Confocal and Histological Features After Poly(Ethylene Glycol) Diacrylate Corneal Inlay Implantation

Purpose: To evaluate the in vivo biocompatibility of photopolymerized poly(ethylene glycol) diacrylate (PEGDA) intrastromal inlays in rabbit corneas. Methods: Sixty-three eyes of 42 New Zealand rabbits were included. Manual intrastromal pockets were dissected in 42 eyes. PEGDA inlays were obtained using a specifically designed photomask and were inserted in the intrastromal pocket of 21 eyes (inlay group); the remaining 21 right eyes did not receive any implant (pocket-only group). Twenty-one eyes with no intervention were used as controls. In vivo confocal microscopy (IVCM) was performed at every visit. After 2 months, rabbits were sacrificed and corneas removed for histological analysis. Results: Corneas remained clear in all but two animals, and five cases of corneal neovascularization were seen (P = 0.2). Inlays remained stable without evidence of lateral or anterior migration, and no other complications were observed. No changes in anterior and posterior keratocyte density (P = 0.3 and P = 0.1, respectively) or endothelial cell density (P = 0.23) were observed between groups during the study time by IVCM. On pathology samples, thinning of the epithelium over the inlay area and epithelial hyperplasia over the edges were observed. A polygonal empty space with no evidence of PEGDA hydrogel within the midstroma was seen in the inlay group. Keratocytes were normal in shape and number in the vicinity of the PEGDA implant area. Conclusions: Photopolymerized PEGDA intrastromal inlays have shown relatively good safety and stability in rabbit corneas. Inlays were biostable in the corneal environment and remained transparent during follow up. Translational Relevance: The investigated PEGDA is promising for the development of biocompatible intrastromal implants.Supported in part by the Spanish Ministry of Science and Education through Apply Research, grant MAT2006-13708-CO2-01. The authors alone are responsible for the content and writing of the paper. Disclosure: A. Bidaguren, None; J. Mendicute, None; I. Madarieta, Tecnalia (E); N. Garagorri, Tecnalia (E

Stereoacuity Improvement using Random-Dot Video Games

Conventional amblyopia therapy involves occlusion or penalization of the dominant eye, though these methods enhance stereoscopic visual acuity in fewer than 30% of cases. To improve these results, we propose a treatment in the form of a video game, using random-dot stimuli and perceptual learning techniques to stimulate stereoacuity. The protocol is defined for stereo-deficient patients between 7-14 years of age who have already received treatment for amblyopia and have a monocular best corrected distance visual acuity of at least 0.1 logMAR. Patients are required to complete a perceptual learning program at home using the video game. While compliance is stored automatically in the cloud, periodic optometry center visits are used to track patient evolution and adjust the game's stereoscopic demand until the smallest detectable disparity is achieved. The protocol has proved to be successful, and effectiveness is gauged in terms of a two-level gain on a random stereoacuity test (global stereoacuity or cyclopean stereoacuity reference test). Moreover, the random-dot stimuli learning transfers to medial lateral stereoscopic acuity according to a Wirt Circles test, in which success criteria is a final stereoacuity of over 140", and the attained enhancement corresponds to no less than two levels of stereoscopic acuity. Six months later, a random-dot stereoacuity test recorded no reduction in the stereoacuity that was achieved

Corneal densitometry after photorefractive keratectomy, laser- assisted in situ keratomileusis, and small-incision lenticule extraction

Purpose: The aim of this study was to gain greater insight into the corneal densitometry changes occurring as a result of refractive surgery and to compare these changes across three widely used surgical techniques, namely, photorefractive keratectomy (PRK), laser-assisted in situ keratomileusis with a femtosecond laser (LASIK-FS), or ReLEx small-incision lenticule extraction (ReLEx SMILE). Patients and methods: Three hundred and thirty-six patients (184 male and 152 female patients) participated in this study. They were split into three groups according to the refractive surgery technique they had undergone: LASIK-FS (74 patients), PRK (153 patients), and ReLEx SMILE (109 patients). All participants underwent an exhaustive eye examination both before and after surgery. Pre- and postoperative corneal densitometry was measured using an Oculus Pentacam system. Results: The mean postoperative total corneal densitometry values were 16.53 ± 1.94 for the LASIK- FS group, 15.53 ± 1.65 for PRK, and 16.10 ± 1.54 for ReLEx SMILE. When corneal densitometry was analyzed for specific corneal areas, the values corresponding to the 0–2, 2–6, and 6–10 mm annuli were similar across the three surgical techniques. The only region in which differences were found was the peripheral area (Po0.05), but these variations across techniques were not statistically significant. Conclusions: Corneal densitometry can be used as an objective metric to assess corneal response to refractive surgery, and to monitor patients over time. Corneal densitometry was not negatively affected by any of the refractive surgical procedures under evaluation

