Irreversible silicone oil adhesion to silicone intraocular lenses. A clinicopathologic analysis

Quantification of Straylight Induced by Silicone Oil Adherent to Intraocular Lenses of Different Materials

PURPOSE

A complication of using silicone oil as an intraocular endotamponade is its adhesion to intraocular lenses (IOLs). Forward light scattering is a measure to quantify the optical disturbance caused by adherent oil droplets. We tested the straylight caused by silicone oil adhesion to different IOLs and examined whether an approved cleaning solution, F4H5, reverses the induced straylight.

DESIGN

An experimental study.

METHODS

Two hydrophobic acrylic IOL models and 1 hydrophilic model with a hydrophobic surface (n = 8 per model: 24 lenses) had straylight measured before contact with silicone oils, providing a baseline for subsequent testing: 12 lenses with lighter-than-water silicone oil (Siluron 2000) and 12 with heavier-than-water oil (Densiron 68). The final measurement was performed after cleansing with F4H5 when we used scanning electron and light microscopy to detect surface changes.

RESULTS

Straylight was majorly increased in IOLs with adherent silicone oil (baseline vs adherent oil median 3.1 [2.1, 3.9] and 39.7 [22.7, 87.8] deg2/sr, respectively; P < .001). No difference was seen between heavier- and lighter-than-water silicone oils. Between IOL types, induced straylight varied significantly, with 1 hydrophobic model reaching the highest average straylight. F4H5 significantly reduced straylight values in all IOL types (median 9.4 [5.4, 13.8] deg2/sr). The microscopy revealed surface changes on the IOLs even after cleaning.

CONCLUSIONS

Silicone oil adhesion to IOLs can induce amounts of straylight known to cause severe optical disturbance. F4H5 cleansing solution reversed straylight values to only slightly increased values. We found no difference in straylight formation between the lighter- and heavier-than-water silicone oils.

Modified intrascleral haptic fixation of the light adjustable lens in a case of spontaneous adult-onset bilateral lens subluxation

Purpose

To describe the application of the light adjustable lens (LAL) using an intrascleral haptic fixation (ISHF) technique for the correction of aphakia and post-operative refractive error.

Observation

The LAL was placed using a modified trocar-based ISHF technique for visual rehabilitation following removal of bilateral cataracts in a patient with ectopia lentis. She ultimately obtained an excellent refractive outcome after adjustment with micro-monovision.

Conclusions and Importance

Secondary intraocular lens placement has a much higher risk of residual ametropia than traditional in-the-bag lens placement. The ISHF technique with the LAL presents a solution for eliminating postoperative refractive error in patients requiring scleral-fixated lenses.

Silicone Oil Adhesion to Hydrophobic Acrylic Intraocular Lenses: A Comparative Laboratory Study of a New versus an Established Hydrophobic Acrylic Intraocular Lens Material

Background

In vitro assessment of silicone oil adhesion to a new hydrophobic acrylic intraocular lens (IOL) material, the Clareon model CNA0T0, compared with the established AcrySof model SN60WF was carried out.

Methods

Silicone oil adhesion was assessed for two types of IOLs, Clareon CNA0T0 (n = 10) and AcrySof SN60WF (n = 10). Lenses were immersed in an aqueous sodium chloride solution for 12 hours and then incubated at room temperature in silicone oil for 12 hours. The lenses were washed with distilled water and photographed at 25x magnification using a microscope. The percent coverage was calculated by dividing the area of oil coverage by the total surface area of the lens.

Results

Silicone oil adhesion to the surface of the CNA0T0 lens ranged from 4% to 22%, with a mean ± SD coverage of 8% ± 4%. Silicone oil adhesion to the surface of the SN60WF lens ranged from 1% to 17%, with a mean coverage of 9% ± 4%. The silicone oil adhesion of CNA0T0 was equivalent to that of SN60WF (P > 0.05).

Conclusions

The new Clareon model CNA0T0 IOL has silicone oil adhesion and interaction that are equivalent to the established AcrySof IOL.

Persistent Air Bubble Sequestered at the Silicone Oil–Silicone Intraocular Lens Interface as a Cause of Reversible Visual Distortion

Purpose:

To report a novel cause of post-operative reversible visual distortion due to a persistent air bubble sequestered at the intraocular lens (IOL)–silicone oil interface.

Methods:

Two cases of persistent, sequestered air at the IOL-silicone oil interface were identified and reviewed. Relevant clinical information, images and surgical videos were analyzed and described.

Results:

Resolution of the visual distortion was achieved in both cases after silicone oil removal.

Conclusions:

Silicone oil adhesion to the posterior surface of silicone IOLs is a known cause of visual degradation. The IOL-silicone oil interface can sequester air that persists and causes visual distortion until the oil is removed. We report the first cases, to our knowledge, of reversible visual distortion due to sequestered air at the IOL-silicone oil interface.

