Journal articles: 'C3F8 gas'

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Wu, Yuewei, Jian Wu, Xiaolong Wei, et al. "Theoretical Investigation of C4F7N–CO2 Mixture Decomposition Characteristics Under Extreme Conditions." Energies 18, no. 3 (2025): 591. https://doi.org/10.3390/en18030591.

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Due to their low greenhouse effect and exceptional insulating properties, C4F7N-CO2 gas mixtures have garnered significant attention. In particular, understanding the decomposition characteristics of C4F7N-CO2 is crucial for their practical use as an eco-friendly dielectric medium. At elevated temperatures, the pyrolysis of C4F7N produces high concentrations of CFN, CF3, and C2F2, along with lower levels of C3F5, C4F6N, C2F, and CN. A further increase in temperature may lead to the decomposition of CO2 into CO and additional components such as C2, C2F3, C3F4, C4F7 and C3F6, CF, CO, C3F7, C3F2, C3F, C3F3, C3F3N, C3, CF2, and CF2N. Under electrical discharge conditions, the decomposition of CO2 becomes more pronounced, forming products like CO, C2O, O2, C2O2, and C2O4, with up to 25 decomposition components observed. These include products originated from both C4F7N and CO2 and their combinations. In ultra-high electric field intensities, only small molecules such as O2, C2, C3, and N2 are detected among the decomposition products. This study aims to provide theoretical insights and valuable data to advance research into the decomposition behavior and practical engineering applications of C4F7N-CO2 gas mixtures under extreme conditions.

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Yozgat, Zübeyir. "Outcomes of 25-gauge pars plana vitrectomy using silicone oil versus C3F8 gas tamponades in rhegmatogenous retinal detachment." Kastamonu Medical Journal 5, no. 1 (2025): 70–75. https://doi.org/10.51271/kmj-0187.

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Aims: To compare the visual and anatomical outcomes, intraocular pressure (IOP) changes, and complications of 25-gauge pars plana vitrectomy (PPV) using silicone oil (SO) versus perfluoropropane (C3F8) gas tamponade in the management of rhegmatogenous retinal detachment (RRD). Methods: This retrospective study analyzed 43 eyes of 43 patients treated with 25-gauge PPV for RRD. Patients were divided into two groups: Group 1 (SO, n=25) and Group 2 (C3F8 gas, n=18). Visual acuity, IOP, and postoperative complications were evaluated over a 52-week follow-up period. Statistical comparisons were conducted using the SPSS software, and a significance level of p<0.05. Results: Both groups demonstrated significant improvements in best-corrected visual acuity (BCVA) at the 52nd week. Mean BCVA improved from 2.23 ± 0.89 logMAR to 0.30 ± 0.21 logMAR in the SO group and from 2.07 ± 0.87 logMAR to 0.19 ± 0.05 logMAR in the C3F8 group. Recurrent retinal detachment was observed in 8% of SO cases and 16.7% of C3F8 cases, with successful reattachment achieved in all reoperations. IOP increased mildly in the SO group but decreased significantly in the C3F8 group. Anti-glaucomatous therapy was initiated in 16% of patients in the SO group and 16.7% in the C3F8 group. Conclusion: Both SO and C3F8 gas tamponades are effective in achieving visual and anatomical success following 25-gauge PPV for RRD. C3F8 gas demonstrated better IOP stabilization, whereas SO was effective for more complex cases. These findings support the tailored use of tamponades based on individual patient and disease characteristics.

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Tian, Shuangshuang, Xiaoping Jin, Xiaoxing Zhang, Xiaohan Li, Zian Yuan, and Li Chen. "Study on thermal decomposition characteristics of C₆F₁₂O/O₂/CO₂ gas mixtures." AIP Advances 12, no. 11 (2022): 115003. http://dx.doi.org/10.1063/5.0123968.

