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Purpose: To present a novel optical model explaining why the vast majority of patients with Asteroid Hyalosis (AH) do not perceive any floaters. This changes our understanding of floater perception and undermines the operation mode of YAG laser vitreolysis. Methods: Relying on a previously published model of floater perception based on astronomical equations of a solar eclipse, and on ultrasound images of the vitreous in three eyes with AH, we explain why such patients do not perceive floaters in spite of opaque bodies filling their entire vitreous, to the point of, in severe cases of AH, obscuring the fundus view during ophthalmoscopy. Main outcome measures: Developing an optical model of light rays that can quantify the maximal distance upon which a vitreous floater or opacity will cast a shadow on the retina. Results: Calculations using the proposed model demonstrated that with a 3 mm pupil, for a floater located between 1.5 mm and 2 mm from the retina, its shortest diameter must be > 215 microns and > 286 microns, respectively, to be perceived. Since AH floaters, based on ultrasound imaging, do not exist in the most peripheral 1.5 mm of the vitreous, it becomes understandable why these patients are asymptomatic. Conclusions: Based on the proposed model and our findings, we deduced that even large, degenerative floaters whose width is usually narrower than a large retinal vein (125 microns), must be located very close to the retina and hence are not the floaters that are aimed at when performing YAG laser vitreolysis. We speculate that in successful cases, YAG vitreolysis works by a different mechanism, most likely a shock wave that displaces floaters further away from the retina. Hence, vitreolysis might not necessarily require the laser be aimed at the floaters, as symptomatic floaters may be located in the outer 1.5–2.0 mm of the vitreous body, a very risky zone for YAG laser shots. [ABSTRACT FROM AUTHOR]

Objectives: To assess the mismatch between the clinical observation of vitreous alterations and self-reported symptoms in young patients complaining of symptomatic vitreous opacities (SVO). Methods: The ophthalmic medical records of young patients presenting primarily with SVO were retrospectively evaluated. Symptoms severity was assessed using a questionnaire. The status of the vitreous body was examined with indirect ophthalmoscopy at the slit-lamp and classified according to an ad hoc severity scale. Results: Sixty eyes of thirty otherwise healthy patients (median age: 32.5 (IQR: 29.0–37.0) years old) complaining of SVO (median duration: 38 months; interquartile range: 18–84 months) were enrolled. SVO was rated as severe by 50% of participants, affecting all the activities explored in the questionnaire. Twenty-three patients (76.6%) reported SVO-related depression and/or anxiety, for which eleven patients (36.6%) were or had been using medication. Fifty-eight eyes (96.6%) showed no evidence of (or minimal) vitreous opacity, while two eyes (3.3%) were found to have significant vitreous opacity. No significant inter-gender differences (p > 0.05) and no significant differences (p > 0.05) were found between the severity of vitreous opacity and patients' reported symptoms nor with their psychological status and medication use. Conclusions: Severe discomfort related to the perception of vitreous floaters exists in young patients whose vitreous gel examination is unremarkable or shows only minor alterations. We believe this discrepancy can be explained by optical anisotropy; significant forward-scattering of light, which results in floater symptoms; and reduced back reflection, which limits the clinical observation. [ABSTRACT FROM AUTHOR]

Objective Animal Studied Procedures Results Conclusions To describe morphological features of Megaptera novaeangliae eyes using ultrasonography and histology.A total of 21 globes from 19 M. novaeangliae were used for the study, including two animals with bilateral assessment. Nine stranded animals were found alive, 10 dead.Carcasses were classified according to decomposition state. Globes were assessed ultrasonographically, biometric measurements were taken and then the tissues were sectioned for histological analysis.Seventeen carcasses were classified as decomposition code 2 and two as code 3. Fifteen animals were calves, three juveniles and one adult, twelve males, and five females. The cornea was thinner in the center of the eye and thicker at the periphery. The lens had an oval shape. Fourteen animals showed a structure in the vitreous body which looked triangular and filamentous by ultrasonography and, histologically, originated in the central part of the optic nerve and extended to the posterior region of the lens, composed of connective tissue. The most common abnormalities found by ultrasonograph were retinal detachment (n = 13) and displacement of the lens into the vitreous (n = 4), along with alterations suggestive of hemorrhage, fibrin deposits, and increased echogenicity in the optic nerve (n = 2).An intraocular structure not previously described in cetaceans was found in this investigation; its function remains unknown. Circulatory changes that were evident in the histopathological analysis may be due to the stranding process and raise the need to consider ophthalmic examinations before reintroducing stranded mysticetes. [ABSTRACT FROM AUTHOR]

Background: This study aimed to precisely predict the size and silicone oil injection of a foldable capsular vitreous body (FCVB) via computerized three-dimensional (3D) ocular reconstruction in the treatment of severe retinal detachment in China. Methods: The 3D software Unigraphics NX was applied to determine the volume of the inner cavity with 16–30 mm axial length, assigning the anterior and posterior chambers, the FCVB sizes, and the silicone oil injection volume, and modeling the data between the axial length and the FCVB size. In clinical practice, IOL Master was applied to accurately measure the axial length of the contralateral healthy eye to anchor the anterior-posterior and horizontal diameters of the operated eye in horizontal position CT, and compared with the model to recommend the FCVB size and silicone oil amount, and the clinical effect was validated in cases across five hospitals in China. Results: For the axial length of 16–30 mm, the volume of the inner cavity is 1.2 ml-8.4 ml. FCVB size and silicone oil volume were recommended based on this volume of the inner cavity. Of 253 cases, we noted 11 cases implanted with AV-10P and 1.05 ± 0.21 ml of silicone oil, 41 with AV-12P and 1.58 ± 0.18 ml of silicone oil, 163 with AV-13.5P and 2.48 ± 0.29 ml of silicone oil, 31 with AV-15P and 3.57 ± 0.39 ml of silicone oil, and 7 with AV-17P and 5.71 ± 0.81 ml of silicone oil. There was no significant difference in postoperative visual acuity scores compared with preoperative (P = 0.097), postoperative IOP(10.29 ± 0.57mmHg)was slightly higher than preoperative IOP (9.76 ± 0.48 mmHg), but there was still no statistically significant difference between the two comparisons (P = 0.405). Conclusion: Three-dimensional reconstruction prediction is a good solution for eyeballs with obvious individualized changes in severe retinal detachment, and this method helps doctors standardize FCVB size selection and the silicone oil amount for patients. [ABSTRACT FROM AUTHOR]

(1) Background: Ocular emergencies account for 1.5–3% of emergency department (ED) visits and require urgent diagnosis to prevent serious complications. Ultrasonography is a crucial, non-invasive diagnostic tool for these conditions but traditionally lacks portability and integration with modern electronic smart devices. The purpose of this study was to assess the accuracy and performance of a new handheld ultrasound device in comparison to a conventional cart-based sonographic machine in patients attending to the ED for vitreo-retinal diseases. (2) Methods: three specialists in ophthalmology, with at least 4-year experience in vitreo-retinal diseases and eye ultrasound, evaluated images of 50 eyes with both portable and traditional ultrasound probes. Each specialist made the diagnosis based on the images captured with both probes and then rated their overall image quality and confidence of diagnosis with a five-point Likert scale. The concordance of diagnosis between the two probes was evaluated. (3) Results: The sample comprised 42 patients. Twenty (40%) healthy eyes and thirty eyes with the following vitreo-retinal interface conditions were examined: 12 retinal detachment (24%), 8 vitreous hemorrhage (16%), and 10 posterior vitreous detachment (20%). The overall accuracy of the two devices appeared to be comparable (70.7% vs. 69.3%). The Butterfly iQ+ probe showed similar sensitivity in retinal detachment diagnosis (91.7% vs. 94.4% of the Accutome B-scan Pro), while it showed poor performance in diagnosing posterior vitreous detachment (sensitivity = 27.2%); (4) Conclusions: The Butterfly iQ+ device demonstrated high sensitivity in the diagnosis of retinal detachment. Significant adjustments are still needed to improve the resolution of the vitreous body. [ABSTRACT FROM AUTHOR]

Originally discovered in the nineteenth century, hyalocytes are the resident macrophage cell population in the vitreous body. Despite this, a comprehensive understanding of their precise function and immunological significance has only recently emerged. In this article, we summarize recent in-depth investigations deciphering the critical role of hyalocytes in various aspects of vitreous physiology, such as the molecular biology and functions of hyalocytes during development, adult homeostasis, and disease. Hyalocytes are involved in fetal vitreous development, hyaloid vasculature regression, surveillance and metabolism of the vitreoretinal interface, synthesis and breakdown of vitreous components, and maintenance of vitreous transparency. While sharing certain resemblances with other myeloid cell populations such as retinal microglia, hyalocytes possess a distinct molecular signature and exhibit a gene expression profile tailored to the specific needs of their host tissue. In addition to inflammatory eye diseases such as uveitis, hyalocytes play important roles in conditions characterized by anomalous posterior vitreous detachment (PVD) and vitreoschisis. These can be hypercellular tractional vitreo-retinopathies, such as macular pucker, proliferative vitreo-retinopathy (PVR), and proliferative diabetic vitreo-retinopathy (PDVR), as well as paucicellular disorders such as vitreo-macular traction syndrome and macular holes. Notably, hyalocytes assume a significant role in the early pathophysiology of these disorders by promoting cell migration and proliferation, as well as subsequent membrane contraction, and vitreoretinal traction. Thus, early intervention targeting hyalocytes could potentially mitigate disease progression and prevent the development of proliferative vitreoretinal disorders altogether, by eliminating the involvement of vitreous and hyalocytes. [ABSTRACT FROM AUTHOR]

