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Gustafsson I, Olafsdotttir T, Neumann O, Johansson P, Bizios D, Ivarsen A, Hjortdal JØ. Early findings in a randomised controlled trial on crosslinking protocols using isoosmolar and hypoosmolar riboflavin for the treatment of progressive keratoconus. Acta Ophthalmol 2024. [PMID: 38970233 DOI: 10.1111/aos.16736] [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: 02/27/2024] [Accepted: 06/22/2024] [Indexed: 07/08/2024]
Abstract
PURPOSE To present baseline characteristics and to present the perioperative corneal thickness during corneal crosslinking (CXL) treatment for progressive keratoconus and to describe how the addition of sterile water (SW) efficaciously can maintain the corneal thickness. The treatment efficacy will be evaluated when the 1-year follow-up is complete. METHODS A randomised clinical study using epithelium-off CXL with continuous UVA irradiation (9 mW/cm2) and two kinds of riboflavin solutions: (i) isoosmolar dextran-based riboflavin (n = 27) and (ii) hypoosmolar dextran-free riboflavin (n = 27). INCLUSION CRITERIA progressive keratoconus with an increase in maximum keratometry value (Kmax) of 1.0 dioptre (12 months) or 0.5 dioptres (6 months). Corneae thinner than 400 μm were also included. OUTCOME PARAMETERS Perioperative corneal thickness and the effect of adding SW. RESULTS Seventy-four per cent of the patients in the isoosmolar group and 15% in the hypoosmolar group required the addition of SW, which effectively maintained a corneal thickness of 400 μm in all cases during CXL. The addition of SW was primarily needed during the irradiation procedure and not the preoperative soaking period. CONCLUSIONS Especially during the CXL irradiation phase, isoosmolar riboflavin causes a significant dehydrating effect leading to corneal thinning during CXL. The customised addition of SW is efficacious in maintaining the corneal thickness during CXL and could increase the safety of the procedure.
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Affiliation(s)
- Ingemar Gustafsson
- Department of Ophthalmology, Skåne University Hospital, Malmö, Sweden
- Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Thorbjörg Olafsdotttir
- Department of Ophthalmology, Skåne University Hospital, Malmö, Sweden
- Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Olof Neumann
- Department of Ophthalmology, Skåne University Hospital, Malmö, Sweden
- Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Per Johansson
- Department of Ophthalmology, Skåne University Hospital, Malmö, Sweden
- Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Dimitrios Bizios
- Department of Ophthalmology, Skåne University Hospital, Malmö, Sweden
- Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Anders Ivarsen
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
| | - Jesper Ø Hjortdal
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
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Elving S, Fredriksson A, Beckman Rehnman J, Behndig A. Randomized clinical trial comparing customized corneal crosslinking: epi-on in high oxygen and epi-off in room air for keratoconus. J Cataract Refract Surg 2024; 50:746-753. [PMID: 38465837 DOI: 10.1097/j.jcrs.0000000000001442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 03/01/2024] [Indexed: 03/12/2024]
Abstract
PURPOSE To compare clinical outcomes of customized transepithelial (epi-on) corneal crosslinking (CXL) in high oxygen and customized CXL with epithelial removal (epi-off) in room air for keratoconus (KC). SETTING Umeå University Hospital, Umeå, Sweden. DESIGN Prospective, randomized, single-masked, intraindividually comparing study. METHODS 32 participants with bilateral progressive KC were treated with bilateral customized topography-guided CXL, 30 mW/cm 2 ; 7.2 to 15 J/cm 2 and were randomized to epi-on in one eye (32 eyes) and epi-off in the fellow eye (32 eyes). Uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA), maximal keratometry (Kmax), subjective ocular discomfort, low-contrast visual acuities (LCVAs) at 10% and 2.5% contrast, ocular and anterior corneal wavefront aberrations, manifest refractive spherical equivalent, endothelial cell count (ECC), and adverse events were assessed through 24 months. RESULTS Both treatments showed improvements at 24 months in UDVA; -0.16 ± 0.24 ( P < .001) and -0.13 ± 0.20 logMAR ( P = .006), respectively, CDVA; -0.10 ± 0.11 ( P < .001) and -0.10 ± 0.12 ( P = .001), Kmax; -1.74 ± 1.31 ( P < .001) and -1.72 ± 1.36 D ( P < .001). LCVA 10% improved for both protocols ( P < .001), but LCVA 2.5% improved for epi-on CXL only ( P = .001). ECC was unaltered, and no adverse events occurred. The epi-on eyes had significantly less discomfort symptoms during the whole first week posttreatment ( P < .05). CONCLUSIONS High-oxygen customized epi-on CXL is a viable alternative to room air customized epi-off CXL, with faster improvements in CDVA and LCVA and less early ocular discomfort.
