Outcomes of a Foldable Capsular Vitreous Body Implantation: A Retrospective Study

Background. The vitreous body is an important part of the ocular body fluid. A foldable capsular vitreous body (FCVB) is designed to treat chronic adverse complications in severe ocular trauma and silicone oil-dependent eyes. This study is aimed at investigating a method for implanting an FCVB, its postoperative efficacy, and clinical value. Methods. A retrospective analysis was performed on data from 18 patients who underwent vitrectomy and FCVB implantation for severe ocular trauma and silicone oil-dependent eyes between March 2019 and May 2020. All treated eyes underwent clinical examinations involving the best-corrected visual acuity, intraocular pressure, FCVB position, anterior segment photography, and wide-angle fundus photography regularly after surgery. Results. Eighteen eyes from 18 patients were enrolled in this study. A total of 2.00–4.20 ( 3.46 ± 0.78 ) ml of silicone oil were injected into the FCVB during surgery. The patients were followed up at 1, 2, and 4 weeks and 3, 6, and 12 months after surgery. Twelve months after surgery, visual acuity improved in 7 (38.89%) eyes. In contrast, 10 (55.56%) eyes showed no obvious improvement, and 1 (5.56%) eye had decreased vision. Intraocular pressure at 12 months was 10.13 ± 3.52 mmHg, which was comparable to that before the surgery ( t = 0.38 , P = 0.71 ). The anterior chamber depth examined by slit lamp was 2.00–3.00 cornea thickness (CT) in 7 eyes, 1.00–2.00 CT in 2 eyes, and <1.00 CT in one eye. The anterior chamber disappeared in eight eyes. There were eight eyes with clear cornea, four eyes with localized opacity, and two eyes with obvious gray-white opacity. There was no case of severe FCVB deflection, rupture, or exposure during the observation period. Conclusion. FCVB implantation is an effective and safe treatment for eyes with severe ocular trauma and silicone oil-dependent eyes. It may support retinal reattachment, slow down eyeball atrophy, reduce the risk of chronic adverse complications such as corneal endothelial decompensation, and maintain intraocular pressure and preoperative visual function.

Evaluation of the long-term effect of foldable capsular vitreous bodies in severe ocular rupture

AIM: To evaluate the long-term effect of foldable capsular vitreous body (FCVB) in the treatment of severe ocular rupture to provide a practical basis for clinical selection. METHODS: A total of 26 patients (26 eyes), 23 men and 3 women, with severe ocular rupture who underwent FCVB implantation between March 2018 and September 2018 were retrospectively analysed. All open ocular wounds located in zone III, with preoperative visual acuity grade IV and above (Snellen less than 4/200). The best corrected visual acuity (BCVA), intraocular pressure (IOP), cornea, anterior chamber, iris, lens, choroid, and retina were evaluated before and after the surgery. The subjective feeling and the location of FCVB were also assessed. RESULTS: The average age of the 26 patients was 36y (20-60y). Postoperative follow-up was from 10 to 14mo. At the end of follow up, BCVA was light perception (LP) in 10 cases, no light perception (NLP) in 13 cases, hand motions (HM) in 3 cases. IOP was 11±5 mm Hg. Corneal degeneration was in 3 cases and corneal endothelial dystrophy was in 7 cases. Shallow anterior chamber was in 8 cases and hyphema was in 8 cases. Organized membrane in the pupil was in 14 cases. Epiphora occurred in 3 cases. FCVB drainage tube exposed in 3 cases. All FCVBs were in their normal location and no rejection occurred. CONCLUSION: FCVB implantation is a long-term effective treatment and may provide a practical selection for severe ocular rupture.