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Aya Ikeda, Asami Shimokawa, Kazuhiro Harada, Tomoko Tsukahara-Kawamura, Jane Huang, Hiroaki Ozaki, Eiichi Uchio Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, JapanCorrespondence: Eiichi Uchio, Department of Ophthalmology, Fukuoka University School of Medicine, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan, Tel +81 92 801 1011, Fax +81 92 865 4445, Email euchio@fukuoka-u.ac.jpBackground: We have previously studied the physiological and mechanical responses of the eye to blunt trauma in various situations using finite element analysis (FEA). In this study, we evaluated the volume kinetics of an airbag impact on the eye using FEA to sequentially determine the volume change rates of intraocular segments at various airbag deployment velocities.Methods: The human eye model we created was used in simulations with the FEA program PAM-GENERISTM (Nihon ESI, Tokyo, Japan). Different airbag deployment velocities, 30, 40, 50, 60 and 70 m/s, were applied in the forward direction. The volume of the deformed eye impacted by the airbag was calculated as the integrated value of all meshes in each segment, and the decrease rate was calculated as the ratio of the decreased volume of each segment at particular timepoints to the value before the airbag impact.Results: The minimum volume of the anterior chamber was 63%, 69% and 50% at 50, 60 and 70 m/s airbag impact velocity, respectively, showing a curve with a sharp decline followed by gradual recovery. In contrast to the anterior chamber, the volume of the lens recovered promptly, reaching 80– 90% at the end of observation, except for the case of 60 m/s. Following the decrease, the volume increased to more than that of baseline at 60 m/s. The rate of volume change of the vitreous was distributed in a narrow range, 99.2– 100.4%.Conclusion: In this study, we found a large, prolonged decrease of volume in the anterior chamber, a similar large decrease followed by prompt recovery of volume in the lens, and a time-lag in the volume decrease between these tissues. These novel findings may provide an important insight into the pathophysiological mechanism of airbag ocular injuries through this further evaluation, employing a refined FEA model representing cuboidal deformation, to develop a more safe airbag system.Keywords: airbag, ocular trauma, computer simulation, lens, anterior chamber, vitreous body, finite element analysis, volume

Abstract Background The eye is a highly specialized sensory organ which encompasses the retina as a part of the central nervous system, but also non-neural compartments such as the transparent vitreous body ensuring stability of the eye globe and a clear optical axis. Hyalocytes are the tissue-resident macrophages of the vitreous body and are considered to play pivotal roles in health and diseases of the vitreoretinal interface, such as proliferative vitreoretinopathy or diabetic retinopathy. However, in contrast to other ocular macrophages, their embryonic origin as well as the extent to which these myeloid cells might be replenished by circulating monocytes remains elusive. Results In this study, we combine transgenic reporter mice, embryonic and adult fate mapping approaches as well as parabiosis experiments with multicolor immunofluorescence labeling and confocal laser-scanning microscopy to comprehensively characterize the murine hyalocyte population throughout development and in adulthood. We found that murine hyalocytes express numerous well-known myeloid cell markers, but concomitantly display a distinct immunophenotype that sets them apart from retinal microglia. Embryonic pulse labeling revealed a yolk sac-derived origin of murine hyalocytes, whose precursors seed the developing eye prenatally. Finally, postnatal labeling and parabiosis established the longevity of hyalocytes which rely on Colony Stimulating Factor 1 Receptor (CSF1R) signaling for their maintenance, independent of blood-derived monocytes. Conclusion Our study identifies hyalocytes as long-living progeny of the yolk sac hematopoiesis and highlights their role as integral members of the innate immune system of the eye. As a consequence of their longevity, immunosenescence processes may culminate in hyalocyte dysfunction, thereby contributing to the development of vitreoretinal diseases. Therefore, myeloid cell-targeted therapies that convey their effects through the modification of hyalocyte properties may represent an interesting approach to alleviate the burden imposed by diseases of the vitreoretinal interface.

A 54-year-old, one-eyed Caucasian male was admitted to the Ophthalmology Clinic due to a gradual deterioration of vision in the right eye for approximately two weeks. The patient denied any trauma or viral infection during this time. On the day of admission, the patient's best corrected visual acuity (BCVA) in the right eye was 0.5 on the Snellen scale. The patient's left eye had been atrophied for several years, with no light perception and no visibility of the fundus due to previous trauma and multiple surgeries. Ophthalmologic examination of the anterior segment and vitreous body of both eyes showed no signs of inflammation. Fundus examination of the right eye revealed scattered inflammatory foci, creamy-yellow and round, visible in all sectors. Laboratory tests, imaging studies, optical coherence tomography (OCT) angiographies, OCTs of the macula and optic nerve head, fluorescein angiographies (FAs), electroretinograms (ERGs), and visual field tests were performed. These examinations led to a diagnosis of a disease resembling birdshot-like chorioretinopathy. Immunogenetic testing of the patient did not reveal the presence of human leukocyte antigen (HLA)-A29. Dermatological and immunological consultations were conducted, and a differential diagnosis was made. Due to the reduced visual acuity (VA) observed and the inability to assess the left eye, a high-dose corticosteroid therapy was initiated, which was gradually tapered, along with the application of an immunosuppressive drug. The course of the disease was typical for birdshot chorioretinopathy, with chronic periods of remissions and exacerbations. The patient's clinical improvement was only achieved after co-administration of general corticosteroids at a dose of 0.5–1 mg/kg/day, mycofenolate mofetil, and periocular (sub-Tenon's) triamcinolone. [ABSTRACT FROM AUTHOR]

Background: Posterior globe flattening (PGF) is a specific neuroimaging sign in patients with idiopathic intracranial hypertension (IIH), but its detection is based on subjective qualitative neuroradiological assessment. This study sought to evaluate the utility of transorbital ultrasound to detect and quantify PGF in IIH patients using the Posterior Globe Angle (PGA). Methods: Consecutive IIH patients and healthy controls were enrolled in a prospective case-control study. Transorbital ultrasound was performed to assess the presence of PGF. For quantification of PGF, an angular measurement (PGA) was performed with the vertex centering the optic nerve at a predefined distance from the lamina cribrosa and angle legs tangentially aligned to the borders of the vitreous body. PGA measurements were compared between IIH patients and healthy controls. Additionally, the diagnostic accuracy of PGA measurements in detecting PGF was evaluated using ROC analysis. Results: Thirty-one IIH patients (37.3 ± 12.3 years, 29 female) and 28 controls (33.3 ± 11.8 years, 21 female) were compared. PGF was present in 39% of IIH patients and absent in the control group. PGA3mm measurements significantly differed between IIH and controls (116.5° ± 5.5 vs. 111.7° ± 2.9; p < 0.001). A PGA3mm cutoff of ≥ 118.5° distinguished IIH patients from controls with 100% specificity, while retaining a sensitivity of 37.5%. Conclusions: Transorbital ultrasound may be applied to detect and quantify PGF in IIH patients. Prospective, multicenter studies with extended cohorts and blinded design are needed to validate these preliminary findings and confirm the diagnostic utility of transorbital ultrasound for the assessment of PGF in IIH. [ABSTRACT FROM AUTHOR]

This document is a response to a letter to the editor regarding a study on calculating individual vitreous volume for tailored patient dosing in intravitreal therapy. The authors of the study appreciate the positive response from the letter's authors and acknowledge the importance of considering the lens status (phakic or pseudophakic) in the calculation of vitreous volume. They discuss the limitations of their study and present a clinical case that shows the minor relevance of lens status in the calculation. The authors recommend their formula for predicting vitreous volume and suggest further studies to analyze the advantages and disadvantages of a customized approach in intravitreal therapy. [Extracted from the article]

