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Carrothers E, Appleby M, Lai V, Kozbenko T, Alomar D, Smith BJ, Hamada N, Hinton P, Ainsbury EA, Hocking R, Yauk C, Wilkins RC, Chauhan V. AOP report: Development of an adverse outcome pathway for deposition of energy leading to cataracts. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2024. [PMID: 38644659 DOI: 10.1002/em.22594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 03/21/2024] [Indexed: 04/23/2024]
Abstract
Cataracts are one of the leading causes of blindness, with an estimated 95 million people affected worldwide. A hallmark of cataract development is lens opacification, typically associated not only with aging but also radiation exposure as encountered by interventional radiologists and astronauts during the long-term space mission. To better understand radiation-induced cataracts, the adverse outcome pathway (AOP) framework was used to structure and evaluate knowledge across biological levels of organization (e.g., macromolecular, cell, tissue, organ, organism and population). AOPs identify a sequence of key events (KEs) causally connected by key event relationships (KERs) beginning with a molecular initiating event to an adverse outcome (AO) of relevance to regulatory decision-making. To construct the cataract AO and retrieve evidence to support it, a scoping review methodology was used to filter, screen, and review studies based on the modified Bradford Hill criteria. Eight KEs were identified that were moderately supported by empirical evidence (e.g., dose-, time-, incidence-concordance) across the adjacent (directly linked) relationships using well-established endpoints. Over half of the evidence to justify the KER linkages was derived from the evidence stream of biological plausibility. Early KEs of oxidative stress and protein modifications had strong linkages to downstream KEs and could be the focus of countermeasure development. Several identified knowledge gaps and inconsistencies related to the quantitative understanding of KERs which could be the basis of future research, most notably directed to experiments in the range of low or moderate doses and dose-rates, relevant to radiation workers and other occupational exposures.
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Affiliation(s)
- Emma Carrothers
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Meghan Appleby
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Vita Lai
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Tatiana Kozbenko
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Dalya Alomar
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Benjamin J Smith
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Nobuyuki Hamada
- Biology and Environmental Chemistry Division, Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), Chiba, Japan
| | - Patricia Hinton
- Defense Research & Development Canada, Canadian Forces Environmental Medicine Establishment, Toronto, Ontario, Canada
| | - Elizabeth A Ainsbury
- Radiation, Chemical and Environmental Hazards Division, UK Health Security Agency, Birmingham, UK
- Environmental Research Group within the School of Public Health, Faculty of Medicine at Imperial College of Science, Technology and Medicine, London, UK
| | - Robyn Hocking
- Learning and Knowledge and Library Services, Health Canada, Ottawa, Ontario, Canada
| | - Carole Yauk
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Ruth C Wilkins
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Vinita Chauhan
- Consumer and Clinical Radiation Protection Bureau, Environmental and Radiation Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
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Tekin K, Ozdamar Erol Y, Inanc M, Sargon MF, Cakar Ozdal P, Berker N. Ultrastructural Analysis of the Anterior Lens Epithelium in Cataracts Associated with Uveitis. Ophthalmic Res 2019; 63:213-221. [PMID: 31838467 DOI: 10.1159/000504497] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 10/31/2019] [Indexed: 12/14/2022]
Abstract
PURPOSE To investigate the transmission electron microscopic findings of lens epithelial cells (LECs) in patients with different subtypes of uveitis and to compare the findings with those in age-matched controls. METHODS In this prospective case-control study, the anterior lens capsules were taken from 47 eyes of 47 patients with uveitis of different subtypes (17 with Fuchs uveitis syndrome [FUS], 13 with -Behçet's uveitis, 10 with idiopathic uveitis, and 7 with herpetic keratouveitis) and from 15 eyes of 15 control patients. RESULTS In the FUS group, the LECs had homogeneous thickening and irregularity, with some small vacuoles and widespread, oval-shaped pigment clusters in some areas. In the Behçet uveitis group, there was evident thinning in the lens epithelium. The subepithelial tissue under the epithelium was thickened, and edematous areas were detected. In the idiopathic uveitis group, the LECs were thinner with small vacuoles, and the cubic structure of the LECs was transformed into a squamous one. Moreover, the LECs included some small vacuoles, similar to those in the FUS group. In the herpetic keratouveitis group, two prominent cell types were observed: (1) completely normal LECs and (2) degenerated-type LECs with pyknotic nuclei, condensation of chromatin, swelling in the cytoplasm, membrane ruptures, and intra-cytoplasmic inclusion bodies. In the control group, the LECs and all of their elements occurred in normal ultrastructural patterns, with the exception of a few small intraepithelial vacuoles, which were fewer in number and smaller than those in the FUS and idiopathic uveitis groups. CONCLUSION The electron microscopic analysis of LECs of patients with different subtypes of uveitis revealed significant ultrastructural alterations, which may be related to the summation of oxidative stress and intraocular inflammation.
