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PURPOSE: To assess the long-term efficacy and safety of epithelium-off corneal cross-linking according to the standard (Dresden) protocol (S-CXL) in patients with progressive keratoconus older than 40 years. METHODS: Seventy-six eyes of 64 patients with a mean age of 46.4 ± 5.2 years were included. At baseline and after 6, 12, 24, 36, 48, 60, 72, 84, and more than 96 months (when available) after S-CXL, all patients were assessed with distance-corrected visual acuity (DCVA) and corneal topography and tomography with Pentacam HR (OCULUS Optikgeräte GmbH). A generalized linear model was used to compare the groups. Outcome measures were maximum keratometry, thinnest point, coma, spherical, and higher order aberrations, and ABC values. Fixed and random factors were age, gender, atopy, laterality, and group. RESULTS: The mean follow-up time was 62.1 ± 40.1 months (range: 12 to 144 months). The main outcome of the study was the evidence that S-CXL was able to safely stop the progression of keratoconus in all patients with none requiring repeat CXL. The generalized linear model analysis showed no significant change in DCVA over time ( P = 1.000), but atopy was negatively associated with DCVA ( P = .030, B = −0.69). The generalized linear model also showed that CXL was able to induce a significant flattening demonstrated as reduction of maximum keratometry ( P = .001, B = −0.35) and A value ( P =.001, B = −0.015) of the ABC display. Similarly, coma aberration was reduced over time ( P = .006, B = −0.005). CONCLUSIONS: S-CXL was confirmed to be a safe and effective treatment for progressive keratoconus even after the age of 40 years, inducing a significant flattening of the cone. [ J Refract Surg . 2021;37(5):338–342.]

PURPOSE To evaluate the correlation between changes in maximum keratometry (Kmax) and ABC values from the ABCD Progression Display (Pentacam) in progressive keratoconus (KC) and to evaluate whether the ABC changes were able to detect progression earlier than Kmax. SETTING Humanitas Clinical and Research Center, Rozzano, Milan, Italy. DESIGN Retrospective study. METHODS Kmax, ABC values, and thinnest point (ThCT) were recorded at the day of corneal crosslinking (CXL) (T0) and previous follow-up (T-1). In patients without earlier progression in Kmax, follow-up examination (T-2) was used to determine whether any of the ABC parameters reached statistical significance for progression. RESULTS Seventy-six eyes of 63 patients scheduled for CXL with documented progression (Kmax increase of >1.00 diopter) were included. There was a significant, albeit moderate, correlation between the change in Kmax between T0 and T-1 and the change in both A (ρ = 0.391) and B values (ρ = 0.339). There was no significant correlation between the change in Kmax between T0 and T-1 and the change in either C or ThCT. In patients with T-2 examinations, 16 (51.6%) of 31 patients showed a statistically significant change on the ABCD progression display that was not detected with Kmax. CONCLUSIONS This study showed a significant, but moderate, correlation between the change in Kmax and the change in A and B values in progressive KC. Moreover, more than half of the cases showed documented progression earlier with the ABCD progression display than that detected by standard Kmax changes. This study suggests possible changes in progression criteria to allow for earlier intervention.

PURPOSE: To assess the long-term efficacy and safety of epithelium-off corneal cross-linking according to the Dresden protocol (S-CXL) in progressive keratoconus. METHODS: 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. RESULTS: 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%). CONCLUSIONS: 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.]

Purpose. To evaluate the effectiveness of corneal cross-linking window absorption (CXL-WA) as an adjuvant therapy for Aspergillus keratitis. Methods. A 90-year-old male came to our clinic complaining of hyperemic conjunctivitis and progressive visual loss in the right eye. Slit-lamp examination showed keratic precipitates, severe corneal opacity, and stromal edema. Corneal scraping culture was positive for Aspergillus niger. Because the clinical condition did not sufficiently improve with antifungal therapy, the patient underwent CXL-WA as an adjuvant therapy. Results. During the first week after treatment, the Tyndall effect, corneal edema, and signs of ocular inflammation progressively lessened. At the third postoperative month, the cornea was stable without signs of fungal keratitis. However, after this period, a descemetocele appeared in the cornea (2 × 2 mm in diameter), so the patient underwent a corneal penetrating keratoplasty. Histological evaluation of the removed corneal tissue revealed the presence of hyphae and fungal infection. Conclusions. We reported a case of in vivo CXL-WA used as an adjuvant therapy for deep stromal Aspergillus keratitis. CXL did not completely eradicate the fungal infection which caused perforation 4 months after treatment and it still cannot be considered a definitive solution to mycotic keratitis, which maintains a poor long-term prognosis.

