P01-A120†Pre-dissected dmek stored in an active storage machine: feasibility study.

PURPOSE: The number of endothelial grafts precut by eye banks increases. Their shelf life is limited to a few days. We previously demonstrated the superiority of an active storage machine (ASM) over organ culture (passive) for whole corneas. AIMS: To measure the endothelial viability of pre-dissected DMEK after 3 and 10 days of storage in our ASM in a preclinical study. METHODS: Pairs of human corneas were included. The endothelial cell density (ECD in cells/mm2), thickness and transparency of corneas were measured before graft preparation. Descemet's membrane (DM) was peeled using the no-touch technique leaving the graft attached to the center of the cornea (on approx. 1mm2). After randomization, one cornea was kept in organ culture (OC) and the other in the ASM (21 mmHg, 2.6 µL/min) in the same medium (CorneaMax, Eurobio). The final viable ECD was determined using the triple staining with Hoechst-Ethidium-Calcein-AM. In addition, the expression of CD166 and NCAM (lateral membranes), ZO-1 (apical junctions), Na+/K+ ATPase (endothelial pump function) and COX-IV (mitochondrial content) was studied by immunostaining to characterize endothelial cells after the storage. RESULTS: Initial ECDs were comparable: 2185±232 cells/mm2 in the ASM versus 2276±328 in OC for the 3-day period and 2680±416 cells/mm2 in the ASM versus 2644±420 in OC for the 10-day period. The DMs did not fold back in either BR or OC. The viable ECD did not differ significantly between the ASM and OC for either storage period: 2378±501 (ASM) versus 2342±503 (OC) for the 3-day period (n=8 pairs and p=0.624) and 2482±288 (ASM) versus 2579±315 (OC) for the 10-day period (n=5 pairs and p=0.176). Corneas were more transparent and thinner in the ASM than in OC after 3 days (916±86 versus 1193±136µm, p=0.0001) and 10 days (957±128 versus 1220±105µm, p=0.0625). The functional and structural markers studied were expressed in both groups after 3 and 10 days, some better preserved in the ASM. CONCLUSION: The storage of precut DMEKs is possible in ASM and OC for at least 10 days. Interestingly, a pre-dissected endothelium continues to partially exert its pump function into the ASM. In practice, this could allow the stroma to be used for DALK without further deswelling. In addition to improving the storage of whole grafts, the ASM allows the storage of precut DMEKs for up to 10 days with excellent endothelial survival.

Femtosecond laser-cut autologous anterior lens capsule transplantation to treat refractory macular holes.

BACKGROUND: To report the long-term outcomes of round autologous anterior lens capsules (ALCs) cut by a femtosecond laser (FSL) and transplanted onto refractory macular holes (MHs) in a prospective interventional study. METHODS: Three eyes of three patients were included for persistent MH after reattached rhegmatogenous retinal detachment (RRD) (n = 2) or RRD recurrence by persistent MH (n = 1), in a university hospital. A 6 mm diameter ALC disc was carefully extracted during FSL-assisted lens extraction, stained with 0.06% trypan blue, decellularised, transplanted using a catheter and unfolded over the MH. Gas or silicone-oil tamponade was used. At 1 year, the main criterion was anatomic success, defined as complete MH closure. Secondary criteria were changes in best corrected visual acuity (BCVA), ellipsoid zone (EZ) and external limiting membrane (ELM) defects, complications. RESULTS: Baseline data were: minimum and maximum diameters, respectively 887, 1079 and 1180 µm; 1260, 1213 and 1350 µm; central posterior staphyloma in two highly myopic eyes; number of prior surgeries 2 ± 1. At 1 year, the three MHs were closed with stable transplanted ALCs. Distant BCVA improved respectively from 3.0, 0.8, 3.0 to 1.0, 0.2, 0.7 logMAR, i.e. all eyes achieved ≥0.3 logMAR improvement. All patients had decreased EZ and ELM defects, without reaching normal profile. No adverse event occurred. CONCLUSIONS: FSL-cut ALC helps standardise this challenging surgery: it prevents from tears and facilitates manipulation, so that the ALC disc is perfectly transparent and biocompatible, with a large MH overlap. One-year follow-up highlighted that this technique helps safely close refractory MHs with satisfactory visual recovery.

