Preoperative Anti-VEGF and the Cumulative Risk of Post-operative Vitreous Hemorrhage in PDR: A 2-Year Survival Analysis and Evaluation of Surgical Burden

Preoperative Anti-VEGF and the Cumulative Risk of Post-operative Vitreous Hemorrhage in PDR: A 2-Year Survival Analysis and Evaluation of Surgical Burden | 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 Preoperative Anti-VEGF and the Cumulative Risk of Post-operative Vitreous Hemorrhage in PDR: A 2-Year Survival Analysis and Evaluation of Surgical Burden Yuxian Lin, Ruibin Wu, Gengjia Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9117069/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Purpose To investigate the long-term risk factors for post-operative vitreous hemorrhage (VH) within 24 months following vitrectomy for proliferative diabetic retinopathy (PDR), evaluate the protective efficacy of preoperative anti-VEGF therapy, and quantify the associated secondary surgical burden. Methods This retrospective cohort study included 735 eyes from 735 PDR patients. A 24-month survival analysis was employed to categorize patients into VH (n = 179) and non-VH (n = 556) groups. Independent predictors were identified using univariate and multivariate Cox proportional hazards models. A sensitivity analysis was performed on a "pure hemorrhage model" (n = 676) by excluding eyes with post-operative tractional retinal detachment (TRD) to isolate the direct vascular-stabilizing effect of anti-VEGF. Results The overall cumulative incidence of post-operative VH was 18.4% at 12 months and 25.7% at 24 months. Multivariate Cox analysis revealed that preoperative anti-VEGF injection was the most potent protective factor, associated with a 63% reduction in VH hazard (HR 0.37; 95% CI, 0.27–0.51; P < 0.001). This protective effect remained robust in the sensitivity analysis (HR 0.32; P < 0.001), indicating a direct vascular stabilization independent of anatomical success. Independent risk factors included severe fibrovascular traction (HR 1.93; P = 0.003), younger age, higher HbA1c, and elevated serum creatinine (all P < 0.05). Patients in the VH group had significantly poorer final visual outcomes (1.33 ± 0.75 vs. 0.92 ± 0.60 LogMAR; P < 0.001) and a markedly higher reoperation rate (31.3% vs. 7.2%). Notably, hemorrhage-related indications accounted for 58.4% of the total secondary surgical workload. Conclusion Post-operative VH is a dominant driver of long-term visual impairment and secondary surgical burden in PDR. Preoperative anti-VEGF confers a direct, sustained protective effect by stabilizing the retinal microvasculature. Effective prevention of VH could potentially eliminate nearly 60% of the reoperation requirements in this population. Proliferative diabetic retinopathy Vitreous hemorrhage Anti-VEGF Reoperation Survival analysis Surgical burden Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Proliferative diabetic retinopathy (PDR) remains a leading cause of irreversible vision loss worldwide[ 1 , 2 ]. While pars plana vitrectomy (PPV) has revolutionized the management of PDR-related complications, post-operative vitreous hemorrhage (VH) remains a significant challenge, complicating post-surgical recovery for both clinicians and patients[ 3 , 4 ]. Despite advancements in surgical instrumentation and techniques, the reported incidence of recurrent VH varies widely, ranging from 10% to over 70%[ 3 , 5 – 7 ], often leading to delayed visual rehabilitation and an increased requirement for secondary surgical interventions. Historically, most clinical investigations have focused on early post-operative VH (occurring within 4 weeks), attributing it to residual blood or intraoperative maneuvers[ 8 , 9 ]. However, the long-term clinical course and cumulative risk of VH over a multi-year horizon remain poorly characterized[ 10 , 11 ]. Furthermore, while preoperative anti-vascular endothelial growth factor (VEGF) therapy is widely employed to facilitate surgical dissection and reduce intraoperative bleeding, its long-term protective efficacy and underlying mechanisms remain subjects of active debate[ 12 , 13 ]. Specifically, it remains unclear whether the reduced risk of VH associated with anti-VEGF is merely a byproduct of improved anatomical success (i.e., prevention of tractional retinal detachment, TRD) or a direct, sustained stabilization of the retinal microvasculature. A critical gap in the current literature is the lack of a standardized, long-term survival perspective that accounts for systemic metabolic factors, surgical complexity, and the dynamic nature of neovascularization[ 11 , 14 ]. Moreover, the quantifiable impact of recurrent VH on the overall secondary surgical burden—a key metric for healthcare resource allocation—has not been sufficiently established in large-scale longitudinal cohorts[ 15 ]. In this study, we conducted a 24-month survival analysis on a cohort of 735 PDR patients to identify independent predictors of long-term post-operative VH. By employing a multivariate Cox proportional hazards model and a unique sensitivity analysis that decoupled VH from anatomical failure (TRD), we aimed to: (1) delineate the cumulative incidence and temporal trends of VH over a 2-year period; (2) validate the direct vascular-stabilizing effect of preoperative anti-VEGF; and (3) quantify the clinical and surgical burden attributable to recurrent hemorrhage. Our findings provide a robust evidence-based framework for optimizing perioperative management and improving long-term prognosis in PDR surgery. Methods Study Design and Ethical Approval This single-center, retrospective cohort study was conducted at the Department of Ophthalmology, The First Affiliated Hospital of Shantou University Medical College, in adherence to the tenets of the Declaration of Helsinki. The study protocol was approved by the Institutional Review Board of the First Affiliated Hospital of Shantou University Medical College (Approval ID: B-2025-212). Patient Selection and Grouping A total of 1,325 patients with PDR who underwent pars plana vitrectomy (PPV) or combined phaco-vitrectomy (PPV&P) between January 2019 and January 2025 were screened. Exclusion criteria included: (1) prior vitrectomy or cataract surgery in the study eye; (2) baseline rubeosis iridis or neovascular glaucoma (NVG); (3) confounding ocular pathologies (e.g., age-related macular degeneration, high myopia with axial length > 26 mm, or retinal vascular occlusions); (4) intraoperative complications such as posterior capsule tear; and (5) incomplete follow-up or missing systemic markers. Ultimately, 735 eyes from 735 patients were included. Patients were stratified using a 24-month survival analysis: Group A: Developed post-operative VH within 24 months (n = 179). Group B: Remained VH-free for at least 24 months (n = 556)(Fig. 1 ).To ensure comparability, only VH events occurring within the first 24 months were used for primary grouping and analysis. Surgical Procedures All surgeries were performed by two experienced vitreoretinal surgeons following a standardized 23-gauge three-port PPV protocol. The procedure included core vitrectomy, meticulous membrane delamination and segmentation to relieve all fibrovascular traction, and comprehensive panretinal endophotocoagulation (PRP) extending to the ora serrata. Intravitreal tamponade (balanced salt solution, air, C3F8, or silicone oil) was selected at the surgeon's discretion. Preoperative anti-VEGF injections (Conbercept or Ranibizumab) were administered 2–14 days before surgery in selected cases to facilitate membrane dissection and reduce intraoperative bleeding[ 12 ]. Data Collection and Definitions Preoperative systemic markers included HbA1c and serum creatinine. Surgical complexity was assessed using the Kroll et al. traction grading system, incorporating the extent of neovascularization and detachment range based on clinical examination and imaging modalities such as optical coherence tomography (OCT) and fundus photography[ 16 ]. The primary outcome was the cumulative incidence of post-operative VH, defined as any recurrent hemorrhage obscuring retinal details for over three weeks. Secondary outcomes included final best-corrected visual acuity (LogMAR), the incidence of post-operative tractional retinal detachment (TRD), and the rate of secondary surgical interventions (reoperation). Statistical Analysis Continuous variables were compared using independent-sample t-tests or Wilcoxon rank-sum tests, and categorical variables using Chi-squared or Fisher’s exact tests. To analyze the association between post-operative VH and TRD, a Chi-square test was employed. Time-to-event data for post-operative VH were analyzed using the Kaplan-Meier method with Log-rank tests. Univariate and Multivariate Cox proportional hazards models were constructed to identify independent predictors of VH within 24 months. Variable selection for the multivariate model was based on a P-value < 0.10 in univariate analysis and clinical relevance, using a backward stepwise approach (Akaike Information Criterion). Model discrimination was assessed using Harrell’s C-index. A sensitivity analysis was performed by excluding all patients who developed post-operative TRD (n = 676) to evaluate the direct protective effect of anti-VEGF on vascular stability. Statistical analyses were performed using SPSS 25.0 and R (version 4.2.2). Two-sided P-values < 0.05 were considered significant. Results Baseline Characteristics and Systemic Profiles A total of 735 eyes from 735 patients with PDR were analyzed. Based on the 24-month survival analysis, 179 eyes (24.4%) experienced post-operative vitreous hemorrhage (VH) (Group A), while 556 eyes (75.6%) remained VH-free (Group B).The mean follow-up was 31.4 months, with no significant difference between groups (P = 0.236), ensuring an unbiased observation window. Patients in Group A were significantly younger (50.6 ± 9.6 vs. 53.4 ± 9.7 years; P = 0.001) and exhibited poorer metabolic control, including higher HbA1c (7.60 ± 1.41% vs. 7.31 ± 1.66%; P = 0.036) and elevated serum creatinine levels (114.96 ± 42.96 vs. 101.74 ± 69.38 µmol/L; P = 0.016). Regarding preoperative ocular status, Group A had a significantly lower rate of preoperative anti-VEGF injection (64.2% vs. 85.4%; P < 0.001) and history of PRP (25.1% vs. 34.7%; P = 0.022). Furthermore, Group A presented with higher surgical complexity, characterized by more severe fibrovascular traction (Severe: 50.3% vs. 32.0%; P < 0.001) and a higher prevalence of combined TRD and VH as the primary surgical indication (42.5% vs. 30.8%; P = 0.012). Surgical procedures, including surgery type, use of endolaser, and intraoperative TA, were comparable between groups (all P > 0.05; Table 1 ). Table 1 Baseline Demographic and Clinical Characteristics of Patients Stratified by the Occurrence of Post-operative Vitreous Hemorrhage (VH) Within 2 Years. Parameter No Post-op VH(n = 556) Post-op VH(n = 179) P Value Age, mean (SD), y 53.40(9.67) 50.61(9.61) 0.001 Sex, No. (%) Male 365(65.6) 116(64.8) 0.908 Female 191(34.4) 142(35.2) History of diabetes, mean (SD), y 8.71(6.28) 