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Glaudo M, Panfil C, Schrage NF. Defining corneal chemical burns: A novel exact and adjustable ocular model. Toxicol Rep 2021; 8:1200-1206. [PMID: 34189056 PMCID: PMC8215138 DOI: 10.1016/j.toxrep.2021.06.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 05/31/2021] [Accepted: 06/02/2021] [Indexed: 12/03/2022] Open
Abstract
Novel method induces highly reproducible chemical injuries in an ex vivo cornea model. Initial corneal surface humidity is an important parameter for consistent injury. The application frequency of the corrosive has a major impact on the extent of injury. This automated method can provide a consistent baseline for further investigations.
Introduction Live-animal-free ocular toxicity models and tests are a necessity in multiple branches of medicine, industry and science. Corneal models with adjustable ranges of injury severities do not exist. In this work, a novel and precise and dose - response method to induce and observe ex vivo corneal chemical burns has been established. Methods The EVEIT (Ex Vivo Eye Irritation Test) is based on an ex vivo corneal organ model for rabbit corneas from food industry. Further, a highly precise three – axis workstation has been employed to apply liquid corrosive, sodium hydroxide (NaOH), droplets in a nanolitre (nL) range onto the corneal surface. Optical Coherence Tomography (OCT) has been used to observe and quantify the elicited changes in the corneal layers. Results The speed and intervals of single nanodroplet application played a crucial role in the extent of the corneal changes. Similar total volumes applied at low frequencies elicited deep and extensive changes in the corneal layers whereas high application frequencies elicited comparatively superficial changes. Increasing NaOH concentrations effected measurably increasing corneal changes. Increasing the volume of applied NaOH also showed an increase in corneal changes. Conclusions OCT imaging proved to be effective in observing, documenting and quantifying the changes in the corneal layers. The ex vivo model, in conjunction with the novel application method was able to induce and display distinctive and consistent correlations between NaOH volume, concentration and elicited corneal changes. This ex vivo ocular chemical burn model provides a consistent in vitro basis for pharmaceutical and toxicological experiments and investigations into corneal chemical burn mechanisms and treatment.
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Affiliation(s)
- Markus Glaudo
- Aachen Centre of Technology Transfer in Ophthalmology, (ACTO e. V.) Karlsburgweg 9, 52070 Aachen, Germany
| | - Claudia Panfil
- Aachen Centre of Technology Transfer in Ophthalmology, (ACTO e. V.) Karlsburgweg 9, 52070 Aachen, Germany
| | - Norbert F Schrage
- Aachen Centre of Technology Transfer in Ophthalmology, (ACTO e. V.) Karlsburgweg 9, 52070 Aachen, Germany
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Bueno JM, Ávila FJ, Lorenzo-Martín E, Gallego-Muñoz P, Carmen Martínez-García M. Assessment of the corneal collagen organization after chemical burn using second harmonic generation microscopy. BIOMEDICAL OPTICS EXPRESS 2021; 12:756-765. [PMID: 33680540 PMCID: PMC7901323 DOI: 10.1364/boe.412819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 12/22/2020] [Indexed: 05/11/2023]
Abstract
The organization of the corneal stoma is modified due to different factors, including pathology, surgery or external damage. Here the changes in the organization of the corneal collagen fibers during natural healing after chemical burn are investigated using second harmonic generation (SHG) imaging. Moreover, the structure tensor (ST) was used as an objective tool for morphological analyses at different time points after burn (up to 6 months). Unlike control corneas that showed a regular distribution, the collagen pattern at 1 month of burn presented a non-organized arrangement. SHG signal levels noticeably decreased and individual fibers were hardly visible. Over time, the healing process led to a progressive re-organization of the fibers that could be quantified through the ST. At 6 months, the stroma distribution reached values similar to those of control eyes and a dominant direction of the fibers re-appeared. The present results show that SHG microscopy imaging combined with the ST method is able to objectively monitor the temporal regeneration of the corneal organization after chemical burn. Future implementations of this approach into clinically adapted devices would help to diagnose and quantify corneal changes, not only due to chemical damages, but also as a result of disease or surgical procedures.