Anti-VEGF agents, e.g., bevacizumab, are used in retinal surgery, while their interaction with silicone oils and novel hydrogels remains unclear. This study examines the in vitro pharmacokinetics of bevacizumab in silicone oil-filled eyes compared to various hydrogel replacements and the porcine vitreous body as well as its impact on the interface tension of silicone oils. An in vitro model filled with light or heavy silicone oil, porcine vitreous bodies, or hydrogels (alginate and polyethylene glycol (PEG)-based) was equilibrated with a balanced salt solution. Monitoring of bevacizumab in the aqueous phase was conducted for up to 24 h, and its effect on interfacial tension was studied. Significant differences in bevacizumab partitioning were observed across endotamponades after 24 h. In silicone oils, bevacizumab was found exclusively in the aqueous phase, while in the other endotamponades, it accumulated in the gel phase (96.1% in porcine vitreous body, 83.5% in alginate, and 27.6% in PEG-based hydrogel). Bevacizumab significantly reduced interfacial tension (40 to 8 mN/m), possibly enhancing silicone oil emulsification. The type of endotamponade heavily influenced the bevacizumab concentration in the aqueous. The vitreous body and replacement hydrogels likely serve as a drug reservoir, highlighting the need for in vivo studies to explore these interactions prior to clinical application. [ABSTRACT FROM AUTHOR]

Melting is an efficient method to turn municipal solid waste incineration (MSWI) fly ash (FA) into non-hazardous material. Coal fly ash (CFA) was selected as the silica-alumina source to carry out co-melting research with MSWI FA in this work. The effects of the temperature and the CFA content on mineral transformation and the migration characteristics of heavy metals were analyzed. The results showed that the mixtures of MSWI FA and CFA reacted at high temperatures to mainly generate Ca2Al2SiO7, Ca2SiO4, and CaAl2Si2O8 primarily and then melted and formed the amorphous-phase vitreous body when the CFA content was more than 40% and the temperature was higher than 1300 °C. During the melting process, Cd and Pb were almost volatilized, while Cr, Mn, and Ni were almost retained. Besides, the volatilization rates of Cu and Zn fluctuated with the temperature and the CFA content. Suitable treatment temperature and CFA content were conducive to the transformation of the heavy metals in the FA into stable forms, and the melting products were no longer hazardous wastes because the vitreous body could effectively encapsulate heavy metals. This study aims to help reuse the FA and CFA collaboratively and be more environmentally friendly. [ABSTRACT FROM AUTHOR]

Background: The eye is a highly specialized sensory organ which encompasses the retina as a part of the central nervous system, but also non-neural compartments such as the transparent vitreous body ensuring stability of the eye globe and a clear optical axis. Hyalocytes are the tissue-resident macrophages of the vitreous body and are considered to play pivotal roles in health and diseases of the vitreoretinal interface, such as proliferative vitreoretinopathy or diabetic retinopathy. However, in contrast to other ocular macrophages, their embryonic origin as well as the extent to which these myeloid cells might be replenished by circulating monocytes remains elusive. Results: In this study, we combine transgenic reporter mice, embryonic and adult fate mapping approaches as well as parabiosis experiments with multicolor immunofluorescence labeling and confocal laser-scanning microscopy to comprehensively characterize the murine hyalocyte population throughout development and in adulthood. We found that murine hyalocytes express numerous well-known myeloid cell markers, but concomitantly display a distinct immunophenotype that sets them apart from retinal microglia. Embryonic pulse labeling revealed a yolk sac-derived origin of murine hyalocytes, whose precursors seed the developing eye prenatally. Finally, postnatal labeling and parabiosis established the longevity of hyalocytes which rely on Colony Stimulating Factor 1 Receptor (CSF1R) signaling for their maintenance, independent of blood-derived monocytes. Conclusion: Our study identifies hyalocytes as long-living progeny of the yolk sac hematopoiesis and highlights their role as integral members of the innate immune system of the eye. As a consequence of their longevity, immunosenescence processes may culminate in hyalocyte dysfunction, thereby contributing to the development of vitreoretinal diseases. Therefore, myeloid cell-targeted therapies that convey their effects through the modification of hyalocyte properties may represent an interesting approach to alleviate the burden imposed by diseases of the vitreoretinal interface. [ABSTRACT FROM AUTHOR]

Purpose – to evaluate the demographic and clinical characteristics and treatment efficiency of patients by vitrectomy due to retinal detachment against the background of combined eye pathologies. The observation was conducted in the Clinic of Educational Surgery of the Azerbaijan State Medical Institute named after A. Aliyev. The case histories of 500 patients diagnosed with retinal detachment against the background of combined eye pathologies were studied by random sampling, 197 of whom underwent vitrectomy. Data on the demographic and clinical characteristics of these patients were collected. Before the operation, visual acuity and intraocular pressure were assessed. Information on registered complications after the operation, the results of optical coherence tomography on day 10 after treatment, as well as visual acuity indicators were provided for in the observation program and obtained in a standard manner for all patients. The obtained results were processed statistically using the "data analysis" package of the Excel program. The collected data were grouped by variants of features, the specific weight of each group and subgroup in the aggregate was calculated. The obtained data showed that in 197 (34.9±2.2%) patients with retinal detachment against the background of combined pathologies who underwent vitrectomy, the gender difference was not significant. The overwhelming majority of patients were admitted for treatment with a great delay. Basically, combined pathologies of the cornea (16.2%), lens (45.2%) and vitreous body (5.3%) prevailed. Combined eye pathologies in patients with retinal detachment during vitrectomy are often complicated by choroidal rupture (4.1%), increased intraocular pressure (7.6%), diplopia (3.6%), hemophthalmos (2.5%) and cataract (22.8%). The main etiologic factors of retinal detachment against the background of combined eye pathologies are myopia (50.3%), eye injuries (30.9%). [ABSTRACT FROM AUTHOR]

Background: Activated microglia release harmful substances to retinal ganglion cells (RGCs), but may also benefit by removing cellular debris and secreting neurotrophic factors. These paradoxical roles remain controversial because the nature and time-course of the injury that defines their role is unknown. The aim of this study was to determine if pharmacological manipulation of microglia to acquire a pro-inflammatory or pro-survival phenotype will exacerbate or enhance neuronal survival after injury.Material and methods: Treated HAP I (highly aggressively proliferating immortalized) microglia were injected into the vitreous or tail vein (T V) of female Sprague-Dawley rats. Retinas were examined at 4-14 days following optic nerve crush (ONC) and the number of surviving RGCs was determined.Results: Injection of untreated HAP I cells resulted in the greater loss of RGCs early after ONC when injected into the vitreous and later after ONC when injected into the T V. LP S activated HAP I cells injected into the vitreous resulted in greater RGC loss with and without injury. When injected into the T V with ONC there was no loss of RGCs 4 days after ONC but greater loss afterwards. Minocycline treated HAP I cells injected into the vitreous resulted in greater RGC survival than untreated HAP I cells. However, when injected into the T V with ONC there was greater loss of RGCs. These results suggest that optic nerve signals attract extrinsic microglia to the retina, resulting in a proinflammatory response.Conclusion: Neuroprotection or cytotoxicity of microglia depends on the type of activation, time course of the injury, and if they act on the axon or cell body. HAPI microglia migrate to the retina or optic nerve following optic nerve injury when injected into the vitreous or tail vein, respectively. Pretreatment with LPS or minocycline differentially effects retinal ganglion cell survival. In most cases, the result late in the injury process is greater retinal ganglion cell loss. We show here that neuroprotection is not solely determined by the microglial activation state but factors such as the environment and time-course of the injury. Culture microglia can be treated in vitro and then injected in vivo. The cells migrate to the site of injury, cell body of retinal ganglion cells if in the vitreous or to the optic nerve if injected in the tail vein. Retinal ganglion cell death is dependent on the location the microglia act, time-course of injury, and activation state. Proinflammatory microglia can be neuroprotective early in the injury when the primary site of action is on the axons whereas hypoactivated microglia are neuroprotective early in injury when they act on the soma. Later in the injury, both become detrimental. [ABSTRACT FROM AUTHOR]

Introduction: The purpose of our study was to compare the safety and efficacy of two scleral fixation intraocular lens (IOL) methods of four-point scleral fixation (Akreos AO60) and the Yamane technique (AcrySof MA60AC). Methods: This prospective, randomized study was conducted at the Military Institute of Medicine—National Research Institute in Warsaw between 2021 and 2023. We compared both groups for cause of aphakia, ocular history, refractive status, and complication. Results: Our study included 50 eyes from 47 patients. Four-point fixation was performed in 25 eyes (group 1), and the Yamane technique was used in 25 eyes (group 2). Surgical time was 24.1 min ± 8.9 in group 1 and 25.1 min ± 9.9 in group 2 (p > 0.05). The postoperative BCVA (best-corrected visual acuity) for group 1 and group 2 at 1 year's observation was 0.10 ± 0.15 and 0.09 ± 0.17 logMAR, respectively (p > 0.05). Postoperative total refractive error (RE) was − 0.06 ± 0.71 diopters (D) for four-point scleral fixation and 0.83 ± 0.70 D for Yamane technique (p < 0.05). Endothelial cell density (ECD) loss was 0.9% in group 1 and 3.5% in group 2 (p > 0.05). Bleeding into the anterior chamber and vitreous body was more frequent in the group of patients operated on with the use of the Yamane technique (10 cases, 20%, p = 0.01). IOL displacement was found in one case (2%) in group 2. Conclusions: Both analyzed techniques are well tolerated and ensure good refractive results (extremely predictable in four-point scleral fixation) and have a similar safety profile. Four-point scleral fixation of IOL would appear to be safe, effective and beneficial for young, active patients, especially after trauma or recurrent subluxation. Clinical Trial Registration: ClinicalTrials.gov identifier NCT06389643. [ABSTRACT FROM AUTHOR]

