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Matthyssen S, Van den Bogerd B, Dhubhghaill SN, Koppen C, Zakaria N. Corneal regeneration: A review of stromal replacements. Acta Biomater 2018; 69:31-41. [PMID: 29374600 DOI: 10.1016/j.actbio.2018.01.023] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/16/2018] [Accepted: 01/16/2018] [Indexed: 12/13/2022]
Abstract
Corneal blindness is traditionally treated by transplantation of a donor cornea, or in severe cases by implantation of an artificial cornea or keratoprosthesis. Due to severe donor shortages and the risks of complications that come with artificial corneas, tissue engineering in ophthalmology has become more focused on regenerative strategies using biocompatible materials either with or without cells. The stroma makes up the bulk of the corneal thickness and mainly consists of a tightly interwoven network of collagen type I, making it notoriously difficult to recreate in a laboratory setting. Despite the challenges that come with corneal stromal tissue engineering, there has recently been enormous progress in this field. A large number of research groups are working towards developing the ideal biomimetic, cytocompatible and transplantable stromal replacement. Here we provide an overview of the approaches directed towards tissue engineering the corneal stroma, from classical collagen gels, films and sponges to less traditional components such as silk, fish scales, gelatin and polymers. The perfect stromal replacement has yet to be identified and future research should be directed at combined approaches, in order to not only host native stromal cells but also restore functionality. STATEMENT OF SIGNIFICANCE In the field of tissue engineering and regenerative medicine in ophthalmology the focus has shifted towards a common goal: to restore the corneal stroma and thereby provide a new treatment option for patients who are currently blind due to corneal opacification. Currently the waiting lists for corneal transplantation include more than 10 million patients, due to severe donor shortages. Alternatives to the transplantation of a donor cornea include the use of artificial cornea, but these are by no means biomimetic and therefore do not provide good outcomes. In recent years a lot of work has gone into the development of tissue engineered scaffolds and other biomaterials suitable to replace the native stromal tissue. Looking at all the different approaches separately is a daunting task and up until now there was no review article in which every approach is discussed. This review does include all approaches, from classical tissue engineering with collagen to the use of various alternative biomaterials and even fish scales. Therefore, this review can serve as a reference work for those starting in the field and but also to stimulate collaborative efforts in the future.
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Gibbons A, Leung EH, Haddock LJ, Medina CA, Fernandez V, Parel JMA, Durkee HA, Amescua G, Alfonso EC, Perez VL. Long-term outcomes of the aphakic snap-on Boston type I keratoprosthesis at the Bascom Palmer Eye Institute. Clin Ophthalmol 2018; 12:331-337. [PMID: 29497273 PMCID: PMC5818861 DOI: 10.2147/opth.s144403] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose To determine the indications, long-term clinical and visual outcomes, and complications of the aphakic snap-on type I Boston keratoprosthesis (KPro). Design Retrospective, non-comparative case series. Methods Forty-five eyes of 43 patients with type I aphakic snap-on KPros with at least 1 year of follow-up were included. The past medical histories, preoperative indications, best-corrected visual acuities (BCVAs), postoperative complications, and retention rates were analyzed. Results The most common indication for KPro implantation was a failed corneal graft (89%). The mean preoperative BCVA was count fingers–hand motion (2.14±0.45 logarithm of minimum angle of resolution [logMAR]), which initially improved to 20/200 (1.04±0.85 logMAR; P<0.0001). At the last examination, 24 eyes (53%) maintained some visual gain, 22% retained their preoperative visual acuity, and 24% lost vision due to postoperative events and underlying ocular comorbidities. Postoperative complications included retroprosthetic membranes (8/45, 18%), corneal melts (5/45, 11%), glaucoma progression (6/45, 13%), and endophthalmitis or sterile vitritis (6/45, 13%). The KPro retention rate was 89%, with a mean follow-up of 51 months. The mean BCVA at the last visit was 20/1,400 (1.82±0.92 logMAR). Conclusion Most patients experienced improved visual acuity after the implantation of the aphakic, snap-on type I KPro; however, the visual gains were not sustained over time, correlating with the onset of postoperative complications.
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Affiliation(s)
- Allister Gibbons
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL
| | - Ella H Leung
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL
| | - Luis J Haddock
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL
| | - Carlos A Medina
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL
| | - Viviana Fernandez
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
| | - Jean-Marie A Parel
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL.,Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
| | - Heather A Durkee
- Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL
| | - Guillermo Amescua
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL
| | - Eduardo C Alfonso
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL
| | - Victor L Perez
- Bascom Palmer Eye Institute/University of Miami Miller School of Medicine, Miami, FL.,Ocular Surface Center, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
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Boston keratoprosthesis type 1: outcomes of the first 38 cases performed at Moorfields Eye Hospital. Eye (Lond) 2018; 32:1087-1092. [PMID: 29440740 DOI: 10.1038/s41433-018-0016-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 09/14/2017] [Accepted: 12/20/2017] [Indexed: 11/08/2022] Open
Abstract
PURPOSE To evaluate outcomes of Boston keratoprosthesis type 1 (K-Pro) surgery in a cohort of high-risk patients at Moorfields Eye Hospital. Our patients were referred to us at the end-point of their ocular disease. METHODS A retrospective review of all K-Pro surgery performed between March 2011 and July 2015 with a minimum follow-up of 12 months. RESULTS 39 eyes of 38 patients were included. Mean follow-up was 28.4 months (range: 12-56). The main indication for surgery was bullous keratopathy from multiple failed grafts (56%). 26 cases (72.2%) had known posterior segment disease pre-operatively. Mean BCVA for the entire cohort (n = 39) initially improved from HM vision to 1/60 before returning to CF vision by 6 months and was maintained for the duration of follow-up. By final follow-up (n = 39), 46% had improved vision (1 line improvement in 10%; 2 lines or more in 36%) and 31% maintained pre-operative visual acuity. Anterior segment pathology was not an independent variable in visual outcome. However, absence of posterior segment disease was significant and performed best, improving from HM to 6/15 and maintaining that vision in the longer term. There were 13 (33%) cases of progressive glaucomatous optic neuropathy, 10 (26%) retinal detachments, 8 (21%) retroprosthetic membranes, 3 (8%) infective keratitis and 2 (5%) vitritis of which 1 progressed to endophthalmitis. In all, 3 (8%) had NPL vision and 4 (10%) required removal of the K-Pro. CONCLUSIONS Implantation of the Boston K-Pro can lead to improved vision, with the main limiting factor being posterior segment pathology.
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Kang KB, Karas FI, Rai R, Hallak JA, Kang JJ, de la Cruz J, Cortina MS. Five year outcomes of Boston type I keratoprosthesis as primary versus secondary penetrating corneal procedure in a matched case control study. PLoS One 2018; 13:e0192381. [PMID: 29408907 PMCID: PMC5800684 DOI: 10.1371/journal.pone.0192381] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Accepted: 01/20/2018] [Indexed: 11/19/2022] Open
Abstract
Despite improved retention and reduced complication rates paving the way for the current expansion of applications and surge in prevalence for the Boston type I Keratoprosthesis (KPro), the most frequent indication for its implantation today remains prior graft failure. The purpose of this study is to evaluate the long-term outcomes of primary KPro and compare to secondary implantation in a matched cohort study. This study included patients who underwent KPro implantation in a single center by two surgeons between July 2008 and October 2014. All eyes with KPro implantation as the primary procedure with a minimum follow up of 12 months were matched with eyes with same preoperative diagnoses that underwent secondary KPro implantation. Main outcomes included visual acuity and device retention. A total of 56 eyes were included with 28 eyes in each group. Mean follow up was 5.0 years for both groups. Twenty-nine percent (8) of the eyes in the primary group had a diagnosis of chemical or thermal injuries, 25% (7) aniridia, 18% (5) autoimmune disease, 4% (1) infectious keratitis/neurotrophic cornea, 7% (2) gelatinous corneal dystrophy, 7% (2) ectrodactyly ectodermal dysplasia/limbal stem cell deficiency, and 11% (3) uveitis/hypotony. Sixty-one percent (17) of the eyes in the primary group and 39% (11) in the secondary group maintained a final best-corrected visual acuity of 20/200 or better at a mean follow up of 5.0 years; the probability of maintaining best-corrected vision is 0.83 and 0.49 for primary and secondary groups at 5.0 years (p = 0.02). There is no statistically significant difference between groups in device retention (p = 0.22) or postoperative complication rates (p >0.05). This study demonstrates that Boston KPro implantation may be successful as a primary procedure in patients at high risk of failure with traditional penetrating keratoplasty. The device has a good long-term retention rate and visual outcomes are promising however a larger study is needed for more definitive results.
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Affiliation(s)
- Kai B. Kang
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Faris I. Karas
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Ruju Rai
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Joelle A. Hallak
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Joann J. Kang
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Jose de la Cruz
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
| | - Maria S. Cortina
- Illinois Eye and Ear Infirmary, Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, IL, United States of America
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Tidu A, Ghoubay-Benallaoua D, Teulon C, Asnacios S, Grieve K, Portier F, Schanne-Klein MC, Borderie V, Mosser G. Highly concentrated collagen solutions leading to transparent scaffolds of controlled three-dimensional organizations for corneal epithelial cell colonization. Biomater Sci 2018; 6:1492-1502. [DOI: 10.1039/c7bm01163f] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Controlling both organizations and transparency of dense collagen scaffolds.
