Separating the multi dots of retinal active bleeding with discovisc from infusion solution to rapidly restore visibility in severe proliferative diabetic retinopathy surgery

Separating the multi dots of retinal active bleeding with discovisc from infusion solution to rapidly restore visibility in severe proliferative diabetic retinopathy surgery | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Separating the multi dots of retinal active bleeding with discovisc from infusion solution to rapidly restore visibility in severe proliferative diabetic retinopathy surgery Yajun Liu, Yinong Guo, Yilinuer Yilihaer, Suyu Liu, Yanbo Bao, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7725292/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose To introduce a novel technique for restoring the refractive media transparency in severe proliferative diabetic retinopathy (PDR) surgery by injecting dispersive ophthalmic viscoelastic device (OVD; DisCoVisc) onto the retinal surface to separate the multi dots of active bleeding from infusion solution. Methods DisCoVisc was injected onto the retinal surface to control retinal bleeding diffusion in 12 eyes of 11 patients with severe PDR. The main outcome measures were intraoperative and postoperative vitreous hemorrhage complications. Follow-ups were performed at 1 day, and the last follow-up (ranging from 1 to 6 months) after surgery. Intraocular pressure (IOP) and best-corrected visual acuity (BCVA) measurements were performed preoperatively and at last follow-up postoperatively. Results Vitrectomy was completed successfully in all 12 eyes (12/12) without uncontrolled retinal bleeding diffusion intraoperative. Postoperative IOP increased compared with preoperative values ( t=-4.710, P = 0.001), but it could be controlled by topic ophthalmic medication. Postoperative BCVA was significantly improved compared with preoperative values (t = 5.149, P = 0.000). No other significant complications were observed. Conclusion This surgical technique can effectively and rapidly restore the refractive media transparency in severe PDR surgery, ensuring the smooth progression of the operation. Proliferative diabetic retinopathy Vitrectomy Ophthalmic viscoelastic device Fibrovascular membrane Refractive media Figures Figure 1 Figure 2 Figure 3 Introduction Minimally invasive pars plana vitrectomy (PPV) has been widely adopted for the surgical treatment of severe proliferative diabetic retinopathy (PDR). When there are non-resolving vitreous hemorrhages, extensive fibrovascular membranes, and tractional retinal detachment, vitrectomy is necessary [ 1 ] . Complete vitreous cortex removal and thorough fibrovascular membrane peeling, along with effective panretinal photocoagulation, are essential. The massive bleeding from neovascular membranes during their removal can severely impede surgical progress and may even lead to surgical failure. Although preoperative anti-vascular endothelial growth factor (VEGF) therapy can reduce the risk of intraoperative retinal hemorrhage to some extent [ 2 ] , bleeding is not still uncommon during surgery. Intraocular electrocoagulation can be used for distinct bleeding points. For multiple bleeding sites, methods such as increasing infusion pressure or injecting perfluorocarbon liquid into the vitreous cavity can be attempted to achieve hemostasis [ 3 ] ; however, these methods are not always effective. Additionally, excessively increasing infusion pressure during surgery can exacerbate retinal ischemia in patients with diabetic retinopathy, severely impacting postoperative visual function recovery [ 4 ] . DisCoVisc, composed of a mixture of sodium hyaluronate and chondroitin sulfate, adheres firmly to tissue surfaces and is commonly used to protect the corneal endothelium during phacoemulsification in cataract surgery [ 5 ] . We have also found in another study that DisCoVisc can firmly attach to the retinal surface and stabilize an inverted internal limiting membrane flap without being washed away by the infusion solution [ 6 ] . Studies have shown that sodium hyaluronate also has some procoagulant effects [ 7 ] . Therefore, utilizing the strong adhesive properties of DisCoVisc, we designed a method to inject DisCoVisc onto the retinal surface to cover multiple active bleeding dots, separating them from the clear infusion solution and rapidly restoring the transparency of the refractive media. This effectively prevents the obscuration of the surgical field due to massive bleeding during fibrovascular membrane peeling. Patients and methods Patients Perspective case series study. This study includes a series of cases involving patients with PDR, all diagnosed at Nanjing Drum Tower Hospital, the Affiliated Hospital of Medical School, Nanjing University. The surgeries were performed by the same surgeon (ZGX), who is experienced in vitreoretinal operations. All patients received an intravitreal injection of either conbercept or ranibizumab 3 to 5 days before surgery. They were all informed about the surgical procedure and associated risks and provided written informed consent. From February of 2024 to September of 2024, 11 cases involving 12 eyes were included in the study. Surgical Procedures A standard three-port pars plana vitrectomy (Constellation, Alcon, Fort Worth, TX) was performed. Cannulas were placed at the 2:00, 4:00/8:00, and 10:00 positions, with the infusion cannula positioned inferotemporally at 4:00/8:00. Using a wide-angle viewing system (RESIGHT, Carl Zeiss, Jena, Germany), the central axis and posterior hematic vitreous were removed. For fibrovascular membranes with relatively weak adhesions, use the vitrectomy cutter to aspirate, separate and cut. Alternate between aspiration, traction, and cutting techniques to completely clear the membranes. In cases of clearly identified bleeding points distant from major retinal vessels, endodiathermy was applied for hemostasis. If endodiathermy was not feasible, the infusion pressure could be increased to 40–60 mmHg, and if bleeding stopped after a few minutes, the surgery would continue. If bleeding persisted, and the intravitreal infusion solution became turbid due to bleeding, our designed method was employed, and the case was included in this study. Our method involved first performing a fluid-air exchange using the vitrectomy cutter (air pressure at 35 mmHg), followed by using a flute needle to aspirate as much intravitreal infusion solution as possible. A suitable amount of dispersive viscoelastic agent (DisCoVisc, Alcon Laboratories, Fort Worth, TX, USA) was injected into the vitreous cavity, covering the entire hemorrhagic area and a portion of the retina. After allowing the viscoelastic to settle for 10–15 seconds, the infusion was gradually reopened to allow the infusion solution to fill the vitreous cavity above the