Cataract Following Pars Plana Vitrectomy: A Review

Introduction: The indications for pars plana vitrectomy (PPV) have increased over the years. The vitreous is no longer considered an inert ocular structure and it is well known that its removal has anatomical and physiological consequences. The vitreous is no longer considered an inert ocular structure. The vitreous plays a key role as an intraocular physiologic oxygen regulator. In order to maintain its transparency, the crystalline lens needs protection from an excessive oxygen exposure. PPV leads to progression of nuclear sclerosis in most eyes.Methods: A systematic review of the literature was conducted using Embase and Medline databases. Articles studying the physiology, pathogenesis and surgical treatment of cataract after PPV were included in this review.Results: The pathogenesis of cataract formation after PPV remains unclear. Predisposing factors include advanced patient age, preexisting nuclear sclerosis, light toxicity, intraoperative oxidation of lens proteins, use of silicone oil or intravitreal gas, mechanical trauma and the duration of exposure to an irrigating solution.Conclusion: Cataract surgery in vitrectomized eyes presents with more technical difficulties, is more challenging and often has a higher risk of intraoperative and postoperative complications than in non vitrectomized eyes. There is no standardized technique or management in these cases; therefore, it requires more precautions during surgery.

[Proliferative vitreoretinopathy (PVR) surgery: Scar Wars : Five steps to successful treatment of PVR detachment]

BACKGROUND

After initially successful surgery of retinal detachment, proliferative vitreoretinopathy (PVR) is the most common cause of renewed retinal detachment. With an incidence of 5-20% it represents a frequent surgical challenge based on a pronounced epiretinal, subretinal and intraretinal scar formation.

MATERIAL AND METHODS

The five most important steps leading to a successful repair of a PVR retinal detachment are described.

RESULTS

1. The basic prerequisite is the complete removal of the vitreous body in order to remove the substrate for proliferation of pathological cells. 2. Furthermore, the complete removal of all tractional PVR membranes is necessary. Subretinal PVR membranes that show no traction can be left in place. 3. The professional care of the macular is still important. As approximately 12% of all patients who undergo surgery for retinal detachment develop an epiretinal gliosis/macular pucker, peeling of the internal limiting membrane (ILM) is obligatory in cases of PVR. 4. Particularly in PVR detachment the mentioned surgical procedure is facilitated by the selection of suitable modern instruments, including wide-angle optics, such as the binocular indirect ophthalmomicroscope (BIOM), chandelier lights, perfluorocarbons (PFCL) and silicone oil. 5. Last but not least, the credo as much as necessary, as little as possible is of essential importance, as PVR eyes have usually been previously operated on and any further surgical intervention leads to subsequent inflammation and a persisting stimulation of the PVR reaction and further damage.

CONCLUSION

Following a few decisive rules and tips is a prerequisite for a successful reattachment in cases of PVR retinal detachment.

Advances in the Study of Lens Refilling

The ultimate goal of cataract surgery is to restore the accommodation while restoring distance visual acuity. Different kinds of accommodative intraocular lens (IOLs) and surgical techniques have been suggested to apply during the surgery, but they showed poor postoperative accommodation. It is possible to achieve this goal by refilling the lens with an injectable polymer. We present a summary of the existing materials, methods, results, and some obstacles in clinical application that remain of lens refilling for restoration of accommodation. Two main problems have restricted the clinical application of this technique. One was the formation of postoperative secondary capsule opacification and the other was the different accommodative power after surgery.

Intraocular Lens Complications: Decentration, Uveitis-Glaucoma-Hyphema Syndrome, Opacification, and Refractive Surprises

As cataract surgery has evolved, intraocular lens (IOL) complications are rare. The purpose of this review was to report the incidence, diagnosis, and management of IOL decentrations, uveitis-glaucoma-hyphema (UGH) syndrome, IOL opacifications, and refractive surprises. Literature review was performed by searching PubMed, MEDLINE, EMBASE, and the Cochrane Controlled Trial Database and the reference lists of original studies as well as reviews. Intraocular lens decentrations and dislocations can appear at any time, particularly in patients with predisposing factors such as pseudoexfoliation, prior vitreoretinal surgery, or trauma. Recognizing when they require surgical intervention for UGH or to improve visual function is critical in limiting long-term sequela. Intraocular lens opacifications such as glistenings rarely require intervention, but others, such as subsurface nanoglistenings, calcifications, or discolorations, may require IOL exchange. Finally, despite our best efforts to enhance measurements and IOL calculations, refractive surprises still occur. Intraocular lens complications are uncommon with modern cataract surgery. A number of these complications require proper identification and care to optimize patient outcomes.

Adherence of Intravitreal Silicone Oil Bubbles to a Silicone Intraocular Lens

The authors present a case of diffuse silicone oil deposits from intravitreal anti-vascular endothelial growth factor injections adhering to the posterior capsule of a silicone intraocular lens. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:307.].