Transplantation of Bone Marrow Mesenchymal Stem Cells (BMSCs) Overexpressing Circular Zinc Finger Protein 609 Alleviates Diabetic Retinopathy

Diabetic retinopathy (DR) is a chronic complications and its pathogenesis remains unclear. This study aims to elucidate the underlying mechanism by how bone marrow mesenchymal stem cells (BMSCs) affects DR development in a rat model. A rat model of DR was established and injected with BMSCs overexpressing Cir-ZNF609 and shRNA Cir-ZNF609 to vitreous body followed by analysis of the retinal vascular permeability and macular retinal layers thickness, and the levels of HIF-1α, ICAM-1 and VEGF in rat retina by ELISA and immunohistochemistry. Injection of BMSCs overexpressing Cir-ZNF609 resulted in decreased HIF-1α ICAM-1 and VEGF expression, amelioration of retinal ganglion choriocapillaris injury and reducing ganglion cells. Twelve weeks after treatment, neovascularization took place and fibroblasts appeared with some nucleus disappearing and pigment taking off. Besides, permeability also elevated in the presence of overexpressing Cir-ZNF609 and penetration rate for Evans blue (16.36+3.25, 15.45±3.46 μg/g) was lower than healthy rats (28.66±2.08, 32.24±4.36 μg/g) and controls (26.93±3.03, 33.49±5.02 μg/g) (p < 0.01). Moreover, upregulation of Cir-ZNF609 decreased retinal thickness and macular volume in DR rats (p < 0.05). In conclusion, intravitreal injection of mouse BMSCs overexpressing Cir-ZNF609 alleviates retinal injury and decreases retinal thickness and macular volume, and enhances neovascularization. These evidence provides a novel insight into gene therapy for DR.

Structural basis for transthyretin amyloid formation in vitreous body of the eye

Amyloid transthyretin (ATTR) amyloidosis is characterized by the abnormal accumulation of ATTR fibrils in multiple organs. However, the structure of ATTR fibrils from the eye is poorly understood. Here, we used cryo-EM to structurally characterize vitreous body ATTR fibrils. These structures were distinct from previously characterized heart fibrils, even though both have the same mutation and type A pathology. Differences were observed at several structural levels: in both the number and arrangement of protofilaments, and the conformation of the protein fibril in each layer of protofilaments. Thus, our results show that ATTR protein structure and its assembly into protofilaments in the type A fibrils can vary between patients carrying the same mutation. By analyzing and matching the interfaces between the amino acids in the ATTR fibril with those in the natively folded TTR, we are able to propose a mechanism for the structural conversion of TTR into a fibrillar form.

Surgical treatment of damage to the posterior capsule of the lens after laser vitreolysis

Damage to the posterior capsule of the lens after laser vitreolysis causes the formation of traumatic cataracts and a decrease in visual acuity. The search for surgical methods of treating such complications is relevant. Purpose. To develop and improve the technique of posterior capsulorexis during phacoemulsification and implantation of IOL combined with vitrectomy in the presence of an initial injury of the posterior lens capsule. Material and methods. Clinical case - a patient came to the clinic with complaints about a decrease in visual acuity and quality after laser vitreolysis performed in another clinic. Observed the damage of the posterior capsule of the lens. The operation was performed according to the developed technique. Results. A method of primary posterior capsulorexis during phacoemulsification and implantation of IOL after vitreolysis, combined with vitrectomy, is proposed. Achieved high visual acuity after the operation, OD=1.0. Conclusions. 1) The developed technique of primary posterior capsulorexis is safe and allows partially preserving the posterior capsule of the lens, while forming a «window» in the area of damage, and implanting the IOL into a capsule bag. 2) The installation of scleral ports during primary posterior capsulorexis makes it possible to successfully combine this operation with vitrectomy and prevent the displacement of lens fragments to the fundus. Key words: сataract, posterior capsulorexis, laser vitreolysis, phacoemulsification, pseudophakia, IOL, vitrectomy, vitreous body.