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Affiliation(s)
- Juan M. Bueno
- Laboratorio de Óptica, Instituto Universitario de Investigación en Óptica y Nanofísica, Universidad de Murcia, Campus de Espinardo (Ed. 34), 30100 Murcia, Spain
| | | | - Elvira Lorenzo-Martín
- Dpto. Biología Celular, Histología y Farmacología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
| | - Patricia Gallego-Muñoz
- Dpto. Biología Celular, Histología y Farmacología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
| | - M. Carmen Martínez-García
- Dpto. Biología Celular, Histología y Farmacología, Facultad de Medicina, Universidad de Valladolid, 47005 Valladolid, Spain
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Lal C, Alexandrov S, Rani S, Zhou Y, Ritter T, Leahy M. Nanosensitive optical coherence tomography to assess wound healing within the cornea. BIOMEDICAL OPTICS EXPRESS 2020; 11:3407-3422. [PMID: 33014541 PMCID: PMC7510923 DOI: 10.1364/boe.389342] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/19/2020] [Accepted: 04/19/2020] [Indexed: 05/13/2023]
Abstract
Optical coherence tomography (OCT) is a non-invasive depth resolved optical imaging modality, that enables high resolution, cross-sectional imaging in biological tissues and materials at clinically relevant depths. Though OCT offers high resolution imaging, the best ultra-high-resolution OCT systems are limited to imaging structural changes with a resolution of one micron on a single B-scan within very limited depth. Nanosensitive OCT (nsOCT) is a recently developed technique that is capable of providing enhanced sensitivity of OCT to structural changes. Improving the sensitivity of OCT to detect structural changes at the nanoscale level, to a depth typical for conventional OCT, could potentially improve the diagnostic capability of OCT in medical applications. In this paper, we demonstrate the capability of nsOCT to detect structural changes deep in the rat cornea following superficial corneal injury.
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Affiliation(s)
- Cerine Lal
- Tissue Optics and Microcirculation Imaging Facility, National Biophotonics and Imaging Platform, School of Physics, National University of Ireland, Galway, Ireland
| | - Sergey Alexandrov
- Tissue Optics and Microcirculation Imaging Facility, National Biophotonics and Imaging Platform, School of Physics, National University of Ireland, Galway, Ireland
| | - Sweta Rani
- Regenerative Medicine Institute, National University of Ireland, Galway, Ireland
| | - Yi Zhou
- Tissue Optics and Microcirculation Imaging Facility, National Biophotonics and Imaging Platform, School of Physics, National University of Ireland, Galway, Ireland
| | - Thomas Ritter
- Regenerative Medicine Institute, National University of Ireland, Galway, Ireland
| | - Martin Leahy
- Tissue Optics and Microcirculation Imaging Facility, National Biophotonics and Imaging Platform, School of Physics, National University of Ireland, Galway, Ireland
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Lewis CJ, Hodgkinson EL, Allison KP. Corrosive attacks in the UK - Psychosocial perspectives and decontamination strategies. Burns 2019; 46:213-218. [PMID: 31784238 DOI: 10.1016/j.burns.2019.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 05/28/2019] [Accepted: 06/04/2019] [Indexed: 10/25/2022]
Abstract
Acid attacks, or vitriolage, are defined as violent assaults involving the deliberate throwing of an acid or similarly corrosive substance with the intention to "maim, disfigure, torture or kill" [1]. The Acid Survivors Trust International suggest a prevalence of 1500 attacks reported worldwide per annum, although this is likely to be an underestimate by 40% [2]. The UK is thought to have one of the highest of rates of recorded corrosive attacks, with an increase from 228 attacks in 2012 to 601 in 2016. Most were reported by the London Metropolitan police force followed by Northumbria, Cambridgeshire, Hertfordshire, Greater Manchester and Humberside [[2]]. The chemical agents involved include acids, alkalis, oxidising and reducing agents, alkylating and chelating agents and solvents. They cause injury by producing a chemical interaction which can lead to extensive tissue destruction and extreme pain. Herein, we present a review on the changing epidemiology of corrosive attacks in the UK and currently employed management strategies.
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Affiliation(s)
- C J Lewis
- Department of Plastic Surgery, James Cook University Hospital, Middlesbrough, UK.
| | - E L Hodgkinson
- Psychology in Healthcare, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | - K P Allison
- Department of Plastic Surgery, James Cook University Hospital, Middlesbrough, UK
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Bizrah M, Yusuf A, Ahmad S. An update on chemical eye burns. Eye (Lond) 2019; 33:1362-1377. [PMID: 31086244 PMCID: PMC7002428 DOI: 10.1038/s41433-019-0456-5] [Citation(s) in RCA: 79] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 02/06/2019] [Accepted: 04/02/2019] [Indexed: 01/20/2023] Open
Abstract
Ocular chemical injuries vary in severity, with the more severe end of the spectrum having profound visual consequences and medicolegal implications. Grading of ocular injuries is critical for determining acute treatment and visual prognosis. Poor immediate management results in more challenging treatment of acute disease. Similarly, poorly controlled acute disease results in more treatment-resistant chronic ocular disease. Despite several decades of research and public health initiatives, simple and effective interventions such as wearing protective eyewear and immediate irrigation of eyes remain as key challenges. Education and prevention are therefore important public health messages. Hurdles in the acute management of disease include poor evidence-base for commonly used treatments (e.g. based on experimental animal studies), reduced treatment adherence rates and high clinic non-attendance rates. The evolution of treatment strategies, particularly limbal stem cell transplantation, has revolutionised the visual and cosmetic outcomes in chronic phases of disease. It is therefore increasingly important to consider tertiary referral for patients with limbal stem cell failure or vision-limiting corneal scarring.
