Corneal Cross-linking For Progressive Keratoconus Research Articles

Clinical, Anatomical, and Densitometric Changes following Dresden vs. Accelerated Corneal Cross-Linking in Progressive Keratoconus.

To compare clinical, anatomical, and densitometric changes following Dresden (DCXL) vs. accelerated (ACXL) corneal UVA cross-linking (CXL; Avedro KXL, Geuder, Heidelberg, Germany) in progressive keratoconus (KC). In this retrospective study, we analyzed 20 patients following DCXL (3 mW/cm², 30 min, 5.4 J/cm²) and 44 patients following ACXL (9 mW/cm², 10 min, 5.4 J/cm²) between January 2016 and February 2020. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), central corneal thickness (CCT), steepest keratometry (Kmax), keratoconus index (KI), thinnest pachymetry (Pthin), and corneal densitometry (CD) were measured before and 3, 6, 12, and 24 months after CXL. During the follow-up period, no changes in UCVA, BSCVA, Kmax, KI, or Pthin occurred. CCT significantly decreased 3 months after DCXL (p = 0.032) and ACXL (p = 0.006). At the 12- and 24-month follow-up, CCT remained decreased in the DCXL (p = 0.035, 0.036, respectively) but not in the ACXL group. At the 12-month follow-up, the reduction in CCT was significantly greater in DCXL compared to ACXL (p = 0.012). At the 3-, 6-, 12-, and 24-month follow-ups, we found a significant increase in the anterior stroma CD following DCXL (p = 0.019, 0.026, 0.049, 0.047, respectively) but not ACXL. The CD changes were localized in the central concentric zones (0.0 to 6.0 mm). No intra- or postoperative complications occurred. ACXL and DCXL effectively halted KC progression. ACXL proved to be a safe time-saving alternative to conventional DCXL. DCXL led to a reduction in CCT and an increment in the CD of the central anterior stroma during 24 months of follow-up.

Assessment of Corneal Cross-Linking Effect on Progressive Keratoconus by Using the ABCD Grading System.

The aim of this study was to assess changes in corneal parameters 6 months after corneal cross-linking for progressive keratoconus, using the ABCD system. This retrospective study was conducted at the King Khaled Eye Specialist Hospital (Riyadh, Saudi Arabia) between January 1 and July 30, 2022. This study included 16 eyes of 16 patients with keratoconus who underwent corneal cross-linking at the same hospital and were at least 18 years old. At least one preoperative (T0) and one postoperative examination was performed for each patient. Six months after the procedure (T1), patients underwent corneal tomography. The parameters A, B, C, and D were also evaluated. Other parameters monitored included maximal keratometry (Kmax) (K1 and K2), Belin/Ambrósio Enhanced Ectasia Display, and index vertical asymmetry. The progression of ectasia was identified by a consistent change in at least two parameters: steepening of the anterior corneal surface or the posterior corneal surface, thinning or an increase in the rate at which the corneal thickness changed from the periphery to the thinnest point, where the magnitude of the change was greater than the normal noise of the testing system. Among the patients, 68.8% were men. The patients' average age was 25.8±5 years. Throughout the 6-month postoperative follow-up, parameters A, B, and C exhibited substantial changes (P = 0.000 for parameters A, B, and C). Parameter A increased 6 months after surgery, whereas parameters B and C decreased. Preoperatively and 6 months after surgery, Kmax, K1, and Belin/Ambrosio-enhanced ectasia demonstrated substantial differences. However, parameter D, K2, and the average pachymetric progression index did not change significantly. Anterior and posterior corneal curvatures and corneal thickness profiles can be useful for monitoring the progression of keratoconus and the success of the corneal cross-linking operation.

Long-Term Outcomes After Corneal Cross-linking for Progressive Keratoconus and Corneal Ectasia: A 10-Year Follow-Up of the Pivotal Study.