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Affiliation(s)
- Sofie Elving
- From the Department of Clinical Sciences/Ophthalmology, Umeå University, Umeå, Sweden
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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.
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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
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Khanjian AT, Ivanova AV, Sklyarova AS, Khodzhabekyan NV, Manukyan IV. [Comparative analysis of clinical and functional parameters in patients with stable stage II-III keratoconus after implantation of corneal segments and fitting of scleral rigid contact lenses]. Vestn Oftalmol 2024; 140:72-77. [PMID: 38742501 DOI: 10.17116/oftalma202414002172] [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] [Indexed: 05/16/2024]
Abstract
The modern treatment strategy for keratoconus (KC) involves sequential application of medical technologies aimed at stabilizing pathological changes in the cornea and restoring visual acuity. PURPOSE This study compares the effect of implantation of intrastromal corneal ring segment (ICRS) and fitting of individual scleral rigid contact lenses (RCLs) on visual functions in patients with stage II-III KC after previously performed corneal collagen cross-linking. MATERIAL AND METHODS The Helmholtz National Medical Research Center of Eye Diseases examined and treated 34 patients (69 eyes) aged 18 to 33 years with stage II-III KC. The study included patients who had previously undergone standard corneal collagen cross-linking. Depending on the type of optical correction, the patients were divided into two groups: patients in group 1 underwent ICRS implantation using a femtosecond laser; patients in group 2 were fitted with individual scleral RCLs. RESULTS Improvement in clinical and functional parameters was observed in both groups. A higher clinical and functional result was achieved in group 2. CONCLUSION For patients with stable stage II-III KC, it is advisable to recommend fitting of individual scleral RCLs for visual rehabilitation.
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Affiliation(s)
- A T Khanjian
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - A V Ivanova
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - A S Sklyarova
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - N V Khodzhabekyan
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
| | - I V Manukyan
- Helmholtz National Medical Research Center of Eye Diseases, Moscow, Russia
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Naranjo A, Manche EE. A comprehensive review on corneal crosslinking. Taiwan J Ophthalmol 2024; 14:44-49. [PMID: 38654993 PMCID: PMC11034691 DOI: 10.4103/tjo.tjo-d-23-00055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 09/01/2023] [Indexed: 04/26/2024] Open
Abstract
Corneal crosslinking (CXL) represents a paradigm shift in the management of corneal ectatic disorders. Before CXL was introduced, patients would need specialty contact lenses and possible corneal transplantation. CXL involves a biochemical reaction in which ultraviolet A light is used in conjunction with Riboflavin to form crosslinks in between corneal stromal collagen. This leads to strengthening and stabilizing of the collagen lamellae, resulting in mechanical stiffening of the cornea. Multiple protocols have been proposed including epithelium on versus off and varying light intensity and duration of treatment. All protocols appear to be safe and effective with few reported complications including infection, stromal haze, scarring, and endothelial toxicity. Overall, CXL has demonstrated to halt the progression of the disease clinically and in keratometry readings and improve the quality of life for patients. It is a minimally invasive, cost-effective procedure that can be performed in an outpatient setting with a fast recovery time and long-lasting results.