Purpose: Wet age-related macular degeneration (AMD) is a blinding retinal disease. Monthly intravitreal anti-VEGF antibody injections of bevacizumab (off-label) and ranibizumab (FDA approved) are the standard of care. Antibody aggregation may interfere with ocular absorption/distribution. This study assessed topical delivery of dilute antibodies to the posterior segment of rabbit eyes using a novel anti-aggregation formula (AAF). Methods: Bevacizumab, or biosimilar ranibizumab was diluted to 5 mg/ml in AAF. All rabbits were dosed twice daily. Substudy 1 rabbits (bevacizumab, 100 µl eye drops): Group 1 (bevacizumab/AAF, n = 6); Group 2 (bevacizumab/PBS, n = 7) and Vehicle control (AAF, n = 1). Substudy 2 rabbits (ranibizumab biosimilar/AAF, 50 µl eye drops): (ranibizumab biosimilar/AAF, n = 8). At 14.5 days, serum was drawn from rabbits. Aqueous, vitreous and retina samples were recovered from eyes and placed into AAF aliquots. Tissue analyzed using AAF as diluent. Results: Bevacizumab in AAF permeated/accumulated in rabbit aqueous, vitreous and retina 10 times more, than when diluted in PBS. AAF/0.1% hyaluronic acid eye drops, dosed twice daily, provided mean tissue concentrations (ng/g) in retina (29.50), aqueous (12.34), vitreous (3.46), and serum (0.28 ng/ml). Additionally, the highest concentration (ng/g) of ranibizumab biosimilar was present in the retina (18.0), followed by aqueous (7.82) and vitreous (1.47). Serum concentration was negligible (< 0.04 ng/ml). No irritation was observed throughout the studies. Conclusions: Bevacizumab and ranibizumab, in an AAF diluent eye drop, can be delivered to the retina, by the twice daily dosing of a low concentration mAb formulation. This may prove to be an adjunct to intravitreal injections. [ABSTRACT FROM AUTHOR]

Objective: To determine the role of real time ultrasound B-scan in postoperative prognosis among patients with advanced cataract by documenting preoperative frequency of different posterior segment pathologies. Study Design: Cross-sectional study. Place and Duration of Study: Radiology Department, Pak Emirates Military Hospital, Rawalpindi Pakistan, from Jan to Oct 2011. Methodology: The study utilized ultrasound eye, carried on the patients with closed eyes in supine position with ultrasound transmission gel applied to prevent transducer touching eyelid. Scan was performed in both sagital and transverse plane. Results: A total of 336 patients were included in this study, with mean age of 56.92±12.89 years, 162(48.21%) male rest female. Cataracts were found in 144 (42.86%) left eyes and 154 (45.83%) right eyes. Mature cataract was seen in 292 (86.9%) patients, while 32(9.52%) had traumatic and 304(90.47%) had non-traumatic cataract. In non-traumatic cataract, retinal detachment (RD) was in 14(4.6%) patients, vitreous detachment (VD) in 13(4.3%) and vitreous detachment/hemorrhage in 21(6.9%) patients. Optic disc cupping was seen in 6(2.0%) non-traumatic cases and other pathologies were seen in 7(2.3%) patients having nontraumatic and 3(9.38%) patients having traumatic cataract. Conclusion: Preoperative posterior segment evaluation with ultrasound in patients with dense cataract can be used to detect pathologies that may influence the surgical strategy and postoperative visual prognosis. [ABSTRACT FROM AUTHOR]

Background: To investigate association between optic disc parameters analyzed by optical coherence tomography (OCT) and occurrence of peripheral retinal tears in patients with symptomatic posterior vitreous detachment (PVD). Methods: This cross-sectional study enrolled 75 patients with symptoms of acute PVD, who were allocated into two groups based on whether a peripheral retinal tear occurred or not. Results: When comparing the average retinal nerve fiber layer (RNFL) thickness (μm) between retinal tear and control groups, it was shown that patients with a retinal tear have a significantly higher (87.18 [95% confidence interval (CI), 84.47 to 89.9] vs 81.14 [95% CI, 77.81 to 84.46], P = 0.005) average RNFL thickness. Furthermore, we observed a significant difference (0.13, 0.06 to 0.22 vs 0.07, 0.04 to 0.1, P = 0.036, Mann–Whitney U-test) in the size of cup volume (mm3) between the tear and control groups, respectively. Linear regression showed a significant decrease (P = 0.029) in average RNFL thickness with increasing age, but without a significant difference between the two groups. There was no statistically significant difference between the tear and control groups in terms of rim area, disc area, and average cup-to-disc ratio. Conclusion: Patients with a higher average RNFL thickness and larger cup volume measured by OCT were more prone to develop a peripheral retinal tear. Increased peripapillary average RNFL thickness due to trauma and subsequent inflammation, possibly related to the more adherent posterior hyaloid membrane to the retina, may also indicate strengthened adhesions in the areas of the peripheral retina where retinal tears occur. OCT analysis of the optic nerve head may be used in everyday clinical practice as a predictor of the development of peripheral retinal tears in patients with symptomatic PVD. [ABSTRACT FROM AUTHOR]

Retinoblastoma, a rare cancer mostly affecting children, makes up ~3% of childhood cancers in developed countries. However, it is more prevalent in sub-Saharan Africa, where late diagnosis often leads to advanced disease and higher mortality rates. Here, we present a 3-year-old girl presented with leukocoria and esotropia in her left eye for 3 months. Imaging revealed lens calcification and vitreous seeding, classified as group D, stage I. The child underwent enucleation to save her life, and histopathology showed Flexner–Wintersteiner rosette cells. This case underscores the importance of eye exams at birth and during childhood. Primary healthcare providers should recognize symptoms like leukocoria and esotropia to facilitate early diagnosis of retinoblastoma. [ABSTRACT FROM AUTHOR]

Tomohiro Ueno, Hideaki Fujita, Aya Ikeda, Kazuhiro Harada, Tomoko Tsukahara-Kawamura, Hiroaki Ozaki, Eiichi Uchio Department of Ophthalmology, Fukuoka University School of Medicine, Fukuoka, JapanCorrespondence: Eiichi Uchio, Department of Ophthalmology, Fukuoka University School of Medicine, 7-45-1 Nanakuma, Jonan-ku, Fukuoka, 814-0180, Japan, Tel +81 92 801 1011, Fax +81 92 865 4445, Email euchio@fukuoka-u.ac.jpBackground: We studied the kinetic phenomenon of an airbag impact on eyes with different axial lengths using finite element analysis (FEA) to sequentially determine the physical and mechanical responses of intraocular segments at various airbag deployment velocities.Methods: The human eye model we created was used in simulations with the FEA program PAM-GENERISTM. The airbag was set to impact eyes with axial lengths of 21.85 mm (hyperopia), 23.85 mm (emmetropia) and 25.85 mm (myopia), at initial velocities of 20, 30, 40, 50 and 60 m/s. The deformation rate was calculated as the ratio of the length of three segments, anterior chamber, lens and vitreous, to that at the baseline from 0.2 ms to 2.0 ms after the airbag impact.Results: Deformation rate of the anterior chamber was greater than that of other segments, especially in the early phase, 0.2– 0.4 ms after the impact (P < 0.001), and it reached its peak, 80%, at 0.8 ms. A higher deformation rate in the anterior chamber was found in hyperopia compared with other axial length eyes in the first half period, 0.2– 0.8 ms, followed by the rate in emmetropia (P < 0.001). The lens deformation rate was low, its peak ranging from 40% to 75%, and exceeded that of the anterior chamber at 1.4 ms and 1.6 ms after the impact (P < 0.01). The vitreous deformation rate was lower throughout the simulation period than that of the other segments and ranged from a negative value (elongation) in the later phase.Conclusion: Airbag impact on the eyeball causes evident deformation, especially in the anterior chamber. The results obtained in this study, such as the time lag of the peak deformation between the anterior chamber and lens, suggest a clue to the pathophysiological mechanism of airbag ocular injury.Keywords: airbag, ocular trauma, computer simulation, lens, anterior chamber, vitreous body, finite element analysis, deformation

