Postoperative Complications of Pars Plana Vitrectomy for Diabetic Retinal Disease

The effect of adjuvant Mitomycin C during vitrectomy on functional and anatomical outcomes in patients with severe diabetic tractional retinal detachment

PURPOSE

To evaluate the effect of adjuvant Mitomycin C (MMC) use on the anatomical and functional success of vitreoretinal surgery (VRS) in severe diabetic tractional retinal detachment (dTRD) patients.

METHODS

A retrospective analysis of consecutive patients undergoing VRS due to severe dTRD was conducted. Patients were categorized into those who received 20 µg/0.1 mL MMC via MMC sandwich method (Group 1) and those who did not (Group 2). Demographics, surgical characteristics, visual outcomes, and complications that may related to MMC were analyzed.

RESULTS

A total of 25 eyes were included, 13 in Group 1 and 12 in Group 2. No statistical difference was observed in baseline characteristics between the groups. The mean best-corrected visual acuity was 1.90 ± 0.43 logMAR and 1.93 ± 0.41 logMAR preoperatively and 1.60 ± 0.78 logMAR and 1.56 ± 0.78 logMAR postoperatively in Groups 1 and 2, respectively (p = 0.154). The postoperative mean intraocular pressure was 16.23 ± 2.55 mmHg and 13.08 ± 4.94 mmHg in Groups 1 and 2, respectively (p = 0.225). The rate of re-surgery was significantly lower in Group 1 (0% vs. 41.7% in Group 2, p = 0.015). Retina was attached in all patients at the last visit. No MMC-related complication was recorded.

CONCLUSION

Intraoperative adjuvant MMC application for severe dTRD significantly reduces re-surgery rates with good anatomical and functional outcomes safely.

Outcomes of intravitreal anti-VEGF injections and panretinal photocoagulation in preretinal hemorrhage secondary to proliferative diabetic retinopathy involving the fovea

PURPOSE

To evaluate the outcome of intravitreal anti-vascular endothelial growth factor (VEGF) injections and panretinal photocoagulation (PRP) in fovea involving preretinal hemorrhage (PRH) secondary to proliferative diabetic retinopathy (PDR).

METHODS

Retrospective non-comparative cross-sectional series of patients diagnosed with fovea involving PRH secondary to PDR at our institute from March 2019 to October 2021 who were treated with combination treatments of intravitreal anti-VEGF and PRP and have completed a minimum 6-month follow-up. The primary outcome measure was serial changes in the visual acuity (VA) and PRH regression from the fovea. Secondary outcome measures were the quantitative assessment of the size of PRH, its association with VA improvement and time to regression, and the proportion of patients who underwent surgery for poor response.

RESULTS

In total, 22 eyes of 21 patients showed regression of PRH from the foveal center at 33.6 days, and complete regression was seen at 140.7 days. The average number of anti-VEGF injections required for clearance of PRH from the fovea was 1.6. Mean LogMAR visual acuity improved from 0.54 at baseline to 0.32 at 4 weeks and 0.18 at 6 months ( P < 0.01). Three eyes (13.6%) required vitrectomy surgery during follow-up. The mean area of PRH as measured by Image J analysis was 14.78 mm 2 at baseline, 8.97 mm 2 at 4 weeks, and 1.25 mm 2 at 3 months ( P < 0.01). No statistically significant difference was seen between the size of PRH and PRH clearance time and VA improvement. No systemic side effects were observed following the intravitreal injections during follow-up.

CONCLUSION

Intravitreal anti-VEGF injections and PRP were found to be effective and safe treatment methods for fovea involving PRH secondary to PDR. Long-term studies are warranted to assess the long-term efficacy.

Preoperative Visual Acuity Thresholds in Pars Plana Vitrectomy for Epiretinal Membrane: A Systematic Review

BACKGROUND AND OBJECTIVE

This review consolidates findings from studies that used a preoperative visual acuity (VA) threshold as an indication for epiretinal membrane (ERM) surgery.