Prevalence and Associations of Asteroid Hyalosis: The Beijing Eye Study

Background: To determine the prevalence and associations of asteroid hyalosis (AH) in a Chinese population-based cohort.Methods: The population-based Beijing Eye Study 2011 included 3468 individuals with a mean age of 64.6 ± 9.8 years (range: 50-93 years). AH is a condition in which small yellow-white, spherical particles known as asteroid bodies (ABs) are present within the vitreous body.Results: Fundus photographs were gradable in 3419 subjects. AH was detected in 65 (0.9%, 95% CI: 0.7%, 1.2%) eyes of 53 (1.5%, 95% CI: 1.1%, 1.9%) subjects. AH was bilateral in 18.9%. Mean age of all subjects with AH was 69.2± 9.5 years (median, 71.0 years; range, 51–91 years), mean refractive error was 0.63±1.53D (median, 0.75 D; range, -4.12 to 4.00D). In multivariate analysis, prevalence of AH was associated with elder age (P=0.014, OR 1.057), thicker lens (P=0.034, OR 3.843), higher refractive error (P=0.016, OR 1.401).Conclusions: In adult Chinese in Beijing, the prevalence of AH was 0.9% for eyes or 1.5% for subjects. AH was associated with elder age, thicker lens and higher refractive error. It does not support previous observations of an association of AH with diabetes or other systemic indicators.

Diagnostic possibilities of accurate determination of the time since death on the concentration of electrolytes in the vitreous body of the human eye

In this paper the results of modern scientific researches are analyzed and the possibilities of the method of establishing the amount of K+ and Na+ in the vitreous body (VB) of a person for solving problems of practical forensic medicine are studied. The aim of the work. To investigate the possibilities of accurately establishing the time since death (TSD) by determining the amount of electrolytes (K+ and Na+) of human VB. Materials and methods. VB samples from 120 deaths due to cardiovascular pathology (exclusion criteria: eyeball injuries, traumatic brain injury, exogenous intoxications) were studied. The study of the test material was performed on an analyzer of electrolytes and gases ROCHE COBAS B121. The main task was to analyze and establish the dependence of the change in the amount of K+ and Na+ of the VB on the TSD. Statistical processing of the obtained results was performed using Statistica software. Results. In all cases, on average in the first 6 hours, its amount was 7,4 mmol/l, after 6-12 hours – 9,8 mmol/l, after 12-18 hours – 12,1 mmol/l, after 18-24 hours – 16,5 mmol/l, after 24-36 hours – 20,2 mmol/l, after 36-48 hours – 25,3 mmol/l. The amount of Na+ ranged from 120 to 200 mmol/l. Conclusions. It is established that the number of electrolytes of the VB of the human eye naturally changes with increasing postmortem interval, which allows to use this technique to determine the TSD. In particular, the accuracy of setting the DNS by the number of K+ – 4-6 hours between 1 and 18 hours after death. There is an increase in the range of accuracy at a later date of the TSD.

Corynebacterium ocular infection after Baerveldt glaucoma implant surgery: treatment involving immediate tube withdrawal and temporary subconjunctival tube placement: a case report

Background We report a case of Corynebacterium endophthalmitis secondary to tube exposure following Baerveldt glaucoma implant surgery that was successfully treated with prompt tube withdrawal and temporary subconjunctival tube placement without removing the glaucoma drainage device. Case presentation A 65-year-old Japanese man with secondary glaucoma underwent glaucoma drainage device surgery with a donor scleral patch graft in the inferonasal quadrant of his right eye. Ten months after surgery, he presented with tube exposure due to dehiscence of the overlying conjunctiva and erosion of the scleral patch graft. Eleven days later, mild inflammation was found in the anterior chamber and anterior vitreous body, with the root of the tube surrounded by a plaque at the site of insertion in the anterior chamber. He was diagnosed with infectious endophthalmitis secondary to tube exposure. Two days later, since medical therapy was ineffective, the tube was withdrawn from the anterior chamber and irrigated with a polyvinyl alcohol-iodine solution, and the tube was tucked into the subconjunctival space. Complete resolution of the infection was achieved 1.5 months later. The tube was reinserted nasally into the anterior chamber and covered with a scleral patch graft and a free limbal conjunctival autograft. Thereafter, there has been no recurrence of infection or tube exposure. Twenty eight months after tube reinsertion, his right best-corrected visual acuity was 20/50 and intraocular pressure was 12 mmHg. Conclusion Prompt tube withdrawal and temporary subconjunctival tube placement followed by tube reinsertion may be effective for endophthalmitis associated with tube exposure after glaucoma drainage device surgery.