THREE-DIMENSIONAL RETINAL DISPLACEMENT BEFORE AND AFTER MACULAR PUCKER SURGERY.

PURPOSE: To measure the coronal and sagittal retinal displacement before and after surgery for epiretinal membranes in InfraRed horizontal foveal sections and optical coherence tomography scans and describe displacement tridimensionality, vision loss, and metamorphopsia. METHODS: Retrospective series with greater than 6-month average follow-up before and after surgery. The record included best-corrected visual acuity, optical coherence tomography, M-charts, and InfraRed retinography. Overall, pre- and postoperative coronal and sagittal retinal displacement across the entire field, concentric circles at 0.5-, 1.5-, and 4.5-mm radii, and the central horizontal and vertical meridian were calculated as the optical flow of consecutive images. RESULTS: This study comprised 10 patients (4 men, 6 women), with 22.7 ± 25.2 months follow-up before surgery and 16.2 ± 7.3 months after. Best-corrected visual acuity reduced before surgery (0.15 ± 0.67 logarithm of minimum angle of resolution to 0.38 ± 0.85 logarithm of minimum angle of resolution; P < 0.05) and increased afterward (0.086 ± 0.61 logarithm of minimum angle of resolution; P = 0.003). Preoperative coronal displacement was 30.1 ± 29.1 µm versus 67.0 ± 23.4 µm after (P = 0.002). Sagittal retinal displacement was 140.9 ± 84.6 µm before surgery, 339.7 ± 172.5 µm after (P = 0.017), and 357.6 ± 320.8 µm across the entire follow-up. Preoperative best-corrected visual acuity decreases correlated with the foveal coronal displacement. Vertical metamorphopsia correlated with the average coronal displacement within a 4.5-mm radius. Pre- and postoperative sagittal displacement correlated with horizontal metamorphopsia (P = 0.006 and P = 0.026). Postoperative sagittal displacement correlated with postoperative best-corrected visual acuity (P = 0.026) and foveal thickness (P = 0.009). CONCLUSION: This study confirms that postoperative displacement is greater than preoperative and that sagittal displacement is greater than coronal and correlates with best-corrected visual acuity and metamorphopsia changes.

TLR2 and TLR4 Are Expressed in Epiretinal Membranes: Possible Links with Vitreous Levels of Complement Fragments and DAMP-Related Proteins.

Previous studies reported the expression of toll-like receptors (TLRs), merely TLR2 and TLR4, and complement fragments (C3a, C5b9) in vitreoretinal disorders. Other than pathogens, TLRs can recognize endogenous products of tissue remodeling as damage-associated molecular pattern (DAMPs). The aim of this study was to confirm the expression of TLR2 and TLR4 in the fibrocellular membranes and vitreal fluids (soluble TLRs) of patients suffering of epiretinal membranes (ERMs) and assess their association with disease severity, complement fragments and inflammatory profiles. Twenty (n = 20) ERMs and twelve (n = 12) vitreous samples were collected at the time of the vitrectomy. Different severity-staged ERMs were processed for: immunolocalization (IF), transcriptomic (RT-PCR) and proteomics (ELISA, IP/WB, Protein Chip Array) analysis. The investigation of targets included TLR2, TLR4, C3a, C5b9, a few selected inflammatory biomarkers (Eotaxin-2, Rantes, Vascular Endothelial Growth Factor (VEGFA), Vascular Endothelial Growth Factor receptor (VEGFR2), Interferon-γ (IFNγ), Interleukin (IL1ß, IL12p40/p70)) and a restricted panel of matrix enzymes (Matrix metalloproteinases (MMPs)/Tissue Inhibitor of Metallo-Proteinases (TIMPs)). A reduced cellularity was observed as function of ERM severity. TLR2, TLR4 and myD88 transcripts/proteins were detected in membranes and decreased upon disease severity. The levels of soluble TLR2 and TLR4, as well as C3a, C5b9, Eotaxin-2, Rantes, VEGFA, VEGFR2, IFNγ, IL1ß, IL12p40/p70, MMP7 and TIMP2 levels were changed in vitreal samples. Significant correlations were observed between TLRs and complement fragments and between TLRs and some inflammatory mediators. Our findings pointed at TLR2 and TLR4 over-expression at early stages of ERM formation, suggesting the participation of the local immune response in the severity of disease. These activations at the early-stage of ERM formation suggest a potential persistence of innate immune response in the early phases of fibrocellular membrane formation.