viscoelastic agent, then maintained continuous infusion. At this point, the intravitreal infusion solution became clear. The procedure continued with the removal of the peripheral and basal vitreous and retinal laser photocoagulation. Finally, the vitrectomy cutter was used to cut and clear the hemorrhage and fibrovascular membranes covered by the viscoelastic agent. If active bleeding was observed, endodiathermy was applied for hemostasis (refer to Figs. 1 and 2 ) (refer to Video 1). If blood clots and fibrovascular membranes were not completely removed but the viscoelastic had been fully cleared and the vitreous cavity fluid became hematic and opaque again, a repeat fluid-air exchange and re-injection of viscoelastic agent were performed to thoroughly clear the fibrovascular membranes and clots. Statistical analysis Statistical analyses were conducted using SPSS software version 23.0. Quantitative data are presented as mean ± standard deviation, and preoperative and postoperative best corrected visual acuity (BCVA) and intraocular pressure (IOP) were analyzed using paired t-tests. A P -value of less than 0.05 was considered statistically significant. Results From February 29, 2024 to September 12, 2024, a total of 136 surgeries for PDR were performed, of which 11 cases (12 eyes) employed this method. There were 9 cases for the right eye and 3 cases for the left eye. Male patients accounted for 9 cases (10 eyes) and female patients 2 cases (2 eyes). The average age was 45.25 ± 11.39 years (range, 33–62 years). The average preoperative IOP was 14.87 ± 1.99 mmHg (range, 13.00-18.50 mmHg), and the logMAR BCVA was 2.27 ± 0.95 (range, 1.00-3.47). During the surgery, viscoelastic agent was injected 1 to 3 times, averaging 1.33 ± 0.65 times, with an injection volume of 0.32 ± 0.08 ml. On the first postoperative day, the IOP was 25.6 ± 8.05 mmHg; compared to preoperative values, P <0.05, and postoperative vitreous rebleeding occurred in 1 eye. The follow-up period was 3.54 ± 2.37 months on average. At the last follow-up, the logMAR BCVA was 0.82 ± 0.36 (Fig. 3 ; Table 1 ). Table 1 Patients’ demographic data. Case Gender(F/M) /Age(years) /Eye(R/L) Pre-op anti-VEGF (Y/N) BCVA (t = 5.149, P = 0.000) IOP (t=-4.710, P = 0.001) Times of OVD injection Volume of total OVD (ml) Tamponade Post-op vitreous rebleeding (Y/N) Follow-up (months) Pre-op Last visit Pre-op 1d Post-op 1 M/53/R Y 0.01 0.4 15.0 30.6 1 0.3 SO N 6 2 M/35/R Y 0.02 0.4 16.0 19.2 1 0.4 SO N 5 3 M/33/R Y HM/20cm 0.15 13.0 16.2 1 0.3 SO N 6 4 M/36/R Y HM/10cm 0.1 17.1 23.7 1 0.3 SO N 4 5 M/36/L Y CF/30cm 0.02 16.3 47.4 2 0.4 SO Y 4 6 M/53/R Y 0.05 0.25 18.5 24.1 1 0.1 SO N 3 7 F/35/R Y 0.02 0.12 16.0 19.2 1 0.3 BSS N 1 8 M/53/L Y 0.04 0.1 14.0 25.7 2 0.4 SO N 2.5 9 M/55/R Y 0.1 0.15 13.0 21.2 1 0.3 SO N 1 10 M/62/R Y 0.01 0.25 14.0 28.9 1 0.3 SO N 1 11 F/59/L Y HM/20cm 0.30 14.0 27.3 1 0.3 SO N 8 12 M/33/R Y HM/20cm 0.1 11.5 23.7 3 0.4 AIR N 1 Note: F, female; M, male; R, right; L, left; BCVA, best-corrected visual acuity; VEGF, vascular endothelial growth factor; Pre-op, preoperation; Post-op, postoperation; IOP, intraocular pressure; OVD, ophthalmic viscoelastic device; SO, silicone oil; BSS, balanced salt solution;Y, yes; N, no; Discussion Complete removal of fibrovascular membranes is a critical step in the surgical management of PDR, yet intraoperative bleeding is a significant impediment during the peeling process. To reduce bleeding during the removal of neovascular membranes, many scholars administer intravitreal injections of anti-VEGF agents, such as ranibizumab, aflibercept, conbercept, and avastin, 3–5 days before surgery [ 8 , 9 ] . These treatments cause the neovascular vessels to contract and occlude, thus reducing intraoperative bleeding and facilitating the complete removal of fibrovascular membranes. Despite these measures, bleeding can still occur, leading to hemorrhagic opacity of intravitreal infusion solution, especially when non-valved cannulas are used. This situation severely compromises the clarity of the surgical field and can impede the progress of the surgery or even failure of surgery. Some scholars have also attempted to peel fibrovascular membranes under air in cases of PDR [ 10 ] , but this technique can be challenging for less experienced surgeons, especially when refractive media become opaque (due to corneal edema or lens opacity), making it difficult to maintain a clear surgical field. We designed a method involving the injection of DisCoVisc onto the retinal surface to cover active bleeding dots and rapidly restore the transparency of the refractive media. This procedure begins with a fluid-air exchange, aiming to completely aspirate the infusion solution, allowing the viscoelastic agent to make full contact with the retina and blood clots, thereby adhering to their surfaces, followed by the reintroduction of infusion solution. This restores the transparency of the vitreous cavity, allowing for the completion of peripheral and basal vitreous removal and retinal laser photocoagulation, and subsequently, the posterior pole procedures can be performed. Commonly used ophthalmic viscoelastic devices (OVD) are classified into two major categories: cohesive viscoelastic agents with higher viscosity and dispersive viscoelastic agents with medium-to-low viscosity. Cohesive viscoelastic agents typically have longer molecular chains and higher molecular weights (greater than 1000 kDa), with sodium hyaluronate at varying concentrations being a representative example. These agents possess high static viscosity, effectively maintaining the anterior chamber during cataract surgery, and are easily cleared under the influence of negative pressure and fluid flow. Conversely, dispersive viscoelastic agents, exemplified by chondroitin sulfate and hydroxypropyl methylcellulose, have shorter molecular chains and lower molecular weights (less than 1000 kDa), resulting in lower static viscosity. They are commonly used for corneal endothelial protection during cataract surgery due to their resistance to being cleared during surgery. DisCoVisc is a novel single-formulation viscoelastic that combines the benefits of both cohesive and dispersive viscoelastics, composed of 1.6% sodium hyaluronate and 4% chondroitin sulfate. With a relatively high molecular weight (1700 kDa), it possesses the static viscosity characteristic of cohesive viscoelastic agents, while also displaying a moderate cohesion-dispersion index (CDI) value (CDI = 12), allowing it to exhibit dispersive properties [ 11 , 12 ] . Differing from cohesive viscoelastic agents like sodium hyaluronate, DisCoVisc adheres firmly to the surfaces of intraocular tissues and is not easily flushed away by infusion solution flow. It is commonly used for protecting corneal endothelium during cataract surgeries. We innovatively applied