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Affiliation(s)
- Andrea Naranjo
- Department of Ophthalmology, The Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
| | - Edward E. Manche
- Department of Ophthalmology, The Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California, USA
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Gustafsson I, Ivarsen A, Hjortdal J. Early findings in a prospective randomised study on three cross-linking treatment protocols: interruption of the iontophoresis treatment protocol. BMJ Open Ophthalmol 2023; 8:e001406. [PMID: 37739426 PMCID: PMC10533787 DOI: 10.1136/bmjophth-2023-001406] [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: 07/21/2023] [Accepted: 09/03/2023] [Indexed: 09/24/2023] Open
Abstract
PURPOSE To present the outcome of the interrupted iontophoresis-assisted treatment arm in an ongoing randomised clinical trial (NCT04427956). METHODS A randomised clinical study of corneal cross-linking (CXL) using continuous UV-A irradiation at a rate of 9 mW/cm2 and three different types of riboflavin and riboflavin delivery mode: (1) iso-osmolar dextran-based riboflavin (epithelium-off), (2) hypo-osmolar dextran-free riboflavin (epithelium-off) and (3) iontophoresis-assisted delivery of riboflavin (epithelium-on) for the treatment of progressive keratoconus. Inclusion criteria were an increase in the maximum keratometry value (Kmax) of 1.0 dioptre over 12 months or 0.5 dioptre over 6 months. The primary outcome in evaluating treatment efficacy was Kmax. Recently presented stratified detection limits were used post hoc to confirm the enrolment of patients with truly progressive keratoconus and in the assessment of the need for re-CXL. RESULTS Thirteen patients had been randomised to iontophoresis-assisted CXL when the treatment arm was interrupted; two patients dropped out. Of the remaining 11 patients, 7 were deemed as having truly progressive disease according to the more recent stratified detection limits. The disease continued to progress in three patients according to the original definition (increase in Kmax≥1 D), necessitating re-CXL with epithelium-off CXL. This progression was confirmed by post hoc analysis using the stratified detection limits for progression. CONCLUSIONS The iontophoresis-assisted CXL protocol failed to halt further disease progression in 27% of the patients. The failure rate increased to 38% when considering only the patients deemed to have truly progressive disease using the stratified detection limits.
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Affiliation(s)
- Ingemar Gustafsson
- Ophthalmology, Lund University, Lund, Sweden
- Ophthalmology, Skåne University Hospital Lund, Lund, Sweden
| | - Anders Ivarsen
- Ophthalmology, Aarhus University Hospital, Aarhus N, Denmark
| | - Jesper Hjortdal
- Ophthalmology, Aarhus University Hospital, Aarhus N, Denmark
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Gomes JAP, Azar DT, Baudouin C, Bitton E, Chen W, Hafezi F, Hamrah P, Hogg RE, Horwath-Winter J, Kontadakis GA, Mehta JS, Messmer EM, Perez VL, Zadok D, Willcox MDP. TFOS Lifestyle: Impact of elective medications and procedures on the ocular surface. Ocul Surf 2023; 29:331-385. [PMID: 37087043 DOI: 10.1016/j.jtos.2023.04.011] [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: 04/07/2023] [Accepted: 04/10/2023] [Indexed: 04/24/2023]
Abstract
The word "elective" refers to medications and procedures undertaken by choice or with a lower grade of prioritization. Patients usually use elective medications or undergo elective procedures to treat pathologic conditions or for cosmetic enhancement, impacting their lifestyle positively and, thus, improving their quality of life. However, those interventions can affect the homeostasis of the tear film and ocular surface. Consequently, they generate signs and symptoms that could impair the patient's quality of life. This report describes the impact of elective topical and systemic medications and procedures on the ocular surface and the underlying mechanisms. Moreover, elective procedures performed for ocular diseases, cosmetic enhancement, and non-ophthalmic interventions, such as radiotherapy and bariatric surgery, are discussed. The report also evaluates significant anatomical and biological consequences of non-urgent interventions to the ocular surface, such as neuropathic and neurotrophic keratopathies. Besides that, it provides an overview of the prophylaxis and management of pathological conditions resulting from the studied interventions and suggests areas for future research. The report also contains a systematic review investigating the quality of life among people who have undergone small incision lenticule extraction (SMILE). Overall, SMILE refractive surgery seems to cause more vision disturbances than LASIK in the first month post-surgery, but less dry eye symptoms in long-term follow up.
