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Milad D, Yang Y, Eisa K, Harissi-Dagher M. Review of clinical trials addressing the Boston Keratoprosthesis. CANADIAN JOURNAL OF OPHTHALMOLOGY 2023:S0008-4182(23)00166-7. [PMID: 37253429 DOI: 10.1016/j.jcjo.2023.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 05/24/2022] [Accepted: 05/10/2023] [Indexed: 06/01/2023]
Abstract
OBJECTIVE The Boston Keratoprosthesis (KPro) has gained recognition as an alternative for patients with severe corneal disease and a poor probability of success with traditional penetrating keratoplasty. This review summarizes the knowledge clinical trials have brought to KPro and discusses ongoing trials. DESIGN Systematic review. METHODS A literature review across PubMed, Ovid MEDLINE, Cochrane CENTRAL, and ClinicalTrials.gov was performed to identify relevant published clinical trials reporting on the KPro from all years up until September 2021. All published trials were included. RESULTS There are 6 published and 6 ongoing clinical trials studying the Boston KPro. The number of patients included per trial ranged from 8 to 37. The average age of patients included per trial ranged from 39 to 62 years. Patients were followed for an average of 36.3 ± 41.8 months. Fifty percent (3 of 6) of KPro clinical trials were randomized. Indication for KPro was reported in 67% of trials (4 of 6), with primary KPro accounting for 22% of unique eyes (13 of 58) and KPro after corneal graft failure accounting for 41% of unique eyes (24 of 58), when reported. Using version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2) to assess quality and risk of bias, 50% of trials (3 of 6) had a low risk of bias, 33% (2 of 6) had some bias concerns, and 17% (1 of 6) had a high risk of bias. CONCLUSIONS There are few clinical trials published and underway on the Boston KPro, and none directly compare KPro outcomes with repeat corneal transplantation. There is a need for long-term clinical trials on the KPro to provide quality evidence for clinical decision making.
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Affiliation(s)
- Daniel Milad
- Department of Ophthalmology, University of Montreal Health Centre (CHUM), Montreal, Que
| | - Yelin Yang
- Department of Ophthalmology, University of Montreal Health Centre (CHUM), Montreal, Que
| | - Kerolos Eisa
- Department of Public Health, Queens University, Kingston, Ont
| | - Mona Harissi-Dagher
- Department of Ophthalmology, University of Montreal Health Centre (CHUM), Montreal, Que..
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Burgos-Blasco B, Vidal-Villegas B, Collado-Vincueria I, Soria-García AM, Cuiña-Sardiña R, Mendez-Fernandez R, Diaz-Valle D, Ariño-Gutierez M. Clinical outcomes of long-term corneas preserved frozen in Eusol-C used in emergency tectonic grafts. Cell Tissue Bank 2022; 24:351-356. [PMID: 36088523 PMCID: PMC9463973 DOI: 10.1007/s10561-022-10037-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 08/21/2022] [Indexed: 11/26/2022]
Abstract
To report the clinical results on the use of corneas frozen in Eusol-C as tectonic corneal grafts.Retrospective review of medical records of patients who received frozen corneas as emergency tectonic grafts from 2013 to 2020. Corneas had been stored in Eusol-C preservation media at − 78 °C for a mean time of 6.9 months. Diagnosis, transplant characteristics, microbial culture results, anatomic integrity, epithelial healing, neovascularization, transparency, infection and need for additional surgeries were registered. Fifty corneas were used in 40 patients (mean age 60.5 years, 20 males) with a median follow-up of 27.3 months after surgery. Need for tectonic graft was due to: perforation secondary to immune diseases (6, 12%), neurotrophic ulcer (11, 22%), trauma (3, 6%), corneal infection (11, 22%), chronic disorders of the ocular surface (9, 18%) and previous corneal graft failure (10, 22%). Mean size of grafts was 5.6 mm and 36 cases (72%) also received an amniotic membrane graft. Thirty-eight corneas achieved epithelization (76%), 25 (50%) were clear and 19 (38%) developed neovascularization. None of the corneas were rejected. Seventeen corneas (34%) failed: 7 (14%) due to reactivation of baseline disease and 10 (20%) due to primary graft failure. Four corneas (8%) had positive microbial cultures suggestive of contamination and 2 (4%) developed a cornea abscess non-related to a positive microbial culture. Long-term preservation of donor corneas in Eusol-C at − 78 °C is a viable technique to meet the needs of emergency grafts with minimal equipment.
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Affiliation(s)
- Barbara Burgos-Blasco
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain
- Tissue Bank, Hospital Clínico San Carlos, Madrid, Spain
| | - Beatriz Vidal-Villegas
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain.
- Tissue Bank, Hospital Clínico San Carlos, Madrid, Spain.