DisCoVisc in cases of refractory diffuse bleeding during surgical treatment of PDR. Due to the complete adherence of the viscoelastic agent to blood clots and the retinal surface, even if bleeding occurs, the blood is confined under the viscoelastic agent, preventing it from entering the infusion solution and causing opacity that could impair surgical field visibility. Some studies have also found that sodium hyaluronate has certain procoagulant properties [ 7 ] . Therefore, the injected viscoelastic agent not only promotes clotting but also restricts bleeding. During the removal of blood clots and fibrovascular membranes, a portion of the viscoelastic agent is also aspirated, but this does not result in cavity formation due to the agent's collapse. The viscoelastic agent is highly compatible with intraocular tissues, and thus, residual agent postoperatively does not cause any toxic side effects to ocular tissues [ 5 ] . In our cases of 12 eyes, an intravitreal injection of 0.5 mg of conbercept or ranibizumab 3–5 days was administered before surgery, yet uncontrollable multifocal bleeding still occurred intraoperatively. Fortunately, the technique of injecting DisCoVisc onto the retinal surface to cover multiple active bleeding dots rapidly restored the transparency of the refractive media in 12 treated eyes, preventing surgery cancellations due to opaque infusion solution. This improved surgical efficiency, reduced operative time, and significantly improved postoperative vision. In this study, the postoperative IOP was significantly higher than preoperatively, which we speculate may be related to silicone oil filling [ 13 ] . This is because DisCoVisc was largely removed during surgery, leaving only a very small amount adhering to the retinal surface. In another of our studies, the amount of retained DisCoVisc at the end of surgery (0.2–0.3 ml) was much larger than in this study, yet the postoperative IOP did not significantly increase [ 6 ] . We believe this method has several advantages: 1. Compared to perfluorocarbon liquid, DisCoVisc is more cost-effective and does not significantly increase the medical expenses for patients; 2. The procedure is simple and quick, requiring just a fluid-air exchange before viscoelastic agent injection; 3. The viscoelastic agent adheres to the hemorrhage and retinal surface in just about 10–15 seconds, not significantly prolonging the surgery; 4. Sodium hyaluronate not only confines retinal bleeding but also promotes clotting; 5. Sodium hyaluronate and chondroitin sulfate are non-toxic and highly compatible with intraocular tissues, ensuring no toxic damage to retinal tissues even if residual amounts are left. In summary, the method of injecting DisCoVisc onto the retinal surface to cover multipleactive bleeding dots can be an effective strategy for confining retinal hemorrhage to restore the transparent refractive media and promoting clotting during fibrovascular membrane peeling in surgeries for PDR, ensuring the smooth progression of the operation. However, this study is a single-center case series with a small sample size, and further validation with larger-scale studies is needed in the future. In conclusion, we present a novel technique for rapid restoring the refractive media transparency in severe proliferative diabetic retinopathy surgery by injecting dispersive ophthalmic viscoelastic device (DisCoVisc) onto the retinal surface to separate the multi dots active bleeding from infusion solution, ensuring the smooth progression of the operation. Abbreviations PDR Proliferative diabetic retinopathy OVD Ophthalmic viscoelastic device IOP Intraocular pressure, BCVA Best-corrected visual acuity PPV Pars plana vitrectomy VEGF Vascular endothelial growth factor CDI Cohesion-dispersion index Declarations Acknowledgements Not applicable. Author contributions Zhenggao Xie was responsible for the conception and design of this study. Yajun Liu and Yanbo Bao were acquired the data and analyzed and interpreted the data. Yinong Guo was the major contributor in writing the manuscript. Yilinuer Yilihaer was revised the manuscript critically. All authors have read and approved the final submitted version of the manuscript. Funding The author(s) reported that there is no funding associated with the work featured in this article. Availability of data and materials No datasets were generated or analysed during the current study. Ethics approval and consent to participate This study was approved by the Ethics Committee of Nanjing Drum Tower Hospital. All participants provided written informed consent to participate in the study. The research was conducted in accordance with the principles of the Declaration of Helsinki, and all relevant guidelines and regulations were followed. Clinical trial number: not applicable. Competing interests The authors declare no competing interests. References Castillo J, Aleman I, Rush SW, Rush RB. Preoperative bevacizumab administration in proliferative diabetic retinopathy patients undergoing vitrectomy: a randomized and controlled trial comparing interval variation. Am J Ophthalmol. 2017;183:1-10. https:// doi. org/10.1016/j.ajo.2017.08.013. Zhao X, Xia S, Chen Y. Antivascular endothelial growth factor agents pretreatment before vitrectomy for complicated proliferative diabetic retinopathy: a meta-analysis of randomised controlled trials. Br J Ophthalmol. 2018;102:1077-1085. https:// doi. org/10.1136/bjophthalmol-2017-311344. Imamura Y, Minami M, Ueki M, Satoh B, Ikeda T. Use of perfluorocarbon liquid during vitrectomy for severe proliferative diabetic retinopathy. Br J Ophthalmol. 2003;87:563-566. https:// doi. org/10.1136/bjo.87.5.563. Gass JD. Outer retinal ischemic infarction: a newly recognized complication of cataract extraction and closed vitrectomy. Trans New Orleans Acad Ophthalmol. 1983;31:223-227. Modi S S, Davison JA, Walters T. Safety, efficacy, and intraoperative characteristics of DisCoVisc and Healon ophthalmic viscosurgical devices for cataract surgery. Clin Ophthalmol. 2011;5:1381-1389.https:// doi. org/10.2147/OPTH.S22243. Liu Y, Jiang F, Chen F, et al. Minimal posterior pole vitrectomy and fixing the inverted internal limiting membrane flap with DisCoVisc for macular hole: no gas or air tamponade. Retina. 2023;43:2208-2214. https:// doi. org/10.1097/IAE.0000000000003919. Packer AJ, Mccuen BN, Hutton WL, Ramsay RC. Procoagulant effects of intraocular sodium hyaluronate (Healon) after phakic diabetic vitrectomy. A prospective, randomized study. Ophthalmology. 1989;96:1491-1494. https:// doi. org/10.1016/s0161-6420(89)32686-8. Li S, Guo L, Zhou P, et al. Comparison of efficacy and safety of intravitreal ranibizumab and conbercept before vitrectomy in Chinese proliferative diabetic retinopathy patients: a prospective randomized controlled trial. Eye Vis (Lond). 