULTS

Ninety-eight IOLs were included. All BSS-soaked IOLs appeared clear with no significant discoloration or precipitate-formation. Light absorbance in these lenses was comparable to that of non-soaked, non-heated IOLs. No calcium or phosphate were detected in either of these groups. Light absorbance differed significantly between the four treated IOL types. The drops most affecting light absorbance differed between IOLs. Gross examination revealed brown and yellow discoloration of all IOLs soaked in Dorzolamide and Brimonidine-tartrate solutions, respectively. SEM demonstrated precipitates that differed in size, morphology and distribution, between different IOL-solution combinations. EDX's demonstrated the presence calcium and phosphor in the majority of precipitates and the presence of sulfur in brown discolored IOLs.

CONCLUSIONS

In vitro, interactions between hypotensive drugs and IOLs induce changes in light absorbance, discoloration and precipitate formation.

Intraocular Lens Calcification After Pseudophakic Endothelial Keratoplasty

PURPOSE

To determine the incidence and to document risk factors for intraocular lens (IOL) calcification after pseudophakic endothelial keratoplasty.

METHODS

We retrospectively studied 2700 consecutive penetrating, anterior lamellar and endothelial keratoplasties carried out between December 1992 and June 2022 at the National Eye Hospital, Paris, France.

DESIGN

Retrospective cohort study.

RESULTS

All IOL calcification cases were associated with endothelial keratoplasty. Out of 588 endothelial keratoplasty procedures, 576 eyes were pseudophakic at the end of surgery. Fourteen cases of IOL calcification were observed during follow-up. The cumulative incidence of IOL calcification after endothelial keratoplasty was 4.5%±1.3% at 60 months. Hydrophilic acrylic IOL material (P < .001) and use of SF₆ for anterior chamber tamponade (P = .001) were significantly and independently associated with the cumulative incidence of IOL calcification.

CONCLUSION

The incidence of IOL calcifications seems to be around 5%. Ophthalmologists should avoid hydrophilic acrylic IOLs in patients with endothelial disorders. When the patient already has a hydrophilic IOL, SF₆ should be avoided. The only effective treatment is IOL exchange.

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.

Descemet membrane endothelial keratoplasty: Update on preoperative considerations, surgical techniques, and outcomes

Descemet membrane endothelial keratoplasty (DMEK) is the closest to the physiological replacement of endothelial cells. In the initial years, the technique was surgically challenging. Over the years, with better understanding and modifications in the surgical steps, the technique has evolved as an alternative to more popular procedure Descemet stripping endothelial keratoplasty. The article highlights the various preoperative, intraoperative, and postoperative nuances of DMEK. Additionally, it summarizes the various comparative and noncomparative studies on DMEK outcomes.

Effects of uncomplicated Descemet membrane endothelial keratoplasty on the central retinal thickness

Purpose

To determine retinal thickness (RT) changes and the incidence of macular edema after uncomplicated Descemet membrane endothelial keratoplasty (DMEK-ME) in patients without ME risk factors.

Methods

In this retrospective study, 107 pseudophakic eyes of 74 patients with Fuchs endothelial dystrophy (FED) (79.4%) or bullous keratopathy (BK) (20.6%) underwent DMEK surgery between 2016 and 2019 at the Department of Ophthalmology, RWTH Aachen University. Patients with intra- or postoperative complications as well as pre-existing risk factors for ME were excluded. Macular spectral-domain optical coherence tomography (SD-OCT) and best spectacle-corrected visual acuity (BSCVA) measurements were performed before, 1 week, 1 month, and 6 months after surgery. Retinal thickness (RT) was analyzed in the central foveal 1 mm (CSF), parafoveal 3 mm and 6 mm subfield.

Results

Eight eyes (7.5%) developed DMEK-ME 1 month after surgery. Six DMEK-ME eyes (75%) were rebubbled, compared with 31.3% (31 of 99; P = 0.02) of the non DMEK-ME eyes. DMEK-ME eyes had a significantly thicker CSF 1 month after surgery (432.0 ± 97.6 μm) compared with non-DMEK-ME eyes (283.7 ± 22.2 μm; P = 0.01). The other subfields and time points showed no significant RT changes. DMEK-ME significantly impaired BSCVA (0.38 ± 0.92 logMAR) only 1 month after surgery in comparison to the non DMEK-ME eyes (0.23 ± 0.87 logMAR, P = 0.015).