| | - Isabel Collado-Vincueria
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain
| | | | - Ricardo Cuiña-Sardiña
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain
| | - Rosalía Mendez-Fernandez
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain
| | - David Diaz-Valle
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain
| | - Mayte Ariño-Gutierez
- Department of Ophthalmology, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria (IdISSC), Calle Profesor Martin Lagos s/n, 28040, Madrid, Spain
- Tissue Bank, Hospital Clínico San Carlos, Madrid, Spain
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Abstract
Millions of people worldwide are bilaterally blind due to corneal diseases including infectious etiologies, trauma, and chemical injuries. While corneal transplantation can successfully restore sight in many, corneal graft survival decreases in eyes with chronic inflammation and corneal vascularization. Additionally, the availability of donor cornea material can be limited, especially in underdeveloped countries where corneal blindness may also be highly prevalent. Development of methods to create and implant an artificial cornea (keratoprosthesis)may be the only option for patients whose eye disease is not suitable for corneal transplantation or who live in regions where corneal transplantation is not possible. The Boston keratoprosthesis (B-KPro) is the most commonly implanted keratoprosthesis worldwide, having restored vision in thousands of patients. This article describes the initial design of the B-KPro and the modifications that have been made over many years. Additionally, some of the complications of surgical implantation and long-term care challenges, particularly complicating inflammation and glaucoma, are discussed. Expected final online publication date for the Annual Review of Vision Science, Volume 8 is September 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Claes Dohlman
- Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts, USA;
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Holland G, Pandit A, Sánchez-Abella L, Haiek A, Loinaz I, Dupin D, Gonzalez M, Larra E, Bidaguren A, Lagali N, Moloney EB, Ritter T. Artificial Cornea: Past, Current, and Future Directions. Front Med (Lausanne) 2021; 8:770780. [PMID: 34869489 PMCID: PMC8632951 DOI: 10.3389/fmed.2021.770780] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2021] [Accepted: 10/15/2021] [Indexed: 12/13/2022] Open
Abstract
Corneal diseases are a leading cause of blindness with an estimated 10 million patients diagnosed with bilateral corneal blindness worldwide. Corneal transplantation is highly successful in low-risk patients with corneal blindness but often fails those with high-risk indications such as recurrent or chronic inflammatory disorders, history of glaucoma and herpetic infections, and those with neovascularisation of the host bed. Moreover, the need for donor corneas greatly exceeds the supply, especially in disadvantaged countries. Therefore, artificial and bio-mimetic corneas have been investigated for patients with indications that result in keratoplasty failure. Two long-lasting keratoprostheses with different indications, the Boston type-1 keratoprostheses and osteo-odonto-keratoprostheses have been adapted to minimise complications that have arisen over time. However, both utilise either autologous tissue or an allograft cornea to increase biointegration. To step away from the need for donor material, synthetic keratoprostheses with soft skirts have been introduced to increase biointegration between the device and native tissue. The AlphaCor™, a synthetic polymer (PHEMA) hydrogel, addressed certain complications of the previous versions of keratoprostheses but resulted in stromal melting and optic deposition. Efforts are being made towards creating synthetic keratoprostheses that emulate native corneas by the inclusion of biomolecules that support enhanced biointegration of the implant while reducing stromal melting and optic deposition. The field continues to shift towards more advanced bioengineering approaches to form replacement corneas. Certain biomolecules such as collagen are being investigated to create corneal substitutes, which can be used as the basis for bio-inks in 3D corneal bioprinting. Alternatively, decellularised corneas from mammalian sources have shown potential in replicating both the corneal composition and fibril architecture. This review will discuss the limitations of keratoplasty, milestones in the history of artificial corneal development, advancements in current artificial corneas, and future possibilities in this field.
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Affiliation(s)
- Gráinne Holland
- School of Medicine, College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National University of Ireland Galway, Galway, Ireland
| | - Abhay Pandit
- CÚRAM Science Foundation Ireland Research Centre for Medical Devices, National University of Ireland, Galway, Ireland
| | - Laura Sánchez-Abella
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | - Andrea Haiek
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | - Iraida Loinaz
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | - Damien Dupin
- CIDETEC, Basque Research and Technology Alliance, Parque Científico y Tecnológico de Gipuzkoa, Donostia-San Sebastián, Spain
| | | | | | - Aritz Bidaguren
- Ophthalmology Department, Donostia University Hospital, San Sebastián, Spain
| | - Neil Lagali
- Department of Biomedical and Clinical Sciences, Faculty of Medicine, Linköping University, Linköping, Sweden
| | - Elizabeth B. Moloney
- School of Medicine, College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National University of Ireland Galway, Galway, Ireland
- CÚRAM Science Foundation Ireland Research Centre for Medical Devices, National University of Ireland, Galway, Ireland
| | - Thomas Ritter
- School of Medicine, College of Medicine, Nursing and Health Sciences, Regenerative Medicine Institute, National University of Ireland Galway, Galway, Ireland
- CÚRAM Science Foundation Ireland Research Centre for Medical Devices, National University of Ireland, Galway, Ireland
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5
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Sabeti S, Daoud R, Robert MC, Harissi-Dagher M. Frozen versus fresh corneal graft carriers in Boston keratoprosthesis surgery: 10-year outcomes. Can J Ophthalmol 2021; 57:127-133. [PMID: 33781724 DOI: 10.1016/j.jcjo.2021.02.033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/02/2021] [Accepted: 02/22/2021] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To compare 10-year clinical outcomes of frozen versus fresh corneal graft carriers for the Boston Keratoprosthesis type 1 (KPro). DESIGN Prospective, non-masked randomized controlled trial. PARTICIPANTS Nineteen eyes of 19 patients having undergone Boston KPro type 1 implantation using a fresh or frozen graft carrier. METHODS All patients that underwent Boston KPro type 1 implantation by a single experienced surgeon using an allograft carrier between October 2008 and March 2010 at the Centre Hospitalier de l'Université de Montréal were considered. Patients were excluded if they had a history of prior KPro implantation in the same eye. A subset of the patient cohort enrolled in the initial study protocol of 24 months continued follow-up to 120 months. Participants were randomized to receive either a fresh or frozen corneal graft carrier depending on tissue availability from the eye bank on the day of KPro implantation. RESULTS Nineteen eyes of 19 patients were included, with 11 in the fresh group and 8 in the frozen group. At 10 years, in the fresh and frozen groups respectively, device retention was 91% and 75%; mean best corrected visual acuity increased from counting fingers preoperatively to 20/300 and 20/125; and incidence of complications per patient was 2.36 and 2.37. There were no statistically significant differences between groups for any of these outcome measures (p > 0.05 for all analyses). CONCLUSIONS Fresh and frozen corneal graft carriers offer similar clinical outcomes for KPro implantation in terms of device retention, change in visual acuity, and rate of complications at 10 years.
