Evaluation of Lens Capsule Stability Using Capsular Tension Ring, Iris Retractor, and Capsule Expander Using a Porcine Model With Zonular Dehiscence.

Purpose: We evaluate the efficacy of capsular tension rings (CTRs), iris retractors (IRs), and capsule expanders (CEs) in stabilizing the lens capsule under different degrees of zonular dehiscence using a porcine model. Methods: We developed an experimental model that can be used to observe the dynamics of lens capsules with different degrees of zonular dehiscence during phacoemulsification and aspiration (PEA). PEA was performed without any aid (control) and with devices. A CTR was used for a dehiscence of 30°, 45°, 60°, 90°, 120°, 150°, and 180° and one to four IRs or one to three CEs were used for a dehiscence of 90°, 120°, and 180°. The retention rate, calculated as the area of the capsular bag during PEA divided by the area before zonular dissection, and the number of lens fragments dropped into the vitreous cavity during PEA were examined and compared among the control and experimental groups. Results: The retention rate increased significantly with the use of devices compared to the control (P < 0.05). The number of dropped lens fragments decreased by one or less with the use of CTR, one IR, or one CE for 90°, two IRs, or one or two CEs for 120°, and three or four IRs, or two or three CEs for 180° of zonular dehiscence. Conclusions: The experimental porcine eye model with zonular dehiscence makes it possible to observe the entire configuration of the lens capsule, and demonstrates differences in the efficacy of capsular bag retention with CTR, IR, and CE.

Objective classification of zonular weakness based on lens movement at the start of capsulorhexis.

PURPOSE: To quantify zonular weakness based on lens movement at the start of continuous curvilinear capsulorhexis (CCC) and establish a classification system for it. SETTING: Kozawa Eye Hospital and Diabetes Center, Mito, Japan. DESIGN: Retrospective interventional case series. METHODS: We examined 402 consecutive eyes of 316 patients who underwent CCC, phacoemulsification and aspiration (PEA), and intraocular lens (IOL) implantation. The movement of the lens capsule was measured using images from video recordings of the CCC procedure. Zonular weakness was classified based on the shifted distance: Grade I, less than 0.20 mm; Grade II, 0.20-0.39 mm; and Grade III, greater than 0.40 mm. For each of these grades, we examined the use of the capsule stabilization device during PEA, the surgical procedure for lens removal, and IOL fixation. RESULTS: We classified 276 eyes (68.6%) as Grade I, 102 eyes (25.4%) as Grade II, and 24 eyes (6.0%) as Grade III. As the grade increased, the use of the capsule stabilization device in PEA and scleral suture fixation of IOL increased. CONCLUSIONS: Zonular weakness was quantified by measuring the movement of the lens capsule. An objective classification of zonular weakness based on lens movement may be useful for selecting the appropriate device and procedure during cataract surgery.

Phacoemulsification without hydrodissection: Semi-crater and split technique.

UNLABELLED: We present a semi-crater sculpting and split technique for simple nucleus removal and hydrodissection-free phacoemulsification. In this technique, the crater sculpting is done in half the nucleus only and emulsified before nucleus rotation. The remaining half of the nucleus is freed from the capsule and then rotated to the opposite side of the phaco tip and emulsified. This technique can be easily performed without hydrodissection because emulsifying half the nucleus creates a free space. It was used in 19 198 eyes between 2000 and 2013 and enabled stable phacoemulsification, regardless of the surgeon's experience. The technique prevents hydrodissection-related complications, such as posterior capsule rupture caused by high intraocular pressure changes, and reduces the stress on the zonule during nucleus rotation. FINANCIAL DISCLOSURE: Neither author has a financial or proprietary interest in any material or method mentioned.

Modified capsule expander implantation to reposition and fixate the capsular bag in eyes with subluxated cataractous lenses and phacodonesis: intermediate-term results.

