1
|
Borchert GA, Kandel H, Watson SL. Epithelium-on versus epithelium-off corneal collagen crosslinking for keratoconus: a systematic review and meta-analysis. Graefes Arch Clin Exp Ophthalmol 2024; 262:1683-1692. [PMID: 37938377 PMCID: PMC11106102 DOI: 10.1007/s00417-023-06287-8] [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: 03/30/2023] [Revised: 09/10/2023] [Accepted: 10/21/2023] [Indexed: 11/09/2023] Open
Abstract
PURPOSE Corneal collagen crosslinking (CXL) is the primary treatment for progressive keratoconus which has a significant impact on vision and quality of life. Our study aimed to compare the efficacy and safety of epithelium-on versus epithelium-off CXL to treat keratoconus. METHODS We searched PubMed, Medline, Embase, Web of Science, and Scopus databases. We included studies that compared standard epithelium-off with epithelium-on CXL. The primary outcome measures were changes in corrected distance visual acuity (CDVA) and maximum keratometry (Kmax), and the secondary outcomes were uncorrected distance visual acuity (UDVA), central corneal thickness (CCT), and adverse events. A meta-analysis was performed on the primary and secondary outcomes based on the weighted mean differences between baseline to 12-month follow-up. RESULTS The search retrieved 887 publications with 27 included in the systematic review. A total of 1622 eyes (1399 patients; age 25.51 ± 4.02 years) were included in comparisons of epithelium-off to epithelium-on CXL in keratoconus. Epithelium-off CXL treated 800 eyes and epithelium-on CXL for 822 eyes. At 12-month follow-up, CDVA and Kmax showed no significant difference between the epithelium-off and epithelium-on CXL. The secondary outcomes showed that UDVA was better in epithelium-off CXL (- 0.11D, 95% CI - 0.12, - 0.1; p < 0.001) and there was more thinning in CCT in epithelium-off CXL (- 3.23 μm, 95% CI - 4.64, - 1.81; p <0.001). CONCLUSION Epithelium-off and epithelium-on CXL were both effective to treat progressive keratoconus. Further research is needed to compare the long-term outcomes and safety of both CXL protocols for adaptation into clinical practice.
Collapse
Affiliation(s)
- Grace A Borchert
- The University of Sydney, Save Sight Institute, Sydney, New South Wales, Australia.
| | - Himal Kandel
- The University of Sydney, Save Sight Institute, Sydney, New South Wales, Australia
| | - Stephanie L Watson
- The University of Sydney, Save Sight Institute, Sydney, New South Wales, Australia
| |
Collapse
|
2
|
Vilares-Morgado R, Ferreira AM, Cunha AM, Moreira R, Torrão L, Neves-Cardoso P, Pinheiro-Costa J. Transepithelial Accelerated Crosslinking for Progressive Keratoconus: A Critical Analysis of Medium-Term Treatment Outcomes. Clin Ophthalmol 2024; 18:393-407. [PMID: 38348140 PMCID: PMC10860395 DOI: 10.2147/opth.s450916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 01/24/2024] [Indexed: 02/15/2024] Open
Abstract
Purpose To report the 4-year outcomes of transepithelial accelerated corneal collagen crosslinking (TE-ACXL) in the treatment of eyes with progressive keratoconus (KC). Methods Eyes of patients who underwent TE-ACXL (6mW/cm2 for 15 minutes) for progressive KC and presented 48 months of follow-up were included. Corrected distance visual acuity (CDVA), keratometry measurements (Kmax, maximum keratometry, Kmean, mean keratometry and Astg, corneal astigmatism), thinnest corneal thickness (PachyMin), and topographic, and tomographic indices (specifically the posterior radius of curvature from the 3.0 mm centered on the thinnest point of the cornea (PRC), and the D-index) were analysed preoperatively and every 12 months after TE-ACXL, up to 48 months. Progression after TE-ACXL was considered when eyes presented ≥1 criteria: (1) increase of ≥1D in Kmax or increase of ≥0.75D in Kmean or increase of ≥1D in Astg; (2) reduction of ≥0.085 mm in PRC; (3) decrease ≥5% in PachyMin. Results 41 eyes from 30 patients were included, with a mean age at crosslinking of 20.90±4.69 years. There was a significant increase in Kmean (+0.64±1.04 D, p<0.001; +0.98 ± 1.49 D, p<0.001; +1.27±2.01 D, p<0.001; +1.13±2.00 D, p=0.006) and a significant decrease in PRC throughout follow-up (-0.12±0.22, p=0.002; -0.15±0.24, p<0.001; -0.17±0.43, p=0.021; -0.16±0.43, p=0.027). PachyMin decreased significantly at 36 and 48 months (-8.50±15.93 μm, p=0.004; -7.82±18.37, p=0.033). According to our progression criteria, there was a major progression rate throughout follow-up (57.1%, 61.1%, 58.8%, and 67.9%, respectively). Surgery and follow-up were uneventful in all subjects. Eleven eyes (26.8%) required further procedures, ≥36 months after the initial TE-ACXL, due to persistent progressive disease. Conclusion TE-ACXL proved to be a safe therapeutic option for progressive KC. However, its efficacy is deemed unsatisfactory, as a notable proportion of affected eyes may continue to advance within a 4-year timeframe, necessitating additional procedures to halt the disease's course.
Collapse
Affiliation(s)
- Rodrigo Vilares-Morgado
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - Ana Margarida Ferreira
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - Ana Maria Cunha
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - Raúl Moreira
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - Luís Torrão
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - Pedro Neves-Cardoso
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
| | - João Pinheiro-Costa
- Department of Ophthalmology, Centro Hospitalar Universitário de São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine of Porto University, Porto, Portugal
- Department of Biomedicine, Faculty of Medicine of Porto University, Porto, Portugal
| |
Collapse
|
3
|
Qin D, Han Y, Wang L, Yin H. Recent advances in medicinal compounds related to corneal crosslinking. Front Pharmacol 2023; 14:1232591. [PMID: 37841929 PMCID: PMC10570464 DOI: 10.3389/fphar.2023.1232591] [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] [Received: 05/31/2023] [Accepted: 09/21/2023] [Indexed: 10/17/2023] Open
Abstract
Corneal crosslinking (CXL) is the recognized technique to strengthen corneal collagen fibers through photodynamic reaction, aiming to halt progressive and irregular changes in corneal shape. CXL has greatly changed the treatment for keratoconus (KCN) since it was introduced in the late 1990's. Numerous improvements of CXL have been made during its developing course of more than 20 years. CXL involves quite a lot of materials, including crosslinking agents, enhancers, and supplements. A general summary of existing common crosslinking agents, enhancers, and supplements helps give a more comprehensive picture of CXL. Either innovative use of existing materials or research and development of new materials will further improve the safety, effectiveness, stability, and general applicability of CXL, and finally benefit the patients.