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Due to its excellent insulation properties and environmental characteristics, C6F12O gas mixture shows a wide range of applications prospects in low and medium voltage gas insulated equipment. The thermal decomposition characteristics of gas insulating medium are of great importance for the industrial application of gases and the operation and maintenance of equipment. In this paper, the type and concentration of the main products of the thermal decomposition of C6F12O/O2/CO2 gas mixture are researched experimentally with different O2 mixing ratios, and the effective gas production rate is analyzed. The mechanism of thermal decomposition of C6F12O/O2/CO2 gas mixture is studied based on ReaxFF molecular dynamics. The experimental results show that the main thermal decomposition products are CF4, C2F6, C3F6, C3F8, C4F10, C5F12, and C6F14. The addition of O2 promotes the thermal decomposition of the C6F12O/O2/CO2 gas mixture. Theoretical studies show that the C6F12O in the mixture undergoes the multistage decomposition reaction. The main particles of all levels of decomposition are C3F7COCF2, CF3, CF3CFC(O) (CF2), CF2CO, C3F7, C3F7C(O) (CF2), CFC(O) (CF2), FCCO, F, CF3CFCF2, CO, and CF2. The results of the research can provide some reference for the engineering application and maintenance of C6F12O gas mixture insulated equipment.

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Hallewell, Gregory, John Dingley, Martin Doubek, et al. "Applications and Perspectives of Ultrasonic Multi-Gas Analysis with Simultaneous Flowmetry." Instruments 5, no. 1 (2021): 6. http://dx.doi.org/10.3390/instruments5010006.

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We have developed ultrasonic instrumentation for simultaneous flow and composition measurement in a variety of gas mixtures. Flow and composition are respectively derived from measurements of the difference and average of sound transit times in opposite directions in a flowing process gas. We have developed a sound velocity-based algorithm to compensate for the effects of additional gases, allowing the concentrations of a pair of gases of primary interest to be acoustically measured on top of a varying baseline from ‘third party’ gases whose concentrations in the multi-gas mixture are measured by other means. Several instruments are used in the CERN ATLAS experiment. Three monitor C3F8, (R218), and CO2 coolant leaks into N2-purged environmental envelopes. Precision in molar concentration of better than 2 × 10−5 is routinely seen in mixtures of C3F8 in N2 in the presence of varying known concentrations of CO2. Further instruments monitor air ingress and C3F8 vapor flow (at high mass flows around 1.1 kg s−1) in the 60 kW thermosiphon C3F8 evaporative cooling recirculator. This instrumentation and analysis technique, targeting binary pairs of gases of interest in multi-gas mixtures, is promising for mixtures of anesthetic gases, particularly in the developing area of xenon anesthesia.

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Zhang, Yanyan, Yan Gong, and Quanyong Yi. "Beaded Bubbles in the Eye After Vitrectomy and Gas Fill." JAMA Ophthalmology 143, no. 2 (2025): e245707. https://doi.org/10.1001/jamaophthalmol.2024.5707.

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Bor’i, Ashraf, Mahmoud A. Al-Aswad, Ahmed Abdelwahab Saad, Dina Hamada, and Ashraf Mahrous. "Pars Plana Vitrectomy with Internal Limiting Membrane Peeling in Traumatic Macular Hole: 14% Perfluoropropane (C3F8) versus Silicone Oil Tamponade." Journal of Ophthalmology 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/3917696.

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Purpose. To evaluate the outcome of 23 G PPV and ILM peeling with 14% C3F8 compared with silicone oil tamponade in cases of TMHs without spontaneous closure. Methods. A retrospective comparative study included 33 eyes with TMHs; 7 eyes healed spontaneously, and the remaining 26 eyes have been treated with PPV and ILM peeling. Silicone oil was used as a tamponade for children or adults who refused to adopt face-down position (10 cases). In all other cases (16 cases), 14% C3F8 was used. These cases were followed up for 6 months postoperatively. Results. 26 cases (22 males and 4 females) were reviewed, including 10 cases treated with silicone oil and 16 cases treated with 14% C3F8. Patients’ age ranged from 9 to 54 years. The success rate was 90% in the silicone-filled (9/10) and 94% in the gas-filled (15/16) eyes. At 6 months, the mean BCVA was 0.3 ± 0.25 in the silicone group and 0.2 ± 0.13 in the gas group (p<0.05). Conclusions. Cases of TMHs should be observed for spontaneous closure. PPV with ILM peeling should be conducted for nonclosing cases. Gas and silicone oil tamponades are equally successful in anatomical and visual outcomes. This trial is registered with CTRI/2017/06/008765.

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Bezzubov, V., S. Denisov, S. Erin, et al. "A gas ionization electromagnetic calorimeter filled with C3F8." Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 494, no. 1-3 (2002): 369–72. http://dx.doi.org/10.1016/s0168-9002(02)01494-8.