Characterization of Femtosecond Laser and Porcine Crystalline Lens Interactions by Optical Microscopy.

The use of ultrafast laser pulses for eye anterior segment surgery has seen a tremendous growth of interest as the technique has revolutionized the field, from the treatment of myopia, hyperopia, and presbyopia in the cornea to laser-assisted cataract surgery of the crystalline lens. For the latter, a comprehensive understanding of the laser-tissue interaction has yet to be achieved, mainly because of the challenge of observing the interaction zone in situ with sufficient spatial and temporal resolution in the complex and multi-layered tissue of the crystalline lens. We report here on the dedicated characterization results of the laser-tissue interaction zone in the ex vivo porcine lens using three different methods: in situ and real-time microscopy, wide-field optical imaging, and phase-contrast microscopy of the histological cross sections. These complementary approaches together revealed new physical and biological consequences of laser irradiation: a low-energy interaction regime (pulse energy below ~1 µJ) with very limited cavitation effects and a stronger photo-disruption regime (pulse energy above 1 µJ) with a long cavitation duration from seconds to minutes, resulting in elongated spots. These advances in the understanding of the ultrafast laser's interactions with the lens are of the utmost importance for the preparation of the next-generation treatments that will be applied to the lens.

Objective measurement of adherence to topical steroid medication after penetrating keratoplasty using an electronic monitoring aid: A pilot study.

Objectives: Corneal transplantation is the most common transplant worldwide and its success critically depends on the management of corneal graft rejection through topical steroid therapy during the first 12 months after surgery. There is currently no published data on adherence after keratoplasty. This pilot study aims to explore the adherence to topical steroid after penetrating keratoplasty using a smart electronic device. Methods: Thirty patients undergoing penetrating keratoplasty were included to evaluate the adherence to topical dexamethasone medication for 12 months after surgery. Patients received the usual post-transplantation treatment (topical dexamethasone) and follow-up after surgery (day 15, months 1, 2, 3, 4, 5, 6, 9, and 12). Adherence to treatment was monitored using the KaliJAR device (Kali Care, Santa Clara, CA, USA), which recorded the number of single-dose units (SDU) discarded. At control visits, data recorded by the device were compared to the manually count of SDU. Adherence ratio and individual adherence curve were explored for all patients. Results: Data from 27 patients showed a high agreement between adherence ratio calculated based on the device data and obtained from manual counting of the discarded SDU (intraclass coefficient correlation of 0.87 [95% CI: 0.738-0.938]). Mean adherence to the treatment over the 12-month study period was 95.2 ± 4%. Conclusions: Adherence to topical dexamethasone for 12 months after corneal transplantation was high. The connected device was able to record accurately the discarded SDU. This approach would be a particular interest in the early identification and personalized follow-up of poorly adherent patients.

New Devitalized Freeze-Dried Human Umbilical Cord Amniotic Membrane as an Innovative Treatment of Ocular Surface Defects: Preclinical Results.

A preclinical study was performed to investigate the efficacy and safety of a new viral inactivated, devitalized, freeze-dried and gamma-sterilized human umbilical cord amniotic membrane (lhUC-AM) for the treatment of deep scleral and corneal defects with or without perforation. Firstly, lhUC-AM was investigated on experimental deep sclerectomy in rabbit eyes (n = 12) and compared to autograft (n = 4) on cross section histology. Secondly, lhUC-AM was studied on a selected series of uncontrolled cases of corneal defects (n = 18) with or without perforation, in dogs and cats. lhUC-AM tolerance, reconstruction of the deep corneal lesion and recovery of the structural aspect of the tissue were followed post-surgery. In experimental deep sclerectomy, histology showed that the lhUC-AM was well tolerated and degraded completely in 45 days while allowing an overall quality and kinetic of scleral regeneration, similar to autograft. In the clinical situations, lhUC-AM was well tolerated, with ocular inflammatory signs quickly decreasing after surgery. Mean follow-up was 16.40 ± 11.43 months. In 15 out of 18 cases, lhUC-AM allowed ocular surface wound healing. The ocular surface was fully reconstructed three months after surgery. This study suggests a good safety and efficacy profile of lhUC-AM in the treatment of deep corneal or scleral defect in animals. This new tissue should now facilitate the treatment of severe ocular surface diseases in humans.