Collapse
Affiliation(s)
- Danyi Qin
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Eye Institute and Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Yi Han
- Fujian Provincial Key Laboratory of Ophthalmology and Visual Science, Eye Institute and Affiliated Xiamen Eye Center, School of Medicine, Xiamen University, Xiamen, Fujian, China
| | - Lixiang Wang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Hongbo Yin
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| |
Collapse
|
4
|
Singh M, Sinha BP, Mishra D, Deokar K, Bhatia G, Upreti G. Role of corneal collagen cross-linking in bullous keratopathy: A systematic review. Indian J Ophthalmol 2023; 71:1706-1717. [PMID: 37203022 PMCID: PMC10391445 DOI: 10.4103/ijo.ijo_1942_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023] Open
Abstract
Corneal cross-linking (CXL), a corneal strengthening procedure, is known to alter anterior stroma swelling behavior and is one of the treatment modalities of bullous keratopathy (BK). There are multiple studies published on the role of CXL in the treatment of BK. These articles had heterogeneous study population, different protocols used, and variable conclusions. This systematic review aimed to determine the role of CXL in the treatment of BK. The primary outcomes considered were changes in central corneal thickness (CCT) after 1, 3, and 6 months of CXL. The secondary outcome measures were changes in visual acuity, corneal clarity, subjective symptoms, and complications after CXL. We included randomized control trials (RCTs), observational and interventional studies, and case series with reports of more than 10 cases in this review. In RCTs, the mean pre-CXL CCT (794.0 ± 178.5 μm) in the intervention group (n = 37), decreased at 1 month (750.9 ± 154.3 μm) followed by a subsequent increase, but this difference was not significant during the 6-month follow-up (P- value 0.28, 0.82, and 0.82 at 1, 3, and 6 months, respectively). In noncomparative clinical studies (n = 188), the mean pre-CXL CCT (794.0 ± 178.5 μm) decreased at 1 month (710.9 ± 127.2 μm, P < 0.0001). Seven of the 11 articles included in the review reported no significant improvement in vision with CXL. The initial improvement in corneal clarity and clinical symptoms was not sustained. Current evidence suggests that CXL has short-term efficacy in the treatment of BK. More RCTs with high-quality evidence are needed.
Collapse
Affiliation(s)
- Mamta Singh
- Department of Ophthalmology, All India Institute of Medical Sciences, Rajkot, Gujarat, India
| | | | - Deepak Mishra
- Department of Ophthalmology, RIO, IMS, BHU, Varanasi, Uttar Pradesh, India
| | - Kunal Deokar
- Department of Pulmonary Medicine, All India Institute of Medical Sciences, Rajkot, Gujarat, India
| | - Gayatri Bhatia
- Department of Psychiatry, All India Institute of Medical Sciences, Rajkot, Gujarat, India
| | - Garima Upreti
- Department of Otorhinolaryngology, All India Institute of Medical Sciences, Rajkot, Gujarat, India
| |
Collapse
|
5
|
Hayes S, Morgan SR, Meek KM. Keratoconus: cross-linking the window of the eye. THERAPEUTIC ADVANCES IN RARE DISEASE 2021; 2:26330040211003573. [PMID: 37181107 PMCID: PMC10032441 DOI: 10.1177/26330040211003573] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 02/25/2021] [Indexed: 05/16/2023]
Abstract
Keratoconus is a condition in which the cornea progressively thins and weakens, leading to severe, irregular astigmatism and a significant reduction in quality of life. Although the precise cause of keratoconus is still not known, biochemical and structural studies indicate that overactive enzymes within the cornea break down the constituent proteins (collagen and proteoglycans) and cause the tissue to weaken. As the disease develops, collagen fibres slip past each other and are redistributed across the cornea, causing it to change shape. In recent years, it was discovered that the photochemical induction of cross-links within the corneal extracellular matrix, through the use of riboflavin and ultraviolet (UVA) light, could increase the strength and enzymatic resistance of the tissue and thereby halt keratoconus progression. Worldwide acceptance and use of riboflavin/UVA corneal cross-linking therapy for halting keratoconus progression has increased rapidly, in accordance with the growing body of evidence supporting its long-term effectiveness. This review focusses on the inception of riboflavin/UVA corneal cross-linking therapy for keratoconus, its clinical effectiveness and the latest scientific advances aimed at reducing patient treatment time, improving patient comfort and increasing patient eligibility for treatment. Plain language summary Review of current treatments using cross-linking to halt the progress of keratoconus Keratoconus is a disease in which the curved cornea, the transparent window at the front of the eye, weakens, bulges forward into a cone-shape and becomes thinner. This change of curvature means that light is not focussed onto the retina correctly and vision is progressively impaired. Traditionally, the effects of early keratoconus were alleviated by using glasses, specialist contact lenses, rings inserted into the cornea and in severe cases, by performing a corneal transplant. However, it was discovered that by inducing chemical bonds called cross-links within the cornea, the tissue could be strengthened and further thinning and shape changes prevented. The standard cross-linking procedure takes over an hour to perform and involves the removal of the cells at the front of the cornea, followed by the application of Vitamin B2 eye drops and low energy ultraviolet light (UVA) to create new cross-links within the tissue. Clinical trials have shown this standard procedure to be safe and effective at halting keratoconus progression. However, there are many treatment modifications currently under investigation that aim to reduce patient treatment time and increase comfort, such as accelerated cross-linking procedures and protocols that do not require removal of the surface cells. This review describes the different techniques being developed to carry out corneal cross-linking efficiently and painlessly, to halt keratoconus progression and avoid the need for expensive surgery.
