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Raiskup F, Herber R, Lenk J, Pillunat LE, Spoerl E. Crosslinking with UV-A and riboflavin in progressive keratoconus: From laboratory to clinical practice - Developments over 25 years. Prog Retin Eye Res 2024; 102:101276. [PMID: 38830532 DOI: 10.1016/j.preteyeres.2024.101276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/30/2024] [Accepted: 05/31/2024] [Indexed: 06/05/2024]
Abstract
Changes in the biomechanical and biochemical properties of the human cornea play an important role in the pathogenesis of ectatic diseases. A number of conditions in primarily acquired (keratoconus or pellucid marginal degeneration) or secondarily induced (iatrogenic keratectasia after refractive laser surgeries) ectatic disorders lead to decreased biomechanical stability. Corneal collagen cross-linking (CXL) represents a technique to slow or even halt the progression of ectatic pathologies. In this procedure, riboflavin is applied in combination with ultraviolet A radiation. This interaction induces the production of reactive oxygen species, which leads to the formation of additional covalent bonds between collagen molecules and subsequent biomechanical corneal strengthening. This procedure is so far the only method that partially interferes etiopathogenetically in the treatment of ectatic diseases that slows or stops the process of corneal destabilization, otherwise leading to the need for corneal transplantation. Besides, CXL process increases markedly resistance of collagenous matrix against digesting enzymes supporting its use in the treatment of corneal ulcers. Since the discovery of this therapeutic procedure and the first laboratory experiments, which confirmed the validity of this method, and the first clinical studies that proved the effectiveness and safety of the technique, it has been spread and adopted worldwide, even with further modifications. Making use of the Bunsen-Roscoe photochemical law it was possible to shorten the duration of this procedure in accelerated CXL and thus improve the clinical workflow and patient compliance while maintaining the efficacy and safety of the procedure. The indication spectrum of CXL can be further expanded by combining it with other vision-enhancing procedures such as individualized topographically-guided excimer ablation. Complementing both techniques will allow a patient with a biomechanically stable cornea to regularize it and improve visual acuity without the need for tissue transplantation, leading to a long-term improvement in quality of life.
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Affiliation(s)
- Frederik Raiskup
- Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany.
| | - Robert Herber
- Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Janine Lenk
- Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Lutz E Pillunat
- Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
| | - Eberhard Spoerl
- Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Fetscherstrasse 74, 01307, Dresden, Germany
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Cortina MS, Greiner MA, Kuo AN, Li JY, Miller DD, Shtein RM, Veldman PB, Yin J, Kim SJ, Shen JF. Safety and Efficacy of Epithelium-Off Corneal Collagen Cross-Linking for the Treatment of Corneal Ectasia: A Report by the American Academy of Ophthalmology. Ophthalmology 2024:S0161-6420(24)00282-3. [PMID: 38935041 DOI: 10.1016/j.ophtha.2024.05.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Accepted: 05/03/2024] [Indexed: 06/28/2024] Open
Abstract
PURPOSE To review the evidence on the safety and effectiveness of epithelium-off corneal collagen cross-linking (CXL) for the treatment of progressive corneal ectasia. METHODS A literature search of the PubMed database was most recently conducted in March 2024 with no date restrictions and limited to studies published in English. The search identified 359 citations that were reviewed in abstract form, and 43 of these were reviewed in full text. High-quality randomized clinical trials comparing epithelium-off CXL with conservative treatment in patients who have keratoconus (KCN) and post-refractive surgery ectasia were included. The panel deemed 6 articles to be of sufficient relevance for inclusion, and these were assessed for quality by the panel methodologist; 5 were rated level I, and 1 was rated level II. There were no level III studies. RESULTS This analysis includes 6 prospective, randomized controlled trials that evaluated the use of epithelium-off CXL to treat progressive KCN (5 studies) and post-laser refractive surgery ectasia (1 study), with a mean postoperative follow-up of 2.4 years (range, 1-5 years). All studies showed a decreased progression rate in treated patients compared with controls. Improvement in the maximum keratometry (Kmax) value, corrected distance visual acuity (CDVA), and uncorrected distance visual acuity (UDVA) was observed in the treatment groups compared with control groups. A decrease in corneal thickness was observed in both groups but was greater in the CXL group. Complications were rare. CONCLUSIONS Epithelium-off CXL is effective in reducing the progression of KCN and post-laser refractive surgery ectasia in most treated patients with an acceptable safety profile. FINANCIAL DISCLOSURE(S) Proprietary or commercial disclosure may be found after the references.