2022;9:44.https:// doi. org/10.1186/s40662-022-00316-z. Chen HJ, Wang CG, Dou HL, Feng XF, Xu YM, Ma ZZ. Effect of intravitreal ranibizumab pretreatment on vitrectomy in young patients with proliferative diabetic retinopathy. Ann Palliat Med. 2020;9:82-89. https:// doi. org/ 10.21037/apm.2020.01.10. Kim YJ, Seo H, Lee DY, Nam DH. Air-Perfused 23-Gauge sutureless diabetic vitrectomy for control of intraoperative bleeding during removal of fibrovascular membrane. Curr Eye Res. 2019;44:334-340. https:// doi. org/10.1080/02713683.2018.1536214. Arshinoff SA. Dispersive-cohesive viscoelastic soft shell technique. J Cataract Refract Surg. 1999;25:167-173. https:// doi. org/10.1080/02713683.2018. Arshinoff SA, Jafari M. New classification of ophthalmic viscosurgical devices--2005. J Cataract Refract Surg. 2005;31:2167-2171. https:// doi. org/10.1016/j.jcrs.2005.08.056. Antoun J, Azar G, Jabbour E, et al. Vitreoretinal surgery with silicone oil tamponade in primary uncomplicated rhegmatogenous retinal detachment: Clinical Outcomes and Complications. Retina. 2016;36:1906-1912. https:// doi. org/10.1097/IAE.0000000000001008. Additional Declarations No competing interests reported. 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02:45:07","extension":"png","order_by":11,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":1269435,"visible":true,"origin":"","legend":"","description":"","filename":"OnlineFigure1.png","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/f6730915f14f5a73f6d9b295.png"},{"id":93543817,"identity":"0a399cc1-03f3-412a-998d-9791d4e4dbd4","added_by":"auto","created_at":"2025-10-15 02:45:07","extension":"png","order_by":12,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":259531,"visible":true,"origin":"","legend":"","description":"","filename":"OnlineFigure2.png","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/bcf8e36b0b8e6ed3b8e4c76b.png"},{"id":93543814,"identity":"bd3cb29f-b99e-4685-8fdf-458d3ed1ca6c","added_by":"auto","created_at":"2025-10-15 02:45:07","extension":"png","order_by":13,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":75245,"visible":true,"origin":"","legend":"","description":"","filename":"OnlineFigure3.png","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/e182aa554c8703eff821da50.png"},{"id":93543815,"identity":"93db070f-b3f5-49f6-a5a6-d507d7e77a9d","added_by":"auto","created_at":"2025-10-15 02:45:07","extension":"xml","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":61884,"visible":true,"origin":"","legend":"","description":"","filename":"f7ff2ce43fb54668a937dd3a08caf41c1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/0408bd5dc66fa2222ddf482e.xml"},{"id":93543820,"identity":"4e6e867d-cf06-4481-82e1-6c5ec2f35fec","added_by":"auto","created_at":"2025-10-15 02:45:08","extension":"html","order_by":15,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":68065,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/af4a6bb43c4d133a2d80284d.html"},{"id":93543806,"identity":"2be1f7eb-2642-4462-9d24-79ce348b4f71","added_by":"auto","created_at":"2025-10-15 02:45:07","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":1898061,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePhotographs of surgical process for PDR with DisCoVisc.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA: Using the vitrectomy cutter to aspirate the vitreous cavity infusion solution for a fluid-air exchange. B: Injecting a suitable amount of DisCoVisc® into the vitreous cavity to cover blood clots and fibrovascular membranes. C: The procedure with the removal of the peripheral and basal vitreous. D: The procedure with retinal laser photocoagulation. E: Using the vitrectomy cutter to gradually remove the blood clots and fibrovascular membranes. F: Clearing all fibrovascular membranes.\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/3500258038918af286c6cfa3.jpg"},{"id":93543807,"identity":"a7675843-fcff-4201-83c4-156d73d25134","added_by":"auto","created_at":"2025-10-15 02:45:07","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":768476,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDiagrams of surgical process for PDR with DisCoVisc\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA: The intravitreal infusion solution became opaque due to bleeding. B: Fluid-air exchange to remove blood in the vitreous cavity. C: The bleeding dots surface is injected with DisCoVisc to limit the bleeding diffusion. D: The infusion was gradually reopened，and the intravitreal infusion solution became clear. E: The procedure with the removal of the peripheral and basal vitreous. F: Using the vitrectomy cutter to remove the blood clots and DisCoVisc.\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/6aaf1670d679dc01bee789f9.jpg"},{"id":93543808,"identity":"fa4513d1-3171-467d-975f-491b56d58096","added_by":"auto","created_at":"2025-10-15 02:45:07","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":228663,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eChanges in BCVA and IOP before and after surgery\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eA. BCVA changes before and after surgery. B. IOP changes before and after surgery. **P＜0.05.\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/a3fc5593ac6d9b6bea501ef4.jpg"},{"id":96708386,"identity":"1bf49ab9-c5f4-442a-b2ec-6514b4c25d58","added_by":"auto","created_at":"2025-11-25 10:01:36","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3575026,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/63bfacec-482d-4be1-a370-6b3ed4e1b07b.pdf"},{"id":93543824,"identity":"414046f9-66fd-4133-8cbe-ee056e71cad5","added_by":"auto","created_at":"2025-10-15 02:45:08","extension":"mp4","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":26595699,"visible":true,"origin":"","legend":"","description":"","filename":"DisCoVisccoverbleedingpointstorestorationoftransparency.mp4","url":"https://assets-eu.researchsquare.com/files/rs-7725292/v1/d57fdcbd57c7323c2b798d5d.mp4"}],"financialInterests":"No competing interests reported.","formattedTitle":"Separating the multi dots of retinal active bleeding with discovisc from infusion solution to rapidly restore visibility in severe proliferative diabetic retinopathy surgery","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMinimally invasive pars plana vitrectomy (PPV) has been widely adopted for the surgical treatment of severe proliferative diabetic retinopathy (PDR). When there are non-resolving vitreous hemorrhages, extensive fibrovascular membranes, and tractional retinal detachment, vitrectomy is necessary\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Complete vitreous cortex removal and thorough fibrovascular membrane peeling, along with effective panretinal photocoagulation, are essential. The massive bleeding from neovascular membranes during their removal can severely impede surgical