Capsular Bag Preservation for Fixation of Late Intraocular Lens Dislocations.

Condensation on Polymethylmethacrylate, Acrylic Polymer, and Silicone Intraocular Lenses after Fluid-Air Exchange in Rabbits

Spontaneous late dislocation of intraocular lens within the capsular bag in pseudoexfoliation patients

This Issue At A Glance

To report a detailed spectroscopic analysis of explanted hydrophilic acrylic intraocular lenses (IOLs) that were removed because of postoperative opacification of the lens optic. Thirteen Hydroview H60M (Bausch & Lomb Surgical) IOLs were explanted from 13 different patients on average 56 months after phacoemulsification and IOL implantation. All patients had decreased visual acuity because of a fine granularity of the optical surface of the IOLs. The surface was investigated by gross, microscopic, histochemical and scanning electron microscopic analysis, and the elemental composition of the opacified IOLs was determined by X-ray fluorescence spectroscopy (XRF). The spectrograms were compared to three different originally packed and never-implanted hydrophilic acrylic IOLs. Light and scanning electron microscopy of the optical surface of explanted IOLs revealed multiple fine granular deposits varying in size and shape that were positive for alizarin red. XRF confirmed that the explanted IOLs contained not only the previously reported calcium and phosphorous (calcium apatite), chlorine, silicone, sodium, aluminum and magnesium but also iron, sulfur, potassium as well as lesser amounts of iodine, zinc, strontium and yttrium. This is the first spectroscopic analysis determining the content of more than 10 elements of explanted and originally packed never-implanted hydrophilic acrylic IOLs. The possible origin of the different elements obtained from the spectrograms and their implications are discussed.

Cataract surgery in patients with diabetes

To assess the outcome of simultaneous phacoemulsification, pars plana vitrectomy and intraocular lens (IOL) implantation in eyes with macular hole. A retrospective study was conducted in 38 eyes (36 patients) after combined phacoemulsification, insertion of a posterior capsule IOL and pars plana vitrectomy. The macular hole was successfully closed in 32 of the 38 eyes (84%). In six eyes (16%) the hole failed to close and one eye underwent a second operation. Vision improved by two or more Snellen lines in 29 eyes (73%), there was no change in seven eyes (18%), and visual acuity decreased in two eyes (5%). Intraoperative and postoperative complications included retinal tears in nine eyes (24%), posterior capsule rupture in two eyes (5%), transient postoperative increase of intraocular pressure in eight eyes (21%), and posterior capsule opacification in five eyes (13%). Combining phacoemulsification, IOL insertion and pars plana vitrectomy for macular hole repair can reduce the need for cataract surgery in the future, decrease costs, shorten postoperative recovery time and allow for clearer intraoperative visualization, making the procedure safer and more effective.

To determine Nd:YAG laser energy requirements for posterior capsulotomy and intraocular lens (IOL) damage threshold for foldable acrylic IOLs as compared to traditional polymethylmethacrylate (PMMA). MATERIALS AND PROCEDURES: Four groups of five-six fresh canine cadaver eyes were used in this study. The groups included (1) unaltered eyes (2) aphakic eyes (3) eyes implanted with PMMA IOLs, and (4) eyes implanted with acrylic IOLs. Laser energy was delivered to the posterior capsule in grid fashion for 10 sites each of five levels of laser energy ranging from 0.5 mJ to 9 mJ. Number of successful capsulotomy sites was recorded based on slit-lamp observation. Sites of IOL damage were evaluated using scanning electron microscopy (SEM). Statistical analysis of number of capsulotomies and IOL defects per laser energy level was conducted among and between groups using anova with Tukey's HSD test. When comparing groups (a) including all energy levels (n = 25) and (b) by specific energy levels (n = 5), there was no significant difference (P < 0.05) in number of successful capsulotomy sites between IOL types. The 50% incidence threshold for successful capsulotomy was 2.74 mJ for acrylic IOLs and 2.64 mJ for PMMA IOLs. Energy-dependent damage to both types of IOL was detected for medium, high-medium, and high laser energy. Calculated 50% damage threshold was 4.9 mJ for acrylic IOL and 5.7 mJ for PMMA IOL. Damage to the IOL varied subjectively between IOL type, but there was no significant difference in number of defects caused, with the exception of high-medium energy. Both posterior lens capsules and IOLs were disrupted in an energy-dependent manner with minimal difference in number of capsulotomy sites or damage to the IOL between acrylic and PMMA IOLs. A therapeutic margin between capsulotomy threshold (2.6-2.7 mJ) and IOL damage threshold (4.9-5.7 mJ) was determined to reliably achieve capsulotomies with minimal IOL damage for both acrylic and PMMA IOLs in normal canine cadaver eyes.

