Foldable Capsular Vitreous Body Research Articles

Study on maintenance of eyeball morphology by foldable capsular vitreous body in severe ocular trauma

ObjectivesTo explore the feasibility and safety of using a foldable capsular vitreous body (FCVB) in managing severe ocular trauma and silicone oil-dependent eyes.MethodologyThis is a retrospective study of 61 ocular trauma patients (61 eyes) who presented to the Department of Eye Emergency, Hebei Eye Hospital from May 1, 2018, to May 31, 2019, including 51 male patients (51 eyes) and 10 female patients (10 eyes) with an average age of 44.98 ± 14.60 years old. The oldest patient was 75 years old, and the youngest was 8 years old. These cases represented 51 eyes with severe eyeball rupture and 10 eyes with severe, complicated ocular trauma, which became silicone oil-dependent after the operation. These patients received FCVB implants, and data regarding their visual acuity, intraocular pressure, changes in eye axis, cornea, retina, and FCVB state were recorded after the operation.ResultsIn all patients, the FCVB was properly positioned and well supported with the retina. All 61 patients cleared a follow-up window of 1–36 months with no reports of important changes in their visual acuity. Among the patients, 91.8% reported normal intraocular pressure, the retinal reattachment rate reached 100%, and the eyeball atrophy control rate reached 100%. There was no report of rupture of the FCVB, allergies to silicone, intraocular infection, intraocular hemorrhage, silicone oil emulsification, or sympathetic ophthalmia.ConclusionsFoldable capsular vitreous bodies (FCVBs) designed to mimic natural vitreous bodies are suitable as long-term ocular implants that can provide sustained support for the retina without the need for any special postoperative postures. Their barrier function may effectively prolong the retention time of the tamponade and prevent various complications caused by direct contact of the eye tissues with the tamponade.

Clinical Efficacy and Safety of Foldable Capsular Vitreous Body Implant Surgery in 22 Cases of Silicone Oil-dependent Eyes.

This study aimed to evaluate the clinical efficacy and safety of foldable capsular vitreous body (FCVB) implant surgery in silicone oil-dependent eyes. A total of 22 participants with silicone oil-dependent eyes who received treatment with FCVB implant surgery between January 2019 and June 2020 were included in this retrospective study. The intraocular pressure (IOP), best-corrected visual acuity (BCVA), demographic data, and any recorded complications were evaluated. The postoperative IOP (12.73±4.20 mmHg) was significantly improved (P=0.03) compared to the preoperative IOP (10.23±3.69 mmHg) (the main endpoint). There was no significant difference (P=0.33) in the final BCVA preoperation and 3rd month postoperation (the secondary endpoint). The most common postoperative complication was hyphema. Other common postoperative complications included corneal opacity, a shallow anterior chamber, and a low IOP. FCVB implant surgery is a safe and effective method for treating silicone oil-dependent eyes; however, attention should be paid to the prevention and timely treatment of complications.

Advances in Polysaccharide- and Synthetic Polymer-Based Vitreous Substitutes

The vitreous humour is a gel-like structure that composes the majority of each eye. It functions to provide passage of light, be a viscoelastic dampener, and hold the retina in place. Vitreous liquefaction causes retinal detachment and retinal tears requiring pars plana vitrectomy for vitreous substitution. An ideal vitreous substitute should display similar mechanical, chemical, and rheological properties to the natural vitreous. Currently used vitreous substitutes such as silicone oil, perfluorocarbon liquids, and gases cannot be used long-term due to adverse effects such as poor retention time, cytotoxicity, and cataract formation. Long-term, experimental vitreous substitutes composed of natural, modified and synthetic polymers are currently being studied. This review discusses current long- and short-term vitreous substitutes and the disadvantages of these that have highlighted the need for an ideal vitreous substitute. The review subsequently focuses specifically on currently used polysaccharide- and synthetic polymer-based vitreous substitutes, which may be modified or functionalised, or employed as the derivative, and discusses experimental vitreous substitutes in these classes. The advantages and challenges associated with the use of polymeric substitutes are discussed. Innovative approaches to vitreous substitution, namely a novel foldable capsular vitreous body, are presented, as well as future perspectives related to the advancement of this field.