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Affiliation(s)
- José Alvaro P Gomes
- Dept. of Ophthalmology and Visual Sciences, Federal University of Sao Paulo/Paulista School of Medicine (UNIFESP/EPM), Sao Paulo, SP, Brazil.
| | - Dimitri T Azar
- University of Illinois College of Medicine, Chicago, IL, USA
| | - Christophe Baudouin
- Quinze-Vingts National Eye Hospital & Vision Institute, IHU FOReSIGHT, Paris, France
| | - Etty Bitton
- Ecole d'optométrie, Université de Montréal, Montréal, Canada
| | - Wei Chen
- Eye Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | | | - Pedram Hamrah
- Department of Ophthalmology, Tufts Medical Center, Tufts University School of Medicine, Boston, MA, USA
| | - Ruth E Hogg
- Centre for Public Health, School of Medicine, Dentistry and Biomedical Sciences, Belfast, UK
| | | | | | | | | | - Victor L Perez
- Foster Center for Ocular Immunology, Duke University Eye Center, Durham, NC, USA
| | - David Zadok
- Shaare Zedek Medical Center, Affiliated to the Hebrew University, School of Medicine, Jerusalem, Israel
| | - Mark D P Willcox
- School of Optometry and Vision Science, University of New South Wales, Sydney, Australia
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Lombardo M, Bernava GM, Serrao S, Roszkowska AM, Lombardo G. Predicting corneal cross-linking treatment efficacy with real-time assessment of corneal riboflavin concentration. J Cataract Refract Surg 2023; 49:635-641. [PMID: 36745847 DOI: 10.1097/j.jcrs.0000000000001163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 01/30/2023] [Indexed: 02/08/2023]
Abstract
PURPOSE To assess predictability of tissue biomechanical stiffening induced by UV-A light-mediated real-time assessment of riboflavin concentration during corneal crosslinking (CXL) of human donor tissues. SETTING Studio Italiano di Oftalmologia, Rome, Italy. DESIGN Laboratory study. METHODS 20 sclerocorneal tissues were randomly stratified to undergo CXL with either the epithelium intact (n = 12) or removed (n = 8). Samples underwent corneal soaking with 0.22% riboflavin formulation (RitSight) with dosing time of t = 10 minutes and t = 20 minutes in epithelium-off and epithelium-on protocols, respectively. All tissues underwent 9-minute UV-A irradiance at 10 mW/cm 2 using theranostic device (C4V CHROMO4VIS). The device used controlled UV-A light irradiation to induce both imaging and treatment of the cornea, providing a real-time measure of corneal riboflavin concentration and treatment efficacy (ie, theranostic score) during surgery. Tissue biomechanics were assessed with an air-puff device (Corvis), which was performed before and after treatment. A 3-element viscoelastic model was developed to fit the corneal deformation response to air-puff excitation and to calculate the mean corneal stiffness parameter (k c ). RESULTS Significant corneal tissue stiffening ( P < .05) was induced by the theranostic UV-A device in either CXL treatment protocol. Significant correlation was found between the theranostic score and the increase in k c ( R = 0.75; P = .003). The score showed high accuracy (94%) and precision (94%) to predict correctly samples that had improved tissue biomechanical strengthening. CONCLUSIONS Real-time assessment of corneal riboflavin concentration provided a predictive and precise approach for significant improvement of tissue strength on individual corneas, regardless of CXL treatment protocol.
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Affiliation(s)
- Marco Lombardo
- From the Studio Italiano di Oftalmologia, Rome, Italy (M. Lombardo, Serrao, G. Lombardo); Vision Engineering Italy srl, Rome, Italy (M. Lombardo); CNR-IPCF, Istituto per i Processi Chimico-Fisici, Messina, Italy (Bernava, G. Lombardo); Clinica Oculistica, Dipartimento di Scienze Biomediche, Università degli Studi di Messina, Messina, Italy (Roszkowska); Ophthalmology Department, Faculty of Medicine and Health Sciences, Andrzej Frycz Modrzewski Krakow University, Poland (Roszkowska)
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Gustafsson I, Bizios D, Ivarsen A, Hjortdal JØ. Patient experience and repeatability of measurements made with the Pentacam HR in patients with keratoconus. BMC Ophthalmol 2023; 23:201. [PMID: 37150816 PMCID: PMC10165742 DOI: 10.1186/s12886-023-02930-4] [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: 02/13/2023] [Accepted: 04/20/2023] [Indexed: 05/09/2023] Open
Abstract
BACKGROUND To investigate whether the repeatability of measurements with the Pentacam HR in patients with keratoconus is improved by patients gaining more experience of the measurement situation. Such an improvement could enhance the accuracy with which progressive keratoconus can be detected. METHODS Four replicate measurements were performed on Day 0 and on Day 3. Parameters commonly used in the diagnosis of progressive keratoconus were included in the analysis, namely the flattest central keratometry value (K1), the steepest central keratometry value (K2), the maximum keratometry value (Kmax), and the parameters A, B and C from the Belin ABCD Progression Display. In addition, quality parameters used by the Pentacam HR to assess the quality of the measurements were included, namely the analysed area (front + back), 3D (front + back), XY, Z, and eye movements. RESULTS Neither the diagnostic parameters nor the quality parameters showed any statistically significant improvement on Day 3 compared to Day 0. The quality parameter "eye movements" deteriorated significantly with increasing Kmax. CONCLUSION Gaining experience of the measurement situation did not increase the accuracy of the measurements. Further investigations should be performed to determine whether the increasing number of eye movements with increasing disease severity has a negative effect on the repeatability of the measurements.