progress and may even lead to surgical failure. Although preoperative anti-vascular endothelial growth factor (VEGF) therapy can reduce the risk of intraoperative retinal hemorrhage to some extent\u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e, bleeding is not still uncommon during surgery. Intraocular electrocoagulation can be used for distinct bleeding points. For multiple bleeding sites, methods such as increasing infusion pressure or injecting perfluorocarbon liquid into the vitreous cavity can be attempted to achieve hemostasis\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e; however, these methods are not always effective. Additionally, excessively increasing infusion pressure during surgery can exacerbate retinal ischemia in patients with diabetic retinopathy, severely impacting postoperative visual function recovery\u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. DisCoVisc, composed of a mixture of sodium hyaluronate and chondroitin sulfate, adheres firmly to tissue surfaces and is commonly used to protect the corneal endothelium during phacoemulsification in cataract surgery\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. We have also found in another study that DisCoVisc can firmly attach to the retinal surface and stabilize an inverted internal limiting membrane flap without being washed away by the infusion solution\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e. Studies have shown that sodium hyaluronate also has some procoagulant effects\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. Therefore, utilizing the strong adhesive properties of DisCoVisc, we designed a method to inject DisCoVisc onto the retinal surface to cover multiple active bleeding dots, separating them from the clear infusion solution and rapidly restoring the transparency of the refractive media. This effectively prevents the obscuration of the surgical field due to massive bleeding during fibrovascular membrane peeling.\u003c/p\u003e"},{"header":"Patients and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003ePatients\u003c/h2\u003e\u003cp\u003ePerspective case series study. This study includes a series of cases involving patients with PDR, all diagnosed at Nanjing Drum Tower Hospital, the Affiliated Hospital of Medical School, Nanjing University. The surgeries were performed by the same surgeon (ZGX), who is experienced in vitreoretinal operations. All patients received an intravitreal injection of either conbercept or ranibizumab 3 to 5 days before surgery. They were all informed about the surgical procedure and associated risks and provided written informed consent. From February of 2024 to September of 2024, 11 cases involving 12 eyes were included in the study.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eSurgical Procedures\u003c/h3\u003e\n\u003cp\u003eA standard three-port pars plana vitrectomy (Constellation, Alcon, Fort Worth, TX) was performed. Cannulas were placed at the 2:00, 4:00/8:00, and 10:00 positions, with the infusion cannula positioned inferotemporally at 4:00/8:00. Using a wide-angle viewing system (RESIGHT, Carl Zeiss, Jena, Germany), the central axis and posterior hematic vitreous were removed. For fibrovascular membranes with relatively weak adhesions, use the vitrectomy cutter to aspirate, separate and cut. Alternate between aspiration, traction, and cutting techniques to completely clear the membranes. In cases of clearly identified bleeding points distant from major retinal vessels, endodiathermy was applied for hemostasis. If endodiathermy was not feasible, the infusion pressure could be increased to 40\u0026ndash;60 mmHg, and if bleeding stopped after a few minutes, the surgery would continue. If bleeding persisted, and the intravitreal infusion solution became turbid due to bleeding, our designed method was employed, and the case was included in this study. Our method involved first performing a fluid-air exchange using the vitrectomy cutter (air pressure at 35 mmHg), followed by using a flute needle to aspirate as much intravitreal infusion solution as possible. A suitable amount of dispersive viscoelastic agent (DisCoVisc, Alcon Laboratories, Fort Worth, TX, USA) was injected into the vitreous cavity, covering the entire hemorrhagic area and a portion of the retina. After allowing the viscoelastic to settle for 10\u0026ndash;15 seconds, the infusion was gradually reopened to allow the infusion solution to fill the vitreous cavity above the viscoelastic agent, then maintained continuous infusion. At this point, the intravitreal infusion solution became clear. The procedure continued with the removal of the peripheral and basal vitreous and retinal laser photocoagulation. Finally, the vitrectomy cutter was used to cut and clear the hemorrhage and fibrovascular membranes covered by the viscoelastic agent. If active bleeding was observed, endodiathermy was applied for hemostasis (refer to Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) (refer to Video 1). If blood clots and fibrovascular membranes were not completely removed but the viscoelastic had been fully cleared and the vitreous cavity fluid became hematic and opaque again, a repeat fluid-air exchange and re-injection of viscoelastic agent were performed to thoroughly clear the fibrovascular membranes and clots.\u003c/p\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analysis\u003c/h2\u003e\u003cp\u003eStatistical analyses were conducted using SPSS software version 23.0. Quantitative data are presented as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation, and preoperative and postoperative best corrected visual acuity (BCVA) and intraocular pressure (IOP) were analyzed using paired t-tests. A \u003cem\u003eP\u003c/em\u003e-value of less than 0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003eFrom February 29, 2024 to September 12, 2024, a total of 136 surgeries for PDR were performed, of which 11 cases (12 eyes) employed this method. There were 9 cases for the right eye and 3 cases for the left eye. Male patients accounted for 9 cases (10 eyes) and female patients 2 cases (2 eyes). The average age was 45.25\u0026thinsp;\u0026plusmn;\u0026thinsp;11.39 years (range, 33\u0026ndash;62 years). The average preoperative IOP was 14.87\u0026thinsp;\u0026plusmn;\u0026thinsp;1.99 mmHg (range, 13.00-18.50 mmHg), and the logMAR BCVA was 2.27\u0026thinsp;\u0026plusmn;\u0026thinsp;0.95 (range, 1.00-3.47). During the surgery, viscoelastic agent was injected 1 to 3 times, averaging 1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.65 times, with an injection volume of 0.