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Affiliation(s)
- Aurélien Tidu
- Sorbonne Université
- CNRS
- Collège de France
- Laboratoire Chimie de la Matière Condensée de Paris
- LCMCP
| | - Djida Ghoubay-Benallaoua
- Sorbonne Université
- Institut de la Vision
- INSERM
- CNRS
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts
| | - Claire Teulon
- Laboratory for Optics and Biosciences
- LOB
- Ecole Polytechnique
- CNRS
- Inserm
| | - Sophie Asnacios
- Sorbonne Université
- CNRS
- Univ Paris Diderot
- Laboratoire Matière et Systèmes Complexes
- MSC
| | - Kate Grieve
- Sorbonne Université
- Institut de la Vision
- INSERM
- CNRS
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts
| | - François Portier
- Sorbonne Université
- CNRS
- Collège de France
- Laboratoire Chimie de la Matière Condensée de Paris
- LCMCP
| | | | - Vincent Borderie
- Sorbonne Université
- Institut de la Vision
- INSERM
- CNRS
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts
| | - Gervaise Mosser
- Sorbonne Université
- CNRS
- Collège de France
- Laboratoire Chimie de la Matière Condensée de Paris
- LCMCP
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Gologorsky D, Williams BK, Flynn HW. Posterior Pole Retinal Detachment Due to a Macular Hole in a Patient with a Boston Keratoprosthesis. Am J Ophthalmol Case Rep 2017; 5:56-58. [PMID: 28944307 PMCID: PMC5607640 DOI: 10.1016/j.ajoc.2016.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
PURPOSE To describe the clinical course of a patient with a Boston Keratoprosthesis type I who developed a localized posterior pole retinal detachment secondary to a macular hole. OBSERVATIONS A 73-year-old patient with a Boston Keratoprosthesis developed a localized posterior pole retinal detachment secondary to a macular hole. The retinal detachment was repaired with a 23-gauge pars plana vitrectomy, membrane peel, fluid-air exchange and 18% C3F8. Retinal reattachment was achieved but the macular hole remained open. CONCLUSIONS AND IMPORTANCE A posterior pole retinal detachment secondary to a macular hole can be repaired using standard techniques despite the limited view through a Boston Keratoprosthesis.
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Affiliation(s)
- Daniel Gologorsky
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Basil K Williams
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Harry W Flynn
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL, USA
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Glaucoma after corneal replacement. Surv Ophthalmol 2017; 63:135-148. [PMID: 28923582 DOI: 10.1016/j.survophthal.2017.09.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/08/2017] [Accepted: 09/11/2017] [Indexed: 01/18/2023]
Abstract
Glaucoma is a well-known complication after corneal transplantation surgery. Traditional corneal transplantation surgery, specifically penetrating keratoplasty, has been slowly replaced by the advent of new corneal transplantation procedures: primarily lamellar keratoplasties. There has also been an emergence of keratoprosthesis implants for eyes that are high risk of failure with penetrating keratoplasty. Consequently, there are different rates of glaucoma, pathogenesis, and potential treatment in the form of medical, laser, or surgical therapy.
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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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Fung SSM, Jabbour S, Harissi-Dagher M, Tan RRG, Hamel P, Baig K, Ali A. Visual Outcomes and Complications of Type I Boston Keratoprosthesis in Children: A Retrospective Multicenter Study and Literature Review. Ophthalmology 2017; 125:153-160. [PMID: 28807636 DOI: 10.1016/j.ophtha.2017.07.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2017] [Revised: 07/07/2017] [Accepted: 07/11/2017] [Indexed: 12/26/2022] Open
Abstract
PURPOSE To report outcomes and complications of Boston type 1 keratoprosthesis (KPro) implantation in children. DESIGN Retrospective, multicenter case series. PARTICIPANTS All children 16 years of age or younger who underwent KPro surgery at 3 ophthalmology centers in Canada between January 2010 and November 2014. METHODS Records of patients having undergone KPro implantation were reviewed. Data on preoperative characteristics, surgical procedure(s) performed, and postoperative outcomes were collected and analyzed. MAIN OUTCOME MEASURES Intraoperative and postoperative complications, device retention, and best-corrected visual acuity (BCVA). RESULTS The KPro was implanted in 11 eyes of 11 patients 0.9 to 15.5 years of age, with 6 being primary corneal procedures. Best-corrected visual acuity recorded before surgery ranged from 20/600 to light perception (LP), and vision in 2 eyes was fix and follow. All patients had been diagnosed with glaucoma and 6 eyes had glaucoma drainage devices (GDDs) inserted before KPro implantation. At last follow-up (mean, 41.8 months; range, 6.5-85.0 months), 2 eyes retained BCVA of 20/400 or better, whereas 5 eyes lost LP. Postoperative complications included retroprosthetic membrane (9 eyes), corneal melt (5 eyes), infectious keratitis (3 eyes), endophthalmitis (3 eyes), GDD erosion (2 eyes), and retinal detachment (5 eyes). The initial KPro was retained in 4 eyes (36.4%). CONCLUSIONS Boston type 1 keratoprosthesis implantation in children is associated with a substantially higher rate of complications, higher chance of device failure, and worse visual outcomes than observed in adults. In view of these results, the authors do not recommend the use of the KPro in the pediatric population.
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Affiliation(s)
- Simon S M Fung
- Department of Ophthalmology & Visual Sciences, Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Samir Jabbour
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal (CHUM), Hôpital Notre-Dame, Montréal, Canada
| | - Mona Harissi-Dagher
- Department of Ophthalmology, Centre Hospitalier de l'Université de Montréal (CHUM), Hôpital Notre-Dame, Montréal, Canada
| | - Reginald R G Tan
- Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Canada
| | - Patrick Hamel
- Department of Ophthalmology, CHU Ste-Justine, Montréal, Canada
| | - Kashif Baig
- Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Canada
| | - Asim Ali
- Department of Ophthalmology & Visual Sciences, Hospital for Sick Children, University of Toronto, Toronto, Canada.
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Lin M, Bhatt A, Haider A, Kim G, Farid M, Schmutz M, Mosaed S. Vision retention in early versus delayed glaucoma surgical intervention in patients with Boston Keratoprosthesis type 1. PLoS One 2017; 12:e0182190. [PMID: 28777800 PMCID: PMC5544178 DOI: 10.1371/journal.pone.0182190] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 07/13/2017] [Indexed: 11/18/2022] Open
Abstract
IMPORTANCE The loss of vision following Boston Keratoprosthesis (BKPro) surgery due to glaucoma occurs at a high frequency as diagnosis and management of glaucoma after this procedure pose challenges. OBJECTIVE To compare visual outcomes in patients undergoing Boston Keratoprosthesis surgery with and without prior or concurrent glaucoma surgery. DESIGN, SETTING, AND PARTICIPANTS This is a retrospective, observational cohort study of patients who underwent Boston Type I Keratoprosthesis surgery. 19 eyes of 18 patients who had undergone BKPro and met the inclusion criteria were identified. Twelve eyes received BKPro with prior or concurrent glaucoma surgery (Group 1), and seven eyes were identified undergoing BKPro surgery without prior or concurrent glaucoma surgery (Group 2). MAIN OUTCOMES AND MEASURES Main outcome included best corrected visual acuity at each follow up. RESULTS In Group 1, mean best corrected visual acuity (BCVA) within a year of BKPro surgery was 20/100 (range 20/40 to Count Fingers (CF); n = 12) and mean BCVA at 1 year from BKPro surgery was 20/115 (range 20/30 to CF; n = 12). 7 out of 12 patients retained or had improved BCVA at 1 year follow up after BKPro implantation, and 5 out of 12 patients had mild BCVA worsening. In Group 2, the mean BCVA within a year of BKPro surgery was 20/140 (ranging from 20/25 to hand motion vision (HM); n = 7) and mean BCVA at 1 year from BKPro surgery was Count Fingers (range 20/60 to Light Perception (LP); n = 6). 4 out of 6 patients lost significant vision at one year after BKPro. CONCLUSIONS AND RELEVANCE BKPro patients with early glaucoma surgical intervention retained vision significantly better compared to patients with late or no intervention. Our preliminary findings support the recommendation for concurrent or pre-emptive glaucoma surgical intervention in patients undergoing BKPro implantation.