Management of Dislocated Intraocular Lenses

Intraocular lens changes after short- and long-term exposure to intraocular silicone oil: An in vivo study

Purpose: To compare complications between forceps and injector delivery for Acrylic multipiece intraocular lens (IOL) in phacoemulsification. Study Design: Randomized Clinical Trial. Place & Duration of Study: Yaqin Vision Eye center from October 2002 to June, 2017. Material and Methods:All patients undergoing routine phacoemulsification with implantation of foldable acrylic multipiece IOL (Acrysof MA60 AC, Alcon, USA) were included in the study. The patients were divided into two groups according to the method of insertion of the IOL. Group A included patients undergoing foldable implantation with forceps while group B included patients in which injector was use to implant the IOL. Total 820 patients were included in study. Group A included 408(49.76%) patients and 412 (50.24%) patients were included in Group B. Patients undergoing phaco trabeculectomy, phaco vitrectomy, lensectomy and implantation of all other types of IOL, were excluded from the study. Any complications arising during insertion of IOL were recorded in the electronic records of the patients. Results were analyzed using SPSS version 20. Results: Out of 820 patients Group A included 408 patients with average age of 63 ±12.2 yrs with 189 (46.32%) males and 219 (53.68%) females while group B included 412patients with average age of 60 ±16.4 yrs with 182 (44.17%) males and 230 (55.83%) females. In group A there were 392 (96 %) IOLs implanted in the bag and 16 (4%) in the sulcus. In group B there were 396 (96%) IOLs implanted in the bag and 16 (4%) in the sulcus. Forceps delivery needed enlargement of incision to 3.5 mm for IOL insertion with no insertion related complication. While Injector delivery needed only 3.0 mm enlargement of wound with few injectors related complications. These included optic and haptic damage 2(0.48%), flipping of IOL back to front 4(0.97%) and posterior capsular rent (PCR) with haptic 1(0.24%) while injecting. Injector insertion allowed insertion of IOL in bag in cases of small PCR due to deep and stable chamber during IOL insertion compared to forceps delivery.These complications with injectors happened in early transition from forceps to injector technique. Conclusion: Delivery of multipiece IOL with injector has more complications compared to forceps delivery. Therefore practice of IOL insertion with injector in wet lab is recommended before switching to this technique. Keywords: Phacoemulsification, Acrylic intraocular lens, Injector, Forceps.