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Affiliation(s)
- Maria S Cortina
- Department of Ophthalmology and Visual Science, University of Illinois College of Medicine, Chicago, Illinois
| | - Mark A Greiner
- Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Anthony N Kuo
- Department of Ophthalmology, Duke University School of Medicine, Durham, North Carolina
| | - Jennifer Y Li
- UC Davis Eye Center, University of California, Davis, California
| | - Darby D Miller
- Department of Ophthalmology, Mayo Clinic, Jacksonville, Florida
| | - Roni M Shtein
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan
| | - Peter B Veldman
- Department of Ophthalmology & Visual Science, The University of Chicago, Chicago, Illinois
| | - Jia Yin
- Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Boston, Massachusetts
| | - Stephen J Kim
- Department of Ophthalmology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Joanne F Shen
- Department of Ophthalmology, Mayo Clinic, Scottsdale, Arizona
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Son HS, Nugent L, Wang J, Varadaraj V, Smith K, Bower KS, Mgboji G, Soiberman US, Srikumaran D. Factors Associated With Receipt of Crosslinking for Keratoconus. Cornea 2024; 43:214-220. [PMID: 37506367 PMCID: PMC10818004 DOI: 10.1097/ico.0000000000003353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 06/11/2023] [Indexed: 07/30/2023]
Abstract
PURPOSE The aim of this study was to identify factors associated with receipt of standard fluence epithelium-off crosslinking (CXL) for keratoconus (KCN). METHODS This retrospective, cross-sectional study reviewed electronic health records of treatment-naive patients with KCN seen at the Wilmer Eye Institute between January 2017 and September 2020. Tomographic data were derived from Pentacam (Oculus, Wetzlar, Germany) devices. Multivariable population-average model using generalized estimating equations adjusting for age, sex, race, national area deprivation index, vision correction method, and disease severity was used to identify factors associated with receipt of CXL. RESULTS From 583 patients with KCN, 97 (16.6%) underwent CXL for KCN. Patients who received CXL in at least 1 eye were significantly younger (mean 24.0 ± 7.8 years) than patients who had never undergone CXL (33.4 ± 9.3 years) ( P < 0.001). In multivariable analysis, Black patients had 63% lower odds of receiving CXL for KCN (OR: 0.37, 95% CI, 0.18-0.79) versus White patients, and older age was protective against receipt of CXL (OR: 0.89 per 1-year increase, 95% CI, 0.86-0.93). Comparison of characteristics by race demonstrated that Black patients presented with significantly worse vision, higher keratometric indices (K1, K2, and Kmax), and thinner corneal pachymetry at baseline versus White or Asian patients. CONCLUSIONS In this clinical cohort of patients with KCN from a tertiary referral center, Black patients were less likely to receive CXL presumably because of more advanced disease at presentation. Earlier active population screening may be indicated to identify and treat these patients before they become ineligible for treatment and develop irreversible vision loss. Such strategies may improve health equity in KCN management.
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Affiliation(s)
- Hyeck-Soo Son
- Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
- Department of Ophthalmology, University of Heidelberg, Heidelberg, Baden-Wuerttemberg, Germany
| | - Liam Nugent
- Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jiangxia Wang
- Department of Biostatistics, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA
| | - Varshini Varadaraj
- Johns Hopkins Disability Health Research Center, Johns Hopkins School of Nursing, Baltimore, MD, USA
| | - Kerry Smith
- Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - Kraig S. Bower
- Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - Glory Mgboji
- Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - Uri S. Soiberman
- Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
| | - Divya Srikumaran
- Wilmer Eye Institute, Johns Hopkins Medical Institutions, Baltimore, MD, USA
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Mathan JJ, Gokul A, Simkin SK, Meyer JJ, McGhee CNJ. Keratoconus in Down syndrome: Prevalence, risk factors, severity and corneal tomographic characteristics. Clin Exp Ophthalmol 2024; 52:22-30. [PMID: 37963802 DOI: 10.1111/ceo.14316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 08/17/2023] [Accepted: 10/22/2023] [Indexed: 11/16/2023]
Abstract
BACKGROUND This study investigated the prevalence, risk factors and severity of corneal tomographic features of keratoconus in Down syndrome (DS). Additionally, previous studies indicate anomalous corneal features in DS, without keratoconus, this study characterised corneal features in DS without keratoconus. METHODS This prospective observational study included participants with DS ≥10 years old. Keratoconus diagnosis, risk factors and corneal tomographic characteristics were recorded. Participants underwent slit-lamp biomicroscopy, Scheimpflug corneal tomography, corneal topography and autorefraction. A diagnosis of keratoconus (DS-KC), suspect keratoconus (DS-SK) and non-keratoconus (DS-NK) was made based on expert review of scans by three fellowship trained anterior segment ophthalmologists. Corneal tomography parameters from one eye of each participant were analysed. RESULTS Keratoconus affected 50 (26.3%) of 190 participants, diagnosed by corneal tomography, topography or slit-lamp signs. Corneal hydrops affected 14.0% of DS-KC participants. Eye rubbing was a significant risk factor for keratoconus (p = 0.036). 175 (92%) participants could undertake corneal tomography of which tomography assessment alone identified 47 (26.9%) DS-KC participants, 64 (36.6%) DS-SK participants and 64 (36.6%) DS-NK participants. Significant differences (p < 0.001) were identified when the DS-KC, DS-SK and DS-NK groups were compared in maximum keratometry and posterior elevation at the thinnest point respectively: median (interquartile range) 50.20 (10.30D), 47.60 (1.95D), 46.50 (2.40D); 24.0 (38.00 μm), 10.00 (13.75 μm), 8.00 (6.00 μm). The DS-SK and DS-NK cohorts had similar minimum pachymetry, however, had several significantly different parameters among which included greater maximum keratometry, posterior elevation at the thinnest point in the DS-SK group. CONCLUSIONS Keratoconus is common in DS. Keratoconus screening with corneal tomography is recommended for early detection.