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Affiliation(s)
- Mark Lin
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
| | - Anand Bhatt
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
- * E-mail:
| | - Asghar Haider
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
| | - Grace Kim
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
| | - Marjan Farid
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
| | - Mason Schmutz
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
| | - Sameh Mosaed
- University of California, Irvine, Department of Ophthalmology, Irvine, California, United States of America
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Huang YH, Tseng FW, Chang WH, Peng IC, Hsieh DJ, Wu SW, Yeh ML. Preparation of acellular scaffold for corneal tissue engineering by supercritical carbon dioxide extraction technology. Acta Biomater 2017; 58:238-243. [PMID: 28579539 DOI: 10.1016/j.actbio.2017.05.060] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 05/17/2017] [Accepted: 05/31/2017] [Indexed: 10/19/2022]
Abstract
In this study, we developed a novel method using supercritical carbon dioxide (SCCO2) to prepare acellular porcine cornea (APC). Under gentle extraction conditions using SCCO2 technology, hematoxylin and eosin staining showed that cells were completely lysed, and cell debris, including nuclei, was efficiently removed from the porcine cornea. The SCCO2-treated corneas exhibited intact stromal structures and appropriate mechanical properties. Moreover, no immunological reactions and neovascularization were observed after lamellar keratoplasty in rabbits. All transplanted grafts and animals survived without complications. The transplanted APCs were opaque after the operation but became transparent within 2weeks. Complete re-epithelialization of the transplanted APCs was observed within 4weeks. In conclusion, APCs produced by SCCO2 extraction technology could be an ideal and useful scaffold for corneal tissue engineering. STATEMENT OF SIGNIFICANCE We decellularized the porcine cornea using SCCO2 extraction technology and investigated the characteristics, mechanical properties, and biocompatibility of the decellularized porcine cornea by lamellar keratoplasty in rabbits. To the best of our knowledge, this is the first report describing the use of SCCO2 extraction technology for preparation of acellular corneal scaffold. We proved that the cellular components of porcine corneas had been efficiently removed, and the biomechanical properties of the scaffold were well preserved by SCCO2 extraction technology. SCCO2-treated corneas maintained optical transparency and exhibited appropriate strength to withstand surgical procedures. In vivo, the transplanted corneas showed no evidence of immunological reactions and exhibited good biocompatibility and long-term stability. Our results suggested that the APCs developed by SCCO2 extraction technology could be an ideal and useful scaffold for corneal replacement and corneal tissue engineering.
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Incidence, Risk Factors, and Surgical Management of Boston Type 1 Keratoprothesis Corneal Melts, Leaks, and Extrusions. Cornea 2017; 35:1049-56. [PMID: 27391092 DOI: 10.1097/ico.0000000000000911] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To determine the rate of Boston type 1 keratoprosthesis (Kpro)-related corneal melts, leaks, and extrusions requiring surgical repair and to analyze possible risk factors and visual outcomes. METHODS Retrospective chart review of 110 patients (128 eyes) who received a Kpro between November 2004 and December 2010 (average follow-up of 29 mo). The rate of corneal complications, risk factors for melts, and postmelt repair visual outcomes were evaluated. RESULTS Twenty eyes from 18 patients developed Kpro-related melts requiring surgical repair. The incidence of melt-related complications was 16%. In total, there were 33 episodes of melt-related complications. Surgical repair included lamellar patch grafts (15), Kpro removal with penetrating keratoplasty (7), reassembly of Kpro onto a new cornea (4), replacement of Kpro (3), suturing of a leak (3), and enucleation (1). The majority of eyes (18/20) did not regain their best post-Kpro vision at final follow-up (average 10 mo and range, 1-36 mo after melt repair). Significant risk factors for melt included previous infectious keratitis [P < 0.0001, odds ratio (OR) = 12.50, 95% confidence interval (CI), 4.02-38.9] and conjunctival deficiency (ie, a diagnosis of Stevens-Johnson syndrome, mucous membrane pemphigoid, or chemical injury, P = 0.043, OR = 2.66, CI, 1.01-7.02). CONCLUSIONS Patients who undergo Kpro with severe ocular surface disease are at greater risk for corneal melts, leaks, and extrusions. Patients with infectious keratitis and conjunctival deficiency are at an increased risk of developing corneal melts. Visual outcomes are poor after surgical repair of these complications.
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Outcomes of bilateral sequential implantation of the Boston keratoprosthesis type 1. Can J Ophthalmol 2017; 52:80-84. [PMID: 28237154 DOI: 10.1016/j.jcjo.2016.07.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 07/15/2016] [Accepted: 07/21/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To evaluate the risks and benefits of sequential bilateral Boston type 1 keratoprosthesis (KPro) implantation for bilateral corneal blindness. DESIGN Comparative retrospective study. PARTICIPANTS Patients who underwent a sequential bilateral KPro surgery. METHODS All 11 patients who underwent sequential bilateral KPro surgery at the Centre Hospitalier de l'Université de Montréal between October 2008 and October 2011 were recruited. Data from the 22 patient eyes in our study were separated in 2 groups based on the first (group 1) or second eye (group 2) implanted with the Kpro. Both groups were then compared for the best corrected visual acuity (BCVA) and complications. Bilateral BCVA following both surgeries and the overall number of complications that affected each patient after both interventions were also analyzed. RESULTS At 24 months, BCVA was 20/150 in group 1 and 20/200 in group 2 (p = 0.67). Throughout the study, there was no significant difference in BCVA between the 2 groups (p > 0.05), and bilateral BCVA was similar. The complication rate was comparable in the 2 groups. Patients had a mean of 2.45 complications following the first surgery and a mean of 5.27 in both eyes combined after the second intervention (p = 0.03). CONCLUSIONS Because visual gain observed following the second surgery was the same as that with the first and multiple surgeries increased the number of complications for each patient, we recommend saving bilateral KPro implantation for cases in which the first eye with KPro develops a disease limiting its visual potential.
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Endoscopic Cyclophotocoagulation for the Treatment of Glaucoma in Boston Keratoprosthesis Type II Patient. J Glaucoma 2017; 26:e146-e149. [PMID: 28079656 PMCID: PMC5380016 DOI: 10.1097/ijg.0000000000000626] [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: 11/26/2022]
Abstract
We describe the surgical technique of endoscopic cyclophotocoagulation in a Boston keratoprosthesis type II patient. This patient with ocular cicatricial pemphigoid had pars plana endoscopic cyclophotocoagula through wounds created in the eyelids.
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Al-Otaibi HM, Talea M, Kirat O, Stone DU, May WN, Kozak I. Streptococcus agalactiae Endophthalmitis in Boston Keratoprosthesis in a Patient with Steven-Johnson Syndrome. Middle East Afr J Ophthalmol 2016; 23:329-331. [PMID: 27994401 PMCID: PMC5141631 DOI: 10.4103/0974-9233.194095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A 25-year-old Syrian male with a previous episode of Stevens-Johnson syndrome with bilateral corneal cicatrization previously underwent surgery for Type 1 Boston Keratoprosthesis (K-Pro). Sixteen months after the K-Pro surgery, the patient presented with decreased vision to hand motion and microbial keratitis of the graft around the K-Pro with purulent discharge. Corneal scrapings were nonrevealing. B-scan in 3 days showed increased debris in the vitreous cavity and thickened retinochoroidal layer. Intravitreal tap and injections of vancomycin and ceftazidime were performed. The vitreous culture revealed β-hemolytic Streptococcus agalactiae; fungal cultures were negative. Repeat B-scan 3 days later demonstrated decreased vitreous opacity, and the patient felt more comfortable and was without pain. His visual acuity improved to 20/70, ocular findings have been stable for 9 months, and the patient continues to be monitored.
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Affiliation(s)
| | - Mohammed Talea
- King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Omar Kirat
- King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Donald U Stone
- King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia; Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA
| | - William N May
- King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia; Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Igor Kozak
- King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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Noel CW, Isenberg J, Goldich Y, Conlon R, Teichman J, Rubinger DA, Weinberg TAI, Slomovic J, Chan CC, Rootman DS, Baig KM, Slomovic AR. Type 1 Boston keratoprosthesis: outcomes at two Canadian centres. Can J Ophthalmol 2016; 51:76-82. [PMID: 27085262 DOI: 10.1016/j.jcjo.2015.12.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 11/24/2015] [Accepted: 12/06/2015] [Indexed: 11/19/2022]
Abstract
OBJECTIVES To report the outcomes of patients who underwent Boston type 1 keratoprosthesis (Kpro) surgery at the University Health Network (Toronto, Ont.) and the University of Ottawa Eye Institute (Ottawa, Ont.) between June 2008 and July 2013. DESIGN Retrospective case series. PARTICIPANTS Forty-four eyes of 43 patients who underwent Kpro surgery. METHODS A retrospective review was conducted of all Kpro procedures performed by 4 attending cornea surgeons. The preoperative characteristics and postoperative course of each patient were analyzed. RESULTS In 31 eyes (70%), the primary indication for a Kpro was failed corneal transplantation. The remaining 13 eyes (30%) had Kpro as a primary procedure. In all eyes, preoperative visual acuity (VA) was 20/150 or worse, with 39 eyes (89%) having a VA of counting fingers, hand movement, or light perception. Mean follow-up time was 21 ± 12 months (range 12-57 months). The retention rate at the last follow-up was 95%. Best-achieved median VA was 20/100 (range 20/20 to no light perception [NLP]), with 37% of patients achieving a VA of >20/40 at some point during their postoperative course. At the last follow-up, median VA was 20/400 (range 20/30 to NLP). The 2 most common complications included retroprosthetic membrane formation (23 eyes, 52%) and elevated intraocular pressure (10 eyes, 23%). There were 5 cases (11%) of stromal melt and 1 case (2%) of infective keratitis. CONCLUSIONS This study demonstrates that Kpro improves VA in a majority of cases, and is a viable option in situations in which there is a poor prognosis for traditional penetrating keratoplasty.