PURPOSE: To report the intermediate-term results of capsule stabilization for scleral fixation with implantation of the Yaguchi hook, a modified capsule expander stabilization hook. SETTING: Department of Ophthalmology, School of Medicine, University of Showa, Fujigaoka Rehabilitation Hospital, Yokohama, Japan. DESIGN: Retrospective case series. METHODS: Patients with zonular dialysis and phacodonesis were followed postoperatively for at least 2 years. All eyes had phacoemulsification and aspiration using an ordinary capsule expander and in-the-bag implantation of an intraocular lens (IOL). Capsule expanders were removed after the residual cortex was removed, and the capsular bag was fixated to the scleral wall via the ciliary sulcus using the modified capsule expander stabilization hook. Preoperative findings, intraoperative complications, and postoperative courses were examined. RESULTS: The mean age of the 11 patients (11 eyes) was 72.2 years ± 10.5 (SD); 5 patients were men. The mean postoperative follow-up was 48.6 ± 13.6 months. The zonular dialysis range was 90 to 180 degrees in 1 eye, 180 degrees in 4 eyes, and 180 to 270 degrees in 1 eye. In 5 eyes, severe phacodonesis was observed without obvious zonular dialysis. In all eyes, the capsular bag and IOL were well centered without severe intraoperative or postoperative complications. CONCLUSION: The modified capsule expander stabilization hook provided good centration and stabilization of the capsule-IOL complex in eyes with severely weak zonular fibers. FINANCIAL DISCLOSURE: Dr. Yaguchi, who is the inventor of the modified capsule expander, has received financial support from Handaya, Tokyo, Japan. No other author has a financial or proprietary interest in any material or method mentioned.

Effect of decentration on the optical performance in multifocal intraocular lenses.

AIMS: To evaluate the influence of decentration on optical performance in multifocal intraocular lenses (IOLs) using eye models. METHODS: This study evaluated 4 types of multifocal IOLs (ReSTOR SA60D3, Alcon; TECNIS Multifocal ZM900, AMO; ReZoom, AMO; SFX-MV1, Hoya). The evaluations were based on measurements of the near and far modulation transfer function (MTF) and visualized actual near images (newspaper) using eye models with the IOL horizontally displaced 0, 0.25, 0.5, 0.75 and 1.0 mm from the center. RESULTS: For the diffractive ReSTOR the near MTF decreased with increasing decentration. The near images (newspaper characters) became difficult to distinguish at a decentration of 1.0 mm. For the diffractive ZM900, the near and far MTFs gradually decreased with increasing decentration. For the refractive ReZoom and SFX-MV1, we observed almost no change in the near MTF from a decentration of 0-1.0 mm. However, the far MTF clearly decreased starting at a decentration of 1.0 mm for ReZoom and 0.75 mm for SFX-MV1. CONCLUSION: The MTFs and near images are affected to a different extent depending on the design of multifocal IOLs; clinically relevant effects are not to be expected up to a decentration of 0.75 mm.

Repositioning and scleral fixation of subluxated lenses using a T-shaped capsule stabilization hook.

We describe a T-shaped capsule stabilization hook (modified capsule expander [M-CE]) used for repositioning and scleral fixation of the lens capsule of subluxated lenses. The 5-0 polypropylene device is flexible and attached to a curved needle. The contact portion is bent at 1.25 mm, and the end bifurcates in a T configuration to form a 3.75 mm footpad from which the capsular bag can be suspended. Modified capsule expanders were implanted in 4 eyes of 4 patients with subluxated cataractous lenses and provided excellent support and centration of the intraocular lens (IOL)-capsular bag complex. The IOLs remained well centered and stable. The corrected distance visual acuity improved to at least 20/20 in all patients after surgery. Thus, M-CEs were effective in fixating the lens capsule to the sclera in patients with significant zonular weakness.

In vitro assessment of the cytotoxicity of anti-allergic eye drops using 5 cultured corneal and conjunctival cell lines.