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Affiliation(s)
- Joyce J Mathan
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Akilesh Gokul
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Samantha K Simkin
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Jay J Meyer
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
| | - Charles N J McGhee
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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Al-Atawi S, Alghamdi A, Alzahrani K. The Lifetime Expenditure in People with Keratoconus in Saudi Arabia. Vision (Basel) 2023; 7:52. [PMID: 37606498 PMCID: PMC10443371 DOI: 10.3390/vision7030052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 07/10/2023] [Accepted: 07/23/2023] [Indexed: 08/23/2023] Open
Abstract
AIM This study measured and evaluated the socioeconomic burden of people living with keratoconus in Saudi Arabia. METHODS This study employed a cross-sectional design, a Keratoconus Economic Burden Questionnaire, and a convenient sample of 89 keratoconus patients (58.4% male) drawn from multiple regions in Saudi Arabia. It was conducted using online surveys, and the data were analyzed using appropriate quantitative techniques. RESULTS The mean age and annual income of the participants were 33.24 (SD = 6.82) years and USD 9046.52 (SD = 16,866.48), respectively, with only 37% being employed for wages. Up to 94.4% needed glasses or contact lenses at least once a week, and 73.0% received care from optometrists. The condition forced 45.9% of the respondents to change careers or leisure activities, with a further 51.3% having to take time off work. The mean annual out-of-pocket expenses for buying and maintaining glasses or contact lenses, as well as traveling and accommodation for keratoconus-related treatment were USD 2341.76 (SD = 3053.09), with 48.32 incurring upwards of USD 3240 over the period. The treatment costs increased with disease duration, r(89) = 0.216, p < 0.05. Regression results showed that the existence of comorbid eye disease, changing glasses at least once a year, and wearing either glasses or contact lenses at least once a week individually had statistically significant negative effects on the total annual keratoconus treatment costs, while disease duration, utilization of optometrists, and taking time off had a statistically significant increase on the total cost (p < 0.05). CONCLUSION With a prevalence rate of 1 in 375, progressive debilitation, and the lifetime nature of the disease, keratoconus is a critical public health concern in Saudi Arabia. The resulting visual impairment and discomfort, as well as both direct and indirect economic burdens, have considerable impacts on the patient's quality of life.
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Affiliation(s)
- Saleha Al-Atawi
- Optometry Department, Faculty of Applied Medical Science, Al Baha University, Al Baha 4781, Saudi Arabia
| | - Ali Alghamdi
- Faculty of Medicine, Al Baha University, Al Baha 4781, Saudi Arabia
| | - Khaled Alzahrani
- Optometry Department, King Fahad Armed Hospital, Jeddah 23311, Saudi Arabia
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Raiskup F, Herber R, Lenk J, Ramm L, Wittig D, Pillunat LE, Spoerl E. Corneal Crosslinking With Riboflavin and UVA Light in Progressive Keratoconus: Fifteen-Year Results. Am J Ophthalmol 2023; 250:95-102. [PMID: 36736417 DOI: 10.1016/j.ajo.2023.01.022] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 01/18/2023] [Accepted: 01/19/2023] [Indexed: 02/04/2023]
Abstract
PURPOSE To analyze the 15-year results of corneal crosslinking (CXL) in progressive keratoconus. DESIGN Retrospective follow-up analysis of interventional study patients. METHODS This study included keratoconic eyes with progressive disease treated from 2001 to 2006 at the Department of Ophthalmology, Carl Gustav Carus University Hospital, TU Dresden, Germany. CXL was performed by applying riboflavin and ultraviolet A (UVA) light according to a standard protocol. The best-corrected distance visual acuity (BCVA), slitlamp examination, and corneal topography as well as corneal thickness values were recorded preoperatively and 15 years after the treatment. RESULTS A total of 42 eyes received a complete follow-up of 15 years. The mean age of the patients at baseline was 26.9 (95% CI: 25.0-28.8) years. The maximum keratometry was 61.6 (95% CI: 58.2 - 64.9) diopters (D) preoperatively and 55.1 (95% CI: 51.6-58.4) D postoperatively; the decrease was statistically significant (P < .001). The mean keratometry value changed from 50.3 (95% CI: 48.3-52.4) D to 47.5 (95% CI: 45.3-49.4) D (P < 0.001). Furthermore, the thinnest corneal thickness decreased statistically significantly by 40 (95% CI: 24-56) µm (P < .001). The BCVA improved statistically significantly from 0.4 to 0.2 logMAR after the treatment. Retreatment was needed in 14% of cases. Mild scarring of the superficial stromal corneal layers was observed in 36% of the eyes, and in 67% of them visual acuity was stable or even improved. CONCLUSIONS The CXL procedure proved to be an effective method in the treatment of keratoconic eyes in the progressive stage of the disease, and achieved long-term stabilization without the occurrence of serious complications or side effects.