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Affiliation(s)
- Christopher W Noel
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont.
| | - Jordan Isenberg
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - Yakov Goldich
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - Ronan Conlon
- Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Ont
| | - Joshua Teichman
- Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Ont
| | - Daniel A Rubinger
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - Tessa A I Weinberg
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - Jaclyn Slomovic
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - Clara C Chan
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - David S Rootman
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
| | - Kashif M Baig
- Ottawa Hospital Research Institute, University of Ottawa Eye Institute, Ottawa, Ont
| | - Allan R Slomovic
- Department of Ophthalmology, Toronto Western Hospital, University of Toronto, Toronto, Ont
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Sevgi DD, Fukuoka H, Afshari NA. 20 Years of Advances in Keratoprosthesis. CURRENT OPHTHALMOLOGY REPORTS 2016. [DOI: 10.1007/s40135-016-0107-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Sequential versus concomitant surgery of glaucoma drainage implant and Boston keratoprosthesis type 1. Eur J Ophthalmol 2016; 26:556-563. [PMID: 27079206 DOI: 10.5301/ejo.5000794] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/24/2016] [Indexed: 11/20/2022]
Abstract
PURPOSE To compare sequential versus concomitant surgery of glaucoma drainage implant (GDI) and Boston keratoprosthesis type 1 (KPro). METHODS Patients who received GDI and KPro in the same eye were divided into 2 groups: GDI placement prior to KPro surgery (sequential group) or GDI placement concomitant with KPro surgery (concomitant group). Main outcome measures were GDI failure, defined as intraocular pressure (IOP) >21 mm Hg, less than a 20% IOP reduction from baseline, or IOP <5 mm Hg on 2 consecutive follow-up visits, any reoperation for glaucoma, or loss of light perception; best-corrected visual acuity (BCVA); and surgical complications. RESULTS Thirty-five eyes were included in the study: 17 in the sequential group and 18 in the concomitant group. The cumulative incidence of failure after 5 years of follow-up was 23.5% in the sequential group and 27.8% in the concomitant group (p = 0.250). Mean BCVA was significantly better in the concomitant group after 6 months, 1 year, 2 years, and at the last follow-up (p<0.05). Both groups had similar rates of complications (p = 1.000). The most frequent complication was GDI erosion, which occurred in 23.5% (n = 4/17) in the sequential group and in 27.8% (n = 5/18) in the concomitant group (p = 1.000). CONCLUSIONS Glaucoma drainage implant placement at the time of KPro surgery had similar cumulative incidence of failure, but significantly favorable visual outcomes, compared to sequential surgeries. The most frequent complication was GDI erosion, occurring in approximately one fourth of the patients.
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Kishore V, Iyer R, Frandsen A, Nguyen TU. In vitro characterization of electrochemically compacted collagen matrices for corneal applications. ACTA ACUST UNITED AC 2016; 11:055008. [PMID: 27710923 DOI: 10.1088/1748-6041/11/5/055008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Loss of vision due to corneal disease is a significant problem worldwide. Transplantation of donor corneas is a viable treatment option but limitations such as short supply and immune-related complications call for alternative options for the treatment of corneal disease. A tissue engineering-based approach using a collagen scaffold is a promising alternative to develop a bioengineered cornea that mimics the functionality of native cornea. In this study, an electrochemical compaction method was employed to synthesize highly dense and transparent collagen matrices. We hypothesized that chemical crosslinking of electrochemically compacted collagen (ECC) matrices will maintain transparency, improve stability, and enhance the mechanical properties of the matrices to the level of native cornea. Further, we hypothesized that keratocyte cell viability and proliferation will be maintained on crosslinked ECC matrices. The results indicated that uncrosslinked and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide-N-hydroxysuccinimide (EDC-NHS) crosslinked ECC matrices were highly transparent with light transmission measurements comparable to native cornea. Stability tests showed that while the uncrosslinked ECC matrices degraded within 6 h when treated with collagenase, EDC-NHS or genipin crosslinking significantly improved the stability of ECC matrices (192 h for EDC-NHS and 256 h for genipin). Results from the mechanical tests showed that both EDC-NHS and genipin crosslinking significantly improved the strength and modulus of ECC matrices. Cell culture studies showed that keratocyte cell viability and proliferation are maintained on EDC-NHS crosslinked ECC matrices. Overall, results from this study suggest that ECC matrices have the potential to be developed as a functional biomaterial for corneal repair and regeneration.
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Affiliation(s)
- Vipuil Kishore
- Department of Chemical Engineering, Florida Institute of Technology, Melbourne, FL 32901, USA. Department of Biomedical Engineering, Florida Institute of Technology, Melbourne, FL 32901, USA. Author to whom any correspondence should be addressed. Department of Chemical Engineering, Florida Institute of Technology, 150 W. University Blvd, Melbourne, FL 32901, USA
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Safety of Concurrent Boston Type I Keratoprosthesis and Glaucoma Drainage Device Implantation. Ophthalmology 2016; 124:12-19. [PMID: 27614591 DOI: 10.1016/j.ophtha.2016.08.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 08/01/2016] [Accepted: 08/02/2016] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To evaluate the safety of concurrent Boston type I keratoprosthesis (KPro) and glaucoma drainage device (GDD) implantation. DESIGN Retrospective comparative study of a consecutive cohort of patients. SUBJECTS Patients who underwent KPro implantation by a single surgeon (A.J.A.) with or without 1 concurrent Ahmed GDD (New World Medical, Inc., Rancho Cucamonga, CA) implantation between January 1, 2005, and January 31, 2015, were included. Patients with fewer than 3 months of follow-up or a history of previous KPro implantation were excluded. METHODS Preoperative, operative, and postoperative data were collected for each procedure. All comparisons were made between KPro procedures performed with or without concurrent GDD implantation. The Fisher exact test (2-tailed) was used to compare proportions, Student t test and Wilcoxon rank-sum test were used to compare means, and the log-rank test was used to compare time-to-outcome events. MAIN OUTCOME MEASURES The primary outcome was frequency of the composite variable, that is, any serious vision-threatening postoperative complication, which included sterile vitreitis, endophthalmitis, hypotony maculopathy, suprachoroidal hemorrhage, retinal detachment, stromal necrosis, and infectious keratitis. Secondary outcomes included intraocular pressure control, worsening of visual acuity, cystoid macular edema, retroprosthetic membrane formation, persistent epithelial defect formation, GDD exposure, and KPro removal. RESULTS One hundred thirty-seven KPro procedures were performed in 129 patients: 91 (66.4%) KPro alone and 46 (33.6%) KPro plus GDD. There were no statistically significant differences between the 2 groups in terms of the incidence of vision-threatening postoperative complications. None of the 46 GDDs placed at the same time as the KPro became exposed during an average follow-up of 44 months. CONCLUSIONS Compared with KPro alone, GDD placement combined with KPro was not associated with increased postoperative complications.
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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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Lee R, Khoueir Z, Tsikata E, Chodosh J, Dohlman CH, Chen TC. Long-term Visual Outcomes and Complications of Boston Keratoprosthesis Type II Implantation. Ophthalmology 2016; 124:27-35. [PMID: 27538795 DOI: 10.1016/j.ophtha.2016.07.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 06/11/2016] [Accepted: 07/10/2016] [Indexed: 10/21/2022] Open
Abstract
PURPOSE To report the long-term visual outcomes and complications after Boston keratoprosthesis type II implantation in the largest single-center case series with the longest average follow-up. DESIGN Retrospective review of consecutive clinical case series. PARTICIPANTS Between January 1992 and April 2015 at the Massachusetts Eye and Ear Infirmary, 48 eyes of 44 patients had keratoprosthesis type II implanted by 2 surgeons (C.H.D. and J.C.). METHODS For each eye, data were collected and analyzed on the preoperative characteristics, intraoperative procedures, and postoperative course. MAIN OUTCOME MEASURES Visual acuity outcomes, postoperative complications, and device retention. RESULTS The most common indications for surgery were Stevens-Johnson syndrome in 41.7% (20 of 48 eyes) and mucous membrane pemphigoid in 41.7% (20 of 48 eyes). Mean follow-up duration was 70.2 months (standard deviation, 61.8 months; median, 52 months; range, 6 months to 19.8 years). Almost all patients (95.8%, 46 of 48 eyes) had a preoperative visual acuity of 20/200 or worse. Postoperative visual acuity improved to 20/200 or better in 37.5% (18 of 48 eyes) and to 20/100 or better in 33.3% (16 of 48 eyes) at the last follow-up visit. The most common postoperative complication was retroprosthetic membrane formation in over half (60.4%, 29 of 48 eyes). The most pressing postoperative complication was glaucoma onset or progression in about a third. Preexisting glaucoma was present in 72.9% (35 of 48 eyes). Glaucoma progressed in 27.1% (13 of 48 eyes) and was newly diagnosed in 8.3% (4 of 48 eyes) after surgery. Other postoperative complications were tarsorrhaphy revision in 52.1% (25 of 48 eyes), retinal detachment in 18.8% (9 of 48 eyes), infectious endophthalmitis in 6.3% (3 of 48 eyes), and choroidal detachment or hemorrhage in 8.3% (4 of 48 eyes). Half of eyes retained their initial keratoprosthesis at the last follow-up (50.0%, 24 of 48 eyes). CONCLUSIONS The Boston keratoprosthesis type II is a viable option to salvage vision in patients with poor prognosis for other corneal procedures. Retroprosthetic membranes, keratoprosthesis retention, and glaucoma are major challenges in the postoperative period; however, the keratoprosthesis can still provide improved vision in a select group of patients.
