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Purpose: In October 2023, other cases with early silicone oil opacification within hours after intraocular implantation in the absence of emulsification occurred. While multiple, small series of this phenomenon are now documented during the last decade, the cause was never unmasked. In this study, we analyzed explanted patient samples, unused samples of the affected, and a control batch of the same silicone oil., Methods: The oils were examined on their optical and viscosimetric properties, interfacial tension and for presence of particles. Contamination was investigated using Inductively Coupled Plasma - Mass Spectrometry, thermogravimetric analyses, and Raman-spectroscopy. Cytotoxicity examination in ARPE-19 cells was performed. The oil's effect on pH-changes of aqueous solutions and the oil's defoaming ability were analyzed., Results: The affected batch passed all regulatory limits. However, the affected batch showed an elevated turbidity already before implantation. 3000-fold magnification revealed dispersed particles only in the affected batch. Contamination analyses revealed the absence of other elements indicating a silicon-containing contamination. The affected batch showed no in-vitro cytotoxicity but altered viscosimetric properties and a lower pH of the hydrophilic phase after inducing emulsification. Both batches did not show relevant defoaming properties., Conclusion: The results obtained combined with information from suppliers and the manufacturer suggest an elevated level of silica particles as the cause of the opacification. Based on these results, the manufacturer and suppliers of the latest affected batch adjusted cut-off values for turbidity measurements and introduced turbidity measurements of the raw material prior to distillation. Other manufacturers should follow these preventive measures.

Purpose: Exploratory analysis associated with the prospective, multicenter, randomized PRIVENT trial. To characterize the associations between laser flare photometry and anatomical and epidemiological features of rhegmatogenous retinal detachment (RRD)., Methods: The authors measured laser flare values of all 3,048 prescreened patients excluding those with comorbidities. A mixed regression analysis evaluated the strength of the influencing factors like age, sex, lens status, and presence and extent of RRD on laser flare., Results: Rhegmatogenous retinal detachment was more frequent in men (65.8%) than in women (34.2%, P < 0.001) and in right (52%) than in left eyes (48%, P = 0.045). Phakic RRD affected less quadrants and was less likely to be associated with macula-off status than pseudophakic RRD (48.4% vs. 58.0% macula off, 23% vs. 31% ≥3 quadrants, P < 0.001). Laser flare of affected eyes was significantly higher compared with fellow eyes (12.6 ± 15.2 vs. 8.3 ± 7.4 pc/ms, P < 0.001). The factors age, sex, lens status, presence of RRD, and the number of quadrants affected were independent influencing factors on laser flare. R 2 was 0.145 for phakic and 0.094 for pseudophakic eyes., Conclusion: The results indicate that there may be more factors affecting laser flare than previously assumed. This might limit flare as predictive value for PVR and retinal redetachment.

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.

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.

Purpose: To evaluate the biocompatibility of the three currently most commonly used triamcinolone acetonide (TA) preparations on retinal cells., Methods: Preservative containing KL (Kenalog-40; Bristol-Myers Squibb, Princeton, NJ), compounded preservative-free triamcinolone acetonide (PFTA; compounded from Volon A; Dermapharm, Vienna, Austria), and preservative-free triamcinolone acetonide injectable suspension (TRIESENCE; Alcon, Inc, Fort Worth, TX) (0.01-1 mg/mL) were either added directly on top or separated by a Boyden chamber filter or by a layer of vitreous to confluent cell cultures of retinal pigment epithelial cells (ARPE19) or retinal ganglion cells (RGC5). The distribution pattern of the TA crystals was assessed microscopically. Cell viability was assessed using MTT-ELISA and Live/Dead-Assay., Results: Sedimentation of triamcinolone acetonide injectable suspension, KL, or PFTA caused a pronounced decrease in cell viability. Cytotoxicity was most pronounced when triamcinolone acetonide injectable suspension and PFTA were used. Without direct sedimentation of TA crystals on top of the cells, none of the three formulations were cytotoxic. Triamcinolone acetonide injectable suspension showed the largest and most dense TA crystal aggregates on top of the cells., Conclusion: Retinal cytotoxicity of TA seems only to occur when there is intimate contact of TA crystals with the cellular membrane. Cytotoxicity depends on the number and size of TA crystal aggregates-with larger conglomerates being more harmful. Of the TA formulations tested, triamcinolone acetonide injectable suspension had the strongest tendency to form large TA crystal conglomerates and to gravitate downward.

Background: Indocyanine green-assisted internal limiting membrane (ILM) peeling was suspected to disrupt the innermost layer of the neural retina. We examined whether surgically excised specimens contain remnants of neuronal tissue., Methods: Ten patients with macular hole underwent pars plana vitrectomy and indocyanine green-assisted ILM peeling. A total of 0.1 mL of a 0.5% indocyanine green solution was applied for 15 seconds. The ILM specimens were prepared for immunohistochemistry, using a polyclonal antibody against protein gene product 9.5. Protein gene product 9.5 is a pan-neuronal marker labeling human neuronal cells. Appropriate controls to show selectivity of the antibody were performed on neuronal tissue of donor eyes. One ILM was prepared for electron microscopy., Results: A selective expression of protein gene product 9.5 was found in neuronal fibers of the retina and optic nerve of donor eyes. Only 1 of the 10 surgical ILM specimens showed a minimal focal positivity for protein gene product 9.5. No neuronal tissue was detected on the ILM by electron microscopy., Conclusion: Focal expression of protein gene product 9.5 in only 1 of 10 surgical ILM specimens argues against a general indocyanine green-related disruption of the innermost retinal layers. However, higher concentrations of the dye, longer incubation times or different solvents than used in this study may lead to different results.

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.

Purpose: To evaluate the long-term outcome of pars plana vitrectomy and primary silicone oil tamponade in patients with severe intraocular foreign body (IOFB) injuries and high risk of proliferative vitreoretinopathy (PVR)., Methods: This retrospective consecutive study included 23 patients with severe IOFB injuries who had extensive lacerations including sclera, choroid, and retina, and were complicated by predictive factors for elevated proliferative activity and an unfavorable outcome. All patients underwent pars plana vitrectomy, removal of the IOFB, and primary silicone oil tamponade and were followed up for a mean 8.9 years. Main functional outcome was assessed as final best-corrected visual acuity. Anatomic success was defined as permanent retinal attachment., Results: PVR occurred in 70% of all eyes and required 16 revisions. Silicone oil was removed in 78% of the eyes after a mean tamponade duration of 9.1 months. Complete retinal attachment was achieved in 83% of the eyes. Three eyes developed a persisting hypotony that was stabilized under permanent silicone oil. Functional stabilization was observed in the third year resulting in a final visual acuity of 20/630. Useful vision of better than 20/400 could be preserved in 55% of the patients. Only one eye underwent a late enucleation after 6.8 years., Conclusions: Primary silicone oil stabilizes the retina during the critical period of active PVR and may limit the visual loss in selected high-risk eyes in the long term.