Epithelial and stromal remodelling following femtosecond laser–assisted stromal lenticule addition keratoplasty (SLAK) for keratoconus

The purpose of this study was to evaluate corneal epithelium and stromal remodelling with anterior segment optical coherence tomography in patients who have undergone stromal lenticule addition keratoplasty (SLAK) for advanced keratoconus. This was a prospective non-comparative observational study. Fifteen eyes of 15 patients with advanced keratoconus underwent implantation with a cadaveric, donor negative meniscus-shaped intrastromal lenticule, produced with a femtosecond laser, into a stromal pocket dissected in the recipient cornea at a depth of 120 μm. Simulated keratometry, central corneal thickness (CTT), corneal thinnest point (CTP), central epithelial thickness (CET), central and peripheral lenticule thickness, anterior and posterior stromal thickness were measured. Regional central corneal epithelial thickness (CET) and variations in the inner annular area (IAT) and outer annular area (OAT) were also analysed. All parameters were measured preoperatively and 1, 3, and 6 months postoperatively. The average anterior Sim-k decreased from 59.63 ± 7.58 preoperatively to 57.19 ± 6.33 D 6 months postoperatively. CCT, CTP, CET, and OAT increased and IAT decreased significantly after 1 month. All parameters appeared unchanged at 6-months except that of OAT that further increased. Lenticule thickness was stable. In conclusion we observed that SLAK reshapes the cornea by central flattening with stromal thickening and epithelial thickness restoration

Use of by-products of the olive oil industry for bread fortification: Effect of health claims on consumer liking

In this study the possibility to utilize by-products of the olive oil industry for bread fortification was investigated. In particular, when using a specific decanter made by Pieralisi (Italy) for olive oil extraction it is possible to obtain a by-product having the physical consistency of a pat\ue9, whose polyphenols content is very high [about 9600 ppm (f.w.)] and that could find an use in the food industry. After several tests at industrial level to identify the maximum allowable addition of pat\ue9 that would not cause technological problems in the production of a typical bread loaf, the dough fortification was carried out at 600 ppm. The cooking step caused a 14% polyphenols loss, but due to the water removal the final concentration in the bread was about 2600 ppm. The bread acceptability was then assessed in comparison with a traditional bread loaf using a panel of 110 consumers, giving no information about the bread characteristics. While the data showed higher preference of the traditional bread as far as color and general appearance, the fortified bread was preferred for taste and aroma. The test was then repeated giving the panelist information about the polyphenols content and their beneficial effects on the human health. In this case the fortified bread scored a higher acceptability vs the regular bread. The bread was also analyzed to assess the polyphenols bioavailability after baking and the results indicate that by eating 100 g of fortified bred the polyphenols daily intake would be about 4 times higher than the minimum quantity recommended by EFSA in order to exert a positive influence on consumers\u2019 health. The overall results indicate that fortification of bread with phenolic compounds resulting from the production of olive oil is feasible and that consumers are positively influenced in their choice by the information received

Accuracy of intraocular lens power calculation for cataract surgery after deep anterior lamellar keratoplasty

Background: The purpose of this study was to assess the accuracy of intraocular lens power (IOL) formulas for cataract surgery after deep anterior lamellar keratoplasty (DALK). Methods: This retrospective study included eyes which had previously undergone DALK and underwent standard phacoemulsification with monofocal IOL implantation between January 2012 and January 2021 at Ospedali Privati Forlì “Villa Igea” (Forlì, Italy). The predicted spherical equivalent (SE) was calculated using the Barrett Universal II, Emmetropia Verifying Optical (EVO), Haigis, Hoffer Q, Hoffer QST, Holladay 1, Holladay II, Kane and SRK/T formulas. Prediction error (PE) was calculated as the actual postoperative SE refraction minus the SE predicted refraction. Results: Eighty-two eyes of 82 patients were included. The mean PE was negative using all formulas. Friedman test revealed a statistically significant difference of the median absolute PE (MedAE) among the different IOL formulas (P = 0.005). On the basis of the MedAE, the formulas were ranked as follows: SRK/T (0.805 D), Kane (0.810 D), EVO (0.845 D), Hoffer QST (0.847 D), Barrett (0.895 D), Holladay 1 (0.915 D), Haigis (1.010 D) and Hoffer Q (1.070 D) formulas. Conclusions: All formulas had a tendency towards a myopic refractive shift in post-DALK eyes. Although the SRK/T, Kane, EVO and Hoffer QST formulas were more accurate, predictability of refractive outcomes was lower than in virgin eyes

In Vivo and Ex Vivo Evaluation of Inflammation and Apoptosis Induced after SMILE Procedures for Different Refractive Error Range