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Affiliation(s)
- Saama Sabeti
- University of Ottawa Eye Institute, The Ottawa Hospital, Ottawa, Ont..
| | - Roy Daoud
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Montréal, Qué
| | - Marie-Claude Robert
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Montréal, Qué
| | - Mona Harissi-Dagher
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Montréal, Qué
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6
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Wojcik G, Ferrari S, Romano V, Ponzin D, Ahmad S, Parekh M. Corneal storage methods: considerations and impact on surgical outcomes. EXPERT REVIEW OF OPHTHALMOLOGY 2020. [DOI: 10.1080/17469899.2021.1829476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Gabriela Wojcik
- International Center for Ocular Physiopathology, Fondazione Banca degli Occhi del Veneto, Venice, Italy
| | - Stefano Ferrari
- International Center for Ocular Physiopathology, Fondazione Banca degli Occhi del Veneto, Venice, Italy
| | - Vito Romano
- St. Paul’s Eye Unit, Royal Liverpool University Hospital, Liverpool, UK
| | - Diego Ponzin
- International Center for Ocular Physiopathology, Fondazione Banca degli Occhi del Veneto, Venice, Italy
| | - Sajjad Ahmad
- Institute of Ophthalmology, University College London, London, UK
- Cornea and external eye disease, Moorfields Eye Hospital NHS Trust Foundation, London, UK
| | - Mohit Parekh
- International Center for Ocular Physiopathology, Fondazione Banca degli Occhi del Veneto, Venice, Italy
- Institute of Ophthalmology, University College London, London, UK
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Abstract
BACKGROUND Individuals who have failed one or more full thickness penetrating keratoplasties may be offered repeat corneal surgery using an artificial or donor cornea. An artificial or prosthetic cornea is known as a keratoprosthesis. Both donor and artificial corneal transplantations involve removal of the diseased and opaque recipient cornea (or the previously failed cornea) and replacement with another donor or prosthetic cornea. OBJECTIVES To assess the effectiveness of artificial versus donor corneas in individuals who have had one or more failed donor corneal transplantations. SEARCH METHODS We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2019, Issue 11); Ovid MEDLINE; Ovid Embase; LILACS (Latin American and Caribbean Health Sciences Literature database); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 4 November 2019. SELECTION CRITERIA Two review authors independently assessed reports from the electronic searches to identify randomized controlled trials or controlled clinical trials. Any discrepancies were resolved by discussion or consultation. DATA COLLECTION AND ANALYSIS We used standard methodological procedures expected by Cochrane. For discussion purposes, we summarized findings from relevant comparative case series. We performed no data synthesis. MAIN RESULTS We did not identify any randomized controlled trials or controlled clinical trials comparing artificial corneas with donor corneas for repeat corneal transplantations. AUTHORS' CONCLUSIONS The optimal management for those individuals who have failed a conventional corneal transplantation is unknown. Currently, in some centers, artificial corneal devices are routinely recommended after just one graft failure, while in other centers, they are not recommended until after multiple graft failures, or not at all. To date, there have been no controlled trials comparing the visual outcomes and complications of artificial corneal devices (particularly the Boston type 1 keratoprosthesis, which is the most commonly implanted artificial corneal device) with repeat donor corneal transplantation, in order to guide surgeons and their patients. Such a trial is needed and would offer significant benefit to an ever-increasing pool of people with visual disability due to corneal opacification, most of whom are still in productive stages of their lives.
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Affiliation(s)
- Masako Chen
- Department of Ophthalmology, Icahn School of Medicine, New York Eye and Ear Infirmary of Mount Sinai, New York, 10003, USA
| | - Sueko M Ng
- Department of Ophthalmology, School of Medicine, University of Colorado, Aurora, CO, USA
| | - Esen K Akpek
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Sumayya Ahmad
- Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
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8
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Harissi-Dagher M, Slim E. [Boston keratoprosthesis type 1]. J Fr Ophtalmol 2019; 42:295-302. [PMID: 30857801 DOI: 10.1016/j.jfo.2018.08.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 08/27/2018] [Indexed: 11/26/2022]
Abstract
Penetrating keratoplasty is the most commonly performed tissue transplant in the world. However, its success depends on the health of the ocular surface and the intact immune privilege of the eye. In the absence of these two conditions, corneal transplants have an increased failure rate and result in corneal blindness. For more than two hundred years, researchers have been trying to find the best design of the artificial cornea in order to address these cases of severe corneal blindness. Despite previous difficulties, interest in the field has recently been revived, and considerable progress has been made over the last 20 years, to the point where the keratoprosthesis is now considered a primary procedure for some indications and is no longer always a surgery of last resort. In this review, we describe the global and personal experience with Boston keratoprosthesis type 1. It is a relatively new treatment for severe corneal blindness in the context of multiple failed corneal transplants and high-risk conditions. In the last decade, changes in the design, surgical technique, and postoperative management have increased the success rate and popularity of the Boston keratoprosthesis and decreased its complications substantially, making it a safe and effective alternative for certain corneal pathologies. However, some complications persist and require management to improve the visual prognosis of patients with corneal blindness.
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Affiliation(s)
- M Harissi-Dagher
- Centre hospitalier de l'université de Montréal, département d'ophtalmologie, 1000 St-Denis, Montréal, Québec, H2X 0C1 Canada; Département ophtalmologie, centre hospitalier de l'université de Montréal, 1000 St-Denis, Montréal, Québec, H2X 0C1 Canada
| | - E Slim
- Centre hospitalier de l'université de Montréal, département d'ophtalmologie, 1000 St-Denis, Montréal, Québec, H2X 0C1 Canada; Fellow en cornée et maladies du segment antérieur de l'université de Montréal, 1000 St-Denis, Montréal, Québec, H2X 0C1 Canada.
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9
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Abstract
PURPOSE Severe corneal disease contributes significantly to the global burden of blindness. Corneal allograft surgery remains the most commonly used treatment, but does not succeed long term in every patient, and the odds of success fall with each repeated graft. The Boston keratoprosthesis type I has emerged as an alternative to repeat corneal allograft. However, cost limits its use in resource-poor settings, where most corneal blind individuals reside. METHODS All aspects of the Boston keratoprosthesis design process were examined to determine areas of potential modification and simplification, with dual goals to reduce cost and improve the cosmetic appearance of the device in situ. RESULTS Minor modifications in component design simplified keratoprosthesis manufacturing. Proportional machinist time could be further reduced by adopting a single axial length for aphakic eyes, and a single back plate diameter. The cosmetic appearance was improved by changing the shape of the back plate holes from round to radial, with a petaloid appearance, and by anodization of back plate titanium to impute a more natural color. CONCLUSIONS We have developed a modified Boston keratoprosthesis type I, which we call the "Lucia." The Lucia retains the 2 piece design and ease of assembly of the predicate device, but would allow for manufacturing at a reduced cost. Its appearance should prove more acceptable to implanted patients. Successful keratoprosthesis outcomes require daily medications for the life of the patient and rigorous, frequent, postoperative care. Effective implementation of the device in resource-poor settings will require further innovations in eye care delivery.