The aim of this study was to evaluate the cytotoxicity of anti-allergic eye drops for human corneal endothelial cells (HCEC) and commercially available ocular surface cells. A primary HCEC culture was derived from human eye bank specimens. SIRC (rabbit corneal epithelium), BCE C/D-1b (bovine corneal epithelial cells), RC-1 (rabbit corneal epithelium), and Chang (human conjunctival cells) were obtained commercially. The WST-1 assay was used to measure HCEC viability, and the viability of other cells was measured using the MTT assay. Cells were treated with 7 commercially available anti-allergic eye drops for 48 h and cell viability was measured and calculated as a percentage of control. The degree of toxicity for each eye-drop solution was based on the cell viability score (CVS). HCECs treated with a 1000-fold dilution of the eye-drop solution had a viability score of 67% for Rizaben and ≥80% for the other solutions with Zepelin being the least toxic. Cell viability in response to eye-drop solutions preserved with benzalkonium chloride (BAK) was dependent on the concentration of the drug solution and exposure time. Treatment of ocular surface cells with a 20-fold dilution of the eye-drop solution resulted in the following order of cell viability as determined by their CVS: Zepelin > Ketas = Zaditen ≥ Tramelas PF = Patanol ≥ Rizaben ≥ Livostin. This order was similar to that observed for HCECs, and cell viability was found to be concentration-dependent. Based on the penetration of the drug into eye tissues, HCECs are only likely to be pharmaceutically damaging in rare cases. Epithelial cell viability depends primarily on the concentration of BAK rather than on the action of the active component in the eye-drop solution. CVS values were useful for comparison of toxicity.

Cytotoxicity of topical medications used for infection and inflammation control after cataract surgery in cultured corneal endothelial cells.

Postoperative vision-threatening corneal edema sometimes occurs after eye surgery, and corneal endothelial damage may be caused or exacerbated by drug toxicity. A range of commercially available antibiotic and anti-inflammatory ophthalmic solutions used postoperatively, namely levofloxacin, moxifloxacin, gatifloxacin, cefmenoxime, diclofenac, bromfenac, pranoprofen, betamethasone, and fluoromethorone, were assessed by using human corneal endothelial cells (HCECs). Propylparaoxybenzoate and methylparaoxybenzoate were also examined. Cell survival after 48 h exposure to the drugs was evaluated using the WST assay. Cefmenoxime and betamethasone were the least toxic antibiotic and anti-inflammatory drug, respectively. Cell survival was concentration dependent and increased markedly to ≥ 80% with dilutions of 100-fold or more. Two preservatives seemed to cause minimal cytotoxicity among those tested. Antibiotic cytotoxicity to HCEC was ranked as cefmenoxime < levofloxacin = gatifloxacin < moxifloxacin, while the toxicity of anti-inflammatory drugs was dependent on benzalkonium chloride and polysorbate. These drugs are unlikely to cause HCEC damage at the concentrations used under the usual conditions. Preservatives are essential ingredients in ophthalmic solutions to control postoperative infection and inflammation and we should be aware of their toxicity as well as efficacy.

Cytotoxicity of five fluoroquinolone and two nonsteroidal anti-inflammatory benzalkonium chloride-free ophthalmic solutions in four corneoconjunctival cell lines.

PURPOSE: Epithelial disorders after eye surgery can result in visual deterioration and patient discomfort. Such disorders may be caused by drug toxicity. In the present study, we evaluated the toxicity of ophthalmic solutions, with or without benzalkonium chloride (BAK) as the preservative, used for postoperative care. METHODS: A range of commercially available antibiotic and anti-inflammatory ophthalmic solutions used postoperatively (ie, levofloxacin, moxifloxacin, gatifloxacin, norfloxacin, tosufloxacin, dibekacin, cefmenoxime, diclofenac, bromfenac, pranoprofen, betamethasone, and fluoromethorone) were assessed in three corneal cell lines and one conjunctival cell line. All antibiotic solutions were BAK free. Cell viability was determined with the 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay after cells had been exposed to the drugs for 48 h. The effects of preservatives on cell viability were also determined. Toxicity was compared using the cell viability score (CVS). RESULTS: Based on results of the MTT assay and CVS, the order of cell viability after exposure to the antibiotic solutions was cefmenoxime ≥ tosufloxicin ≥ dibekacin ≥ levofloxacin ≥ norfloxacin = gatifloxacin = moxifloxacin. For the anti-inflammatory solutions, the order of cell viability was betamethasone ≥ betamethasone + fradiomycin > preservative-free diclofenac ≥ preservative-free bromfenac >> 0.02% fluoromethorone ≥ 0.1% fluoromethorone = diclofenac + preservative = bromfenac + preservative = pranoprofen. The anti-inflammatory drugs were more toxic than the antibiotics. The toxicity of antibiotic drugs against ocular surface cells was dependent on the pharmaceutical components of the solution, whereas that of the anti-inflammatory drugs was dependent on both the pharmaceutical components and the preservatives. CONCLUSION: Postoperative drug-induced epitheliopathy may be caused primarily by anti-inflammatory drugs. CVS is useful in comparing the cytotoxicity of different drugs.