RETINAL TECTONICS AFTER MACULAR PUCKER SURGERY: Thickness Changes and En Face Displacement Recovery.

PURPOSE: To study visual function, retinal layer thickness changes, and tangential displacement after pars plana vitrectomy for epiretinal membrane. METHODS: Retrospective series of patients undergoing pars plana vitrectomy for epiretinal membrane, with 6-month follow-up including best-corrected visual acuity, optical coherence tomography, M-charts, epiretinal membrane grading, and infrared fundus photograph at time 0 (T0, preop) at months 1 (T1), 3 (T3), and 6 (T6) postop (±1 week). Retinal layer thickness and tangential ( en face ) retinal displacement between successive times for the entire retinal surface and the central horizontal and vertical meridian were also measured. En face displacement was calculated as optical flow of consecutive images. RESULTS: Average best-corrected visual acuity improved from 0.28 ± 0.08 logarithm of Minimum Angle of Resolution at T0 to 0.16 ± 0.25 at T6 ( P = 0.05), best-corrected visual acuity improvement correlated with best corrected visual acuity (BCVA) at T0 ( P < 0.001). Vertical metamorphopsia decreased from 1.33° ± 0.70° at T0 to 0.82° ± 0.69° at T6 ( P < 0.05). Foveal thickness reduced from 453 ± 53 µ m at T0 to 359 ± 31 µ m at T6 ( P < 0.05) and reduction correlated with best-corrected visual acuity improvement ( P < 0.05). Foveal layers decreased ( P < 0.05) in all cases. The mean en face deformation was 155.82 ± 50.17 µ m and mostly occurred in the first month: T0-T1 displacement was 83.59 ± 30.28 µ m, T1-T3 was 36.28 ± 14.45 µ m, while T3-T6 was 39.11 ± 22.79 µ m ( P < 0.001) on average. Perifoveal and parafoveal deformation correlated with optical coherence tomography foveal thickness reduction at all time intervals (1, 3, and 6 months: P < 0.01). CONCLUSION: Epiretinal membrane peeling affects all retinal layer thickness and results in new force balance across the entire retina and tangential displacement. Both en face and in-depth changes correlate with visual function.

TANGENTIAL RETINAL DISPLACEMENT INCREASES AFTER MACULAR PUCKER SURGERY: An Apparent Nonsense.

PURPOSE: To measure the tangential retinal displacement and vision before and after macular pucker surgery and study if pars plana vitrectomy with epiretinal membrane peeling allows the reconstitution of previous anatomy or else it results in a different configuration. METHODS: Retrospective series of patients undergoing pars plana vitrectomy for epiretinal membrane, with >6-month follow-up before and after surgery, complete with best-corrected visual acuity, optical coherence tomography, M-Charts, and infrared retinography. Tangential retinal displacement between earliest visit (T E ), time of surgery (T 0 ), and latest available visit (T L ) of the examined retina, concentric circles at 0.5, 1.5, and 4.5 mm radii, and the central horizontal and vertical meridians were measured. Tangential displacement was calculated as the optical flow of consecutive infrared photographs. RESULTS: The study comprised 32 patients: 15 men and 17 women. Average preoperative and postoperative follow-up were 23.4 ± 27.9 months and 19.2 ± 11.8 months, respectively. Best-corrected visual acuity reduced before surgery (0.69 ± 0.16 Snellen to 0.46 ± 0.17; P < 0.001) and increased after (0.866 ± 0.16 Snellen; P < 0.001). Horizontal and vertical metamorphopsia increased between before surgery but only horizontal metamorphopsia significantly reduced after. Average tangential displacement before surgery was 35.6 ± 29.9 µ m versus 56.6 ± 41.3 µ m after ( P = 0.023). Preoperative and postoperative displacement within the fovea was less than over the entire area ( P < 0.001). CONCLUSION: Retinal tangential displacement between diagnosis and surgery (T E - T 0 ) is less than the displacement occurring after surgery (T 0 - T L ). Postoperative displacement does not represent the restoration of the anatomy existing before the disease ensued but rather the resulting equilibrium of newly deployed forces.

Biomarker Signature in Aqueous Humor Mirrors Lens Epithelial Cell Activation: New Biomolecular Aspects from Cataractogenic Myopia.