Conclusion

Excluding systemic and surgery-related risk factors, rebubbling increases the risk of DMEK-ME. Performing a CSF scan 1 month after surgery, particularly in rebubbled eyes, efficiently detects DMEK-ME and allows the prompt initiation of treatment, e.g., topical corticosteroid and non-steroidal (NSAID) eye drops.

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.

Long-term Results of a Combined Procedure of Cataract Surgery and Descemet Membrane Endothelial Keratoplasty With Stromal Rim

PURPOSE

To evaluate the long-term results of combining cataract surgery, intraocular lens (IOL) implantation, and Descemet membrane endothelial keratoplasty with peripheral stromal support (DMEK-S).

METHODS

The outcomes of 107 eyes of 37 patients who had undergone a combination of cataract surgery, IOL implantation, and DMEK-S between October 2007 and February 2015 were retrospectively evaluated. The average follow-up duration was 18.2 ± 18.3 months (range, 6-84 months). Changes in uncorrected and corrected distance visual acuity, spherical equivalent, and corneal endothelial cell density were analyzed. Intraoperative and postoperative complications were also recorded.

RESULTS

The mean logMAR uncorrected distance visual acuity improved from 0.92 ± 0.60 preoperatively to 0.33 ± 0.33, 0.28 ± 0.25, 0.24 ± 0.20, and 0.27 ± 0.27 at 6, 12, 24, and 36 months postoperatively (P < 0.001), respectively. The mean logMAR corrected distance visual acuity improved from 0.62 ± 0.65 preoperatively to 0.17 ± 0.29, 0.13 ± 0.21, 0.07 ± 0.16, and 0.11 ± 0.23 at 6, 12, 24, and 36 months postoperatively (P < 0.001), respectively. The mean endothelial cell density decreases were 50.7% ± 21.1%, 50.8% ± 19.8%, 60.7% ± 16.6%, 62.2% ± 11.8%, and 61.8% ± 20.0% at 6, 12, 24, 36, and 48 months after surgery, respectively. Similar trends, although with slightly better visual outcomes, were found in the subgroup of patients without other eye diseases. The mean final deviation from intended spherical equivalent was 0.77 ± 1.19 D, representing a hyperopic shift.

CONCLUSIONS

A combined procedure of cataract surgery, IOL implantation, and DMEK-S is an effective method of treatment in patients with combined corneal disease and cataract, maintaining visual rehabilitation in the long term. Future developments should be performed to minimize the incidence of complications.

Variation in intraocular lens calcification under different environmental conditions in eyes with supplementary sulcus-supported lenses

Purpose

Analysis of explanted intraocular lenses (IOLs) from pseudophakic eyes with supplementary sulcus-supported IOLs.

Methods

In this laboratory investigation, ten supplementary and capsular bag IOLs were analyzed. All lenses were received between January 2012 and March 2018. Explants were examined morphologically with histological and electron microscopic techniques and patients’ medical history was evaluated. Additionally, we used a technique new to this field: Transmission Electron Microscopy and electron diffraction pattern analysis was performed to investigate the structure of the opacifying crystals in detail.

Results

Eleven lenses were explanted due to IOL opacification from seven polypseudophakic eyes: In three cases the supplementary lens calcified, in three cases the capsular bag IOL (both lenses analyzed) and in one case both IOLs (only the supplementary was received). Additional surgical procedures and comorbidities included pars plana vitrectomy or Descemet stripping endothelial keratoplasty and diabetes mellitus. For each opacified lens, a varying layer of a Calcium phosphate beneath the optic surface was apparent. Crystal characterization revealed its composition to be Hydroxyapatite.