To report on the topographic and visual outcomes 10 years after corneal cross-linking in patients with progressive keratoconus and corneal ectasia after refractive surgery. Cross-sectional cohort study of an original, prospective, randomized, clinical trial. Patients treated in a single center cornea and refractive surgery practice as part of the U.S. pivotal trials, which led to the Food and Drug Administration approval of corneal cross-linking, were recruited for a 10-year follow-up examination. LogMar lines (LL) of uncorrected visual acuity (UCVA) and best spectacle--corrected visual acuity (BSCVA), maximum keratometry, and thinnest pachymetry were evaluated. In addition, the Belin ABCD progression display was used to determine progression (95% confidence interval) of the anterior curvature, posterior curvature, and corneal thickness of each individual eye included. Nineteen eyes of 13 patients treated with standard cross-linking returned for a 10-year follow-up examination. Mean maximum keratometry changed from 58.2±12.0 diopters (D) to 58.3±10.1 D, thinnest pachymetry changed from 440.6±51.6 µm to 442.3±54.4 μm, UCVA changed from 0.79±0.42 LL to 0.86±0.46 LL, and BSCVA changed from 0.38±0.26 LL to 0.33±0.34 LL, 10 years after cross-linking. Individually, 68.5% of the entire cohort, 81.8% of keratoconus eyes, and 50% of eyes with corneal ectasia remained topographically stable 10 years after standard cross-linking. In the entire cohort, visual acuity and topography remained stable 10 years after cross-linking. Over the long-term, eyes with keratoconus seem to be more stable than those with corneal ectasia.

Clinical Results of Accelerated Iontophoresis-Assisted Epithelium-on Corneal Cross-linking for Progressive Keratoconus in Children.

To evaluate the clinical characteristics of pediatric patients with progression of keratoconus after accelerated iontophoresis-assisted epithelium-on corneal cross-linking (I-ON CXL) and to assess the efficacy and safety of re-treatment using accelerated epithelium-off CXL (epi-OFF CXL). Sixteen eyes of 16 patients (mean age: 14.6 ± 2.5 years) with keratoconus underwent I-ON CXL. The main outcome measures were uncorrected distance visual acuity, corrected distance visual acuity, maximum keratometry index (Kmax), minimum corneal thickness, elevation front and elevation back measured at the thinnest point, total higher order aberrations root main square (HOA RMS), coma RMS, and spherical aberration. An increment of Kmax greater than 1.00 diopter (D) and a decrease of greater than 20 µm in pachymetry were considered to determine the progression of keratoconus. Patients with progression of keratoconus after I-ON CXL were re-treated using an epi-OFF CXL protocol. Two years after I-ON CXL, 12 patients showed progression of keratoconus, whereas 4 patients were stable. There was significant worsening of Kmax (P = .04) and steepest keratometric reading (P = .01). Furthermore, a significant correlation was documented between progression of keratoconus and age (P = .02). These patients were re-treated using an epi-OFF protocol and after 2 years all patients were stable, and a statistically significant reduction of the mean Kmax (P = .007), HOA RMS (P = .05), and coma RMS (P = 05) was observed. I-ON CXL was ineffective in the treatment of pediatric keratoconus in younger children, whereas it had an efficacy of 2 years in older children. Re-treatment using epi-OFF CXL proved effective to halt progression of keratoconus after I-ON CXL failure. [J Pediatr Ophthalmol Strabismus. 2024;61(1):44-50.].

Efficacy, Safety, and Outcomes following Accelerated and Iontophoresis Corneal Crosslinking in Progressive Keratoconus.