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Jabbour S, Harissi-Dagher M. Plugging the gap: could frozen Boston keratoprosthesis grafts end the cornea donor shortage? EXPERT REVIEW OF OPHTHALMOLOGY 2017. [DOI: 10.1080/17469899.2017.1379902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Samir Jabbour
- Ophthalmology, Centre Hospitalier de l’Université de Montréal (CHUM), Hôpital Notre-Dame, Montréal, QC, Canada
| | - Mona Harissi-Dagher
- Ophthalmology, Centre Hospitalier de l’Université de Montréal (CHUM), Hôpital Notre-Dame, Montréal, QC, Canada
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11
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Muzychuk AK, Durr GM, Shine JJ, Robert MC, Harissi-Dagher M. No Light Perception Outcomes Following Boston Keratoprosthesis Type 1 Surgery. Am J Ophthalmol 2017; 181:46-54. [PMID: 28662941 DOI: 10.1016/j.ajo.2017.06.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/14/2017] [Accepted: 06/19/2017] [Indexed: 11/29/2022]
Abstract
PURPOSE To determine the incidence rate, principal causes, and clinical course of eyes developing no light perception (NLP) visual acuity (VA) following Boston Keratoprosthesis (B-KPro) type 1 surgery. Secondary objectives include determining the incidence rate, relative risk (RR), and survival probability with respect to NLP outcomes among eyes with congenital aniridia. DESIGN Retrospective, interventional case series. SUBJECTS All patients undergoing B-KPro type 1 surgery between October 2008 and June 2016 by a single surgeon at CHUM - Hôpital Notre-Dame. METHODS Records of patients having undergone B-KPro implantation were reviewed. Eyes with a final outcome of NLP were further reviewed to determine best recorded postoperative VA, time to NLP onset, clinical course, and principal cause. Descriptive statistics, incidence rates, Kaplan-Meier survival curves, and the RR of NLP outcomes among eyes with aniridia were determined. Statistical significance was defined as P < .05. RESULTS Records of 119 patients were included, with an average follow-up of 49.1 ± 26.8 months postoperatively. Nineteen eyes had a final outcome of NLP, representing 16.0%. The incidence rate of NLP was 0.04 cases per eye-year of follow-up. The most common principal causes were inoperable retinal detachment (n = 7, 36.8%), terminal glaucoma (n = 6, 31.6%), and carrier graft melt-related complications (n = 5, 26.3%). The RR of developing NLP among eyes with aniridia was 3.04 (P = .01). CONCLUSIONS No light perception is a devastating but uncommon outcome of B-KPro surgery. Patients with aniridia seem to be at increased risk. In spite of all available medical and surgical interventions, some eyes may still suffer this outcome.
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Affiliation(s)
- Adam K Muzychuk
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec, Canada.
| | - Georges M Durr
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec, Canada
| | - Julien J Shine
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec, Canada
| | - Marie-Claude Robert
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec, Canada
| | - Mona Harissi-Dagher
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montreal, Quebec, Canada
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12
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Brunette I, Roberts CJ, Vidal F, Harissi-Dagher M, Lachaine J, Sheardown H, Durr GM, Proulx S, Griffith M. Alternatives to eye bank native tissue for corneal stromal replacement. Prog Retin Eye Res 2017; 59:97-130. [DOI: 10.1016/j.preteyeres.2017.04.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 04/15/2017] [Accepted: 04/21/2017] [Indexed: 12/13/2022]
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13
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Güell JL, Hannush S, Segovia EJ, Arrondo E, Oscar G, Gómez-Resa MV, Mateo C, Cortina S, Echevarria J, Morral M. Innovations in Management of Complications. CURRENT OPHTHALMOLOGY REPORTS 2016. [DOI: 10.1007/s40135-016-0106-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Muzychuk AK, Robert MC, Dao S, Harissi-Dagher M. Boston Keratoprosthesis Type 1: A Randomized Controlled Trial of Fresh versus Frozen Corneal Donor Carriers with Long-Term Follow-up. Ophthalmology 2016; 124:20-26. [PMID: 27566854 DOI: 10.1016/j.ophtha.2016.07.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 07/06/2016] [Accepted: 07/14/2016] [Indexed: 10/21/2022] Open
Abstract
PURPOSE To compare the long-term clinical outcomes of fresh versus frozen corneal graft carriers for the Boston Keratoprosthesis type 1 (B-KPro). DESIGN Prospective, single-center, nonblinded, randomized controlled trial. All participants were followed through the initial study protocol of 24 months and were approached to enter an extension phase, with continuing follow-up visits to 60 months. PARTICIPANTS All patients undergoing B-KPro surgery between October 2008 and December 2009 by a single experienced surgeon at the Centre Hospitalier de l'Université de Montréal using an allograft carrier were considered. Patients were excluded if they had previously undergone B-KPro implantation. METHODS Participants were randomized individually to receive a B-KPro using a frozen or a fresh corneal graft carrier on the basis of tissue availability on the day of surgery, as determined by the local eye bank. MAIN OUTCOME MEASURES The primary outcome measure was device retention at 24 and 60 months. Secondary outcome measures included surgical feasibility, visual acuity (VA), and complications. RESULTS Thirty-seven eyes of 37 patients were enrolled in the initial study protocol, with 19 eyes randomized to fresh and 18 to frozen carrier grafts. Thirty-six eyes were followed through to 24 months, with 1 lost to follow-up. Of these, 26 were enrolled in the extension (11 eyes with a frozen and 15 eyes with a fresh carrier graft). There were no differences in the baseline characteristics of patients enrolled in the extension phase versus those who were not. At 60 months, median corrected distance VA) in the fresh group had improved to 20/150 from a baseline of counting fingers, whereas the frozen group improved to 20/400 from a baseline of hand motions. Device retention was 100% at 24 months and 96% at 60 months. There were no significant differences in the rate of complications between groups. CONCLUSIONS Fresh and frozen corneal donors offer similar clinical outcomes when used as carriers for the B-KPro, with no significant differences in device retention, visual rehabilitation, or rates of complications at 24 or 60 months.
