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Purpose: The purpose of this study was to explore the optimal shape of customized lenticules for stromal lenticule addition keratoplasty (SLAK) for off-centered ectasia., Methods: Two different methods to create ex vivo models of eccentric-keratoconus were investigated. Twelve human corneas were used to create model 1 by a hyperopic photorefractive keratectomy (PRK), and model 2 by masked phototherapeutic keratectomy (PTK) on the anterior corneal surface, whereas both types received myopic ablation of the posterior surface. Keratoconus models underwent a modified femtosecond laser (FSL) flap-cut to create stromal pockets. Sixteen human corneas underwent FSL dissection to obtain four lenticule types: type I (planar) and type II (negative) lenticules were used without modifications, whereas type III (customized-planar), and type IV (customized-negative) lenticules underwent further masked-PRK to obtain an asymmetric bow-tie shape. Topographic, aberrometric analysis, and anterior segment optical coherence tomography (AS-OCT) were performed in all recipient corneas before and after lenticule implantation., Results: Keratoconus model was successfully reproduced. Tomographic analysis showed a significant inferiorly decentered corneal steepening with coherent stromal thinning. Model 2 reproduced better the curvature of real keratoconus. Lenticules type I implantation induced a homogeneous corneal thickening, type III produced higher thickening in the inferior half of the cornea. Type II determined a maximal peripheral pachymetric increase, with a gradual reduction toward the center, and type IV presented an asymmetric peripheral thickening. Topographic assessment showed a cone apex flattening in all cases, but it was significantly higher in types II and IV. Customized lenticules improved significantly corneal surface regularity regarding types I and II., Conclusions: The approach of customizing lenticules by increasing their asymmetry and tailoring the re-shaping effects, may improve SLAK outcomes in eccentric keratoconus.

Introduction: The aim of this study was to assess early anatomical and functional changes after brolucizumab intravitreal injection (BIVI) in patients with age-related macular degeneration (AMD) and macular neovascularization type 1 (MNV1)., Methods: A total of 24 eyes of 24 patients suffering from naïve AMD with MNV1 candidates to BIVI as per label with q12/q8 dosing regimen after the loading dose were enrolled in this prospective study. Main outcome measures during a 16-week follow-up period included changes in best corrected visual acuity (BCVA), central macular thickness (CMT), subfoveal subretinal fluid (SSRF) thickness (SSRFT), subfoveal sub-retinal pigment epithelium (RPE) fluid thickness (SSRPEFT), subfoveal choroidal thickness (SFCT), and pigment epithelial detachment (PED) maximum height (PED-MH). In addition, MNV1 flow area; percentages of eyes with intraretinal fluid (IRF), subretinal fluid, and sub-RPE fluid at different time points; and percentages of eyes candidates to a q8 or q12 injection interval after disease activity assessment at week 16 were evaluated., Results: BCVA improved significantly from baseline (T0) to week 12 (T3) (p = 0.028). CMT showed a significant reduction from 456 ± 123 µm at T0 to 265 ± 85 µm at T3 (p < 0.001). SSRFT and SSRPEFT reduced significantly as well (p < 0.001 and p = 0.049, respectively). PED-MH and SFCT reduced significantly at the different time points (p = 0.020; p = 0.006, respectively). IRF presence changed significantly from 41.7% of eyes at T0 to 20.8% at T3 (p = 0.045). SSRF reduced significantly during follow-up, being present in 62.5% of eyes at T0 and 4.2% of eyes at T3 (p < 0.001). Subfoveal sub-RPE fluid decreased significantly during time, being present in 20.8% of eyes at T0 and 0% at T3 (p = 0.013). Most of the eyes (18 eyes, 75%) at week 16 after disease activity assessment were shifted in the q12 interval, and only a minority of eyes shifted in a q8 interval (6 eyes, 25%)., Conclusion: Brolucizumab is efficient in AMD patients with MNV1 by reducing all retinal fluids during the loading phase and shows reduction of macular thickness, choroidal thickness, and PED height. Most eyes at disease activity assessment (75%) fall into 12-week interval and the minority (25%) into the 8-week interval., (© 2022 The Author(s). Published by S. Karger AG, Basel.)