Conclusions and Importance

We report on a series of secondary calcification in lenses explanted from polypseudophakic eyes. In some cases, calcification occurred in the capsular bag lens, in other cases in the supplementary lens, or in both. The severity of the morphological change could be related to the comorbidities and the presence of surgery subsequent to the lens implantations. Detailed morphology of the opacifying crystals was revealed.

•

Intraocular lenses exhibited calcification in a series of polypseudophakic eyes.

•

Pathology occurred in the capsular bag lens, the supplementary lens, or in both.

•

Calcification was associated with different environmental factors.

•

Depending on the factor, morphology and pattern of the opacity differed.

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Transmission Electron Microscopy revealed the opacifying crystals' ultrastructure.

Assessment of straylight and the modulation transfer function of intraocular lenses with centrally localized opacification associated with the intraocular injection of gas

PURPOSE

To assess the optical quality of intraocular lenses (IOLs) explanted because of opacification after the intraocular injection of gas.

SETTING

David J. Apple Laboratory, Heidelberg, Germany.

DESIGN

Experimental study.

METHODS

Four hydrophilic acrylic IOLs were studied, each with a centrally localized round opacification pattern associated with the intraocular use of gas. Laboratory analysis included gross examination with a light microscope, followed by alizarin and von Kossa staining. Optical quality was assessed by examining the modulation transfer function (MTF) and straylight. Results were compared with those of a control IOL and normative data for straylight of the crystalline lens. The following parameters were derived from image analysis: opacified surface fraction, light loss in the opacified surface, and the area and number of granules. The relationship between straylight increase and those parameters was studied.

RESULTS

Fine granules were identified on the IOL surface and subsurface. The granules stained positive for calcium, and the MTF levels of 2 IOLs dropped markedly. The other 2 showed relatively minor changes. The straylight was extremely increased in 3 IOLs up to (and above) a level of that of a cataractous lens. A proportional relationship was found between straylight and the morphological parameters from image analysis.

CONCLUSIONS

Intraocular lenses with centrally localized opacification have a strong potential for deteriorating optical performance. However, the optical quality might differ depending on the morphology of opacification. A serious straylight increase was found in most of these IOLs, suggesting that affected patients may suffer from glare-related symptoms.

Opacification of hydrophilic intraocular lenses associated with vitrectomy and injection of intraocular gas

Objective

To report 11 cases of intraocular lens (IOL) opacification after pars plana vitrectomy (PPV) involving intravitreal gas injection.

Methods and analysis

Eleven cases of hydrophilic IOLs that opacified following PPV with intravitreal gas injection are described. Eight IOLs were explanted and analysed by light microscopy and scanning electron microscopy. Staining with alizarin red and von Kossa stains, as well as energy dispersive X-ray spectroscopy (EDX) were performed. Three IOLs were not explanted. The surgeons attached the clinical data.

Results

The IOLs were hydrophilic acrylic produced by six manufacturers. Six patients underwent primarily phacoemulsification with IOL implantation. PPV with intravitreal gas injection was performed 3 months–6 years afterwards. The other five patients underwent combined phacoemulsification with IOL implantation and PPV with intravitreal gas injection. IOL opacification was recorded 1 month –6 years after PPV. In eight patients, the IOLs were explanted 1 month–9 years after opacification was noticed. In three patients, the opacified IOL was not explanted. IOLs had opacified mainly anteriorly at the pupillary entrance or capsulorhexis opening. Light microscopy demonstrated granular surface deposits on the IOLs that stained positive for calcium by alizarin red and von Kossa stains. EDX analysis of the deposits detected calcium and phosphorus.

Conclusions

Hydrophilic acrylic IOLs can opacify due to calcium deposition after PPV and intravitreal gas injection and may require IOL explantation. A hydrophobic IOL may be preferred when a simultaneous phacoemulsification and vitrectomy with intravitreal gas is performed.

Material Analysis and Optical Quality Assessment of Opacified Hydrophilic Acrylic Intraocular Lenses After Pars Plana Vitrectomy

PURPOSE

Explanted hydrophilic intraocular lenses (IOLs) with clinically significant opacification after pars plana vitrectomy (PPV) were assessed for material change and optical quality, in an in vitro laboratory study.

