Bilateral trifocal IOL implantation in a pediatric case of cataract following steroid-therapy for acute lymphoblastic leukemia

Higher phosphate concentrations as in aqueous humor of diabetic patients increase intraocular lens calcification

BACKGROUND

Clinical evidence suggests an association between phosphate concentrations in aqueous humor and the risk of intraocular lens (IOL) calcification. To test this hypothesis the influence of different phosphate concentrations on IOL calcification was evaluated in an in vitro electrophoresis model.

METHODS

20 IOLs of two hydrophilic IOL models (CT Spheris 204, Zeiss; Lentis L-313, Oculentis) and one hydrophobic control IOL model (Clareon CNA0T0, Alcon) were exposed to physiologic and elevated phosphate concentrations, similar to diabetic aqueous humor. IOL calcification was analyzed by alizarin red staining, von Kossa staining, scanning electron microscopy, energy dispersive x-ray spectroscopy and transmission electron microscopy with electron diffraction.

RESULTS

Higher phosphate concentrations were associated with IOL calcification. Analyses of IOL surfaces and cross-sections documented calcification in no CT Spheris and 4 Lentis IOLs following exposure to 10 mM Na2HPO4, compared with 7 and 11 positive analyses following exposure to 14 mM Na2HPO4, respectively. Furthermore, a clear association between IOL calcification and the duration of electrophoresis was demonstrated, confirming increased phosphate concentrations and duration of exposure as risk factors of IOL calcification.

CONCLUSIONS

Findings suggest that higher phosphate concentrations in aqueous humor, as seen in diabetic patients, contribute to an increased IOL calcification risk, potentially explaining clinical observations showing an increased risk of IOL calcification in patients with diabetes.

Reversible Multifocality Achieved Through Polypseudophakia

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

Premium intraocular lenses in children

Multifocal and toric intraocular lenses (IOLs) or the so-called premium IOLs are currently widely used in adult patients as a one-step refractive solution following cataract surgery. However, the decision to implant a premium IOL in a pediatric patient involves multiple factors affecting the child's visual development and is associated with several dilemmas and surgical challenges. The purpose of this review is to summarize these factors and analyse the influence of each of them on the visual outcomes following premium IOL implantation. A review of literature was conducted using the relevant keywords from various databases until 31^st January 2022. All pertinent studies with multifocal or toric IOL implantation in children were reviewed, and relevant articles were studied in detail for age, IOL power calculation, visual outcomes (refractive outcomes, contrast sensitivity and stereopsis) and complications such as dysphotic phenomena and others. A total of 17 relevant studies (10 case series/interventional studies and 7 case reports) on the subject were included. All studies showed a favourable refractive outcome; however, the data available was significantly less. Studies with earlier models of multifocal IOLs showed a higher incidence of IOL decentration and posterior capsule opacification; however, more recent studies with newer IOL models showed much better safety profiles. Toric IOLs showed promising results in all the studies evaluated. Premium IOLs have shown promising results in the pediatric age group. However, their long-term outcomes specifically concerning refractive shift, capsular contraction and role in the management of amblyopia needs to be explored further.

Clinical outcomes in patients after duet procedure for reversible trifocality using a supplementary trifocal IOL

PURPOSE

We report the clinical outcomes of patients who had primary lens implantation in the capsular bag and subsequently a supplementary trifocal lens implanted in the ciliary sulcus (duet procedure) to create reversible trifocality.

DESIGN

Retrospective interventional case series.

METHODS

Twenty-five patients were included in this single center clinical study, who had undergone either refractive lens exchange for presbyopia correction or cataract surgery. All had lens removal by phacoemulsification and duet procedure to achieve reversible trifocality. Preoperatively and three months postoperatively, uncorrected (UDVA) and corrected distance visual acuity (CDVA) were assessed, as well as uncorrected (UNVA), distance corrected (DCNVA) and corrected near visual acuity (CNVA). At the postoperative examination, uncorrected (UIVA), distance corrected (DCIVA) and corrected intermediate visual acuity (CIVA), defocus curve testing and dysphotopsia evaluation were also performed.

RESULTS

Monocular UDVA and CDVA improved from 0.71 ± 0.43 logMAR and 0.12 ± 0.16 logMAR preoperatively to 0.04 ± 0.10 logMAR and -0.01 ± 0.09 logMAR postoperatively. Monocular UNVA and DCNVA were both 0.06 ± 0.08 logMAR and UIVA and DCIVA 0.00 ± 0.10 logMAR and -0.02 ± 0.10 logMAR postoperatively. Monocular defocus curve testing revealed a visual acuity of 0.2 logMAR or better from +0.75 to -3.5 diopters.

CONCLUSIONS

Duet procedure using a trifocal supplementary IOL provided excellent results for far, near and intermediate distance, comparable to those reported for capsular bag fixated trifocal IOLs. The duet procedure offers the advantage of an exit-strategy in cases with a future loss of function or side effects associated with the optics.