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Affiliation(s)
- Adam K Muzychuk
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montréal, Québec, Canada
| | - Marie-Claude Robert
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montréal, Québec, Canada.
| | - Stanley Dao
- Faculty of Medicine, McGill University, Montréal, Québec, Canada
| | - Mona Harissi-Dagher
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame, Montréal, Québec, Canada
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Haq Z, Cortina MS. Retroprosthetic Membrane Formation After Boston Keratoprosthesis: Is It Truly a Benign Complication? CURRENT OPHTHALMOLOGY REPORTS 2016. [DOI: 10.1007/s40135-016-0101-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Gu J, Zhai J, Zhou S, Chen J. Boston Keratoprosthesis Outcomes in Severe Ocular Chemical Burns in Southern China: A Retrospective Study. Adv Ther 2016; 33:760-73. [PMID: 27126407 DOI: 10.1007/s12325-016-0330-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION The objective of this study was to report clinical outcomes (functional and anatomic) of Boston keratoprosthesis (KPro) after severe chemical burns in Southern China. METHODS Nineteen patients (19 eyes) that sustained severe chemical injuries in Southern China were enrolled in this retrospective study in our hospital between May 2009 and June 2015. KPro implantation in these patients was performed by a single experienced surgeon (Jiaqi Chen). The parameters evaluated in this study included diagnosis, comorbidity, preoperative and postoperative visual acuity (VA), complications, KPro retention, histological and immunohistochemical results of retroprosthetic membrane (RPM) and mucous membrane over the optic cylinder. RESULTS The mean age of the patients was 42.7 ± 11.3 years (range 29-62 years). All patients were male. Of the 19 included eyes, nine had acid burns, and 10 had alkali burns. Ten patients had previously undergone failed penetrating keratoplasty. The mean follow-up time was 41.3 ± 5.5 months (range 36-56 months). Preoperatively, the VA of the patients ranged from hand movement to light perception. Postoperatively, 17 patients (89.4%) achieved at least 20/200 once, and 7 patients (36.8%) achieved at least 20/200 and maintained this acuity until the last follow-up. The initial KPro was retained in 14 (73.6%) eyes and successfully replaced in one eye. Postoperative complications included RPM in 10 eyes, glaucoma in 6 eyes, retinal detachment in 2 eyes, corneal melting in 5 eyes, ischemic optic neuropathy in 1 eye, and overgrowth of the mucous membrane over the optical cylinder in 2 eyes. The histological and immunohistochemical results of the RPM showed granulomatous disorders and mucous membrane over the optic cylinder of conjunctival origin. CONCLUSION KPro surgery can restore useful vision in patients suffering from severe chemical burns. However, postoperative VA declined with the development of complications, and ocular surface disorders caused by the chemical burns were associated with a greater incidence of KPro retention failure. The retention rate was comparable in patients using ipsilateral autologous corneal tissue with allograft corneal tissue. FUNDING Science and Technology Foundation of Guangdong Province of China, Grant Number 2014A020212714.
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Ahmad S, Mathews PM, Lindsley K, Alkharashi M, Hwang FS, Ng SM, Aldave AJ, Akpek EK. Boston Type 1 Keratoprosthesis versus Repeat Donor Keratoplasty for Corneal Graft Failure. Ophthalmology 2016; 123:165-77. [DOI: 10.1016/j.ophtha.2015.09.028] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2015] [Revised: 09/10/2015] [Accepted: 09/18/2015] [Indexed: 11/24/2022] Open
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van Essen TH, van Zijl L, Possemiers T, Mulder AA, Zwart SJ, Chou CH, Lin CC, Lai HJ, Luyten GPM, Tassignon MJ, Zakaria N, El Ghalbzouri A, Jager MJ. Biocompatibility of a fish scale-derived artificial cornea: Cytotoxicity, cellular adhesion and phenotype, and in vivo immunogenicity. Biomaterials 2015; 81:36-45. [PMID: 26717247 DOI: 10.1016/j.biomaterials.2015.11.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 11/06/2015] [Indexed: 01/30/2023]
Abstract
PURPOSE To determine whether a fish scale-derived collagen matrix (FSCM) meets the basic criteria to serve as an artificial cornea, as determined with in vitro and in vivo tests. METHODS Primary corneal epithelial and stromal cells were obtained from human donor corneas and used to examine the (in)direct cytotoxicity effects of the scaffold. Cytotoxicity was assessed by an MTT assay, while cellular proliferation, corneal cell phenotype and adhesion markers were assessed using an EdU-assay and immunofluorescence. For in vivo-testing, FSCMs were implanted subcutaneously in rats. Ologen(®) Collagen Matrices were used as controls. A second implant was implanted as an immunological challenge. The FSCM was implanted in a corneal pocket of seven New Zealand White rabbits, and compared to sham surgery. RESULTS The FSCM was used as a scaffold to grow corneal epithelial and stromal cells, and displayed no cytotoxicity to these cells. Corneal epithelial cells displayed their normal phenotypical markers (CK3/12 and E-cadherin), as well as cell-matrix adhesion molecules: integrin-α6 and β4, laminin 332, and hemi-desmosomes. Corneal stromal cells similarly expressed adhesion molecules (integrin-α6 and β1). A subcutaneous implant of the FSCM in rats did not induce inflammation or sensitization; the response was comparable to the response against the Ologen(®) Collagen Matrix. Implantation of the FSCM in a corneal stromal pocket in rabbits led to a transparent cornea, healthy epithelium, and, on histology, hardly any infiltrating immune cells. CONCLUSION The FSCM allows excellent cell growth, is not immunogenic and is well-tolerated in the cornea, and thus meets the basic criteria to serve as a scaffold to reconstitute the cornea.