AIM: To explore the relationship of miR-126 and miR-325 in serum and vitreous with the severity of proliferative vitreoretinopathy(PVR).METHODS: A total of 100 cases(100 eyes)with PVR who were treated in our hospital from October 2019 to October 2022 were selected and retrospectively studied. They were divided into a mild group(42 eyes)and a severe group(58 eyes)according to the degree of retinopathy, and another 30 cases(30 eyes)that underwent vitrectomy without retinopathy due to eye trauma in our hospital during the same period were selected as the control group. Fluorescence quantitative PCR was used to detect the expression levels of miR-126 and miR-325 in serum and vitreous; ELISA was used to detect the levels of transforming growth factor β(TGF-β), platelet-derived growth factor(PDGF), vascular endothelial growth factor(VEGF), and tumor necrosis factor α(TNF-α)in serum and vitreous; and Pearson's method was used to analyze the correlation between the serum and vitreous levels of miR-126 and miR-325 correlated with the levels of TGF-β, PDGF, VEGF, and TNF-α; Logistic multifactorial analysis was used to analyze the influencing factors for the occurrence of severe PVR.RESULTS: Compared with the control group, miR-126 levels in serum and vitreous of PVR patients were decreased and lower in the severe PVR group than in the mild PVR group(both P

Background: The main purpose of this paper is to introduce a method that can accurately locate the posterior capsule of the lens to facilitate a relatively complete resection of the anterior vitreous body. Methods: A total of 51 patients in the experimental group and control group were enrolled in this study. Phacoemulsification combined with vitrectomy was performed in all cases. After the cataract procedure was completed in the control group, the surgeon performed a conventional anterior vitrectomy with the operative eye. In the experimental group, anterior vitrectomy was performed according to the threadiness corrugation of the posterior capsule of the lens. During the operation, with the help of triamcinolone, two surgeons confirmed the resection of the anterior vitreous cortex; the best corrected visual acuity and intraocular pressure of all patients were recorded at 1 week, 1 month and 3 months after surgery. Results: Fifty patients underwent phacoemulsification combined with vitrectomy, except one patient in the experimental group who was lost to follow-up. After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. There was no significant difference in preoperative visual acuity between the two groups (t = 0.83, P = 0.25). Both groups had varying degrees of improvement in best corrected visual acuity at 1 week, 1 month and 3 months after surgery. Moreover, there was no significant difference in BCVA between the two groups at the three follow-up time points (t=-1.15, -1.65, -1.09, P = 0.53, 0.21, 0.23). After surgery, no significant complications were observed in all patients except two patients in the control group with temporary increases in intraocular pressure. Incomplete resection of the anterior vitreous cortex was observed in 2 patients in each group, but there was no significant difference (χ2 = 7.81, P > 0.05). Conclusion: In the process of cataract surgery combined with vitrectomy, thready corrugation appears in the posterior capsule of the lens and is an important sign of its localization. Anterior vitrectomy can be accomplished safely and effectively with the help of thread-like corrugation, and the surgical effect is almost the same as that of traditional surgery. Especially suitable for beginners in vitreous surgery. [ABSTRACT FROM AUTHOR]

Background: This study aims to investigate the factors affecting the vitreous levels of pigment epithelium-derived factor (PEDF) and vascular endothelial growth factor (VGEF) among patients with pars plana vitrectomy (PPV). Also, this study correlates the levels of PEDF with RRD characteristics. Methods: All patients who were scheduled for PPV for any indication were included in the study. They were divided into a case group which included patients with advanced PDR and a control group which included the remaining diagnoses. During the PPV, an undiluted vitreous sample was taken and the enzyme-linked immunosorbent assay method was utilized to measure the levels of VEGF and PEDF. Results: Eighty eyes were involved. Patients diagnosed with advanced PDR and endophthalmitis exhibited higher levels of VEGF. PEDF was affected inversely by the age of the patients and PEDF levels were higher in RRD and endophthalmitis cases. In patients with RRD, the level of PEDF was higher if the tear was found inferiorly, if the macula was detached, and with a longer duration of RRD. Conclusions: This study highlights the clinical importance of those biomarkers. Anti-VEGF-based treatment is the mainstay against PDR. PEDF may show a promising predictive values regarding patients with RRD. [ABSTRACT FROM AUTHOR]

The annual increase in myopia prevalence poses a significant economic and health challenge. Our study investigated the effect of calcitriol role in myopia by inducing the condition in guinea pigs through form deprivation for four weeks. Untargeted metabolomics methods were used to analyze the differences in metabolites in the vitreous body, and the expression of vitamin D receptor (VDR) in the retina was detected. Following form deprivation, the guinea pigs received intraperitoneal injections of calcitriol at different concentrations. We assessed myopia progression using diopter measurements and biometric analysis after four weeks. Results indicated that form deprivation led to a pronounced shift towards myopia, characterized by reduced choroidal and scleral thickness, disorganized collagen fibers, and decreased scleral collagen fiber diameter. Notably, a reduction in calcitriol expression in vitreous body, diminished vitamin D and calcitriol levels in the blood, and decreased VDR protein expression in retinal tissues were observed in myopic guinea pigs. Calcitriol administration effectively slowed myopia progression, preserved choroidal and scleral thickness, and prevented the reduction of scleral collagen fiber diameter. Our findings highlight a significant decrease in calcitriol and VDR expressions in myopic guinea pigs and demonstrate that exogenous calcitriol supplementation can halt myopia development, enhancing choroidal and scleral thickness and scleral collagen fiber diameter. [ABSTRACT FROM AUTHOR]

Purpose: The main purpose of this study was to perform an immunohistochemical, functional, and anatomical evaluation of patients with idiopathic epiretinal membrane (ERM). Methods: Twenty-four specimens of idiopathic ERM from 24 consecutive patients who underwent 23 G pars plana vitrectomy for ERM and internal limiting membrane (ILM) peeling at the San Juan University Hospital in Alicante (Spain) in 2019 were analyzed. All patients underwent a complete ophthalmological examination including measurement of best corrected visual acuity (BCVA) and macular analysis by spectral-domain optical coherence tomography (SD-OCT) at the time of diagnosis and 3 months after surgery. Specific glial fibrillar acid protein antibodies (GFAP) and S100 calcium-binding protein β (S100β) immunostaining markers were used to identify the macroglial component of the ERM, Müller cells, and astrocytes. Ionized calcium-binding adapter molecule 1 protein (Iba1) antibodies were used as specific markers for inflammatory cells, such as microglia and macrophages. Results: Mean preoperative BCVA measured with Snellen chart was 0.3 and 0.6 preoperatively and at 3 months after surgery, respectively. SD-OCT identified 15 patients (62.5%) with a disruption of the outer retinal hyperreflective bands. The immunohistochemical study showed the presence of Müller cells in almost all cases (91.6%), as well of abundant microglia and macrophages. Microglia and macrophages were more frequently present in earlier stages of ERM. Microglia were present in ERM independently of the outer retinal hyperreflective bands integrity as measured by SD-OCT. A greater presence of macrophages was found in those ERMs with no outer retinal hyperreflective band disruption. Conclusions: Müller cells seem to be the most frequent cell group in ERMs, with also presence of microglia cells and macrophages. Astrocytes were more frequently found in early stages of ERMs. Microglia and macrophages were most frequent in ERMs with early stage (1, 2, or 3) than in advanced stages (4). [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Primary vitreoretinal lymphoma (PVRL) is a rare subtype of DLBCL and can progress into primary central nervous system lymphoma (PCNSL). To investigate the role of chronic antigenic stimulation in PVRL, we cloned and expressed B-cell receptors (BCR) from PVRL patients and tested for binding against human auto-antigens. SEL1L3, a protein with multiple glycosylation sites, was identified as the BCR target in 3/20 PVRL cases. SEL1L3 induces proliferation and BCR pathway activation in aggressive lymphoma cell lines. Moreover, SEL1L3 conjugated to a toxin killed exclusively lymphoma cells with respective BCR-reactivity. Western Blot analysis indicates the occurrence of hyper-N-glycosylation of SEL1L3 at aa 527 in PVRL patients with SEL1L3-reactive BCRs. The BCR of a PVRL patient with serum antibodies against SEL1L3 was cloned from a vitreous body biopsy at diagnosis and of a systemic manifestation at relapse. VH4-04*07 was used in both lymphoma manifestations with highly conserved CDR3 regions. Both BCRs showed binding to SEL1L3, suggesting continued dependence of lymphoma cells on antigen stimulation. These results indicate an important role of antigenic stimulation by post-translationally modified auto-antigens in the genesis of PVRL. They also provide the basis for a new treatment approach targeting unique lymphoma BCRs with ultimate specificity. [ABSTRACT FROM AUTHOR]