8.27(5.77) 0.410 HbA1c, mean (SD),% 7.31(1.66) 7.60(1.41) 0.036 Creatinine, mean (SD), umol/L 101.74(69.38) 114.96(42.96) 0.016 Previous anti‑VEGF within 2 weeks, No. (%) 475(85.4) 115(64.2) <0.001 Previous laser, No. (%) 193(34.7) 45(25.1) 0.022 Surgery indications, No. (%) VH 354(63.7) 97(54.2) TRD 31(5.6) 6(3.4) 0.012 TRD + VH 171(30.8) 76(42.5) Preoperative lens nuclear sclerosis, No. (%) Grade 0/1 344(61.9) 108(60.3) Grade 2 201(36.2) 64(35.8) 0.346 Grade 3/4 11(2.0) 7(3.9) Preoperative Grading of Traction, No. (%) Severe 178(32.0) 90(50.3) Mild or moderate 232(41.7) 59(33.0) <0.001 No traction 146(26.3) 30(16.8) Surgery type, No. (%) PPV 459(82.6) 144(80.4) 0.598 PPV&P 97(17.4) 35(19.6) Surgery Procedures Endotamponade, No. (%) BSS 365(65.6) 104(58.1) Air 21(3.8) 6(3.4) 0.113 Silicone Oil 121(21.8) 55(30.7) C3F8 gas 49(8.8) 14(7.8) Endolaser, No. (%) 550(98.9) 177(98.9) 0.811 TA injection, No. (%) 272(48.9) 80(44.7) 0.369 Preoperative IOP, mean (SD), mmHg 13.24(1.65) 13.28(1.63) 0.799 Preoperative BCVA,Snellen(logMAR), mean (SD) 1.58(0.58) 1.59(0.53) 0.896 Follow-up time, mean (SD), y 31.67(10.52) 30.62(9.98) 0.236 Nuclear sclerosis was assessed at the slit lamp and classified as follows:Grade 0: Clear lens.Grade 1: Early nuclear sclerosis with mild yellow discoloration of the posterior lens in the slit beam.Grade 2: Yellow discoloration throughout the lens.Grade 3: Yellow-brown discoloration throughout the lens.Grade 4: Brown discoloration of the entire lens. Preoperative proliferative traction was graded as no traction(complete posterior vitreous detachment), mild (localized fibrosis without macular involvement), moderate (multifocal fibrosis with partial macular traction), or severe (extensive fibrosis with macular detachment or broad RD), based on clinical and imaging assessment, incorporating extent of neovascularization and detachment range. Continuous variables are presented as mean (standard deviation) and compared using the Student’s t-test or Wilcoxon rank-sum test. Categorical variables are presented as number (percentage) and compared using the Chi-square test or Fisher’s exact test. Independent Predictors of Post-operative VH Univariate Cox regression identified younger age, higher HbA1c, elevated creatinine, severe traction, and silicone oil tamponade as risk factors, while preoperative anti-VEGF and laser were protective (Table 2 ). Table 2 Univariate and Multivariate Cox Proportional Hazards Analysis for Post-operative VH within 24 Months Variable Univariate HR (95% CI) P Value Multivariate HR (95% CI) P Value Demographics Age (per 10 year increase) 0.80 (0.60–0.90) 0.001 0.89 (0.66–0.96) 0.015 Sex (Female vs. Male) 1.06 (0.78–1.44) 0.704 - - Systemic Factors DM Duration (per year) 0.99 (0.97–1.01) 0.451 - - HbA1c (%) 1.10 (1.01–1.20) 0.029 1.11 (1.01–1.21) 0.031 Creatinine (per 50 µmol/L increase) 1.10 (1.05–1.20) 0.033 1.10 (1.05–1.20) 0.008 Preoperative Status Anti-VEGF within 2 weeks 0.37 (0.27–0.50) < 0.001 0.37 (0.27–0.51) < 0.001 Preoperative Laser 0.66 (0.47–0.92) 0.015 0.64 (0.46–0.90) 0.010 Surgery indications VH Reference - Reference - TRD 0.71 (0.31–1.61) 0.411 - - TRD + VH 1.52 (1.13–2.05) 0.006 - - Traction Grade No traction Reference - Reference - Mild or moderate 1.16 (0.75–1.81) 0.498 1.10 (0.70–1.73) 0.686 Severe 2.15 (1.42–3.25) < 0.001 1.93 (1.26–2.95) 0.003 Surgical Factors Surgery Type (PPV vs. PPV&P) 0.79 (0.55–1.14) 0.212 - - Tamponade Type BSS Reference - - - Air 0.89 (0.39–2.02) 0.774 - - C3F8 gas 0.97 (0.55–1.69) 0.904 - - Silicone Oil 1.55 (1.12–2.15) 0.009 - - Model Performance: The multivariate model demonstrated a good discriminative ability with a C-index of 0.68 (95% CI, 0.64–0.72). Variable Selection: Candidate variables with P < 0.10 in the univariate analysis or those clinically relevant (e.g., Age) were entered into the final multivariate Cox proportional hazards model. A backward stepwise selection based on the Akaike Information Criterion (AIC) was employed to refine the model. Statistical Robustness: The proportional hazards assumption was checked using Schoenfeld residuals. Although the global test showed a minor deviation ( P = 0.001), a sensitivity analysis using a stratified Cox model confirmed that the hazard ratios for the primary variable (Anti-VEGF) remained highly consistent (HR 0.37, P < 0.001). Multicollinearity was ruled out with all variance inflation factors (VIF) < 3.0. The multivariate Cox model (C-index = 0.68) confirmed that preoperative anti-VEGF injection was the most potent protective factor, associated with a 63% reduction in VH hazard (HR 0.37; 95% CI, 0.27–0.51; P < 0.001). Preoperative laser also remained independently protective (HR 0.64; P = 0.010). Conversely, independent risk factors included severe traction (HR 1.93; P = 0.003), younger age (per 10-y increase: HR 0.89; P = 0.015), higher HbA1c (HR 1.11; P = 0.031), and elevated creatinine (per 50 µmol/L increase: HR 1.10; P = 0.008). A stratified Cox analysis confirmed the robustness of the anti-VEGF protective effect across different traction grades (HR 0.37; P < 0.001; Fig. 2 ). Temporal Trends and Cumulative Incidence Kaplan-Meier estimates revealed an overall cumulative VH incidence of 18.4% (95% CI: 15.5–21.2%) at 12 months and 25.7% (95% CI: 22.3–28.9%) at 24 months (Fig. 3 A). The protective impact of anti-VEGF was striking: the 24-month cumulative incidence in the anti-VEGF group was only 20.7%, compared to 46.6% in the non-injected group (Log-rank P < 0.001; Fig. 3 B). Anatomical severity also dictated long-term risk; the severe traction group showed an accelerated cumulative incidence, rising from 24.2% at 12 months to 37.3% at 24 months, significantly outperforming milder traction grades (Log-rank P < 0.001; Fig. 3 C). Sensitivity Analysis: Direct Vascular Stabilization To isolate the direct pharmacotherapeutic effect of anti-VEGF from anatomical outcomes, we first confirmed that post-operative VH and TRD were statistically independent events (χ² = 0.0017, P = 0.967). In a “pure hemorrhage model” excluding all patients with post-operative TRD (N = 676), the protective effect of anti-VEGF remained highly robust (HR 0.32; 95% CI, 0.23–0.44; P < 0.001). Other factors, including age, laser history, and traction grade, maintained their predictive significance (Table 3 ). This consistency (C-index = 0.696) confirms that anti-VEGF directly stabilizes the retinal microvasculature independent of anatomical success, providing compelling evidence for a sustained “vascular buffer” effect. Table 3 Sensitivity analysis of risk factors for post-operative VH in patients without post-operative TRD (N = 676). Variable Hazard Ratio (95% CI) z value P Value Demographics Age (per 10 year increase) 0.77 (0.62–0.93) -2.77 0.006 Systemic Factors HbA1c (%) 1.10 (1.00–1.21) 1.94 0.052 Creatinine (per 50 µmol/L increase) 1.12 (1.02–1.22) 2.35 0.019 Ocular Factors Preoperative Anti-VEGF within 2 weeks 0.32 (0.23–0.44) -6.89 < 0.001 Preoperative Laser 0.61 (0.43–0.87) -2.73 0.006 Traction Grade No traction Reference - - Mild or moderate 1.15 (0.71–1.84) 0.57 0.572 Severe 2.11 (1.35–3.30) 3.27 0.001 Model Performance: The C-index for this sensitivity model was 0.696, indicating high discriminative power in the absence of post-operative TRD. Rationale: This sensitivity analysis was conducted to evaluate whether the protective effect of anti-VEGF was independent of its potential role in preventing anatomical failure (TRD). Association Test: A Chi-square test confirmed that post-operative VH and post-operative TRD were independent events in this cohort ( X ² = 0.0017, P = 0.967). Abbreviations : VH, vitreous hemorrhage; Anti-VEGF, anti-vascular endothelial growth factor; TRD, tractional retinal detachment; HR, hazard ratio; CI, confidence interval. Clinical Consequences and Surgical Burden Post-operative VH was associated with significantly inferior functional recovery and increased surgical burden. Patients in Group A achieved a poorer final visual acuity (1.33 ± 0.75 vs. 0.92 ± 0.60 LogMAR; P < 0.001; Fig. 4 A). The reoperation rate was more than fourfold higher in the VH group compared to the non-VH group (31.3% vs. 7.2%; Fig. 4 B). Among the 96 eyes (13.1% of total) requiring secondary PPV, recurrent VH alone was the leading indication (43.8%), followed by post-operative TRD (41.7%) and combined VH/TRD (14.6%; Table 4 ). Crucially, vitreous hemorrhage-related complications represented 58.4% of the cumulative secondary surgical burden. Table 4 Primary indications for secondary pars plana vitrectomy within 2 years (N = 96). Primary Indication for Reoperation Count (n = 96) Percentage (%) Hemorrhage-related causes (56) (58.4%) - Recurrent VH alone 42 43.8% - Combined VH and TRD 14 14.6% Anatomical failure (40) (41.7%) - Post-operative TRD alone 40 41.7% Total 96 100.0% Abbreviations : VH, vitreous hemorrhage; TRD, tractional retinal detachment. Discussion In this retrospective cohort study of 735 PDR patients, we characterized the 24-month clinical course of post-operative VH using a 24-month survival analysis. Our findings reveal that post-operative VH is not merely a transient early complication but a persistent risk that significantly compromises long-term visual recovery and drives the majority of secondary surgical interventions. Most importantly, we demonstrated that preoperative anti-VEGF injection confers a robust, 24-month protective effect against recurrent hemorrhage, an effect that is independent of anatomical success. The Role of Anti-VEGF: From Acute De-bulking to Long-term Vascular Quiescence A pivotal finding of our study is the 63% reduction in VH hazard (HR 0.37) associated with preoperative anti-VEGF therapy, a protective effect that persisted throughout the 24-month horizon. While previous literature primarily emphasizes the perioperative benefits of anti-VEGF—such as facilitating membrane dissection and minimizing intraoperative bleeding [ 17 ]—our long-term data suggest a more profound, sustained pharmacological impact. A critical paradox in clinical practice is how a single preoperative injection, with a vitreous half-life typically measured in weeks, can confer protection for up to two years. We propose that this sustained benefit is not a result of prolonged drug presence, but rather a consequence of permanent morphological remodeling of the retinal microvasculature[ 12 , 18 ]. Preoperative VEGF inhibition induces the "pruning" and regression of fragile, active neovascularization, converting engorged, thin-walled vessels into non-functional, fibrotic stalks[ 10 , 19 , 20 ]. This pharmacological "pre-conditioning" significantly mitigates iatrogenic mechanical trauma to the retinal vessels during surgical manipulation, thereby preventing the formation of occult micro-vascular stumps that often serve as the source of late-onset recurrent hemorrhage. Furthermore, our sensitivity analysis using the "pure hemorrhage model" (HR 0.32 in the TRD-excluded subgroup) provides compelling evidence that this protection is independent of anatomical success. Even in eyes that achieved complete traction relief and retinal reattachment, those without