[Evaluation of post intraocular lens implantation detrition of clear corneal incisions using an injector system in porcine eyes].

PURPOSE: To evaluate the detrition of clear corneal incisions (CCIs) after intraocular lens (IOL) implantation using an injector system in porcine eyes. METHODS: Group A: after CCIs were performed with 1.8, 2.0, 2.2, 2.4, and 2.65 mm wide slit knives, a Y-60 H (HOYA) IOL was implanted in the anterior chamber using an injector system. Group B: after CCIs were performed with 2.4, 2.65, 2.8, 3.0, and 3.2 mm wide slit knives, a PY-60 R (HOYA) IOL was implanted in the anterior chamber using an injector system. Group C: after CCIs were performed with 2.8, 3.0, 3.2, 3.4 mm wide slit knives, a SN 60 AT (Alcon) IOL was implanted in the anterior chamber using an injector system. CONTROL: CCIs were performed with 3.0 mm wide slit knives. Each group used five porcine eyes for each slit knife (Group A 25 eyes; Group B 25 eyes; Group C 20 eyes; CONTROL 5 eyes). The detrition of the CCIs was evaluated on three different aspects using a scanning electron microscope: a) external expansion at both edges of CCIs; b) rupture of the collagen fibers; c) expansion between the collagen fibers. Aspects a, b and c were given a score of 0, 1, and 2, respectively, and the total points were compared statistically between test and control groups. RESULTS: The degree of CCIs detrition was significantly reduced in CCIs with a width of more than 2.4 mm of CCIs width in Group A, more than 3.0 mm in Group B, and more than 3.2 mm in Group C. CONCLUSIONS: Minimizing the detrition of corneal incisions after IOL implantation needs a larger than the recommended width of corneal incision.

Comparison of the outcomes of limbal-based trabeculectomy with and without anchor sutures.

BACKGROUND AND OBJECTIVE: To retrospectively evaluate the efficacy and safety of limbal-based trabeculectomy with anchor sutures compared to standard limbal-based trabeculectomy. Limbal-based trabeculectomy was performed with a new technique using anchor sutures, which involved tying the conjunctiva to the sclera at a deep fornix incision to prevent bleb localization induced by slippage of the conjunctival suture scar toward the scleral flap. PATIENTS AND METHODS: In this retrospective, comparative, interventional case series, 45 eyes that underwent limbal-based trabeculectomy with anchor sutures and 27 eyes that underwent standard limbal-based trabeculectomy were analyzed (primary surgery). RESULTS: At a target intraocular pressure of 15 mm Hg, the 3-year survival rate using Kaplan-Meier analysis was 76.2% in the limbal-based trabeculectomy with anchor sutures group and 55.6% in the standard limbal-based trabeculectomy group. Bleb morphology analysis using the Moorfields Bleb Grading System showed that blebs in the limbal-based trabeculectomy with anchor sutures group were more diffused than those in the standard limbal-based trabeculectomy group. CONCLUSION: Limbal-based trabeculectomy with anchor sutures appears to be an effective method for decreasing intraocular pressure and improving morphology of blebs.

Preserved and unpreserved 12 anti-allergic ophthalmic solutions and ocular surface toxicity: in vitro assessment in four cultured corneal and conjunctival epithelial cell lines.

In the present study, we evaluated the cytotoxicity of anti-allergic ophthalmic solutions in cultured corneal and conjunctival cells, namely SIRC (rabbit corneal epithelium), BCE C/D-1b (bovine corneal epithelial cells), RC-1 (rabbit corneal epithelium), and Chang (human conjunctival cells). The viability of cell cultures was determined following the exposure of cells to 12 commercially available anti-allergic ophthalmic solutions for varying exposure times and at various dilutions using the MTT and neutral red assays. The cell viability score (CVS) was used to compare the toxicity of different drugs. Based on CVS data, the order of cell viability after exposure to the drugs was Zepelin ≥ Tramelas PF ≥ Cumorol PF ≥ Ketotifen PF ≥ Eyevinal = Fumarton ≥ Cumorol > Intal ≥ Rizaben ≥ Tramelas ≥ Patanol Livostin. In conclusion, cell viability was mostly affected by the concentration of benzalkonium chloride rather than the active component and/or the anti-allergic action of the drug. The CVS was useful in comparing the toxicity of different drugs.