Treatment of Mechanical Corneal Wounds Emergencies during the COVID-19 Pandemic: Absorbable 10-0 Vicryl (Polyglactin 910) Sutures as a Suitable Strategy.

Background­The COVID-19 pandemic has changed our standard practices: operating rooms were only available for functional emergencies and outpatient visits were drastically reduced in favor of telemedicine. Aim: To report the personalized "one-shot" surgery using absorbable 10-0 Vicryl (V10-0) or polyglactin 910 monofilament in mechanical corneal injuries from February 2020 to December 2021. Methods­Prospective case series with at least 12-months' follow-up, in a French university hospital. Among the overall population of open or closed-globe emergencies (n = 40), non-penetrating corneal lamellar lacerations (long axis > 2 mm) in zone 1 (OTC group) were treated with V10-0 suture(s) (n = 10), replacing traditional non-absorbable 10-0 nylon suture(s) or medical options in first line. The outpatient visits were performed on day (D)10, month (M)2, M6 then every six months. One interim visit by phone teleconsultation was scheduled between D10 and M2, and other(s) as needed. The main outcome was best-corrected visual acuity (BCVA) at M6. Secondary outcomes included mainly corneal astigmatism (CA) at M6 complications. Results­Among the ten corneal wounds, there were three children (30%), eight domestic accidents (80%), three eyes with metallic foreign bodies (30%), four open-globe injuries (40%), and nine eyes that received high-speed projectiles or sharp objects (90%). The complete V10-0 suture(s) absorption occurred in all eyes between D10 and M2. At M6, mean far and near BCVA decreased from 0.680 ± 0.753 and 0.490 ± 0.338 preoperatively to 0.050 ± 0.071 and 0.220 ± 0.063 logMAR (p = 0.019 and p = 0.025 respectively), mean CA decreased from 4.82 ± 3.86 preoperatively to 1.15 ± 0.66 diopters (p = 0.008). BCVA and CA were unchanged thereafter. No serious adverse event nor repeated surgery occurred. The mean number of teleconsultations was 1.20 ± 0.63 without an additional nonscheduled outpatient visit. Conclusions­The absorbable V10-0 sutures might be a safe and effective alternative for eligible corneal wounds, while reducing the number of outpatient visits, especially for children (no suture removal). The COVID-19 pandemic highlighted that they are ideally suited to logistical challenges.

Tissue engineered endothelial keratoplasty in rabbit: tips and tricks.

PURPOSE: To report a detailed surgical procedure of tissue engineered endothelial keratoplasty (TEEK) in a rabbit model and its postoperative evaluation. METHODS: TEEKs were prepared 7 days before transplantation by seeding human or rabbit corneal endothelial cells on either femtosecond laser-cut ultrathin human stromal lamellae (fs-UTSL) or femtosecond laser-cut human anterior lens capsule (fs-HALC). Thirty transplantations were performed on aphakic eyes. Recombinant tissue plasminogen activator (rTPA) was used throughout the surgery. The native endothelium was removed by full-surface scraping and central descemetorhexis. The transplantation was performed as a human Descemet's membrane endothelial keratoplasty. Controls included Descemetorhexis only and transplantation of carrier alone. Postoperative follow-up was performed by slit lamp and optical coherence tomography, followed by histology. RESULTS: Controls remained oedematous. No fibrin occurred during surgery. All but three TEEKs adhered immediately. One/6 fs-UTSL and 9/16 fs-HALC cleared perfectly (p = 0.161). All failures could be explained by at least one of the following causes intraoperative bleeding, vitreous prolapsus, early partial detachment, postoperative irido corneal synechiea/angle closure. Presumed immune rejection was observed in three rabbits only after 4 weeks. Immunostaining with anti-human CD166 allowed to perfectly differentiate human cells from rabbit cells. In successful TEEK at 3 or 4 weeks, human cells formed a normal endothelium and started migrating outside the carrier. CONCLUSION: Though the transplantation of a TEEK in rabbits is a complex model with many causes of failure, established procedure including use of rTPA allows reliable preclinical study. In addition, we suggest that fs-HALC might be a potential carrier for TEEK.