Background: Endotamponade of the vitreous body with silicone oil is a common procedure, being the basis of many vitreoretinal surgeries. However, emulsification may happen, which is a clinically relevant adverse event of silicone oil use. Methods: This review provides a thorough analysis of the emulsification process. It focuses on describing factors affecting this event as well as its possible subsequent complications. Results: The viscosity of silicone oil, the duration of emulsification, the status of the lens and many other factors have an influence on the onset and intensity of emulsification. This phenomenon carries several risks for operated eyes such as increased intraocular pressure, keratopathy or structural changes to the retina. Conclusions: The use of modern imaging techniques, especially optical coherence tomography, enables faster detection of the emulsification process. This allows for an adequate clinical response and more accurate follow-up of the patient. [ABSTRACT FROM AUTHOR]

Simple Summary: Uveitis in horses is the most common ocular disease and causes blindness and cataracts in horses. The aim of this study was to evaluate vision and complications after phacoemulsification (emulsification and aspiration of the lens cortex/nucleus from the eye) combined with pars plana vitrectomy (removal of vitreous body from the vitreous chamber) in horses with uveitis-associated cataracts. Additionally, the surgical technique with and without posterior capsulorhexis (removal of the posterior lens capsule) during phacoemulsification (PE) was compared. Uveitis-associated cataracts were treated with phacoemulsification combined with pars plana vitrectomy under identical conditions in 12 eyes of 10 horses with posterior capsulorhexis and 20 eyes of 18 horses without posterior capsulorhexis. Horses underwent pre-, postoperative, and follow-up examinations. In the period 12–18 months postoperatively, 3/7 (42.9%) eyes treated without posterior capsulorhexis, and 2/9 (22.2%) eyes treated with posterior capsulorhexis were visual. In the period > 24 months postoperatively, 2/7 (28.6%) eyes treated without posterior capsulorhexis and 1/8 (12.5%) eyes treated with posterior capsulorhexis were visual. In the overall population, a significant decrease in the number of eyes with postoperative active uveitis was observed during follow-up examinations (p < 0.001). A significant increase in the number of eyes that were blind due to retinal detachment was observed in the overall patient population as the examination period progressed (p < 0.001). Retinal detachment was the sole long-term cause of blindness. In horses diagnosed with uveitis-associated cataracts, no persistent active uveitis was observed following the described treatment during the follow-up examinations. However, the proportion of eyes that were blind due to retinal detachment increased. Thus, while the surgery may prevent postsurgical persistent active uveitis and remove lens opacity, the prognosis for a visual outcome is guarded. A superior outcome in postsurgical vision was observed in eyes treated without posterior capsulorhexis. Background: Cataracts resulting from equine recurrent uveitis (ERU) or other forms of uveitis are usually associated with rapid progression. ERU is the most common ocular disease cause of blindness and cause of cataracts in horses. The necessity for the posterior capsulorhexis (PC) during phacoemulsification (PE) is controversial. This study aimed to evaluate vision and complications after PE combined with pars plana vitrectomy (PPV) in horses with uveitis-associated cataracts and compare the PE technique with and without posterior capsulorhexis. Methods: Thirty-two eyes of 28 horses with uveitis-associated cataracts aged 14 months to 19.6 years were treated with PE-PPV under identical conditions. Twenty-three eyes of 21 horses were affected by an ERU-associated (ERU group), and nine eyes of 7 horses were affected by cataracts related to uveitis with pathogenesis different to ERU (non-ERU group). PE-PPV was performed in 12 eyes of 10 horses (PC group) and 20 eyes of 18 horses without posterior capsulorhexis (NPC group). Follow-up examination was performed at a mean of 1.7 ± 1.8 years postoperatively (range: 1 month–6.4 years). Results: In the period up to 1 month postoperatively, 17/20 (85%) NPC-eyes and 8/12 (67%) PC-eyes (total: 25/32 [78%]) were visual. From 1–6 months postoperatively, 16/20 (80%) NPC-eyes and 7/12 (58.3%) PC-eyes (total: 23/32 [72%]), and from 6–12 months, 7/11 (63.6%) NPC-eyes and 3/8 (37.5%) PC-eyes (total: 10/19 [52.6%]) were visual. From 12–18 months postoperatively, 3/7 (42.9%) NPC-eyes and 2/9 (22.2%) PC-eyes (total: 5/16 [31.3%]), and from 18–24 months, 3/8 (37.5%) NPC-eyes and 1/8 (12.5%) PC-eyes (total: 4/16 [25%]) were visual. After 24 months postoperatively, 2/7 (28.6%) NPC-eyes and 1/8 (12.5%) PC-eyes (total: 3/15 [20%]) were visual. Despite the higher number of visual eyes in the NPC group at each time point, differences were not significant. No obvious differences regarding postsurgical vision were observed between the ERU- and non-ERU groups at each time point. In the overall population, a significant decrease in the number of eyes with postoperative active uveitis was observed during the follow-up examinations (p < 0.001). A significant increase in the number of eyes that were blind due to retinal detachment was observed in the overall patient population as the examination period progressed (p < 0.001). Retinal detachment was the sole long-term cause of blindness. Conclusions: In horses diagnosed with uveitis-associated cataracts and treated with PE-PPV, no persistent active uveitis was observed in the present study during follow-up examinations. However, the proportion of eyes that were blind due to retinal detachment increased. Whilst PE-PPV may prevent postsurgical persistent active uveitis and remove lens opacity, the prognosis for a visual outcome is guarded. A superior outcome in postsurgical vision was observed in the NPC group. However, caution is required when interpreting these results due to several factors that affect the independent comparison of the surgical groups. [ABSTRACT FROM AUTHOR]

Introduction: The classically defined two retinal microglia layers are distributed in inner and outer plexiform layers. Although there are some reports that retinal microglia are also superficially located around the ganglion cell layer (GCL) in contact with the vitreous, there has been a lack of detailed descriptions and not fully understood yet. Methods: We visualized the microglial layers by using CX3CR1-GFP (C57BL6) transgenic mice with both healthy and disease conditions including NaIO3- induced retinal degeneration models and IRBP-induced auto-immune uveitis models. Result: We found the GCL microglia has two subsets; peripheral (pph) microglia located on the retinal parenchyma and BAM (CNS Border Associated Macrophage) which have a special stretched phenotype only located on the surface of large retinal veins. First, in the pph microglia subset, but not in BAM, Galectin-3 and LYVE1 are focally expressed. However, LYVE1 is specifically expressed in the amoeboid or transition forms, except the typical dendritic morphology in the pph microglia. Second, BAM is tightly attached to the surface of the retinal veins and has similar morphology patterns in both the healthy and disease conditions. CD86+ BAM has a longer process which vertically passes the proximal retinal veins. Our data helps decipher the basic anatomy and pathophysiology of the retinal microglia in the GCL. Discussion: Our data helps decipher the basic anatomy and pathophysiology of the retinal microglia in the GCL. [ABSTRACT FROM AUTHOR]

This article provides a review of pediatric traumatic macular holes (TMHs), which are full-thickness defects in the foveal center of the retina caused by sudden ocular trauma. TMHs are rare and most common in young males who engage in a more active lifestyle. Unlike idiopathic macular holes (IMHs), TMHs have a higher chance of spontaneous closure. The management of TMHs in the pediatric population is not well-established, but observation, topical anti-inflammatories, and surgical closure with vitrectomy are common treatment options. The article also discusses the pathophysiology of TMHs and factors that may contribute to their closure. [Extracted from the article]

Purpose: Removing transparent vitreous tissues, such as a residual vitreous cortex (VC) or proliferative membrane, without damaging the retina is often problematic in vitrectomy. We examined the feasibility of an injectable in situ cross-linking hyaluronan hydrogel (XL-HA) for vitrectomy. Study design: Experiments using ex vivo and in vivo animal models. Methods: HA-dibenzocyclooctyne and HA-azidoethylamine solutions were mixed to form XL-HA, which then gradually formed a hydrogel. We tested the function of XL-HA in ex vivo porcine eyes. We then examined the performance of XL-HA in in vivo rabbit models of posterior vitreous detachment, posterior VC removal, and proliferative vitreoretinopathy. Results: The ex vivo study showed that XL-HA rapidly embedded triamcinolone acetonide, mimicking VC attached to the retina, and became hard enough to be pinched with tweezers within 3 minutes, allowing us to remove only the triamcinolone acetonide without impairing the internal limiting membrane. In the in vivo rabbit models, XL-HA injection improved posterior vitreous detachment, and the thin and fragile posterior VC or fibrous proliferative membrane was readily peeled off without any damage to the underlying retina as compared with untreated controls. A short-term intraocular biocompatibility test demonstrated that the intraocular pressure remained normal with XL-HA injected into the eye. In addition, transmission electron microscopy showed no obvious abnormalities in the cornea or in the inner and outer retina. Conclusion: The results indicate that XL-HA is a potential adjunctive device to help make vitrectomy safe, effective, and successful. [ABSTRACT FROM AUTHOR]