METHODS

The literature was systematically searched using Ovid MEDLINE, EMBASE, and Cochrane Library from January 2000 to October 2022 to select studies reporting on pars plana vitrectomy (PPV) for ERM that used a preoperative VA threshold as an inclusion criterion. Primary outcomes were final best-corrected visual acuity (BCVA) and change in BCVA relative to baseline. Secondary outcomes included risk of intra- and postoperative complications.

RESULTS

A total of 639 eyes from seven studies were included. The most liberal preoperative VA threshold was 20/28.5 or worse, whereas the most conservative threshold was worse than 20/60. The mean preoperative BCVA was 0.55 logarithm of the minimum angle of resolution (logMAR) (∼20/70), and the mean postoperative BCVA was 0.35 logMAR (∼20/45). Generally, VA improved relative to baseline, regardless of the preoperative VA threshold. The smallest improvement in VA was observed in a study where the pre-operative VA to consider surgery was liberal (20/30 or worse), whereas the greatest VA improvement was observed in a study that used a conservative preoperative VA threshold (worse than 20/60).

CONCLUSIONS

The greatest improvement in BCVA was observed in studies where a conservative pre-operative VA threshold was used. The decision to operate should involve a patient-centered approach with a thorough discussion of the risks and benefits of PPV, regardless of the preoperative VA threshold used. [Ophthalmic Surg Lasers Imaging Retina 2024;55:xx-xx.].

VITRECTOMY FOR VITREOUS HEMORRHAGE ASSOCIATED WITH RETINAL VEIN OCCLUSION: Visual Outcomes, Prognostic Factors, and Sequelae

PURPOSE

To report the outcomes of pars plana vitrectomy for vitreous hemorrhage (VH) associated with retinal vein occlusion and to identify prognostic indicators.

METHODS

Interventional, retrospective consecutive case series between 2015 and 2021.

RESULTS

The study included 138 eyes of 138 patients (64 female and 74 male); 81 patients had branch retinal vein occlusion and 57 had central retinal vein occlusion. The mean age was 69.8 years. The mean duration between the diagnosis of VH and surgery was 79.6 ± 115.3 (range, 1-572) days. The mean follow-up was 27.2 months. The logarithm of the minimum angle of resolution visual acuity significantly improved from 1.95 ± 0.72 (Snellen equivalent, 20/1782) to 0.99 ± 0.87 (20/195) at 6 months and to 1.06 ± 0.96 (20/230) at the final visit (both P < 0.001). The visual acuity at 6 months improved by three or more lines in 103 eyes (75%). Postoperative complications during follow-up included recurrent VH in 16 eyes (12%) (of which 8 eyes underwent reoperations), rhegmatogenous retinal detachment in six eyes (4%), and new neovascular glaucoma in three eyes (2%). Worse final visual acuity was significantly associated with older age ( P = 0.007), concurrent neovascular glaucoma ( P < 0.001), central retinal vein occlusion ( P < 0.001), worse preoperative visual acuity ( P < 0.001), postoperative new neovascular glaucoma ( P = 0.021), and postoperative retinal detachment ( P < 0.001). The duration of VH was not associated with visual outcomes ( P = 0.684). Preoperative antivascular endothelial growth factor injections and tamponade did not prevent postoperative recurrent VH.

CONCLUSION

Pars plana vitrectomy is effective for VH associated with retinal vein occlusion, regardless of the duration of hemorrhage. However, pre-existing risk factors and postoperative sequelae may limit visual recovery.

Factors related to postoperative vitreous hemorrhage after small-gauge vitrectomy in proliferative diabetic retinopathy patients

BACKGROUND

The role of anticoagulation or antiplatelet on post-vitrectomy vitreous hemorrhage (POVH) in patients with proliferative diabetic retinopathy (PDR) is rarely investigated in the small-gauge vitrectomy era. We investigate the relationship between the long-term use of those medications and POVH in a group of PDR patients.

METHODS

A retrospective cohort study was carried out in a group of PDR patients who underwent small-gauge vitrectomy in our center. The baseline data on diabetes, diabetic complications, long-term use of anticoagulants and antiplatelet agents, ocular findings, and vitrectomy details were collected. The occurrence of POVH was recorded during at least three-month follow-up. Factors related to POVH were analyzed using logistic analysis.