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Affiliation(s)
- Kemal Tekin
- Ophthalmology Department, Ercis State Hospital, Van, Turkey,
| | - Yasemin Ozdamar Erol
- Ophthalmology Department, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
| | - Merve Inanc
- Ophthalmology Department, Ercis State Hospital, Van, Turkey
| | | | - Pinar Cakar Ozdal
- Ophthalmology Department, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
| | - Nilufer Berker
- Ophthalmology Department, Ulucanlar Eye Training and Research Hospital, Ankara, Turkey
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Brash BM, Gemensky-Metzler AJ, Wilkie DA, Miller EJ, Chandler HL. Determination of trypan blue efficacy in the mitigation of ex vivo canine PCO formation. Vet Ophthalmol 2019; 22:902-909. [PMID: 30942514 DOI: 10.1111/vop.12669] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/11/2019] [Accepted: 03/16/2019] [Indexed: 12/26/2022]
Abstract
PURPOSE To determine whether trypan blue (TB) reduces canine lens epithelial cell (LEC) or corneal endothelial cell (CEC) viability in vitro; if cell death is noted, to subsequently evaluate the molecular mechanism. METHODS Cellular viability was determined using a lactate dehydrogenase (LDH) assay. In TB-treated LECs, caspase 3/7 activity was assessed to evaluate apoptosis; autophagy was evaluated using immunoblotting against LC3 and p62. To evaluate the effects of TB on ex vivo posterior capsule opacification (PCO), following mock cataract surgery, lens capsules were treated with TB and subsequently maintained in culture to determine LEC migration and proliferation. RESULTS Following acute exposure, TB did not significantly reduce LEC or CEC viability at any of the concentrations tested. Increased caspase 3/7 activity was found in LEC cultures treated with TB for an extended period of time; no change in LC3 or p62 expression was noted. Ex vivo PCO formation was not significantly altered by TB treatment. CONCLUSIONS Acute exposure to TB did not reduce LEC or CEC viability, and only longer exposure to TB was able to initiate apoptosis. Treatment with intraocular TB at the time of cataract surgery is likely safe to the CECs but will not prevent PCO formation.
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Affiliation(s)
- Breanna M Brash
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | | | - David A Wilkie
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | - Eric J Miller
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio
| | - Heather L Chandler
- College of Veterinary Medicine, The Ohio State University, Columbus, Ohio.,College of Optometry, The Ohio State University, Columbus, Ohio
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Joshi RS, Hussain MS. Long-term results of trypan blue dye irrigation in the capsular bag to prevent posterior capsule opacification: A randomized trial. Indian J Ophthalmol 2017; 65:1440-1444. [PMID: 29208831 PMCID: PMC5742979 DOI: 10.4103/ijo.ijo_454_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose: To study the effect of capsular bag irrigation of trypan blue dye (0.06%) on posterior capsular opacification (PCO) in eyes undergoing phacoemulsification. Methods: This was a randomized, trial conducted at a tertiary eye care center in central India. The study included 50 patients (100 eyes) with senile cataracts who were scheduled for phacoemulsification and intraocular lens (IOL) implantation and were willing to undergo bilateral cataract surgery. One eye of each patient was randomized to one of two groups. The dye group received 0.2 ml of trypan blue injected in the capsular bag after cortical cleanup under air. The control group (other eye of the same patient) received 0.2 ml of balanced salt solution injected in a similar manner. PCO in the central 3 mm area of IOL optic was analyzed by a masked observer using an evaluation of PCO software computer analysis system at 6, 12, 24, and 36 months. Results: The average age of patients was 62.05 ± 6.22 in the dye group and 64.92 ± 7.16 years in the control group. The mean PCO score at 6 months was significantly lower in the dye group (0.10 ± 0.15) than in the control group (0.22 ± 0.30). There were no significant differences in the PCO scores between the two groups from 12 to 36 months. At the end of 3 years, eight eyes in the dye group and seven in the control group required YAG capsulotomy (P = 0.21). Conclusion: Capsular bag irrigation of trypan blue dye decreased the PCO score at 6 months, but it had no effect at 36 months.