Clinical and material degradations of intraocular lenses: A review

PURPOSE

To review the published scientific literature concerning clinical and material degradations of intraocular lenses after implantation in cataract surgery.

METHODS

A search was undertaken using the following databases: CENTRAL (including Cochrane Eyes and Vision Trials Register; The Cochrane Library: Issue 2 of 12 February 2019), Ovid MEDLINE (R) without Revisions (1996 to February week 2, 2019), Ovid MEDLINE (R) (1946 to February week 2, 2019), Ovid MEDLINE (R) Daily Update 19 February 2019, MEDLINE and MEDLINE non-indexed items, Embase (1980-2019, week 7), Embase (1974-2019, 19 February), Ovid MEDLINE (R) and Epub Ahead of Print, in-Process & Other Non-Indexed Citations and Daily (1946 to 19 February 2019), Web of Science (all years), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and the WHO International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Only published articles in English were selected. Search terms/keywords included 'IOL' or 'intraocular lens', combined with 'opacification', degradation, glistenings, nanoglistenings, whitening, transmittance, light scatter, discolouration/discoloration, performance, quality, material, biocompatibility, calcification, explantation and ultraviolet/UV radiation. Relevant in-article references not returned in our searches were also considered.

RESULTS

After review of the available articles, the authors included 122 publications in this review, based on the quality of their methodology and their originality. The studies included in this review were randomized controlled trials, cohort studies, case-controlled studies, case series, case reports, laboratory studies and review papers. Differing material degradations of intraocular lenses have been described and their associated pathophysiology studied. Reported anomalies include photochemical alterations, water vacuoles, internal and surface calcific deposits, surface coatings and discolouration. The nature of such changes has been shown to depend on the type of intraocular lenses material used and/or manufacturing processes and storage conditions employed. Changes in the intraocular lens can also be influenced by surgical technique, coexisting ocular pathologies and topical and systemic medications. The clinical significance of these degradations is variable, with some resulting in significant visual disturbance and the need for intraocular lens explantation and others producing only minimal visual impairments. Failure to recognize the precise nature of the problem may lead to unnecessary laser capsulotomy procedures.

CONCLUSION

Clinical degradations of intraocular lenses are uncommon but have been reported following the implantation of intraocular lenses made of differing biomaterials. Their correct identification and thorough investigation to determine the underlying cause is necessary for optimal patient management and the prevention of such problems. Choosing a lens made of a particular material may be important in patients with certain ocular conditions.

Effects of Perfluorobutylpentane (F4H5) on Corneal Endothelial Cells

Purpose: To evaluate the effects of perfluorobutylpentane (F4H5) on corneal endothelial cell density (ECD) and morphology using a porcine corneal endothelial organ culture model. Materials and methods: "Split corneal buttons" were cultivated for 15 days (d) after incubation in F4H5 (15, 30, 60, and 120 min) or BSS (controls). ECD was assessed manually on d1, d8, and d15. After histological staining (trypan blue, alizarin red S) on d15 morphological changes (reformation figures, rosette formations, and alizarin red cells) were evaluated. Results: ECD was significantly reduced after incubation in F4H5 for 120 min (median ± 25%/75%-quartile; 3281 ± 43/222 cells/mm²; p = 0.046) on d15 compared to controls (3658 ± 129/296 cells/mm²), but not after shorter incubation times (15, 30, and 60 min). Morphological assessment supports these findings as reformation figures (F4H5 120 min: 10.5 ± 9.3/13.9/mm² vs. controls: 5.2 ± 2.8/7.2/mm²; p = 0.010), rosette formations (F4H5 120 min 25.566 ± 17.044/36.219/mm² vs. controls: 8.333 ± 0.000/15.667/mm²; p = 0.002), and alizarin red cells (F4H5 120 min: 38.350 ± 29.827/51.333/mm² vs. controls: 20.833 ± 10.417/25.000/mm²; p = 0.049) were significantly more prevalent after incubation in F4H5 for 120 min compared to controls. Also, F4H5 60 min showed significantly more rosette formations (25.452 ± 16.968/36.057/mm²; p = 0.006) and alizarin red cells (46.662 ± 42.420/50.903/mm²; p = 0.007), but not reformation figures (7.0 ± 2.2/1.6 %; p = 0.953). Conclusion: Short exposure (≤30 min) of porcine corneal endothelial cells to F4H5 does not have significant effects on ECD or morphological characteristics. Longer exposure times (≥60-120 min) may cause ECD decline and/or induce morphological changes.

Removal of silicone oil droplets adhering to the posterior surface of an intraocular lens (IOL)

Purpose

We report a rare case of silicone oil droplets adhering to the posterior surface of an intraocular lens (IOL) after removal of silicone oil for a patient with retinal reattachment, who had a history of pseudophakic rhegmatogenous retinal detachment.