Study on the efficacy and safety of foldable capsular vitreous body in the severe retinal detachment eyes

BackgroundThis study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body (FCVB) in severe retinal detachment eyes.MethodsA retrospective study in retinal detachment eyes was performed at Shandong Provincial Hospital Affiliated to Shandong First Medical University. A standard three-port pars plana vitrectomy was performed, and the FCVB was triple folded and implanted into the vitreous cavity. The silicone oil (SO) was then injected into the capsule of the FCVB to support the retina and eye. During the follow-up period, The treated eyes were examined by ophthalmoscopy, fundus photography, and tonometry. B-scan ultrasonography, optical coherence tomography (OCT), and computed tomography (CT), were also performed.ResultsFrom May 2020 to November 2021, 31 cases with severe retinal detachment were enrolled in the study. The postoperative follow-up time gradient ranged from 1 to 72 weeks, At various observation time points during the 72 weeks after surgery, The postoperative IOP was maintained at around 10 mmhg at various time points, with a slight decrease compared to the preoperative IOP (14.2 ± 4.6 mmHg n = 18), and was statistically significant. 9 of 31 patients had clear refractive media, both fundus and OCT showed retinal reattachment, OCT showed the 200 μm thick FCVB capsule support retina. The remaining 22 patients with unclear refractive media, B-scan showed arcuate hyperechoes in front of the retina. There was also no significant difference in visual acuity compared to preoperative. The FCVB was well positioned in the vitreous cavity, and no serious complications such as endophthalmitis, glaucoma, silicone oil emulsification, product exposure, or sympathetic uveitis were found.ConclusionsFCVB has retinal support with certain ability to maintain IOP and eye morphology and avoid eye removal in patients with severe retinal detachment during the 72-week observation period.

Clinical Application of Foldable Capsular Vitreous Bodies in the Treatment of Severe Ocular Trauma and Silicone Oil Dependent Eyes.

This study aimed to assess the application of a foldable capsular vitreous body (FCVB) in the treatment of severe ocular trauma and silicone oil (SO) dependent eyes. A retrospective analysis was performed on the clinical application of FCVB in the treatment of severe ocular trauma and SO dependent eyes. The results of best-corrected visual acuity and intraocular pressure (IOP) evaluation, B-scan ultrasonography or color Doppler ultrasonography, ultrasound biomicroscopy, and anterior segment photography were recorded during follow-up. A paired t-test was used to compare the difference in IOP before and after FCVB implantation. Seven eyes of seven patients were included in the 6-month follow-up. In all cases, B-scan ultrasonography and ultrasound biomicroscopy showed that FCVB adapted closely to the globe wall and ciliary body, thus supporting the retina. Visual acuity did not improve, except in one case from LP to HM. The mean ± SD IOP was 8.5 ± 1.90 mm·Hg prior to FCVB implantation and 10.43 ± 0.98 mm·Hg after implantation, with no significant difference between these measurements (P=0.095). Five of the seven patients developed differing degrees of corneal opacity and keratopathy. FCVB implantation may be a safe and effective method for the treatment of severe ocular trauma and SO dependent eyes. However, FCVB cannot prevent the phthisis of the traumatic eyes. In addition, corneal opacity and keratopathy are potentially serious complications after surgery. Appropriate case selection and proper surgical timing are required for further investigation.

Evaluation of Foldable Capsular Vitreous Body Implantation Surgery.