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Affiliation(s)
- Ingemar Gustafsson
- Department of Ophthalmology, Skåne University Hospital, Department of Clinical Sciences, Lund University, Lund, Sweden.
| | - Dimitrios Bizios
- Department of Ophthalmology, Skåne University Hospital, Department of Clinical Sciences, Lund University, Lund, Sweden
| | - Anders Ivarsen
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
| | - Jesper Ø Hjortdal
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
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Gustafsson I, Vicente A, Bergström A, Stenevi U, Ivarsen A, Hjortdal JØ. Current clinical practice in corneal crosslinking for treatment of progressive keratoconus in four Nordic countries. Acta Ophthalmol 2023; 101:109-116. [PMID: 35811357 PMCID: PMC10084360 DOI: 10.1111/aos.15213] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Revised: 05/24/2022] [Accepted: 06/26/2022] [Indexed: 01/25/2023]
Abstract
PURPOSE To evaluate clinical practice in the diagnosis and treatment of progressive keratoconus with corneal crosslinking (CXL) in four Nordic countries. METHODS A questionnaire was sent to all centres at which keratoconus patients are evaluated and CXL is performed in Sweden, Denmark, Norway and Iceland. Nineteen of 20 centres participated. RESULTS CXL is performed approximately 1300 times per year in these four Nordic countries with a population of around 21.7 million (2019). In most cases, progression is evaluated using the Pentacam HR, and the maximum keratometry reading (Kmax ) is considered the most important parameter. The most frequently used treatment protocol in Scandinavia is the 9 mW/cm2 epi-off protocol, using hydroxylpropyl methylcellulose riboflavin (HPMC-riboflavin). The participants deemed the following areas to be in most need of improvement: adaptation of the CXL protocol to individual patients (5/19), the development of effective epi-on treatment protocols (4/19), optimal performance of CXL in thin corneas (4/19), improvement of the definition of progression (2/19), and diagnosis of the need for re-treatment (2/19). CONCLUSIONS We concluded that the diagnosis of progressive keratoconus and the diagnostic equipment used are similar. Treatment strategies are also similar but are suitably different to provide an interesting basis for the comparison of treatment outcomes. The high degree of participation in this survey indicates the possibility of future scientific collaboration on CXL focusing on the areas deemed to need improvement. It would also be of interest to evaluate the possibility of creating a Nordic CXL Registry. The high number of CXL treatments performed ensures sufficient statistical power to solve many questions. Such a registry could be an important contribution to evidence-based care and would allow for longitudinal evaluation.