Inflammatory, vasculogenic, and profibrogenic factors have been previously reported in vitreous (VH) and aqueous (AH) humors in myopic patients who underwent cataract surgery. In light of this, we selected some mediators for AH and anterior-capsule-bearing lens epithelial cell (AC/LEC) analysis, and AH expression was correlated with LEC activation (epithelial-mesenchymal transition and EMT differentiation) and axial length (AL) elongation. In this study, AH (97; 41M/56F) and AC/LEC samples (78; 35M/43F) were collected from 102 patients who underwent surgery, and biosamples were grouped according to AL elongation. Biomolecular analyses were carried out for AH and LECs, while microscopical analyses were restricted to whole flattened AC/LECs. The results showed increased levels of interleukin (IL)-6, IL-8, and angiopoietin-2 (ANG)-2 and decreased levels of vascular endothelium growth factor (VEGF)-A were detected in AH depending on AL elongation. LECs showed EMT differentiation as confirmed by the expression of smooth muscle actin (α-SMA) and transforming growth factor (TGF)-ßR1/TGFß isoforms. A differential expression of IL-6R/IL-6, IL-8R/IL-8, and VEGF-R1/VEGF was observed in the LECs, and this expression correlated with AL elongation. The higher VEGF-A and lower VEGF-D transcript expressions were detected in highly myopic LECs, while no significant changes were monitored for VEGF-R transcripts. In conclusion, these findings provide a strong link between the AH protein signature and the EMT phenotype. Furthermore, the low VEGF-A/ANG-2 and the high VEGF-A/VEGF-D ratios in myopic AH might suggest a specific inflammatory and profibrogenic pattern in high myopia. The highly myopic AH profile might be a potential candidate for rating anterior chamber inflammation and predicting retinal distress at the time of cataract surgery.

Silicone Oil Tamponade Removal: Which Technique Is More Effective? An X-Ray Photoemission Spectroscopy Study.

Purpose: To compare the efficacy of two surgical techniques used to remove silicone oil (SiO) emulsion tamponade after pars plana vitrectomy: triple air-fluid exchange (AFX) and balanced salt solution lavage (BSSL). Methods: X-ray photoemission spectroscopy measured silicon content of the dry residue of fluid samples taken during AFX and BSSL. Ten patients underwent AFX and five BSSL. Three fluid samples were taken per patient, and the dry residue of 10 drops per sample were analyzed. A fluid sample from a patient who never received SiO tamponade was also analyzed to set a "blank" reference sample. Results: Patients' demographics showed no significant difference. Sample 1 of the two groups contained comparable silicon content while samples 2 and 3 of the AFX group contained significantly more silicon than that of the BSSL group (15.0 ± 0.1 and 12.0 ± 0.9 for the AFX group vs. 10.7 ± 1.4 and 5.2 ± 0.6 for the BSSL group, respectively; P < 0.05). The cumulative amount of silicon in the three successive samples was also significantly higher for the AFX group (42.3 ± 1.6 vs. 32 ± 2; P < 0.0001). The average silicon content ratio of consecutive samples was significantly higher for the AFX group compared to the BSSL group (0.90 ± 0.01 vs. 0.58 ± 0.06; P = 0.006). Conclusions: Triple AFX removed more silicon than triple lavage. The eye wall actively interacts with silicon emulsion retaining silicon content rather than behaving as a neutral container. Translational Relevance: Triple air-fluid exchange removed more silicon than BSS lavage. Neither technique behaved as a well-mixed box dilution, suggesting the eye walls actively retain emulsion and a dynamic equilibrium is established between silicon dispersion and the eye wall surface.

Phacoemulsification Tip Elongation Under Standardized Resistance: An Objective Measure of Human Crystalline Lens Hardness.