Abstract PURPOSE: To detect corneal inflammation and apoptosis induced after small incision lenticule extraction (SMILE) at different refractive corrections for moderate to high values of myopia. METHODS: Fifty patients (50 eyes) suffering from medium to high myopia (spherical equivalent refraction from -3.75 to -10.00 diopters (D) with refractive astigmatism under -0.75 D) underwent SMILE in order to correct myopic error. In vivo evaluation was done by corneal confocal microscopy (IVCM) and ex vivo by immunohistochemistry. After surgery, all corneal lenticules were checked for regularity, entirety, and fixed in formalin for immunohistochemistry evaluation of apoptosis (TUNEL) and inflammation (CD11b) levels. Postoperative assessments took place during the first week and the first and third months after surgery. Patients returned for IVCM examination for analysis of the corneal stromal femtosecond laser treatment interfaces reflectivity. RESULTS: No correlation was observed between treated myopic refractive error and number of CD11b+ and TUNEL+ cell in all analyzed extracted lenticules. IVCM at 1 week and 1 month of follow-up showed numerous reflective particles at the laser treatment interface with a moderate light scattering. In semi-quantitative analysis of reflectivity intensity at the laser interfaces, a statistical difference was evident only between 1 week and 1 month (p = 0.0213). CONCLUSIONS: SMILE, as an innovative all-femto surgical procedure, results in a reduced tissue inflammation and apoptosis levels with a minimum tissue response, in terms of interface reflectivity, and there are no statistically significant differences among variable treated refractive error range

Corneal cross-linking: intrastromal riboflavin concentration in iontophoresis-assisted imbibition versus traditional and transepithelial techniques

PURPOSE: To determine differences in riboflavin concentration in the anterior, intermediate, and posterior stroma after 3 corneal cross-linking imbibition techniques (standard epithelial [epi]-off, epi-on, and iontophoresis-assisted administration) of 0.1% riboflavin. DESIGN: Experimental laboratory investigation of human cadaver corneas not suitable for transplantation. METHODS: Ten corneas underwent imbibition with epi-on (n = 3), epi-off (n = 3), iontophoresis (n = 3), and saline exposure (control; n = 1). Femtosecond laser was used to produce 3 8-mm discs of the superficial (0-150 μm), intermediate (150-300 μm), and deep stroma (>300 μm). Riboflavin concentration was measured with high-performance liquid chromatography. The main outcome measure was riboflavin concentration at the 3 evaluated depths. RESULTS: The overall stromal concentration of riboflavin was 34.1 ± 7.1 μg/g in epi-off, 7.2 ± 3.7 μg/g in epi-on, and 15.0 ± 5.1 μg/g in iontophoresis. The mean riboflavin content in the superficial slice in the epi-off group was about 2-fold greater than that of the iontophoresis group (50.5 ± 5.3 μg/g and 23.6 ± 2.5 μg/g, respectively) and 4-fold greater than that of the epi-on group (11.7 ± 3.3 μg/g). Similar differences among the 3 groups were observed for the intermediate and posterior stromal slices, presenting an evident reduction of riboflavin concentration with increasing depth in all groups. Slice depth-dependent decrease in riboflavin concentration was statistically significant (general linear model (GLM); F1,6 = 62.265, P < .001), as was the group-dependent variation (GLM; F2,6 = 20.268, P = .002) and the slice depth group interaction (GLM; F2,6 = 18.004, P = .002). CONCLUSIONS: Corneal cross-linking transepithelial iontophoresis imbibition yielded greater and deeper riboflavin saturation with respect to conventional epi-on, while maintaining the advantages of avoiding epithelial removal and shorter procedure time, but did not reach concentrations obtained with standard epi-off

Corneal cross-linking: intrastromal riboflavin concentration in iontophoresis-assisted imbibition versus traditional and transepithelial techniques.

PURPOSE: To determine differences in riboflavin concentration in the anterior, intermediate, and posterior stroma after 3 corneal cross-linking imbibition techniques (standard epithelial [epi]-off, epi-on, and iontophoresis-assisted administration) of 0.1% riboflavin. DESIGN: Experimental laboratory investigation of human cadaver corneas not suitable for transplantation. METHODS: Ten corneas underwent imbibition with epi-on (n = 3), epi-off (n = 3), iontophoresis (n = 3), and saline exposure (control; n = 1). Femtosecond laser was used to produce 3 8-mm discs of the superficial (0-150 \u3bcm), intermediate (150-300 \u3bcm), and deep stroma (>300 \u3bcm). Riboflavin concentration was measured with high-performance liquid chromatography. The main outcome measure was riboflavin concentration at the 3 evaluated depths. RESULTS: The overall stromal concentration of riboflavin was 34.1 \ub1 7.1 \u3bcg/g in epi-off, 7.2 \ub1 3.7 \u3bcg/g in epi-on, and 15.0 \ub1 5.1 \u3bcg/g in iontophoresis. The mean riboflavin content in the superficial slice in the epi-off group was about 2-fold greater than that of the iontophoresis group (50.5 \ub1 5.3 \u3bcg/g and 23.6 \ub1 2.5 \u3bcg/g, respectively) and 4-fold greater than that of the epi-on group (11.7 \ub1 3.3 \u3bcg/g). Similar differences among the 3 groups were observed for the intermediate and posterior stromal slices, presenting an evident reduction of riboflavin concentration with increasing depth in all groups. Slice depth-dependent decrease in riboflavin concentration was statistically significant (general linear model (GLM); F1,6 = 62.265, P < .001), as was the group-dependent variation (GLM; F2,6 = 20.268, P = .002) and the slice depth group interaction (GLM; F2,6 = 18.004, P = .002). CONCLUSIONS: Corneal cross-linking transepithelial iontophoresis imbibition yielded greater and deeper riboflavin saturation with respect to conventional epi-on, while maintaining the advantages of avoiding epithelial removal and shorter procedure time, but did not reach concentrations obtained with standard epi-off