We conducted a study on the impact of intraperitoneal injections of melatonin and its three bioisosteres (compounds 1–3) on the development of oxygen‐induced retinopathy in newborn rats during a 21‐day experiment. It was demonstrated that melatonin and its analogues 1–3 effectively reduce the total protein concentration in the vitreous body of rat pups, decrease concentration of VEGF‐A, and lower the level of oxidative stress (as indicated by normalization of antioxidant activity in the vitreous body). Melatonin and its analogues 1–3 equally normalize the level of VEGF‐A. Analogues 1 and 2 even exceed melatonin in their ability to reduce protein influx into the vitreous body. However, analogue 2 had no effect on antioxidant activity, while analogues 1 and 3 caused a significant increase in this parameter, with analogue 3 even slightly exceeding melatonin. Thus, it can be concluded that analogues 1–3 are comparable to melatonin and can be utilized as potential therapeutic agents for the treatment of retinopathy of prematurity. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases affecting the visual system encompass glaucoma, macular degeneration, retinopathies, and inherited genetic disorders such as retinitis pigmentosa. These ocular pathologies pose a serious burden of visual impairment and blindness worldwide. Current treatment modalities include small molecule drugs, biologics, or gene therapies, most of which are administered topically as eye drops or as injectables. However, the topical route of administration faces challenges in effectively reaching the posterior segment and achieving desired concentrations at the target site, while injections and implants risk severe complications, such as retinal detachment and endophthalmitis. This necessitates the development of innovative therapeutic strategies that can prolong drug release, deliver effective concentrations to the back of the eye with minimal systemic exposure, and improve patient compliance and safety. In this review, we introduce retinal degenerative diseases, followed by a discussion of the existing clinical standard of care. We then delve into detail about drug and gene delivery systems currently in preclinical and clinical development, including formulation and delivery advantages/drawbacks, with a special emphasis on potential for clinical translation. [Display omitted] • Retinal degeneration arises from various conditions ranging from inherited disorders to complications of preexisting disease • Drug delivery to the eye is faced by many barriers including the tear film, cornea, and blood retina barrier • Direct injections to specific eye compartments such as the subretinal or vitreous space facilitates drug delivery • Drug delivery systems can sustain release, enhance uptake and diffusion, and improve efficacy of ocular therapeutics • Studying ocular therapeutics in higher order animals is imperative in demonstrating clinical translatability [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the efficacy and clinical outcomes of a one-way fluid-air exchange procedure for the treatment of postvitrectomy diabetic vitreous hemorrhage in patients with proliferative diabetic retinopathy. Methods: This retrospective study included 233 patients with proliferative diabetic retinopathy, who underwent vitrectomy. A one-way fluid-air exchange procedure was performed in 24 eyes of 24 (10.30%) patients with persistent vitreous cavity rebleeding after the operation. Preprocedural and postprocedural best-corrected visual acuity values were achieved. Complications occurring during and after the procedure were analyzed. Results: Significant visual improvement was observed 1 month after the one-way fluid-air exchange procedure (2.62 ± 0.60 LogMAR at baseline vs. 0.85 ± 0.94 LogMAR at postprocedure, p<0.0001). Moreover, 19 (79.17%) eyes needed the procedure once, and 5 (20.83%) eyed had the procedure more than twice. In 3 (12.50%) eyes, reoperation was eventually required because of persistent rebleeding despite several fluid-air exchanges. No complication was observed during the follow-up. Conclusions: The one-way fluid-air exchange procedure can be an excellent alternative to re-vitrectomy for patients with proliferative diabetic retinopathy suffering from postvitrectomy diabetic vitreous hemorrhage by removing the hemorrhagic contents directly and achieving fast recovery of visual function without apparent complications. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos Brasileiros de Oftalmologia is the property of Arquivos Brasileiros de Oftalmologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to describe the computed tomographic (CT) dimensions and the contrast attenuation of the eye in Jeju horses and Thoroughbreds. We evaluated the CT images of 10 Jeju horses and 6 Thoroughbreds without ocular abnormalities to assess the ocular dimensions and contrast attenuation. The following measurements showed significant differences between Jeju horses and Thoroughbreds (P<0.05): the diameters of the lens, globe, posterior segment, orbital fossa, and lateromedial distance of the anterior chamber; and the Hounsfield units of the vitreous body. This study describes the CT anatomical characteristics of Jeju horses and Thoroughbreds and the differences between the two breeds and provides useful information for understanding and evaluating of the eyes of Jeju horses through a CT scan. [ABSTRACT FROM AUTHOR]

Glaucoma is a multifactorial pathology involving the immune system. The subclinical immune response plays a homeostatic role in healthy situations, but in pathological situations, it produces imbalances. Optical coherence tomography detects immune cells in the vitreous as hyperreflective opacities and these are subsequently characterised by computational analysis. This study monitors the changes in immunity in the vitreous in two steroid-induced glaucoma (SIG) animal models created with drug delivery systems (microspheres loaded with dexamethasone and dexamethasone/fibronectin), comparing both sexes and healthy controls over six months. SIG eyes tended to present greater intensity and a higher number of vitreous opacities (p < 0.05), with dynamic fluctuations in the percentage of isolated cells (10 µm2), non-activated cells (10–50 µm2), activated cells (50–250 µm2) and cell complexes (>250 µm2). Both SIG models presented an anti-inflammatory profile, with non-activated cells being the largest population in this study. However, smaller opacities (isolated cells) seemed to be the first responder to noxa since they were the most rounded (recruitment), coinciding with peak intraocular pressure increase, and showed the highest mean Intensity (intracellular machinery), even in the contralateral eye, and a major change in orientation (motility). Studying the features of hyperreflective opacities in the vitreous using OCT could be a useful biomarker of glaucoma. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Clinical Healthcare is the property of Chinese Journal of Clinical Healthcare and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article discusses a case of human ocular dirofilariasis in Poland. Dirofilariasis is a zoonotic disease caused by filarial parasites, with dogs being the main reservoir. The disease is transmitted by mosquitoes, and humans are accidental hosts. The patient in this case presented with symptoms in the right eye and a subconjunctival infestation was discovered. The worm was surgically removed, and the patient underwent follow-up examinations. The article also provides information on the lifecycle of the parasite, other potential vectors, and the diagnosis and treatment of dirofilariasis. [Extracted from the article]

Retinal detachment (RD) is the most serious problem of modern ophthalmology, often leading to a decrease or irreversible loss of visual functions. The literature review is devoted to the latest trends in the study of the mechanisms of development and course of rhegmatogenous retinal detachment (RRD) against the background of proliferative vitreoretinopathy. In the pathogenesis of RD, there are five theories, as well as nine main risk factors for development. It is known that the contact between the retinal neuroepithelium and the retinal pigment epithelium is maintained by physical and metabolic forces, as well as by the friction force of the outer segments of photoreceptors and RPE cells. With synchisis and simultaneous syneresis, vitreous detachment develops, with increased traction forces and the possible development of RRD. Retinal detachment is the most serious problem of modern ophthalmology, often leading to a decrease or irreversible loss of visual functions. The review of the literature is devoted to the latest trends in the study of the mechanisms of development and course of rhegmatogenous retinal detachment against the background of proliferative vitreoretinopathy. In the pathogenesis of RD, there are five theories, as well as nine main risk factors for development. It is known that the contact between the retinal neuroepithelium and the retinal pigment epithelium is maintained by physical and metabolic forces, as well as by the friction force of the outer segments of photoreceptors and RPE cells. With synchisis and simultaneous syneresis, vitreous detachment develops, with an increase in traction forces and the possible development of RRD. The presence of a retinal tear rarely leads to RRD. It has been established that a pronounced traction effect, rather than a through rupture of the retina, is a key factor in the development and progression of RRD. Traction occurs in the course of proliferative vitreoretinopathy and the epiretinal layer of the vitreum remaining in the posterior vitreous detachment. With the development of detachment, damage to the hematoophthalmic barrier occurs, leading to the release of cells into the vitreous cavity that affect the development of PVR (epi-, sub- and intraretinally) with the formation of an epiretinal membrane. At the same time, communication with the choroid is lost, hypoxia and acidosis develop. ERMs formed during retinal detachment include glial cells and their subtypes — fibrous astrocytes, Muller cells, microglia, hyalocytes, RPE cells, fibroblasts and myofibroblasts. However, the leading role in the formation and development of ERM belongs to Muller cells and astrocytes. Also involved in the pathological process of ERM formation are: transforming growth factor β2, fibroblast growth factor, nerve growth factor, vascular endothelial growth factor, platelet growth factor, laminin, fibronectin, thrombospondin-1, osteonectin, transcription factor. Against the background of ROS, one should not forget about the change in the chemical composition of the vitreous body (increased content): serum albumin, transferrin, antithrombin III, α1-antichymotrypsin, α1-antitrypsin, α2-HS-glycoprotein, hemopexin, transthyretin, apolipoprotein A1, and fibrinogen