Case report

A 45-year-old male with a history of cataract surgeries of both eyes developed pseudophakic retinal detachment in his left eye. He received surgeries of scleral buckle and standard 3-port pars plana vitrectomy with silicon oil tamponade. With retinal attachment for 7 months, he underwent removal of silicone oil in the left eye. However, a big silicone oil droplet was found on the posterior surface of the IOL with complaints of distorted micropsia and poor vision, a month later. Pars plana vitrectomy using a 20-gauge vitreous cutter, which was supposed to have a higher cleaning capability compared with a smaller size device, was performed to aspirate the main part of the big oil droplet. The residual dispersed smaller droplets at the center of the visual axis were swept peripherally using a 27-gauge bending tip cannula. Fortunately, the patient regained his vision of 20/20 without distortion and micropsia in his left eye.

Conclusion

This was a rare case where silicone oil droplets were found adhering to the posterior surface of an IOL after removing silicone oil a month later. We used a 20-gauge vitrectomy system to remove large oil droplets and swept smaller ones off the visual axis to improve the vision and visual quality.

Spectroscopic studies of the silicone oil impact on the ophthalmic hydrogel based materials conducted in time dependent mode

Silicone oil is the one of the artificial materials used in vitreoretinal surgery for retinal detachment treatment. Since the silicone oil is sometimes applied along with intraocular lens (IOL) implantation the direct influence of silicone oil on the artificial implant should be taken into account. Presented study was performed in order to determine the time-dependent impact of silicone oil on hydrogel based ophthalmic materials. Two kinds of IOLs based on hydroxyethyl 2-methacrylate (HEMA) hydrogel material were immersed in silicone oil based on linear poly(dimethylsiloxane) (PDMS). Incubation in oil medium was performed in 37°C for 1, 3 and 6months. After appropriate period of the incubation samples were examined by means of FTIR-ATR method as the technique of surface study as well as Positron Annihilation Lifetime Spectroscopy (PALS) as the method of internal structure investigation. Results obtained during the study revealed that silicone oil is not capable to penetrate the internal structure of investigated materials and its impact has come down to interaction with the samples surfaces only.

Phacoemulsification in Previously Vitrectomized Patients: An Analysis of the Surgical Results in 100 Eyes as well as the Factors Contributing to the Cataract Formation

Purpose

To evaluate the safety and effectiveness of phacoemulsification with clear corneal incision in previously vitrectomized patients as well as factors affecting the development time and type of cataract occurring after pars plana vitrectomy (PPV).

Methods

The authors conducted a prospective study of 100 consecutive eyes of patients who developed a cataract after PPV. Three groups were established based on the underlying vitreoretinal pathology. The main outcome measurements were intraoperative and postoperative complications and changes in best-corrected visual acuity (BCVA).

Results

The median interval between PPV and phacoemulsification was 11.5 months. Patients with proliferative diabetic retinopathy required phacoemulsification earlier (p=0.018). Posterior subcapsular cataracts developed more frequently in patients <50 years (73.7%, p=0.000) and affected those who underwent vitrectomy primarily for complicated retinal detachment (48.8%, p=0.046). Intraoperative complications included posterior capsular tears (4%), luxated nucleus into vitreous (2%), and zonular dialysis (5%). Postoperative complications were vitreous hemorrhage (6%), retinalredetachment (4%), pupillary synechiae (6%), ocular hypertension (4%), and Seidel phenomenon (3%). Posterior Nd:YAG laser capsulotomy was required in 44% of eyes. BCVA was improved in 85% of cases at the end of follow-up (median, 15.5 months). Twenty-one patients with one functioning eye (61.9%) demonstrated visual improvement compared with 79 patients with bilateral vision (91.1%; p=0.003).

Conclusions

The technique allows stable improvement in BCVA through long follow-ups. It is more risky than in nonvitrectomized eyes. The visual results after phacoemulsification in vitrectomized eyes seem to be limited by retinal comorbidity and surgical complications.

Surface Modification of Intraocular Lenses

Objective:

This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs).

Data Sources:

All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect.

Study Selection:

The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded.

Results:

Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO₂, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments.

Conclusion:

The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs.

Biocompatibility of a Synthetic Biopolymer for the Treatment of Rhegmatogenous Retinal Detachment

OBJECTIVE

The aim of this study is to evaluate the retinal safety and toxicity of a novel synthetic biopolymer to be used as a patch to treat rhegmatogenous retinal detachment.

METHODS

Thirty one adult wild type albino mice were divided in 2 groups. In Group A (n=9) 0.2 μl balanced salt solution (BSS) and in Group B (n=22), 0.2 μl biopolymer was injected in the subretinal space. Trans-scleral subretinal injection was performed in one eye and the fellow eye was used as control. In both groups, in vivo color fundus photography, electroretinogram (ERG), spectral domain optical coherence tomography (SD-OCT) were performed before injection and at days 7 and 14 post-intervention. Histological analysis was performed following euthanization at days 1, 7 and 21 post-injection.