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08 ml. On the first postoperative day, the IOP was 25.6\u0026thinsp;\u0026plusmn;\u0026thinsp;8.05 mmHg; compared to preoperative values, \u003cem\u003eP\u003c/em\u003e\u0026lt;0.05, and postoperative vitreous rebleeding occurred in 1 eye. The follow-up period was 3.54\u0026thinsp;\u0026plusmn;\u0026thinsp;2.37 months on average. At the last follow-up, the logMAR BCVA was 0.82\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36 (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePatients\u0026rsquo; demographic data.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"12\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eCase\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eGender(F/M)\u003c/p\u003e\u003cp\u003e/Age(years)\u003c/p\u003e\u003cp\u003e/Eye(R/L)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePre-op\u003c/p\u003e\u003cp\u003eanti-VEGF\u003c/p\u003e\u003cp\u003e(Y/N)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003eBCVA\u003c/p\u003e\u003cp\u003e(t\u0026thinsp;=\u0026thinsp;5.149, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.000)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e\u003cp\u003eIOP\u003c/p\u003e\u003cp\u003e(t=-4.710, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eTimes of OVD injection\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eVolume of total OVD (ml)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eTamponade\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c11\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003ePost-op\u003c/p\u003e\u003cp\u003evitreous rebleeding\u003c/p\u003e\u003cp\u003e(Y/N)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c12\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eFollow-up\u003c/p\u003e\u003cp\u003e(months)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003ePre-op\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eLast visit\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003ePre-op\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1d Post-op\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/53/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e15.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e30.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/35/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e16.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e19.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/33/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHM/20cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e13.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e16.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/36/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHM/10cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e17.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e23.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/36/L\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eCF/30cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e16.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e47.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/53/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e18.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e24.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eF/35/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e16.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e19.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eBSS\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/53/L\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e14.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e25.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e2.5\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/55/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e13.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e21.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/62/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e14.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e28.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eF/59/L\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHM/20cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e14.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e27.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eSO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eM/33/R\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eY\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHM/20cm\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e11.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e23.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c9\"\u003e\u003cp\u003e0.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003eAIR\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c11\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c12\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"12\"\u003eNote: F, female; M, male; R, right; L, left; BCVA, best-corrected visual acuity; VEGF, vascular endothelial growth factor; Pre-op, preoperation; Post-op, postoperation; IOP, intraocular pressure; OVD, ophthalmic viscoelastic device; SO, silicone oil; BSS, balanced salt solution;Y, yes; N, no;\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eComplete removal of fibrovascular membranes is a critical step in the surgical management of PDR, yet intraoperative bleeding is a significant impediment during the peeling process. To reduce bleeding during the removal of neovascular membranes, many scholars administer intravitreal injections of anti-VEGF agents, such as ranibizumab, aflibercept, conbercept, and avastin, 3\u0026ndash;5 days before surgery\u003csup\u003e[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e. These treatments cause the neovascular vessels to contract and occlude, thus reducing intraoperative bleeding and facilitating the complete removal of fibrovascular membranes. Despite these measures, bleeding can still occur, leading to hemorrhagic opacity of intravitreal infusion solution, especially when non-valved cannulas are used. This situation severely compromises the clarity of the surgical field and can impede the progress of the surgery or even failure of surgery. Some scholars have also attempted to peel fibrovascular membranes under air in cases of PDR\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e, but this technique can be challenging for less experienced surgeons, especially when refractive media become opaque (due to corneal edema or lens opacity), making it difficult to maintain a clear surgical field. We designed a method involving the injection of DisCoVisc onto the retinal surface to cover active bleeding dots and rapidly restore the transparency of the refractive media. This procedure begins with a fluid-air exchange, aiming to completely aspirate the infusion solution, allowing the viscoelastic agent to make full contact with the retina and blood clots, thereby adhering to their surfaces, followed by the reintroduction of infusion solution. This restores the transparency of the vitreous cavity, allowing for the completion of peripheral and basal vitreous removal and retinal laser photocoagulation, and subsequently, the posterior pole procedures can be performed.