Foldable acrylic intraocular lens with distended haptics for transscleral fixation.

We describe a foldable acrylic intraocular lens (IOL) with distended haptics suitable for transscleral fixation and the insertion procedure. The IOL has an acrylic optic and poly(methyl methacrylate) haptics with a microscopic indentation 1.3 mm from the tip. Transscleral fixation of the IOL was performed through corneal incisions in 22 eyes, and surgical results were retrospectively assessed. The IOL was sutured firmly in position using the cow-hitch procedure, and there was no suture loosening to the distended haptic. The IOL design provided suitable fixation and may be indicated for bag fixation as well as transscleral fixation.

[Cytotoxicity of antiglaucoma ophthalmic solutions for human corneal endothelial cells].

PURPOSE: The cytotoxicity of a range of commercial antiglaucoma ophthalmic solutions was assessed in human corneal endothelial cells using in vitro techniques. METHODS: Cell survival was measured using the WST-1 assay for endothelial cells and the MTT assay for epithelial cells. Commercially available timolol, carteolol, latanoplast, unoprostone, levobunolol, bunazosine, betaxolol, nipradiol, dorzolamide, brinzolamide, and pilocarpine were assessed. The survival of cells exposed to test ophthalmic solutions was expressed as a percentage of cell survival in the control solution (distilled water added to media) after 48 hours exposure. RESULTS: Survival was lower in prostagrandines and in medications containing benzalkonium. It increased to more than 85% after dilution of 1000-fold or more dilution. CONCLUSIONS: Antiglaucoma ophthalmic solutions have corneal endothelial toxicity. The toxicity significantly decreases after dilution of 1000-fold or more dilution and toxicity seems to be due mostly to benzalkonium chloride.

Cytotoxicity of ophthalmic solutions with and without preservatives to human corneal endothelial cells, epithelial cells and conjunctival epithelial cells.

PURPOSE: The cytotoxicity of a range of commercial ophthalmic solutions in the presence and absence of preservatives was assessed in human corneal endothelial cells (HCECs), corneal epithelia and conjunctival epithelia using in vitro techniques. METHODS: Cell survival was measured using the WST-1 assay for endothelial cells and the MTT assay for epithelial cells. Commercially available timolol, carteolol, cromoglicate, diclofenac, bromfenac and hyaluronic acid ophthalmic solutions were assessed for cytotoxicity in the presence and absence of preservatives. The preservatives benzalkonium, chlorobutanol and polysorbate were also tested. The survival of cells exposed to test ophthalmic solutions was expressed as a percentage of cell survival in the control solution (distilled water added to media) after 48 h exposure. RESULTS: HCEC survival was 20-30% in ophthalmic solutions diluted 10-fold. The survival of HCEC was significantly greater in all solutions in the absence of preservative than in the presence of preservative. The survival of corneal and conjunctival epithelia was consistent with that of HCECs for all test ophthalmic solutions. The preservatives polysorbate and benzalkonium were highly cytotoxic with cell survival decreasing to 20% at the concentration estimated in commercial ophthalmic solutions. By comparison, the survival of cells exposed to chlorobutanol was 80% or greater. CONCLUSIONS: The cytotoxicity of ophthalmic solutions to HCEC, corneal epithelia and conjunctival epithelia decreased in the absence of preservative.

Light scatter on the surface of AcrySof intraocular lenses: part II. Analysis of lenses following hydrolytic stability testing.