preoperative anti-VEGF remained at a significantly higher risk of bleeding. This suggests that anti-VEGF therapy creates a long-term "vascular buffer" by altering the pro-angiogenic microenvironment[ 12 ]. By reducing residual intraocular blood—which is itself a potent pro-inflammatory and pro-angiogenic stimulus—anti-VEGF effectively breaks the "hemorrhage-inflammation-neovascularization" vicious cycle[ 21 , 22 ], maintaining long-term microvascular quiescence regardless of whether the initial surgical indication was tractional or exudative. Systemic and Ocular Risk Factors Our multivariate analysis identified younger age, elevated HbA1c, and high serum creatinine as independent systemic predictors of post-operative VH[ 5 , 12 , 23 – 26 ]. Younger patients often present with more aggressive fibrovascular proliferation, potentially driven by higher levels of growth factors[ 5 , 26 , 27 ]. The associations with HbA1c and creatinine underscore the critical role of the systemic microenvironment; poor glycemic control and renal impairment likely reflect a state of chronic endothelial dysfunction and increased vascular permeability, which predisposes the eye to recurrent bleeding even after successful traction relief[ 25 , 26 ]. Furthermore, severe preoperative fibrovascular traction nearly doubled the risk of VH[ 12 , 24 ]. This suggests that in eyes with advanced proliferative disease, the mechanical complexity of the index surgery may leave behind a more pro-angiogenic environment, necessitating even more vigilant perioperative management. The Burden of Reoperation: A Paradigm Shift in Post-operative PDR Management The most compelling evidence of the clinical impact of post-operative VH lies in its disproportionate contribution to the secondary surgical burden. Our analysis reveals a staggering finding: vitreous hemorrhage-related complications accounted for 58.4% of all secondary surgical interventions within the 24-month follow-up period. This indicates that more than half of the revisional surgical workload in PDR management is driven not by anatomical failure, but by vascular instability. The reoperation rate in the VH group was more than four times higher than that of the non-VH group (31.3% vs. 7.2%), highlighting a profound disparity in resource utilization and patient morbidity. Critically, our data demonstrate that recurrent VH has surpassed tractional retinal detachment (TRD) as the primary indication for secondary vitrectomy. Historically, vitreoretinal surgeons have prioritized "anatomical success"—the relief of traction and retinal reattachment—as the gold standard of PDR surgery[ 28 ]. However, our findings challenge this traditional hierarchy. While TRD remains a grave complication, it is the persistent or recurrent hemorrhage that constitutes the "lion's share" of the long-term surgical attrition. This shift in perspective is vital: it suggests that a surgery can be an anatomical "success" yet a clinical "failure" if the retinal microvasculature remains prone to bleeding. From a public health and socioeconomic perspective, the implications are substantial. Each reoperation represents not only an escalation in healthcare costs and a strain on surgical facilities but also a significant psychological and functional setback for the patient[ 29 , 30 ]. Our study quantifies for the first time that nearly 60% of the reoperation burden could theoretically be eliminated through effective prevention of post-operative VH. This identifies preoperative anti-VEGF therapy and stringent systemic metabolic control not merely as "adjuncts," but as essential strategies for enhancing the cost-effectiveness and long-term viability of PDR surgery. By stabilizing the vascular environment, we do more than clear the vitreous; we fundamentally reduce the cumulative "surgical burden" on the healthcare system. Strengths and Limitations The strengths of this study include its large sample size, the standardized 24-month survival analysis, and the use of sensitivity models to isolate vascular mechanisms. However, several limitations should be noted. As a retrospective study, the timing and choice of anti-VEGF agents were at the surgeon's discretion, which may introduce selection bias. Additionally, while we controlled for major systemic markers, other factors like blood pressure variability and use of antiplatelet medications were not fully accounted for. Conclusion In conclusion, post-operative VH is a primary driver of long-term visual impairment and healthcare resource utilization in PDR management. Preoperative anti-VEGF therapy provides a robust, sustained protective effect by stabilizing the retinal microvasculature—independent of anatomical outcomes. Implementation of preoperative anti-VEGF, combined with stringent systemic metabolic control, could theoretically mitigate nearly 60% of the reoperation burden in this population, offering a cost-effective strategy to reduce the overall surgical workload in PDR care. Declarations Acknowledgments None. Conflicts of Interest The authors declare no conflicts of interest. Data Availability Statement The data supporting the findings of this study are available from the corresponding author upon reasonable request. Due to their size, the raw datasets cannot be deposited in a public repository but can be accessed following a justified inquiry. Funding: This research received no external funding. Ethics approval and consent to participate: This study was approved by the Institutional Review Board of the First Affiliated Hospital of Shantou University Medical College (Approval ID: B-2025-212). Due to the retrospective nature of the study, the requirement for informed consent was waived by the IRB. Author Contributions: Yuxian Lin: Data curation, Formal analysis, Methodology, Writing – original draft. Ruibin Wu: Data curation, Supervision. Gengjia Li: Conceptualization, Supervision, Writing – review & editing, Project administration. References Teo ZL, Tham YC, Yu M, Chee ML, Rim TH, Cheung N, Bikbov MM, Wang YX, Tang Y, Lu Y et al : Global Prevalence of Diabetic Retinopathy and Projection of Burden through 2045: Systematic Review and Meta-analysis . Ophthalmology 2021, 128 (11):1580–1591. 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Zhao M, Chandra A, Xu J, Li J: Factors related to postoperative vitreous hemorrhage after small-gauge vitrectomy in proliferative diabetic retinopathy patients . BMC Ophthalmol 2023, 23 (1):215. Takayama K, Someya H, Yokoyama H, Kimura T, Takamura Y, Morioka M, Sameshima S, Ueda T, Ogata N, Kitano S et al : Prognostic factors of revitrectomy for complications in eyes with proliferative diabetic retinopathy: a retrospective multicentre study . Acta Ophthalmol 2020, 98 (4):e434–e439. Kroll P, Rodrigues EB, Hoerle S: Pathogenesis and classification of proliferative diabetic vitreoretinopathy . Ophthalmologica 2007, 221 (2):78–94. Bahr TA, Bakri SJ: Update on the Management of Diabetic Retinopathy: Anti-VEGF Agents for the Prevention of Complications and Progression of Nonproliferative and Proliferative Retinopathy . Life (Basel) 2023, 13 (5). Kuiper EJ, Van Nieuwenhoven FA, de Smet MD, van Meurs JC, Tanck MW, Oliver N, Klaassen I, Van Noorden CJ, Goldschmeding R, Schlingemann RO: The angio-fibrotic switch of VEGF and CTGF in proliferative diabetic retinopathy . PLoS One 2008, 3 (7):e2675. Dervenis P, Dervenis N, Smith JM, Steel DH: Anti-vascular endothelial growth factors in combination with vitrectomy for complications of proliferative diabetic retinopathy . Cochrane Database Syst Rev 2023, 5 (5):Cd008214. Qu J, Chen X, Liu Q, Wang F, Li M, Zhou Q, Yao J, Li X: Prophylactic intravitreal injection of aflibercept for preventing postvitrectomy hemorrhage in proliferative diabetic retinopathy: A randomized controlled trial . Front Public Health 2022, 10 :1067670. El Annan J, Carvounis PE: Current management of vitreous hemorrhage due to proliferative diabetic retinopathy . Int Ophthalmol Clin 2014, 54 (2):141–153. Semeraro F, Cancarini A, dell'Omo R, Rezzola S, Romano MR, Costagliola C: Diabetic Retinopathy: Vascular and Inflammatory Disease . J Diabetes Res 2015, 2015 :582060. Yilmaz U, Akçaoğlu T, Avunduk MA, Kaya H, Parça O: Investigation of the recurrent vitreous hemorrhage risk factors after early 25G vitrectomy in diabetic vitreous hemorrhage . Medicine (Baltimore) 2024, 103 (3):e36963. Li G, Wu R, Zhang X, Zheng M, Chen Q: Combined phacoemulsification and vitrectomy for proliferative diabetic retinopathy: an increased risk of early recurrence but not long-term neovascular glaucoma . Int J Retina Vitreous 2025, 11 (1):130. Kameda Y, Saeki T, Hanai K, Suzuki Y, Uchigata Y, Babazono T, Kitano S: Is Chronic Kidney Disease Affecting the Postoperative Complications of Vitrectomy for Proliferative Diabetic Retinopathy? J Clin Med 2021, 10 (22). Takayama K, Someya H, Yokoyama H, Takamura Y, Morioka M, Sameshima S, Ueda T, Kitano S, Tashiro M, Sugimoto M et al : Risk Factors of Neovascular Glaucoma After 25-gauge Vitrectomy for Proliferative Diabetic Retinopathy with Vitreous Hemorrhage: A Retrospective Multicenter Study . Sci Rep 2019, 9 (1):14858. Ke D, Hong Y, Jiang X, Sun X: Clinical Features and Vitreous Biomarkers of Early-Onset Type 2 Diabetes Mellitus Complicated with Proliferative Diabetic Retinopathy . Diabetes Metab Syndr Obes 2022, 15 :1293–1303. Hu X, Pan Q, Zheng J, Song Z, Zhang Z: Reoperation following vitrectomy for diabetic vitreous hemorrhage with versus without preoperative intravitreal bevacizumab . BMC Ophthalmol 2019, 19 (1):200. Sharma S, Hollands H, Brown GC, Brown MM, Shah GK, Sharma SM: The cost-effectiveness of early vitrectomy for the treatment of vitreous hemorrhage in diabetic retinopathy . Curr Opin Ophthalmol 2001, 12 (3):230–234. Guo H, Li W, Wang K, Nie Z, Zhang X, Bai S, Duan N, Li X, Hu B: Analysis of Risk Factors for Revitrectomy in Eyes with Diabetic Vitreous Hemorrhage . Diabetes Metab Syndr Obes 2023, 16 :2865–2874. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 21 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviews received at journal 07 Apr, 2026 Reviewers agreed at journal 04 Apr, 2026 Reviewers agreed at journal 04 Apr, 2026 Reviewers agreed at journal 04 Apr, 2026 Reviewers agreed at journal 04 Apr, 2026 Reviewers invited by journal 18 Mar, 2026 Editor assigned by journal 18 Mar, 2026 Submission checks completed at journal 18 Mar, 2026 First submitted to journal 13 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9117069","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":610127231,"identity":"c2e6fe29-60dc-443b-9dac-f30517f85566","order_by":0,"name":"Yuxian Lin","email":"","orcid":"","institution":"The First Affiliated Hospital of Shantou University Medical College","correspondingAuthor":false,"prefix":"","firstName":"Yuxian","middleName":"","lastName":"Lin","suffix":""},{"id":610127232,"identity":"f05be2a0-7660-446e-95e6-a8ed4ab4dba1","order_by":1,"name":"Ruibin Wu","email":"","orcid":"","institution":"The First Affiliated Hospital of Shantou University Medical College","correspondingAuthor":false,"prefix":"","firstName":"Ruibin","middleName":"","lastName":"Wu","suffix":""},{"id":610127233,"identity":"411610d8-8200-439c-9176-b970a96c88b4","order_by":2,"name":"Gengjia Li","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA30lEQVRIiWNgGAWjYBACA2YwxcbDwN7/8EFCRQ0pWnjOMBs8OHOMCC1wlkQOm+TDFmYitLCzX3xc8ItPhr8h91hFYgMbA397dwIBh/EUG8/sY+OROHAu7UbiDhkGiTNnNxDSkibN2wP0y8EGsxuJZ9gYDCRyCWpJ/w3SIn+YwawgsY2ZGC3sx5h5frDxGBzjMWMgUgsPszRvAxuP4Rm2ZImEM8d4CPrFvv/4w888f47Zy91/fPDjj4oaOf72XvxaGBh4DBgY2xAxyENAOQiwP2Bg+ENEOhkFo2AUjIKRCwDu/kR1nbkAFAAAAABJRU5ErkJggg==","orcid":"","institution":"The First Affiliated Hospital of Shantou University Medical College","correspondingAuthor":true,"prefix":"","firstName":"Gengjia","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2026-03-13 17:23:25","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9117069/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9117069/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105318795,"identity":"d540a772-4513-45a6-85ba-33b1da1ef752","added_by":"auto","created_at":"2026-03-24 16:55:55","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":882925,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eFlowchart of patient enrollment and study design.\u003c/strong\u003e\u003cbr\u003e\nA total of 1325 patients with proliferative diabetic retinopathy (PDR) who underwent pars plana vitrectomy (PPV) or combined phaco-vitrectomy (PPV\u0026amp;P) were initially screened. After excluding 186 cases with ineligible ocular conditions and 404 cases with insufficient follow-up or incomplete data, 735 patients were included in the final analytical cohort. These patients were categorized into Group A (Post-operative VH within 24 months, n = 179) and Group B (No post-operative VH within 24 months, n = 556). To evaluate the independent effect of risk factors, a sensitivity analysis was performed on a subset of 676 patients by excluding those who developed post-operative tractional retinal detachment (TRD).\u003cbr\u003e\n \u003cem\u003eAbbreviations:VH: vitreous hemorrhage; PDR: proliferative diabetic retinopathy; NVG: neovascular glaucoma; RVO: retinal vein occlusion; AMD: age-related macular degeneration; TRD: tractional retinal detachment.\u003c/em\u003e\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-9117069/v1/51de0fe0cf7e954aea9f9b76.png"},{"id":105318968,"identity":"ff155f7a-bba9-46c2-989d-d63a3af75aa7","added_by":"auto","created_at":"2026-03-24 16:56:12","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":344984,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eForest plot of independent predictors for post-operative vitreous hemorrhage (VH) within 24 months.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe forest plot displays the hazard ratios (HR) and 95% confidence intervals (CI) derived from the final multivariate Cox proportional hazards model. The vertical dashed line represents a hazard ratio of 1.0 (null effect).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAbbreviations: HR, hazard ratio; CI, confidence interval; Anti-VEGF, anti-vascular endothelial growth factor; HbA1c, glycated hemoglobin\u003c/em\u003e.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-9117069/v1/1b162f464867d3e3be775d62.png"},{"id":105318964,"identity":"60d9dc21-51aa-4cc0-8807-87297b57d604","added_by":"auto","created_at":"2026-03-24 16:56:10","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":3102034,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eCumulative incidence of post-operative vitreous hemorrhage (VH) during the 24-month follow-up period.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e(A) Overall Population (N=735)\u003c/strong\u003e: The cumulative incidence of VH for the total cohort was 18.4% (95% CI: 15.5–21.2%) at 12 months, and 25.7% (95% CI: 22.3–28.9%) at 24 months.\u003cstrong\u003e(B) Stratified by Preoperative Anti-VEGF\u003c/strong\u003e: Patients who received preoperative anti-VEGF injection (blue line) showed a significantly lower cumulative incidence of VH compared to those without (red line; Log-rank \u003cem\u003eP\u003c/em\u003e \u0026lt; 0.001). At 24 months, the risk in the non-anti-VEGF group (46.6%) was more than double that of the anti-VEGF group (20.7%).\u003cstrong\u003e(C) Stratified by Tractional Severity\u003c/strong\u003e: The cumulative hazard increased significantly with higher traction grades (Log-rank \u003cem\u003eP\u003c/em\u003e\u0026lt; 0.001). Severe traction (blue line) exhibited the highest risk, reaching a 37.3% incidence at 24 months.\u003cem\u003eShaded areas represent 95% confidence intervals. The tables below the plots provide the \"Number at risk\" (eyes remaining VH-free) at each 6-month interval.\u003c/em\u003e\u003c/p\u003e","description":"","filename":"Figure3.png","url":"https://assets-eu.researchsquare.com/files/rs-9117069/v1/b699552231e1ba3eb87702ff.png"},{"id":105318963,"identity":"e32a2111-54b4-4575-9b71-b8f3b71bbda2","added_by":"auto","created_at":"2026-03-24 16:56:09","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":329993,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eImpact of post-operative vitreous hemorrhage (VH) on visual recovery and surgical burden within 2 years. (A) Final Visual Outcome\u003c/strong\u003e: Comparison of final LogMAR visual acuity (VA) between the VH and non-VH groups. Patients who experienced post-operative VH had significantly poorer visual outcomes (1.33 ± 0.75 vs. 0.92 ± 0.60; \u003cem\u003ep\u003c/em\u003e\u0026lt; 0.001). Boxplots represent the median and interquartile range; whiskers represent the 1.5x IQR.\u003cstrong\u003e(B) Reoperation Rate\u003c/strong\u003e: Comparison of the incidence of secondary pars plana vitrectomy (PPV). The reoperation rate was more than four times higher in the VH group compared to the non-VH group (31.3% vs. 7.2%).\u003c/p\u003e","description":"","filename":"Figure4.png","url":"https://assets-eu.researchsquare.com/files/rs-9117069/v1/a615fac26a5fd77672cadcb5.png"},{"id":105565629,"identity":"758ed0f6-ab12-4f12-a32f-b7fbc2e0f27d","added_by":"auto","created_at":"2026-03-27 12:53:52","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":6493886,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9117069/v1/f8b63716-9cae-486f-9617-436d6b2d92c8.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Preoperative Anti-VEGF and the Cumulative Risk of Post-operative Vitreous Hemorrhage in PDR: A 2-Year Survival Analysis and Evaluation of Surgical Burden","fulltext":[{"header":"Introduction","content":"\u003cp\u003eProliferative diabetic retinopathy (PDR) remains a leading cause of irreversible vision loss worldwide[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. While pars plana vitrectomy (PPV) has revolutionized the management of PDR-related complications, post-operative vitreous hemorrhage (VH) remains a significant challenge, complicating post-surgical recovery for both clinicians and patients[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Despite advancements in surgical instrumentation and techniques, the reported incidence of recurrent VH varies widely, ranging from 10% to over 70%[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan additionalcitationids=\"CR6\" citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], often leading to delayed visual rehabilitation and an increased requirement for secondary surgical interventions.\u003c/p\u003e \u003cp\u003eHistorically, most clinical investigations have focused on early post-operative VH (occurring within 4 weeks), attributing it to residual blood or intraoperative maneuvers[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. However, the long-term clinical course and cumulative risk of VH over a multi-year horizon remain poorly characterized[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Furthermore, while preoperative anti-vascular endothelial growth factor (VEGF) therapy is widely employed to facilitate surgical dissection and reduce intraoperative bleeding, its long-term protective efficacy and underlying mechanisms remain subjects of active debate[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Specifically, it remains unclear whether the reduced risk of VH associated with anti-VEGF is merely a byproduct of improved anatomical success (i.e., prevention of tractional retinal detachment, TRD) or a direct, sustained stabilization of the retinal microvasculature.\u003c/p\u003e \u003cp\u003eA critical gap in the current literature is the lack of a standardized, long-term survival perspective that accounts for systemic metabolic factors, surgical complexity, and the dynamic nature of neovascularization[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Moreover, the quantifiable impact of recurrent VH on the overall secondary surgical burden\u0026mdash;a key metric for healthcare resource allocation\u0026mdash;has not been sufficiently established in large-scale longitudinal cohorts[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn this study, we conducted a 24-month survival analysis on a cohort of 735 PDR patients to identify independent predictors of long-term post-operative VH. By employing a multivariate Cox proportional hazards model and a unique sensitivity analysis that decoupled VH from anatomical failure (TRD), we aimed to: (1) delineate the cumulative incidence and temporal trends of VH over a 2-year period; (2) validate the direct vascular-stabilizing effect of preoperative anti-VEGF; and (3) quantify the clinical and surgical burden attributable to recurrent hemorrhage. Our findings provide a robust evidence-based framework for optimizing perioperative management and improving long-term prognosis in PDR surgery.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy Design and Ethical Approval\u003c/h2\u003e \u003cp\u003e This single-center, retrospective cohort study was conducted at the Department of Ophthalmology, The First Affiliated Hospital of Shantou University Medical College, in adherence to the tenets of the Declaration of Helsinki. The study protocol was approved by the Institutional Review Board of the First Affiliated Hospital of Shantou University Medical College (Approval ID: B-2025-212).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePatient Selection and Grouping\u003c/h3\u003e\n\u003cp\u003eA total of 1,325 patients with PDR who underwent pars plana vitrectomy (PPV) or combined phaco-vitrectomy (PPV\u0026amp;P) between January 2019 and January 2025 were screened. Exclusion criteria included: (1) prior vitrectomy or cataract surgery in the study eye; (2) baseline rubeosis iridis or neovascular glaucoma (NVG); (3) confounding ocular pathologies (e.g., age-related macular degeneration, high myopia with axial length\u0026thinsp;\u0026gt;\u0026thinsp;26 mm, or retinal vascular occlusions); (4) intraoperative complications such as posterior capsule tear; and (5) incomplete follow-up or missing systemic markers.\u003c/p\u003e \u003cp\u003eUltimately, 735 eyes from 735 patients were included. Patients were stratified using a 24-month survival analysis: Group A: Developed post-operative VH within 24 months (n\u0026thinsp;=\u0026thinsp;179). Group B: Remained VH-free for at least 24 months (n\u0026thinsp;=\u0026thinsp;556)(Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).To ensure comparability, only VH events occurring within the first 24 months were used for primary grouping and analysis.