A Lamellar Zn-Based Coordination Polymer Showing Increasing Photoluminescence upon Dehydration

The present study reports on a 2D lamellar coordination polymer (CP) of {[Zn(µ3-pmdc)(H2O)]·H2O}n formula (pmdc = pyrimidine-4,6-dicarboxylate). This CP is synthesized under an appropriate acid-base reaction between the gently mortared reagents in the solid state through a solvent-free procedure that avoids the presence of concomitant byproducts. The X-ray crystal structure reveals the occurrence of Zn2 entities connected through carboxylate groups of pmdc, which behave as triconnected nodes, giving rise to six-membered ring-based layers that are piled up through hydrogen bonding interactions. In addition to a routine physico-chemical characterization, the thermal evolution of the compound has been studied by combining thermogravimetric and thermodiffractometric data. The photoluminescence properties are characterized in the solid state and the processes governing the spectra are described using time-dependent density-functional theory (TD-DFT) with two different approaches employing different program packages. The emissive capacity of the material is further analyzed according to the dehydration and decreasing temperature of the polycrystalline sampleThis research was funded by Gobierno Vasco/Eusko Jaurlaritza (IT1755-22, IT1722-22 and IT1500-22) and Junta de Andalucía (B-FQM-734-UGR20, ProyExcel_00386 and FQM-394)

Multicenter Evaluation of Time, Operational, and Economic Efficiencies of a New Preloaded Intraocular Lens Delivery System versus Manual Intraocular Lens Delivery

Purpose: To evaluate intraoperative intraocular lens (IOL) delivery time and total surgical case time using the UltraSert preloaded delivery system (System U) during routine cataract surgeries and to compare with the manually loaded Monarch delivery system (System M). Physician satisfaction with System U was also assessed. Patients and Methods: In this prospective observational study, subjects ≥ 18 years old underwent cataract surgery in 1 eye and received the AcrySof IQ IOL via the manually loaded System M (n=103) or the AcrySof IQ IOL model AU00T0 via the preloaded System U (n=93). Procedures were digitally recorded by an external camera or by a camera within the operating microscope. Device preparation, IOL delivery, and IOL positioning times were evaluated by 2 independent graders. Pearson χ2 test or Fisher exact test was used for categorical variables and Student’s t-test or Wilcoxon rank-sum test for continuous variables (all tests were 2-sided and performed at a 5% α-level). Physician satisfaction levels were assessed using questionnaires. Results: Lens delivery time was similar for System U and System M (12.9± 5.1 and 12.2± 6.3 s; P=0.412). Mean device preparation time for System U was significantly shorter compared with System M (30.3± 6.6 versus 59.8± 31.0 s; P< 0.05). This resulted in a significantly shorter total intraoperative time (device preparation + lens delivery) with System U versus System M (43.0± 8.6 versus 72.0± 32.5 s; P< 0.05). Total surgical case time (device preparation + lens delivery + lens positioning and unfolding) was shorter for System U versus System M (56.6± 12.6 versus 89.6± 34.6 s; P< 0.05). Physicians reported greater satisfaction levels with System U compared with other devices. Conclusion: Use of the preloaded delivery system (System U) resulted in faster device preparation and reduced total surgical time compared with the manually loaded system (System M). System U was intuitive to use, and physicians preferred it to other devices

Recommendations for ophthalmologic practice during the easing of COVID-19 control measures

In the context of the COVID-19 pandemic, this paper provides recommendations for medical eye care during the easing of control measures after lockdown. The guidelines presented are based on a literature review and consensus among all Spanish Ophthalmology Societies regarding protection measures recommended for the ophthalmologic care of patients with or without confirmed COVID-19 in outpatient, inpatient, emergency and surgery settings. We recommend that all measures be adapted to the circumstances and availability of personal protective equipment at each centre and also highlight the need to periodically update recommendations as we may need to readopt more restrictive measures depending on the local epidemiology of the virus. These guidelines are designed to avoid the transmission of SARS-CoV-2 among both patients and healthcare staff as we gradually return to normal medical practice, to prevent postoperative complications and try to reduce possible deficiencies in the diagnosis, treatment and follow-up of the ophthalmic diseases. With this update (5th) the Spanish Society of Ophthalmology is placed as one of the major ophthalmology societies providing periodic and systematized recommendations for ophthalmic care during the COVID-19 pandemic