To investigate the outcomes of accelerated (A-CXL) and iontophoresis (I-CXL) corneal crosslinking in a large retrospective cohort with progressive keratoconus. This retrospective observational cohort study included consecutive patients treated by A-CXL (9 mW/5.4 J/cm2) or I-CXL with a minimal follow-up of 12 months. Visual acuity, manifest refraction, topography, specular microscopy, and corneal optical coherence tomography (OCT) were evaluated at baseline and at the last visit. Progression was defined as an increase in the maximum topographic keratometry (Kmax) of 1D. 302 eyes of 241 patients with a mean age of 25.2 ± 7.5 years were included from 2012 to 2019: 231 and 71 eyes in the A-CXL and I-CXL groups, respectively. The mean follow-up was 27.2 ± 13.2 months (maximum: 85.7 months). Preoperatively, the mean Kmax was 51.8 ± 4.0D, with no differences between groups. Mean topographic measurements and spherical equivalent remained stable during the follow-up. At the last visit, CXL failure was reported in 60 eyes (19.9%): 40 (14.7%) versus 20 (28.2%) in A-CXL versus I-CXL, respectively, p = 0.005. The likelihood of progression after CXL was significantly higher following I-CXL: RR = 1.62, CI95 = [1.02 to 2.59], p = 0.04. Demarcation line presence at 1 month was positively correlated with higher efficacy of CXL, p = 0.03. No endothelial damage was reported, especially in 51 thin corneas (range = 342-399 µm). A-CXL seems more effective than I-CXL in stabilizing keratoconus; this is to be taken into account when a therapeutic indication is posed according to the aggressiveness of the keratoconus.

Interethnic differences in post-procedural outcomes of corneal crosslinking for progressive keratoconus: A longitudinal cohort study

Purpose To assess interethnic differences in the prevalence of keratoconus and identify interethnic differences in safety and efficacy of crosslinking. Methods Participants diagnosed with progressive keratoconus and that received crosslinking treatment between January 1st 2012 and October 31st 2019, were included in this study. Participants received 12 months follow-up at the tertiary ophthalmology treatment centre of the University Medical Centre Utrecht (Utrecht, The Netherlands). A questionnaire addressing ethnicity, consanguinity, and educational level was conducted. Thinnest pachymetry and maximum keratometry values were chosen as indices for disease progression. A mixed effect model was used to examine associations between ethnicity, baseline clinical parameters, and treatment efficacy. Fisher’s exact test was used to identify differences in post-operative complications. Results 467 eyes of 318 patients were identified and considered eligible for analysis. At baseline North African and South American subjects were relatively over-represented (χ2, P < 0.001). Compared to Europeans, no ethnicity showed a significantly different disease progression 12-months post-crosslinking (P > 0.05). The overall post-operative complications rate was 3.2% (n = 15). There was no statistically significant difference in the number of infiltrates, persistent stromal scars, re-crosslinking or corneal transplantation between the ethnic groups and the European reference group (All P > 0.05). Conclusion Despite the relative overrepresentation of non-European patients at our keratoconus treatment centre, this study reports no differences between Middle Eastern, North African, Sub-Saharan African, South American, Caribbean, Asian ethnic groups and a European reference group after crosslinking for progressive keratoconus in terms of complication rates, keratometry progression, or corneal thinning at 12-month follow-up.

Comparison of accelerated corneal cross-linking for progressive keratoconus in pediatric and adult age groups: One-year results

To compare one-year results of accelerated cross-linking (ACXL) treatment for progressive keratoconus in pediatric and adult age groups. The records of patients who had undergone the ACXL procedure (9mV/cm2, 10min) for progressive keratoconus were evaluated retrospectively. The patients were divided into 2 groups, with the pediatric group aged 17years or less and the adult group aged 18years or more, for the statistical analysis. Pre- and 12-month post- ACXL best-corrected visual acuity (BCVA), maximum keratometry (Kmax), sim K1, sim K2, corneal thickness at the thinnest point (thCT), and corneal astigmatism (CA) values of the patient groups were recorded. Thirty-two right eyes of 32 patients were included in the pediatric group, and 32 right eyes of 32 patients were included in the adult group. A significant improvement in BCVA and a significant decrease in thCT values were present in both groups 12months after the surgery compared to the preoperative period. The decrease in Kmax, sim K1 and sim K2 values compared to the preoperative period was significant in the adult group. When the two groups were compared after 12months, only the simK1 value was significantly lower in the adult group, and there was no significant difference between the other measurements. There is a slight tendency toward more flattening in the adult group 12months after ACXL treatment, but this is not statistically significant.