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Affiliation(s)
- Ramon Lee
- Harvard Medical School, Boston, Massachusetts
| | - Ziad Khoueir
- Glaucoma Service, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Edem Tsikata
- Glaucoma Service, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - James Chodosh
- Cornea Service, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Claes H Dohlman
- Cornea Service, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Teresa C Chen
- Glaucoma Service, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts.
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Innovative approaches to glaucoma management of Boston keratoprosthesis type 1. CURRENT OPHTHALMOLOGY REPORTS 2016; 4:147-153. [PMID: 28529825 DOI: 10.1007/s40135-016-0102-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Glaucoma remains a prevalent disorder and visual limiting factor after Boston keratoprosthesis type 1 implantation. Patients with glaucoma have worse initial and late visual acuity outcomes after otherwise successful keratoprosthesis implantation. Management of glaucoma in the setting of a keratoprosthesis is challenging because of relatively rapid progression and an inability to accurately measure intraocular pressure (IOP). In addition, there are no standard guidelines for glaucoma surveillance and monitoring after keratoprosthesis surgery. This report provides a review of the current literature and offers innovative strategies that will overcome the challenges in managing glaucoma in the setting of a Boston keratoprosthesis type 1 implant. The topics that will be discussed in this section include alternative methods for IOP measurement, rationales and surgical techniques for a pars plana tube placement for glaucoma drainage device, effective medical and laser treatment, the risk for IOP elevations after YAG laser, and practical guides to glaucoma surveillance and monitoring.
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Abstract
PURPOSE OF REVIEW Intraocular pressure (IOP) elevation and glaucoma progression following corneal transplantation, specifically, penetrating keratoplasty, Descemet's stripping endothelial keratoplasty, and Boston keratoprosthesis, are well described causes of ocular morbidity. Depending on the procedure performed, the incidence of glaucoma is highly variable. Several etiologic factors have been identified, the most common being synechial angle closure and corticosteroid-induced IOP elevation. The purpose of this review is to describe the various treatment strategies for glaucoma following corneal transplantation. RECENT FINDINGS Medications and laser treatments are usually first-line therapies for postoperative IOP elevation. Surgical intervention, including filtering surgery and glaucoma drainage devices, may be necessary to control IOP and prevent progressive glaucomatous damage. SUMMARY Glaucoma is a common complication of corneal transplantation, and the degree of aggressiveness is often related to the indication for corneal surgery. Although postoperative IOP elevation may be controlled with medical therapy alone, refractory cases may require glaucoma surgery. In all cases, early detection and intervention are necessary to optimize patient outcomes.
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Hashimoto Y, Hattori S, Sasaki S, Honda T, Kimura T, Funamoto S, Kobayashi H, Kishida A. Ultrastructural analysis of the decellularized cornea after interlamellar keratoplasty and microkeratome-assisted anterior lamellar keratoplasty in a rabbit model. Sci Rep 2016; 6:27734. [PMID: 27291975 PMCID: PMC4904214 DOI: 10.1038/srep27734] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 05/24/2016] [Indexed: 12/13/2022] Open
Abstract
The decellularized cornea has received considerable attention for use as an artificial cornea. The decellularized cornea is free from cellular components and other immunogens, but maintains the integrity of the extracellular matrix. However, the ultrastructure of the decellularized cornea has yet to be demonstrated in detail. We investigated the influence of high hydrostatic pressure (HHP) on the decellularization of the corneal ultrastructure and its involvement in transparency, and assessed the in vivo behaviour of the decellularized cornea using two animal transplantation models, in relation to remodelling of collagen fibrils. Decellularized corneas were prepared by the HHP method. The decellularized corneas were executed by haematoxylin and eosin and Masson's trichrome staining to demonstrate the complete removal of corneal cells. Transmission electron microscopy revealed that the ultrastructure of the decellularized cornea prepared by the HHP method was better maintained than that of the decellularized cornea prepared by the detergent method. The decellularized cornea after interlamellar keratoplasty and microkeratome-assisted anterior lamellar keratoplasty using a rabbit model was stable and remained transparent without ultrastructural alterations. We conclude that the superior properties of the decellularized cornea prepared by the HHP method were attributed to the preservation of the corneal ultrastructure.
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Affiliation(s)
- Yoshihide Hashimoto
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
| | - Shinya Hattori
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
| | - Shuji Sasaki
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
- Department of Ophthalmology, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takako Honda
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
| | - Tsuyoshi Kimura
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
| | - Seiichi Funamoto
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
| | - Hisatoshi Kobayashi
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
| | - Akio Kishida
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, Tokyo, Japan
- World Premier International Research Center Initiative, International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Ibaraki, Japan
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Abstract
The cornea focuses external light onto the retina, a function for which it must be transparent and possess a smooth surface. Homeostasis of the corneal epithelium is regulated by various humoral factors present in the tear fluid and by neural factors derived from the trigeminal nerve. Neurotrophic keratopathy (NK) is characterized by corneal epithelial disorders that result from impairment of trigeminal nerve function and a consequent deficiency of neural factors. The ideal mode of treatment for this condition is the regeneration of damaged trigeminal nerve fibers, but such therapy is not currently available. In this review, we describe established and potential new treatments of NK. Our research demonstrated that a combination of the neurotransmitter substance P and insulin-like growth factor 1 (IGF-1) has a synergistic stimulatory effect on corneal epithelial migration in vitro and on corneal wound closure in vivo. Furthermore, we identified the minimal amino acid sequences of substance P and IGF-1 required for this synergistic action based on the assumption that the clinical application of peptides corresponding to these sequences would have fewer side effects compared with the full-length molecules. Combination of the substance P-derived peptide FGLM-amide and the IGF-1-derived peptide SSSR promoted corneal epithelial wound healing in patients with NK.Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01756456.
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Current Perspectives of Prophylaxis and Management of Acute Infective Endophthalmitis. Adv Ther 2016; 33:727-46. [PMID: 26935830 DOI: 10.1007/s12325-016-0307-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Indexed: 12/23/2022]
Abstract
Endophthalmitis is an intraocular inflammatory condition which may or may not be caused by infective agents. Noninfectious (sterile) endophthalmitis may be attributable to various causes including postoperative retained soft lens matter or toxicity following introduction of other agents into the eye. Infectious endophthalmitis is further subdivided into endogenous and exogenous. In endogenous endophthalmitis there is hematogenous spread of organisms from a distant source of infection whereas in exogenous endophthalmitis direct microbial inoculation may occur usually following ocular surgery or penetrating eye injury with or without intraocular foreign bodies. Acute infective endophthalmitis is usually exogenous induced by inoculation of pathogens following ocular surgery, open-globe injury and intravitreal injections. More infrequently the infective source is internal and septicemia spreads to the eye resulting in endogenous endophthalmitis. Several risk factors have been implicated including immunosuppression, ocular surface abnormalities, poor surgical wound construction, complicated cataract surgery with vitreous loss and certain types of intraocular lens. Comprehensive guidelines and recommendations on prophylaxis and monitoring of surgical cases have been proposed to minimize the risk of acute endophthalmitis. Early diagnosis and prompt management of infective endophthalmitis employing appropriately selected intravitreal antibiotics are essential to optimize visual outcome.