Anterior and posterior capsule densitometry levels after femtosecond laser-assisted cataract surgery

AIM: To analyze and compare five different variables over one year follow-up (1wk, 1, 3, 6 and 12mo): anterior capsule (AC), and posterior capsule (PC) area densitometry values, AC and PC linear densitometry values, and AC opening area reduction ratio after femtosecond laser-assisted cataract surgery. METHODS: This was a prospective comparative study. Seventy-one patients underwent femtosecond laser-assisted cataract surgery on single eye between June 2014 and December 2015. A 5.0 mm diameter laser assisted anterior capsulotomy was performed on all eyes. In every post-surgery evaluation, AC opacificaction (ACO) and PC opacification (PCO) density levels were provided by Oculus Pentacam®HR using area and linear densitometry methods. Digital images were captured with a slit-lamp Topcon photographic camera and IMAGEnet® 5 software. The AC opening area on the digital images was measured using the Sketchandcalc area calculator and converted to reduction ratio levels. RESULTS: Using Pearson correlation coefficient (PCC), we found no correlation (r=-0.091, P=0.46) in the twelfth month assessment between the evolution of ACO area densitometry values and PCO area densitometry values considered as independent variables. We found no correlation, using PCC (r=-0.096, P=0.43) between the evolution of ACO linear densitometry values and PCO linear densitometry values, in the twelfth month visit, working both as independent variables. AC linear densitometry levels and AC area densitometry levels continued to grow strongly from sixth to twelfth months. Analysis of the values of AC opening area reduction ratio (1wk, 1, 3, 6, 12mo) revealed statistically significant differences between the values of successive examinations but the magnitude of the change decreased. In the final period of monitoring between six and twelve months the magnitude of change was low. CONCLUSION: Our results show strong increases of Scheimpflug ACO densitometry values from the sixth to the twelfth month while capsulorhexis area reduction ratio levels displayed a considerable decrease. We found no correlation between ACO area and linear densitometry values and PCO area and linear densitometry values, in the twelfth month examination, working as independent variables

A Random Dot Computer Video Game Improves Stereopsis

SIGNIFICANCE Currently, treatments for amblyopia are occlusion or penalization of the stronger fellow eye. Fewer than 30% of patients improve stereoacuity using these treatments. In order to improve these outcomes, this group proposes a treatment to stimulate the stereoacuity through perceptual learning in a game format for use at home. PURPOSE The aim of this study was to determine whether perceptual learning with random dot stimuli (RDS) in the form of a computer video game improves stereopsis in patients with a history of amblyopia. METHODS Thirty-two stereo-deficient patients (7 to 14 years old) previously treated for amblyopia participated in a prospective, randomized, double-blind study. Participants followed a perceptual learning program at home using RDS software. In the experimental group, the demand of stereopsis was increased, until reaching the lowest detectable disparity. In the comparison group, the stimulation interval was a constant (840 to 750”). Stereoacuity was evaluated with the Randot Preschool Stereoacuity Test (RPST) and the Wirt Circles. RESULTS Median compliance was 100% (interquartile range [IQR] = 78.50 to 100). Log10 stereoacuity outcomes were significantly different between groups (RPST, P = .041; Wirt Circles Test, P = .009). Median stereoacuity improvement with RPST was 50% (IQR = 0.00 to 75%) and 0% (IQR = 0.00 to 7.5%), respectively, for experimental and comparison groups (P = .008). Wirt Circles improvement was 46.42% (IQR = 6.25 to 73.75%) and 0% (IQR = 0.00 to 57.50%), respectively, for experimental and comparison groups (P = .089). Stereoacuity improvement was not different between groups when success was considered a 70% gain in RPST (P = .113); it was statistically different when success was considered a gain of two levels on Wirt Circles and stereoacuity 140” or less (P = .023). Stereoacuity remained stable after 6 months when measured with RPST, whereas it worsened in two subjects when measured with Wirt Circles. CONCLUSIONS Direct stimulation of stereopsis at home using RDS in a game environment improves the stereoacuity in stereo-deficient subjects with a history of amblyopia.Sin financiación1.577 JCR (2018) Q3, 40/60 Ophthalmology0.851 SJR (2018) Q1, 2/12 Optometry; Q2, 35/126 OphthalmologyNo data IDR 2018UE