BackgroundFoldable capsular vitreous body (FCVB), a novel artificial vitreous substitute product, has been used clinically in recent years. The aim of this study was to evaluate the outcomes and complications of FCVB implantation surgery during the postoperative period.MethodsWe performed a prospective, nonrandomized study from November 2021 to March 2022. Eight patients with severe retinal detachment that could not be easily reattached were included in this study. Before and after surgery, visual acuity (VA), intraocular pressure (IOP), slit-lamp microscopy, optical coherence tomography (OCT), B-scan and CT were performed.ResultsAfter the operation, the FCVB was well distributed in the vitreous cavity and supported the retina according to the B-scan and CT images. During the follow-up period, no vitreous hemorrhage or retinal detachment was found in any of the patients. On the first postoperative day, the average IOP increased from 9.6 ± 7.7 mmHg preoperatively to 13.8 ± 14.3 mmHg. Although the IOP of two patients fell outside the normal range, IOP was finally held steady after the fifth postoperative day in all cases. In addition, three patients (37.5%) experienced eye ache, and after taking a Saridon tablet, the pain was greatly alleviated. Moreover, no adverse events, such as silicone oil (SO) spillage and emulsification or serious complications, were observed.ConclusionThe current vitreous substitute FCVB is effective and safe for treating complicated retinal detachments in ophthalmic applications. Further multiple-center clinical designs should focus on indications and complications of FCVB during long-term follow-up periods.

FOLDABLE CAPSULAR VITREOUS BODY IMPLANTATION FOR COMPLICATED RETINAL DETACHMENT CAUSED BY SEVERE OCULAR TRAUMA.

To explore the effectiveness, safety and psychological impact of foldable capsular vitreous body (FCVB) implantation for complicated retinal detachment caused by severe ocular trauma. This was a prospective, single-arm, surgical interventional case series study. A standard 3-port 23-gauge pars plana vitrectomy was performed, and the FCVB was implanted into the vitreous cavity. Observed indicators, including the best-corrected visual acuity, intraocular pressure (IOP), retinal reattachment, complications, and patient satisfaction, were analyzed to evaluate the study. A total of 28 cases (eyes) were enrolled, with a mean follow-up of 16.93 ± 9.67 months and an average age of 51.11 ± 10.14 years, including 22 men (78.57%). The FCVB was successfully implanted, and the retina was reattached in all cases. The postoperative best-corrected visual acuity improved in 7 cases, and remained unchanged in 21 cases ( P > 0.05). The average IOP was 7.01 ± 2.43 mmHg before surgery and 8.54 ± 2.93 mmHg after surgery ( P < 0.05). Complications such as FCVB displacement, endophthalmitis, secondary glaucoma, silicone oil emulsification, and escape did not occur during the follow-up period. Patients with FCVB implantation are highly satisfied. Most patients feel hope, positive, and optimistic about life. Foldable capsular vitreous body implantation for complicated retinal detachment caused by severe ocular trauma is effective and safe, and it allows patients to face life positively and optimistically.

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.

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. 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. 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. FCVB implantation is a long-term effective treatment and may provide a practical selection for severe ocular rupture.

Preliminary clinical application of foldable capsular vitreous body in severe silicone oil-dependent eyes.

To investigate the clinical safety and efficacy of foldable capsular vitreous body (FCVB) in the treatment of severe silicone oil-dependent eyes. Five patients (5 eyes) of severe silicone oil-dependent eyes underwent FCVB implantation from December 2019 to July 2020. The preoperative and postoperative visual acuity, intraocular pressure, corneal conditions, postoperative retinal reattachment, and FCVB status were observed. The patients were followed up for 12-15 months. A total of 5 patients (5 eyes) with severe silicone oil-dependent eyes were included, including 3 males and 2 females, with an average age of 32±14 years. The longest silicone oil tamponade time was 8 years, and the shortest was 2 years, with an average of 5±3 years. All patients were safely and successfully implanted with FCVB without severe intraoperative or postoperative complications. Up to the last follow-up, there was no significant change between preoperative and postoperative visual acuity. Before surgery, 4 patients had normal intraocular pressure while 1 patient had ocular hypotension; after surgery, the latter was still at a low level, and the other patients had intraocular pressure in the normal range. The FCVB is a safe, feasible, and effective vitreous substitute to maintain ocular morphology and intraocular pressure without aggravating silicone oil emulsification, retinal displacement, or corneal degeneration during the implantation period of 12-15 months.