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Abstract
PURPOSE To report the results of unilateral implantation of a Boston keratoprosthesis (BKPro) in patients with good visual acuity in the fellow eye. METHODS A retrospective analysis of 37 eyes of 37 patients who underwent an optical BKPro and had a preoperative best-corrected visual acuity (BCVA) of 20/40 or better in the fellow eye at Wills Eye Hospital from September 2005 to November 2013 was performed. Patients were excluded if they had less than 1 year of postoperative follow-up. RESULTS The mean follow-up after BKPro implantation was 31.7 months (range, 12-78 months; SD, 21). Twenty-eight patients underwent a BKPro for failed penetrating keratoplasty, and 9 patients underwent a primary BKPro. The most common complications were elevated intraocular pressure and retroprosthetic membrane formation in 16 eyes (43%) each. The mean final BCVA (1.0 ± 0.8 logMAR; median, 1.0 logMAR) was statistically better than the mean preoperative BCVA (1.8 ± 0.2 logMAR; median, 1.8 logMAR) (P < 0.001). The probability of postoperative BCVA of 20/200 or better was 54.1% with an average 45.1 ± 4.7 (confidence interval: 35.9-54.3) months of follow-up. The probability of postoperative BCVA of 20/40 or better was 37.8% with an average 51.8 ± 4.9 (confidence interval: 42.0-61.5) months of follow-up. CONCLUSIONS Half of the patients in our study achieved the minimum visual acuity required for binocular functioning, whereas one-third of the patients achieved a BCVA somewhat similar to that of the contralateral eye. The complications were similar to those reported previously with good retention of the device. BKPro implantation is a reasonable option for patients with good vision in the fellow eye.
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Visual Acuity Outcomes of the Boston Keratoprosthesis Type 1: Multicenter Study Results. Am J Ophthalmol 2016; 162:89-98.e1. [PMID: 26550696 DOI: 10.1016/j.ajo.2015.10.023] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 11/21/2022]
Abstract
PURPOSE To report logarithm of the minimal angle of resolution (logMAR) visual outcomes of the Boston keratoprosthesis type 1. DESIGN Prospective cohort study. METHODS Preoperative, intraoperative, and postoperative parameters of 300 eyes of 300 patients who underwent implantation of a Boston keratoprosthesis type 1 device between January 2003 and July 2008 by 1 of 19 surgeons at 18 medical centers were collected. RESULTS After an average of 17.1 ± 14.8 months, visual acuity improved significantly (P < .0001) to a mean final value of 0.89 ± 0.64 (20/150). There were also significantly fewer eyes with light perception (6.7%; n = 19; P < .0001), although 3.1% (n = 9) progressed to no light perception. There was no association between age (P = .08), sex (P = .959), operative side (P = .167), or failure (P = .494) and final visual acuity. The median time to achieve 20/200 visual acuity was 1 month (95% confidence interval 1.0-6.0) and it was retained for an average of 47.8 months. Multivariate analysis, controlling for preoperative visual acuity, demonstrated 2 factors associated with final visual outcome: chemical injury was associated with better final vision (P = .007), whereas age-related macular degeneration was associated with poorer vision (P < .0001). CONCLUSIONS The Boston keratoprosthesis type 1 is an effective device for rehabilitation in advanced ocular surface disease, resulting in a significant improvement in visual acuity. Eyes achieved a mean value of 20/150 (0.89 ± 0.64 logMAR units) after 6 months and this was relatively stable thereafter. The best visual prognosis is observed in chemical injury eyes, whereas the worst prognosis is in aniridia, although the latter has limited visual potential.
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Jain R, Sharma N, Basu S, Iyer G, Ueta M, Sotozono C, Kannabiran C, Rathi VM, Gupta N, Kinoshita S, Gomes JAP, Chodosh J, Sangwan VS. Stevens-Johnson syndrome: The role of an ophthalmologist. Surv Ophthalmol 2016; 61:369-99. [PMID: 26829569 DOI: 10.1016/j.survophthal.2016.01.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2015] [Revised: 01/22/2016] [Accepted: 01/25/2016] [Indexed: 01/03/2023]
Abstract
Stevens-Johnson syndrome (SJS) is an acute blistering disease of the skin and mucous membranes. Acute SJS leads to the acute inflammation of the ocular surface and chronic conjunctivitis. If not properly treated, it causes chronic cicatricial conjunctivitis and cicatricial lid margin abnormalities. Persistent inflammation and ulceration of the ocular surface with cicatricial complications of the lids leads to chronic ocular sequelae, ocular surface damage, and corneal scarring. The destruction of the glands that secrete the tear film leads to a severe form of dry eye that makes the management of chronic SJS difficult. The option that is routinely used for corneal visual rehabilitation, keratoplasty, is best avoided in such cases. We describe the management strategies that are most effective during the acute and chronic stages of SJS. Although treatments for acute SJS involve immunosuppressive and immunomodulatory therapies, amniotic membrane transplantation is also useful. The options for visual rehabilitation in patients with chronic SJS are undergoing radical change. We describe the existing literature regarding the management of SJS and highlight recent advances in the management of this disorder.
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Affiliation(s)
- Rajat Jain
- Cornea, Ocular Surface and Anterior Segment Services, Department of Ophthalmology, drishtiCONE Eye Care, New Delhi, India
| | - Namrata Sharma
- Cornea and Refractive Surgery Services, Department of Ophthalmology, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India
| | - Sayan Basu
- Cornea and Anterior Segment Services, Department of Ophthalmology, L V Prasad Eye Institute, Hyderabad, Telangana, India
| | - Geetha Iyer
- C J Shah Cornea Services, Department of Ophthalmology, Dr. G Sitalakshmi Memorial Clinic for Ocular Surface Disorders, Sankara Nethralaya, Chennai, India
| | - Mayumi Ueta
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan; Department of Ophthalmology, Doshisha University, Kyotanabe, Japan
| | - Chie Sotozono
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Chitra Kannabiran
- Department of Ophthalmology, Kallam Anji Reddy Molecular Genetics Laboratory, L V Prasad Eye Institute (LVPEI), Hyderabad, Telangana, India
| | - Varsha M Rathi
- Cornea Services, Department of Ophthalmology, L V Prasad Eye Institute, Hyderabad, Telangana, India
| | - Nidhi Gupta
- Department of Ophthalmology, Dr. Shroff Charity Eye Hospital, Delhi, India
| | - Shigeru Kinoshita
- Department of Ophthalmology, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - José A P Gomes
- Cornea and External Disease Service, Department of Ophthalmology, Federal University of Sao Paulo/Escola Paulista de Medicina (UNIFESP/EPM), São Paulo, Brazil; Advanced Ocular Surface Center (CASO), Department of Ophthalmology, Federal University of Sao Paulo/Escola Paulista de Medicina (UNIFESP/EPM), São Paulo, Brazil
| | - James Chodosh
- Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts, USA
| | - Virender S Sangwan
- Department of Ophthalmology, Srujana Center for Innovation, L V Prasad Eye Institute, Hyderabad, Telangana, India.
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Ahmad S, Mathews PM, Srikumaran D, Aldave AJ, Lenis T, Aquavella JV, Hannush SB, Belin M, Akpek EK. Outcomes of Repeat Boston Type 1 Keratoprosthesis Implantation. Am J Ophthalmol 2016; 161:181-7.e1. [PMID: 26482467 DOI: 10.1016/j.ajo.2015.10.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 10/07/2015] [Accepted: 10/07/2015] [Indexed: 11/30/2022]
Abstract
PURPOSE To describe the outcomes and prognostic characteristics of patients who had a repeat Boston type 1 keratoprosthesis (KPro) implantation. DESIGN Retrospective case series. METHODS setting: Data regarding preoperative clinical and demographic characteristics and postoperative course during initial and repeat KPro placement were collected at multiple centers across the country. PATIENTS Forty-eight eyes underwent explantation of KPro owing to complications between September 2003 and August 2014 at 5 participating tertiary eye care centers in the United States. Of those, 36 eyes that received a subsequent replacement device were included. MAIN OUTCOME MEASURES Visual acuity (VA) outcomes and postoperative complications. RESULTS Ocular surface disease was significantly more common in eyes that required a device explantation, compared to those that retained the device (P < .001). Sixty-seven percent of eyes (24/36) achieved VA ≥ 20/200 vision after the repeat KPro. The probability of these 24 eyes maintaining VA ≥ 20/200 after the repeat KPro was 87% at 1 year and 75% at 2 years. Predictors of the ability to maintain vision ≥ 20/200 following surgery were a better last-recorded vision before explantation (P = .0002) and better vision immediately after repeat KPro (P < .001). CONCLUSION Ocular surface disease and its complications were associated with more frequent device removal. In these patients, repeat KPro resulted in restoration of vision. A reasonable visual acuity prior to device removal was associated with favorable long-term postoperative visual acuity and retention.
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Affiliation(s)
- Sumayya Ahmad
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Priya M Mathews
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Divya Srikumaran
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Tamara Lenis
- The Stein Eye Institute, Los Angeles, California
| | | | | | - Michael Belin
- University of Arizona Department of Ophthalmology, Tucson, Arizona
| | - Esen Karamursel Akpek
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland.