Epiretinal large disc of blue-stained lyophilized amniotic membrane to treat complex macular holes: a 1-year follow-up.

PURPOSE: To report the long-term outcomes of large diameter epiretinal lyophilized amniotic membranes (lAMs) in recurrent or persistent macular holes (MHs) with or without rhegmatogenous retinal detachment (RRD), in a prospective interventional case series. METHODS: Ten eyes of 10 patients underwent pars plana vitrectomy for MH-associated RRD (n = 5) or persistent MH without RRD (n = 5), in a university Hospital. A 3 or 4 mm diameter disc of lAM, stained with 0.06% trypan blue, was inserted with a catheter through a sclerotomy and positioned over the MH. Gas or silicone-oil tamponade was used. At 1 year, the main outcome was anatomic success defined as complete MH closure. Secondary outcomes were best corrected visual acuity (BCVA) recovery, changes in ellipsoid zone (EZ) and external limiting membrane (ELM) defects, complications. Mean follow-up was 13.8 ± 2.9 months (range, 12-18). RESULTS: Mean baseline data were minimum and maximum diameters, respectively, 945 ± 330 and 1507 ± 717 µm; axial length 26.58 ± 3.38 mm; and number of prior surgeries 1.4 ± 0.96. At 1 year, anatomic success was achieved in eight eyes (80%), and two had reduced diameter of MH. All RRDs were reattached without recurrence. Mean logMAR BCVA improved from 1.92 ± 0.58 to 1.17 ± 0.57 (p < 0.001), with nine eyes (90%) achieving ≥0.3 logMAR improvement. Mean EZ and ELM defects decreased (p = 0.004, p = 0.003, respectively). Postoperative complications were RRD (n = 1) reattached by subsequent surgery, lAM slightly retracted under silicone (n = 1), foveal atrophy after early lAM displacement (n = 1). CONCLUSION: A 1-year follow-up highlighted that epiretinal large discs of blue-stained lAM can help safely close refractory MHs, and provide satisfactory visual recovery.

Detection of refractive photokeratectomy traces during eye banking: impossible with organ culture but possible with an active storage machine: case report.

The detection of corneas operated on for refractive surgery [LASIK or photorefractive keratectomy (PRK)] will become a major concern for eye banks in the coming years because this surgery is often forgotten during the interview with the deceased's relatives. We present here 2 corneas operated on with PKR and stored successively in organ culture (OC) and in the active storage machine (ASM) that restores intraocular pressure, restores the cornea to its original shape, respects transparency and incorporates non-invasive controls. The 2 corneas of a 49-year-old donor operated 17 years earlier by PRK for -2 and -3 diopters myopia were stored in OC for 14 days and then placed in ASM for 48 h. Thickness map and OCT topography were performed under the 2 storage conditions, histology and electron microscopy were then performed. Traces of PRK remained unnoticed in OC while they were evident in ASM with central epithelial anomaly, central thinning and flattening of central keratometry shown by OCT. Histology and ultrastructure confirmed the absence of Bowman's membrane in the center. By placing the cornea under physiological conditions, and in particular by triggering its deswelling and by restoring its natural curvature, the ASM allows effective detection of subtle refractive surgery traces like those present after PRK.

Tolerance to Light of Patients Suffering From Infectious Keratitis.

PURPOSE: With very photophobic patients, the advantages of red or near infrared light to develop new ophthalmology imaging devices seem obvious: no or little glare, possibility of long signal integration, no phototoxicity, and lesser autofluorescence of ocular tissues. Nevertheless, in this range, the shortest possible wavelength facilitates signal detection. The aim of this study was, thus, to determine the maximal irradiance tolerated with 6 wavelengths: 2 red, 2 far red, and 1 near infrared lights to determine the shortest wavelength well tolerated by patients, in comparison with the standard cobalt blue light of ophthalmology slitlamp. METHODS: An interventional, monocentric, single-group assignment study was conducted on 30 eyes of 30 patients with infectious keratitis. Thanks to a customized machine, the photophobic eye was exposed to the 6 lights with increasing intensity. The patients switched off the light when the discomfort was too elevated. The maximal cumulative irradiance possible at 482, 650, 675, 700, 750, and 800 nm were 171, 689, 759, 862, 920, and 889 mW/cm, respectively. RESULTS: The maximal cumulative irradiance tolerated by patients increased significantly with wavelength (P < 0.001), but the difference was not significant between each increment: red at 675 nm gave a significantly higher cumulative irradiance than blue at 482 nm; red at 700 nm did not provide significant gain compared with 675 nm; and far red at 750 nm still provided additional gain compared with 700 nm, but no significant gain was observed between 750 and 800 nm. The shortest wavelengths were stopped more quickly, and more than 50% of patients reached the maximum irradiance delivered by the source at 750 and 800 nm. CONCLUSIONS: We demonstrate that a light source at 750 and 800 nm can be used for ophthalmic imaging with good tolerance in photophobic patients. CLINICAL TRIAL REGISTRATION: NCT03586505.