PURPOSE: To assess topographical changes in patients with keratoconus while awaiting corneal cross-linking (CXL) treatment. METHODS: In this prospective, double-center, observational clinical study, patients with keratoconus were enrolled. Progression was defined as a change in the curvature within the cone area of at least 1.00 diopter (D) on tangential map and a thinning of 20 μ m at the thinnest point after measurements taken at least 3 months apart. Morphological parameters were assessed at baseline (day of listing for CXL) and on the day of CXL treatment, including slit-lamp biomicroscopy, keratometry (maximum, minimum, and mean), and thinnest corneal thickness using corneal tomography (Pentacam; Oculus Optikgeräte GmbH, Wetzlar, Germany). RESULTS: One hundred four eyes of 104 patients were included. The waiting time was 84.8 ± 62.9 days. Twenty-five percent of patients showed evidence of progression while waiting for treatment. Patients who progressed while waiting for treatment were younger (22.2 ± 6.79 years) compared to those who did not show evidence of progression (25.4 ± 5.62 years) ( P = .02). Stratification by age groups showed a significant worsening of maximum keratometry of 1.18 ± 1.37 D in patients younger than 18 years compared to those 18 to 26 years of age and those older than 26 years ( P = .002 and .042, respectively). The multivariate model confirmed that the progression steepening of the maximum keratometry while waiting for treatment was associated with age ( P = .028). CONCLUSIONS: The results suggest that stratification of waiting time according to the patient's age is required to reduce the risk of further progression of keratoconus. [ J Refract Surg. 2018;34(3):177–180.]

PURPOSE: To compare the 2-year follow-up outcomes of three groups of patients with keratoconus treated with transepithelial iontophoresis (I-CXL), iontophoresis with epithelial removal (I-SCXL), and standard epithelium-off (S-CXL) CXL for progressive keratoconus. METHODS: Sixty eyes of 60 patients treated with CXL for progressive keratoconus were included in this comparative, prospective clinical study. Twenty patients were included in each group (I-CXL, I-SCXL, and S-CXL). Corrected distance visual acuity (CDVA), refraction, corneal topography, Scheimpflug tomography, and aberrometry were assessed at baseline and at 1, 3, 6, 12, and 24 months of follow-up. To assess the long-term safety and efficacy of these treatments, the preoperative values were compared with the values at 24 months of follow-up. RESULTS: The main outcome of the study was the non-statistically significant difference between the three protocols in induced change in most of the parameters, including visual acuity ( P = .665), topographic indexes (all P > .05), and maximum keratometry ( P = .611) after 2 years of follow-up. There were no significant differences in the change in refractive error following CXL in all groups or between groups (all P > .05). Conversely, I-CXL induced significantly less corneal thinning ( P = .0299 and .0121) and a significantly greater reduction of higher order aberrations and coma (all P < .0001) compared to S-CXL and I-SCXL. All protocols induced a significant increase in visual acuity (S-CXL P = .0004, I-SCXL P = .0045, and I-CXL P = .004). CONCLUSIONS: The 2-year results of this comparative, prospective clinical study demonstrate the efficacy and safety of I-CXL to treat progressive keratoconus and overcome the limitations of CXL with epithelial debridement. [ J Refract Surg . 2019;35(3):184–190.]

PURPOSE: To compare 1-year transepithelial corneal collagen cross-linking with iontophoresis (I-CXL) outcomes with standard CXL (S-CXL) epithelium-off for progressive keratoconus. METHODS: Forty eyes of 40 patients with progressive keratoconus were included in this comparative, prospective clinical study. Corrected distance visual acuity (CDVA), spherical equivalent, cylinder refraction, corneal topography, Scheimpflug tomography, aberrometry, and endothelial cell count were assessed at baseline and at 1, 3, 6, and 12 months of follow-up. RESULTS: Patients received either I-CXL (20 eyes) or S-CXL (20 eyes). Functional parameters (visual acuity and aberrometry) showed a significant improvement ( P < .05) after 6 and 12 months of follow-up in both groups. In the I-CXL group, the CDVA showed a rapid recovery of vision after 3 months ( P = .01) compared to baseline. Morphological parameters showed a significant reduction of maximum keratometry in the S-CXL group by −1.05 ± 1.51 diopters (D) after 12 months, whereas the I-CXL group curvature was stable (−0.31 ± 1.87 D). Minimum pachymetry values were stable even after 12 months of follow-up in the I-CXL group, whereas a significant corneal thinning 12 months following treatment was recorded in the S-CXL group ( P < .001). None of the patients had continuous progression of keratoconus or had to repeat CXL procedures. Endothelial cell counts did not change significantly ( P > .05). CONCLUSIONS: The 1-year outcomes suggest that I-CXL might be comparable to S-CXL in stabilizing the progression of the degenerative ectatic disease. Additionally, quicker improvement of functional parameters was reported in the I-CXL group. [ J Refract Surg. 2016;32(10):672–678.]