RESULTS

During a median follow-up of 16 weeks, 5% (11/220) of patients had POVH, and 75 had received antiplatelet or anticoagulation agents before the operation. Factors related to persistent POVH were the use of antiplatelet or anticoagulation agents (5.98, 1.75-20.45, p = 0.004), the presence of myocardial revascularization (130.65, 3.53-4834.50, p = 0.008), the presence of coronary artery disease (CAD) treated with medicine (56.52, 1.99-1604.06, p = 0.018), and younger age (0.86, 0.77-0.96, p = 0.012). For those receiving preoperative antiplatelet or anticoagulation agents, the probability of developing POVH was higher in the patients whose previous therapy was adjusted compared to those with continued therapy (p = 0.02 by Log-rank test).

CONCLUSIONS

We identified long-term use of anticoagulation or antiplatelet medication, the presence of CAD, and younger age as three independent factors related to POVH. In PDR patients on long-term antiplatelet or anticoagulation medications, particular attention should be given to controlling intraoperative bleeding, and follow-up for POVH should be scheduled.

Risk Factors for Recurrent Vitreous Hemorrhage in Type 2 Diabetes Mellitus Patients after Posterior Vitrectomy

(Background) The aim of this study was to determine the factors related to recurrent vitreous hemorrhage (RVH) in a sample of proliferative diabetic retinopathy (PDR) patients. (Methods) This was a retrospective, review-based study. We studied 183 eyes from 121 type 2 diabetes patients with PDR. We recorded the duration of diabetes, history of hypertension, retinal photocoagulation status, posterior vitreous status, mean HbA1c and hemoglobin levels, renal function, and systemic complications associated with diabetes. We also recorded surgical variables-the presence of tractional retinal detachment, the application of segmentation and diathermy on fibrovascular proliferative tissue, and the use of silicone oil-to study which independent variables were significantly related to the presence of RVH. (Results) The duration of diabetes (p = 0.028), hemoglobin level (p = 0.02), status of the posterior vitreous (p = 0.03), retinal photocoagulation status (p = 0.002), and the presence of tractional retinal detachment (p = 0.03) were significantly associated with the presence of RVH. On the other hand, the use of diathermy was associated with fewer RVH events (p < 0.005). In addition, patients with diabetic polyneuropathy, myocardial infarction, and ischemia in the lower limbs exhibited more vitreous hemorrhage events (p < 0.001). (Conclusions) Patients with PDR and a longer diabetes duration, anemia, attached posterior vitreous, deficient retinal photocoagulation, and prior cardiovascular events were more prone to RVH.

A New Pharmacological Vitreolysis through the Supplement of Mixed Fruit Enzymes for Patients with Ocular Floaters or Vitreous Hemorrhage-Induced Floaters

Purpose: Ocular floaters caused by vitreous degeneration or blood clots may interfere with various visual functions. Our study investigated the pharmacologic effects of oral supplementation of mixed fruit enzymes (MFEs) for treating spontaneous symptomatic vitreous opacities (SVOs) and those secondary to vitreous hemorrhage (VH). Methods: 224 patients with monocular symptomatic vitreous opacities (SVOs) were recruited between September and December 2017 and received oral supplementation of MFEs (190 mg bromelain, 95 mg papain, and 95 mg ficin) for 3 months in a double-blind clinical trial. Participants were divided according to the etiology of the SVOs, spontaneous (experiment 1) versus VH (experiment 2), and then randomly assigned into four treatments groups: one group received oral vitamin C, as a placebo; and the other 3 groups received 1 capsule per day (low dose), 2 capsules per day (middle dose), or 3 capsules per day (high dose) of MFEs. The number of SVOs was determined at baseline and then 1, 2, and 3 months after initiating treatment. Further, in cases secondary to VH, the changes in corrected distance visual acuity (CDVA) were assessed after 3 months. Second, we compared the free radical scavenging capabilities of each substance: vitamin C, bromelain, papain, ficin, and MFEs (combination of bromelain, papain, and ficin) by DDPH assay. Finally, SVOs-related symptoms and satisfaction with the treatments were evaluated at the last follow-up visit Results: In experiment 1, the disappearance rate of SVOs was 55%, 62.5%, and 70% after taking 1, 2, and 3 capsules daily, respectively (total p < 0.001), in a dose-dependent manner. In experiment 2, the disappearance rate of VH-induced SVOs was 18%, 25%, and 56% (p < 0.001) after 1, 2, and 3 capsules of the supplement daily, respectively. Additionally, the patients’ vision elevated from 0.63LogMAR to 0.19LogMAR (p = 0.008). Conclusions: A pharmacological approach using a high dose of oral supplementation with MFEs (bromelain, papain, and ficin) was effective in reducing vitreous opacities, even after intraocular hemorrhage. Furthermore, pharmacologic vitreolysis with MFEs supplementation showed high patient satisfaction, and also improved CDVA in patients with vitreous hemorrhage-induced floaters