Corneal Crosslinking for Progressive Keratoconus and Corneal Ectasia: Summary of US Multicenter and Subgroup Clinical Trials

PurposeThe multicenter studies reviewed were designed to evaluate the safety and efficacy of corneal collagen crosslinking (CXL) for the treatment of progressive keratoconus and corneal ectasia after laser refractive surgery. The results of these studies led to approval by the United States Food and Drug Agency for both conditions in 2016. This paper reviews these studies, as well as single-center substudies investigating other aspects of crosslinking outcomes.MethodsAs part of prospective, randomized, controlled clinical trials, the treatment group received standard CXL, and the sham control group received only riboflavin ophthalmic solution. The primary efficacy criterion was maximum keratometry (Kmax) 1 year after CXL. Secondary outcomes were corrected distance visual acuity (CDVA) and uncorrected distance visual acuity (UDVA). Safety and adverse events were analyzed. In single-center substudies, corneal topography, ocular aberrations, corneal haze measurements, corneal thickness, corneal biomechanics, subjective visual function, and outcomes predictors were also investigated. This paper presents a general review of the design and outcomes of crosslinking in these studies.ResultsIn the crosslinking treatment group, Kmax flattened by 1.6 diopters (D) and 0.7 D in eyes with keratoconus and ectasia, respectively. In both studies, there was continued progression in the control group. The CDVA improved by an average of 5.7 logMAR letters (LL) in the keratoconus treatment group and by 5.0 LL in the ectasia group. In both studies, corneal haze was the most frequently reported crosslinking-related adverse finding. This was most prominent at 1 month and generally returned to baseline between 3 and 12 months. In general, corneal topography, ocular aberrations, and subjective visual function improved after crosslinking.ConclusionsIn the US multicenter trials, CXL was shown to be safe and effective in stabilizing Kmax, CDVA, and UDVA in eyes with progressive keratoconus or corneal ectasia.Translational RelevanceCorneal crosslinking was originally developed in the laboratory at the University of Dresden in the late 1990s. The combination of ultraviolet-A light and riboflavin was found to be the most effective of a number of different modalities tested to increase the biomechanical strength of the cornea. The clinical study design for the US multicenter clinical trials of crosslinking demonstrated the safety and effectiveness of this technique for treatment of progressive keratoconus and corneal ectasia, bringing this important advancement to patients in the United States.

Accelerated versus Standard Corneal Cross-linking for Progressive Keratoconus in Syria.

PurposeTo compare the outcomes of accelerated versus standard corneal cross-linking for the treatment of progressive keratoconus.Methods In this retrospective comparative study, 63 eyes of 40 patients with progressive keratoconus were divided into two groups; 27 eyes in group one were treated with an accelerated protocol (10 mW/cm, 9 min) and 36 eyes in group two were treated with the standard method (3 mW/cm, 30 min). Visual acuity, refraction, corneal topography, corneal tomography, and anterior and posterior corneal higher-order aberrations (HOAs) were assessed preoperatively and 18–30 months postoperatively.ResultsThe LogMAR uncorrected and corrected distance visual acuity values were improved in both groups postoperatively. However, the improvement was significantly higher in group one (P 0.05, all). The flattening in the anterior keratometry readings, flat K, steep K, and average K were significantly higher in group two (P 0.001, all). The maximum anterior keratometry (AKf) values significantly decreased in both groups, whereas the maximum posterior keratometry (AKb) values increased. The reduction in the minimum corneal thickness (ThKmin) was significantly greater (36.49um) in group two, compared to 10.85um in group one. There was a significant increase in the posterior average keratometry, and a significant decrease in the posterior astigmatism, along 3 mm meridian in S-CXL (P = 0.03, P = 0.008, respectively), while the corresponding values showed no statistical significance in group one (P 0.05). The anterior corneal trefoil was significantly reduced in group one (P = 0.002), whereas anterior total HOAs and coma were significantly improved in group two (P 0.0014, all). The posterior corneal spherical aberration decreased significantly in group one (P = 0.02), while group two revealed significant reduction in the posterior trefoil values (P = 0.011). The change in the anterior maximum keratometry was significantly and positively correlated to the preoperative maximum keratometry in group two (P = 0.53, P = 0.003).ConclusionAn accelerated cross-linking protocol using 10 mW/cm for 9 min showed more visual improvement and less pachymetric reduction when compared to the standard protocol, however, anterior corneal flattening, posterior corneal steepening, and the change in the posterior astigmatism were significantly higher in the standard protocol; while corneal HOAs were improved in both protocols.