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e\n\u003ch3\u003eSurgical Procedures\u003c/h3\u003e\n\u003cp\u003eAll surgeries were performed by two experienced vitreoretinal surgeons following a standardized 23-gauge three-port PPV protocol. The procedure included core vitrectomy, meticulous membrane delamination and segmentation to relieve all fibrovascular traction, and comprehensive panretinal endophotocoagulation (PRP) extending to the ora serrata. Intravitreal tamponade (balanced salt solution, air, C3F8, or silicone oil) was selected at the surgeon's discretion. Preoperative anti-VEGF injections (Conbercept or Ranibizumab) were administered 2\u0026ndash;14 days before surgery in selected cases to facilitate membrane dissection and reduce intraoperative bleeding[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\n\u003ch3\u003eData Collection and Definitions\u003c/h3\u003e\n\u003cp\u003ePreoperative systemic markers included HbA1c and serum creatinine. Surgical complexity was assessed using the Kroll et al. traction grading system, incorporating the extent of neovascularization and detachment range based on clinical examination and imaging modalities such as optical coherence tomography (OCT) and fundus photography[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe primary outcome was the cumulative incidence of post-operative VH, defined as any recurrent hemorrhage obscuring retinal details for over three weeks. Secondary outcomes included final best-corrected visual acuity (LogMAR), the incidence of post-operative tractional retinal detachment (TRD), and the rate of secondary surgical interventions (reoperation).\u003c/p\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003eStatistical Analysis\u003c/h2\u003e \u003cp\u003eContinuous variables were compared using independent-sample t-tests or Wilcoxon rank-sum tests, and categorical variables using Chi-squared or Fisher\u0026rsquo;s exact tests. To analyze the association between post-operative VH and TRD, a Chi-square test was employed.\u003c/p\u003e \u003cp\u003eTime-to-event data for post-operative VH were analyzed using the Kaplan-Meier method with Log-rank tests. Univariate and Multivariate Cox proportional hazards models were constructed to identify independent predictors of VH within 24 months. Variable selection for the multivariate model was based on a P-value\u0026thinsp;\u0026lt;\u0026thinsp;0.10 in univariate analysis and clinical relevance, using a backward stepwise approach (Akaike Information Criterion). Model discrimination was assessed using Harrell\u0026rsquo;s C-index.\u003c/p\u003e \u003cp\u003eA sensitivity analysis was performed by excluding all patients who developed post-operative TRD (n\u0026thinsp;=\u0026thinsp;676) to evaluate the direct protective effect of anti-VEGF on vascular stability. Statistical analyses were performed using SPSS 25.0 and R (version 4.2.2). Two-sided P-values\u0026thinsp;\u0026lt;\u0026thinsp;0.05 were considered significant.\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eBaseline Characteristics and Systemic Profiles\u003c/h2\u003e \u003cp\u003eA total of 735 eyes from 735 patients with PDR were analyzed. Based on the 24-month survival analysis, 179 eyes (24.4%) experienced post-operative vitreous hemorrhage (VH) (Group A), while 556 eyes (75.6%) remained VH-free (Group B).The mean follow-up was 31.4 months, with no significant difference between groups (P\u0026thinsp;=\u0026thinsp;0.236), ensuring an unbiased observation window.\u003c/p\u003e \u003cp\u003ePatients in Group A were significantly younger (50.6\u0026thinsp;\u0026plusmn;\u0026thinsp;9.6 vs. 53.4\u0026thinsp;\u0026plusmn;\u0026thinsp;9.7 years; P\u0026thinsp;=\u0026thinsp;0.001) and exhibited poorer metabolic control, including higher HbA1c (7.60\u0026thinsp;\u0026plusmn;\u0026thinsp;1.41% vs. 7.31\u0026thinsp;\u0026plusmn;\u0026thinsp;1.66%; P\u0026thinsp;=\u0026thinsp;0.036) and elevated serum creatinine levels (114.96\u0026thinsp;\u0026plusmn;\u0026thinsp;42.96 vs. 101.74\u0026thinsp;\u0026plusmn;\u0026thinsp;69.38 \u0026micro;mol/L; P\u0026thinsp;=\u0026thinsp;0.016).\u003c/p\u003e \u003cp\u003eRegarding preoperative ocular status, Group A had a significantly lower rate of preoperative anti-VEGF injection (64.2% vs. 85.4%; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and history of PRP (25.1% vs. 34.7%; P\u0026thinsp;=\u0026thinsp;0.022). Furthermore, Group A presented with higher surgical complexity, characterized by more severe fibrovascular traction (Severe: 50.3% vs. 32.0%; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and a higher prevalence of combined TRD and VH as the primary surgical indication (42.5% vs. 30.8%; P\u0026thinsp;=\u0026thinsp;0.012). Surgical procedures, including surgery type, use of endolaser, and intraoperative TA, were comparable between groups (all P\u0026thinsp;\u0026gt;\u0026thinsp;0.05; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\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\u003eBaseline Demographic and Clinical Characteristics of Patients Stratified by the Occurrence of Post-operative Vitreous Hemorrhage (VH) Within 2 Years.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParameter\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNo Post-op VH(n\u0026thinsp;=\u0026thinsp;556)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePost-op VH(n\u0026thinsp;=\u0026thinsp;179)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, mean (SD), y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e53.40(9.67)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e50.61(9.61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e365(65.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e116(64.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e0.908\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFemale\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e191(34.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e142(35.2)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHistory of diabetes, mean (SD), y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8.71(6.28)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e8.27(5.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.410\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHbA1c, mean (SD),%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e7.31(1.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.60(1.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.036\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCreatinine, mean (SD), umol/L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e101.74(69.38)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e114.96(42.96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.016\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrevious anti‑VEGF within 2 weeks, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e475(85.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e115(64.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrevious laser, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e193(34.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e45(25.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.022\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgery indications, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e354(63.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e97(54.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTRD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e31(5.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6(3.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.012\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTRD\u0026thinsp;+\u0026thinsp;VH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e171(30.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e76(42.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative lens nuclear sclerosis, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade 0/1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e344(61.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e108(60.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade 2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e201(36.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e64(35.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.346\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eGrade 3/4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e11(2.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7(3.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative Grading of Traction, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSevere\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e178(32.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e90(50.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMild or moderate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e232(41.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e59(33.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo traction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e146(26.3)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30(16.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgery type, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e459(82.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e144(80.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.598\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePPV\u0026amp;P\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e97(17.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e35(19.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgery Procedures\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEndotamponade, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBSS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e365(65.6)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e104(58.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAir\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21(3.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e6(3.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.113\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSilicone Oil\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e121(21.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e55(30.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC3F8 gas\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e49(8.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14(7.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eEndolaser, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e550(98.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e177(98.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.811\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTA injection, No. (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e272(48.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e80(44.