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Affiliation(s)
- Frederik Raiskup
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany
| | - Robert Herber
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany.
| | - Janine Lenk
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany
| | - Lisa Ramm
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany
| | - Dierk Wittig
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany
| | - Lutz E Pillunat
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany
| | - Eberhard Spoerl
- From the Department of Ophthalmology, University Hospital Carl Gustav Carus, TU Dresden, Germany
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Polido J, Dos Xavier Santos Araújo ME, Alexander JG, Cabral T, Ambrósio R, Freitas D. Pediatric Crosslinking: Current Protocols and Approach. Ophthalmol Ther 2022; 11:983-999. [PMID: 35482230 PMCID: PMC9114245 DOI: 10.1007/s40123-022-00508-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 03/31/2022] [Indexed: 11/24/2022] Open
Abstract
Keratoconus (KC) is likely to be more aggressive in the pediatric population, with a higher risk of progression and visual loss. Several techniques have been proposed for corneal crosslinking (CXL) so far. The standard CXL (SCXL) technique, or the Dresden Protocol, originally developed by Wollensak et al., has been shown to be safe and effective in the pediatric KC group. With similar efficacy to the conventional method, the accelerated CXL (ACXL) protocols proposed a reduced UVA exposure time by increasing the intensity of UVA irradiation. Transepithelial CXL (TCXL), considered an "epithelium-on" method, emerged as a strategy to improve safety and reduce postoperative complications and discomfort. For thinner corneas, we can highlight the use of hypoosmolar riboflavin and new studies, such as contact lens-assisted CXL (CACXL), the epithelial-island CXL (EI-CXL), and the Sub400 protocol. In addition to the different protocols used, another factor that changes CXL results is the type of carrier used: dextran-based or hydroxypropyl methylcellulose-based (HPMC) riboflavin solutions. There are several ways to perform a CXL surgery, and it is still unclear which method is the safest and most effective in the pediatric group. This review of the literature in English, available in PubMed, provides an update on corneal CXL in the pediatric KC group, exploring the data on the techniques currently used and under investigation, including their advantages, efficacy, safety profiles, risks, and cost analyses.
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Affiliation(s)
- Júlia Polido
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), Rua Botucatu, 806, Vila Clementino, São Paulo, SP, CEP 04023-062, Brazil.
| | - Maria Emília Dos Xavier Santos Araújo
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), Rua Botucatu, 806, Vila Clementino, São Paulo, SP, CEP 04023-062, Brazil.,Department of Ophthalmology, HSPE/IAMSPE, São Paulo, SP, Brazil
| | - João G Alexander
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), Rua Botucatu, 806, Vila Clementino, São Paulo, SP, CEP 04023-062, Brazil
| | - Thiago Cabral
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), Rua Botucatu, 806, Vila Clementino, São Paulo, SP, CEP 04023-062, Brazil.,Department of Ophthalmology EBSERH, HUCAM/CCS-UFES, Federal University of Espírito Santo (UFES), Vitória, ES, Brazil
| | - Renato Ambrósio
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), Rua Botucatu, 806, Vila Clementino, São Paulo, SP, CEP 04023-062, Brazil.,Department of Ophthalmology, The Federal University of the State of Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Denise Freitas
- Department of Ophthalmology, Federal University of São Paulo (UNIFESP), Rua Botucatu, 806, Vila Clementino, São Paulo, SP, CEP 04023-062, Brazil
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Ang MJ, Darbinian JA, Hoskins EN, Holsclaw DS, Sudesh S, Chandra NS. The Safety Profile of FDA-Approved Epithelium-Off Corneal Cross-Linking in a US Community-Based Healthcare System. Clin Ophthalmol 2022; 16:1117-1125. [PMID: 35431539 PMCID: PMC9012302 DOI: 10.2147/opth.s359224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 03/15/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose To determine the occurrence of early post-operative complications following FDA-approved epithelium-off corneal cross-linking in the United States. Materials and Methods This multicenter, retrospective cohort study identified patients who underwent epithelium-off (epi-off) corneal cross-linking (CXL) for keratoconus and post-refractive keratectasia within the Kaiser Permanente Northern California healthcare system between 2016 and 2018. Post-operative complications including delayed epithelial healing, infection, and loss of visual acuity were recorded. Results The study included 878 eyes of 654 patients. The mean age was 27±9.4 years (range 7–71). Five hundred ninety-nine patients (91.6%) had keratoconus while 55 had post-refractive corneal ectasia (8.4%). Forty-seven eyes had prolonged follow-up because of the occurrence of complications in the early post-operative period. The respective rates of delayed epithelial healing, and keratitis were 3.9% (95% CI 2.7–5.3%), and 1.5% (95% CI 0.8–2.5%). Four approaches for management of delayed epithelial healing were compared; epithelium healing duration was the longest in the repeat bandage contact lens (BCL) group (23.8 days) and the shortest in the antibiotic ointment group (14.3 days), with statistically significant differences (p < 0.05) in the healing time between these 2 groups. Conclusion The concern for early clinical complications after epi-off CXL often leads to delayed CXL intervention and further keratoconus progression with increased economic burdens. A large retrospective review of 878 eyes found that FDA-approved epi-off CXL protocol appears to be safe with low occurrence rates of early post-operative complications. The recommended management for delayed epithelial healing is using antibiotic ophthalmic ointment.