[Opacification of Intraocular Lenses]

The spectrum of complications in the use of intraocular lenses (IOL) is different today from at the time of their introduction. Opacities in the IOL material are increasingly described in the literature as a reason for IOL explantation. This paper provides an overview of the different forms of IOL material opacities. Currently relevant forms of IOL material opacities and their effects on optical quality are summarized. The main reason for opacification in hydrophilic IOLs is calcification, whereas in hydrophobic IOLs it is mainly the formation of so-called glistenings that is reported. Most material opacities affect various optical parameters and lead to increased intraocular straylight. In case of a disturbing material opacification, the only therapeutic option is to replace the opacified IOL.

Eintrübung von Intraokularlinsen

Das Spektrum an Komplikationen und die Explantationsgründe bei der Verwendung von Intraokularlinsen (IOL) haben sich durch die Weiterentwicklung der Kataraktchirurgie verändert. Eintrübungen des Materials beeinflussen dabei unterschiedlich stark die optische Qualität. Im Fall einer störenden Eintrübung des Materials ist auch heute noch – trotz aller Fortschritte auf dem Gebiet der IOL-Materialien – ein Austausch der IOL die einzige Behandlungsoption.

A review of late intraocular lens opacifications

PURPOSE OF REVIEW

Phacoemulsification cataract surgery is one of the most commonly performed surgical procedure worldwide. In the majority of cases, intraocular lenses (IOLs) are implanted. Due to the increasing life expectancy and the fact that cataract surgery is performed in earlier stages, the anticipated IOL duration in the eye has increased over the last decades. The aim of this study was to review the types and describe the characteristics of late intraocular lens opacifications.

RECENT FINDINGS

Calcification was the most commonly reported type of opacification in hydrophilic IOLs; it usually negatively impacted the visual function and required IOL explantation. Glistening manifested in hydrophobic acrylic lenses and was frequent in some IOL models. In most cases glistening and subsurface nanoglistenigs do not lead to a decline in visual acuity or require IOL exchange. Current studies indicate that fluid-related phenomena may induce straylight, leading to a decrease of comfort and quality of vision.

SUMMARY

Several reports on late IOL opacifications have been published in recent years. In some cases, particularly in glistening, the development of the opacifications might be related to IOL aging. The influence of the fluid-related microvacuoles on the quality of vision requires further research.

[Duet procedure to achieve reversible trifocality]

Funktionelle Ergebnisse und das Auftreten von Nebenwirkungen (insbesondere photischer Phänomene) können beim Einsatz multifokaler Intraokularlinsen (IOL) schwer vorhergesagt werden. Des Weiteren können Patienten im Laufe des Lebens Erkrankungen entwickeln, bei denen eine multifokale Optik von Nachteil sein kann. In diesen Fällen ist ein Austausch der IOL die einzige Therapieoption. Die Implantation einer monofokalen oder monofokal-torischen IOL in den Kapselsack und einer additiven trifokalen IOL in den Sulcus ciliaris in einer als Duett-Verfahren bezeichneten Operation ermöglicht Trifokalität, die bei Bedarf vergleichsweise einfach wieder rückgängig gemacht werden kann.

[Opacification of intraocular lenses: laboratory and clinical findings]

Hintergrund

Das Spektrum der Komplikationen beim Einsatz von Intraokularlinsen (IOL) ist heute ein anderes als zur Zeit ihrer Einführung. Trübungen im IOL-Material werden vermehrt als Explantationsgrund in der Literatur beschrieben.

Ziel der Arbeit

Diese Arbeit soll einen Überblick über die verschiedenen Formen von IOL-Materialeintrübungen geben.

Material und Methoden

Die heute relevanten Formen von IOL-Materialeintrübungen und deren Auswirkungen auf die optische Abbildungsqualität wurden zusammengestellt.

Ergebnisse und Diskussion

Als Grund für eine Eintrübung steht bei hydrophilen IOL die Kalzifikation im Vordergrund, während bei hydrophoben IOL v. a. über die Entstehung sog. „Glistenings“ berichtet wird. Die meisten Materialeintrübungen beeinflussen verschiedene optische Parameter und führen zu einem erhöhten intraokularen Streulicht. Im Falle einer störenden Materialeintrübung besteht die einzige Therapieoption in einem Austausch der eingetrübten IOL.

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

Purpose

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

Observations

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

Conclusions

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

Trifocal toric intra-ocular lens implantation in pediatric traumatic cataract

Purpose

To present the case of a 6-year-old child who presented with a traumatic cataract and was treated with trifocal toric intra-ocular lens implantation.

Observations

The child's uncorrected distance visual acuity improved from +0.7 logMAR preoperatively to 0.00 logMAR after cataract surgery, with spectacle independence and no reported side effects

Conclusions and importance

In carefully selected pediatric patients with traumatic cataracts, trifocal toric intra-ocular lenses may offer some benefit over standard monofocal lenses