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.369\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative IOP, mean (SD), mmHg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13.24(1.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e13.28(1.63)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.799\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative BCVA,Snellen(logMAR), mean (SD)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.58(0.58)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e1.59(0.53)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.896\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFollow-up time, mean (SD), y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e31.67(10.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30.62(9.98)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e0.236\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eNuclear sclerosis was assessed at the slit lamp and classified as follows:Grade 0: Clear lens.Grade 1: Early nuclear sclerosis with mild yellow discoloration of the posterior lens in the slit beam.Grade 2: Yellow discoloration throughout the lens.Grade 3: Yellow-brown discoloration throughout the lens.Grade 4: Brown discoloration of the entire lens.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003ePreoperative proliferative traction was graded as no traction(complete posterior vitreous detachment), mild (localized fibrosis without macular involvement), moderate (multifocal fibrosis with partial macular traction), or severe (extensive fibrosis with macular detachment or broad RD), based on clinical and imaging assessment, incorporating extent of neovascularization and detachment range.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eContinuous variables are presented as mean (standard deviation) and compared using the Student\u0026rsquo;s t-test or Wilcoxon rank-sum test. Categorical variables are presented as number (percentage) and compared using the Chi-square test or Fisher\u0026rsquo;s exact test.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eIndependent Predictors of Post-operative VH\u003c/h3\u003e\n\u003cp\u003eUnivariate Cox regression identified younger age, higher HbA1c, elevated creatinine, severe traction, and silicone oil tamponade as risk factors, while preoperative anti-VEGF and laser were protective (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eUnivariate and Multivariate Cox Proportional Hazards Analysis for Post-operative VH within 24 Months\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\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=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUnivariate HR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e Value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eMultivariate HR (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDemographics\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (per 10 year increase)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.80 (0.60\u0026ndash;0.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.89 (0.66\u0026ndash;0.96)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.015\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSex (Female vs. Male)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.06 (0.78\u0026ndash;1.44)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.704\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSystemic Factors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDM Duration (per year)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.99 (0.97\u0026ndash;1.01)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.451\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHbA1c (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.10 (1.01\u0026ndash;1.20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.029\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.11 (1.01\u0026ndash;1.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.031\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCreatinine (per 50 \u0026micro;mol/L increase)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.10 (1.05\u0026ndash;1.20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.033\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.10 (1.05\u0026ndash;1.20)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.008\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative Status\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAnti-VEGF within 2 weeks\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.37 (0.27\u0026ndash;0.50)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.37 (0.27\u0026ndash;0.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative Laser\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.66 (0.47\u0026ndash;0.92)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.015\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.64 (0.46\u0026ndash;0.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.010\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgery indications\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTRD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.71 (0.31\u0026ndash;1.61)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.411\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTRD\u0026thinsp;+\u0026thinsp;VH\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.52 (1.13\u0026ndash;2.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTraction Grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo traction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMild or moderate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.16 (0.75\u0026ndash;1.81)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.498\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.10 (0.70\u0026ndash;1.73)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.686\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSevere\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.15 (1.42\u0026ndash;3.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.93 (1.26\u0026ndash;2.95)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgical Factors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSurgery Type (PPV vs. PPV\u0026amp;P)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.79 (0.55\u0026ndash;1.14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.212\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTamponade Type\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBSS\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAir\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.89 (0.39\u0026ndash;2.02)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.774\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC3F8 gas\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.97 (0.55\u0026ndash;1.69)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.904\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSilicone Oil\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.55 (1.12\u0026ndash;2.15)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e0.009\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eModel Performance: The multivariate model demonstrated a good discriminative ability with a C-index of 0.68 (95% CI, 0.64\u0026ndash;0.72).\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eVariable Selection: Candidate variables with \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.10 in the univariate analysis or those clinically relevant (e.g., Age) were entered into the final multivariate Cox proportional hazards model. A backward stepwise selection based on the Akaike Information Criterion (AIC) was employed to refine the model.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003eStatistical Robustness: The proportional hazards assumption was checked using Schoenfeld residuals. Although the global test showed a minor deviation (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001), a sensitivity analysis using a stratified Cox model confirmed that the hazard ratios for the primary variable (Anti-VEGF) remained highly consistent (HR 0.37, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Multicollinearity was ruled out with all variance inflation factors (VIF)\u0026thinsp;\u0026lt;\u0026thinsp;3.0.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe multivariate Cox model (C-index\u0026thinsp;=\u0026thinsp;0.68) confirmed that preoperative anti-VEGF injection was the most potent protective factor, associated with a 63% reduction in VH hazard (HR 0.37; 95% CI, 0.27\u0026ndash;0.51; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Preoperative laser also remained independently protective (HR 0.64; P\u0026thinsp;=\u0026thinsp;0.010). Conversely, independent risk factors included severe traction (HR 1.93; P\u0026thinsp;=\u0026thinsp;0.003), younger age (per 10-y increase: HR 0.89; P\u0026thinsp;=\u0026thinsp;0.015), higher HbA1c (HR 1.11; P\u0026thinsp;=\u0026thinsp;0.031), and elevated creatinine (per 50 \u0026micro;mol/L increase: HR 1.10; P\u0026thinsp;=\u0026thinsp;0.008). A stratified Cox analysis confirmed the robustness of the anti-VEGF protective effect across different traction grades (HR 0.37; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eTemporal Trends and Cumulative Incidence\u003c/h2\u003e \u003cp\u003eKaplan-Meier estimates revealed an overall cumulative VH incidence of 18.4% (95% CI: 15.5\u0026ndash;21.2%) at 12 months and 25.7% (95% CI: 22.3\u0026ndash;28.9%) at 24 months (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eA).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe protective impact of anti-VEGF was striking: the 24-month cumulative incidence in the anti-VEGF group was only 20.7%, compared to 46.6% in the non-injected group (Log-rank P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eB). Anatomical severity also dictated long-term risk; the severe traction group showed an accelerated cumulative incidence, rising from 24.2% at 12 months to 37.3% at 24 months, significantly outperforming milder traction grades (Log-rank P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eC).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eSensitivity Analysis: Direct Vascular Stabilization\u003c/h2\u003e \u003cp\u003eTo isolate the direct pharmacotherapeutic effect of anti-VEGF from anatomical outcomes, we first confirmed that post-operative VH and TRD were statistically independent events (χ\u0026sup2; = 0.0017, P\u0026thinsp;=\u0026thinsp;0.967).\u003c/p\u003e \u003cp\u003eIn a \u0026ldquo;pure hemorrhage model\u0026rdquo; excluding all patients with post-operative TRD (N\u0026thinsp;=\u0026thinsp;676), the protective effect of anti-VEGF remained highly robust (HR 0.32; 95% CI, 0.23\u0026ndash;0.44; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Other factors, including age, laser history, and traction grade, maintained their predictive significance (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). This consistency (C-index\u0026thinsp;=\u0026thinsp;0.696) confirms that anti-VEGF directly stabilizes the retinal microvasculature independent of anatomical success, providing compelling evidence for a sustained \u0026ldquo;vascular buffer\u0026rdquo; effect.