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Affiliation(s)
- Michael J Ang
- Department of Ophthalmology, California Pacific Medical Center, San Francisco, CA, USA
| | - Jeanne A Darbinian
- Division of Research, Kaiser Permanente Northern California, Oakland, CA, USA
| | - Eliza N Hoskins
- Department of Ophthalmology, The Permanente Medical Group, Oakland, CA, USA
| | - Douglas S Holsclaw
- Department of Ophthalmology, The Permanente Medical Group, Oakland, CA, USA
| | - Sudha Sudesh
- Department of Ophthalmology, The Permanente Medical Group, Oakland, CA, USA
| | - Naveen S Chandra
- Department of Ophthalmology, The Permanente Medical Group, Oakland, CA, USA
- Correspondence: Naveen S Chandra, The Permanente Medical Group, 320 Lennon Lane, Walnut Creek, CA, 94598, 94598, Tel +1 925-906-2550, Fax +1 925-906-2332, Email
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9
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Adverse events after riboflavin/UV-A corneal cross-linking: a literature review. Int Ophthalmol 2021; 42:337-348. [PMID: 34448966 DOI: 10.1007/s10792-021-02019-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/12/2021] [Indexed: 10/20/2022]
Abstract
BACKGROUND Riboflavin/UV-A corneal cross-linking (CXL) for treating keratoconus and iatrogenic corneal ectasia has been well-established as first treatment option to stabilize corneal tissue biomechanical instability. Although the plethora of clinical studies has been published into the field, there is no systematic review assessing the type and frequency of adverse events after CXL. METHODS A systemic literature review on clinical safety and adverse events after CXL in patients with keratoconus and corneal ectasia was performed using PubMed. A literature search was performed for relevant peer-reviewed publications. The main outcome measures extracted from the articles were adverse events, endothelial cell density, corrected distance visual acuity and maximum simulated keratometry. RESULTS The most frequent adverse events after CXL were corneal haze and corneal edema, which were mild and transient. The severe adverse events were infrequent (cumulative incidence: < 1.3%) after CXL. The clinical benefits of CXL highly outweighed the risks for the treatment of keratoconus and corneal ectasia. CONCLUSIONS The severe adverse events with permanent sequelae are infrequent after CXL and all are associated with corneal de-epithelialization, such as infectious keratitis and corneal scarring.
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Simpson A, Brogan K, Ramaesh K, Lockington D. What are the costs, capacity, and clinical implications of 'waiting for documented progression' in young West of Scotland patients prior to collagen cross linking? Eye (Lond) 2021; 35:1808-1810. [PMID: 33627758 PMCID: PMC7903035 DOI: 10.1038/s41433-021-01444-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 12/10/2020] [Accepted: 01/27/2021] [Indexed: 01/28/2023] Open
Affiliation(s)
- Alasdair Simpson
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom
| | - Kerr Brogan
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom
| | - Kanna Ramaesh
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom
| | - David Lockington
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, United Kingdom.
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Ashfaq H, Maganti N, Ballouz D, Feng Y, Woodward MA. Procedures, Visits, and Procedure Costs in the Management of Microbial Keratitis. Cornea 2021; 40:472-476. [PMID: 33214415 PMCID: PMC8062275 DOI: 10.1097/ico.0000000000002534] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
PURPOSE To investigate the burden of procedures, visits, and procedure costs in the management of microbial keratitis (MK). METHODS Medical records of patients from an academic hospital outpatient facility between December 2013 and May 2018 were retrospectively reviewed. Patients were included if they were older than the age of 18 years, recruited for study of likely MK, and not concurrently undergoing treatment for other acute eye conditions. For procedural costs, Medicare data for billing were obtained using the Center for Medicare and Medicaid Services Physician Fee Lookup tool. RESULTS A total of 68 patients were included for analysis. Patients were on average 51.3 years (SD = 19.5), 55.9% women (n = 38), and 89.7% White (n = 61). Per person, the average number of procedures was 2.9 (SD = 4.2). The average number of visits was 13.9 (SD = 9.2) over an average of 26.9 weeks (SD = 24.3). Age (P < 0.0001), positive Gram stain (P = 0.03), and mixed Gram stain (P = 0.002) were positively associated with the number of procedures. Age (P = 0.0003), fungal keratitis (P = 0.02), and mixed Gram stain (P = 0.01) were positively associated with the number of visits. Race was inversely associated with the number of procedures (P = 0.045) and visits (0.03). Patients with bacterial keratitis were more likely to have amniotic membrane grafts (P = 0.01) and tarsorrhaphies (P = 0.03) than fungal patients. Across all procedures performed for the management of MK, the mean cost per patient was $1788.7 (SD = $3324.62). CONCLUSIONS Patients incur many procedural costs and attend many visits during the management of MK. These findings emphasize the importance of patient-provider communication for frequent follow-up care and the potential need to perform procedures for disease management.