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Affiliation(s)
- T H van Essen
- Department of Ophthalmology, J3-S, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
| | - L van Zijl
- Department of Research, Aeon Astron Europe B.V., J.H. Oortweg 19, 2333 CH, Leiden, The Netherlands.
| | - T Possemiers
- Department of Ophthalmology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium.
| | - A A Mulder
- Department of Molecular Cell-biology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
| | - S J Zwart
- Department of Research, Aeon Astron Europe B.V., J.H. Oortweg 19, 2333 CH, Leiden, The Netherlands.
| | - C-H Chou
- Department of Research, Body Organ Biomedical Corporation, 5F, No. 153, Section 3, Xinyi Road, Da'an District, Taipei City 106, Taiwan, ROC.
| | - C C Lin
- Department of Research, Body Organ Biomedical Corporation, 5F, No. 153, Section 3, Xinyi Road, Da'an District, Taipei City 106, Taiwan, ROC.
| | - H J Lai
- Department of Research, Aeon Astron Europe B.V., J.H. Oortweg 19, 2333 CH, Leiden, The Netherlands.
| | - G P M Luyten
- Department of Ophthalmology, J3-S, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
| | - M J Tassignon
- Department of Ophthalmology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium.
| | - N Zakaria
- Department of Ophthalmology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium; University of Antwerp, Prinsstraat 13, 2000 Antwerpen, Belgium.
| | - A El Ghalbzouri
- Department of Molecular Cell-biology, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
| | - M J Jager
- Department of Ophthalmology, J3-S, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, The Netherlands.
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Klufas MA, Yannuzzi NA, D'Amico DJ, Kiss S. Vitreoretinal aspects of permanent keratoprosthesis. Surv Ophthalmol 2015; 60:216-28. [DOI: 10.1016/j.survophthal.2014.11.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Revised: 11/01/2014] [Accepted: 11/03/2014] [Indexed: 11/17/2022]
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Boutin T, Jabbour S, Harissi-Dagher M. Improving management and outcomes of the Boston type 1 keratoprosthesis: lessons learned from available evidence. EXPERT REVIEW OF OPHTHALMOLOGY 2015. [DOI: 10.1586/17469899.2015.1023294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Al Arfaj K. Boston keratoprosthesis - Clinical outcomes with wider geographic use and expanding indications - A systematic review. Saudi J Ophthalmol 2015; 29:212-21. [PMID: 26155082 PMCID: PMC4487949 DOI: 10.1016/j.sjopt.2015.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 12/24/2014] [Accepted: 02/02/2015] [Indexed: 11/13/2022] Open
Abstract
Over 2 decades of research, several design modifications, and improvements in post-operative management have made Boston keratoprosthesis (B-KPro) a viable option for patients with corneal blindness for whom traditional keratoplasty procedure has a very low probability of success. In this systematic review, we examined the indications, visual outcomes, complications and retention rate of the literature published in the past 10 years (2005–2014). While most of the studies report smaller datasets (typically <50 eyes), some of the recent multicenter studies have reported large datasets (up to 300 eyes). Most of the literature is published from the US; however, last few years have witnessed some papers reporting the successful use of B-Kpro from developing countries or arid climatic conditions (such as the Kingdom of Saudi Arabia). Due to differences in the causes of corneal blindness in different geographic regions, newer indications for B-Kpro are emerging (e.g. trachoma). Additionally, improving clinical outcomes and increasing surgeon confidence have also expanded indications to include cases of unilateral visual impairment and paediatric age. We observed that there is growing body of evidence of successful clinical use of B-KPro; however, financial challenges, lack of trained surgeons, shortage of donor corneas must be overcome to improve accessibility of B-KPro.
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Affiliation(s)
- Khalid Al Arfaj
- Department of ophthalmology, Dammam University, Postal code 40033, King Fahad University Hospital, Alkhobar, Saudi Arabia
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Abstract
PURPOSE The aim of this study was to develop a modified ex vivo corneal cross-linking method that increases stromal resistance to enzymatic degradation for use as a carrier for the Boston keratoprosthesis. METHODS Ex vivo cross-linking of human corneas was performed using Barron artificial anterior chambers. The corneas were deepithelialized, pretreated with riboflavin solution (0.1% riboflavin/20% dextran), and irradiated with ultraviolet A (UV-A) light (λ = 370 nm, irradiance = 3 mW/cm) for various durations. The combined effect of UV-A and gamma (γ) irradiation was also assessed using the commercially available γ-irradiated corneal donors. The corneas were then trephined and incubated at 37°C with 0.3% collagenase A solution. The time to dissolution of each cornea was compared across treatments. RESULTS Deepithelialized corneas (no UV light, no riboflavin) dissolved in 5.8 ± 0.6 hours. Cross-linked corneas demonstrated increased resistance to dissolution, with a time to dissolution of 17.8 ± 2.6 hours (P < 0.0001). The corneal tissues' resistance to collagenase increased with longer UV-A exposure, reaching a plateau at 30 minutes. Cross-linking both the anterior and posterior corneas did not provide added resistance when compared with cross-linking the anterior corneas only (P > 0.05). γ-irradiated corneas dissolved as readily as deepithelialized controls regardless of whether they were further cross-linked (5.6 ± 1.2 hours) or not (6.1 ± 0.6 hours) (P = 0.43). CONCLUSIONS Collagen cross-linking of the deepithelialized anterior corneal surface for 30 minutes conferred optimal resistance to in vitro keratolysis by collagenase A.
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The Boston keratoprosthesis 2014: a step in the evolution of artificial corneas. SPEKTRUM DER AUGENHEILKUNDE 2015. [DOI: 10.1007/s00717-014-0240-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Akpek EK, Alkharashi M, Hwang FS, Ng SM, Lindsley K. Artificial corneas versus donor corneas for repeat corneal transplants. Cochrane Database Syst Rev 2014; 11:CD009561. [PMID: 25372407 PMCID: PMC4270365 DOI: 10.1002/14651858.cd009561.pub2] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND Individuals who have failed one or more full thickness penetrating keratoplasties (PKs) may be offered repeat corneal surgery using an artificial or donor cornea. An artificial or prosthetic cornea is known as a keratoprosthesis. Both donor and artificial corneal transplantations involve removal of the diseased and opaque recipient cornea (or the previously failed cornea) and replacement with another donor or prosthetic cornea. OBJECTIVES To assess the effectiveness of artificial versus donor corneas in individuals who have had one or more failed donor corneal transplantations. SEARCH METHODS We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (2013, Issue 10), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to November 2013), EMBASE (January 1980 to November 2013), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to November 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 27 November 2013. SELECTION CRITERIA Two review authors independently assessed reports from the electronic searches to identify randomized controlled trials (RCTs) or controlled clinical trials (CCTs). We resolved discrepancies by discussion or consultation with a third review author. DATA COLLECTION AND ANALYSIS For discussion purposes, we assessed findings from observational cohort studies and non-comparative case series. No data synthesis was performed. MAIN RESULTS We did not identify any RCTs or CCTs comparing artificial corneas with donor corneas for repeat corneal transplantations. AUTHORS' CONCLUSIONS The optimal management for those individuals who have failed a conventional corneal transplantation is not known. Currently, in some centers, artificial corneal devices routinely are recommended after just one graft failure, and in others, not until after multiple graft failures, or not at all. To date, there have been no controlled trials comparing the visual outcomes and complications of artificial corneal devices (particularly the Boston type 1 keratoprosthesis which is the most commonly implanted artificial corneal device) with repeat donor corneal transplantation, in order to guide surgeons and their patients. It is apparent that such a trial is needed and would offer significant benefit to an ever-increasing pool of people with visual disability due to corneal opacification, most of whom are still in productive stages of their lives.