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSensitivity analysis of risk factors for post-operative VH in patients without post-operative TRD (N\u0026thinsp;=\u0026thinsp;676).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHazard Ratio (95% CI)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cem\u003ez\u003c/em\u003e value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eP\u003c/em\u003e Value\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eDemographics\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge (per 10 year increase)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.77 (0.62\u0026ndash;0.93)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-2.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSystemic Factors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHbA1c (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.10 (1.00\u0026ndash;1.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.052\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCreatinine (per 50 \u0026micro;mol/L increase)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.12 (1.02\u0026ndash;1.22)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.35\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.019\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOcular Factors\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative Anti-VEGF within 2 weeks\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e0.32 (0.23\u0026ndash;0.44)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e-6.89\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePreoperative Laser\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.61 (0.43\u0026ndash;0.87)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-2.73\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.006\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTraction Grade\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo traction\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eReference\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMild or moderate\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.15 (0.71\u0026ndash;1.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.572\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSevere\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.11 (1.35\u0026ndash;3.30)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.27\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eModel Performance: The C-index for this sensitivity model was 0.696, indicating high discriminative power in the absence of post-operative TRD.\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eRationale: This sensitivity analysis was conducted to evaluate whether the protective effect of anti-VEGF was independent of its potential role in preventing anatomical failure (TRD).\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003eAssociation Test: A Chi-square test confirmed that post-operative VH and post-operative TRD were independent events in this cohort (\u003cem\u003eX\u003c/em\u003e\u0026sup2; = 0.0017, P\u0026thinsp;=\u0026thinsp;0.967).\u003c/td\u003e\u003c/tr\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003cb\u003eAbbreviations\u003c/b\u003e: VH, vitreous hemorrhage; Anti-VEGF, anti-vascular endothelial growth factor; TRD, tractional retinal detachment; HR, hazard ratio; CI, confidence interval.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eClinical Consequences and Surgical Burden\u003c/h2\u003e \u003cp\u003ePost-operative VH was associated with significantly inferior functional recovery and increased surgical burden. Patients in Group A achieved a poorer final visual acuity (1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75 vs. 0.92\u0026thinsp;\u0026plusmn;\u0026thinsp;0.60 LogMAR; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001; Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe reoperation rate was more than fourfold higher in the VH group compared to the non-VH group (31.3% vs. 7.2%; Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB). Among the 96 eyes (13.1% of total) requiring secondary PPV, recurrent VH alone was the leading indication (43.8%), followed by post-operative TRD (41.7%) and combined VH/TRD (14.6%; Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Crucially, vitreous hemorrhage-related complications represented 58.4% of the cumulative secondary surgical burden.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePrimary indications for secondary pars plana vitrectomy within 2 years (N\u0026thinsp;=\u0026thinsp;96).\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimary Indication for Reoperation\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eCount (n\u0026thinsp;=\u0026thinsp;96)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePercentage (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHemorrhage-related causes\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e(56)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e(58.4%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- Recurrent VH alone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e43.8%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- Combined VH and TRD\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e14.6%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eAnatomical failure\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e(40)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e(41.7%)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e- Post-operative TRD alone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e41.7%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003e96\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003e100.0%\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003e\u003cb\u003eAbbreviations\u003c/b\u003e: VH, vitreous hemorrhage; TRD, tractional retinal detachment.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this retrospective cohort study of 735 PDR patients, we characterized the 24-month clinical course of post-operative VH using a 24-month survival analysis. Our findings reveal that post-operative VH is not merely a transient early complication but a persistent risk that significantly compromises long-term visual recovery and drives the majority of secondary surgical interventions. Most importantly, we demonstrated that preoperative anti-VEGF injection confers a robust, 24-month protective effect against recurrent hemorrhage, an effect that is independent of anatomical success.\u003c/p\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eThe Role of Anti-VEGF: From Acute De-bulking to Long-term Vascular Quiescence\u003c/h2\u003e \u003cp\u003eA pivotal finding of our study is the 63% reduction in VH hazard (HR 0.37) associated with preoperative anti-VEGF therapy, a protective effect that persisted throughout the 24-month horizon. While previous literature primarily emphasizes the perioperative benefits of anti-VEGF\u0026mdash;such as facilitating membrane dissection and minimizing intraoperative bleeding [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u0026mdash;our long-term data suggest a more profound, sustained pharmacological impact.\u003c/p\u003e \u003cp\u003eA critical paradox in clinical practice is how a single preoperative injection, with a vitreous half-life typically measured in weeks, can confer protection for up to two years. We propose that this sustained benefit is not a result of prolonged drug presence, but rather a consequence of permanent morphological remodeling of the retinal microvasculature[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Preoperative VEGF inhibition induces the \"pruning\" and regression of fragile, active neovascularization, converting engorged, thin-walled vessels into non-functional, fibrotic stalks[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. This pharmacological \"pre-conditioning\" significantly mitigates iatrogenic mechanical trauma to the retinal vessels during surgical manipulation, thereby preventing the formation of occult micro-vascular stumps that often serve as the source of late-onset recurrent hemorrhage.\u003c/p\u003e \u003cp\u003eFurthermore, our sensitivity analysis using the \"pure hemorrhage model\" (HR 0.32 in the TRD-excluded subgroup) provides compelling evidence that this protection is independent of anatomical success. Even in eyes that achieved complete traction relief and retinal reattachment, those without preoperative anti-VEGF remained at a significantly higher risk of bleeding. This suggests that anti-VEGF therapy creates a long-term \"vascular buffer\" by altering the pro-angiogenic microenvironment[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. By reducing residual intraocular blood\u0026mdash;which is itself a potent pro-inflammatory and pro-angiogenic stimulus\u0026mdash;anti-VEGF effectively breaks the \"hemorrhage-inflammation-neovascularization\" vicious cycle[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], maintaining long-term microvascular quiescence regardless of whether the initial surgical indication was tractional or exudative.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eSystemic and Ocular Risk Factors\u003c/h2\u003e \u003cp\u003eOur multivariate analysis identified younger age, elevated HbA1c, and high serum creatinine as independent systemic predictors of post-operative VH[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan additionalcitationids=\"CR24 CR25\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Younger patients often present with more aggressive fibrovascular proliferation, potentially driven by higher levels of growth factors[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. The associations with HbA1c and creatinine underscore the critical role of the systemic microenvironment; poor glycemic control and renal impairment likely reflect a state of chronic endothelial dysfunction and increased vascular permeability, which predisposes the eye to recurrent bleeding even after successful traction relief[\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Furthermore, severe preoperative fibrovascular traction nearly doubled the risk of VH[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. This suggests that in eyes with advanced proliferative disease, the mechanical complexity of the index surgery may leave behind a more pro-angiogenic environment, necessitating even more vigilant perioperative management.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003eThe Burden of Reoperation: A Paradigm Shift in Post-operative PDR Management\u003c/h2\u003e \u003cp\u003eThe most compelling evidence of the clinical impact of post-operative VH lies in its disproportionate contribution to the secondary surgical burden. Our analysis reveals a staggering finding: vitreous hemorrhage-related complications accounted for 58.4% of all secondary surgical interventions within the 24-month follow-up period. This indicates that more than half of the revisional surgical workload in PDR management is driven not by anatomical failure, but by vascular instability. The reoperation rate in the VH group was more than four times higher than that of the non-VH group (31.3% vs. 7.2%), highlighting a profound disparity in resource utilization and patient morbidity.