DESIGN

Retrospective observational case series.

METHODS

Ten opacified IOLs after PPV with intraocular gas injection were analyzed in a laboratory setting. Analyses included evaluation of patients' medical history, optical quality assessment, light microscopy, histologic staining, scanning electron microscopy, and energy dispersive x-ray spectroscopy.

RESULTS

In all 10 IOLs a thin layer of calcium phosphate that had accumulated underneath either the anterior or posterior optical surface in a central circular area of the IOL optic caused the opacification. The calcifications lead to deterioration of the modulation transfer function (MTF) across all spatial frequencies.

CONCLUSION

PPV with instillation of gas into a pseudophakic eye with an acrylic hydrophilic lens seems to increase the risk for secondary calcification irrespective of the manufacturer. In these cases, IOL exchange is the only treatment option available. Since IOL exchange is associated with a high intraoperative complication rate, our results suggest to consider the risk of IOL calcification when implanting hydrophilic acrylic IOLs.

Intraocular Lens Calcifications After (Triple-) Descemet Membrane Endothelial Keratoplasty

PURPOSE

To identify incidence of and risk factors for calcifications of intraocular lenses (IOLs) after Descemet membrane endothelial keratoplasty (DMEK).

DESIGN

Retrospective cohort study.

METHODS

Retrospective review of charts and slit-lamp images of 564 consecutive patients from the prospective Cologne DMEK database who underwent DMEK in pseudophakic eyes or DMEK in combination with cataract surgery (triple-DMEK) between September 3, 2013 and October 30, 2015 at the Department of Ophthalmology, University of Cologne.

RESULTS

IOL calcifications after (triple-)DMEK occurred in 14 patients (2.5%). Visual acuities in affected and unaffected eyes were 0.33 ± 0.24 logMAR and 0.16 ± 0.01 logMAR after 3 months (P < .001) as well as 0.28 ± 0.16 logMAR and 0.13 ± 0.08 logMAR (P < .001) after 6 months, respectively. The proportions of triple-DMEK vs DMEK, the use of SF6 gas vs room air for anterior chamber tamponade, and the presence of hydrophilic vs hydrophobic acrylic IOLs were comparable in affected and unaffected eyes. Patients with IOL calcifications had higher rebubbling rates than patients without. Larger pupil diameters at the time of surgery showed a tendency to slightly larger areas of IOL calcifications.

CONCLUSIONS

IOL calcifications after anterior chamber gas tamponade in DMEK lead to visual impairment and are associated with the number of rebubblings after DMEK. IOL calcifications also occur in hydrophobic acrylic IOLs.

Trends in corneal transplant surgery in Ireland: indications and outcomes of corneal transplant surgery and intraocular lens opacification following Descemet's stripping automated endothelial keratoplasty

PURPOSE

To evaluate the indications for corneal transplantation, the procedures carried out, and the postoperative outcomes and to compare these with previous Irish corneal transplant studies.

METHODS

A retrospective review of the case notes of all patients who underwent corneal transplantation under the care of a single surgeon, from 2008 to 2015, was performed. The risk factors for postoperative complications including transplant failure were examined.

RESULTS

During the period studied, 42 corneal transplant surgeries were carried out on 40 eyes of 38 patients, 24 of whom were male (63%), median age at surgery was 62 years (range 23-96 years). The most common indication for transplantation was pseudophakic corneal decompensation associated with Fuch's endothelial dystrophy (FED) (n = 13). Seventeen penetrating keratoplasties, 23 lamellar keratoplasties, and two amniotic membrane transplant procedures were carried out. Transplant failure resulting in corneal oedema or repeat corneal transplant surgery (n = 4, 10%), was associated with previous transplant failure in the eye; odds ratio (OR) = 1.58 (p = 0.05), and with comorbid FED, OR = 1.50 (p = 0.02). Intraocular lens opacification occurred in one lens following DSAEK, giving an incidence rate of 7%.