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Affiliation(s)
- Hamza Ashfaq
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI
| | - Nenita Maganti
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI
- Feinberg School of Medicine, Northwestern University, Chicago, IL
| | - Dena Ballouz
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI
| | - Yilin Feng
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI
| | - Maria A. Woodward
- Department of Ophthalmology and Visual Sciences, W.K. Kellogg Eye Center, University of Michigan, Ann Arbor, MI
- Institute for Healthcare Policy and Innovation, University of Michigan, Ann Arbor, MI
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12
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Ng SM, Ren M, Lindsley KB, Hawkins BS, Kuo IC. Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus. Cochrane Database Syst Rev 2021; 3:CD013512. [PMID: 33765359 PMCID: PMC8094622 DOI: 10.1002/14651858.cd013512.pub2] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Keratoconus is the most common corneal dystrophy. It can cause loss of uncorrected and best-corrected visual acuity through ectasia (thinning) of the central or paracentral cornea, irregular corneal scarring, or corneal perforation. Disease onset usually occurs in the second to fourth decade of life, periods of peak educational attainment or career development. The condition is lifelong and sight-threatening. Corneal collagen crosslinking (CXL) using ultraviolet A (UVA) light applied to the cornea is the only treatment that has been shown to slow progression of disease. The original, more widely known technique involves application of UVA light to de-epithelialized cornea, to which a photosensitizer (riboflavin) is added topically throughout the irradiation process. Transepithelial CXL is a recently advocated alternative to the standard CXL procedure, in that the epithelium is kept intact during CXL. Retention of the epithelium offers the putative advantages of faster healing, less patient discomfort, faster visual rehabilitation, and less risk of corneal haze. OBJECTIVES To assess the short- and long-term effectiveness and safety of transepithelial CXL compared with epithelium-off CXL for progressive keratoconus. SEARCH METHODS To identify potentially eligible studies, we searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2020, Issue 1); Ovid MEDLINE; Embase.com; PubMed; Latin American and Caribbean Health Sciences Literature database (LILACS); ClinicalTrials.gov; and World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not impose any date or language restrictions. We last searched the electronic databases on 15 January 2020. SELECTION CRITERIA We included randomized controlled trials (RCTs) in which transepithelial CXL had been compared with epithelium-off CXL in participants with progressive keratoconus. DATA COLLECTION AND ANALYSIS We used standard Cochrane methodology. MAIN RESULTS We included 13 studies with 723 eyes of 578 participants enrolled; 13 to 119 participants were enrolled per study. Seven studies were conducted in Europe, three in the Middle East, and one each in India, Russia, and Turkey. Seven studies were parallel-group RCTs, one study was an RCT with a paired-eyes design, and five studies were RCTs in which both eyes of some or all participants were assigned to the same intervention. Eleven studies compared transepithelial CXL with epithelium-off CXL in participants with progressive keratoconus. There was no evidence of an important difference between intervention groups in maximum keratometry (denoted 'maximum K' or 'Kmax'; also known as steepest keratometry measurement) at 12 months or later (mean difference (MD) 0.99 diopters (D), 95% CI -0.11 to 2.09; 5 studies; 177 eyes; I2 = 41%; very low certainty evidence). Few studies described other outcomes of interest. The evidence is very uncertain that epithelium-off CXL may have a small (data from two studies were not pooled due to considerable heterogeneity (I2 = 92%)) or no effect on stabilization of progressive keratoconus compared with transepithelial CXL; comparison of the estimated proportions of eyes with decreases or increases of 2 or more diopters in maximum K at 12 months from one study with 61 eyes was RR 0.32 (95% CI 0.09 to 1.12) and RR (non-event) 0.86 (95% CI 0.74 to 1.00), respectively (very low certainty). We did not estimate an overall effect on corrected-distance visual acuity (CDVA) because substantial heterogeneity was detected (I2 = 70%). No study evaluated CDVA gain or loss of 10 or more letters on a logarithm of the minimum angle of resolution (logMAR) chart. Transepithelial CXL may result in little to no difference in CDVA at 12 months or beyond. Four studies reported that either no adverse events or no serious adverse events had been observed. Another study noted no change in endothelial cell count after either procedure. Moderate certainty evidence from 4 studies (221 eyes) found that epithelium-off CXL resulted in a slight increase in corneal haze or scarring when compared to transepithelial CXL (RR (non-event) 1.07, 95% CI 1.01 to 1.14). Three studies, one of which had three arms, compared outcomes among participants assigned to transepithelial CXL using iontophoresis versus those assigned to epithelium-off CXL. No conclusive evidence was found for either keratometry or visual acuity outcomes at 12 months or later after surgery. Low certainty evidence suggests that transepithelial CXL using iontophoresis results in no difference in logMAR CDVA (MD 0.00 letter, 95% CI -0.04 to 0.04; 2 studies; 51 eyes). Only one study examined gain or loss of 10 or more logMAR letters. In terms of adverse events, one case of subepithelial infiltrate was reported after transepithelial CXL with iontophoresis, whereas two cases of faint corneal scars and four cases of permanent haze were observed after epithelium-off CXL. Vogt's striae were found in one eye after each intervention. The certainty of the evidence was low or very low for the outcomes in this comparison due to imprecision of estimates for all outcomes and risk of bias in the studies from which data have been reported. AUTHORS' CONCLUSIONS Because of lack of precision, frequent indeterminate risk of bias due to inadequate reporting, and inconsistency in outcomes measured and reported among studies in this systematic review, it remains unknown whether transepithelial CXL, or any other approach, may confer an advantage over epithelium-off CXL for patients with progressive keratoconus with respect to further progression of keratoconus, visual acuity outcomes, and patient-reported outcomes (PROs). Arrest of the progression of keratoconus should be the primary outcome of interest in future trials of CXL, particularly when comparing the effectiveness of different approaches to CXL. Furthermore, methods of assessing and defining progressive keratoconus should be standardized. Trials with longer follow-up are required in order to assure that outcomes are measured after corneal wound-healing and stabilization of keratoconus. In addition, perioperative, intraoperative, and postoperative care should be standardized to permit meaningful comparisons of CXL methods. Methods to increase penetration of riboflavin through intact epithelium as well as delivery of increased dose of UVA may be needed to improve outcomes. PROs should be measured and reported. The visual significance of adverse outcomes, such as corneal haze, should be assessed and correlated with other outcomes, including PROs.