\u003c/p\u003e\u003cp\u003eCommonly used ophthalmic viscoelastic devices (OVD) are classified into two major categories: cohesive viscoelastic agents with higher viscosity and dispersive viscoelastic agents with medium-to-low viscosity. Cohesive viscoelastic agents typically have longer molecular chains and higher molecular weights (greater than 1000 kDa), with sodium hyaluronate at varying concentrations being a representative example. These agents possess high static viscosity, effectively maintaining the anterior chamber during cataract surgery, and are easily cleared under the influence of negative pressure and fluid flow. Conversely, dispersive viscoelastic agents, exemplified by chondroitin sulfate and hydroxypropyl methylcellulose, have shorter molecular chains and lower molecular weights (less than 1000 kDa), resulting in lower static viscosity. They are commonly used for corneal endothelial protection during cataract surgery due to their resistance to being cleared during surgery. DisCoVisc is a novel single-formulation viscoelastic that combines the benefits of both cohesive and dispersive viscoelastics, composed of 1.6% sodium hyaluronate and 4% chondroitin sulfate. With a relatively high molecular weight (1700 kDa), it possesses the static viscosity characteristic of cohesive viscoelastic agents, while also displaying a moderate cohesion-dispersion index (CDI) value (CDI\u0026thinsp;=\u0026thinsp;12), allowing it to exhibit dispersive properties\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eDiffering from cohesive viscoelastic agents like sodium hyaluronate, DisCoVisc adheres firmly to the surfaces of intraocular tissues and is not easily flushed away by infusion solution flow. It is commonly used for protecting corneal endothelium during cataract surgeries. We innovatively applied DisCoVisc in cases of refractory diffuse bleeding during surgical treatment of PDR. Due to the complete adherence of the viscoelastic agent to blood clots and the retinal surface, even if bleeding occurs, the blood is confined under the viscoelastic agent, preventing it from entering the infusion solution and causing opacity that could impair surgical field visibility. Some studies have also found that sodium hyaluronate has certain procoagulant properties\u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. Therefore, the injected viscoelastic agent not only promotes clotting but also restricts bleeding. During the removal of blood clots and fibrovascular membranes, a portion of the viscoelastic agent is also aspirated, but this does not result in cavity formation due to the agent's collapse. The viscoelastic agent is highly compatible with intraocular tissues, and thus, residual agent postoperatively does not cause any toxic side effects to ocular tissues\u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. In our cases of 12 eyes, an intravitreal injection of 0.5 mg of conbercept or ranibizumab 3\u0026ndash;5 days was administered before surgery, yet uncontrollable multifocal bleeding still occurred intraoperatively. Fortunately, the technique of injecting DisCoVisc onto the retinal surface to cover multiple active bleeding dots rapidly restored the transparency of the refractive media in 12 treated eyes, preventing surgery cancellations due to opaque infusion solution. This improved surgical efficiency, reduced operative time, and significantly improved postoperative vision. In this study, the postoperative IOP was significantly higher than preoperatively, which we speculate may be related to silicone oil filling\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. This is because DisCoVisc was largely removed during surgery, leaving only a very small amount adhering to the retinal surface. In another of our studies, the amount of retained DisCoVisc at the end of surgery (0.2\u0026ndash;0.3 ml) was much larger than in this study, yet the postoperative IOP did not significantly increase\u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e. We believe this method has several advantages: 1. Compared to perfluorocarbon liquid, DisCoVisc is more cost-effective and does not significantly increase the medical expenses for patients; 2. The procedure is simple and quick, requiring just a fluid-air exchange before viscoelastic agent injection; 3. The viscoelastic agent adheres to the hemorrhage and retinal surface in just about 10\u0026ndash;15 seconds, not significantly prolonging the surgery; 4. Sodium hyaluronate not only confines retinal bleeding but also promotes clotting; 5. Sodium hyaluronate and chondroitin sulfate are non-toxic and highly compatible with intraocular tissues, ensuring no toxic damage to retinal tissues even if residual amounts are left.\u003c/p\u003e\u003cp\u003eIn summary, the method of injecting DisCoVisc onto the retinal surface to cover multipleactive bleeding dots can be an effective strategy for confining retinal hemorrhage to restore the transparent refractive media and promoting clotting during fibrovascular membrane peeling in surgeries for PDR, ensuring the smooth progression of the operation. However, this study is a single-center case series with a small sample size, and further validation with larger-scale studies is needed in the future.\u003c/p\u003e\u003cp\u003eIn conclusion, we present a novel technique for rapid restoring the refractive media transparency in severe proliferative diabetic retinopathy surgery by injecting dispersive ophthalmic viscoelastic device (DisCoVisc) onto the retinal surface to separate the multi dots active bleeding from infusion solution, ensuring the smooth progression of the operation.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003ePDR \u0026nbsp;Proliferative diabetic retinopathy\u003c/p\u003e\n\u003cp\u003eOVD \u0026nbsp;Ophthalmic viscoelastic device\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIOP \u0026nbsp;Intraocular pressure,\u003c/p\u003e\n\u003cp\u003eBCVA \u0026nbsp;Best-corrected visual acuity\u003c/p\u003e\n\u003cp\u003ePPV \u0026nbsp;Pars plana vitrectomy \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eVEGF \u0026nbsp;Vascular endothelial growth factor\u003c/p\u003e\n\u003cp\u003eCDI \u0026nbsp;Cohesion-dispersion index\u0026nbsp;\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eZhenggao Xie was responsible for the conception and design of this study. Yajun Liu and Yanbo Bao were acquired the data and analyzed and interpreted the data. Yinong Guo was the major contributor in writing the manuscript. Yilinuer Yilihaer was revised the manuscript critically. All authors have read and approved the final submitted version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author(s) reported that there is no funding associated with the work featured in this article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo datasets were generated or analysed during the current study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Nanjing Drum Tower \u0026nbsp;Hospital. All participants provided written informed consent to participate in the study. The research was conducted in accordance with the principles of the Declaration of Helsinki, and all relevant guidelines and regulations were followed. Clinical trial number: not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eCastillo J, Aleman I, Rush SW, Rush RB. Preoperative bevacizumab administration in proliferative diabetic retinopathy patients undergoing vitrectomy: a randomized and controlled trial comparing interval variation. Am J Ophthalmol. 