RESULTS

The biopolymer was visualized in the subretinal space in vivo by SD-OCT and post-life by histology up to 1 week after the injection. There were no significant differences in ERG parameters between the two groups at 1 and 2 weeks post-injection. Minimal inflammatory response and loss of photoreceptor cells was only observed in the immediate proximity of the site of scleral perforation, which was similar in both groups. Overall integrity of the outer, inner retina and retinal pigment epithelial (RPE) layers was unaffected by the presence of the biopolymer in the subretinal space.

CONCLUSIONS

Functional and histological evaluation suggests that the synthetic biopolymer is non-inflammatory and non-toxic to the eye. It may represent a safe therapeutic agent in the future, for the treatment of rhegmatogenous retinal detachment.

Removal of Silicone Oil From Intraocular Lens Using Novel Surgical Materials

PURPOSE

To design, fabricate, and evaluate novel materials to remove silicone oil (SiO) droplets from intraocular lenses (IOL) during vitreoretinal surgery.

METHODS

Three different designs were fabricated using soft lithography of polydimethylsiloxane (PDMS), three-dimensional (3D) inverse PDMS fabrication using water dissolvable particles, and atomic layer deposition (ALD) of alumina (Al₂O₃) on surgical cellulose fibers. Laboratory tests included static and dynamic contact angle (CA) measurements with water and SiO, nondestructive x-ray microcomputer tomography (micro-CT), and microscopy. SiO removal was performed in vitro and ex vivo using implantable IOLs and explanted porcine eyes.

RESULTS

All designs exhibited enhanced hydrophobicity and oleophilicity. Static CA measurements with water ranged from 131° to 160° and with SiO CA approximately 0° in 120 seconds following exposure. Nondestructive x-ray analysis of the 3D PDMS showed presence of interconnected polydispersed porosity of 100 to 300 μm in diameter. SiO removal from IOLs was achieved in vitro and ex vivo using standard 20-G vitrectomy instrumentation.

CONCLUSION

Removal of SiO from IOLs can be achieved using materials with lower surface energy than that of the IOLs. This can be achieved using appropriate surface chemistry and surface topography. Three designs, with enhanced hydrophobic properties, were fabricated and tested in vitro and ex vivo. All materials remove SiO within an aqueous environment. Preliminary ex vivo results were very promising, opening new possibilities for SiO removal in vitreoretinal surgeries.

TRANSLATIONAL RELEVANCE

This is the first report of an instrument that can lead to successful removal of SiO from the surface of IOL. In addition to the use of this instrument/material in medicine it can also be used in the industry, for example, retrieval of oil spills from bodies of water.

[Complications of silicone oil tamponade]

Silicone oil tamponade is used for the management of complicated retinal detachment. Patients should be closely monitored as many complications may occur with intraocular silicone oil. Short-term complications include temporarily increased intraocular pressure and anterior segment inflammation. Long-term complications include cataract, emulsification, ocular hyper- or hypotension, keratopathy and retinal redetachment associated with proliferative vitreoretinopathy.

[Pseudophakic retinal detachment: how to manage?]

INTRODUCTION

Retinal detachment, a common complication of cataract surgery, requires urgent surgical treatment. The external approach combining retinopexy with scleral buckling remains the gold standard in the surgical management of pseudophakic retinal detachment (RD) without marked proliferative vitreoretinopathy (PVR), although intraocular surgery is currently preferred by most of the authors. The purpose of this study is to compare the anatomical and functional results obtained with both techniques.

PATIENTS AND METHODS

This study compares the results of two techniques for treating pseudophakic retinal detachment: external surgery (group I), and vitrectomy with internal tamponade (group II). Ab-externo surgery was performed in 24 patients (24 eyes), while 22 patients (22 eyes) underwent primary vitrectomy. In order to make both groups comparable, we excluded recurrences of RD, vitreous hemorrhage and other media opacities, giant tears and initial grade C PVR. Minimum follow-up was 12 months. Postoperative variables analyzed and compared were the rate of initial and final anatomical success, final visual acuity, and causes of failure of the initial surgery.

RESULTS

The retina was reattached with a single operation in 21 eyes in group I (87.5%) and 19 eyes in group II (86.4%) (P=0.91). The causes of anatomical failure in both groups were proliferative vitreoretinopathy (4 cases) and secondary tears or tears not seen on initial examination (2 cases). For patients in group I, secondary surgery consisted of total vitrectomy with encircling buckle. Patients in group II underwent an additional vitrectomy (peeling of vitreoretinal proliferation, and silicone oil tamponade as necessary). After a mean follow-up of 12 months, the final examination noted a reattached retina in 23 eyes in group I (95.84%) and 21 eyes in group II (95.45%) (P=0.95). The final visual results were identical at comparable follow-up periods. Indeed, the final visual acuity was similar in the two groups with nearly 40% of patients having recovered visual acuity between 1/10 and 5/10 (P=0.98).

CONCLUSION

With regard to surgical treatment of pseudophakic retinal detachment, vitrectomy with internal tamponade provides anatomical and functional results comparable to those obtained with external surgery.