Opaque bubble layer incidence in Femtosecond laser-assisted LASIK: comparison among different flap design parameters

The purpose of this study was to evaluate the incidence of opaque bubble layer (OBL) in femtosecond laser-assisted in situ keratomileusis (LASIK) flaps created with the support of Visumax Carl Zeiss femtosecond laser, planned with different flap diameters (7.90, 8.0, and 8.20 mm) and the same laser energy and power settings. Incidence of intraoperative OBL in flaps of consecutive 108 patients (216 eyes) subjected to bilateral femtosecond-assisted LASIK was considered. Flap creation was performed with the same laser design parameters (spot distance and energy offset) and different presetting diameters of 7.90 mm (72 eyes, group 1), 8 mm (72 eyes, group 2), and 8.20 mm (72 eyes, group 3). The incidence of OBL was considered and its extension was reported measuring involvement of different four corneal flap quadrants in which was theoretically divided the entire flap area; based on these data, OBL presence was classified as none (no evidence of OBL), minimal (minimal presence in not more that one quadrants corneal flap), mild (OBL presence in almost two or three quadrants without tendency to invade central cornea), and moderate (OBL presence in almost three quadrants with tendency to invade central cornea). In group 1, the incidence of OBL was of 23.6 % (17 eyes) with a mild/moderate presence; in group 2, incidence was 20.8 % (15 eyes) with mild presence. Group 3 presented a reduced OBL incidence (4.1 %, 3 eye) with a minimal presence. No statistically significant difference was found between group 1 and 2 (p = 0.8414).We found statistically significant differences between group 1 and group 3 (p = 0.0012) and between groups 2 and 3 (p = 0.0044). A significant reduction and extension of OBL incidence were evident when LASIK flap settings diameter was increased, and flap edge was closer to the contact glass border; this is probably consequent to a more effective gas dispersion outside of corneal flap

In Vivo Confocal Microscopy of Stromal Lenticule Addition Keratoplasty for Advanced Keratoconus

PURPOSE: To investigate the in vivo corneal microscopic changes after femtosecond laser-assisted stromal lenticule addition keratoplasty in keratoconus by means of in vivo confocal microscopy. METHODS: Patients affected by advanced keratoconus were included in the study. Negative meniscus-shaped stromal lenticules, produced with a femtosecond laser (VisuMax; Carl Zeiss Meditec) from eye bank corneas were transplanted into a stromal pocket dissected in the recipient cornea at a depth of 120 μm. In vivo confocal microscopy was performed during the 12-month follow-up to investigate changes of the corneal and lenticule structure. RESULTS: Ten patients were enrolled in the study. No changes of the dendritic cell population were documented during the follow-up period. Mild edema and stromal keratocyte activation gradually decreased during the first month. Subbasal nerve density returned to preoperative values after 6 months. Donor-recipient interfaces appeared hyperreflective but gradually improved over time with significantly reduced reflectivity after 3 months. No evidence of stromal inflammatory cell migration or matrix opacification was observed. Endothelial and keratocyte density remained stable over time. A variable degree of stromal radially distributed folds, not visible on biomicroscopy, was observed in the lenticule and in the posterior recipient stroma. CONCLUSIONS: Stromal lenticule addition keratoplasty produces transitory nerve plexus density reduction and minor inflammatory reaction that rapidly decreases during the first month. Donor-recipient interface reflectivity is comparable to a femtosecond laser refractive procedure with no sign of stromal opacification or stromal rejection in 1 year of follow-up

Impact of Covid-19 on surgical activities and personnel: lessons for the future

Covid-19 pandemic has impacted professional, economic and social activities. In the surgical field, it has brought changes to operating activities, the organization of workforces, the protection measures for patients and personnel against possible intraoperative transmissions as well as training young surgeons. This study intends to assess the extent of this impact in our institution