Using Optical Quality Analysis System for predicting surgical parameters in age-related cataract patients.

The Optical Quality Analysis System (OQAS, Visiometrics) provides objective measurements of image formed onto retina, by combining quantification of ocular media transparency and of optical aberrations. In order to evaluate its contribution in the assessment of age-related cataract, we conducted a monocentric clinical study to determine the relationships between clinical grading of lens opacity, OQAS parameters, and parameters required for cataract surgery by phacoemulsification with ultrasound (called "phacodynamics"). Clinical parameters were: best-corrected visual acuity (BCVA, expressed as Log of minimal angle resolution (logMAR)) and the lens opacity classification system III (LOCS III) as a gold standard determined by two independent observers who graded total cataract and nuclear, cortical and posterior sub capsular components. The OQAS provided an objective scatter index (OSI), a modulation transfer function (MTF, expressed in cycle per degree (cpd)) and a Strehl ratio (SR) used as an aberration marker. Patients were operated on by the same surgeon using a phacoemulsification machine that provided the cumulative dissipated energy (CDE) and total ultrasound time (US time) necessary to extract the lens. Patients with poor compliance, corneal or retinal diseases impairing OSI, or who required surgical settings variation, were excluded. Twenty-one eyes of 21 patients aged 76±8 years were analyzed. They were 11 pure nuclear, 3 pure cortical, and 7 mixed cataracts. Mean LOCS III and OSI were respectively: 4.86 ±2.03 and 6.12 ±3.07 (mean±SD). Medians (10°-90° percentiles) were: for BCVA 0.30 (0.10-0.70) logMAR, for MTF cutoff 9.31 (1.54-30.57) cpd, for SR 0.071 (0.042-0.146), for CDE 8.04 (5.74-23.29) and for US time 58 (39-116) seconds. LOCS III was significantly correlated (spearman r, rs) with BCVA (rs = 0.561, p = 0.008), CDE (rs = 0.457, p = 0.038) and US time (rs = 0.647, p = 0.002). The three OQAS parameters significantly correlated (all rs ≥ 0.526, p<0.05) with BCVA, and LOCS III grading, but the strongest correlations were found with OSI for cortical components and with MTF for nuclear components: only OSI may be used objectively to assess the effect of cortical components on optical quality, and MTF cutoff-integrating scattering and aberrations-seems the best objective parameter for clinical assessment of nuclear cataracts. The three OQAS parameters were also significantly correlated (rs) with CDE, and with US time only for pure nuclear cataracts: OSI had the strongest correlations with phacodynamics (rs = 0.693, p = 0.022 with CDE and rs = 0.703, p = 0.019 US time). OSI increased with cortical components not requiring higher CDE. When measured in optimal conditions (good compliance, no retinal or ocular surface or tear film diseases), the three OQAS parameters are complementary for objective grading of cataract. In the future, they may help to optimize surgical parameters, especially energy distribution, in femtosecond laser assisted cataract surgery.

Corneal donation for research versus for transplantation: A-year prospective study of acceptance rates in a French University Hospital.