BACKGROUND AND OBJECTIVE: To investigate the surface light scatter and optical quality of AcrySof lenses (Alcon Laboratories, Inc., Fort Worth, TX) following simulated aging of 20 years. MATERIALS AND METHODS: AcrySof lenses were exposed to exaggerated thermal conditions to simulate up to 20 years of aging and were tested for surface light scatter and optical quality (modulation transfer function). RESULTS: There were no significant differences from baseline for either the surface light scatter or optical quality of the lenses over time. CONCLUSION: The current study demonstrated that surface light scatter on AcrySof lenses did not increase under conditions simulating 20 years of aging. Because the simulated aging environment contained no protein, this work indirectly supports the finding that surface light scatter is due to the deposition of a biomaterial on the lens surface rather than changes in the material. Optical performance integrity of the test lenses was maintained under severe environmental conditions.

Light scatter on the surface of AcrySof intraocular lenses: part I. Analysis of lenses retrieved from pseudophakic postmortem human eyes.

BACKGROUND AND OBJECTIVE: To investigate the cause of light scatter measured on the surface of AcrySof intraocular lenses (Alcon Laboratories, Inc., Fort Worth, TX) retrieved from pseudophakic postmortem human eyes. MATERIALS AND METHODS: Ten intraocular lenses (Alcon AcrySofModel MA60BM) were retrieved postmortem and analyzed for light scatter before and after removal of surface-bound biofilms. RESULTS: Six of the 10 lenses exhibited light scatter that was clearly above baseline levels. In these 6 lenses, both peak and average pixel density were reduced by approximately 80% after surface cleaning. CONCLUSION: The current study demonstrates that a coating deposited in vivo on the lens surface is responsible for the light scatter observed when incident light is applied.

Corneal and conjunctival toxicity of disinfectants--assessing safety for use with ophthalmic surgical instruments.

We investigated the corneal toxicity of ortho-phthalaldehyde (Cidex OPA, Johnson and Johnson K.K.) and its predecessor glutaraldehyde (Cidex, Johnson and Johnson K.K.). We made primary cultures of porcine and human corneal endothelial cells. Commercially available cell lines were also used including human, bovine, and rabbit corneal epithelium and human conjunctival cells. Following incubation for two days, cell survival was measured using a WST-1 assay for endothelia and a MTT assay for the other cells. Test solutions included 2.25% and 3.5% glutaraldehyde and 0.55% ortho-phthalaldehyde. Cell survival was presented as a percentage of the control value. ortho-phthalaldehyde displayed less toxicity than glutaraldehyde for all cell types tested. As expected 3.5% glutaraldehyde was slightly more toxic than 2.25% glutaraldehyde. When primary human corneal endothelial cultures were exposed to ortho-phthalaldehyde, the survival rates were 88% for 100-fold dilutions and 95% for 500-fold dilutions. The survival rates for all cells tested were greater than 90% when dilutions of 1000-fold or more were used. In conclusion, the corneal toxicity of glutaraldehyde and ortho-phthalaldehyde appears to be within safe levels following washing procedures and therefore the use of these disinfectants may be suitable for selected ophthalmic surgical instruments in urgent or under-equipped circumstances.

Effect of ophthalmic solution components on acrylic intraocular lenses.

PURPOSE: To investigate the effect of ophthalmic solution components on the surface of acrylic intraocular lenses (IOLs). SETTING: Department of Opthalmology, Showa University School of Medicine. METHODS: Measurement of the contact angles of ophthalmic solutions on 3 acrylic IOLs was performed. The solutions were diclofenac sodium (Diclod), bromfenac sodium (Bronuck), betamethasone phosphate (Rinderon), dibekacin sulfate (Panimycin), polysorbate 80 (Tween 20), benzalkonium chloride, chlorobutanol, methylparahydroxybenzoate, and propylparahydroxybenzoate. The IOLs were incubated at 35 degrees C for 2 weeks in undiluted ophthalmic solutions and in 1:10 dilutions of ophthalmic solution components. The IOLs were sectioned and observed by scanning electron microscopy. RESULTS: The contact angle of Diclod and Bronuck solutions was the smallest. The contact angle of Rinderon and Panimycin was similar to that of distilled water. Scanning electron microscopy examination of IOLs incubated in ophthalmic solution components showed intralenticular changes. The IOLs immersed in ophthalmic solutions did not show any change, even after extended incubation. CONCLUSION: The chemical components of ophthalmic solutions, such as surfactants and solvents, permeate acrylic IOLs, suggesting the potential for long-term adverse effects of eyedrops in pseudophakic eyes.