2017;183:1-10. https:// doi. org/10.1016/j.ajo.2017.08.013.\u003c/li\u003e\n\u003cli\u003eZhao X, Xia S, Chen Y. Antivascular endothelial growth factor agents pretreatment before vitrectomy for complicated proliferative diabetic retinopathy: a meta-analysis of randomised controlled trials. Br J Ophthalmol. 2018;102:1077-1085. https:// doi. org/10.1136/bjophthalmol-2017-311344.\u003c/li\u003e\n\u003cli\u003eImamura Y, Minami M, Ueki M, Satoh B, Ikeda T. Use of perfluorocarbon liquid during vitrectomy for severe proliferative diabetic retinopathy. Br J Ophthalmol. 2003;87:563-566. https:// doi. org/10.1136/bjo.87.5.563.\u003c/li\u003e\n\u003cli\u003eGass JD. Outer retinal ischemic infarction: a newly recognized complication of cataract extraction and closed vitrectomy. Trans New Orleans Acad Ophthalmol. 1983;31:223-227.\u003c/li\u003e\n\u003cli\u003eModi S S, Davison JA, Walters T. Safety, efficacy, and intraoperative characteristics of DisCoVisc and Healon ophthalmic viscosurgical devices for cataract surgery. Clin Ophthalmol. 2011;5:1381-1389.https:// doi. org/10.2147/OPTH.S22243. \u003c/li\u003e\n\u003cli\u003eLiu Y, Jiang F, Chen F, et al. Minimal posterior pole vitrectomy and fixing the inverted internal limiting membrane flap with DisCoVisc for macular hole: no gas or air tamponade. Retina. 2023;43:2208-2214. https:// doi. org/10.1097/IAE.0000000000003919.\u003c/li\u003e\n\u003cli\u003ePacker AJ, Mccuen BN, Hutton WL, Ramsay RC. Procoagulant effects of intraocular sodium hyaluronate (Healon) after phakic diabetic vitrectomy. A prospective, randomized study. Ophthalmology. 1989;96:1491-1494. https:// doi. org/10.1016/s0161-6420(89)32686-8.\u003c/li\u003e\n\u003cli\u003eLi S, Guo L, Zhou P, et al. Comparison of efficacy and safety of intravitreal ranibizumab and conbercept before vitrectomy in Chinese proliferative diabetic retinopathy patients: a prospective randomized controlled trial. Eye Vis (Lond). 2022;9:44.https:// doi. org/10.1186/s40662-022-00316-z.\u003c/li\u003e\n\u003cli\u003eChen HJ, Wang CG, Dou HL, Feng XF, Xu YM, Ma ZZ. Effect of intravitreal ranibizumab pretreatment on vitrectomy in young patients with proliferative diabetic retinopathy. Ann Palliat Med. 2020;9:82-89. https:// doi. org/ 10.21037/apm.2020.01.10.\u003c/li\u003e\n\u003cli\u003eKim YJ, Seo H, Lee DY, Nam DH. Air-Perfused 23-Gauge sutureless diabetic vitrectomy for control of intraoperative bleeding during removal of fibrovascular membrane. Curr Eye Res. 2019;44:334-340. https:// doi. org/10.1080/02713683.2018.1536214. \u003c/li\u003e\n\u003cli\u003eArshinoff SA. Dispersive-cohesive viscoelastic soft shell technique. J Cataract Refract Surg. 1999;25:167-173. https:// doi. org/10.1080/02713683.2018.\u003c/li\u003e\n\u003cli\u003eArshinoff SA, Jafari M. New classification of ophthalmic viscosurgical devices--2005. J Cataract Refract Surg. 2005;31:2167-2171. https:// doi. org/10.1016/j.jcrs.2005.08.056.\u003c/li\u003e\n\u003cli\u003eAntoun J, Azar G, Jabbour E, et al. Vitreoretinal surgery with silicone oil tamponade in primary uncomplicated rhegmatogenous retinal detachment: Clinical Outcomes and Complications. Retina. 2016;36:1906-1912. https:// doi. org/10.1097/IAE.0000000000001008.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Proliferative diabetic retinopathy, Vitrectomy, Ophthalmic viscoelastic device, Fibrovascular membrane, Refractive media","lastPublishedDoi":"10.21203/rs.3.rs-7725292/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7725292/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003ePurpose\u003c/h2\u003e\u003cp\u003eTo introduce a novel technique for restoring the refractive media transparency in severe proliferative diabetic retinopathy (PDR) surgery by injecting dispersive ophthalmic viscoelastic device (OVD; DisCoVisc) onto the retinal surface to separate the multi dots of active bleeding from infusion solution.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eDisCoVisc was injected onto the retinal surface to control retinal bleeding diffusion in 12 eyes of 11 patients with severe PDR. The main outcome measures were intraoperative and postoperative vitreous hemorrhage complications. Follow-ups were performed at 1 day, and the last follow-up (ranging from 1 to 6 months) after surgery. Intraocular pressure (IOP) and best-corrected visual acuity (BCVA) measurements were performed preoperatively and at last follow-up postoperatively.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eVitrectomy was completed successfully in all 12 eyes (12/12) without uncontrolled retinal bleeding diffusion intraoperative. Postoperative IOP increased compared with preoperative values ( t=-4.710, P\u0026thinsp;=\u0026thinsp;0.001), but it could be controlled by topic ophthalmic medication. Postoperative BCVA was significantly improved compared with preoperative values (t\u0026thinsp;=\u0026thinsp;5.149, P\u0026thinsp;=\u0026thinsp;0.000). No other significant complications were observed.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eThis surgical technique can effectively and rapidly restore the refractive media transparency in severe PDR surgery, ensuring the smooth progression of the operation.\u003c/p\u003e","manuscriptTitle":"Separating the multi dots of retinal active bleeding with discovisc from infusion solution to rapidly restore visibility in severe proliferative diabetic retinopathy surgery","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-15 02:45:02","doi":"10.21203/rs.3.rs-7725292/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4a343f3b-dedb-411d-b21d-568642b836ac","owner":[],"postedDate":"October 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-11-22T08:38:42+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-15 02:45:02","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7725292","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7725292","identity":"rs-7725292","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}