Purpose: To compare macular pigment optical density (MPOD) in healthy eyes versus eyes affected by primary epiretinal membrane (ERM) in different stages and to assess the relation between MPOD and optical coherence tomography findings., Methods: Prospective cross-sectional study of 62 eyes of 62 patients affected by unilateral primary ERM. Contralateral healthy eyes from the same patients were used as a control group. Main outcome measures were MPOD, ERM stage, central foveal thickness (CFT), outer nuclear layer thickness (ONLT), integrity of outer retinal bands, and presence of central bouquet abnormalities., Results: In the study group, mean CFT was 444 ± 75 μm and mean ONLT was 245 ± 40 μm, whereas in the control group, mean CFT was 230 ± 21 μm and mean ONLT was 102 ± 14 μm (P < 0.001). Mean MPOD was 0.86 ± 0.07 in eyes with ERM and 0.48 ± 0.09 in contralateral healthy eyes (P < 0.001). Macular pigment optical density was associated with CFT (P = 0.006) and ONLT (P < 0.001), whereas no significant associations were observed between MPOD and outer retinal bands integrity (P = 0.14) and central bouquet abnormalities (P = 0.08)., Conclusion: Macular pigment optical density increased in eyes affected by primary ERM proportionally to CFT and, especially, ONLT. Probably, centripetal forces exerted by ERM contraction on the retinal surface lead to a progressive foveal packing of foveal Müller cells.

To compare the anatomical/functional changes after navigated subthreshold pulse laser (SML) and oral eplerenone therapy for chronic central serous chorioretinopathy (cCSC). A total of 36 eyes of 36 patients suffering from cCSC treated with navigated SML (Navilas® 577s; OD-OS GmbH, near Berlin, Germany) (18 eyes, SML group) and oral eplerenone (18 eyes, eplerenone group) were enrolled in this retrospective study. Main outcome measures during a 3-month follow up period included changes of best corrected visual acuity (BCVA), central macular thickness (CMT), foveal subretinal fluid thickness (FSRFT), and subfoveal choroidal thickness (SFCT). At baseline average duration of symptoms was 6.8 ± 0.6 months in SML group and 6.4 ± 0.9 months in eplerenone group (p = 0.127). Mean BCVA, CMT and FSRFT changed significantly over time (p < 0.001). From baseline to 90 days the BCVA improved from 0.3 ± 0.1 to 0.1 ± 0.1 logMAR in SML group and from 0.3 ± 0. to 0.2 ± 0.1 logMAR in eplerenone group, CMT reduced from 357.1 ± 104.3 to 210.6 ± 46.7 μm and from 428.7 ± 107.7 to 332.5 ± 27.5 μm in SML group and eplerenone group respectively, FSRFT reduced from 144.4 ± 108.2 to 22.6 ± 37.2 μm and from 217.1 ± 105.9 to 54.4 ± 86.2 μm in SML group and eplerenone group. 55.6% of patients in SML group and 66.7% in eplerenone group showed a complete resolution of FSRFT during follow up. The interaction between group and time was statistically significant with greater absolute variation for CMT and FSRFT in SML group compared to eplerenone group (p < 0.001 and p = 0.043). SFCT did not change significantly during follow up (p = 0.083) for both groups. Both navigated SML and oral eplerenone were effective treatments showing recovery of retinal morphology and related visual acuity improvement in cCSC., (© 2022. The Author(s).)

Background and Objectives : Vision impairments and related blindness are major public health problems. The prevalence of eye disease and barriers to optimal care markedly vary among different geographic areas. In the Abruzzo region (central Italy), an epidemiological surveillance on the state of ocular health in the population aged over 50 years was performed in 2019. Materials and Methods : Participants were sampled to be representative of the region's inhabitants. Data were collected through a telephone interview and an eye examination. Prevalence of cataract, glaucoma, retinopathy, and maculopathy was assessed. The Cohen's kappa (k) was used to measure the agreement between the presence of eye disease and awareness of the disease by the participants. Results : Overall, 983 people with a mean age of 66.0 ± 9.5 years were included in the study. The prevalence of cataracts, glaucoma, maculopathy, and retinopathy was 52.6%, 5.3%, 5.6%, and 29.1%, respectively. Among the total of the affected people, those aware of their condition were 21.8% (k = 0.12, slight agreement) for cataract, 65.4% (k = 0.78, substantial agreement) for glaucoma, 7.1% (k = 0.10, slight agreement) for maculopathy, and 0% for retinopathy (k = -0.004, agreement lower than that expected by chance). Refractive defects were corrected in the vast majority of participants. Conclusion : In the Abruzzo region, about two thirds of citizens aged 50 years or over suffer from cataract, glaucoma, retinopathy, or maculopathy, which are recognized as leading causes of blindness. Many people with eye disease do not know they have it. These data can be used by clinicians and policymakers to undertake clinical, political, and social actions.