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Affiliation(s)
- Mukhtar Bizrah
- Imperial College Healthcare NHS Trust, Western Eye Hospital, 153-173 Marylebone Road, London, NW1 5QH, UK.
| | - Ammar Yusuf
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL, UK
| | - Sajjad Ahmad
- Moorfields Eye Hospital NHS Foundation Trust, 162 City Road, London, EC1V 2PD, UK
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Delafontaine M, Panfil C, Spöler F, Kray S, Burgher F, Mathieu L, Blomet J, Schrage NF, Tambourgi DV. The Ex vivo Eye Irritation Test (EVEIT) model as a mean of improving venom ophthalmia understanding. Toxicon 2018; 150:253-260. [PMID: 29890230 DOI: 10.1016/j.toxicon.2018.06.061] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 05/12/2018] [Accepted: 06/07/2018] [Indexed: 11/15/2022]
Abstract
Snakes belonging to the genus Naja (Elapid family), also known as "spitting cobras", can spit venom towards the eyes of the predator as a defensive strategy, causing painful and potentially blinding ocular envenoming. Venom ophthalmia is characterized by pain, hyperemia, blepharitis, blepharospasm and corneal erosions. Elapid venom ophthalmia is not well documented and no specific treatment exists. Furthermore, accidental ejection of venom by non-spitting vipers, as Bothrops, also occurs. The Ex vivo Eye Irritation Test model (EVEIT) has enabled important progress in the knowledge of chemical ocular burns. Considering the lack of experimental animal model, we adapted the EVEIT to study venom ophthalmia mechanisms. Ex vivo rabbit corneas were exposed to venoms from spitting (Naja mossambica, Naja nigricollis) and non-spitting (Naja naja, Bothrops jararaca and Bothrops lanceolatus) snakes, and rinsed or not with water. The corneal thickness and the depth of damage were assessed using high-resolution optical coherence tomography (HR-OCT) imaging and histological analysis. All Naja venoms induced significant corneal edema, collagen structure disorganization and epithelial necrosis. Corneas envenomed by African N. mossambica and N. nigricollis venoms were completely opaque. Opacification was not observed in corneas treated with venoms from non-spitting snakes, such as the Asian cobra, N. naja, and the vipers, B. jararaca and B. lanceolatus. Moreover, Bothrops venoms were able to damage the epithelium and cause collagen structure disorganization, but not edema. Immediate water rinsing improved corneal status, though damage and edema could still be observed. In conclusion, the present study shows that the EVEIT model was successfully adapted to set a new experimental ex vivo animal model of ophthalmia, caused by snake venoms, which will enable to explore new therapies for venom ophthalmia.