Nocardia keratitis following corneal cross linking for keratoconus

We report a case of Nocardia keratitis following corneal cross-linking for progressive keratoconus. A 26-year-old otherwise healthy woman underwent crosslinking for keratoconus in her left eye. She presented with corneal infiltrates with a wreath-like pattern, on the seventh postoperative day. Gram's and acid-fast staining revealed Nocardia. She was managed with topical fortified amikacin 2.5% eye drops. The keratitis resolved to leave dense vascularization which was managed with topical prednisolone 1% eye drops.

Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus.

Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus.

Visual and topographical outcomes following accelerated corneal crosslinking in progressive keratoconus

Visual and topographical outcomes following accelerated corneal crosslinking in progressive keratoconus

Corneal Cross-linking for Progressive Keratoconus: Up to 13 Years of Follow-up.

To assess the long-term efficacy and safety of epithelium-off corneal cross-linking according to the Dresden protocol (S-CXL) in progressive keratoconus. Patients treated with S-CXL from April 2006 to January 2010 at Humanitas Clinical and Research Center, Rozzano, Italy, who completed at least 10 years of follow-up were included. Corrected distance visual acuity (CDVA), refraction, and corneal topography and tomography with Pentacam (OCULUS Optikgeräte GmbH) were evaluated at baseline and 10+ years after the procedure. The definition of progression after S-CXL was two of the following three criteria: increase of "A" value, increase of "B" value, or decrease of minimum thickness evaluated with the ABCD progression display above 95% CI for the post-CXL population. Twenty-seven eyes of 22 patients were included. At a mean of 11 years of follow-up (maximum 13 years), S-CXL was able to maintain CDVA and induce significant regularization of the corneal surface as demonstrated by a significant decrease of the central keratoconus index (P = .035) and a decrease of anterior curvature ("A" value) starting from 2.54 ± 2.46, which reduced to 1.14 ± 1.60 (P = .005) at 10+ years of follow-up. Two of 27 eyes included showed significant progression after S-CXL (7.4%). S-CXL was confirmed to be a safe and effective treatment for progressive keratoconus with a failure rate of 7.4% at up to 13 years of follow-up. The authors suggest the use of a combined progression system that evaluates anterior and posterior curvature and with thickness map together with the knowledge of the noise level of the testing system. [J Refract Surg. 2020;36(12):838-843.].

Systemic supplemental oxygen therapy during accelerated corneal crosslinking for progressive keratoconus: randomized clinical trial.