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Kapur, Neha, Charul Jain, Umang Mathur, and Virender Singh Sangwan. "Relaxing descemetotomy with compression sutures for management of acute hydrops in post-LASIK ectasia." BMJ Case Reports 18, no. 6 (2025): e263473. https://doi.org/10.1136/bcr-2024-263473.

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A woman in her 40s having post-laser-assisted in situ keratomileusis (LASIK) ectasia in both eyes developed acute hydrops in her right eye 19 years after LASIK. Anterior segment optical coherence tomography (ASOCT) did not reveal any Descemet’s membrane break, which is usually present in acute hydrops. Corneal oedema was not resolved with conservative management, so descemetopexy with perfluoropropane (C3F8) gas was performed. Despite the descemetopexy with C3F8 gas, worsening of the corneal oedema was noted. In view of the non-resolving acute hydrops even after conventional treatment, a relaxing descemetotomy and full-thickness venting incision with descemetopexy and compression sutures were planned. The complete resolution of corneal oedema with a good visual outcome was achieved using this novel technique.

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Panessa-Warren, Barbara J., James Maisel, and John B. Warren. "Alteration in vitreal structure following C3F8 injection." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 856–57. http://dx.doi.org/10.1017/s0424820100156262.

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Although the use of intraocular perfluorocarbon gases has been demonstrated to be a clinically useful procedure for retinal compression and diagnostic procedures, the effect of the gas expansion to 90% ocular volume causes the displacement of the vitreous. This investigation examines the morphological changes in the vitreous of 36 rabbit eyes following C3F8 intravitreal gas injection, by light (LM), transmission (TEM) and scanning (SEM) electron microscopy. Lincoff et al have demonstrated that C3F8gas exhibits a fourfold expansion of its volume at 3-4 days after injection into the vitreous. Following expansion the gases disappear logarithmically with the volume of the bubble following first order decay kinetics. For the rabbit, the C3F8 half-life is six days, with the total reabsorption of the gas in 40 days. To determine whether initial structural changes following gas injection eventually resolved, eyes were studied at 3, 6, 8, 16, 41 and 64 days post injection.Four pigmented and 14 albino mature (3-4 Kg) rabbits were anesthetized and given topical proparacaine anesthetic prior to injection into the inferior vitreous cavity with 0.1, 0.3 or 0.4 cc filtered C3F8. An indirect ophthalmoscope was used to direct the 30 gauge needle to a position 2-3 mm posterior to the limbus. In each case, the contralateral eye was used as the normal control. Animals were euthanized with intravenous T61 solution and the eyes immediately enucleated and frozen in liquid nitrogen. While still submerged in liquid nitrogen the tissue was placed in a deep freeze and allowed to equilibrate to −80°C for 24 hrs. Eyes were cryosectioned at −20°C and the sections placed on prechilled glass slides, cover slips, sapphire wafers or pyrolytic graphite planchets. For LM histochemistry, the frozen sections were placed in 95% ethanol 10 min and stained using a Papanicolaou method. To identify collagen, Van Gieson's picric acid fuchsin and 2.5% aniline blue were used. Proteoglycans were stained with pH 1 or pH 1.5 alcian blue or 0.5% ruthenium red. Some cryosections were freeze dried or fixed in 3% glutaraldehyde, dehydrated and dried by the critical point method (CO2) for SEM examination of an AMRay 1000A equipped with a lanthanum hexaboride gun at Brookhaven National Laboratory, Upton, NY. Tissue for routine TEM was fixed immediately following enucleation in 3% glutaraldehyde in 0.1 M cacodylate buffer (pH 7.4), post fixed in 1% aqueous OsO4, dehydrated in acetone and embedded in Epon 812. To identify and retain proteoglycans, some eyes were fixed in 2% glutaraldehyde in 0.1 M cacodylate containing 0.01% ruthenium red. Both unstained and stained (Ur-acetate and Pb-citrate) plastic thin sections were examined at 80 kV on a Philips 300.

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Elwehidy, Ahmed S., Hossam Youssef Abouelkheir, Waleed Abou Samra, Faried M. Wagdy, and Amr Mohammed Elsayed Abdelkader. "Trabeculectomy with Ologen implant versus perfluoropropane gas bubble for open angle glaucoma in pseudophakic eyes." International Journal of Ophthalmology 14, no. 4 (2021): 510–16. http://dx.doi.org/10.18240/ijo.2021.04.05.

