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Background: To investigate the presence of silicone oil (SO)-emulsification on the anterior iris surface with anterior segment optical coherence tomography (AS-OCT)., Methods: In this single-center cross-sectional study, vitrectomized eyes with SO tamponade that underwent AS-OCT imaging and gonioscopy examination during the postoperative follow-up visits, were reviewed., Results: 45 eyes of 42 consecutive patients were included. In 35.6% of the eyes (n = 16) emulsified SO droplets were detected in the anterior chamber (AC) angle by gonioscopy and in 55.6% (n = 25) on the anterior iris surface by AS-OCT imaging. The presence of SO emulsifications in the AC-angle correlated with the presence of SO emulsifications on the anterior iris surface (OR = 13.4, 95% CI [2.179-82.130]; p = 0.005). The accuracy of the AS-OCT predicting the presence of SO in the AC-angle was 71.0% and the sensitivity was 87.5%. No significant association between SO droplets in the AC and other clinical parameters including endotamponade-duration or type of silicone oil were found. The presence of emulsified SO droplets on the anterior iris surface detected by AS-OCT was significantly correlated to postoperative IOP rise (p = 0.027)., Conclusion: AS-OCT is a suitable method for the detection of SO on the anterior iris surface. SO droplets on the iris surface correlate with elevated postoperative IOP and with the presence of SO in the AC detected by gonioscopy, therefore AS-OCT might be used as a screening method for the detection of SO migration into the AC., Trial Registration Number: Institutional Review Board of the Hamburg Medical Chamber (Ethik-Kommission der Ärztekammer Hamburg): 2023-300372-WF., (© 2024. The Author(s).)

Purpose: To propose the InTraocular EMulsion of Silicone oil (ITEMS) grading system for the assessment of silicone oil (SiO) emulsion, applicable in a routine clinical setting and validated through an expert-led consensus procedure., Methods: Seven experts on intraocular liquid tamponades, led by a facilitator, performed a literature review on the detection of SiO emulsion. Based on the proposed ideas, a questionnaire was developed and submitted to the experts on the methods to detect SiO emulsion and the items to grade. After 2 rounds of individual ranking using a 9-point scale and related discussion, the final grading system was developed including items that reached consensus (score ≥7 from ≥75% of members)., Results: The agreed ITEMS grading system includes the identification of SiO microbubbles and large SiO bubbles through slit-lamp biomicroscopy, gonioscopy, fundus examination under mydriasis, or ultra-wide-field fundus photography. Moreover, macular and disk optical coherence tomography are used to detect SiO-associated hyperreflective dots., Conclusion: An evidence-based expert-led consensus was conducted to develop grading system of SiO emulsion, allowing, for the first time, homogenous collection of data on SiO emulsion. This has the potential to improve the understanding of the role and clinical relevance of SiO emulsion, allowing comparisons between different studies.

Purpose: Lens opacification is a common complication after pars plana vitrectomy (PPV) and knowing its progression would facilitate consulting patients. The purpose of this study was to evaluate a quantitative model for lens-status-monitoring after PPV with C3F8 gas. Our model was evaluated in rhegmatogenous retinal detachment (RRD) patients of various age and lens densitometry (LD)., Methods: Data between March 2018 and March 2020 were evaluated retrospectively. LD measurements of the PentacamHR® Nucleus Staging mode (PNS) were used to quantify lens opacification over time. A mixed-effect regression model was designed, to enable LD predictions at any time postoperatively. Calculations were based on patient's age and baseline LD as dependent variables. Six patients were randomly excluded during model development, to be used for testing its power afterwards., Results: 34 patients (male 19 [55.9%], female 15 [44.1%]) matched the inclusion criteria. Average age was 58.5 years (32-77;±4.3) and average follow-up was 7.2 months (3,4-23.1;±1,8). Mean baseline LD of the treated and fellow eye before surgery were 10.9% (8.7%-14.8%;±0.8) and 10.7% (8.5%-14.1%;±0.6), respectively. Using our prediction model, LD values for the six pre-selected patients closely match the observed data with an average deviation of 1.07%., Conclusions: Evaluation of age and baseline LD using a mixed-effect regression model might predict cataract progression in RRD patients treated with PPV and C3F8-gas. Such a tool could be considered during cataract surgery consultation in these patients., Competing Interests: The authors have declared that no competing interests exist.