Purpose: To establish a correlation between phacoemulsification tip normalized driving voltage (NDV) and crystalline lens hardness and use it as an objective measure of lens hardness. The study used a phaco tip equipped with previously validated elongation control adjusting the driving voltage (DV) to produce invariant elongation regardless of resistance. Methods: The laboratory study measured the mean and maximum DV of the phaco tip immersed in glycerol-balanced salt solution and correlated the DV with the kinematic viscosity at 25, 50, and 75 µm tip elongation. The NDV were obtained by dividing the DV in glycerol by the DV in the balanced salt solution. The clinical arm of the study recorded DV of 20 consecutive cataract surgeries. The correlation of mean and maximum NDV to Lens Opacities Classification System (LOCS) III classification, patient's age and effective phaco time were evaluated. Results: The mean and maximum NDV correlated with the kinematic viscosity of the glycerol solution (P < 0.001 in all cases). Mean and maximum NDV during cataract surgery correlated with patients' age, effective phaco time, LOCS III nuclear color, and nuclear opalescence (P < 0.001 in all cases). Conclusions: When a feedback algorithm is running, DV variation strictly correlates with encountered resistance in glycerol solutions and real-life surgery. NDV significantly correlates with the LOCS classification. Future developments might include sensing tips that react to lens hardness in real time. Translational Relevance: The study correlates for the first time phaco tip DV and crystalline lens mechanical properties, establishing an objective and reliable measure of lens hardness. This may lead to smart phaco tips reacting to cataract hardness change in real time and sparing ultrasound dispersion.

Superficial and Deep Capillary Plexuses: Potential Biomarkers of Focal Retinal Defects in Eyes Affected by Macular Idiopatic Epiretinal Membranes? A Pilot Study.

Inner macular layers are the most involved in the retinal distortion caused by idiopathic epiretinal membrane (iERM). They represent the anatomical structures in which the superficial (SCP) and deep (DCP) capillary plexus are embedded. We quantified flow signal (FS) in these capillary plexuses using Swept Source OCT angiography to identify possible markers for postoperative outcome. The software ImageJ was used to quantify the FS in a 150 µm radius area around each point analyzed by MAIA microperimeter. In 16 patients with unilateral iERM, focal light sensitivity (FLS) in the para- and perimacular areas was measured to evaluate macular function in 24 points overlapping macular plexuses and compared with normal fellow eyes (FEs). t-Test for independent samples iERM eyes (iERMEs) vs. fellow eyes (FEs) and Pearson correlation coefficient of FS vs. FLS in each point were calculated. A level of p < 0.05 was accepted as statistically significant. As a whole, FLS was significantly higher in FEs vs. ERMEs (p < 0.001); FS in both SCP and DCP was not significantly different between ERMEs and FEs (p = 0.827, p = 0.791). Correlation in focal retinal areas between FLS and FS in ERMEs was significant in SCP (p = 0.002) and not significant in DCP (p = 0.205); in FEs was significant in both SCP (p < 0.001) and DCP (p = 0.022). As previously described, these defective areas were located mainly in sites of distortion of retinal layers; therefore, it can be hypothesized that a focal change in FS, occurring mostly in SCP, could be involved in the onset of the functional defect.

Branch retinal artery occlusion caught in the act by an optical coherence tomography angiography image: case report.

BACKGROUND: Retinal artery occlusion is a vascular entity caused by the temporary blockage of retinal arterioles. CASE PRESENTATION: We present the case of a 57-year-old woman a partial visual loss in the right eye due to a cilioretinal artery occlusion. Ophthalmoscopy revealed a focal area of retinal whitening superior to the optic nerve in the right eye, while the left eye was within the limit. Retinal imaging, in particular optical coherence tomography angiography (OCTA), showed a capillary drop out of the superficial capillary plexus and the corresponding b-scan showed a round hyporeflective grey dot (optical empty) corresponding to the dark grey spot on the enface view at the level of the retinal whitening area. CONCLUSION: Although the images did not allow the differentiation between vasospasm or retinal emboli, the OCTA imaging might help to identify and to caught in the act the specific region causing the retinal impairment. Also, the possible formation of small microcavity should be considered in case with branch retinal artery occlusion. The use of this new imaging technology might help to evaluate the efficacy of the therapy in vivo.

Silicone Oil Tamponade-Retina Contact in Highly Myopic Eyes With and Without Encircling Bands: A Computational Fluid Dynamics Study.