Refractive change caused silicone oil adhesion to the intraocular lens following Nd:YAG posterior capsulotomy

A 32-year-old female who had undergone the silicone oil removal procedure presented with visual disturbance in her left eye. Several months previous, she had cataract surgery in a private clinic, and a month later she had a Nd:YAG laser procedure for posterior capsulotomy. The slit-lamp examination revealed silicone oil droplets that had adhered to the intraocular lens where the posterior capsulotomy was performed. She had experienced high myopia as a manifestation of the resulting refractive changes. We replaced the previous intraocular lens with a new acrylic intraocular lens with resulting improvement to her vision. Here we report the case of a female patient with a history of silicone oil removal surgery where the resulting silicone bubbles had not been removed thoroughly and remained in the vitreous cavity. These bubbles subsequently adhered to the intraocular lens following YAG laser posterior capsulotomy, resulting in refractive changes. We recommend that implanting a silicone intraocular lens in anyone with a history of the silicone oil removal procedure or who has a possible history of silicone oil use should be avoided.

Combined pars plana vitrectomy and lens management in complex vitreoretinal disease

Concurrent cataract and vitreoretinal disorders are relatively common. Additionally, a considerable number of phakic eyes develop visually significant cataract following pars plana vitrectomy. The ophthalmic literature is replete with reports of a combined procedure consisting of simultaneous cataract extraction, intraocular lens implantation, and pars plana vitrectomy to treat a wide range of vitreoretinal disorders and co-existing cataracts. Historical concerns of increased risk of complications with the combined procedure have been shown not to be clinically significant. The combined procedure offers the advantages of a single procedure, including faster recovery time and cost effectiveness. Earlier reports of the combined procedure describe pars plana lensectomy and extracapsular cataract extraction as techniques for cataract extraction. Currently, phacoemulsification with implantation of a foldable posterior intraocular lens implantation has become the preferred technique of cataract removal. With advances in instrumentation and surgical techniques, the combined procedure offers a safe and effective way to manage concurrent cataract and complex vitreoretinal disease.

Outcome of phacoemulsification in patients with uveitis

AIMS

To examine the visual outcome and identify risk factors for postoperative uveitis, macular oedema and neodymium-doped yttrium aluminium garnet (Nd:YAG) capsulotomy after phacoemulsification and intraocular lens (IOL) implantation in patients with uveitis.

METHOD

This is a retrospective review of the medical records of 101 eyes of 101 patients. One eye was randomly selected for inclusion in patients who had bilateral surgery. Patients with juvenile arthritis, keratouveitis and lymphoma-associated uveitis were excluded.

RESULTS

At the first postoperative and final visits, visual acuity was significantly better (p<0.001), and 64.4% and 71.3% of patients, respectively, had achieved >or=2 Snellen's lines of visual improvement. The cumulative probability of doubling of the visual angle was 52% over 6 years of follow-up, and this occurred at a higher rate in the presence of preoperative retinal or optic nerve lesions (HR (95% CI) 4.49 (1.41 to 14.29)). Within 3 months after operation, uveitis was more likely to develop in female patients (OR (95% CI) 6.21 (1.41 to 27.43)) and in the presence of significant intraoperative posterior synechiae (OR (95% CI) 8.43 (1.09 to 65.41)); macular oedema was more likely to develop in patients who developed postoperative uveitis (OR (95% CI) 7.45 (1.63 to 34.16)). Nd:YAG capsulotomy occurred at a higher rate in patients aged <or=55 years (HR (95% CI) 2.28 (1.06, 4.93)) and in those with hydrogel IOLs (HR (95% CI) 3.71 (1.04 to 13.20)), and occurred at a lower rate in patients who had prophylactic systemic corticosteroids (HR (95% CI) 0.25 (0.11 to 0.59)), with plate-haptic silicone IOLs (HR (95% CI) 0.23 (0.08 to 0.64)) and three-piece silicone IOLs (HR (95% CI) 0.19 (0.05 to 0.74)) in comparison to those with polymethylmethacrylate IOLs.

CONCLUSION

Most patients with uveitis achieve improved visual acuity after phacoemulsification, but an increasing rate of visual loss is observed in those with pre-existent macular or optic nerve lesions. Identifying patients who are at risk of postoperative complications should help in patient counselling and to pre-empt these complications by using preoperative prophylactic corticosteroids, careful IOL selection and postoperative intensive corticosteroids.