BackgroundThis study aimed to investigate the safety and efficacy of the Yamane technique (flanged intrascleral haptic fixation with double-needle technique /FIHFT) for three-piece intraocular lens (IOL) implantation in Egyptian patients diagnosed with Marfan syndrome (MFS) presented with subluxated lenses (ectopia lentis, EL).MethodsThis was a retrospective evaluation of thirty-three patients who were diagnosed with MFS and had subluxated lenses in a total of forty eyes. Seven of these patients had bilateral subluxation. Lensectomy or phacoemulsification was performed with limited anterior vitrectomy, followed by IOL implantation using the FIHFT method. Data was collected from medical records, including preoperative and postoperative corrected distant visual acuity (CDVA) using logarithm of the minimal angle of resolution (log MAR), preoperative and postoperative refractions, intraoperative and postoperative complications, and follow-up periods.ResultsThe mean age of patients in the study was 30.79 years, with a mean follow-up of 23.9 months. Post-surgery, the refractive sphere decreased significantly from -9.1 ± 1.4 diopter (D) to -1.4 ± 0.7 D, and cylinder measurements dropped from -4.5 ± 0.8 D to -1.4 ± 0.6 D. The spherical equivalent (SEQ) also declined from -11.4 ± 1.5 D to -2.1 ± 0.8 D. The CDVA improved from 0.80 ± 0.32 to 0.18 ± 0.10 log MAR (P < 0.001). No intraoperative complications were identified. Postoperative complications included IOL decentration (12.5%), vitreous hemorrhage (7.5%), IOL slippage (5%), IOL tilt (5%), and retinal detachment (RD) (5%). Further surgical procedures were necessary for only four cases (10%), all of which had positive outcomes. IOL tilting and slippage occurring at average ages of 18 and 19 years, respectively. No other complications, such as hypotony, elevated intraocular pressure (IOP), corneal edema, iritis, IOL dislocation, cystoid macular edema (CME) or endophthalmitis, were reported.ConclusionsThe Yamane technique has proven effective and safe for treating subluxated lenses in Egyptian patients with Marfan Syndrome, resulting in improved visual acuity with minimal complications, mostly minor and manageable. Comprehensive fundus examinations before and after surgery are essential for promptly identifying retinal breaks and reducing the risk of retinal detachment. IOL tilting and slippage are more common in younger patients.

Capsulorhexis ovaling and capsular bag stretch after rigid and foldable intraocular lens implantation: Experimental study in pediatric human eyes

Introduction: The selection of intraocular lens is still debatable in paediatric eye. Due to low cost and fewer intra-operative complication hydrophilic acrylic intraocular lens are implanted in volume in low income countries. There is lack of comparative study of this type of lens with hydrophobic lens in paediatric population.&#x0D; Aims: To compare the outcomes of hydrophilic acrylic lens and hydrophobic acrylic lens in paediatric cataract surgery.&#x0D; Methods: Out of 48 eyes included in the study, the Group A (n =24) eyes were implanted with acrylic hydrophilic intraocular lens, and the Group B (n =24) were implanted with acrylic hydrophobic intraocular lens. The children were evaluated pre, intra and postoperatively for different parameter.&#x0D; Results: The mean age was 6.6±2.7 years at the time of surgery. The most common type of cataract was zonular (58% in Group A and 50% in Group B). Postoperatively, corneal edema was seen in 7(29%) eyes in group A and in 2(8%) eyes in group B. The mean follow-up was 16.9±2.9 months. At one year, the position of the intraocular lens was in the capsular bag in 20 eyes (88.33%) and 24 eyes (100 %) in the group A and B, respectively. Clear visual axis was present in 22 eyes in Group A and 24 eyes in Group B. Posterior capsule opacification occurred in 12(50%) eyes in Group A and 6(25%) eyes in Group B. Two (8.3%) eyes in group A underwent surgical membranectomy due to visual axis opacification. The mean LogMAR visual acuity was 0.56 and 0.52 in group A and B respectively at one year.&#x0D; Conclusion: Hydrophilic acrylic intraocular lens are good alternative to hydrophobic intraocular lens in Nepal in the treatment of paediatric cataract.