Purpose: To investigate the behavior of silicone oil (SiO) at a steady equilibrium and during saccades in pseudophakic highly myopic eyes with posterior staphyloma with and without an encircling band and compare it to behavior in emmetropic eyes. The SiO-retina contact area and shear stress were calculated by computational fluid dynamics. Methods: A numerical model of an emmetropic eye and a myopic eye with and without scleral band underwent a saccade of 50°/0.137 s. The vitreous chamber surface was divided into superior and inferior 180° sectors: lens, pre-equator, post-equator, and macula. SiO-retina contact was evaluated as a function of fill percentages between 80% and 90% for standing, 45° upward tilt, and supine patients. Maximum and average shear stress were calculated. Results: Overall, SiO-retina contact ranged between 40% and 83%; fill percentage varied between 80% and 95%. Neither the encircling scleral band nor the staphyloma significantly affected the SiO-retina contact area, although the presence of a scleral band proved disadvantageous when gazing 45° upward. The inferior retina-SiO contact remained below 40% despite 95% SiO fill. The SS significantly increased at the scleral band indentation and decreased elsewhere. The staphyloma greatly reduced shear stress at the macula. Conclusions: The presence of a myopic staphyloma reduces shear stress at the macula but does not alter SiO-retina contact significantly. The apposition of a 360° scleral band may reduce SiO-retina contact at least in some postures and increases the SS at the indentation. Translational Relevance: Assessing SiO-retina contact when vitreous chamber geometry changes according to pathologic or iatrogenic modifications allows accurate prediction of real-life tamponade behavior and helps explain surgical outcomes.

Human Vitreous Collagen Fragments Dimension As a Function of Vitrectomy Cut Rate.

Purpose: To study the dimensions and distribution of human vitreous collagen type II fragments collected after vitrectomy performed at varying cut rates and to evaluate if increasing the cut rate produces smaller collagen fragments, thus reducing retinal traction and/or viscosity. Methods: Fluid was collected during core vitrectomies performed for macular surgery at cut rates from 1000 to 16,000 cuts per minute (CPM) and immediately refrigerated. Protein fractions were separated by molecular weight (MW; >100 kDa, 50-100 kDa, 50-30 kDa, 30-10 kDa, and <10 kDa) through centrifugal filters. The Human Collagen II ELISA Kit colorimetric assay was then used to measure the COL2A1 in unfiltered and filtered samples. Results: Vitreous samples collected after vitrectomy performed at 16,000 CPM contained a higher concentration of protein with MW over 100 kDa than at any other cutting frequency (P < 0.01). No significant differences were found in fractions collected with a MW between 50 and 100 kDa. Collagen type II fragments over 100 kDa were significantly more represented than smaller fragments at each cut rate. The proportion of smaller (50-100 kDa) collagen fragments compared with those over 100 kDa was higher at 2000 CPM than at higher cut rates. Conclusions: Vitreous samples collected at different cut rates do not contain a significantly different proportion of collagen type II fragments of the tested MW. The extreme variability of vitreous flow through the cutter port may explain the uncertain predictability of collagen fragment MWs. Translational Relevance: Increasing the cut rate does not produce vitreous fragments of proportionally smaller dimension. It is necessary to achieve an invariant instantaneous flow through the cutter port in order to decrease retinal traction during vitrectomy.

Bilateral optic neuritis as the presenting sign of post SARS-CoV-2 acute disseminated encephalomyelitis.

PURPOSE: to report a case of Acute Disseminated EncephaloMyelitis (ADEM) occurring after documented SARS-Cov2 infection and flu-like disease. OBSERVATION: A 59-years-old woman presented with progressive visual loss and right leg paresthesia started 6 days earlier when CT scan excluded abnormalities. Visual acuity was OU hand motion with bilateral slow pupillary response and unremarkable ocular extrinsic motility while visual field testing showed diffuse bilateral sensitivity reduction. The patient had also right leg paresthesia and reported a 2-weeks flu-like syndrome 15 days earlier, with nausea, diarrhea, anosmia, ageusia, cough. Brain Magnetic Resonance Imaging revealed bilateral optic nerve enhancement, multiple brain and spine lesions. SARS-CoV-2 PCR tested negative on nasal swab and positive on cerebrospinal fluid. Patient's serum tested positive for anti-SARS-CoV-2 IgG, negative for anti-aquaporin-4 and anti-myelin oligodendrocyte glycoprotein antibodies. A diagnosis of suspect ADEM post SARS-CoV-2 infection was made and treatment with high dose intravenous methylprednisolone (with subsequent prednisone tapering) and immunoglobulins started. Ten days later vision improved to 20/30 RE and 20/25 LE and 3 months later to 20/20. CONCLUSION AND IMPORTANCE: ADEM may ensue after SARS-CoV-2 virus infection. High suspicious index and prompt aggressive treatment may result in complete vision restauration.

Influence of anterior capsulorhexis shape, centration, size, and location on intraocular lens position: finite element model.