Reattachment After Foldable Capsular Vitreous Body Implantation in Severe Retinal Detachment Eyes.

PurposeTo evaluate the clinical effectiveness and safety of foldable capsular vitreous body (FCVB) implantation for severe retinal detachment.MethodsA retrospective analysis was performed on 26 patients with severe ocular trauma and one with recurrent retinal detachment. Clinical data—including surgery success, complications, retinal reattachment, vision, and intraocular pressure (IOP)—were analyzed for patients who underwent 23G pars plana vitrectomy and FCVB implantation combined with silicone oil tamponade.ResultsThe mean follow-up period was 10.44 ± 2.68 months. All surgeries were smooth; the FCVBs were properly positioned and supported the retina well, and the retinal reattachment rate reached 92.59%. At the six-month follow-up, preoperative (1.30 ± 1.20) and postoperative (0.63 ± 0.79) vision was significantly different (t = 3.03, P = 0.005), and the postoperative IOP (7.93 ± 3.57 mm Hg) was lower than the preoperative IOP (13.98 ± 10.72 mm Hg) (t = 2.74, P = 0.01). Among 20 patients followed up for >12 months, preoperative (1.20 ± 0.95) and postoperative (0.75 ± 0.91) visions were significantly different (t = 1.831, P = 0.005), and the postoperative IOP (9.85 ± 6.48 mm Hg) was lower than the preoperative IOP (14.85 ± 12.17 mm Hg) (t = 1.82, P = 0.01). No endophthalmitis, sympathetic ophthalmia, and rejection of FCVB occurred during follow-up.ConclusionsFCVB combined with silicone oil tamponade showed good efficacy and safety in severe retinal detachment treatment during the follow-up period.Translational RelevanceVitreous substitution is deemed a highly challenging and interesting research topic in ophthalmology. Traditional method such as silicone oil tamponade often causes various complications such as silicone oil emulsification, silicone oil migration, and corneal degeneration. The foldable capsular vitreous body as a novel vitreous substitute combined silicone oil injection into it can stay in the eyeball for a long time without obvious complications.

Comparison of Viscoelastic Substance Injection Versus Air Filling in the Anterior Chamber During Foldable Capsular Vitreous Body (FCVB) Implant Surgery: A Prospective Randomized Controlled Trial.

IntroductionTo compare the outcomes of viscoelastic substance injection with air filling in the anterior chamber during foldable capsular vitreous body (FCVB) implant surgery in patients with severe retinal disease.MethodsThirty eyes with severe retinal diseases were randomly divided into two groups. In the viscoelastic group, 0.15-0.2 mL of 1.7% sodium hyaluronate was injected into the anterior chamber after FCVB implantation; in the air group, the anterior chamber was maintained by filling the air after FCVB implant surgery. The eyes of treated patients were examined during a 24-week follow-up appointment. Data, including intraocular pressure (IOP), the difference between preoperative and postoperative IOP, and postoperative complications, were recorded.ResultsData collected from 27 eyes were used in the final analysis. The IOP of the air group was lower than that of the viscoelastic group from the first to third postoperative day (P < 0.01). Moreover, the difference between preoperative and postoperative IOP in the viscoelastic group was significantly smaller than that in the air group from the first to third postoperative day (P < 0.01). After the 1st postoperative week, postoperative IOP values were similar in the two groups (P > 0.05). Postoperative complications in the air group and the viscoelastic group included corneal blood staining (1 eye vs. 0 eyes), transient postoperative diffuse hemorrhage (5 eyes vs. 1 eye), inflammation reaction (9 eyes vs. 4 eyes), and postoperative fibrin exudation (4 eyes vs. 1 eye), respectively.ConclusionThe use of viscoelastic substances in the anterior chamber during FCVB implant surgery was associated with less fluctuation in postoperative IOP and could reduce postoperative complications.Registration NumberChiCTR-TNC-00000396.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12325-021-01840-5.