Glare Secondary to Damaged IOL

According to the 2015–2019 survey by the National Programme for Control of Blindness and Visual Impairment, uncorrected aphakia accounts for 1.7% of blindness and vision impairment in adults aged >50 years in India.[1] Anisometropia, aniseikonia, prismatic distortion of images (jack-in-the-box phenomenon) and the weight of high hyperopic spectacles demands rehabilitation in surgical aphakia with an intraocular lens (IOL) implantation. IOLs provide a better field of vision and less image disparity, and are more acceptable cosmetically. The standard of care of in-the-bag implantation of an IOL, may not be feasible in circumstances where there is a lack of posterior capsular support. Such instances are not uncommon in a regular cataract surgeon’s practice. Further recourse depends on the presence or absence of sulcus support. While, in the presence of an adequate sulcus support, a foldable 3-piece or a rigid polymethyl methacrylate (PMMA) IOL is preferred, in its absence, the choice of IOL fixation depends on the surgeon’s expertise. We congratulate the authors for summarizing the desired options for aphakia management by the anterior and posterior segment surgeons, in their study “Preferred practice patterns in Aphakia management in adults in India - A Survey”.[2] Although this study elaborates on the preferred site of IOL fixation being the iris and scleral-fixated IOLs by anterior and posterior segment surgeons, respectively, the results cannot be extrapolated to a larger population, considering the minimal response rate (4.8%). The primary indication for secondary IOL, age of the patient at surgery, associated ocular and systemic conditions, level of training of surgeons, and the availability of different types of IOLs should also be considered when such a survey is being conducted. Optical correction is a critical component of visual rehabilitation in aphakia. There are pros and cons to each of the modalities of IOL fixation. Owing to the higher risk of hyphema, secondary glaucoma and corneal endothelium decompensation, either scleral-fixated or iris-fixated IOLs are being preferred over the use of angle-fixated anterior chamber IOLs nowadays.[3] The decision to use iris-fixated or scleral-fixated IOLs depends on the expertise of the surgeon.[45] The visual outcome in both types of IOL fixation are comparable at variable follow-up periods, although long-term prospective studies are required to confirm the same.[5678] Each of these methods have inherent complications associated with them. Iris-fixated IOLs, either anteriorly or posteriorly, are associated with iris erosion, pigment dispersion, corectopia, hyphema, IOL subluxation, cystoid macular edema, chronic uveitis and secondary glaucoma.[58] In addition to the aforementioned complications, scleral-fixated IOLs, either sutured or suture-less, are associated with vitreous hemorrhage, haptic exposure, retinal detachment, scleral thinning and IOL tilting and/or dislocation.[59] As opposed to the in-the-bag IOL and angle-fixated anterior chamber IOL (ACIOL), the procedure for iris-fixated and scleral-fixated IOLs is technically challenging, has a steep learning curve and needs expertise. The long-term stability of the these IOLs as well as complications are yet to be studied prospectively. Nevertheless, these results cannot be extrapolated to the pediatric aphakic population. Age, size of the eyeball, corneal diameter, primary indication of aphakia, eye growth, systemic associations, and high prediction errors are factors to be considered while planning IOL implantation in children. Primary IOL implantation is usually discouraged in children with small eyes (short axial length/microcornea) and those with associated anterior and posterior segment pathologies. When children reach the appropriate age, and their eyes are of the adequate size with open angles on gonioscopy and have no contraindications, a secondary three-piece IOL or a PMMA IOL in-the-sulcus/in-the-bag can be planned.[10] When sulcus examination becomes difficult clinically, ultrasound biomicroscopy of the anterior segment can be done. This provides the surgeon with information on the status of ciliary sulcus and its surrounding tissue preoperatively.[10] The vigilance on the postoperative course in children should be high as they are at a risk of excessive postoperative inflammation and rise in intraocular pressure. In specific cases such as ectopia lentis caused by Marfan syndrome, it is preferrable to leave the children aphakic and rehabilitate them with contact lenses or spectacles. Thus, for a customized approach to manage a case of aphakia, weighing the risks and benefits of the procedure is encouraged. Various factors to be considered are age, indications, contraindications, site of IOL fixation, IOL POWER calculation formula, IOL material/designs and expertise in the procedure. The historic Latin phrase, Primum non nocere, meaning, “First, do no harm,” should be respected, and selected cases should be left aphakic and rehabilitated with contact lenses or spectacles, rather than implant an IOL and cause irreversible damage due to glaucoma, corneal decompensation and retinal detachment.