PURPOSE: To evaluate the influence of anterior capsulorhexis shape, dimension, and eccentricity on intraocular lens (IOL) position. SETTING: Laboratory investigation. DESIGN: Computational model. METHODS: A finite element model of the human crystalline lens capsule and zonule was created and the anterior capsule opened to simulate centered and decentered circular and elliptic rhexis. The model calculated capsular bag stress, IOL rotation, tilt, decentration, and vaulting, related to both capsular landmarks (absolute) and a reference IOL position defined as that obtained with a 5.0 mm circular and centered rhexis. RESULTS: Mean von Mises stress along the IOL major z-axis was significantly higher than that along the perpendicular x-axis in all cases (P < .001), both at the equator and at the rhexis edge. Stress at the equator was always greater than that at the rhexis edge (P < .001) regardless of the rhexis shape and position. As rhexis eccentricity increased, the stress difference between the z- and x-axes increased. Absolute IOL tilt (range 10-1 to 10-7 degrees), decentration (10-3 to 10-7 mm), rotation (10-2 to 10-3 degrees), and vaulting (10-1 mm) were negligible from an optical standpoint, but all of them were significantly greater for decentered rhexis (both round and elliptic) compared with centered (P < .05). CONCLUSIONS: Anterior capsulorhexis irregularity and/or eccentricity increase IOL tilt, decentration, rotation, and vaulting in a numerically significant but optically negligible way. Von Mises stress is much greater at the capsular bag equator compared with the rhexis edge and highly asymmetrically distributed in all cases. Stress asymmetry may influence postoperative biologic processes of capsular bag shrinking and further IOL tilting or decentration.

THE PROPHYLAXIS OF FELLOW-EYE RETINAL DETACHMENT IN STICKLER SYNDROME: A RETROSPECTIVE SERIES.

PURPOSE: To evaluate retrospectively if scleral buckling combined or not to cryopexy reduces fellow-eye retinal detachment (RD) in Stickler syndrome patients who lost their first eye due to RD. METHODS: Retrospective review of 52 Stickler syndrome patients who received a 6-mm wide, 360° encircling scleral buckling. Thirty-nine (75%; Cryo + Group) also received cryo treatment, whereas the reminder 13/52 (25% Cryo - Group) did not. RESULTS: Average follow-up was 15.6 ± 2.41 years. Five patients (5/52; 9.6%) developed a retinal detachment 2.6 ± 0.55 years after prophylactic treatment, respectively, 0/39 patients in the Cryo + Group and 5/13 in the Cryo - Group (P < 0.001). All five RD eyes were successfully reattached through revised episcleral surgery and adjunctive cryo treatment. Postop refraction changed an average -1.9 ± 0.74 diopters and best corrected visual acuity at the end of follow-up was 20/25 (0.1 ± 0.07 logarithm of the minimum angle of resolution), not significantly different from the rest of sample population who did not develop RD in their fellow eye. CONCLUSION: Cryopexy significantly reduced the risk of RD in Stickler syndrome patients undergoing scleral buckling. If RD ensues, the presence of scleral buckling may ease surgical repair and improve final outcome.

Phacoemulsification and nucleic acid-enriched aerosol: considerations from an eye model of cataract simulation.

PURPOSE: The purpose of this study is to investigate whether phacoemulsification can generate aerosolized single-stranded RNA (ssRNA) and retain sequence integrity using an artificial eye model for experimental cataract surgery. METHODS: A simulation of cataract surgery was performed using an anterior chamber eye model filled with an ssRNA probe at different scalar dilutions (kanamycin positive control ssRNA). A plastic conical cage was built over the artificial eye surface of the mock-up. A total of 24 tests (twice reproduced) were performed, and five nitrocellulose strips were placed 15 cm from the artificial surface of the mock-up and used to collect aerosol particles, from each experiment. Phaco-activity was mimicked using a phacoemulsification equipped with a 2.75-mm tip, and strips were removed at the end of the procedure. RNA extraction, reverse transcription, and agarose gel electrophoresis were performed and compared. RESULTS: Strips collected aerosol droplets enriched with ssRNA, mainly at the higher concentrations tested, compared to related untouched standard solutions. Complementary DNA (cDNA) synthesis confirmed the presence of intact ssRNA fragments. As observed from densitometric analysis of resolved RNA in extracted samples and cDNA bands after retro-transcription, lower concentrations of ssRNA were also detected. CONCLUSIONS: As the main output of the study, the phaco-generated aerosol can deliver an intact ssRNA sequence. Since the aerosol can potentially reach the operator's face, any biological agent (virus/bacteria) potentially inside the anterior chamber of a patient undergoing cataract surgery, eventually escaping from biomolecular checks, can be potentially infective for operators. The data reported herein suggest that collective versus individual protective countermeasures should always be encouraged in ocular surgery and should not be restricted to coronavirus disease emergencies.