Clinical observation and perception of foldable capsular vitreous body implantation in 73 cases

Clinical observation and perception of foldable capsular vitreous body implantation in 73 cases

Study on the effectiveness and safety of Foldable Capsular Vitreous Body implantation

BackgroundFoldable capsular vitreous body (FCVB) was designed to treat severe retinal detachment. The aim of this study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body in 1-year follow-up.MethodsA retrospective analysis was conducted for 20 patients with severe ocular trauma or silicone oil (SO) dependent eyes underwent vitrectomy and FCVB implantation in a 1-year follow-up. All treated eyes were peformed clinical examinations involved the visual acuity (VA) examination, Goldmann applanation tonometer, noncontact specular microscopy, fundus photography, B-Scan examination and optical coherence tomography (OCT). The groups were compared with t-test and the McNemar - Bowker test.ResultsIn 1-year follow-up, 20 eyes were evaluated in the study. FCVB well supported the vitreous retina in all treated eyes, and 6 treated eyes achieved retinal reattachment 12 months after FCVB implantation. There were no significant differences in VA before and after FCVB implantation (P = 1.000). In addition, the postoperative IOP markedly elevated from the preoperative IOP of 12.90 ± 7.06 mmHg to 15.15 ± 3.36 mmHg (P = 0.000017). The intraocular pressure (IOP) of 10 eyes maintained at a normal level after surgeries. The other 10 eyes showed slightly lower IOP within the acceptable level. Though two patients developed keratopathy and ocular inflammation respectively, other treated eyes were symmetric with fellow eyes showing satisfactory appearance. Moreover, there was no SO emulsification or leakage happened in the observation.ConclusionsFCVB implantation was an effective and safe treatment in the eyes with severe retinal detachment.

A PILOT CLINICAL STUDY OF TREATING RHEGMATOGENOUS RETINAL DETACHMENT BY SILICONE RUBBER BALLOON SCLERAL BUCKLING.

To evaluate the efficacy and primary safety of treating rhegmatogenous retinal detachment (RRD) using foldable capsular vitreous body scleral buckling. Five patients with simple RRD were treated with foldable capsular vitreous body scleral buckling. B-ultrasound and fundus photography examining of retina reattachment were used to evaluate the postsurgery efficacy. The safety of the treatment was evaluated based on the occurrence of infection, eye pain, diplopia, elevated intraocular pressure, and other serious postoperative complications after surgery. The observation time after the operation was at least 12 weeks. The simple RRD of all five patients was successfully reattached before being evaluating by B-ultrasound and fundus photography after surgery. Visual acuity was enhanced in two patients who were macularly affected. One patient had temporary diplopia and eye movement limitation after surgery. No other complications were recorded. This pilot study determined that foldable capsular vitreous body scleral buckling can be efficacious and safe for simple RRD. The results indicate that this surgery may be a novel alternative to the current extraocular procedures for simple RRD.

Preliminary clinical practice in implantation of foldable capsular vitreous body

Preliminary clinical practice in implantation of foldable capsular vitreous body

Three-Year Efficacy and Safety of a Silicone Oil-Filled Foldable-Capsular-Vitreous-Body in Three Cases of Severe Retinal Detachment.