Fresh corneal donation is essential for basic and preclinical research, but more unknown to public and the medical teams than donation for transplantation: it may raise concerns. We prospectively compared the acceptance rates and the characteristics of targeted corneal donation for research versus donation for transplantation during one year. The Agence de la Biomédecine authorized us to procure fresh corneas targeted for research, only from the donors with medical contraindications for transplantation, in order not to increase grafts shortage. Three nurses from the hospital coordination team of Saint-Etienne University Hospital, obtained consent for research and transplantation in parallel, screening all intra-hospital deaths cases, following standard protocol to check no refusal from families, despite the French opt-out system. They contacted 127 families for research and 244 for transplantation, in 71% of cases by telephone. Consent was obtained in 62% of cases for research and 54% for transplantation (P = 0.135). The main contraindication for transplantation was the cognitive disorders (66%) followed by the blood cancers (8%). This new specific activity, providing new source of fresh corneas for research immediately usable without any eyebank storage steps, didn't reduce the number of corneas procured for transplantation versus previous years (P = 0.998). Donors in the research group were 10 years older (P<0.001) without difference regarding endothelial cell quality (P = 0.071), allowing maximal clinical relevance for protocols using these fresh human scientific corneas provided by targeted donation.

Innovative corneal active storage machine for long-term eye banking.

Optimal ex vivo corneal storage in eye banks is crucial to increase both the number of corneas suitable for graft and their intrinsic quality, mainly the number of viable endothelial cells, which dictates graft survival in recipients. With both passive storage methods used worldwide (short-term cold storage in the United States, long-term organ culture in Europe), significant endothelial cell loss is inevitable. Here we show that, with an active storage machine, also called a bioreactor, which restores 2 fundamental physiological parameters, intraocular pressure and medium renewal, endothelial cell survival is improved by 23% compared with organ culture after 4 weeks' storage. Also observed in the bioreactor is a 4-fold higher expression of Na+ /K+ ATPase, which supports one of the major endothelial cell pumping functions. In addition, corneas remain thin and transparent, so they are suitable for surgery at any time. This new active eye banking method may help to reduce the severe global scarcity of donor corneas.

Transplantation Blues: Inadvertent Staining of Amyloid Deposits With Trypan Blue.

PURPOSE: To describe inadvertent persistent staining of stromal amyloid deposits by trypan blue (TB) after penetrating keratoplasty (PK) and Descemet membrane endothelial keratoplasty (DMEK) performed in patients with corneal amyloidosis. METHODS: Case series of patients with corneal amyloidosis in whom intraoperative TB was used. RESULTS: One patient, hospitalized for acute rejection 6 weeks after DMEK, presented with an intense blue staining of small, spindle-shaped structures in the anterior half of the cornea. DMEK had been performed for endothelial failure of a previous PK procedure done 13 years earlier for advanced lattice corneal dystrophy (LCD). After 6 months, the stromal blue tattoo persisted with impaired visual acuity, and PK was performed. Blue-stained structures were amyloid deposits characteristic of LCD recurrence. In parallel, among 85 consecutive triple procedures (PK + cataract + intraocular lens [IOL]) performed over 7 years, in which TB was used, only patients with LCD (n = 18 eyes in 17 patients) or presumed secondary amyloidosis due to chronic inflammation (n = 1), presented an isolated intense blue ring of the graft-host interface. This persisted up to 7 years with no clinical consequence. CONCLUSIONS: TB can stain corneal amyloid deposits. After PK, staining is limited to the recipient peripheral cornea and has no apparent clinical consequence. However, during DMEK performed after a failed PK, TB stains fibrils accumulated during slow LCD recurrence and scattered on the whole graft. The long-term staining duration indicates strong interactions between TB and amyloid.

Immunosuppression by a subconjunctival implant releasing dexamethasone in a rabbit model of penetrating keratoplasty.