Inner Macular Changes in Fellow Eye of Patients With Unilateral Idiopathic Epiretinal Membrane.

Purpose: We evaluated a series of fellow eyes (FEs) in patients affected by unilateral idiopathic epiretinal membrane (IERM) with spectral-domain optical coherence tomography (SD-OCT) and OCT angiography (OCT-A) to determine if a previous defect in the inner retina is present before the mechanical damage to the inner limiting membrane (ILM) caused by posterior vitreous detachment. Methods: In patients with IERM (N = 39), ganglion cell layer (GCL) thickness in FEs was assessed with SD-OCT; in a subgroup (N = 25) the vessel density (VD) at the superficial (SCP) and deep capillary plexus (DCP) was assessed with swept-source OCT-A (SS-OCT-A). These values were then compared with 30 age-matched healthy control eyes (CEs). The statistical analyses used SPSS software version 15.0 (SPSS, Inc., Chicago, IL, USA). Data collected underwent 1-way ANOVA. A level of P < 0.05 was accepted as statistically significant. Results: The GCL thickness in the FEs was significantly lower than in CEs, with a significant thinning in all sectors except temporal ones (mean P < 0.001, superior P = 0.0002, superonasal P < 0.001, inferonasal P < 0.001, and inferior P = 0.002). The VD was significantly lower in the FEs in all sectors of SCP (mean P = 0.009, inner ring P = 0.028, and outer ring P = 0.007). Conclusions: GCL and SCP are significantly reduced in the FEs. These data suggest that a vascular defect in the SCP could cause a cellular loss in the inner retina that may determine the cascade events leading to the IERM proliferation; the diagnosis in a preclinical phase could provide a treatment strategy to prevent the progression of the disease.

Computational Fluid Dynamics of Intraocular Silicone Oil Tamponade.

Purpose: To investigate the behavior of silicone oil (SiO) at the steady equilibrium and during saccades and calculate SiO-retina contact, shear stress (SS), and shear rate (SR). Methods: A 24 mm phakic eye mesh model underwent 50°/0.137s saccade. The vitreous chamber compartment was divided into superior and inferior 180° sectors: lens, pre-equator, postequator, and macula. SiO-retina contact was evaluated as a function of fill percentages between 80% and 90% for a standing patient, 45° upward gaze, and supine. SS and SR for 1000 mPa-s (SiO1000) and 5000 mPa-s (SiO5000) silicon oil were calculated. Results: SiO fill between 80% to 90% allowed 55% to 78% retinal contact. The superior retina always kept better contact with SiO, regardless of the fill percentage (P < 0.01). SiO interface thoroughly contacted the macula only in standing position. SS followed a bimodal behavior and was always significantly higher for SiO5000 compared to SiO1000 (P < 0.01) throughout the saccade. The macula suffered the highest mean SS in standing position, while throughout the saccade the average SS was maximum at the SiO-aqueous interface. SR was significantly higher for SiO1000 compared to SiO5000 (P < 0.001). Conclusions: SS on the retinal surface may instantaneously exceed reported retinal adhesiveness values especially at the SiO-aqueous interface and possibly favor redetachment. Despite 90% SiO fill the inferior retina remains extremely difficult to tamponade. Translational Relevance: Accurate assessment of retina-tamponade interaction may explain recurrent inferior retinal redetachment, silicone oil emulsification, and help to develop better vitreous substitutes.

Cataract surgery practice patterns worldwide: a survey.