PurposeWe previously designed a novel foldable capsular vitreous body (FCVB) to treat severe retinal detachment and evaluated its performance in a 1-year follow up study. The purpose of this study was to determine the efficacy and safety of a silicone oil (SO)-filled FCVB in a 3-year follow-up.MethodsStandard three-port pars plana vitrectomy was performed, and the FCVB was triple folded and implanted in the vitreous cavity of three eyes. The SO then was injected into the capsule to support the retina. The eyes were examined using Goldmann applanation tonometry, fundus photography, optical coherence tomography (OCT), noncontact specular microscopy, and ultrasound biomicroscopy over a 3-year implantation period.ResultsAt the 3-year follow-up, retinal reattachment was achieved in all three cases, with steady intraocular pressure. The visual acuity showed slight fluctuations, and it was slightly increased compared to baseline. Optical coherence tomography revealed decreased retinal thickness and an altered retinal structure in the implanted eyes compared to the control eyes. No keratopathy, glaucoma, SO leakage, SO emulsification, or other apparent complications occurred during the observation period.ConclusionThe SO-filled FCVB was effective and safe as a vitreous substitute in three eyes over a 3-year observation period.Translational RelevanceSilicone oil emulsification is a severe complication after retinal detachment surgery. On the basis of animal experiments, we investigated a new strategy and product, the FCVB, to overcome this complication. In this pilot study, FCVB limited SO emulsification and migration. This study could lay the foundation for a further multicenter clinical trial.

Vitreous Substitute: A review of research progress

Retinal detachment is a common ocular disease and one of its main treatment is vitreous surgery followed by injection of proper vitreous substitute, such as air and silicone oil. A good vitreous substitute makes great contribution to the reattachment of retina and reduction of complications while there is no satisfactory vitreous substitute at the moment. Therefore, many researches have been conducted trying to find a perfect substitute after vitrectomy. Hereby, we reviewed the vitreous substitute and their features which have been put to clinical use, as well as those still in research, such as hydrogel and Foldable Capsular Vitreous Body(FCVB). Key words: Vitreous substitute; Vitreous surgery; Silicone oil; Hydrogel

Preliminary study on retinal vascular and oxygen-related changes after long-term silicone oil and foldable capsular vitreous body tamponade.

Silicone oil has been the only long-term vitreous substitute used in the treatment of retinal detachment since 1962 by Cibis. Nevertheless, its effects on retinal vascular morphology and oxygen supply to the retina are ambiguous in current research. We previously invented a foldable capsular vitreous body (FCVB) to use as a new vitreous substitute in the treatment of severe retinal detachment, but its effects on the retinal vessel were unknown. Therefore, in this study, a standard three-port pars plana vitrectomy (PPV) was performed on the right eye of each rabbit and then silicone oil and FCVB were injected into the vitreous cavity as vitreous substitutes. After 180 days of retention, the retinal vascular morphology did not display any distinct abnormalities, and hypoxia-induced factor-1alpha (HIF-1α) and vascular endothelial growth factor (VEGF) did not vary markedly during the observation period in silicone oil tamponade- and FCVB-implanted eyes. This study may suggest that silicone oil and FCVB tamponade in rabbit eyes did not cause retinal vascular pathologic changes or retinal hypoxia for 180 days.

Functional evaluation of a novel vitreous substitute using polyethylene glycol sols injected into a foldable capsular vitreous body

Polyethylene glycol (PEG) is a short-term (41 days) potential vitreous substitute and is too short for an ideal vitreous substitute. Previously, a foldable capsular vitreous body (FCVB) was designed to mimic vitreous function. The aim of this study is to evaluate whether PEG injected into FCVB can serve as a long-term vitreous substitute. In vitro study, a concentration of 5% (w/v) PEG sols showed natural-like mechanical and optical properties in terms of pH, density, light transmittance, refractive index, interfacial tension, viscosity, rheology, and cytotoxicity. Then in vivo tests, 30 rabbits received standard pars plana vitrectomy, of which 12 eyes were implanted with PEG injected into FCVB, nine eyes were injected with PEG sols alone, and nine others were injected with balance salt solution as control. A clinical evaluation of the anterior segment, fundus, and intraocular pressure was measured pre- and postoperatively up to 180 days, which showed that FCVBs had good retina supporting function, except for a higher incidence of cataracts. Gross pathology, hematoxylin and eosin, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining analysis also showed that FCVBs had good biocompatibility, and that all quadrants of the capsular wall fitted well with the retina. This study demonstrated that PEG injected into FCVB can serve as a long-term vitreous substitute and has potential clinical use.