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AIM: To evaluate the safety and efficacy of augmented trabeculotomy with Ologen versus perfluoropropane in management of pseudophakic glaucoma. METHODS: This is a comparative randomized study included 57 pseudophakic eyes of 57 patients with medically uncontrolled open angle glaucoma (OAG). Twenty-nine patients were allocated in group I (trabeculectomy with Ologen; trab-ologen group), while 28 patients were assigned in group II (trabeculectomy with perfluoropropane gas bubble; trab-C3F8 gas bubble group). RESULTS: The intraocular pressure (IOP) was significantly reduced in both study groups at all postoperative follow up intervals (1wk, 3, 6, 12, 18, 24, 30 and 36mo, P&#x0026;#x003C;0.001). The differences between the mean IOP values of both groups remained statistically insignificance during the early 12 months of follow up. However, the trab-ologen group achieved a statistically significant reduction over the trab-C3F8 gas bubble group during the last 24 months of follow up. CONCLUSION: Augmentation of trabeculectomy with either Ologen implant or perfluoropropane gas bubble are associated with strict long term IOP control and evident safety in medically-uncontrolled pseudophakic eyes with OAG.

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Kulikov, A. N., E. N. Nikolaenko, V. V. Volkov, and V. F. Danilichev. "Electrogenesis of Retina and Optic Nerve after Vitrectomy for the Primary Full-Thickness Macular Hole." Ophthalmology in Russia 16, no. 1 (2019): 46–55. http://dx.doi.org/10.18008/1816-5095-2019-1-46-55.

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Purpose. To study the dynamics of electrophysiological parameters of the retina and optic nerve after vitrectomy for a primary fullthickness macular hole.Patients and Methods. Electrophysiological examination was performed in 40 patients (40 eyes) before vitrectomy, on the 1st, 3rd, 7th, 14th, 30th, 60th, 180th day after the operation. Three groups of patients were formed depending on the intraocular tamponade: the first group — air tamponade, the second group — gas (C3F8) tamponade, the third group — silicone oil tamponade.Results. In the first, second and third groups significant decrease in the retinal and optic nerve electrogenesis was revealed on the 1st day (p < 0.001) after vitrectomy. By the end of observation period all electrophysiological indices in the first, second and third groups recover to normal levels, excluding the retinal cone system and optic nerve parameters in the third group. Electrophysiological indices recovered twice as slow in the second group, compared to the first group, due to C3F8 gas tamponade inhibitory effect. In the first and second groups the photoreceptors recovered twice as fast as bipolar cells.Conclusions. Vitrectomy causes significant inhibition of photoreceptors, bipolar and ganglion cells electrogenesis. The duration of vitrectomy is a significant negative factor determining retinal and optic nerve electrogenesis inhibition in the postop. Intraocular C3F8 gas, silicon oil tamponade (compared to air tamponade) is a significant adverse factor affecting retinal and optic nerve electrogenesis inhibition in the postop. The primary full-thickness macular hole diameter is a significant factor in inhibiting electrogenesis of the retinal cone system. Photoreceptors have a greater rehabilitation ability than bipolar cells.

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Lee, Bong Jae, Yujin Hwang, Dong Ki Jo, and Jongmoon Jeong. "A Study on Greenhouse Gas (PFCs) Reduction in Plasma Scrubbers to Realize Carbon Neutrality of Semiconductors and Displays." Atmosphere 14, no. 8 (2023): 1220. http://dx.doi.org/10.3390/atmos14081220.

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Perfluorinated compounds (PFCs) are used for manufacturing purposes in the semiconductor and display industries, resulting in an increased need for emission reduction due to the significant global warming potential of the associated greenhouse gases. The decomposition characteristics of etch-type and water film (WF)-type plasma-wet scrubbers were investigated. The PFCs used in the study were CF4, SF6, NF3, CHF3, C2F6, C3F8, and C4F8, and the destruction removal efficiency (DRE) and by-product gas generation rate were confirmed based on the changes in the parameters (total flow rate and power) of the plasma-wet scrubber. When the total flow rate reached 100 L/min and the measured maximum power (11 kW), the reduction efficiency of CF4 in the etch type was 95.60% and the DRE of other PFCs was 99.99%. Moreover, for the WF type, the DRE of CF4 was 90.06%, that of SF6 was 96.44%, and that of other PFCs was 99.99%. When the total flow rate reached 300 L/min and 11 kW, the DRE of SF6 in the etch type was 99%, and the DRE of NF3, CHF3, C2F6, C3F8, and C4F8 was 95.57%, 87.06%, 70.74%, 81.45%, and 95.59%, respectively. In addition, in the WF type, the DRE of SF6 was 94.39%, and the DRE of NF3, CHF3, C2F6, C3F8, and C4F8 was 99.80%, 95.34%, 85.38%, 88.49%, and 98.22%, respectively. The decomposition efficiency was high for the etch type for gases with small flow rates or no by-product gas generation. The by-product gas generation rate was significantly lower for the WF type.