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Affiliation(s)
- Sueko M Ng
- Department of Ophthalmology, School of Medicine, University of Colorado, Aurora, CO, USA
| | - Mark Ren
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Kristina B Lindsley
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, Netherlands
| | - Barbara S Hawkins
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Irene C Kuo
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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13
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Diagnostic patterns in keratoconus. Cont Lens Anterior Eye 2020; 44:101333. [PMID: 32448765 DOI: 10.1016/j.clae.2020.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/07/2020] [Accepted: 05/07/2020] [Indexed: 11/21/2022]
Abstract
PURPOSE To investigate the current patterns of diagnosis and referral in keratoconus. METHODS A retrospective chart review was performed of patients who had recently been diagnosed with keratoconus and attended dedicated clinics at Antwerp University Hospital, Belgium and Maria Middelares General Hospital, Ghent, Belgium between June 2013 and February 2018. Exclusion criteria included longstanding keratoconus diagnosis, reduced cognitive capabilities and prior surgical procedures (corneal crosslinking, penetrating keratoplasty or any type of refractive surgery). RESULTS Three-hundred and ninety-nine patients (722 eyes) were included in this study. The mean age was 24.7 ± 6.5 years and the average maximal keratometry was 51 ± 5.2 D for the better eye and 58.4 ± 9.6 D for the worse eye. Upon diagnosis, 233 eyes (32.2 %) and 51 eyes (7.1 %) had a thinnest pachymetry <450 and <400 μm, respectively. At 6-month follow-up, 58 % of patients had been fitted with specialty contact lenses. During follow-up, 199 eyes (27.6 %) underwent corneal crosslinking. One patient underwent corneal graft surgery of his worse eye due to contact lens intolerance and insufficient visual acuity. CONCLUSION Despite advances in diagnostic tools, keratoconus is often diagnosed at a relatively late stage. Earlier detection of keratoconus would increase the overall clinical benefit of corneal crosslinking. Further research into screening strategies is required to develop cost-effective screening programs.
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Hatch W, El-Defrawy S, Ong Tone S, Stein R, Slomovic AR, Rootman DS, Rabinovitch T, Kranemann C, Chew HF, Chan CC, Bujak MC, Cohen A, Lebovic G, Jin Y, Singal N. Accelerated Corneal Cross-Linking: Efficacy, Risk of Progression, and Characteristics Affecting Outcomes. A Large, Single-Center Prospective Study. Am J Ophthalmol 2020; 213:76-87. [PMID: 31945333 DOI: 10.1016/j.ajo.2020.01.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 01/02/2020] [Accepted: 01/03/2020] [Indexed: 10/25/2022]
Abstract
PURPOSE We examined the efficacy and preoperative characteristics that affect outcomes of accelerated (9 mW/cm2 for 10 minutes) corneal cross-linking (CXL). DESIGN Prospective single-center observational cohort study. METHODS We enrolled 612 eyes of 391 subjects with progressive keratoconus (n = 589), pellucid marginal degeneration (n = 11), and laser in situ keratomileusis-induced ectasia (n = 12). We evaluated best spectacle-corrected visual acuity (BSCVA), topography, refraction, endothelial cell density, corneal thickness, haze, intraocular pressure, and visual function before and 12 months after the CXL procedure. We tabulated the proportion of those with progression of maximum keratometry (Kmax). We included participant's race, age, sex, and the presence of preoperative apical scarring and environmental allergies in a multivariable linear regression model to determine the effect of these characteristics on outcomes. RESULTS At 1 year there was no significant change in mean Kmax (n = 569). Progression of Kmax was higher in subgroups with a baseline Kmax >58 diopters (n = 191) and those 14-18 years of age (n = 53). Preoperative BSCVA, Kmax, refraction, corneal cylinder, coma, central corneal thickness, and vision function were statistically and clinically significant predictors of outcomes (P < .001). Preoperative apical scarring led to worsening haze (P = .0001), more astigmatism (P = .002), more central corneal thinning (P = .002), and was protective to the endothelium (P = .008). Race, age, and sex affected some outcomes. CONCLUSION Mean Kmax was stable at 1 year after accelerated CXL. Younger patients and those with a higher preoperative Kmax need to be monitored closely for progression. Preoperative BSCVA, topography, refraction, CCT, and apical scarring were significant predictors of outcomes.