Protocol to quantify enzymatic effects on vitreous liquefaction in porcine eyes using a transwell-plate system

This protocol describes an ex vivo model to quantify enzymatic effects on vitreous liquefaction using porcine eyes in a transwell-plate system via induced syneresis. It provides a standardized dissection process and performs critical steps for gel-liquid separation with high precision, minimal tissue loss, and scalability. The protocol can be applied to other studies investigating vitreous liquefaction or gelatinous tissue analysis and can also serve to study vitreous liquefaction in vivo as it may occur during aging or disease progression.

Safety and effectiveness of an iris hook assisted phacoemulsification in vitrectomized eyes

AIM

To introduce a simple iris hook assisted phacoemulsification (PE) procedure and evaluate the safety and efficacy of it in completely vitrectomized eyes.

METHODS

A single centre study which included 65 previously completely vitrectomized eyes of 62 patients who underwent cataract surgery. Patients were randomly divided into 3 groups. Patients received PE, and intraocular lens (IOL) implantation with the assistance of iris hook (Synergeties™) as group A (25 eyes); patients who received PE assisted with a 25G pars plana irrigation as group B (20 eyes), and patients who received PE performed without the help of any instrument as group C (20 eyes). Main outcome measures were surgery duration, Ultrasound (U/S) total time, endothelial cell density (ECD), cumulative dissipated energy (CDE) and complications of the procedures.

RESULTS

With the help of iris hook, the patients in group A had the lowest ECD loss rate (0.07±0.03, 0.09±0.03, and 0.10±0.03, P<0.05), shortest CDE (12.2±4.1, 15.8±6.0, and 16.0±6.0, P<0.05) and U/S total time (36.6±13.0s, 46.3±16.4s, and 47.6±16.1s, P<0.05), and minimal incidence of complications. The longest surgery duration was in group B (19.4±1.6min) and maximum complications rate in group C (20% miosis, 10% posterior capsular tears, 5% zonular dialysis, 5% cystoid macular edema). While best-corrected visual acuity (BCVA), intraocular pressure (IOP) and ECD did not show a significant difference among the three groups.

CONCLUSION

Without prolonged surgery duration, the iris hook assistant method can minimize heat generation during surgery and incidence of complications, which transfer the challenged PE in vitrectomized eyes into a regular surgery. It does not need any change in the hydrodynamic parameters and in the bag PE technique, easy to operate even for junior surgeons.

Incidence of and Risk Factors for Postoperative Hyphema After 23-Gauge Pars Plana Vitrectomy for Proliferative Diabetic Retinopathy

Purpose

We aim to investigate the incidence, clinical course, and risk factors for developing postoperative hyphema after 23-gauge pars plana vitrectomy (PPV) for patients with proliferative diabetic retinopathy (PDR) without neovascularization of the iris or angles and neovascular glaucoma (NVG).