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Veith, Miroslav. "Treatment of Vitreomacular Traction with Intravitreal Injection of Perfluoropropane." Czech and Slovak Ophthalmology 75, no. 4 (2020): 182–87. http://dx.doi.org/10.31348/2019/4/2.

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Purpose: To evaluate the effect of one intravitreal injection of expansile gas in the treatment of vitreomacular traction (VMT). Methods: A retrospective review of eyes with VMT treated with singl injection of 0,3 ml of 100% C3F8 gas was performed. The procedure was performed on an outpatient basis under topical anesthesia. Results: Twelve consecutive patient (14 eyes) with symptomatic VMT underwent pneumatic vitreolysis. Mean extend of vitreomacular adhesion was 490,5 µm (408-751). A posterior vitreous detachment developed in 13 eyes (92,9 %) after a single gas injection, in 11 eyes (84,6 %) during the first month of follow-up, in 2 eyes within two month of injection. Mean baseline and last BCVA were 0,5 (0,16-0,18) and 0,67 (0,2-1,0) respectively (p < 0,001). Mean folow-up time was 5,8 (1-16) months. The procedure was also successful in two eyes, which where previously unsuccessfuly treated with ocriplasmin. One eye formed a macular hole. There were no other complication. Conclucion: Intravitreal injection of C3F8 is an effective, safe and inexpensive therapy of vitreomacular traction.

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Petrou, Petros, Despoina-Georgia Kokosiouli, Trushar Patel, et al. "Trapped Pre-Macular Bubble of Octafluoropropane Gas Masquerading as Retained Submacular Perfluorocarbon Liquid." Case Reports in Ophthalmology 10, no. 2 (2019): 200–204. http://dx.doi.org/10.1159/000499855.

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Introduction: To demonstrate, with the aid of retinal imaging, an abnormal post-operative macular appearance caused by the presence of a “fragmented” pre-retinal bubble of octafluoropropane (C3F8) masquerading as retained subretinal perfluorocarbon liquid (PFCL). Methods: This is an interventional case presentation. Results: Colour fundus photography high-resolution spectral domain-optical coherence tomography (SD-OCT) and clinical progress demonstrate that the abnormal reflex was caused by the presence of a small fragment of C3F8 becoming lodged at the pre-foveal area. Conclusion: Submacular entrapment of various substances used during vitrectomy has been described in a number of case reports and case series. To our knowledge, this is the first described case of a retained fragment of fluorocarbon gas trapped at the macula following successful retinal detachment repair and highlights a previously unreported cause of an abnormal foveal appearance. However, clinical examination together with the use of SD-OCT is helpful in differentiating the appearance from that seen in other retained vitrectomy adjuncts.

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Brilliyanto, Frisma Sagara, and Wimbo Sasono. "CASE REPORT Management Cataract Complication and Malignant Glaucoma After Viterectomy Surgery and C3F8 Gas Tamponnade." Jurnal SainHealth 4, no. 1 (2020): 11. http://dx.doi.org/10.51804/jsh.v4i1.704.11-15.

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Report a clinical presentation of patient with rhematogenous retinal detachment by viterectomy and high myopia with C3F8 gas tamponade. A 20-year-old female came into the outpatient clinic with blurry vision on the right eye as her chief complaint. It had been happening since 1 month ago. In examination, we found result of visual acuity RE 1/300 and LE 1/60 correction Sferis-16.00 5/7.5, anterior segment in a normal range. In posterior segment evaluation, there were RE detachment on 3-11 o’clock position and hole on 6 and 8 o’clock position. Then we performed vitrectomy and C3F8 gas tamponade. The first day after surgery, we found IOP 19,6 mmHg and Von Herrick III. Then after the second day, we found a pain on the right eye, TIO 47.3 mmHg, Von Herrick 0 and opaque lens. Then we performed iridectomy and intravitreal gas aspiration. After it were done, we found IOP 17.3 mmHg and Von Herrick 0. In anterior segment OCT evaluation, we found a narrow angle anterior segment. Then we planned to do a cataract extraction with using viscoelastic to perform the anterior chamber.Malignant glaucoma can occur in cases after vitrectomy action due to aqueous misdirection and emphasis on gas expansion on tamponade. Cataract extraction and gas aspiration can help open the anterior chamber and the intraocular pressure returns to normal