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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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87
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Riau AK, Mondal D, Aung TT, Murugan E, Chen L, Lwin NC, Zhou L, Beuerman RW, Liedberg B, Venkatraman SS, Mehta JS. Collagen-Based Artificial Corneal Scaffold with Anti-Infective Capability for Prevention of Perioperative Bacterial Infections. ACS Biomater Sci Eng 2015; 1:1324-1334. [DOI: 10.1021/acsbiomaterials.5b00396] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Andri K. Riau
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Debasish Mondal
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Thet T. Aung
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Elavazhagan Murugan
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Liyan Chen
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Nyein C. Lwin
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Lei Zhou
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Roger W. Beuerman
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Bo Liedberg
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Subbu S. Venkatraman
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
| | - Jodhbir S. Mehta
- ‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore
- §Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore
- Duke-NUS Graduate Medical School, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
- Singapore National Eye Center, Singapore
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Konstantopoulos A, Tan XW, Goh GTW, Saraswathi P, Chen L, Nyein CL, Zhou L, Beuerman R, Tan DTH, Mehta J. Prophylactic Vancomycin Drops Reduce the Severity of Early Bacterial Keratitis in Keratoprosthesis. PLoS One 2015; 10:e0139653. [PMID: 26460791 PMCID: PMC4604170 DOI: 10.1371/journal.pone.0139653] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 08/16/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Artificial cornea transplantation, keratoprosthesis, improves vision for patients at high risk of failure with human cadaveric cornea. However, post-operative infection can cause visual loss and implant extrusion in 3.2-17% of eyes. Long-term vancomycin drops are recommended following keratoprosthesis to prevent bacterial keratitis. Evidence, though, in support of this practice is poor. We investigated whether prophylactic vancomycin drops prevented bacterial keratitis in an animal keratoprosthesis model. METHODOLOGY Twenty-three rabbits were assigned either to a prophylactic group (n = 13) that received vancomycin 1.4% drops 5 times/day from keratoprosthesis implantation to sacrifice, or a non-prophylactic group (n = 10) that received no drops. All rabbits had Staphylococcus aureus inoculation into the cornea at 7-12 days post-implantation and were sacrificed at predetermined time-points. Prophylactic and non-prophylactic groups were compared with slit-lamp photography (SLP), anterior segment optical coherence tomography (AS-OCT), and histology, immunohistochemistry and bacterial quantification of excised corneas. Corneal vancomycin pharmacokinetics were studied in 8 additional rabbits. RESULTS On day 1 post-inoculation, the median SLP score and mean±SEM AS-OCT corneal thickness (CT) were greater in the non-prophylactic than the prophylactic group (11 vs. 1, p = 0.049 and 486.9±61.2 vs. 327.4±37.1 μm, p = 0.029 respectively). On days 2 and 4, SLP scores and CT were not significantly different. Immunohistochemistry showed a greater CD11b+ve/non-CD11b+ve cell ratio in the non-prophylactic group (1.45 vs. 0.71) on day 2. Bacterial counts were not significantly different between the two groups. Corneal vancomycin concentration (2.835±0.383 μg/ml) exceeded minimum inhibitory concentration (MIC) for Staphylococcus aureus only after 16 days of vancomycin drops. Two of 3 rabbits still developed infection despite bacterial inoculation after 16 days of prophylactic drops. CONCLUSIONS Prophylactic vancomycin drops provided short-term benefit, but did not prevent infection. Achieving MIC in the cornea was not sufficient to prevent Staphylococcus aureus keratitis. Patients should continue to be counselled regarding the risk of infection following keratoprosthesis.
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Affiliation(s)
- Aris Konstantopoulos
- Singapore Eye Research Institute, Singapore
- Singapore National Eye Centre, Singapore
| | | | | | | | - Liyan Chen
- Singapore Eye Research Institute, Singapore
| | | | - Lei Zhou
- Singapore Eye Research Institute, Singapore
| | | | - Donald Tiang Hwee Tan
- Singapore Eye Research Institute, Singapore
- Singapore National Eye Centre, Singapore
- Department of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore
| | - Jod Mehta
- Singapore Eye Research Institute, Singapore
- Singapore National Eye Centre, Singapore
- Department of Clinical Sciences, Duke-NUS Graduate Medical School, Singapore
- Nanyang Technological University, Singapore
- * E-mail:
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89
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Sharma N, Falera R, Arora T, Agarwal T, Bandivadekar P, Vajpayee RB. Evaluation of a low-cost design keratoprosthesis in end-stage corneal disease: a preliminary study. Br J Ophthalmol 2015; 100:323-7. [DOI: 10.1136/bjophthalmol-2015-306982] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 07/08/2015] [Indexed: 12/27/2022]
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90
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Haugsdal JM, Goins KM, Greiner MA, Kwon YH, Alward WLM, Wagoner MD. Boston type 1 keratoprosthesis for primary congenital glaucoma. Br J Ophthalmol 2015. [DOI: 10.1136/bjophthalmol-2015-307190] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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91
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Grassi CM, Crnej A, Paschalis EI, Colby KA, Dohlman CH, Chodosh J. Idiopathic vitritis in the setting of Boston keratoprosthesis. Cornea 2015; 34:165-70. [PMID: 25526075 DOI: 10.1097/ico.0000000000000328] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE The aim of this study was to revisit the clinical paradigm attributed to Boston keratoprosthesis recipients presenting with idiopathic vitreous inflammation. METHODS A retrospective chart review was performed of keratoprosthesis recipients at Massachusetts Eye and Ear Infirmary, from January 2000 to August 2013, for demographic data, indication(s) for surgery, timing and presentation of vitreous inflammation, and best-corrected visual acuity at baseline, on presentation, and after resolution of vitritis. RESULTS Twenty-three (23 eyes) of 346 patients developed idiopathic vitreous inflammation after keratoprosthesis implantation. Six of 23 patients presented with signs and symptoms similar to infectious endophthalmitis but were culture negative. The proportion of patients who fit the previous paradigm of sudden painless loss of vision without external signs of infection ("sterile vitritis") at their first presentation with vitritis was only 4 of 23. Vision decline was variable (median, 9 lines on Snellen chart; range, 0-24), as was time to recovery of best vision (median, 8.9 weeks; range, 0.9-36.7). Nine eyes had repeat bouts (43 episodes in 23 patients). Ten of 43 episodes did not recover to baseline vision. Seventeen of 23 eyes with idiopathic vitritis after keratoprosthesis later developed other complications. CONCLUSIONS The current paradigm for idiopathic vitritis after keratoprosthesis implantation includes sudden painless loss of vision with full recovery of vision on treatment with periocular corticosteroids. However, idiopathic vitritis after keratoprosthesis can also mimic infectious endophthalmitis with pain and external signs of inflammation. Visual loss can be gradual. Vision may not recover to baseline despite treatment. Vitritis may be a part of a common pathway of chronic inflammation after keratoprosthesis.
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Affiliation(s)
- Christina M Grassi
- Department of Ophthalmology, Harvard Medical School, Massachusetts Eye Infirmary, Boston, MA
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92
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Ocular surface, fornix, and eyelid rehabilitation in Boston type I keratoprosthesis patients with mucous membrane disease. Ophthalmic Plast Reconstr Surg 2015; 31:43-9. [PMID: 24911535 DOI: 10.1097/iop.0000000000000172] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To understand the efficacy of various approaches for ocular surface reconstruction in eyes with implanted Boston Type I keratoprosthesis. METHODS All eyes implanted with a Boston Type I keratoprosthesis over a 9-year period by a single surgeon were reviewed. Any case in which mucosal rehabilitation was performed was included in the study sample. The type, number, approach, and outcome for all eyelid and ocular surface procedures were assessed. RESULTS A total of 22 mucosal surface surgeries were performed before, concurrent with, and after implantation of 11 keratoprostheses and 1 penetrating keratoplasty (after keratoprosthesis removal) in 9 eyes of 9 patients. Most of the ocular surface reconstructive surgeries (81.8%; 18/22) were performed at the time of or following keratoprosthesis implantation, with the most common indication being corneal stromal necrosis (44.4%; 8/18). Free grafting and simple advancement resulted in graft retraction for each case, and pedicle or bucket handle flaps resulted in a stable vascularized graft for half of the cases. Graft retraction occurred in 6 of the 9 eyes in this study, including in all 5 eyes of patients with Stevens Johnsons syndrome (SJS). CONCLUSIONS Free grafting and simple advancement flaps do not appear to be effective for rehabilitation in these eyes. However, even vascularized pedicle and bucket handle flaps retracted 50% of the time. Individuals with SJS were more likely to both require conjunctival rehabilitation after keratoprosthesis surgery and develop graft retraction in the course of management.
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93
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Boston type 1 keratoprosthesis for failed keratoplasty. Int Ophthalmol 2015; 36:73-78. [PMID: 25975459 DOI: 10.1007/s10792-015-0078-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 04/27/2015] [Indexed: 10/23/2022]
Abstract
The purpose of this study was to evaluate the outcomes of the Boston type 1 keratoprosthesis (Kpro-1) in eyes with failed keratoplasty. A retrospective review was performed of every patient treated with a Kpro-1 at a tertiary eye care center between January 1, 2008 and July 1, 2013. Eyes with a failed keratoplasty originally performed for corneal edema, trauma, or keratoconus were included in the statistical analysis. The main outcome measures were visual outcome, prosthesis retention, and postoperative complications. Twenty-four eyes met the inclusion criteria, including 13 eyes with corneal edema, 8 eyes with trauma, and 3 eyes with keratoconus. After a mean follow-up period of 28.9 months (range 7-63 months), the median best corrected visual acuity (BCVA) was 20/125. The BCVA was ≥ 20/40 in 4 (16.7 %) eyes, ≥ 20/70 in 9 (37.5 %) eyes, and ≥ 20/200 in 14 (58.3 %) eyes. Overall, the postoperative BCVA improved in 17 (70.9 %) eyes, was unchanged in 3 (12.5 %) eyes, and was worse in 4 (16.7 %) eyes. The initial Kpro-1 was retained in 22 (91.7 %) eyes, and was successfully repeated in the other 2 eyes. One or more serious prosthesis- or sight-threatening complications occurred in 8 (33.3 %) eyes. These included 1 case of wound dehiscence leading to prosthesis extrusion, 1 case of fungal keratitis leading to prosthesis extrusion, 4 cases of endophthalmitis, and 5 retinal detachments. The Boston Kpro-1 is associated with an excellent prognosis for prosthesis retention and satisfactory visual improvement in eyes with previous failed keratoplasty.