CONCLUSIONS

Pseudophakic corneal decompensation is the commonest indication for corneal transplant surgery, with lamellar keratoplasty the most frequent approach in our cohort, reflecting developments observed in corneal transplant surgery elsewhere. Prior corneal transplant failure and Fuch's dystrophy remain important risk factors for failure. The risk of intraocular lens opacification and its potential effects on vision should be elaborated prior to endothelial keratoplasty.

Intraocular lens opacification after Descemet's stripping automated endothelial keratoplasty

Compared with conventional penetrating keratoplasty, Descemet's stripping automated endothelial keratoplasty (DSAEK) more effectively maintain global integrity and rapid vision rehabilitation with less ocular surface disorders in patients with endothelial dysfunction. Here, we report a case of a 76-year-old woman who experienced opacification of a hydrophilic intraocular lens (IOL) approximately 10 months after DSAEK. The patient with no history of systemic disease developed pseudophakic bullous keratopathy in the right eye 2 years after undergoing cataract surgery. The best-corrected visual acuity (BCVA) of the right eye was Snellen 0.01 when presented to our hospital. DSAEK was arranged and performed smoothly. However, the graft detached over the upper part of the cornea on postoperative day 1. Thus, rebubbling was performed immediately. After the procedure, the graft was well attached, and the cornea became clear gradually. The BCVA returned to Snellen 0.6. However, progressive opacification over the anterior surface of the IOL was observed 10 months postoperatively. Vision deteriorated to 0.5 with various refractive errors during 2-year follow-up. IOL exchange may be considered if the vision is getting worse. IOL opacification may result from a direct contact between the IOL surface and exogenous air, particularly in a hydrophilic IOL, and can be a rare but significant complication after DSAEK. Clinicians planning to perform DSAEK should consider the composition of the IOL, the amount of intracameral air, duration of air filling, and high intraocular pressure.

Calcification of Hydrophilic Acrylic Intraocular Lenses With a Hydrophobic Surface: Laboratory Analysis of 6 Cases

PURPOSE

To investigate the nature and characteristic features of deposits causing opacification of intraocular lenses (IOLs) based on the examination of clinical findings using scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX) analysis.

DESIGN

Retrospective, observational case series.

METHODS

This is a multicenter study of 6 hydrophilic acrylic IOLs (Lentis LS-502-1; Oculentis GmbH, Berlin, Germany) with a hydrophobic surface that were explanted from 5 patients because of opacification. Three patients had an uncomplicated phacoemulsification. One patient underwent combined phacoemulsification and pars plana vitrectomy for retinal detachment and later silicone oil endotamponade owing to redetachment. The last patient had a pars plana vitrectomy and silicone oil instillation combined with phacoemulsification for tractive retinal detachment and diabetic retinopathy. The explanted lenses were submitted to our laboratory and were examined by SEM and EDX in order to identify the morphologic features and the composition of the deposits.

RESULTS

SEM and EDX analyses confirmed the presence of calcific deposits in the interior of the opacified hydrophilic IOLs, with a pattern showing the formation of lumps on the surface. The lumps were due to subsurface formation of calcium phosphate crystalline deposits. The crystallite clusters seemed to diffuse from the IOL interior to the surface.

CONCLUSIONS

We demonstrated the calcification pattern of the hydrophilic IOL (Lentis LS-502-1) with a hydrophobic surface. Although hydrophilic acrylic lenses have a hydrophobic surface, the development of calcification is a possible threat initiating from the hydrophilic subsurface of the IOLs.

[Triple Descemet membrane endothelial keratoplasty. Indications, variations and results]

When Descemet membrane endothelial keratoplasty (DMEK) is indicated in patients with phakic eyes, a combination with phacoemulsification and intraocular lens implantation in one sitting should be considered as a triple DMEK. The best possible preoperative deswelling of the cornea should be strived for in order to allow sufficient viewing conditions for the individual stages of cataract surgery. Furthermore, technical details, e.g. regulation of pupillary width also must be considered. The power of the intraocular lens has to be adjusted in order to compensate for the shift of refraction towards hyperopic values induced by DMEK surgery. A rapid and clear improvement in visual acuity can normally be achieved after a triple DMEK. There seem to be no disadvantages compared with a two-stage procedure for DMEK and cataract surgery.