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Kimura, S. "P-890 Thoracic cavity management with C3F8 gas after pneumonectomy." Lung Cancer 49 (July 2005): S353—S354. http://dx.doi.org/10.1016/s0169-5002(05)81383-2.

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Haas, Anna-Maria, Christoph Mayer, Anton Haas, and Werner Wackernagel. "Effect of intravitreal C3F8 gas in patients with vitreomacular traction." Spektrum der Augenheilkunde 32, no. 6 (2017): 228–38. http://dx.doi.org/10.1007/s00717-017-0382-5.

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Nadig, Ramya R., B. Deepak, Vidya Neelamegam, George Moussa, and Rajiv Raman. "Global warming impact of fluorinated gases in ophthalmic surgeries at a tertiary eye center in India." Indian Journal of Ophthalmology 72, no. 5 (2023): 692–96. http://dx.doi.org/10.4103/ijo.ijo_1775_23.

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Purpose: Global warming is one of the greatest health threats of the 21st century. The ophthalmic sector contributes to the emission of greenhouse gases, thus altering the natural environment. There is currently no data on global emissions of fluorinated gases in ophthalmic surgery. This retrospective study from 2017 to 2021 aims to report the carbon dioxide (CO2) equivalence of sulfur hexafluoride (SF6), hexafluoroethane (C2F6), and octafluoropropane (C3F8) at a tertiary eye center. Methods: Data collected from 1842 surgical procedures that used injections of fluorinated gases were analyzed. Environmental impact (global warming potential over 100 years) was calculated by converting milliliters to grams by using modified ideal gas law at standard temperature and pressure for the canisters and then to their CO2 equivalence. Results: Though 70% of surgeries used C3F8, the least greenhouse effect causing fluorinated gas, the total carbon emission was 1.4 metric tons. The most common indication was macular hole surgery (36.86%). Conclusion: This study paves a step toward analyzing the problem statement, thus awakening us to contemplate options to make ophthalmic surgeries greener.

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Shetty, Prerana A., Sushank A. Bhalerao, Sowjanya Vuyyuru, Uma Y. Thigale, and Rajavardhan Mallipudi. "Endoilluminator-assisted management of acute hydrops in pellucid marginal corneal degeneration (PMCD) with compression sutures and intracameral perfluropropane (C3F8)." Indian Journal of Ophthalmology - Case Reports 3, no. 4 (2023): 1177–79. http://dx.doi.org/10.4103/ijo.ijo_735_23.

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In this case, a male in his 30s presented to the clinic with blurring of vision, sudden whiteness, and pain in the left eye for 10 days. All preliminary examinations were recorded. He was a known case of Pellucid marginal corneal degeneration (PMCD). Clinical examination revealed corneal edema due to acute hydrops. Anterior segment optical coherence tomography (OCT) showed increased corneal thickness and a large descemets detachment. Endoilluminator-assisted compression sutures were placed along with intracameral C3F8 gas. As the tear was large, a 10-0 prolene suture was used instead of the conventional 10-0 nylon. This is the first case in literature in which acute hydrops in PMCD was managed with compression sutures (10-0 prolene) along with the injection of intracameral perfluropropane (C3F8) with the help of intraoperative use of endoilluminator.

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Kodavoor, Shreesha Kumar, Komal Bhimrao Patekar, and Ramamurthy Dandapani. "An unusual case of late spontaneous reattachment of Descemet membrane detachment after deep anterior lamellar keratoplasty: A case report." Indian Journal of Ophthalmology - Case Reports 3, no. 4 (2023): 985–88. http://dx.doi.org/10.4103/ijo.ijo_4_23.

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Deep anterior lamellar keratoplasty (DALK) is a feasible option in children with advanced keratoconus with or without stromal scarring. Descemet membrane detachment (DMD) and formation of double anterior chamber is one of the rare but serious complication of DALK surgery. Various treatment methods like descemetopexy with air, perfluoropropane gas (C3F8), and SF6 (sulfur hexafluoride gas) can be tried. We report a case of spontaneous reattachment of DMD in a pediatric male patient with Descemet membrane microperforation during DALK.