Pseudophakic retinal detachment

Pseudophakic retinal detachment is a rare, but potentially serious, complication of cataract surgery. The incidence of pseudophakic retinal detachment following current surgical techniques of cataract extraction, including extracapsular cataract extraction by nuclear expression and phacoemulsification, is lower than that found after intracapsular cataract extraction. The risk of pseudophakic retinal detachment appears to be increased in myopic patients, in those patients in whom vitreous loss had occurred at the time of cataract surgery, and in patients undergoing Nd:YAG posterior capsulotomy. Most cases present to the clinician when the macula is already detached and the central vision is affected. When evaluating patients with pseudophakic retinal detachment, the fundal view is often impaired by anterior or posterior capsular opacification, reflections related to the intraocular lens, or poor mydriasis. Scleral buckling, pneumatic retinopexy, and primary pars plana vitrectomy, with or without combined scleral buckling, are the surgical techniques used to treat pseudophakic retinal detachment. Anatomical success rates are high after vitreo-retinal surgery for pseudophakic retinal detachment, although a smaller proportion of patients recover good vision following surgery.

Cataract surgery results after pars plana vitrectomy

Continuous refinements in vitreoretinal surgical techniques and an increasing number of posterior segment disorders are being successfully managed with pars plana vitrectomy (PPV). This has resulted in an increase in the number of vitrectomized eyes seen by cataract surgeons. Cataract surgery in previously vitrectomized eyes has been reported to be more challenging than in eyes without previous vitrectomy. Special considerations and precautions are often required before, during, and after the surgery to successfully address these challenges. Several studies have reported that phacoemulsification with intraocular lens implantation after PPV is a relatively safe procedure that can improve visual acuity and quality of life. The extent of visual improvement may be limited only by retinal comorbidity.

Post cataract-intraocular lens (IOL) surgery opacification

Intraocular lens (IOL) implantation has no doubt been one of the most satisfying advances of medicine. Millions of individuals with visual disability or frank blindness from cataracts had and continue to have benefit from this procedure. It has been reported by ophthalmologists that the modern cataract-intraocular lens (IOL) surgery is safe and complication-free most of the time. This makes the watchword for any cataract surgeon to be 'implantation,' 'implantation,' 'implantation.' In the mid-1980s, as IOLs were evolving rapidly, the watchword of the implant surgeon was 'fixation,' 'fixation,' 'fixation.' Most techniques, lenses and surgical adjuncts now allow us to achieve the basic requirement for successful IOL implantation, namely long-term stable IOL fixation in the capsular bag. However despite this advancement some items 'slipped through cracks.' In this article, we would like to alert the reader to a new watchword, namely 'opacification,' 'opacification,' 'opacification.' Here we will be talking about the good, the bad, and the ugly. Examples of the 'good' include the recent successes now being achieved in reducing the incidence of posterior capsule opacification. Examples of the 'bad' include various proliferations of anterior capsule cells, problems caused by silicone oil adherence to IOLs and problems with piggyback IOLs. The 'ugly' include the sometimes striking and often visually disabling opacifications occurring on and within IOL optics, both on some modern foldable IOLs as well as a poly(methyl methacrylate) (PMMA) optic degradation occurring with some models a decade or more after implantation.

Combined phacoemulsification and transpupillary drainage of silicone oil: results and complications

AIM

To review retrospectively 74 consecutive cases of combined phacoemulsification and transpupillary drainage of silicone oil.

METHODS

Candidate patients for intraocular silicone oil removal and cataract extraction underwent combined phacoemulsification and transpupillary drainage of silicone oil through a planned posterior capsulorrhexis and without the use of a pars plana infusion line.

RESULTS

The retina remained attached in 59 (79.7%) patients postoperatively. In this success group, the postoperative visual acuity improved in 42 (71.2%) patients. There was no association between age, duration of silicone oil tamponade, preoperative diagnosis, macular status or number and nature of previous surgery, and the incidence of redetachment following silicone oil removal.

CONCLUSION

Combined phacoemulsification and transpupillary drainage of silicone oil is a safe and reliable technique that offers the main advantage of diminished surgical trauma.

Acrylic intraocular lens placement in conjunction with pars plana vitrectomy

PURPOSE

To report the results of placing a foldable acrylic intraocular lens through a clear cornea incision in eyes undergoing pars plana vitrectomy.

METHODS

This interventional case series is a retrospective report of 15 eyes of 15 consecutive patients undergoing foldable (acrylic) intraocular lens insertion in conjunction with pars plana vitrectomy in a single academic institution. Outcome measures included visual acuity and complications.

RESULTS

The intraocular lens was successfully implanted and retained in position in all 15 cases. The intraocular lens did not pose difficulty in examining the fundus or cause any vitreoretinal complications. With mean follow-up of 4.5 months (range, 1--10 months), final median postoperative visual acuity range was 20/200 (range, 20/40--2/200) and consistent with the level of vitreoretinal disease.

CONCLUSION

Acrylic intraocular lenses may be safely implanted in conjunction with pars plana vitrectomy in selected cases.

Silicone oil-intraocular lens interaction: which lens to use?

AIM

To determine a suitable intraocular lens for implantation in patients at high risk of lens exposure to silicone oil in their lifetime.