Purpose. To report the early outcomes of iontophoresis-assisted corneal collagen cross-linking procedure with epithelial debridement (I-SCXL).Methods. Twenty eyes of twenty patients with progressive keratoconus were included in this prospective clinical study. Best spectacle corrected visual acuity (BSCVA), sphere and cylinder refraction, corneal topography, Scheimpflug tomography, aberrometry, anterior segment optical coherence tomography (AS-OCT), and endothelial cell count were assessed at baseline and at 1, 3, and 6 months of follow-up. The parameters considered to establish keratoconus progression were always proven with differential maps as change in curvature in the cone area of at least 1 diopter obtained with an instantaneous map.Results. Functional parameters showed a significant improvement (p<0.05) of BSCVA after 3 and 6 months of follow-up. Morphological parameters indicated stabilization of the corneal ectasia during the follow-up; however, a positive trend was noted with a mean flattening of 1.73 D. Minimum pachymetry values showed thinning that remained constant after the treatment. The demarcation line was clearly visible in all patients, reaching a depth of308.2±37.74 μm. None of the patients had continuous progression of keratoconus or had to repeat cross-linking procedures. Endothelial cell counts did not change significantly (p>0.05).Conclusion. The early results indicate that the I-SCXL may be able to reduce the treatment time and improve the riboflavin diffusion.

To report refractive, topographic, tomographic, and aberrometric outcomes 12 months after corneal cross-linking (CXL) in eyes with progressive advanced keratoconus.Prospective, nonrandomized, single-center clinical study.Twenty-eight eyes undergoing CXL between April and June 2006.Riboflavin-ultraviolet A (UVA)-induced CXL included instillation of 0.1% riboflavin-20% dextrane solution 30 minutes before UVA irradiation and every 5 minutes for an additional 30 minutes during irradiation.Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), sphere and cylinder refraction, topography, tomography, aberrometry, and endothelial cell count were evaluated at baseline and at 1, 3, 6, and 12 months follow-up.Mean baseline UCVA and BSCVA were 0.17+/-0.09 and 0.52+/-0.17, respectively; 12-month mean UCVA and BSCVA were 0.27+/-0.08 and 0.72+/-0.16, a statistically significant difference (P0.05). Mean spherical equivalent refraction showed a significant decrease of 0.41 diopters (D). Mean baseline simulated keratometry (SIM K) flattest and steepest meridians and SIM K average were 46.10, 50.37, and 48.08 D, respectively; at 12 months, 40.22, 44.21, and 42.01 D, respectively, were recorded, a difference that was significant for all 3 indices (P0.05). Mean average pupillary power (APP) changed significantly from 47.50 to 41.04 D at 12 months (P0.05) and apical keratometry (AK) from 58.94 to 55.18 D (P0.05). The treated eyes showed no deterioration of the Klyce indices at 6 months postoperatively, whereas the untreated (contralateral) eyes did show deterioration. For a 3-mm pupil, there was a significant reduction (P0.05) in whole eye (total), corneal, higher order, and astigmatic wavefront aberrations. A significant difference (P0.05) in total coma and total spherical aberration after CXL was also observed. Mean baseline pupil center pachymetry and total corneal volume decreased significantly (P0.05) to 470.09+/-29.01 microm and 57.17+/-3.21 mm(3) from baseline values of 490.68+/-30.69 microm and 59.37+/-4.36 mm(3), respectively. Endothelial cell counts did not changed significantly (P=0.13).Corneal cross-linking seems to be effective in improving UCVA and BSCVA in eyes with progressive keratoconus by significantly reducing corneal APP, AK, and corneal and total wavefront aberrations at 1 year postoperatively.

PURPOSE: To report initial clinical results of transepithelial corneal collagen cross-linking with iontophoresis (I-CXL). METHODS: Twenty eyes of 20 patients diagnosed as having progressive keratoconus who underwent I-CXL were included in this prospective non-randomized clinical study. Corrected distance visual acuity (CDVA), spherical equivalent and cylinder refraction, various corneal topography and Scheimpflug tomography parameters, aberrometry, anterior segment optical coherence tomography, and endothelial cell count were assessed at baseline and at 1, 3, 6, and 12 months postoperatively. RESULTS: CDVA improved significantly at 3, 6, and 12 months postoperatively (logMAR difference of −0.07 ± 0.01, −0.09 ± 0.03, and −0.12 ± 0.06, respectively; P < .05). Aberrometry remained stable during follow-up and a trend toward improvement was noted. All topographic parameters (including maximum keratometry) were stable during the follow-up, but exhibited a positive non-significant trend toward improvement. Minimum corneal thickness values were stable for up to 12 months postoperatively. None of the patients showed a progression of keratoconus. Endothelial cell counts did not change significantly ( P > .05). CONCLUSIONS: Preliminary results up to 1 year postoperatively indicate the efficacy of I-CXL in stabilizing the progression of this degenerative disease combined with significant improvement of CDVA. I-CXL, which spares the corneal epithelium, has the potential to become a valid alternative for halting the progression of keratoconus while reducing postoperative patient pain, risk of infection, and treatment time in select patients; however, the relative efficacy of this technique compared to standard epithelium-off techniques remains to be determined. [ J Refract Surg . 2014;30(11):746–753.]