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Liu, Wei, Xinjie Qiu, Xiaoxing Zhang, Shuangshuang Tian, Zian Yuan, and Weihao Liu. "Adsorption Properties of ZSM-5 Molecular Sieve for Perfluoroisobutyronitrile Mixtures and Its Fluorocarbon Decomposition Products." Chemosensors 10, no. 4 (2022): 121. http://dx.doi.org/10.3390/chemosensors10040121.

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Perfluoroisobutyronitrile (C4F7N), an environment-friendly insulating gas, has excellent insulating properties and has the potential to be used in gas-insulated equipment when mixed with CO2. Selecting suitable adsorption materials to adsorb the decomposition products of the C4F7N mixture can ensure the safe and stable operation of the gas-insulated equipment and the personal safety of the operators in the electric power industry. The adsorption characteristics of the ZSM-5 molecular sieve on C4F7N and its five fluorocarbon decomposition products were investigated by adsorption experiments. The results show that the ZSM-5 molecular sieve has a certain adsorption effect on six fluorocarbon gases; the adsorption performance of C3F6 and C3F8 are the best, with an adsorption efficiency over 85%, while the concentration of CO2 and C4F7N is affected by the ZSM-5 molecular sieve. At the same time, the paper based on the Metropolis Monte Carlo simulation of Materials Studio software found that the ZSM-5 molecular sieve has the strongest adsorption effect on C4F7N molecules and the weakest adsorption effect on CO2 molecules. The stronger the polarity of the gas molecule, the more obvious the adsorption effect of molecular sieve structure on it. As a result, the ZSM-5 molecular sieve could be used in tail gas purification of insulated equipment, as well as to provide solutions for the development and production of protective equipment.

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Tang, Nian, Jia Nie, Jie Liu, et al. "Study on the decomposition mechanism and insulation stability of HFO-1336mzz(E)/air mixtures as a new environment-friendly insulation medium under AC voltage." AIP Advances 13, no. 4 (2023): 045007. http://dx.doi.org/10.1063/5.0134818.

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As one of hydrofluoroolefins (HFOs), HFO-1336mzz(E) is regarded as a promising eco-friendly alternative insulation medium to Sulfur Hexafluoride (SF6) owing to its excellent environmental effect and insulation property. To study the decomposition mechanism and insulation stability, the decomposition experiment of a 0.5 MPa mixture containing 8% HFO-1336mzz(E) and 92% air was performed under AC breakdown conditions. The results indicated that the main decomposition products were CF4, C2F6, C3F8, CF3H, CF3C=CH, CF3CH=CHF(E), CF3CHF2, CF3CH=CH2, CF2=CFH, CF2=CH2, CH≡CH, C4H2F6O, CF3O3CF3, etc. Among them, the generation of C3F8, CH≡CH, and C4H2F6O was relatively more difficult than others. Thus, these three compounds can be considered typical decomposition products. New elements, namely C, F, and N, appeared on the electrode surface after breakdowns compared to the state before breakdowns. It can be concluded that some complex chemical reactions were triggered between the electrode material and gas mixture under the action of breakdown discharge. Additionally, the breakdown voltage of the HFO-1336mzz(E)/air mixture almost remained unchanged, showing that the gas mixture still exhibited an excellent insulation stability after multiple breakdowns.

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Osusky, R., and J. Faulborn. "Gesichtsfelder nach erfolgreicher Vitrektomie und C3F8-Gas-Tamponade wegen PVR-Amotio." Spektrum der Augenheilkunde 5, no. 4 (1991): 155–57. http://dx.doi.org/10.1007/bf03163844.

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Jee, Dong Hyun, and Hyun Seung Kim. "The effect of C3F8 gas on corneal endothelial cells in rabbits." Japanese Journal of Ophthalmology 54, no. 6 (2010): 602–8. http://dx.doi.org/10.1007/s10384-010-0884-z.

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Shah, Susmita G., M. S. Sridhar, and Virender S. Sangwan. "Acute corneal hydrops treated by intracameral injection of perfluoropropane (C3F8) gas." American Journal of Ophthalmology 139, no. 2 (2005): 368–70. http://dx.doi.org/10.1016/j.ajo.2004.07.059.