Introduction: Idiopathic epiretinal membrane (ERM) is a proliferation of cells formed on the internal surface of the retina and may cause a slow decrease in visual acuity (VA). The aim of this study was to evaluate the individual layers of the retina by optical coherence tomography (OCT) before and after vitrectomy with ERM peeling in order to refine surgical decision-making., Methods: Forty-seven eyes of 45 patients (aged 55-87 years) with ERM were enrolled retrospectively from a tertiary referral center. OCT examination was performed preoperatively and at a mean of 3.2 months postoperatively in all cases. Nine retinal surfaces were subjected to automated all-layer segmentation using the manufacturer's software and assessed for their correlation with VA., Results: There was a significant correlation between the initial retinal morphology and change in VA postoperatively. Patients who gained at least two lines of VA had a significantly higher total retinal perimacular volume and retinal nerve fiber layer (each p < 0.0001) preoperatively., Conclusion: Patients with high preoperative retinal volumes and therefore increased tractive components seemed to benefit more from surgery than those with low tractive components.

Purpose: The aim of this study was to characterize a standardized porcine ex-vivo testing system for intraocular pressure (IOP) monitoring after vitrectomy with different endotamponades., Methods: Twenty-four pig eyes, six per endotamponade group were obtained immediately postmortem. After pars plana vitrectomy, vitreous substitutes (silicone oil 1000 mPas, 2000 mPas, 5000 mPas, and Balanced Salt Solution (BSS)) were instillated and IOP was observed over 24-hours. Infusion pumps with Dulbecco's Modified Eagle Medium (DMEM) simulated a constant aqueous humor circulation. A histological examination of the trabecular meshwork with DAPI- and TUNEL-staining was performed to detect the amount of apoptotic cells., Results: TUNEL-assay showed a mean cell death rate of 3.78% (SD ± 1.46%) for silicone oil endotamponades compared to 5.05% (SD ± 2.18%) in BSS group. One-way ANOVA (p = 0.425) showed no significant difference between both groups. Mean IOP in silicone oil endotamponades was 9.50 mmHg (SD ± 1.68 mmHg) at baseline, 13.23 mmHg (SD ± 0.79 mmHg) after 1 hour, 18.46 mmHg (SD ± 2.13 mmHg) after 12 hours and 15.51 mmHg (SD ± 2.82 mmHg) 24 hours after instillation. A comparison of all silicone oil groups (one-way ANOVA, Bonferroni post-hoc test, p = 0.269 to 1.000) didn't reveal significant differences in mean IOP., Conclusion: The standardized ex-vivo porcine model represents an effective alternative to the in-vivo testing in animals. Maintaining the trabecular and uveoscleral outflow pathway enables a pseudo in-vivo analysis.

Purpose: To report the outcomes of primary transconjunctival 23-gauge (23-G) vitrectomy in the diagnosis and treatment of presumed endogenous fungal endophthalmitis (EFE)., Methods: Retrospective analysis of patients with EFE who underwent diagnostic transconjunctival 23-G vitrectomy at a tertiary referral center., Results: Nineteen eyes of 15 patients with EFE were included in the study. Four patients had bilateral and 11 patients unilateral disease. Sixteen eyes of 15 patients underwent 23-G vitrectomy to confirm the diagnosis using vitreous culture, polymerase chain reaction, and histopathologic examinations. All affected eyes were treated with intravitreal amphotericin B 5 µg/0.1 mL. Fourteen patients received additional systemic antifungal therapy. Diagnostic 23-G vitrectomy confirmed the diagnosis of EFE in 75% of the eyes (12/16). Candida was found to be a causative agent in 62.5% and Aspergillus in 12.5% of the eyes. Retinal detachment was the most common complication (42% of eyes)., Conclusions: EFE can be easily confirmed using primary 23-G vitrectomy.

Purpose: Several iatrogenic risk factors during pars plana vitrectomy (PPV) could cause damage to the retina. One mechanism is excitotoxicity. Therefore, neuroprotective irrigation solutions would be desirable., Methods: Retinal ganglion cells (RGC-5) and retinal whole mounts were incubated in standard irrigation solution (SIS) and Dulbecco's Modified Eagle Medium (DMEM). Cell viability, cell amount, cell survival and caspase 3/7 activity were measured by MTS-Test, crystal-violet staining, Annexin-V/PI flow cytometry and caspase 3/7 activity assay, respectively. The morphology and the function of retinal whole mounts were analysed by Live/Dead(TM) staining and by the b-wave and a-wave of the electroretinogram (ERG)., Results: Under excitotoxic conditions (10 mM and 12 mM glutamate) RGC-5 cells incubated in SIS showed a statistically significant reduction in cell viability, cell amount, cell survival and caspase 3/7 activity compared to DMEM. Furthermore, the incubation of retinal whole mounts in DMEM resulted in a significant decrease of cell death under excitotoxic (250 μM glutamate) and standard conditions compared to SIS. ERG b-wave recordings revealed good functional preservation of retinal whole mounts in DMEM, but loss in SIS., Conclusion: DMEM seems to support retinal cells very well and to be strongly protective against excitotoxicity. Therefore, DMEM may be considered as possible neuroprotective irrigation solution for PPV.