Collapse
Affiliation(s)
- Sally Hayes
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Maindy Road, Cardiff, CF24 4HQ. UK
| | - Siân R Morgan
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| | - Keith M Meek
- Structural Biophysics Research Group, School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK
| |
Collapse
|
6
|
Nonlinear optical crosslinking (NLO CXL) for correcting refractive errors. Exp Eye Res 2020; 199:108199. [PMID: 32846150 DOI: 10.1016/j.exer.2020.108199] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/18/2020] [Accepted: 08/19/2020] [Indexed: 11/21/2022]
Abstract
Ultraviolet A (UVA) light-based photoactivation of riboflavin (Rf) to induce corneal crosslinking (CXL) and mechanical stiffening is now a well-known treatment for corneal ectasia and Keratoconus that is being used in a topographically guided photorefractive intrastromal CXL (PiXL) procedure to treat low degrees of refractive errors. Alternative approaches for non-invasive treatment of refractive errors have also been proposed that use femtosecond lasers (FS) that provide much faster, more precise, and safer results than UVA CXL. One such treatment, nonlinear optical crosslinking (NLO CXL), has been able to replicate the effects of UVA CXL, while producing a smaller area of cellular damage and requiring a shorter procedure time. Unlike UVA CXL, the treatment volume of NLO CXL only occurs within the focal volume of the laser, which can be placed at any depth and scanned into any pattern for true topographically guided refractive correction. This review presents our experience with using FS lasers to photoactivate Rf and perform highly controlled corneal CXL that leads to mechanical stiffening and changes in corneal shape.
Collapse
|
7
|
Cunha AM, Sardinha T, Torrão L, Moreira R, Falcão-Reis F, Pinheiro-Costa J. Transepithelial Accelerated Corneal Collagen Cross-Linking: Two-Year Results. Clin Ophthalmol 2020; 14:2329-2337. [PMID: 32884233 PMCID: PMC7434572 DOI: 10.2147/opth.s252940] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2020] [Accepted: 06/30/2020] [Indexed: 11/23/2022] Open
Abstract
PURPOSE To report 2-year outcomes of trans-epithelial accelerated corneal collagen crosslinking (TE-ACXL) procedure in the treatment of progressive keratoconus patients. PATIENTS AND METHODS Twenty-four eyes from 24 patients who underwent TE-ACXL (6mW/cm2 for 15 minutes) were included in this retrospective interventional study. Best-corrected visual acuity (BCVA), keratometry values, thinnest corneal thickness (PachyMin) and topometric indexes were analysed preoperatively and at 6-month, 12-month, 18-month and 24-month postoperative. Progression was assessed by increase ≥1.00D in maximum keratometry (Kmax); increase ≥1.00D in corneal astigmatism; decrease ≥2% in PachyMin; increase ≥0.42 in D-index. RESULTS There were no complications during or after TE-ACXL. No significant differences (Δ) were observed between baseline and 12-month or 24-month postoperative: ∆BCVA (-0.08 ± 0.25, p=0.190; -0.04 ± 0.17, p=0.588), ∆Kmax (-0.08 ± 1.32, p=0.792; -1.04 ± 1.89, p=0.135), ∆Astigmatism (-0.15 ± 0.89, p=0.485; -0.24 ± 1.38, p=0.609), ∆PachyMin (-0.56 ± 15.70, p=0.882; 0.56 ± 18.74, p=0.931), ∆Index Surface Variation (∆ISV) (-2.11 ± 10.27, p=0.395; -4.67 ± 17.32, p=0.442), ∆Index Vertical Asymmetry (∆IVA) (-0.05 ± 0.17, p=0.208; -0.08 ± 0.26, p=0.397), ∆Index Height Decentration (∆IHD) (0.00 ± 0.02, p=0.368; -0.01 ± 0.04, p=0.484), ∆KI (0.00 ± 0.05, p=0.851; 0.01 ± 0.06, p=0.877) and ∆D-index (0.15 ± 1.14, p=0.572; 0.06 ± 1.36, p=0.892). Eleven to 33% of patients had disease progression at 24-month postoperative according to the parameters used to determine progression. CONCLUSION Although some patients maintain disease progression, TE-ACXL seems to be a safe and effective treatment for keratoconus over the 2-year follow-up period. Studies with longer follow-up periods and larger patient cohorts are recommended.