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Affiliation(s)
- Ingemar Gustafsson
- Department of Clinical Sciences, Department of Ophthalmology, Lund University, Skåne University Hospital, Lund, Sweden
| | - André Vicente
- Department of Clinical Sciences, Department of Ophthalmology, Lund University, Skåne University Hospital, Lund, Sweden
| | - Anders Bergström
- Department of Clinical Sciences, Department of Ophthalmology, Lund University, Skåne University Hospital, Lund, Sweden
| | - Ulf Stenevi
- Department of Ophthalmology, Sahgrenska University Hospital, Mölndal, Sweden
| | - Anders Ivarsen
- Department of Ophthalmology, Aarhus University Hospital, Aarhus, Denmark
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Lombardo G, Bernava GM, Serrao S, Lombardo M. Theranostic-guided corneal cross-linking: Preclinical evidence on a new treatment paradigm for keratoconus. JOURNAL OF BIOPHOTONICS 2022; 15:e202200218. [PMID: 36059083 DOI: 10.1002/jbio.202200218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Revised: 08/31/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
Theranostics is an emerging therapeutic paradigm of personalized medicine; the term refers to the simultaneous integration of therapy and diagnostics. In this work, theranostic-guided corneal cross-linking was performed on 10 human sclero-corneal tissues. The samples were soaked with 0.22% riboflavin formulation and underwent 9 minutes UV-A irradiance at 10 mW/cm2 using theranostic device, which provided both a measure of corneal riboflavin concentration and a theranostic score estimating treatment efficacy in real time. A three-element viscoelastic model was developed to fit the deformation response of the cornea to air-puff excitation of dynamic tonometry and to calculate the mean corneal stiffness parameter before and after treatment. Significant correlation was found between the theranostic score and the increase in mean corneal stiffness (R = 0.80; P < .001). Accuracy and precision of the theranostic score in predicting the induced corneal tissue stiffening were both 90%. The riboflavin concentration prior to starting the UV-A photo-therapy phase was the most important variable to allow corneal cross-linking to be effective. Theranostic UV-A light mediated imaging and therapy enables the operator to adopt a precise approach for achieving highly predictable biomechanical strengthening on individual corneas.
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Affiliation(s)
- Giuseppe Lombardo
- CNR-IPCF, Istituto per i Processi Chimico-Fisici, Viale F, Messina, Italy
- Vision Engineering Italy srl, Rome, Italy
| | | | | | - Marco Lombardo
- Vision Engineering Italy srl, Rome, Italy
- Studio Italiano di Oftalmologia, Rome, Italy
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Seifert FK, Theuersbacher J, Schwabe D, Lamm O, Hillenkamp J, Kampik D. Long-Term Outcome of Corneal Collagen Crosslinking with Riboflavin and UV-A Irradiation for Keratoconus. Curr Eye Res 2022; 47:1472-1478. [PMID: 36173395 DOI: 10.1080/02713683.2022.2117383] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
PURPOSE To evaluate long-term outcomes of corneal collagen crosslinking (CXL) using riboflavin and UV-A irradiation and to determine when to repeat CXL. METHODS In this retrospective consecutive interventional case series 131 eyes of 131 patients (95 male, 36 female, mean age 29.7 ± 11.4 years) between 2006 and 2016 received standard CXL (Dresden protocol, epithelium-off) for progressive keratoconus. Corrected distance visual acuity (CDVA) and corneal tomography (K1, K2, Kmax) were repeatedly recorded 1 year (n = 103 eyes) to 10 years (n = 44) postoperatively. Only one eye per patient was included. Paired t-test or Wilcoxon matched-pairs signed rank test was used for parametric and nonparametric data, respectively. RESULTS 1-3 years preoperatively, median K2 significantly increased by 1.1 D (p < 0.001). Postoperatively, median K2 increased by 0.1 D after 1 year, then decreased over the remaining postoperative period by 0.85 D (p = 0.021). Kmax fluctuated without significant change. Median apical corneal thickness decreased by 16 µm (p = 0.012) after 5 years and then returned to preoperative values. Mean CDVA showed a significant improvement (decrease in logMAR 0.08 after 10 years, p = 0.010). CXL non-responders, defined by a postoperative increase in Kmax>2 D, increased from 16% after 5 to 33% after 10 years. Risk factors for non-response were young age, high astigmatism (>4.3 D), thin cornea (<480 µm), poor initial visual acuity (CDVA ≥0.3 D), and atopic dermatitis. 4 eyes were re-treated 3-4 years after first CXL without complications and keratoconus stabilized thereafter. CONCLUSIONS CXL can slow or stop keratoconus progression. However, as the number of responders declines after 5 years, especially patients with risk factors may require re-treatment.