\u003c/p\u003e \u003cp\u003eCritically, our data demonstrate that recurrent VH has surpassed tractional retinal detachment (TRD) as the primary indication for secondary vitrectomy. Historically, vitreoretinal surgeons have prioritized \"anatomical success\"\u0026mdash;the relief of traction and retinal reattachment\u0026mdash;as the gold standard of PDR surgery[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. However, our findings challenge this traditional hierarchy. While TRD remains a grave complication, it is the persistent or recurrent hemorrhage that constitutes the \"lion's share\" of the long-term surgical attrition. This shift in perspective is vital: it suggests that a surgery can be an anatomical \"success\" yet a clinical \"failure\" if the retinal microvasculature remains prone to bleeding.\u003c/p\u003e \u003cp\u003eFrom a public health and socioeconomic perspective, the implications are substantial. Each reoperation represents not only an escalation in healthcare costs and a strain on surgical facilities but also a significant psychological and functional setback for the patient[\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. Our study quantifies for the first time that nearly 60% of the reoperation burden could theoretically be eliminated through effective prevention of post-operative VH. This identifies preoperative anti-VEGF therapy and stringent systemic metabolic control not merely as \"adjuncts,\" but as essential strategies for enhancing the cost-effectiveness and long-term viability of PDR surgery. By stabilizing the vascular environment, we do more than clear the vitreous; we fundamentally reduce the cumulative \"surgical burden\" on the healthcare system.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003eStrengths and Limitations\u003c/h2\u003e \u003cp\u003eThe strengths of this study include its large sample size, the standardized 24-month survival analysis, and the use of sensitivity models to isolate vascular mechanisms.\u003c/p\u003e \u003cp\u003eHowever, several limitations should be noted. As a retrospective study, the timing and choice of anti-VEGF agents were at the surgeon's discretion, which may introduce selection bias. Additionally, while we controlled for major systemic markers, other factors like blood pressure variability and use of antiplatelet medications were not fully accounted for.\u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, post-operative VH is a primary driver of long-term visual impairment and healthcare resource utilization in PDR management. Preoperative anti-VEGF therapy provides a robust, sustained protective effect by stabilizing the retinal microvasculature\u0026mdash;independent of anatomical outcomes. Implementation of preoperative anti-VEGF, combined with stringent systemic metabolic control, could theoretically mitigate nearly 60% of the reoperation burden in this population, offering a cost-effective strategy to reduce the overall surgical workload in PDR care.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data supporting the findings of this study are available from the corresponding author upon reasonable request. Due to their size, the raw datasets cannot be deposited in a public repository but can be accessed following a justified inquiry.\u003c/p\u003e \u003cp\u003e\u003cstrong\u003eFunding:\u0026nbsp;\u003c/strong\u003eThis research received no external funding.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u003c/strong\u003eThis study was approved by the Institutional Review Board of the First Affiliated Hospital of Shantou University Medical College (Approval ID: B-2025-212). Due to the retrospective nature of the study, the requirement for informed consent was waived by the IRB.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYuxian Lin: Data curation, Formal analysis, Methodology, Writing – original draft.\u003c/p\u003e\n\u003cp\u003eRuibin Wu: Data curation, Supervision.\u003c/p\u003e\n\u003cp\u003eGengjia Li: Conceptualization, Supervision, Writing – review \u0026amp; editing, Project administration.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eTeo ZL, Tham YC, Yu M, Chee ML, Rim TH, Cheung N, Bikbov MM, Wang YX, Tang Y, Lu Y\u003cem\u003e et al\u003c/em\u003e: \u003cstrong\u003eGlobal Prevalence of Diabetic Retinopathy and Projection of Burden through 2045: Systematic Review and Meta-analysis\u003c/strong\u003e. \u003cem\u003eOphthalmology \u003c/em\u003e2021, 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MM, Shah GK, Sharma SM: \u003cstrong\u003eThe cost-effectiveness of early vitrectomy for the treatment of vitreous hemorrhage in diabetic retinopathy\u003c/strong\u003e. \u003cem\u003eCurr Opin Ophthalmol \u003c/em\u003e2001, \u003cstrong\u003e12\u003c/strong\u003e(3):230\u0026ndash;234.\u003c/li\u003e\n\u003cli\u003eGuo H, Li W, Wang K, Nie Z, Zhang X, Bai S, Duan N, Li X, Hu B: \u003cstrong\u003eAnalysis of Risk Factors for Revitrectomy in Eyes with Diabetic Vitreous Hemorrhage\u003c/strong\u003e. \u003cem\u003eDiabetes Metab Syndr Obes \u003c/em\u003e2023, \u003cstrong\u003e16\u003c/strong\u003e:2865\u0026ndash;2874.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"international-journal-of-retina-and-vitreous","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"IJRV","sideBox":"Learn more about [International Journal of Retina and Vitreous](https://jneurodevdisorders.biomedcentral.com/)","snPcode":"40942","submissionUrl":"https://submission.nature.com/new-submission/40942/3","title":"International Journal of Retina and Vitreous","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Proliferative diabetic retinopathy, Vitreous hemorrhage, Anti-VEGF, Reoperation, Survival analysis, Surgical burden","lastPublishedDoi":"10.21203/rs.3.rs-9117069/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9117069/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cb\u003ePurpose\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTo investigate the long-term risk factors for post-operative vitreous hemorrhage (VH) within 24 months following vitrectomy for proliferative diabetic retinopathy (PDR), evaluate the protective efficacy of preoperative anti-VEGF therapy, and quantify the associated secondary surgical burden.\u003c/p\u003e\u003cp\u003e\u003cb\u003eMethods\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThis retrospective cohort study included 735 eyes from 735 PDR patients. A 24-month survival analysis was employed to categorize patients into VH (n\u0026thinsp;=\u0026thinsp;179) and non-VH (n\u0026thinsp;=\u0026thinsp;556) groups. Independent predictors were identified using univariate and multivariate Cox proportional hazards models. A sensitivity analysis was performed on a \"pure hemorrhage model\" (n\u0026thinsp;=\u0026thinsp;676) by excluding eyes with post-operative tractional retinal detachment (TRD) to isolate the direct vascular-stabilizing effect of anti-VEGF.\u003c/p\u003e\u003cp\u003e\u003cb\u003eResults\u003c/b\u003e\u003c/p\u003e \u003cp\u003eThe overall cumulative incidence of post-operative VH was 18.4% at 12 months and 25.7% at 24 months. Multivariate Cox analysis revealed that preoperative anti-VEGF injection was the most potent protective factor, associated with a 63% reduction in VH hazard (HR 0.37; 95% CI, 0.27\u0026ndash;0.51; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). This protective effect remained robust in the sensitivity analysis (HR 0.32; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001), indicating a direct vascular stabilization independent of anatomical success. Independent risk factors included severe fibrovascular traction (HR 1.93; P\u0026thinsp;=\u0026thinsp;0.003), younger age, higher HbA1c, and elevated serum creatinine (all P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Patients in the VH group had significantly poorer final visual outcomes (1.33\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75 vs. 0.92\u0026thinsp;\u0026plusmn;\u0026thinsp;0.60 LogMAR; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and a markedly higher reoperation rate (31.3% vs. 7.2%). Notably, hemorrhage-related indications accounted for 58.4% of the total secondary surgical workload.\u003c/p\u003e\u003cp\u003e\u003cb\u003eConclusion\u003c/b\u003e\u003c/p\u003e \u003cp\u003ePost-operative VH is a dominant driver of long-term visual impairment and secondary surgical burden in PDR. Preoperative anti-VEGF confers a direct, sustained protective effect by stabilizing the retinal microvasculature. Effective prevention of VH could potentially eliminate nearly 60% of the reoperation requirements in this population.\u003c/p\u003e","manuscriptTitle":"Preoperative Anti-VEGF and the Cumulative Risk of Post-operative Vitreous Hemorrhage in PDR: A 2-Year Survival Analysis and Evaluation of Surgical Burden","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-24 16:54:58","doi":"10.21203/rs.3.rs-9117069/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-22T01:19:23+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T11:17:02+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-07T09:27:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"133528292308960279029206196072677758725","date":"2026-04-05T01:55:17+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"32510383923418458429573618294956843247","date":"2026-04-04T15:15:18+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"210554915795081404668546172921466661528","date":"2026-04-04T07:20:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"202978682840041312681920832484358635986","date":"2026-04-04T04:05:57+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-19T03:57:48+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-19T03:28:57+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-18T16:48:27+00:00","index":"","fulltext":""},{"type":"submitted","content":"International Journal of Retina and Vitreous","date":"2026-03-13T17:17:15+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"international-journal-of-retina-and-vitreous","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"IJRV","sideBox":"Learn more about [International Journal of Retina and Vitreous](https://jneurodevdisorders.biomedcentral.com/)","snPcode":"40942","submissionUrl":"https://submission.nature.com/new-submission/40942/3","title":"International Journal of Retina and Vitreous","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"85fed5e4-4f4b-41b9-8359-b133b710ab5a","owner":[],"postedDate":"March 24th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-16T18:23:17+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-24 16:54:58","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9117069","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9117069","identity":"rs-9117069","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}