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Abstract
Glaucoma is the leading cause of irreversible vision loss post-keratoplasty and an important cause of graft failure. With newer techniques, such as lamellar, endothelial, and laser-assisted keratoplasty as well as keratoprosthesis gaining popularity, clinicians will need to consider the incidence, risks, evaluation, and management of glaucoma for each type of keratoplasty when determining which type of transplant may be most appropriate. A comprehensive literature search of glaucoma in the setting of corneal transplantation was performed and serves as the basis for this review. Preexisting glaucoma and aphakia are notable risk factors. Patients that are candidates for deep anterior lamellar keratoplasty may benefit from reduced rates of post-keratoplasty glaucoma. Although glaucoma also complicates eyes with Descemet stripping endothelial keratoplasty, the severity is less and the intraocular pressure is more easily controlled when compared to penetrating keratoplasty. Endothelial keratoplasty creates unique perioperative issues mostly related to management of anterior chamber air bubbles.
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Affiliation(s)
- Ramez I Haddadin
- Massachusetts Eye & Ear Infirmary, Ophthalmology, Cornea & Refractive Surgery Service, Harvard Medical School , Boston, Massachusetts , USA
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95
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Abstract
The Boston Keratoprosthesis has allowed for visual restoration in patients with corneal blindness; however, vitreoretinal complications remain a significant cause of ocular morbidity. Retroprosthetic membranes, infectious endophthalmitis, sterile vitritis, vitreous hemorrhage, vitreous opacities, retinal detachment, cystoid macular edema, choroidal detachments, retinal vascular occlusion, and epiretinal membrane have all been described, may require the intervention of a vitreoretinal specialist, and are reviewed herein. A strong familiarity with associated posterior segment complications is important to maximizing patient outcomes.
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Affiliation(s)
- Bobeck S Modjtahedi
- Retina Service, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School , Boston, Massachusetts , USA
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Xiang J, Sun J, Hong J, Wang W, Wei A, Le Q, Xu J. T-style keratoprosthesis based on surface-modified poly (2-hydroxyethyl methacrylate) hydrogel for cornea repairs. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2015; 50:274-85. [DOI: 10.1016/j.msec.2015.01.089] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/11/2014] [Accepted: 01/30/2015] [Indexed: 10/24/2022]
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97
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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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Lee WB, Shtein RM, Kaufman SC, Deng SX, Rosenblatt MI. Boston Keratoprosthesis: Outcomes and Complications: A Report by the American Academy of Ophthalmology. Ophthalmology 2015; 122:1504-11. [PMID: 25934510 DOI: 10.1016/j.ophtha.2015.03.025] [Citation(s) in RCA: 95] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To review the published literature on safety and outcomes of the Boston type I keratoprosthesis (BI-KPro) for the surgical treatment of corneal opacification not amenable to human cadaveric corneal transplantation. METHODS Searches of peer-reviewed literature were conducted in PubMed and the Cochrane Library in December 2012, July 2013, and January 2014 without date restrictions. The searches were limited to studies published in English and yielded 587 citations. The abstracts of these articles were reviewed, 48 articles were selected for possible clinical relevance, and 22 were determined to be relevant for the assessment objectives. Nine studies were rated as level II evidence and 13 studies were rated as level III evidence. Excluded were level III evidence, case reports, review articles, letters, editorials, and case series with fewer than 25 eyes. RESULTS In 9 articles, a best-corrected Snellen visual acuity (BCSVA) of 20/200 or better occurred in 45% to 89% of eyes. Five articles described a BCSVA of 20/50 or better in 43% to 69% of eyes, and 4 articles found a BCSVA of 20/40 or better in 11% to 39% of eyes. Retention rates of the BI-KPro ranged from 65% to 100%. Reasons for loss of vision after BI-KPro implantation most commonly included corneal melts resulting from exposure keratopathy, endophthalmitis, and infectious keratitis or corneal ulceration. The 2 most common complications after surgery were retroprosthetic membrane formation (range, 1.0%-65.0%; mean ± standard deviation [SD], 30.0±19.0%) and elevated intraocular pressure (range, 2.4%-64.0%; mean ± SD, 27.5±18.1%). The 2 most common posterior segment complications were endophthalmitis (range, 0%-12.5%; mean ± SD, 4.6±4.6%) and vitritis (range, 0%-14.5%; mean ± SD, 5.6±4.7%). CONCLUSIONS The reviewed articles on BI-KPro use suggest that the device improves vision in cases of severe corneal opacification that were not amenable to corneal transplantation using human cadaveric keratoplasty techniques. A number of severe anterior and posterior segment complications can develop as follow-up continues, making ongoing close observation paramount for patients undergoing this surgery. These complications include infection, device extrusion, and permanent vision loss.
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Affiliation(s)
- W Barry Lee
- Piedmont Hospital and Eye Consultants of Atlanta, Atlanta, Georgia
| | - Roni M Shtein
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Stephen C Kaufman
- Department of Ophthalmology, State University of New York -Downstate, Brooklyn and Manhattan, New York
| | - Sophie X Deng
- Jules Stein Eye Institute, University of California, Los Angeles, Los Angeles, California
| | - Mark I Rosenblatt
- Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois
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Avadhanam VS, Smith HE, Liu C. Keratoprostheses for corneal blindness: a review of contemporary devices. Clin Ophthalmol 2015; 9:697-720. [PMID: 25945031 PMCID: PMC4406263 DOI: 10.2147/opth.s27083] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
According to the World Health Organization, globally 4.9 million are blind due to corneal pathology. Corneal transplantation is successful and curative of the blindness for a majority of these cases. However, it is less successful in a number of diseases that produce corneal neovascularization, dry ocular surface and recurrent inflammation, or infections. A keratoprosthesis or KPro is the only alternative to restore vision when corneal graft is a doomed failure. Although a number of KPros have been proposed, only two devices, Boston type-1 KPro and osteo-odonto-KPro, have came to the fore. The former is totally synthetic and the latter is semi-biological in constitution. These two KPros have different surgical techniques and indications. Keratoprosthetic surgery is complex and should only be undertaken in specialized centers, where expertise, multidisciplinary teams, and resources are available. In this article, we briefly discuss some of the prominent historical KPros and contemporary devices.
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Affiliation(s)
- Venkata S Avadhanam
- Sussex Eye Hospital, Brighton, UK ; Brighton and Sussex Medical School, Brighton, UK
| | | | - Christopher Liu
- Sussex Eye Hospital, Brighton, UK ; Brighton and Sussex Medical School, Brighton, UK ; Tongdean Eye Clinic, Hove, UK
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100
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Abstract
PURPOSE The aim of this study was to investigate the medium-term outcomes after Boston type 1 keratoprosthesis surgery in patients with poor prognosis for standard keratoplasty. METHODS A prospective study of a case series was conducted at a university-based referral center from 2006 to 2013. Forty-two eyes of 40 patients with a minimum follow-up of 4 years were recruited. The main outcome measures included best spectacle-corrected visual acuity (BSCVA), keratoprosthesis retention, and complications. RESULTS The mean follow-up was 64.9 ± 15.2 months (range, 48-88 months). At 1 week, 90.5% had an improvement in BSCVA by ≥2 lines compared with that in preoperative BSCVA. The best-ever vision was reached by the end of 6 months. Nevertheless, 39.5% (15/38) could not maintain the improved vision. The major etiology of visual deterioration after initial gains was glaucoma (60%). The initial keratoprosthesis retention rate was 80.9%, corresponding to a failure rate of 4 per 100 eye-years or 0.04/eye-year. Autoimmune diagnosis was the independent risk factor for keratoprosthesis failure (hazard ratio, 5.68; 95% confidence interval, 1.41-22.85; P = 0.014). The common postoperative complications were glaucoma, retroprosthetic membrane, corneal melting, infectious keratitis, and endophthalmitis. CONCLUSIONS Boston type 1 keratoprosthesis is an alternative for patients who are not candidates for corneal transplants. However, there was a trend toward visual loss over time most commonly because of progressive glaucoma. Therefore, appropriate patient selection, lifelong follow-up, and early aggressive treatment of complications are recommended.
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