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Affiliation(s)
- Franziska K Seifert
- Department of Ophthalmology, University Hospital Wuerzburg, Wuerzburg, Germany
| | | | - Dorothee Schwabe
- Department of Ophthalmology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Olga Lamm
- Department of Ophthalmology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Jost Hillenkamp
- Department of Ophthalmology, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Daniel Kampik
- Department of Ophthalmology, University Hospital Wuerzburg, Wuerzburg, Germany
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13
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Angelo L, Gokul Boptom A, McGhee C, Ziaei M. Corneal Crosslinking: Present and Future. Asia Pac J Ophthalmol (Phila) 2022; 11:441-452. [PMID: 36094381 DOI: 10.1097/apo.0000000000000557] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Accepted: 07/08/2022] [Indexed: 11/25/2022] Open
Abstract
Keratoconus is a progressive corneal thinning disorder that can lead to vision loss. In the last 2 decades, corneal crosslinking (CXL) has emerged as an effective method to halt the progression of keratoconus and reduce the number of patients requiring keratoplasty. The procedure has been adopted globally and has evolved to become a part of combination treatments to regularize the cornea and improve visual outcomes. CXL has even been extrapolated in managing other ocular pathologies such as progressive myopia, infectious keratitis, and bullous keratopathy. This review aims to summarize the current role of CXL in keratoconus and its alternative uses, and provide insights into future developments in this fast-developing field.
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Affiliation(s)
- Lize Angelo
- Department of Ophthalmology, New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand
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14
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Li Y, Lu Y, Du K, Yin Y, Hu T, Fu Y, Xiang A, Fu Q, Wu X, Wen D. Comparison of Efficacy and Safety Between Standard, Accelerated Epithelium-Off and Transepithelial Corneal Collagen Crosslinking in Pediatric Keratoconus: A Meta-Analysis. Front Med (Lausanne) 2022; 9:787167. [PMID: 35372437 PMCID: PMC8968048 DOI: 10.3389/fmed.2022.787167] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/15/2022] [Indexed: 01/10/2023] Open
Abstract
Purpose The purpose of the study is to compare the efficacy of standard epithelium-off CXL (SCXL), accelerated epithelium-off CXL (ACXL), and transepithelial crosslinking CXL (TECXL) for pediatric keratoconus. Methods A literature search on the efficacy of SCXL, ACXL, and TECXL [including accelerated TECXL (A-TECXL)] for keratoconus patients younger than 18 years was conducted using PubMed, Cochrane Library, ClinicalTrials.gov, and EMBASE up to 2021. Primary outcomes were changes in uncorrected visual acuity (UCVA) and maximum keratometry (Kmax) after CXL. Secondary outcomes were changes in best-corrected visual acuity (BCVA), mean refractive spherical equivalent (MRSE), and central corneal thickness (CCT). Estimations were analyzed by weighted mean difference (WMD) and 95% confidence interval (CI). Results A number of eleven identified studies enrolled 888 eyes (SCXL: 407 eyes; ACXL: 297 eyes; TECXL: 28 eyes; A-TECXL: 156 eyes). For pediatric keratoconus, except for a significant greater improvement in BCVA at 24-month follow-up in SCXL (WMD = –0.08, 95%CI: –0.14 to –0.01, p = 0.03, I2 = 71%), no significant difference was observed in other outcomes between the SCXL and ACXL groups. SCXL seems to provide greater changes in UCVA (WMD = –0.24, 95% CI: –0.34 to –0.13, p < 0.00001, I2 = 89%), BCVA (WMD = –0.09, 95% CI: –0.15 to –0.04, p = 0.0008, I2 = 94%), and Kmax (WMD = –1.93, 95% CI: –3.02 to –0.85, p = 0.0005, I2 = 0%) than A-TECXL, with higher incidence of adverse events. Conclusion For pediatric keratoconus, both SCXL and ACXL appear to be comparable in the efficacy of visual effects and keratometric outcomes; SCXL seems to provide greater changes in visual and pachymetric outcomes than A-TECXL.
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Affiliation(s)
- Yuanjun Li
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Ying Lu
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Kaixuan Du
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yewei Yin
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Tu Hu
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Yanyan Fu
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Aiqun Xiang
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Qiuman Fu
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Xiaoying Wu
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
| | - Dan Wen
- Eye Center of Xiangya Hospital, Hunan Key Laboratory of Ophthalmology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha, China
- *Correspondence: Dan Wen,
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