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Affiliation(s)
- Esen K Akpek
- Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Majed Alkharashi
- Department of Ophthalmology, King Saud University, Riyadh, Saudi Arabia
| | - Frank S Hwang
- Cornea, External Disease and Refractive Surgery, Kresge Eye Institute, Detroit, Michigan, USA
| | - Sueko M Ng
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Kristina Lindsley
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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Robert MC, Arafat SN, Ciolino J. Collagen cross-linking of the Boston keratoprosthesis donor carrier to prevent corneal melting in high-risk patients. Eye Contact Lens 2014; 40:376-81. [PMID: 25320957 PMCID: PMC8487267 DOI: 10.1097/icl.0000000000000081] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To examine the clinical relevance and pathophysiology of Boston keratoprosthesis (B-KPro)-related corneal keratolysis (cornea melt) and to describe a novel method of preventing corneal melt using ex vivo crosslinked cornea tissue carrier. METHODS A review of B-KPro literature was performed to highlight cases of corneal melt. Studies examining the effect of corneal collagen cross-linking (CXL) on the biomechanical properties of corneal tissue are summarized. The use of crosslinked corneal tissue as a carrier to the B-KPro is illustrated with a case. RESULTS Corneal melting after B-KPro is a relatively rare event, occurring in 3% of eyes during the first 3 years of postoperative follow-up. The risk of post-KPro corneal melting is heightened in eyes with chronic ocular surface inflammation such as eyes with Stevens-Johnson syndrome and mucous membrane pemphigoid. This chronic inflammation results in high tear levels of matrix metalloproteinases, the enzymes responsible for collagenolysis and corneal melt. Crosslinked corneal tissue has been shown to have stiffer biomechanical properties and to be more resistant to degradation by collagenolytic enzymes. We have previously optimized the technique for ex vivo corneal CXL and are currently studying its impact on the prevention of corneal melting after B-KPro surgery in high-risk eyes. Crosslinked carrier tissue was used in a 52-year-old man with familial aniridia and severe post-KPro corneal melt. The patient maintained his visual acuity and showed no evidence of corneal thinning or melt in the first postoperative year. CONCLUSION Collagen crosslinking was previously shown to halt the enzymatic degradation of corneal buttons ex vivo. This study demonstrates the safety and potential benefit of using crosslinked corneal grafts as carriers for the B-KPro, especially in eyes at higher risk of postoperative melt.
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Affiliation(s)
- Marie-Claude Robert
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, 02114
| | - Samer N Arafat
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, 02114
| | - Joseph Ciolino
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Boston, MA, 02114
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Behlau I, Martin KV, Martin JN, Naumova EN, Cadorette JJ, Sforza JT, Pineda R, Dohlman CH. Infectious endophthalmitis in Boston keratoprosthesis: incidence and prevention. Acta Ophthalmol 2014; 92:e546-55. [PMID: 24460594 DOI: 10.1111/aos.12309] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 10/06/2013] [Indexed: 12/14/2022]
Abstract
PURPOSE To determine the cumulative worldwide incidence of infectious endophthalmitis and associated vision loss after Boston keratoprosthesis (B-KPro) Type I/II implantation and to propose both safe and inexpensive prophylactic antibiotic regimens. METHODS Two retrospective methods were used to determine the incidence, visual outcomes and aetiologies of infectious endophthalmitis associated with the B-KPro divided per decade: (i) systematic review of the literature from 1990 through January 2013 and (ii) a surveillance survey sent to all surgeons who implanted B-KPros through 2010 with 1-year minimum follow-up. In addition, a single-Boston surgeon 20-year experience was examined. RESULTS From 1990 through 2010, there were 4729 B-KPros implanted worldwide by 209 U.S. surgeons and 159 international surgeons. The endophthalmitis cumulative mean incidence declined from 12% during its first decade of use to about 3% during its second decade in the Unites States and about 5% internationally during the second decade. There remains a large incidence range both in the United States (1-12.5%) and internationally (up to 17%). Poor compliance with daily topical antibiotics is an important risk factor. While Gram-positive organisms remained dominant, fungal infections emerged during the second decade. CONCLUSIONS Daily prophylactic topical antibiotics have dramatically reduced the endophthalmitis incidence. Although Gram-positive organisms are the most common aetiology, antimicrobials must be inclusive of Gram-negative organisms. Selection of prophylactic regimens should be tailored to local antibiotic susceptibility patterns, be cost-effective, and should not promote the emergence of antimicrobial resistance. An example of a broad-spectrum, low-cost prophylactic option for non-autoimmune patients includes trimethoprim/polymyxinB once daily.