Methods

This retrospective study included 155 consecutive eyes from 124 patients with at least three-month follow-up who underwent PPV for PDR without neovascularization of the iris or angles and NVG. Demographic data, surgery notes, postoperative hyphema assessment, intraocular pressure (IOP), and the surgical outcome were recorded.

Results

Postoperative hyphema occurred in 18 of 155 eyes (11.6%), with 14 of those having hyphema on day 1, and 4 having hyphema on days 7–20. Of the 18 eyes, only 3 (16.7%) had normal IOP, and immediate intraocular hypertension was observed in 15 (83.3%). Seven eyes required anterior chamber paracentesis and five needed anterior chamber irrigation. The average time for absorption of the hyphema was 13.1 days, and IOP was controlled in all cases. There was a significant correlation between membrane removal and the development of hyphema (OR = 5.65 and 95% CI: 1.190–25.203; p = 0.013). No recurrence of hyphema was observed. In patients with hyphema, the final best corrected visual acuity (BCVA) was 1.75 ± 0.84 logMAR, which improved significantly compared to the initial BCVA of 2.20 ± 0.65 logMAR (t = 3.893; p = 0.001), and the final anatomic success rate was 100%.

Conclusion

The development of hyphema is not uncommon after PPV for patients with PDR without neovascularization of the iris or angles and NVG, and membrane removal is a risk factor for postoperative hyphema. The timely management of hyphema ensures that hyphema does not affect the visual recovery or the final anatomical success.

Tandem mass tag-based proteomic analysis reveals cathepsin-mediated anti-autophagic and pro-apoptotic effects under proliferative diabetic retinopathy

Proliferative diabetic retinopathy (PDR) is a severe complication of diabetes and can cause blindness. However, the available therapeutic modalities to PDR have unsatisfactory efficacies and incur adverse effects, which is due to the paucity in the understanding of pathogenic mechanisms responsible for the disease. In this study, tandem mass tag labeling technology combined with liquid chromatography and tandem mass spectrometry were utilized to identify differentially expressed proteins in vitreous humor of patients with rhegmatogenous retinal detachment and PDR. The data are available via ProteomeXchange with identifier PXD021788. Afterwards, the downregulated protein expression of Cathepsin B, D, and L was verified in vitreous and serum of another cohort. The gene expression profiling of the 3 cathepsins was confirmed in blood cells of an extra cohort. Furthermore, in high glucose (HG)-treated retinal vascular endothelial cell cultures recapitulating the cathepsin expression patterns, Cathepsin B or D downregulation mediated the HG-induced anti-autophagic and pro-apoptotic effects, thereby may contribute to vascular lesions under hyperglycemia. This study demonstrates previously undescribed expression patterns of cathepsins, reveals a novel cathepsin-involved pathogenic mechanism under PDR, and sheds light on potential therapeutic targets to this debilitating retinal disease.

Recurrent retinal detachment after diabetic vitrectomy

PURPOSE

To investigate the characteristics of recurrent retinal detachment (RD) after diabetic vitrectomy (DV).

METHODS

Consecutive cases underwent vitrectomy for recurrent RD after DV was collected and separated into the following four groups for analysis: rhegmatogenous RD (RRD), pure tractional RD (Proliferative Subgroup 1), combined RD with proliferative tissue within the equator (Proliferative Subgroup 2), and combined RD with both posterior and peripheral proliferations (Proliferative Subgroup 3).

RESULTS

Of the 41 cases enrolled, retinal reattachment was achieved in 73.2%. Over all, visual acuity was statistically better after operation (p = 0.001). All cases in the RRD group (four cases) had reattachment and a better final vision (p = 0.008). In the proliferative subgroups, those with pure tractional RD (Subgroup 1, seven cases) had the best visual acuity at the time of recurrent RD (p = 0.002). Subgroups 2 and 3 showed statistically significant better final visual acuity (p = 0.045 and 0.019, respectively). Poor preoperative vision (p = 0.001), non-attachment (p = 0.004), and neovascular glaucoma (p = 0.001) were associated with poor prognosis.