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Affiliation(s)
- Rajesh Subhash Joshi
- Resident, Shri Vasantrao Naik Government Medical College, Yavatmal, Maharashtra, India
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Abstract
PURPOSE To evaluate the effect of trypan blue on the elastic property of Descemet membrane (DM) by atomic force microscopy. METHODS Human corneas (n = 10) were obtained from the Illinois Eye Bank (Chicago, IL). The DM was isolated and divided into two halves, one half was stained with ophthalmic trypan blue (Vision Blue, 0.06%, DORC International), whereas the unstained other half served as control. The DM samples were then tested using the atomic force microscope. Data were analyzed using the Hertz model for the evaluation of the Young modulus of elasticity. RESULTS Atomic force microscopy showed higher cantilever deflection on trypan blue-stained DM compared with control, and the difference was statistically significant (P = 0.03). Force-distance curve analysis also revealed a statistically significant increase in the Young modulus of elasticity in the trypan blue-stained samples (10.5 ± 1.4 kPa) compared with the control (5.8 ± 0.8 kPa), (P < 0.0001). CONCLUSIONS Our results suggest that trypan blue may decrease DM elasticity and consequently increase its stiffness. This may influence the graft adherence when used for endothelial keratoplasty.
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Ari S, Caça I, Unlü K, Nergiz Y, Aksit I. Effects of trypan blue on corneal endothelium and anterior lens capsule in albino wistar rats: An investigator-masked, controlled, two-period, experimental study. Curr Ther Res Clin Exp 2014; 67:366-77. [PMID: 24678109 DOI: 10.1016/j.curtheres.2006.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2006] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND The development of continuous curvilinear capsulorrhexis (CCC) has contributed significantly to the tolerability and effectiveness of cataract extraction and intraocular lens implantation. Staining of the anterior capsule has become a popular method of increasing visibility when performing CCC. OBJECTIVE The aim of this study was to determine, using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the highest concentrations of trypan blue dye that would not cause long-term toxicity after injection into the anterior chamber of rat eyes. METHODS The eyes of healthy female albino Wistar rats were used in this investigator-masked, controlled, 2-period, experimental study conducted over 12 weeks at the Dicle University Experimental Animal Laboratory, Diyarbakir, Turkey. The rats were randomly divided into 5 groups of 4 using a random-number table. Each rat was administered a 0.05-mL injection of trypan blue into the right eye in 1 of the following concentrations: 0.4%, 0.2%, 0.1%, 0.05%, or 0.025%. A 0.05-mL pH-balanced saline solution was injected into the left eye of each rat to act as a control. At 1 day after injection and 4 weeks after injection (early period), 1 rat from each concentration group was euthanized and their eyes were enucleated. At 12 weeks after injection (late period) the remaining 2 rats from each group were euthanized and their eyes were enucleated. Corneal endothelial cells and the anterior lens capsule of the enucleated eyes were analyzed using SEM and TEM, and the results were compared with those of the control group. In the TEM analysis, the primary end point was the histopathologic changes in the cellular organelles when compared with those in the control group. In the SEM analysis, the primary end point was changes in cell shape, intracellular junctions, and density of the microvilli when compared with those in the control group. RESULTS Forty eyes from 20 albino Wistar rats (mean [SD] age, 8.2 [1.6] weeks; mean [SD] weight, 175.6 [16.5] g) were used in the study. Each group of rats received a different concentration of trypan blue in the right eye. In the early period, both the 0.4% and 0.2% concentrations were associated with the impairment of the hexagonal structure of corneal endothelial cells and intercellular junctions. Those concentrations were also associated with an increased occurrence of cellular vacuolation, cytoplasmic edema, extensive granulation of the endoplasmic reticulum, pyknotic nuclei, and mitochondrial degeneration. In the late period, these changes were observed as persisting in a decreasing manner. With the 0.1% and 0.05% concentrations, the density of microvilli decreased, nuclei appeared normal, granulation of the endoplasmic reticulum and Golgi apparatus was active, and minimal levels of mitochondrial degeneration were observed. CONCLUSIONS In this small experimental study in rat eyes, trypan blue at concentrations >0.025% was associated with impaired morphology and structure of corneal endothelial cells after short-term exposure. This effect continued in a decreasing fashion after long-term exposure. No significant changes were noted in the control group or the group administered the 0.025% concentration.