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Affiliation(s)
- Marie Delafontaine
- Prevor Laboratory, Valmondois, France; Immunochemistry Laboratory, Butantan Institute, São Paulo, Brazil
| | - Claudia Panfil
- Aachen Centre of Technology Transfer in Ophthalmology, Aachen, Germany
| | - Felix Spöler
- Institute of Semiconductor Electronics, RWTH Aachen University, Germany
| | - Stefan Kray
- Institute of Semiconductor Electronics, RWTH Aachen University, Germany
| | | | | | | | - Norbert F Schrage
- Aachen Centre of Technology Transfer in Ophthalmology, Aachen, Germany
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Lewis C, Al-Mousawi A, Jha A, Allison K. Is it time for a change in the approach to chemical burns? The role of Diphoterine ® in the management of cutaneous and ocular chemical injuries. J Plast Reconstr Aesthet Surg 2017; 70:563-567. [DOI: 10.1016/j.bjps.2017.02.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Revised: 02/09/2017] [Accepted: 02/17/2017] [Indexed: 11/29/2022]
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Cosmetics Europe compilation of historical serious eye damage/eye irritation in vivo data analysed by drivers of classification to support the selection of chemicals for development and evaluation of alternative methods/strategies: the Draize eye test Reference Database (DRD). Arch Toxicol 2016; 91:521-547. [PMID: 26997338 PMCID: PMC5306081 DOI: 10.1007/s00204-016-1679-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 02/09/2016] [Indexed: 10/28/2022]
Abstract
A thorough understanding of which of the effects assessed in the in vivo Draize eye test are responsible for driving UN GHS/EU CLP classification is critical for an adequate selection of chemicals to be used in the development and/or evaluation of alternative methods/strategies and for properly assessing their predictive capacity and limitations. For this reason, Cosmetics Europe has compiled a database of Draize data (Draize eye test Reference Database, DRD) from external lists that were created to support past validation activities. This database contains 681 independent in vivo studies on 634 individual chemicals representing a wide range of chemical classes. A description of all the ocular effects observed in vivo, i.e. degree of severity and persistence of corneal opacity (CO), iritis, and/or conjunctiva effects, was added for each individual study in the database, and the studies were categorised according to their UN GHS/EU CLP classification and the main effect driving the classification. An evaluation of the various in vivo drivers of classification compiled in the database was performed to establish which of these are most important from a regulatory point of view. These analyses established that the most important drivers for Cat 1 Classification are (1) CO mean ≥ 3 (days 1-3) (severity) and (2) CO persistence on day 21 in the absence of severity, and those for Cat 2 classification are (3) CO mean ≥ 1 and (4) conjunctival redness mean ≥ 2. Moreover, it is shown that all classifiable effects (including persistence and CO = 4) should be present in ≥60 % of the animals to drive a classification. As a consequence, our analyses suggest the need for a critical revision of the UN GHS/EU CLP decision criteria for the Cat 1 classification of chemicals. Finally, a number of key criteria are identified that should be taken into consideration when selecting reference chemicals for the development, evaluation and/or validation of alternative methods and/or strategies for serious eye damage/eye irritation testing. Most important, the DRD is an invaluable tool for any future activity involving the selection of reference chemicals.
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Spöler F, Kray O, Kray S, Panfil C, Schrage NF. The Ex Vivo Eye Irritation Test as an Alternative Test Method for Serious Eye Damage/Eye Irritation. Altern Lab Anim 2015; 43:163-79. [DOI: 10.1177/026119291504300306] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Ocular irritation testing is a common requirement for the classification, labelling and packaging of chemicals (substances and mixtures). The in vivo Draize rabbit eye test (OECD Test Guideline 405) is considered to be the regulatory reference method for the classification of chemicals according to their potential to induce eye injury. In the Draize test, chemicals are applied to rabbit eyes in vivo, and changes are monitored over time. If no damage is observed, the chemical is not categorised. Otherwise, the classification depends on the severity and reversibility of the damage. Alternative test methods have to be designed to match the classifications from the in vivo reference method. However, observation of damage reversibility is usually not possible in vitro. Within the present study, a new organotypic method based on rabbit corneas obtained from food production is demonstrated to close this gap. The Ex Vivo Eye Irritation Test (EVEIT) retains the full biochemical activity of the corneal epithelium, epithelial stem cells and endothelium. This permits the in-depth analysis of ocular chemical trauma beyond that achievable by using established in vitro methods. In particular, the EVEIT is the first test to permit the direct monitoring of recovery of all corneal layers after damage. To develop a prediction model for the EVEIT that is comparable to the GHS system, 37 reference chemicals were analysed. The experimental data were used to derive a three-level potency ranking of eye irritation and corrosion that best fits the GHS categorisation. In vivo data available in the literature were used for comparison. When compared with GHS classification predictions, the overall accuracy of the three-level potency ranking was 78%. The classification of chemicals as irritating versus non-irritating resulted in 96% sensitivity, 91% specificity and 95% accuracy.