Collapse
Affiliation(s)
- Ana Maria Cunha
- Department of Ophthalmology, Centro Hospitalar De São João, Porto, Portugal
| | - Tiago Sardinha
- Faculty of Medicine, University of Porto, Porto, Portugal
| | - Luís Torrão
- Department of Ophthalmology, Centro Hospitalar De São João, Porto, Portugal
| | - Raúl Moreira
- Department of Ophthalmology, Centro Hospitalar De São João, Porto, Portugal
| | - Fernando Falcão-Reis
- Department of Ophthalmology, Centro Hospitalar De São João, Porto, Portugal
- Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - João Pinheiro-Costa
- Department of Ophthalmology, Centro Hospitalar De São João, Porto, Portugal
- Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
| |
Collapse
|
8
|
Bradford S, Mikula E, Xie Y, Juhasz T, Brown DJ, Jester JV. Enhanced Transepithelial Riboflavin Delivery Using Femtosecond Laser-Machined Epithelial Microchannels. Transl Vis Sci Technol 2020; 9:1. [PMID: 32821498 PMCID: PMC7409279 DOI: 10.1167/tvst.9.6.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 02/29/2020] [Indexed: 12/20/2022] Open
Abstract
Purpose This study describes a femtosecond laser (FS) approach to machine corneal epithelial microchannels for enhancing riboflavin (Rf) penetration into the cornea prior to corneal crosslinking (CXL). Methods Using a 1030-nm FS laser with 5- to 10-µJ pulse energy, the corneal epithelium of slaughterhouse rabbit eyes was machined to create 2-µm-diameter by 25-µm-long microchannels at a density of 100 or 400 channels/mm2. Rf penetration through the microchannels was then determined by applying 1% Rf in phosphate-buffered saline for 30 minutes followed by removal of the cornea and extraction from the central stromal button. Stromal Rf concentrations were then compared to those obtained using standard epithelial debridement or 0.01% benzalkonium chloride (BAK) to disrupt the epithelial barrier. Results Microchannels formed using a 5-µJ/pulse at a density of 400 channels/mm2 achieved a stromal Rf concentration that was 50% of that achieved by removal of the corneal epithelium and imbibing with 1% Rf. Stromal Rf levels were also equal to that of debrided corneas soaked with 0.5% Rf, threefold higher than those soaked with 0.1% Rf, and twofold higher than corneas soaked in BAK without epithelial debridement. Organ culture of treated corneas showed a normal corneal epithelium following FS machining while BAK-treated corneas showed extensive epithelial and stromal damage at 24 hours posttreatment. Conclusions FS corneal epithelial machining can be used to enhance penetration of Rf into the stroma for corneal CXL. Translational Relevance The creation of epithelial microchannels allows for stromal Rf concentrations high enough to perform true transepithelial crosslinking.