Background: During pars plana vitrectomy, the retina is exposed to several iatrogenic risk factors, including excitotoxicity. A taurine-containing irrigation solution for pars plana vitrectomy (PURI PROTECT) has been developed and is claimed to have neuroprotective properties., Methods: Retinal ganglion cells (RGC-5) and retinal whole mounts were incubated in standard irrigation solution (SIS) and SIS supplemented with 3 mM taurine (SIS-taurine). Excitotoxicity was induced by the addition of 8, 10, and 12 mM or 250 μM glutamate. Cell viability and cell survival were assessed by the MTT test and Annexin-V/propidium iodide flow cytometry. Whole mounts were stained with the Live/Dead staining assay. Pars plana vitrectomy with SIS or SIS-taurine was performed in rabbits. Animals were followed-up by electroretinography., Results: RGC-5 incubated in SIS-taurine showed a 4.3-fold (P < 0.0005) better overall cell viability and an up to 8.5-fold (P < 0.05) increased cell survival under excitotoxic conditions compared with that incubated in SIS. Whole mounts incubated in SIS-taurine showed a 1.7-fold (P < 0.0005) and 1.6-fold (P < 0.0005) better cell survival under excitotoxic and nonexcitotoxic conditions, respectively. In the immediate postoperative period, b-wave amplitudes were significantly better in animals operated with SIS-taurine compared with control (P < 0.01)., Conclusion: A taurine-containing irrigation solution may protect retinal ganglion cells against excitotoxicity.

Despite major improvements of vitreo-retinal surgical techniques proliferative vitreoretinopathy (PVR) remains a major challenge. Surgical therapy alone may not be sufficient in complicated cases of PVR. A combination of standard techniques such as pars plana vitrectomy with a vitreous substitute and a simultaneous adjuvant pharmacological treatment for the suppression of undesired proliferation of retinal cells and retinal scarring may be a promising therapeutic approach. However, due to the narrow therapeutic range and the short biological half-life of most anti-proliferative or anti-inflammatory drugs in the vitreous cavity, intravitreal slow-release systems for extended drug delivery are desirable. Vitrectomy for PVR normally requires a vitreous substitute. Consequently, a vitreous substitute that could also serve as a slow-release system for anti-proliferative or anti-inflammatory drugs would provide several advantages. This review gives an overview of recent developments of slow-release systems that may also be suitable as vitreous substitutes. Even standard internal tamponades such as silicone oils or gases may serve as extended drug-release systems under certain conditions. In the mean time polymerised hydrogels have been developed, which apart from providing an adequate tamponade effect, may facilitate an extended intravitreal release of various anti-proliferative and anti-inflammatory drugs for several weeks.

Purpose: To evaluate the clinical safety of a taurine containing irrigation solution (AcriProTect) before its routine application in pars plana vitrectomy (PPV)., Methods: Twenty-five patients who underwent PPV were included in this prospective interventional clinical study. Standard irrigation solution containing the addendum 3 mmol/L taurine was used during PPV. Postoperative follow-up visits included a standard eye examination, corneal thickness measurements, endothelial cell counts, determination of the foveal thickness by optical coherence tomography (OCT), and an electrophysiologic examination. For statistical analysis Wilcoxon test was used., Results: Significant improvement of visual acuity (VA) was observed at the 3- and 6-month controls (P = 0.024; P = 0.002 for 3 and 6 months, respectively). Endothelial cell counts and corneal thickness at 3 and 6 months were not significantly different from preoperative values (P = 0.204; P = 0.126 for endothelial cell count and P = 0.475; P = 0.095 for corneal thickness at 3 and 6 months, respectively). Both scotopic and photopic Ganzfeld electroretinography and electro-oculography did not show significant changes during the follow-up. No increase in complication rate was detected., Conclusions: The investigation demonstrates a good biocompatibility of taurine-containing irrigation solution developed for vitrectomy in humans concomitant with habitually observed good functional outcome.