To investigate the potential additive effect of systemic supplemental oxygen administered during accelerated corneal crosslinking (CXL) for progressive keratoconus (KC). Academic center. Randomized clinical trial. Eyes with progressive KC randomized to 3 different CXL protocols were included. The first group (OA-CXL) included 19 eyes that underwent an accelerated CXL protocol (9 mW/cm2 for 10 minutes) while receiving systemic oxygen at a rate of 5 L/min for 10 minutes. The second group consisted of 14 eyes undergoing the same accelerated CXL protocol without supplemental oxygen therapy (A-CXL). The third group (C-CXL) comprised 14 eyes undergoing conventional CXL according to the Dresden protocol. All subjects were followed up for at least 6 months. Visual acuity, keratometry and corneal biomechanical parameters including corneal hysteresis and corneal resistance factor (CRF) were measured preoperatively and 6 months postoperatively. Reduction in maximum keratometry (Kmax) was significantly greater in the OA-CXL group (P = .01). At baseline, the mean Kmax was 54.31 ± 3.64 diopters (D) in the OA-CXL group, 54.66 ± 4.99 D in the A-CXL group, and 56.03 ± 5.28 D in the C-CXL group (P = .58), which reached 53.58 ± 3.24 D, 54.59 ± 4.65 D, and 55.87 ± 4.73 D at 6 months in the 3 study groups, respectively (P = .115). The mean CRF increased significantly only in the OA-CXL group from a baseline value of 6.32 ± 2.12 mm Hg to 7.38 ± 1.88 mm Hg at 6 months (P = .009). This study suggests superior efficacy of an accelerated CXL protocol coupled with systemic oxygen supplementation when compared with the accelerated CXL protocol and the conventional protocol in eyes with progressive KC. In addition to greater reduction in Kmax as the primary outcome, improvement in corneal biomechanics was also observed at 6 months.

Efficacy and Safety of Accelerated Corneal Cross-linking for Progressive Keratoconus: A 5-Year Follow-up Study.

To investigate the long-term efficacy and safety of continuous light-accelerated corneal cross-linking (CXL) in patients with progressive keratoconus. This retrospective study analyzed 29 eyes of 29 consecutive patients with progressive keratoconus treated with epithelium-off riboflavin-ultraviolet induced accelerated CXL (30 mW/cm2-7.2 joules/cm2). Uncorrected (UDVA) and corrected (CDVA) distance visual acuity, keratometry measurements at 3 and 6 mm (Kmax, Kmin, and Kmean), topographic astigmatism, central corneal thickness, anterior corneal aberrometric analysis (at 3 and 6 mm), endothelial cell density, and central foveal thickness were evaluated before and 24 and 60 months after surgery. UDVA significantly improved at 60 months postoperatively (P = .028). Kmax and Kmean at 3 mm significantly decreased at 24 (P = .009 and .006, respectively) and 60 (P = .017 and .034, respectively) months postoperatively, whereas Kmin significantly decreased only at 24 months postoperatively (P = .032). Kmax at 6 mm significantly decreased at 24 and 60 months postoperatively (P = .035 and .027, respectively). Cylinder error significantly decreased at 24 and 60 months postoperatively (P = .001 and .023, respectively). Wavefront aberration variables remained unchanged after surgery, except for spherical aberration at 6 mm that decreased at 24 and 60 months postoperatively (P = .038 and .031, respectively) and trefoil at 0° that significantly decreased at 24 months postoperatively (P < .005). Endothelial cell density and central foveal thickness showed no changes from baseline. Accelerated CXL was found to be effective in halting keratoconus progression and improving some of the visual, topographic, and wavefront aberration variables evaluated. High energy irradiance did not induce significant changes in corneal transparency, endothelial cell density, and central foveal thickness. [J Refract Surg. 2020;36(11):724-730.].

Visual and Topographic Improvement with Epithelium-On, Oxygen-Supplemented, Customized Corneal Cross-Linking for Progressive Keratoconus.