Collapse
Affiliation(s)
- Samantha Bradford
- Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Eric Mikula
- Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Yilu Xie
- Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Tibor Juhasz
- Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - Donald J Brown
- Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| | - James V Jester
- Department of Ophthalmology and Biomedical Engineering, University of California, Irvine, Irvine, CA, USA
| |
Collapse
|
9
|
Valera-Cornejo DA, Vega-Estrada A, Alio JL. Invasive Pharmacology Outcomes with Different Corneal Cross-Linking Protocols: A Review. J Ocul Pharmacol Ther 2019; 35:475-490. [DOI: 10.1089/jop.2018.0144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Affiliation(s)
| | - Alfredo Vega-Estrada
- Miguel Hernandez University, Alicante, Spain
- VIssum Ophthalmic Corporation, Alicante, Spain
| | - Jorge L. Alio
- Miguel Hernandez University, Alicante, Spain
- VIssum Ophthalmic Corporation, Alicante, Spain
| |
Collapse
|
10
|
Madeira C, Vasques A, Beato J, Godinho G, Torrão L, Falcão M, Falcão-Reis F, Pinheiro-Costa J. Transepithelial accelerated versus conventional corneal collagen crosslinking in patients with keratoconus: a comparative study. Clin Ophthalmol 2019; 13:445-452. [PMID: 30880905 PMCID: PMC6402612 DOI: 10.2147/opth.s189183] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Purpose To systematically compare the efficacy of transepithelial accelerated corneal collagen crosslinking (TE-ACXL) with conventional corneal collagen crosslinking (C-CXL) in patients with progressive keratoconus. Methods Eyes of patients with progressive keratoconus who were treated with C-CXL (3 mW/cm2 for 30 minutes) were compared with those who underwent TE-ACXL (6 mW/cm2 for 15 minutes). Best-corrected visual acuity (BCVA), keratometry values, corneal thickness, and topometric indexes were compared before CXL, and at 2 months, 6 months, and 12 months postoperatively. Results The study enrolled 26 eyes of which 16 had TE-ACXL and 10 had C-CXL. Both groups were comparable at baseline and 12 months in terms of BCVA (P=0.16 and P=0.57), Kmax (maximum keratometry) (P=0.31 and P=0.73), pachymetry (P=0.75 and P=0.37), index of surface variance (ISV) (P=0.45 and P=0.86), index of vertical asymmetry (IVA) (P=0.26 and P=0.61), and index of height decentration (IHD) (P=0.27 and P=0.86, respectively). We did not observe significant differences between preoperative and 12-month postoperative readings in within-group analysis: ΔKmax (TE-ACXL, −2.13±5.41, P=0.25 vs C-CXL, 0.78±1.65, P=0.17), Δpachymetry (TE-ACXL, 4.10±14.83, P=0.41 vs C-CXL, −8.90±22.09, P=0.24), ΔISV (TE-ACXL, −8.50±21.26, P=0.24 vs C-CXL, 3.80±12.43, P=0.36), ΔIVA (TE-ACXL, −0.12±0.31, P=0.26 vs C-CXL, 0.03±0.18, P=0.61), and ΔIHD (TE-ACXL, −0.03±0.07, P=0.18 vs C-CXL, −0.01±0.03, P=0.88). Conclusion Both TE-ACXL and C-CXL were similarly effective. Further follow-up is required to determine whether these techniques are comparable in the long-term.
Collapse
Affiliation(s)
- Carolina Madeira
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal,
| | - Ana Vasques
- Faculty of Medicine, University of Porto, Porto, Portugal
| | - João Beato
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal,
| | - Gonçalo Godinho
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal,
| | - Luís Torrão
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal,
| | - Manuel Falcão
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal, .,Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Fernando Falcão-Reis
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal, .,Department of Surgery and Physiology, Faculty of Medicine, University of Porto, Porto, Portugal
| | - João Pinheiro-Costa
- Department of Ophthalmology, Centro Hospitalar de São João, Porto, Portugal, .,Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal
| |
Collapse
|