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Affiliation(s)
- Irmgard Behlau
- Ophthalmology; Massachusetts Eye and Ear Infirmary; Schepens Eye Research Institute; Harvard Medical School; Boston Massachusetts USA
- Molecular Biology & Microbiology and Ophthalmology; Tufts-Sackler Graduate School of Biomedical Sciences; Tufts University School of Medicine; Boston Massachusetts USA
- Division of Infectious Diseases; Department of Medicine; Harvard Medical School; Mount Auburn Hospital; Cambridge Massachusetts USA
- Division of Infectious Diseases; Department of Medicine; Tufts University School of Medicine; Newton-Wellesley Hospital; Newton Massachusetts USA
| | - Kathryn V. Martin
- Ophthalmology; Massachusetts Eye and Ear Infirmary; Schepens Eye Research Institute; Harvard Medical School; Boston Massachusetts USA
| | - Jacqueline N. Martin
- Ophthalmology; Massachusetts Eye and Ear Infirmary; Schepens Eye Research Institute; Harvard Medical School; Boston Massachusetts USA
| | - Elena N. Naumova
- Tufts Initiative for Forecasting and Modeling of Infectious Diseases (InForMID); School of Engineering; Tufts University; Medford Massachusetts USA
| | - James J. Cadorette
- Henry Whittier Porter Bacteriology Laboratory; Massachusetts Eye and Ear Infirmary; Boston Massachusetts USA
| | - J. Tammy Sforza
- Pharmacy Department; Massachusetts Eye and Ear Infirmary; Boston Massachusetts USA
| | - Roberto Pineda
- Ophthalmology; Massachusetts Eye and Ear Infirmary; Schepens Eye Research Institute; Harvard Medical School; Boston Massachusetts USA
| | - Claes H. Dohlman
- Ophthalmology; Massachusetts Eye and Ear Infirmary; Schepens Eye Research Institute; Harvard Medical School; Boston Massachusetts USA
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Gamma-irradiated corneas as carriers for the Boston type 1 keratoprosthesis: advantages and outcomes in a surgical mission setting. Cornea 2014; 33:235-9. [PMID: 24457451 DOI: 10.1097/ico.0000000000000065] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The Boston keratoprosthesis (KPro) is the most commonly used KPro worldwide. There are limited data on the outcomes when irradiated corneas are used as KPro carriers. We report a retrospective analysis of corneal transplantations performed in a regular surgical mission setting in Beirut, Lebanon, using the Boston KPro type 1 and gamma-irradiated carrier corneas, and we describe visual outcomes, complications, and retention percentage. METHODS We conducted a retrospective analysis of 17 consecutive eyes from 16 patients who underwent Boston KPro type 1 implantation at the Beirut Eye Specialist Hospital between December 2010 and July 2012. Patient medical records were reviewed for preoperative, intraoperative, and postoperative details. RESULTS Postoperatively, 9 (52.9%), 5 (29.4%), and 2 (11.7%) eyes had a corrected visual acuity of 20/400 or better, 20/100 or better, and 20/40 or better, respectively, at the most recent follow-up visit. A total of 16 eyes (94.1%) improved in corrected visual acuity over the course of follow-up. Overall, 13 eyes (76.4%) developed at least 1 complication after surgery. Retroprosthetic membrane formation was the most common complication, occurring in 10 eyes (58.8%). Neither infectious keratitis nor corneal stromal necrosis was noted during the follow-up period. The retention percentage was 94.1%. CONCLUSIONS The visual acuity outcomes, incidence of complications, and retention percentage of the KPro using gamma-irradiated carrier corneas are comparable with the outcomes of KPro implantation reported in the literature using fresh grafts as carriers. KPro with irradiated corneal carrier grafts seems to be an effective option to increase the supply of transplantation suitable corneas in remote areas, where fresh corneal grafts may be scarce.
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Low-cost and readily available tissue carriers for the Boston keratoprosthesis: a review of possibilities. J Ophthalmol 2013; 2013:686587. [PMID: 24371522 PMCID: PMC3859260 DOI: 10.1155/2013/686587] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/08/2013] [Indexed: 11/20/2022] Open
Abstract
The Boston keratoprosthesis (B-KPro), currently the most commonly used artificial cornea worldwide, can provide rapid visual rehabilitation for eyes with severe corneal opacities not suitable for standard corneal transplantation. However, the B-KPro presently needs a corneal graft as a tissue carrier. Although corneal allograft tissue is readily available in the United States and other developed countries with established eye banks, the worldwide need vastly exceeds supply. Therefore, a simple, safe, and inexpensive alternative to corneal allografts is desirable for the developing world. We are currently exploring reasonable alternative options such as corneal autografts, xenografts, noncorneal autologous tissues, and laboratory-made tissue constructs, as well as modifications to corneal allografts, such as deep-freezing, glycerol-dehydration, gamma irradiation, and cross-linking. These alternative tissue carriers for the B-KPro are discussed with special regard to safety, practicality, and cost for the developing world.
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Chew ACY, Mehta JS, Tan DTH. One Year of Cornea Research in Review-2012. Asia Pac J Ophthalmol (Phila) 2013; 2:401-13. [PMID: 26107152 DOI: 10.1097/apo.0000000000000022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE The purpose of this study was to provide an update of significant cornea literature published in the past 1 year. DESIGN This was a literature review. METHODS The authors conducted a 1-year English-language literature search on PubMed, from January 1, 2012, to December 31, 2012, using the following terms: corneal transplantation, anterior lamellar keratoplasty, penetrating keratoplasty, endothelial keratoplasty, Descemet stripping automated endothelial keratoplasty, Descemet membrane endothelial keratoplasty, Descemet membrane endothelial transfer, ocular surface epithelial transplantation, limbal epithelial transplantation, cultivated oral mucosal epithelial transplantation, keratoprosthesis, infectious keratitis, cross-linking, keratoconus, corneal neovascularization, corneal imaging, optical coherence tomography, Pentacam Scheimpflug imaging, and in vivo confocal microscopy. RESULTS This review includes original articles and review articles that contain significant updates and novel aspects in the field of cornea from the following journals: American Journal of Ophthalmology, British Journal of Ophthalmology, Ophthalmology, Investigative Ophthalmology and Visual Science, and Cornea. Letters to the editor, unpublished work, manuscripts not in English, and abstracts were not included. CONCLUSIONS This review highlights significant literature that is applicable to the practicing ophthalmologist.
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Affiliation(s)
- Annabel C Y Chew
- From the *Singapore National Eye Centre, †Singapore Eye Research Institute, ‡Duke-NUS Graduate Medical School, and §Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Kim MJ, Bakhtiari P, Aldave AJ. The international use of the Boston type I keratoprosthesis. Int Ophthalmol Clin 2013; 53:79-89. [PMID: 23470591 DOI: 10.1097/iio.0b013e31827ab3d3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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