Customized cross-linking has been proposed as an alternative to conventional cross-linking in patients with progressive keratoconus, targeting greater flattening of the cone region and improved visual function. Epithelium-on cross-linking aims to reduce complications associated with epithelial removal, while the addition of oxygen aims to maintain treatment effect. Our study evaluates the combination of these novel treatment strategies to achieve a minimally invasive treatment targeting maximal functional outcomes. This prospective study included 42 eyes undergoing epithelium-on, accelerated, oxygen-supplemented, customized corneal cross-linking for progressive keratoconus. Outcome measures, including refraction, visual acuity, and corneal tomography were obtained at baseline and at 1, 3, and 6 months, and 1 year postoperatively. Logarithm of the minimum angle of resolution (logMAR) uncorrected visual acuity was significantly improved, from 0.87 ± 0.53 preoperatively, to 0.78 ± 0.56 1 year postoperatively (Wilcoxon rank sum test, p = 0.016). LogMAR best spectacle-corrected visual acuity was also significantly improved, from 0.19 ± 0.36 preoperatively, to 0.11 ± 0.33 postoperatively (p = 0.004). Manifest refractive cylinder was significantly decreased, from 4.50 ± 2.96 D preoperatively, to 3.27 ± 2.61 D postoperatively (p = 0.004). The baseline maximum keratometry (Kmax) was 53.04 ± 7.91 D, significantly flattening to 52.25 ± 7.31 D by 1 month, and remaining relatively stable at 1 year postoperatively (52.31 ± 7.50 D) (p < 0.001). No significant adverse events occurred in any eye. Epithelium-on, accelerated, oxygen-supplemented, customized corneal cross-linking is a promising new treatment approach, with reduced maximum keratometry, reduced astigmatism, and improved visual acuity at 1 year, with a favorable safety and patient comfort profile.

Accelerated Pulsed High-Fluence Corneal Cross-Linking for Progressive Keratoconus

To report on 2-year results of accelerated corneal collagen cross-linking (CXL) in progressive ectasia using the Avedro KXL system. Prospective interventional case series. A total of 870 patients (1,192 eyes) attending Moorfields Eye Hospital after CXL were included. All patients undergoing CXL had progressive keratoconus. Corneas with a minimum stromal thickness <375μm were excluded. Riboflavin 0.1% soak duration was 10minutes. High-fluence pulsed UVA was delivered at 30 mW/cm2 for 4minutes, with a 1.5-second on/off cycle (total energy 7.2 J/cm2). Subjective refractive, corneal tomography, and specular microscopy were performed at baseline, 6, 12, and 24months postoperatively. The primary outcome measure was a change in maximum keratometry (Kmax) at 24months. Twelve- and 24-month follow-up data were available on 543 and 213 patients, respectively (mean age 25.4 ± 6.6 years). In mild cones (Kmax < 55 diopter [D]), mean keratometry remained unchanged at 24months. In more advanced disease, we observed modest corneal flattening compared to baseline (Kmax 63.2 ± 6.5 D vs 61.9 ± 8.1 D, P= .02), but no significant changes in central keratometry (K1 or K2). Keratometric stabilization was confirmed in 98.3% of eyes. Mean CDVA, manifest refraction and endothelial cell density did not change. Overall, 2.7% of eyes lost more than 2 lines of CDVA. Accelerated pulsed CXL is a safe, effective, and refractively neutral intervention (at 2 years) to halt disease progression in keratoconus.

Transepithelial versus epithelium-off corneal crosslinking for progressive keratoconus

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: The objective of this review is to assess the short‐term and long‐term effectiveness and safety of transepithelial CXL compared with epithelium‐off CXL for progressive keratoconus.

A randomised, controlled, observer-masked trial of corneal cross-linking for progressive keratoconus in children: the KERALINK protocol

IntroductionThe KERALINK trial tests the hypothesis that corneal cross-linking (CXL) treatment reduces the progression of keratoconus in comparison to standard care in patients under 17 years old. KERALINK is a...

Corneal Crosslinking in Progressive Keratoconus: Comparison of Dextran-Based and Hydroxypropyl Methylcellulose-Based Riboflavin Solutions Differences in demarcation line depth and 1 yaear outcomes

Keratoconus is a progressive ectatic disorder characterised by irregular myopic astigmatism and loss of visual acuity due to corneal thinning. Corneal collagen crosslinking is the treatment recognised to stop the progression of keratoconus. Our study evaluates and compares visibility and depth of the stromal demarcation line after corneal collagen crosslinking using anterior segment optical coherence tomography between two groups:crosslinking with dextran-based and hydroxypropyl methylcellulose-based riboflavin solutions. Our work proved a better visibility and a deeper demarcation line when we used HPMC-based riboflavin. Also the study revealed that HPMC-based riboflavin is associated with better biomechanical outcomes than dextran-based riboflavin.