Aim: Limbal cultures restore the corneal epithelium in patients with ocular burns. We investigated the biological parameters instrumental for their clinical success. Methods: We report a long-term multicenter prospective study on 152 patients carrying corneal destruction due to severe ocular burns, treated with autologous limbal cells cultured on fibrin and clinical-grade 3T3-J2 feeder cells. Clinical results were statistically evaluated both by parametric and nonparametric methods. Results: Clinical outcomes were scored as full success, partial success and failure in 66.05, 19.14 and 14.81% of eyes, respectively. The total number of clonogenic cells, colony size, growth rate and presence of conjunctival cells could not predict clinical results. Instead, the clinical data provided conclusive evidence that graft quality and likelihood of a successful outcome rely on an accurate evaluation of the number of stem cells detected before transplantation as holoclones expressing high levels of the p63 transcription factor. No adverse effects related to the feeder layer have been observed and the regenerated epithelium was completely devoid of any 3T3-J2 contamination. Conclusion: Cultures of limbal stem cells can be safely used to successfully treat massive destruction of the human cornea. We emphasize the importance of a discipline for defining the suitability and the quality of cultured epithelial grafts, which are relevant to the future clinical use of any cultured cell type.

Purpose To evaluate the safety and efficacy of treatment of severe infectious corneal ulcers with hypoosmolar riboflavin solution and UV-A collagen cross-linking (CXL) without deepithelizing the cornea. Methods Four eyes of 3 patients with severe keratitis and associated corneal melting, were treated with a new protocol of corneal CXL for infectious keratitis, named cross-linking window absorption (CXL-WA). CXL-WA was performed when the infection did not respond to systemic and topical antibiotic therapy. The protocol entails the use of hypoosmolar riboflavin before the irradiation with UV-A, and the penetration is obtained through the epithelial defect overlying the ulcer. Results In all cases, CXL halted the progression of the ulcer. After a minimum follow-up of 3 months, none of the patients had recurrence of the infection. Conclusion CXL-WA is a promising technique of treatment of infectious corneal ulcers, delaying or preventing more invasive approaches.

Custom Phototherapeutic Keratectomy and Autologous Fibrin-cultured Limbal Stem Cell Autografting: A Combined Approach To the Editor: We report the effectiveness of combined custom phototherapeutic keratectomy (PTK) with intraoperative topography and fibrin-cultured limbal stem cell autografting to treat limbal destruction of the left eye of a 67-year-old man due to alkali burn, which occurred 12 years prior to presentation.

Purpose: To describe a new keratoplasty procedure using intraoperative topography to reduce postoperative astigmatism. Methods: One hundred sixty-five eyes of 150 consecutive patients were enrolled in this prospective study. The most common diagnosis was keratoconus (78.8%). As many as 5.5% had post‐laser in situ keratomileusis ectasia. Keratoplasty was performed with the Hanna Corneal Trephine System. A 24-bite running suture was placed, using a specially developed marker. Suture adjustment was performed with the aid of an intraoperative topographer (Keratron Scout; OPTIKON 2000, Rome, Italy). The aim of the adjustment was to obtain an astigmatism #2.0 D on the operating table. In case of .3.0 D of astigmatism at 1 month after surgery, suture adjustment was performed using the same intraoperative topographer. Results: At 12 months postoperatevely (suture in), data from 108 (64%) eyes were available. The mean refractive astigmatism was 3.53 D, and the mean topographical astigmatism was 4.7 D. At 18 months (suture out), data from 32 eyes (19.4%) were available, and at 24 months, data from 29 eyes (13.3%) were available. The mean refractive astigmatism was 3.39 D at 18 months and 3.47 D at 24 months. The mean topographic astigmatism was 2.30 D at 18 months and 1.76 D at 24 months. Mean best spectacle-corrected visual acuity (BSCVA) was 0.51 at 3 months, 0.63 at 12 months (suture in), 0.67 at 18 months (suture out), and 0.78 at 24 months postoperatively. Conclusions: The combination of intraoperative topography and a 24-bite single running suture resulted in a stable astigmatism throughout the follow-up period, even after suture removal. BSCVA reached a 20/40 level as early as 3 months postoperatively and continued to rise after suture removal. The stability of astigmatism and BSCVA shortened the postoperative visual rehabilitation time and provided a high quality of vision early in the postoperative period.