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Kuo IC, Hawkins BS, Ren M, Lindsley KB. Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus. Hippokratia 2020. [DOI: 10.1002/14651858.cd013512] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Irene C Kuo
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine; Department of Ophthalmology; 4924 Campbell Blvd #100 Baltimore Maryland USA 21236
| | - Barbara S Hawkins
- The Johns Hopkins University School of Medicine; Wilmer Eye Institute; 550 North Broadway, 9th floor Baltimore Maryland USA 21205-2010
| | - Mark Ren
- The Johns Hopkins University School of Medicine; Wilmer Eye Institute; 550 North Broadway, 9th floor Baltimore Maryland USA 21205-2010
| | - Kristina B Lindsley
- IBM Watson Health; Life Sciences, Oncology, & Genomics; Baltimore Maryland USA
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Corneal crosslinking: Current protocols and clinical approach. J Cataract Refract Surg 2019; 45:1670-1679. [DOI: 10.1016/j.jcrs.2019.06.027] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 05/19/2019] [Accepted: 06/21/2019] [Indexed: 12/18/2022]
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17
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Lalgudi VG, Nischal KK. Pediatric corneal collagen cross-linking for keratoconus: not an experimental procedure. J AAPOS 2019; 23:63-65. [PMID: 30599204 DOI: 10.1016/j.jaapos.2018.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 12/12/2018] [Accepted: 12/15/2018] [Indexed: 10/27/2022]
Affiliation(s)
- Vaitheeswaran G Lalgudi
- UPMC Eye Center, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania; Narayana Nethralaya, Bangalore, India
| | - Ken K Nischal
- UPMC Eye Center, UPMC Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania; University of Pittsburgh, School of Medicine.
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18
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Sharif R, Bak-Nielsen S, Hjortdal J, Karamichos D. Pathogenesis of Keratoconus: The intriguing therapeutic potential of Prolactin-inducible protein. Prog Retin Eye Res 2018; 67:150-167. [PMID: 29758268 PMCID: PMC6235698 DOI: 10.1016/j.preteyeres.2018.05.002] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 04/25/2018] [Accepted: 05/08/2018] [Indexed: 12/15/2022]
Abstract
Keratoconus (KC) is the most common ectatic corneal disease, with clinical findings that include discomfort, visual disturbance and possible blindness if left untreated. KC affects approximately 1:400 to 1:2000 people worldwide, including both males and females. The aetiology and onset of KC remains a puzzle and as a result, the ability to treat or reverse the disease is hampered. Sex hormones are known to play a role in the maintenance of the structure and integrity of the human cornea. Hormone levels have been reported to alter corneal thickness, curvature, and sensitivity during different times of menstrual cycle. Surprisingly, the role of sex hormones in corneal diseases and KC has been largely neglected. Prolactin-induced protein, known to be regulated by sex hormones, is a new KC biomarker that has been recently proposed. Studies herein discuss the role of sex hormones as a control mechanism for KC onset and progression and evidence supporting the view that prolactin-induced protein is an important hormonally regulated biomarker in KC is discussed.
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Affiliation(s)
- Rabab Sharif
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, United States
| | - Sashia Bak-Nielsen
- Department of Ophthalmology, Aarhus University Hospital, Aarhus DK-8200, Denmark
| | - Jesper Hjortdal
- Department of Ophthalmology, Aarhus University Hospital, Aarhus DK-8200, Denmark
| | - Dimitrios Karamichos
- Department of Cell Biology, University of Oklahoma Health Sciences Center, 975 NE 10th Street, Oklahoma City, OK 73104, United States; Department of Ophthalmology/Dean McGee Eye Institute, University of Oklahoma Health Science Center, 608 Stanton L. Young Blvd, Oklahoma City, OK 73104, United States.
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Abstract
PURPOSE To comprehensively review the available published literature for cross-linking in the pediatric population. METHODS Review of the literature published in English in PubMed. RESULTS Two hundred ten publications were considered. One hundred fifteen were considered relevant to this review. CONCLUSIONS Studies of cross-linking in pediatric patients are sparse, with relatively short follow-up times, and mostly on small groups of patients. Treatment with cross-linking halts progression of keratoconus in the pediatric population, and early treatment seems to be cost-effective compared with later penetrating keratoplasty. Long-term effects and regression rates remain unclear, and further studies are needed in this population.
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Affiliation(s)
- Claudia Perez-Straziota
- Department of Ophthalmology, University of Southern California, Los Angeles, CA
- Cornea Eye Institute, Beverly Hills, CA
| | - Ronald N Gaster
- Cornea Eye Institute, Beverly Hills, CA
- Department of Ophthalmology, Gavin Herbert Eye Institute, University of California, Irvine, Irvine, CA
| | - Yaron S Rabinowitz
- Cornea Eye Institute, Beverly Hills, CA
- Ophthalmology Research, Cedars-Sinai Medical Center, Los Angeles, CA
- Department of Ophthalmology, Jules Stein Eye Institute, University of California Los Angeles, Los Angeles, CA
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