(1) Background: The aim of this observational comparative study was to investigate early retinal vascular and functional changes in patients undergoing vitreoretinal surgery for idiopathic epiretinal membrane (iERM) or macular hole (MH) using a widefield swept-source optical coherence tomography angiography (WSS-OCTA). (2) Methods: Forty one diseased eyes were enrolled in the study. Twenty three eyes with iERM diagnosis (ERM group) underwent 25-gauge vitrectomy with inner limiting membrane (ILM) and MER peeling, while eighteen eyes with MH (MH group) underwent 25-gauge vitrectomy with inverted flap technique. Functional and anatomical/perfusion parameters were evaluated pre- and postoperatively in all eyes by means of WSS-OCTA system, microperimetry (MP3), best corrected visual acuity assessment, central macular thickness (CMT) and MH diameter calculation. For each eye, 12 × 12 mm OCTA volume scans were acquired by a retinal specialist and a semi-automated algorithm was used for a quantitative vessel analysis of the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris (CC). In detail, perfusion density (PD) of the SCP, DCP and CC was evaluated in four circles (one central in the macular area of 5 mm diameter; three midperiphery circles (temporal, superior and inferior) of 3 mm). In addition, the vessel length density (VLD) of the SCP and DCP for the same circles was quantified. (3) Results: In the MH group, PD of the SCP significantly increased in the macular area ( p = 0.018) and in the superior ring ( p = 0.016); PD of the DCP significantly increased in the macular area ( p = 0.015) and in the superior and inferior ring ( p = 0.016) 3 months after surgery. In the ERM group, PD of the SCP and DCP significantly increased in the macular area and superior ring, respectively ( p = 0.001; p = 0.032), 3 months after surgery. During follow-up there was a significant improvement in terms of functional (Best corrected visual acuity, p = 0.007 and p = 0.029; microperimetry ((MP3) 10°, p = 0.003 and p = 0.004; MP3 2°, p = 0.028 and p = 0.003 in MH group and ERM group respectively) and anatomical parameters (CMT, p = 0.049 in ERM group; hole complete closure in MH group). (4) Conclusions: After vitreoretinal surgery, early retinal vascular and functional changes can be promptly observed and quantified to monitor and potentially predict surgery outcomes. Widefield OCTA devices allow for a detailed microvasculature analysis of retina and choriocapillaris in the macular area and in the periphery, showing a different behaviour of retinal sectors in two distinct vitreoretinal disorders.

Objectives: The inverted internal limiting membrane (ILM) flap technique has been shown to increase the success rate in large full-thickness macular holes (FTMHs) and in FTMHs associated with high myopia. The aim of our study was to confirm the efficacy and safety of inverted ILM flap technique in idiopathic FTMHs independent of their dimensions and to assess functional outcomes and their correlation to morphologic findings., Methods: Sixteen consecutive patients affected by idiopathic FTMH were enrolled in this prospective study. The preoperative mean (±SD) diameter of the FTMH was 422 (±106) µ m. All patients underwent vitrectomy and ILM peeling with inverted ILM flap. At 1-, 3-, and 6-month postoperative visits, visual acuity measurement, indirect ophthalmoscopy, and microperimetry were performed, and the foveal contour and the integrity of the ellipsoid zone (EZ) and external limiting membrane (ELM) were investigated using spectral domain optical coherence tomography (SD-OCT)., Results: At six months postoperatively, 15 out of 16 (93.75%) patients obtained FTMH closure. The mean best corrected visual acuity (BCVA) improved from 1.1 LogMAR to 0.3 LogMAR, and the mean retinal sensitivity (MS) improved from 7.2 to 23.4 dB. ELM defects were evident in 1 out of 16 (6.25%) eyes, and EZ defects were detected in 2 out of 16 (12,50%) eyes. A statistically significant relationship was observed between BCVA, MS, and EZ reconstitution at each follow-up visit., Conclusions: Results confirm that the inverted ILM flap technique is a safe and effective option for FTMH treatment and show a strong correlation between higher BCVAs and MSs and EZ reconstitution after surgery., Competing Interests: The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2021 Paolo Carpineto et al.)