Background. The introduction of intravitreal injections of melphalan (IVIM) has significantly improved the efficacy of retinoblastoma treatment and the prognosis for eye preservation. Objectives. To evaluate the results of using IVIM to treat retinoblastoma vitreous seeding. Materials and methods. This was a clinical, retrospective, single-center study. Twenty-six children (27 eyes) who met all of the following inclusion criteria qualified for the study: 1) active vitreous seeding at the time of retinoblastoma diagnosis; 2) IVIM performed between 1 January 2017 and 30 September 2020; and 3) a minimum follow-up period of 12 months since the last IVIM. Doses of 20-40 µg melphalan per injection were used. Results. The eye observation period from the last IVIM to the last ophthalmic examination averaged 32.41 months (median 30.00; range 13.00-56.00). Success (no active tumors in the vitreous body) was achieved in 24 eyes (88.9%), and a doubtful result (recurrence in the retina with a difficult-to-determine etiology) in 2 eyes (7.4%). In 1 eye (3.7%), despite treatment, active tumors were still present in the vitreous body. Out of all 27 eyes, 4 eyeballs were removed, but the direct cause of enucleation was not vitreous seeding. There were no complications in the form of intraocular inflammation, extraocular retinoblastoma or distant metastases. There was 1 case of anterior uveitis and 1 case of cataract. Conclusions. The IVIM is a highly effective and safe form of treatment for retinoblastoma vitreous seeding. [ABSTRACT FROM AUTHOR]

Congenital malformations of the eye represent a wide and heterogeneous spectrum of abnormalities that may be part of a complex syndrome or be isolated. Ocular malformation severity depends on the timing of the causative event during eye formation, ranging from the complete absence of the eye if injury occurs during the first weeks of gestation, to subtle abnormalities if the cause occurs later on. Knowledge of ocular malformations is crucial to performing a tailored imaging protocol and correctly reporting imaging findings. Together with the ophthalmologic evaluation, imaging may help frame ocular malformations and identify underlying genetic conditions. The purpose of this pictorial review is to describe the imaging features of the main ocular malformations and the related ophthalmologic findings in order to provide a clinico-radiological overview of these abnormalities to the clinical radiologist. Sight is a crucial sense for children to explore the world and relate with their parents from birth. Vision impairment or even blindness secondary to ocular malformations deeply affects children's growth and quality of life. [ABSTRACT FROM AUTHOR]

Background: The importance of communicating the anterior chamber and vitreous cavity for managing malignant glaucoma (MG) is widely recognized. This study investigated the impact of improved minimally invasive anterior vitrectomy (IAV) on the prognosis of MG. Methods: This retrospective interventional study included patients with MG who underwent conventional surgery or improved minimally IAV in Nanchang Aier Eye Hospital between January 2011 and April 2021. For the improved step, a small amount of triamcinolone acetonide was injected into the vicinity of the iris. Then, the residual vitreous body adhering to triamcinolone acetonide was excised. Comparisons were made using repeated measures ANOVA, t-test, and chi-squared test. Results: Thirty-one eyes from 26 patients were included: 15 eyes from 13 patients in the conventional group and 16 eyes from 13 patients in the IAV group. The 1-week, 1-month, and 3-month intraocular pressure (IOP) and the 3-month mean central anterior chamber depth were comparable between the two groups (all P > 0.05). The conventional group showed one eye with intraoperative vitreous hemorrhage and two eyes with postoperative re-shallowing of the anterior chamber; such events did not occur in the IAV group, and none developed corneal endothelial decompensation, IOL deviation, suprachoroidal hemorrhage, or retinal detachment during treatment and follow-up. Conclusion: Patients with MG who undergo improved minimally IAV might have similar postoperative IOP and central anterior chamber depth compared with conventional surgery but with reduced complications such as intraoperative vitreous hemorrhage and postoperative re-shallowing of the anterior chamber. Improved minimally IAV might be an alternative surgery for MG. [ABSTRACT FROM AUTHOR]

Due to the scarcity of literature data on the DNA content of different human tissues, this study aimed to isolate DNA from different tissues and fluids of the human body together with the determination of its content in the samples studied. Material was collected and tests were performed between 1990 and 2010, during autopsies performed for prosecutor's offices in the Department of Forensic Medicine. Goiter and thyroid cancer tissues were obtained from the Department of General Surgery, Gastroenterology and Endocrinology of Wroclaw Medical University. Isolated samples were measured spectrophotometrically, yielding an R 260/280 nm between 1.5 and 1.6. In some cases (when a sufficiently pure preparation could not be obtained), isolation was continued using the silica-based commercial QIAquick PCR Purification Kit (Qiagen). If the sampling tissues showed signs of decomposition such as bad odour or colour, the results were calibrated by Real-Time PCR, using the Quantifiler DNA assay (Thermo Fisher Scientific, Applied Biosystems). The results have shown that the maximum amount of genetic material was obtained from hair roots, adrenal glands, gonads and lymph nodes. The lowest DNA content per gram or milliliter of tissue or body fluid was found in adipose tissue, blood, saliva, bile, sweat, tears and the vitreous body of the eye. The presented findings indicate the best sources of high-quality DNA from the human body: gonads, kidneys, muscle (including heart), blood and bones (after decalcification). [ABSTRACT FROM AUTHOR]

Introduction: Personalized medicine and patient-tailored drug dosing have been substantiated through thousands of clinical studies, demonstrating their safety and efficacy. The principle: "as much as necessary, as little as possible" is widely spread. Quantities and doses are therefore adjusted individually. This is not the case for intravitreal injections in the context of retinal diseases. Intravitreal injections are not adjusted in relation to the vitreous volume. The vitreous body is described as "approx. 4 cm3" in the literature. Methods: In this retrospective observational study, we included 72 eyes of patients who had undergone magnetic resonance imaging (MRI) of the orbit and biometry measurements of the anterior chamber depth (ACD) and axial length. After segmentation of the volume data, the vitreous volume was extracted by voxel integration, and a simple prediction model was derived to determine the vitreous volume from the axial length (AL) measurement with AL3·π/6·(0.76 + 0.012·(AL-24). This is the volume of a sphere AL3·π/6 and a correction term 0.76 + 0.012·(AL-24) to account for the portion of the vitreous in the entire globe and the proportional increase of the vitreous portion for long (myopic) eyes. Results: Emmetropic eyes with an axial length of 22.50–23.50 mm had a vitreous volume of around 4.5–5.5 cm3. Myopic eyes with an axial length of 30.00 mm had a calculated vitreous volume of 9.0–10.0 cm3. Hypermetropic eyes with an axial length of 20.00 mm showed a vitreous volume of 3.0–4.0 cm3. Conclusions: By implementing the new calculation formula on the IOLCON website, it will be easy to get the exact individual vitreous volume. The data could be used by retinal surgeons prior to surgery. The knowledge of anatomical dimensions and exact individual vitreous volume seems to be important for gas and silicone oil fillings. With the newly derived knowledge, multicentric studies can evaluate the impact of the dose in intravitreal therapies. Patient-tailored dosing could prevent side effects and improve effectiveness. [ABSTRACT FROM AUTHOR]

Background: Neuroinflammation and mitochondrial dysfunction play crucial roles in retinal ischemia and reperfusion (IR) injury. Recent studies have identified mitochondrial function as a promising target for immunomodulation. Empagliflozin (EMPA), an anti-diabetic drug, has exhibited great potential as both an anti-inflammatory agent and a protector of mitochondrial health. This study aimed to assess the therapeutic efficacy of EMPA in retinal IR injury. Methods: To evaluate the protective effects of EMPA, the drug was injected into the vitreous body of mice post-retinal IR. Single-cell RNA sequencing (scRNA-seq) analysis was conducted to uncover the underlying mechanisms, and the results were further validated through in vivo and in vitro experiments. Results: EMPA effectively protected retinal ganglion cells (RGCs) from IR injury by attenuating local retinal inflammation. The scRNA-seq analysis revealed that EMPA downregulated the nucleotide-binding domain and leucine-rich repeat containing protein 3 (NLRP3) signaling pathway and restored mitochondrial dynamics by upregulating the expression of mitochondrial fusion-related genes, Mitofusin 1 (Mfn1) and optic atrophy 1 (Opa1). These findings were further corroborated by Western blotting. In vitro experiments provided additional insights, demonstrating that EMPA suppressed lipopolysaccharide (LPS)-induced cell inflammation and NLRP3 inflammasome activation. Moreover, EMPA enhanced mitochondrial fusion, neutralized mitochondrial reactive oxygen species (mtROS), and restored mitochondrial membrane potential (MMP) in BV2 microglia. Notably, genetic ablation of Mfn1 or Opa1 abolished the anti-inflammatory effects of EMPA. Conclusions: Our findings highlight the positive contribution of Mfn1 and Opa1 to the anti-inflammatory therapeutic effect of EMPA. By restoring mitochondrial dynamics, EMPA effectively mitigates microglia-mediated neuroinflammation and prevents RGC loss in retinal IR injury. [ABSTRACT FROM AUTHOR]