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Affiliation(s)
- Seyhmus Ari
- Department of Ophthalmology, Diyarbakir State Hospital, Diyarbakir, Turkey
| | - Ihsan Caça
- Department of Ophthalmology, Dicle University Faculty of Medicine, Diyarbakir, Turkey
| | - Kaan Unlü
- Department of Ophthalmology, Diyarbakir State Hospital, Diyarbakir, Turkey
| | - Yusuf Nergiz
- Department of Histology and Embryology, Dicle University Faculty of Medicine, Diyarbakir, Turkey
| | - Ihsan Aksit
- Technological Research and Development Center, Erciyes University, Kayseri, Turkey
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Tsaousis KT, Kopsachilis N, Tsinopoulos IT, Dimitrakos SA, Kruse FE, Welge-Luessen U. Time-dependent morphological alterations and viability of cultured human trabecular cells after exposure to Trypan blue. Clin Exp Ophthalmol 2012; 41:484-90. [DOI: 10.1111/ceo.12018] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Accepted: 10/01/2012] [Indexed: 12/01/2022]
Affiliation(s)
| | - Nikolaos Kopsachilis
- Department of Ophthalmology; Friedrich-Alexander University Erlangen-Nuremberg; Erlangen; Germany
| | - Ioannis T Tsinopoulos
- 2nd Department of Ophthalmology; Medical School; Aristotle University of Thessaloniki; Thessaloniki; Greece
| | - Stavros A Dimitrakos
- 2nd Department of Ophthalmology; Medical School; Aristotle University of Thessaloniki; Thessaloniki; Greece
| | - Friedrich E Kruse
- Department of Ophthalmology; Friedrich-Alexander University Erlangen-Nuremberg; Erlangen; Germany
| | - Ulrich Welge-Luessen
- Department of Ophthalmology; Friedrich-Alexander University Erlangen-Nuremberg; Erlangen; Germany
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Abstract
Use of vital dyes in ophthalmic surgery has gained increased importance in the past few years. Trypan blue (TB) has been a popular choice among anterior segment surgeons mainly due to its safety, ease of availability, and remarkable ability to enable an easy surgery in difficult situations mostly related to visibility of the targeted tissue. It is being used in cataract surgery since nearly a decade and its utilization has been extended to other anterior segment surgeries like trabeculectomy and corneal transplantation. This review will discuss the techniques and outcome of TB dye-assisted anterior segment surgeries.