CONCLUSIONS

Visual acuity may improve after operation for recurrent RD after diabetic vitrectomy. Visual prognosis was better in cases with pure RRD. In the proliferative subgroups, vision was impaired by the development of neovascular glaucoma and retinal non-attachment.

Change of Vascular Endothelial Growth Factor Levels following Vitrectomy in Eyes with Proliferative Diabetic Retinopathy

Purpose

To study the change of concentrations of vascular endothelial growth factor (VEGF) in vitreous cavity after vitrectomy in eyes with proliferative diabetic retinopathy (PDR).

Methods

In this retrospective study, intravitreal fluid samples were taken at baseline (beginning of the vitrectomy) and postoperatively (several days later after vitrectomy) at the time of prophylactic injection of bevacizumab in forty-eight eyes of forty-eight patients with PDR. Postvitrectomy fluid samples were divided into four groups according to the time interval between the vitrectomy and the injection (group 1, 3–5 days; group 2, 6–10 days; group 3, 11–15 days; group 4, 16–21 days; twelve eyes in each group). Postvitrectomy fluid sample was paired with baseline sample for each eye. VEGF concentrations in the samples were determined by enzyme-linked immunosorbent assay. Recurrent vitreous hemorrhage and neovascular glaucoma within six months postvitrectomy were also analyzed.

Results

Overall, the intravitreal VEGF level after vitrectomy (median, 36.95 pg/ml; range, 3.2–1,299.4 pg/ml) was significantly less than the VEGF level at baseline (median, 704.5 pg/ml; range, 30.6–1,981.1 pg/ml). Postoperative and baseline VEGF levels were significantly correlated (r = 0.499, p < 0.01). Both the absolute value of postoperative VEGF concentrations and the postop/baseline VEGF ratios declined with time and dramatically decreased in groups 3 and 4. In only two eyes, the postoperative VEGF level was even higher than the baseline VEGF level (postop/baseline VEGF ratio >1), and recurrent vitreous hemorrhage developed within six months in these two eyes.

Conclusions

After vitrectomy for PDR, intravitreal VEGF levels decreased substantially in the majority of patients, while persistent high-VEGF level occurred in a few individuals. Postoperative VEGF levels and postop/baseline VEGF ratio declined with time. The postop/preop VEGF ratio may serve as a predictor for late complications.

Preoperative albumin-to-fibrinogen ratio predicts severe postoperative complications in elderly gastric cancer subjects after radical laparoscopic gastrectomy

BACKGROUND

A high prevalence of postoperative complications is closely associated with a worse short- and long-term outcome. This current study aimed to investigate potential risk factors including albumin-to-fibrinogen ratio (AFR) for severe postoperative complications (SPCs) in surgical gastric cancer (GC) patients.

METHODS

Elderly patients (≥65 years) with primary GC who underwent elective radical laparoscopic gastrectomy under general anesthesia were included. According to the Clavien-Dindo classification system, the severity of complications was assessed from Grade I to V and SPCs were defined as C-D Grade ≥ IIIa. The clinicopathological features, operative-associated characteristics, postoperative recovery and laboratory tests were compared between patients with or without SPCs. Receiver operating characteristic (ROC) curve analysis using Youden's Index was established for determining the predictive value and cut-off threshold of AFR for SPCs. Binary univariate and multivariate logistic regression models were used to assess factors influencing SPCs.

RESULTS

A total of 365 elderly GC patients were finally included in the analysis, of which 52 (52/365, 14.2%) patients had developed SPCs within postoperative 30 days. Preoperative AFR level predicted SPCs in surgical GC patients with an AUC of 0.841, a sensitivity of 76.36% and a specificity of 80.77%, respectively (P < 0.001). The multivariate analysis revealed that a lower AFR level (OR: 1.94, 95% CI: 1.09-3.36, P = 0.017) and an older age (OR: 1.81, 95% CI: 1.06-3.04, P = 0.023) were two independent predictive factors for SPCs in surgical GC patients.

CONCLUSIONS

Preoperative AFR level is a useful predictor for SPCs in elderly GC subjects after radical laparoscopic gastrectomy.