AIMS: To evaluate the efficacy of a subconjunctival dexamethasone-releasing implant in preventing rejection of penetrating keratoplasty (PK) in an animal model. METHODS: Twenty-two rabbits underwent allogenic PK. After randomisation, they received either a 700 µg dexamethasone implant under the conjunctiva at the end of surgery (n=10), one dexamethasone 1 mg/mL eye-drop thrice daily (n=6) or a placebo thrice daily (n=6). The suture was left in place. Animals were observed weekly by slit-lamp and optical coherence tomography with quantification of transparency, neovascularisation and central corneal thickness (CCT). At 5-6 weeks, they were euthanised for histology. The residual dexamethasone concentration in ocular tissues was measured with an ultra-performance liquid chromatography-tandem mass spectrometer. RESULTS: Placebo group: early neovascularisation was systematic, penetrating the graft by 270-360° at 5-6 weeks. Rejection occurred in 50% of cases. Eye-drop and implant groups: similar course without rejection at 6 weeks and normal CCT. Neovascularisation was observed in 5/6 rabbits in the eye-drop group and in 6/8 in the implant group, with two cases of new vessels penetrating the graft from week 3. Neovascularisation scores did not differ significantly between the two treatments and were significantly lower than for the placebo. Histology was in agreement in all cases. Implants disappeared after 3-5 weeks. No local side effect was observed. Tissue concentrations were all higher at day 8 (n=2) in the implant group than in the eye drop group and lower at 6 weeks (n=8). CONCLUSIONS: In this PK model characterised by a high rejection rate, a subconjunctival dexamethasone implant was for 6 weeks as effective as the topical form in preventing allograft rejection.

Comparison of four methods of surface roughness assessment of corneal stromal bed after lamellar cutting.

Corneal lamellar cutting with a blade or femtosecond laser (FSL) is commonly used during refractive surgery and corneal grafts. Surface roughness of the cutting plane influences postoperative visual acuity but is difficult to assess reliably. For the first time, we compared chromatic confocal microscopy (CCM) with scanning electron microscopy, atomic force microscopy (AFM) and focus-variation microscopy (FVM) to characterize surfaces of variable roughness after FSL cutting. The small area allowed by AFM hinders conclusive roughness analysis, especially with irregular cuts. FVM does not always differentiate between smooth and rough surfaces. Finally, CCM allows analysis of large surfaces and differentiates between surface states.

Handheld In Vivo Reflectance Confocal Microscopy for the Diagnosis of Eyelid Margin and Conjunctival Tumors.

Importance: The clinical diagnosis of conjunctival and eyelid margin tumors is challenging, and new noninvasive imaging techniques could be valuable in this field. Objective: To assess the diagnostic accuracy of handheld in vivo reflectance confocal microscopy (IVCM) for the diagnosis of eyelid margin and conjunctival tumors. Design: A prospective observational study was conducted at University Hospital of Saint-Etienne from January 2, 2011, to December 31, 2016 (inclusion of patients until December 31, 2015, and follow-up until December 31, 2016). A total of 278 consecutive patients with eyelid margin or conjunctival lesions were included. Conjunctival lesions were diagnosed with a conventional clinical examination using a slitlamp and by handheld IVCM. Final diagnoses were established by histopathologic examination for 155 neoformations suspicious for being malignant through clinical and/or IVCM examination that were excised and on follow-up of 12 months or longer for the remaining 140 lesions. Main Outcomes and Measures: Sensitivity, specificity, and positive and negative predictive values for malignant tumors of the conjunctiva and eyelid margin were calculated using clinical examination with slitlamp and handheld IVCM. Results: In the 278 patients (136 [48.9%] females; mean [SD] age, 59 [21] years), a total of 166 eyelid margin and 129 conjunctival lesions were included in the analysis. Of the 155 excised neoformations with a histopathologic diagnosis, IVCM showed higher sensitivity compared with clinical examination conducted with the slitlamp for malignant tumors of the eyelid margin (98% vs 92%) and conjunctiva (100% vs 88%). The specificity for malignant eyelid margin tumors was higher for IVCM than for slitlamp examination (74% vs 46%), but slightly less for malignant conjunctival tumors (78% vs 88%). Analysis of all neoformations (155 excised and 140 in follow-up) confirmed these differences in the diagnostic accuracy of the clinical examination and IVCM. The presence of hyperreflective Langerhans cells mimicking malignant melanocytes was the main cause for misdiagnosis of malignant conjunctival tumors with IVCM. Conclusions and Relevance: Handheld IVCM could be a useful tool for the identification of malignant conjunctival tumors. Further studies are required to confirm the usefulness of this device and identify possible features that can differentiate Langerhans cells from malignant melanocytes to prevent the misdiagnosis of melanoma using IVCM.

Longitudinal study of retinal status using optical coherence tomography after acute onset endophthalmitis following cataract surgery.

