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Purpose: To validate and evaluate the use of a new biomechan-ical index known as the Corvis biomechanical index-laser vision correction (CBI-LVC) as a method for separating stable post-LVC eyes from post-LVC eyes with ectasia. Setting: 10 clinics from 9 countries. Design: Retrospective, multicenter, clinical study. Methods: The study was designed with 2 purposes: to develop the CBI-LVC, which combines dynamic corneal response (DCR) pa-rameters provided by a high-speed dynamic Scheimpflug camera (CorVis ST; OCULUS Optikgerate GmbH) and then to evaluate its ability to detect post-LVC ectasia. The CBI-LVC includes integrated inverse radius, applanation 1 (A1) velocity, A1 deflection amplitude, highest concavity and arclength, deformation amplitude ratio of 2 mm, and A1 arclength in millimeters. Logistic regression with Wald forward stepwise approach was used to identify the optimal com-bination of DCRs to create the CBI-LVC and then separate stable from LVC-induced ectasia. Eighty percentage of the database was used for training the software and 20% for validation. Results: 736 eyes of 736 patients were included (685 stable LVC and 51 post-LVC ectasia). The receiver operating char-acteristic curve analysis showed an area under the curve of 0.991 when applying CBI-LVC in the validation dataset and 0.998 in the training dataset. A cutoff of 0.2 was able to separate stable LVC from ectasia with a sensitivity of 93.3% and a specificity of 97.8%. Conclusions: The CBI-LVC was highly sensitive and specific in distinguishing stable from ectatic post-LVC eyes. Using CBI-LVC in routine practice, along with topography and tomography, can aid the early diagnosis of post-LVC ectasia and allow intervention prior to visually compromising progression.

Purpose: Spreading from China, COVID-19 pandemic reached Italy, the first massively involved western nation. At the beginning of March, 2020 in Northern Italy a complete lockdown of activities was imposed. Access to all healthcare providers, was halted for patients with elective problems. We present the management experience of the Humanitas Clinical and Research Center Ophthalmology Department in Rozzano, Milan, Italy, during the lockdown. Methods: Containment measures were taken to reduce viral transmission and identify infected patients. All planned visits were canceled but for those not deferrable. Social distancing was introduced reducing number of visits per hour. Minor surgery for progressive pathologies was continued. As the lockdown prolonged, we reorganized patient care. All canceled cases were evaluated by electronic medical records analysis and telephonic triage, to identify, recall, and visit patients at risk of vision loss. Results: From March 9, to April 30, 2020 we performed a total of 930 visits and 612 exams. Some visits ( n = 698) and exams ( n = 160) were deemed as necessary for continuity of care and performed as planned. Among the remaining 1283 canceled appointments, after evaluation 144 visits and 32 instrumental exams were classified as urgent and rapidly rescheduled. Performed surgical activities were limited to corneal collagen cross linking ( n = 39) and intravitreal injections ( n = 91), compared to 34 and 94, respectively, in the same period of 2019. Conclusion: In-office activities deemed not deferrable were performed safely. The recall service was highly appreciated by all patients. No patient or staff member reported symptoms of COVID-19.

Purpose: To report long-term clinical results of transepithelial cross-linking with iontophoresis (I-CXL) for progressive keratoconus (KC). Methods: Nineteen eyes of 19 patients treated with I-CXL for progressive keratoconus were included in this prospective clinical study. Preoperatively and in all available follow ups (6, 12, 24, 36, 48, 60, 72 and 84 months), the following parameters were measured. Corrected distance visual acuity (CDVA), spherical equivalent and cylinder refraction, corneal topography and aberrometry (Costruzione Strumenti Oftalmici (C.S.O.), Florence, Italy), Scheimpflug tomography (OCULUS Optikgeräte GmbH; Wetzlar, Germany). Definition of progression after I-CXL was 2/3 of the following criteria: increase of “A” value, increase of “B” value, decrease of minimal thickness evaluated with the ABCD progression display above 95% confidence interval for post-CXL population when compared to the scan 12 months post-op. Results: The mean follow-up time of included patients was 63 months (range 12 to 84 months, 5 patients reached 84 months). The general linear model showed no significant change over time in CDVA, Maximum Keratometry, Thinnest point, and A, B, C values of the Belin Progression Display (p > 0.05). Conversely, comatic and high order aberrations decreased significantly over time (both p =< 0.001). Five cases (26.31%) showed significant progression after a mean of 55 months (range 36–72) of follow up. Conclusion: Our study shows the ability of I-CXL to slow down KC progression in the majority of included patients, improving high order and comatic aberrations. A 26% progression rate was reported.

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.

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.

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.