METHODS

PMMA, AcrySof, AR40, AQUA-Sense, and Raysoft lenses were examined. Each lens was immersed for 5 minute intervals in balanced salt solution (BSS), in stained silicone oil, and again in BSS before being photographed in air and in BSS. Percentage silicone oil coverage of the lens optic was determined.

RESULTS

The mean percentage coating (MPC) for the lens biomaterials ranged from 5.2% to 21.5%. The Raysoft lens had significantly less oil coverage when statistically compared with the other lens types (p < 0.001).

CONCLUSION

A Raysoft (Rayner) lens is a suitable lens for implantation in patients who are at risk of severe vitreoretinal disease.

Effect of large positioning holes on capsule fixation of plate-haptic intraocular lenses

PURPOSE

To compare the centration and fixation of silicone plate-haptic intraocular lenses (IOLs) with different-sized positioning holes.

SETTING

Eye Clinic of the Johannes Gutenberg-University Mainz, Mainz, Germany.

METHODS

In a prospective randomized study, 51 Chiroflex C10 and 56 Chiroflex C11 IOLs were implanted under standardized conditions by the same surgeon. The IOL position was documented at the end of surgery and by retroillumination on the first day and 5 months postoperatively. The positioning-hole area was evaluated by ultrasound biomicroscopy (50 MHz) 5 months postoperatively.

RESULTS

One day postoperatively, no IOL in either group was decentered more than 1.0 mm. After 5 months, 33% of the C10 and 42% of the C11 IOLs were decentered between 0.5 and 1.0 mm, and 11% of the C10 and 8% of the C11 IOLs were decentered more than 1.0 mm (maximum 1.23 mm and 1.41 mm, respectively). Up to the first postoperative day, 20% of the C10 and 22% of the C11 lenses were rotated more than 15 degrees. At 5 months, an additional 15% of the C10 and 19% of the C11 lenses were rotated. Ultrasound biomicroscopy showed no tissue or capsule adhesion in the holes in most cases (85% C10 group; 71% C11 group). No difference was statistically significant.

CONCLUSIONS

Larger positioning holes did not prevent IOL decentration or rotation; thus, this IOL design appears unsuitable for correcting astigmatism. Because tissue in the positioning hole was rare with both lens types, it is doubtful that enlarged plate-haptic perforations will prevent IOL luxation into the vitreous cavity after capsulotomy.

Solvent for removing silicone oil from intraocular lenses: experimental study comparing various biomaterials

PURPOSE

To evaluate the effectiveness of a perfluorocarbon-perfluorohexyloctane (PFHO)-in removing silicone oil from different intraocular lenses (IOLs) and determine whether any removal technique enhances the removal of silicone oil.

METHODS

Six IOL materials were analyzed: standard poly(methyl methacrylate) (PMMA), heparin-surface-modified (HSM) PMMA, AcrySof, 2 polyHEMAs with different water contents, and a second-generation SLM-2 silicone. One or 2 microL of a highly viscous silicone oil (5700 cs) was applied to the center of each IOL optic. Perfluorohexyloctane (2 mL) was then used to remove the silicone oil by 1 of 3 techniques: immersion of the IOL in PFHO; irrigation of the silicone oil with a small, blunt cannula; mechanical wiping with a PFHO-saturated Merocel swab (used only when irrigation failed). Next, each IOL was examined by light and scanning electron microscopy. The expanse of silicone oil residue remaining on the IOLs was objectively quantified using an integrated computerized analysis system combined with energy-dispersive spectrometry.

RESULTS

After application of 1 microL silicone oil, immersion in PFHO did not remove silicone oil from any IOL material. Irrigation with PFHO removed the silicone oil from the HSM PMMA and polyHEMA IOLs, but oil remained on the other lens materials. Mechanical wiping was necessary to remove the oil from the PMMA, AcrySof, and silicone IOLs. Attempts to remove 2 microL of silicone oil produced similar results. Although mechanical wiping of the AcrySof IOL removed all silicone oil, a slight residue remained on the PMMA and silicone IOLs. The PFHO irrigation removed significantly more silicone oil from the HSM PMMA than the unmodified PMMA IOL (P =.001). More silicone oil was removed from polyHEMA IOLs than from the AcrySof or silicone IOLs (P =.05).

CONCLUSION

Although PFHO can remove silicone oil, it is of limited usefulness. The effectiveness of PFHO depends on the removal technique, IOL material, and amount of silicone oil present. Based on these results, we recommend PFHO irrigation followed by mechanical wiping with a PFHO-saturated swab.

Removing silicone oil droplets from the posterior surface of silicone intraocular lenses

A 67-year-old woman had droplets of silicone oil adhering to her silicone intraocular lens (IOL) resulting from a previous silicone oil tamponade. A lens hook and intraocular irrigation were used in conjunction by inserting an infusion cannula to remove the droplets. This restored clarity of the visual axis, improved visual acuity, and eliminated the need for IOL replacement. The technique is simple and less invasive than IOL exchange and may become the preferred way to remove silicone droplets from an IOL.