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Trypan blue staining for capsulorhexis: ultrastructural effect on lens epithelial cells and capsules. J Cataract Refract Surg 2010; 36:582-7. [PMID: 20362849 DOI: 10.1016/j.jcrs.2009.11.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Accepted: 11/17/2009] [Indexed: 11/24/2022]
Abstract
PURPOSE To evaluate the ultrastructural effect of trypan blue 0.1% staining for capsulorhexis on lens epithelial cells (LECs) and capsules. SETTING Division of Ophthalmology, University of São Paulo, São Paulo, Brazil. METHODS Before capsulorhexis, patients were randomly assigned to 1 of 2 groups. Trypan blue 0.1% staining was performed in the treatment group. No trypan blue was used in the control group. Samples of capsules with LECs were fixed and analyzed with routine optical microscopy techniques, immunohistochemistry for beclin-1 expression (a marker of autophagy), terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling to detect apoptosis, and transmission electron microscopy (TEM). Morphometric analyses were performed, and the 2 sets of data were compared. RESULTS Each group comprised 15 patients. Cell death by autophagy and apoptosis was observed in the treatment group but not in the control group. The TEM images of subcapsular epithelium cells showed mitochondrial rupture, dilation of the cisterns of the endoplasmic reticulum, increased cytoplasmic and nuclear electron density, and abnormalities in the nuclear profile of trypan blue-stained cells. Morphometric analysis showed statistically significant differences between the 2 groups in the longest nuclear axes and the ratio between the total nuclear perimeter and the cell area (P = .03). The difference in capsule thickness between groups was not significant. CONCLUSION Trypan blue caused LEC death, which supports the hypothesis that staining with trypan blue 0.1% can help reduce the incidence of posterior capsule opacification after cataract surgery. FINANCIAL DISCLOSURE No author has a financial or proprietary interest in any material or method mentioned.
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The Use of Vital Dyes in Ocular Surgery. Surv Ophthalmol 2009; 54:576-617. [DOI: 10.1016/j.survophthal.2009.04.011] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Revised: 04/02/2009] [Accepted: 04/07/2009] [Indexed: 02/06/2023]
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Effect of trypan blue staining on the elastic modulus of anterior lens capsules of diabetic and nondiabetic patients. J Cataract Refract Surg 2009; 35:318-23. [DOI: 10.1016/j.jcrs.2008.10.040] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Revised: 10/26/2008] [Accepted: 10/30/2008] [Indexed: 11/19/2022]
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Chang YS, Hsiao JH, Tseng SH, Kuo PH, Chen FK. Indocyanine green-assisted phacoemulsification in cases of complicated or simple advanced cataracts. J Formos Med Assoc 2008; 107:710-9. [PMID: 18796361 DOI: 10.1016/s0929-6646(08)60116-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND/PURPOSE During phacoemulsification for advanced cataracts, particularly when complicated by anterior segment abnormalities, capsulorhexis is very difficult and carries a high risk of complications. This study investigated the efficacy and safety of indocyanine green (ICG)-assisted phacoemulsification in complicated or simple advanced cataracts. METHODS Thirty-two patients (35 eyes) underwent phacoemulsification for complicated advanced cataracts (group 1) or simple advanced (mature/hypermature) cataracts (group 2). Anterior segment abnormalities (corneal opacity, small pupil, or glaucoma) in group 1 complicated phacoemulsification. In both groups, 0.5% ICG was used for capsulorhexis, and subsequent procedures were performed in the same routine manner. RESULTS Group 1 included 15 patients (17 eyes) with a mean age of 60.0 years. Group 2 included 17 patients (18 eyes) with a mean age of 69.4 years (p<0.05). Continuous curvilinear capsulorhexis was completed in all eyes in group 2, but radial tears occurred in four (23.5%) eyes in group 1 (p<0.05). Phacoemulsification was performed uneventfully in all eyes in both groups. Postoperative complications (corneal edema, vitreous prolapse, posterior capsule opacity, elevated intraocular pressure) were seen in five (27.8%) eyes in group 1 and four (23.5%) eyes in group 2 (p>0.05). None of these were attributed to the use of ICG. Visual acuity improved in all eyes in group 2, but in only 11 (64.7%) in group 1 (p<0.01). CONCLUSION ICG-assisted phacoemulsification is safe and helpful for complicated or simple advanced cataracts. Differences between the two groups in patient age, intraoperative complications, and visual outcome could be explained by differences in the cause(s) of advanced cataracts.