Purpose: To describe the reliability and the limits of bursa premacularis (BPM) evaluation using a swept source optical coherence tomography (SS-OCT) device with enface and 16 mm-high definition (HD) longitudinal scans., Methods: 60 eyes of 60 subjects were enrolled and imaged with SS-OCT system (PLEX Elite 9000, Carl Zeiss Meditec Inc., Dublin, CA, USA). BPM area was measured using enface scans imported to ImageJ. HD horizontal and vertical longitudinal scans centered at the fovea were used to detect width (W) and central thickness (CT) of BPM at baseline (T 0 ) and after 30 minutes (T 30 ) performed by two different observers. An enhanced vitreous visualization software provided by the manufacturer of the device was used to highlight vitreous structures., Results: BPM was identifiable in 100% of eyes using both horizontal and vertical longitudinal scans. On horizontal scan, BPM was not entirely measurable in 21.7% and in 18.3% of cases at T 0 and T 30 , respectively. On vertical scan, BPM was not entirely measurable in 75.0% and in 81.7% at T 0 and T 30 , respectively. No statistically significant differences were found between the two different time measurements with an intraclass correlation coefficient above 70%. Median BPM area was 26.9 (Q 1 -Q 3 : 19.5-40.5) mm 2 . In en face imaging, the most frequent BPM shape was the boat one., Conclusion: SS-OCT is a reliable tool for a detailed quantification and mapping of BPM, and it is able to add useful details about the morphological BPM features in youth population. However, the enhanced visualization of the vitreous structures is still a challenge, also with the most forefront devices., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Paolo Carpineto et al.)

We investigate a kinetic heat engine model composed of particles enclosed in a box where one side acts as a thermostat and the opposite side is a piston exerting a given pressure. Pressure and temperature are varied in a cyclical protocol of period τ: their relative excursions, δ and ε, respectively, constitute the thermodynamic forces dragging the system out of equilibrium. The analysis of the entropy production of the system allows us to define the conjugated fluxes, which are proportional to the extracted work and the consumed heat. In the limit of small δ and ε the fluxes are linear in the forces through a τ-dependent Onsager matrix whose off-diagonal elements satisfy a reciprocal relation. The dynamics of the piston can be approximated, through a coarse-graining procedure, by a Klein-Kramers equation which-in the linear regime-yields analytic expressions for the Onsager coefficients and the entropy production. A study of the efficiency at maximum power shows that the Curzon-Ahlborn formula is always an upper limit which is approached at increasing values of the thermodynamic forces, i.e., outside of the linear regime. In all our analysis the adiabatic limit τ→∞ and the the small-force limit δ,ε→0 are not directly related.

We study a molecular engine constituted by a gas of N∼102 molecules enclosed between a massive piston and a thermostat. The force acting on the piston and the temperature of the thermostat are cyclically changed with a finite period τ. In the adiabatic limit τ→∞, even for finite size N, the average work and heat reproduce the thermodynamic values, recovering the Carnot result for the efficiency. The system exhibits a stall time τ* where the net work is zero: for τ<τ* it consumes work instead of producing it, acting as a refrigerator or as a heat sink. At τ>τ* the efficiency at maximum power is close to the Curzorn-Ahlborn limit. The fluctuations of work and heat display approximatively a Gaussian behavior. Based upon kinetic theory, we develop a three-variables Langevin model in which the piston's position and velocity are linearly coupled together with the internal energy of the gas. The model reproduces many of the system's features, such as the inversion of the work's sign, the efficiency at maximum power, and the approximate shape of the fluctuations. A further simplification in the model allows us to compute analytically the average work, explaining its nontrivial dependence on τ.