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Affiliation(s)
- Felix Spöler
- Institute of Semiconductor Electronics, RWTH Aachen University, Aachen, Germany
| | - Oya Kray
- Institute of Semiconductor Electronics, RWTH Aachen University, Aachen, Germany
- Aachen Centre for Technology Transfer in Ophthalmology, Aachen, Germany
| | - Stefan Kray
- Institute of Semiconductor Electronics, RWTH Aachen University, Aachen, Germany
| | - Claudia Panfil
- Institute of Semiconductor Electronics, RWTH Aachen University, Aachen, Germany
- Aachen Centre for Technology Transfer in Ophthalmology, Aachen, Germany
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Retrospective analysis of the Draize test for serious eye damage/eye irritation: importance of understanding the in vivo endpoints under UN GHS/EU CLP for the development and evaluation of in vitro test methods. Arch Toxicol 2013; 88:701-23. [PMID: 24374802 PMCID: PMC3927066 DOI: 10.1007/s00204-013-1156-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 10/29/2013] [Indexed: 11/14/2022]
Abstract
For more than two decades, scientists have been trying to replace the regulatory in vivo Draize eye test by in vitro methods, but so far only partial replacement has been achieved. In order to better understand the reasons for this, historical in vivo rabbit data were analysed in detail and resampled with the purpose of (1) revealing which of the in vivo endpoints are most important in driving United Nations Globally Harmonized System/European Union Regulation on Classification, Labelling and Packaging (UN GHS/EU CLP) classification for serious eye damage/eye irritation and (2) evaluating the method’s within-test variability for proposing acceptable and justifiable target values of sensitivity and specificity for alternative methods and their combinations in testing strategies. Among the Cat 1 chemicals evaluated, 36–65 % (depending on the database) were classified based only on persistence of effects, with the remaining being classified mostly based on severe corneal effects. Iritis was found to rarely drive the classification (<4 % of both Cat 1 and Cat 2 chemicals). The two most important endpoints driving Cat 2 classification are conjunctiva redness (75–81 %) and corneal opacity (54–75 %). The resampling analyses demonstrated an overall probability of at least 11 % that chemicals classified as Cat 1 by the Draize eye test could be equally identified as Cat 2 and of about 12 % for Cat 2 chemicals to be equally identified as No Cat. On the other hand, the over-classification error for No Cat and Cat 2 was negligible (<1 %), which strongly suggests a high over-predictive power of the Draize eye test. Moreover, our analyses of the classification drivers suggest a critical revision of the UN GHS/EU CLP decision criteria for the classification of chemicals based on Draize eye test data, in particular Cat 1 based only on persistence of conjunctiva effects or corneal opacity scores of 4. In order to successfully replace the regulatory in vivo Draize eye test, it will be important to recognise these uncertainties and to have in vitro tools to address the most important in vivo endpoints identified in this paper.
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Crane AM, Hua HU, Coggin AD, Gugiu BG, Lam BL, Bhattacharya SK. Mass spectrometric analyses of phosphatidylcholines in alkali-exposed corneal tissue. Invest Ophthalmol Vis Sci 2012; 53:7122-30. [PMID: 22956606 DOI: 10.1167/iovs.12-10448] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE The aims were to determine whether exposure to sodium hydroxide results in predictable changes in phosphatidylcholine (PC) in corneal tissue and if PC profile changes correlate to exposure duration. PCs are major components of the cell membrane lipid bilayer and are often involved in biological processes such as signaling. METHODS Enucleated porcine (n = 140) and cadaver human eyes (n = 20) were exposed to water (control) and 11 M NaOH. The corneas were excised and lipids were extracted using the Bligh and Dyer method with suitable modifications. Class-specific lipid identification was carried out using a ratiometric lipid standard on a TSQ Quantum Access Max mass spectrometer. Protein amounts were determined using Bradford assays. RESULTS Control and alkali-treated corneas showed reproducible PC spectra for both porcine and human corneas. Over 200 PCs were identified for human and porcine control and each experimental time point. Several PC species (m/z values) consequent upon alkali exposure could not be ascribed to a recorded PC species. Control and treated groups showed 41 and 29 common species among them for porcine and human corneas, respectively. The unique PC species peaked at 12 minutes and at 30 minutes for human and porcine corneas followed by a decline consistent with an interplay of alkali penetration and hydrolyses at various time points. CONCLUSIONS Alkali exposure dramatically changes the PC profile of cornea. Our data are consistent with penetration and hydrolysis as stochastic contributors to changes in PCs due to exposure to alkali for a finite duration and amount.
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Affiliation(s)
- Ashley M Crane
- Bascom Palmer Eye Institute, University of Miami, Miami, Florida, USA
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Abstract
Chemical burns of the eye are becoming rare due to improvements in occupational protection. Effective decontamination is the foundation for good clinical results of this ophthalmological emergency. The toxicological aspect focuses on classifying the specific toxicity of a chemical substance by evaluating the degree of eye irritation and eye burns. Chemical substances are classified into defined risk levels by specific tests. The traditional ophthalmological approach is based on the clinical presentation of eye burns as a result of contact with a specific toxic substance. In an integral approach it is shown that substance-specific characteristics, such as concentration and specific reactivity as well as individual features, such as mode and duration of exposition have an influence on the clinical appearance of the tissue damage. The decontamination is dependent on the mode of action and the effectiveness of the decontamination solution. Amphoteric substances have the best effectiveness for decontamination of the eye due to their specific characteristics.
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