OBJECTIVE: To report the results of a global survey on cataract practice patterns related to preoperative, intraoperative and postoperative care, surgical setting and personnel allocation. METHODS AND ANALYSIS: An online 28 questions survey was sent to 240 ophthalmologists asking to describe prevailing trends in their institutions across 38 countries and 5 continents. Questions inquired country, institution, surgical volume and setting, anaesthesia, preoperative and intraoperative examination and postsurgical care. Statistical analysis used crosstabs lambda statistics for non-parametric nominal variables. P value less than 0.05 was considered statistically significant. RESULTS: 209/240 (87%) ophthalmologists responded: 38% representing public hospitals, 36% private practices and 26% academic sites; overall surgical volume was between 241 700 and 410 500 cataracts per year. There was a significant correlation between type of institution and surgical volume. Complete results available in online (https://freeonlinesurveys.com/r/W6BcLLxy). CONCLUSION: Cataract surgery related patterns of perioperative care showed significant difference among respondents, regardless to type of institution, surgical volume and country. Many evidence-based procedures are unevenly practiced around the world and some widespread and expensive habits lack solid scientific evidence while consuming enormous amount of resources both monetary and human. There is a need to reach consensus and share evidence-based practice patterns.

Autologous internal limiting membrane transplant for recurrent idiopathic macular holes.

PURPOSE: To report a series of recurrent idiopathic macular holes treated by means of a free autologous internal limiting membrane flap and compare visual and anatomic results to a control group undergoing further internal limiting membrane peeling and novel gas tamponade. METHODS: Retrospective surgical series of 15 consecutive patients receiving autologous internal limiting membrane flap compared to 14 patients operated on for internal limiting membrane peeling enlargement. Autologous internal limiting membrane flap was created after brilliant blue G staining, internal limiting membrane lifting, perfluorocarbon bubble injection and creation of a wide internal limiting membrane free flap translocated underneath perfluorocarbon liquid, to the macular hole bed. Both groups were tamponated with 20% SF6 and positioned face down for 4 h a day for 3 days. RESULTS: Macular hole closed in 14/15 (93.3%) patients of the autologous internal limiting membrane group and 9/14 (64.2%) controls (p < 0.05). Visual acuity increased from 0.05 ± 0.03 to 0.23 ± 0.13 Snellen in the autologous internal limiting membrane group and from 0.05 ± 0.03 to 0.14 ± 0.10 Snellen of controls (p < 0.05 for both). Vision of the autologous internal limiting membrane group improved more than controls at 1 month (p = 0.043) and 3 months (p = 0.045). Inner segment/outer segment interruption at 3 months was smaller in the autologous internal limiting membrane group than controls, reducing from 1230 ± 288 µm at baseline to 611 ± 245 and 547 ± 204 µm at 3 months versus 1196 ± 362, 745 ± 222 and 705 ± 223 µm, respectively (p < 0.05). CONCLUSION: Autologous internal limiting membrane flap can effectively close recurrent idiopathic macular holes with a higher closure rate, smaller residual inner segment/outer segment line interruption and higher visual acuity at 3 months than previous standard of care.

A novel intraocular lens designed for sutureless scleral fixation: surgical series.

PURPOSE: To report a retrospective series of patients implanted with a novel hydrophilic acrylic single-piece intraocular lens (IOL) designed for sutureless scleral fixation (FIL-SSF Carlevale lens, Soleko, Italy) injectable through a 2.2-mm incision. METHODS: Seventy-eight patients with minimum 6-month follow-up were divided into 6 groups: dropped nucleus, luxated IOL, trauma, aphakia, IOL exchange, and Marfan's syndrome. Surgery included peritomy and scleral flap creation at 3 and 9 o'clock position. The IOL was then injected and grasped with 25G forceps through a hole created 2 mm posterior to the limbus underneath the sculped scleral flap. RESULTS: The study included 78 patients (mean age 71.9 ± 12.6 years) and average follow-up 10.2 ± 4.2 months. Average surgery duration was 69.4 ± 26.1 min and vision significantly improved from 0.86 ± 0.56 logMAR to 0.38 ± 0.42 logMAR at 6 months post-operative (p < 0.001). Intraoperative complications included corneal edema, retinal tears, and vitreous bleeding each in 2/78 patients (2.5%); 1/78 (1.3%) localized retinal detachment and 1/78 (1.3%) rupture of one T-shaped IOL harpoon. Post-operative complications included 4/78 (5.1%) cystoid macular edemas, 2/78 retinal tears, 2/78 retinal detachments, 2/78 developed ocular hypertension, and 1/78 corneal decompensation requiring DSAEK. CONCLUSION: The Carlevale lens is designed for sutureless intrascleral fixation and can be successfully used in a variety of indications including difficult trauma cases with good rehabilitation. An implant requires experience and delicate manipulation.