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Affiliation(s)
- Yi-Sheng Chang
- Department of Ophthalmology and Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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Effect of trypan blue on the elasticity of the human anterior lens capsule. J Cataract Refract Surg 2008; 34:1367-73. [PMID: 18655989 DOI: 10.1016/j.jcrs.2008.03.041] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2007] [Accepted: 03/20/2008] [Indexed: 11/22/2022]
Abstract
PURPOSE To evaluate the effect of trypan blue (VisionBlue) staining on the elastic properties of the human anterior lens capsule. SETTING Center for Vision Science, Ruhr University Eye Hospital, Bochum, Germany. METHODS Nineteen anterior capsules were obtained from 19 human eyes at the time of cataract operation. Two same-size strips were prepared from each capsule; 1 was exposed to trypan blue staining for 10 seconds, and the other was a control. The elasticity measurements were performed on both specimens using a modified rheometer. RESULTS The mean age of the patients was 75.3 years +/- 13.3 (SD) (range 35 to 89 years). Sixty-three measurements of 19 suitable specimen pairs were performed. In 13 pairs, the elasticity measurements were eligible for statistical analysis. The stress value at the tearing point was statistically significantly lower in the treated group (mean 169 +/- 55 Pa) than in the control group without staining (mean 252 +/- 67 Pa) (P = .023). The difference in stress between the stained and control samples at 3 seconds and 5 seconds was not statistically significant (P = .093 versus P = .316). Dynamic frequency sweep measurements showed a statistically significant elevation of the viscosity modulus in the samples stained with trypan blue. CONCLUSIONS Trypan blue staining affected the biomechanical properties of the human lens capsule and led to a significant reduction in elasticity and an increase in stiffness. These results confirm clinical reports of changes in the capsule by dye and should be taken into consideration in dye-enhanced cataract surgery.
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Lee MY, Lee HS, Joo CK. Inadvertent Staining of the Vitreous with Trypan Blue During Cataract Surgery. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2008. [DOI: 10.3341/jkos.2008.49.7.1189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Mee Yon Lee
- Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Hyun Soo Lee
- Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Chun Ki Joo
- Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Nanavaty MA, Johar K, Sivasankaran MA, Vasavada AR, Praveen MR, Zetterström C. Effect of trypan blue staining on the density and viability of lens epithelial cells in white cataract. J Cataract Refract Surg 2006; 32:1483-8. [PMID: 16931259 DOI: 10.1016/j.jcrs.2006.04.017] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 04/03/2006] [Indexed: 11/18/2022]
Abstract
PURPOSE To assess the effect of anterior capsule staining with trypan blue 0.0125% on the density and viability of the lens epithelial cells (LECs). SETTING Iladevi Cataract and IOL Research Center, Ahmedabad, India. METHODS This randomized prospective study comprised 40 eyes having phacoemulsification for white mature cataract. Patients were randomized to have the anterior capsule stained with 0.1 mL trypan blue 0.0125% solution before the anterior capsulorhexis (Group 1, n = 20) or to have no anterior capsule staining before the anterior capsulorhexis (Group 2, n = 20). The density and viability of LECs were analyzed. The first 20 samples (10 from Group 1, 10 from Group 2) were stained with hematoxylin-eosin for cell density analysis using image-analysis software. The remaining 20 samples (10 from each group) were stained with a solution containing 0.5 microM calcein AM and 5 microM propidium iodide for 10 minutes at 37 degrees C for viability assay. RESULTS The mean cell density in Group 1 (with staining) was 3533.15 cells/mm(2) +/- 664.01 (SD). This was significantly lower than the mean of 4235.59 +/- 414.93 cells/mm(2) in Group 2 (no staining) (P = .01). The mean capsule area covered with LECs (80.75% +/- 8.04% versus 94.63% +/- 3.78%) and the mean live LECs in the covered area (51.69% +/- 11.54% versus 68.67% +/- 9.15%) were also significantly lower in Group 1 (P = .002). CONCLUSION Staining the anterior capsule with trypan blue affected the density and viability of LECs.