PURPOSE: To analyse the macula imaged with optical coherence tomography (OCT) in patients treated for acute postcataract endophthalmitis. METHODS: Patients presenting with acute postcataract endophthalmitis were included in this observational and multicentre study from January 2008 to December 2011. We recorded the following OCT data at the 3, 6 and 12-month visits: the central macular thickness, the perifoveal macular thickness, the central foveal point thickness and abnormalities of the outer retina, the macula and vitreoretinal interface. RESULTS: 46 patients were included in the OCT analysis. From month 3 to 12, epiretinal membrane (ERM) prevalence increased from 26% to 39%, vitreomacular traction prevalence decreased from 12% to 6%, non-tractional macular oedema (ME) prevalence varied between 7% and 13%. Only macular thinning remained stable at 10%. At month 12, a significant correlation was found between non-tractional ME and capsular rupture (at the time of cataract extraction, p=0.03). Eyes with an ERM exhibited increased central macular thickness (p=0.001) and lower visual acuity (VA) (p=0.02) at M12 in comparison to the group with normal macula. OCT analysis showed a significant association between ERM and the alteration of the ellipsoid band (p=0.02), as well as the external limiting membrane (ELM, p=0.07) at M12. CONCLUSIONS: ERM and ME were the main macular abnormalities diagnosed after 1 year of follow-up, associated with VA less than or equal to 20/40 in 50% of the cases. Ultrastructural abnormalities of the ELM and the ellipsoid band were frequently observed in those patients.

'En face' ex vivo reflectance confocal microscopy to help the surgery of basal cell carcinoma of the eyelid.

BACKGROUND: Ex vivo confocal microscopy is a recent imaging technique for the perioperative control of skin tumour margins. Up to date, it has been used in the fluorescence mode and with vertical sections of the specimen margins. The aim of this study was to evaluate its use in the reflectance mode and with a horizontal ('en face') scanning of the surgical specimen in a series of basal cell carcinoma of the eyelid. DESIGN: Prospective consecutive cohort study was performed at the University Hospital of Saint-Etienne, France. PARTICIPANTS: Forty-one patients with 42 basal cell carcinoma of the eyelid participated in this study. METHODS: Basal cell carcinomas were excised with a 2-mm-wide clinically safe margin. The surgical specimens were analysed under ex vivo confocal microscopy in the reflectance mode and with an en face scanning in order to control at a microscopic level if the margins were free from tumour invasion. Histopathogical examination was later performed in order to compare the results. MAIN OUTCOME MEASURES: Sensitivity and specificity of ex vivo confocal microscopy for the presence of tumour-free margins. RESULTS: Ex vivo confocal microscopy results were consistent with histopathology in all cases (tumour-free margins in 40 out of 42 samples; sensitivity and specificity of 100%). CONCLUSIONS: Ex vivo confocal microscopy in the reflectance mode with an 'en face' scanning can control tumour margins of eyelid basal cell carcinomas and optimize their surgical management. This procedure has the advantage on the fluorescent mode of not needing any contrast agent to examine the samples.

Cutting and Decellularization of Multiple Corneal Stromal Lamellae for the Bioengineering of Endothelial Grafts.

Purpose: Engineered corneal endothelial grafts able to provide numerous functional endothelial cells for the restoration of corneal transparency would be a worthwhile way of replacing donor tissue, which is extremely scarce. The grafts are simply constructed: a biocompatible thin and transparent carrier colonized by a monolayer of cultured endothelial cells (ECs). Here we describe a process able to obtain appropriate carriers by recycling human corneas unsuitable for graft in their original state, but liable to provide multiple thin lamellae when cut with a femtosecond laser as used in refractive surgery. Methods: We selected a robust method of stromal decellularization. To demonstrate that neither this process nor long-term storage hindered cell adherence, lamellae were endothelialized with an EC line. Results: The constructs achieved up to very high EC density (the main quality criterion for regular donor corneas) while remaining transparent and thin. We verified that they could be inserted in the anterior chamber of a human eye, like a conventional endothelial graft. Human decellularized cornea will likely be directly compatible with the recipient cornea and comply with the requirements of health regulatory authorities. Conclusions: This study demonstrates that thin human corneal lamellae could have high potential as carriers in next-generation therapy for endothelial dysfunctions.