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Affiliation(s)
- Mayank A Nanavaty
- Iladevi Cataract & IOL Research Centre, Raghudeep Eye Clinic, Ahmedabad, India
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Jacobs DS, Cox TA, Wagoner MD, Ariyasu RG, Karp CL. Capsule Staining as an Adjunct to Cataract Surgery. Ophthalmology 2006; 113:707-13. [PMID: 16581432 DOI: 10.1016/j.ophtha.2006.01.024] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 12/12/2005] [Accepted: 01/19/2006] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE This document evaluates currently available data in the published literature to answer the question of whether the use of dye such as indocyanine green or trypan blue to stain the lens capsule to improve visualization is safe and effective as an adjunct to cataract surgery. METHODS Literature searches conducted in March 2003 and May 2004 retrieved 139 citations. The panel members reviewed the abstracts and selected 47 of possible clinical relevance for review. An additional 14 articles were identified for evaluation. Of the 61 articles reviewed, the panel members selected 36 for the panel methodologist to review and rate according to the strength of the evidence. A level I rating was assigned to properly conducted, well-designed, randomized clinical trials; a level II rating was assigned to well-designed cohort and case-control studies; and a level III rating was assigned to case series and case reports. RESULTS There is level III evidence that indocyanine green, trypan blue, and fluorescein are each effective in staining the lens capsule and that indocyanine green and trypan blue provide better ease of use and visualization of the capsule than fluoroscein. There is level II evidence that staining the capsule is helpful in completing capsulorrhexis and that it is helpful for pediatric patients under age 5 years and in cases of white cataract. The overall surgical advantage of a completed continuous curvilinear capsulorrhexis using dye has not been demonstrated, but this may be related to the outcome measures chosen rather than a failure to confer advantage. There are substantial data indicating that trypan blue 0.1% is not toxic to the cornea. There are limited data suggesting that indocyanine green 0.125% to 0.5% is not toxic to anterior segment structures. CONCLUSIONS There are data confirming that dye is safe and effective as an adjunct for capsule visualization in cataract surgery. It is reasonable to use dye when inadequate capsule visualization may compromise the outcome in cataract surgery. More studies are needed to confirm a lack of toxicity of indocyanine green and trypan blue, particularly in the event of posterior segment or longer duration exposure.
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Wong VWY, Lai TYY, Lee GKY, Lam PTH, Lam DSC. A prospective study on trypan blue capsule staining under air vs under viscoelastic. Eye (Lond) 2005; 20:820-5. [PMID: 16096664 DOI: 10.1038/sj.eye.6702032] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
AIM To compare the safety and effectiveness of trypan blue capsule staining under air vs under viscoelastic. METHODS A total of 52 consecutive patients planned for phacoemulsification of white mature cataract were randomly assigned to trypan blue staining under air or under viscoelastic. Perioperative changes in best-corrected visual acuity (BCVA), central corneal thickness (CCT), and endothelial cell density (ECD) were compared between the two groups. The differences in operating and phacoemulsification times, staining pattern, and complications between the two groups were also recorded. RESULTS Phacoemulsification of white mature cataract was performed in 50 (96%) eyes. The median preoperative BCVA was hand movement. No significant differences in the baseline characteristics were found between the two groups. At 3 months after phacoemulsification, the median BCVA improved to 0.8. The mean CCT returned to preoperative level by 1 month postoperatively and the mean ECD loss was 11.9% 3 months postoperatively. No significant differences in median BCVA, mean phacoemulsification and operation times, mean CCT, and mean ECD were found between the two groups. CONCLUSIONS Trypan blue staining of the anterior lens capsule under air or under viscoelastic were similarly effective and safe methods for the phacoemulsification of white mature cataract.
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Affiliation(s)
- V W Y Wong
- Department of Ophthalmology and Visual Science, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR
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Gouws P, Merriman M, Goethals S, Simcock PR, Greenwood RJ, Wright G. Cystoid macular oedema with trypan blue use. Br J Ophthalmol 2004; 88:1348-9. [PMID: 15377564 PMCID: PMC1772359 DOI: 10.1136/bjo.2004.041756] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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