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Xiao, Song, Shuangshuang Tian, Xiaoxing Zhang, et al. "The Influence of O2 on Decomposition Characteristics of c-C4F8/N2 Environmental Friendly Insulating Gas." Processes 6, no. 10 (2018): 174. http://dx.doi.org/10.3390/pr6100174.

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The c-C4F8 gas is considered to have great potential as a gaseous medium for gas-insulated equipment, due to its good insulation properties and its relatively low greenhouse gas potential (GWP) relative to SF6. However, the decomposition is an important indicator of its use in equipment. In this paper, the decomposition characteristics of c-C4F8 and the influence by oxygen have been explored through experiments and theoretical calculations. Firstly, the breakdown test of mixed gas was carried out and the precipitated elements of the electrodes and breakdown products of gas mixture were analyzed by X-ray photoelectron spectroscopy (XPS) and gas chromatography mass spectrometry (GC-MS). At the same time, the differences in decomposition products have also been studied when a small amount of O2 was present. The path and mechanism of c-C4F8 decomposition is then discussed, based on density functional theory (DFT). The results show that the black powdery substance descends on the electrode surface after the breakdown of the mixture of c-C4F8/N2 gas containing O2, and its main constituent elements are C, O and F. O2 can promote the decomposition of c-C4F8. The mixture with O2 produced a large number of additional toxic and corrosive COF2 in addition to generating more CF4, C2F4, C2F6, C3F6 and C3F8. The GWP values of the products are lower than SF6. Comprehensive insulation properties and decomposition characteristics, c-C4F8 should not be mixed with dry air for use, and the oxygen content should be strictly controlled in c-C4F8 mixed gas.

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Aziz, Ahmad, Sonali Nagendran, Mike Perry, and Vickie Lee. "Orbital emphysema with loss of vision following undiluted intravitrel perfluoropropane administration." Advances in Ophthalmology & Visual System 9, no. 2 (2019): 53–54. http://dx.doi.org/10.15406/aovs.2019.09.00345.

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We present a case of orbital emphysema leading to orbital compartment syndrome and permanent visual loss secondary to expansion of perfluoropropane (C3F8) gas, which was injected into the vitreous cavity as a gaseous tamponade during vitreoretinal surgery and inadvertently undiluted. Orbital emphysema leading to orbital compartment syndrome resulted in visual loss despite treatment with lateral canthotomy, cantholysis and surgical decompression. Orbital compartment syndrome is an ophthalmic emergency and should be treated immediately with lateral canthotomy and cantholysis. There is little literature on the management and outcomes of orbital compartment syndrome with expansile gases such as C3F8 which may quadruple in volume within 96 hours. Hyperbaric oxygen has been reported to be of benefit but patients may require orbital decompression for definitive treatment. Although orbital emphysema with air rarely threatens vision orbital emphysema with expansile gases can lead to orbital compartment syndrome and visual loss.

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Kimura, Suguru. "Thoracic cavity volume control in patients after pneumonectomy. Comparison of SF6 gas with C3F8 gas." Journal of the Japanese Association for Chest Surgery 16, no. 6 (2002): 733–36. http://dx.doi.org/10.2995/jacsurg.16.6_733.

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Shkvorchenko, D. O., E. S. Khrisanfova, and D. G. Uzunyan. "Surgical treatment of rhegmatogenous retinal detachment using air tamponade and C3F8 gas tamponade." Fyodorov journal of ophthalmic surgery, no. 1 (March 29, 2023): 25–30. http://dx.doi.org/10.25276/0235-4160-2023-1-25-30.

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Relevance. Retinal detachment is a serious disease, that requires immediate surgical treatment. If there is no doubt about the need for urgent surgical treatment, then the question of choosing tamponing substance after retinal immobilization remains open. Often there are no clear criteria for choosing one or another tamponing substance and this issue is determined by the preference of the surgeon. Purpose. To evaluate effectiveness and compare result of surgical treatment of rhegmatogenous retinal detachment using air and C3F8 gas tamponade. Material and methods. Surgical treatment of 43 patients diagnosed with rhegmatogenous retinal detachment was performed and the results of treatment were evaluated. All patients were divided into 2 groups. The first group included 23 patients with the best corrected visual acuity 0.01– 0.9 (±0.06). Surgical treatment of patients from this group was completed with sterile air tamponade. The second group included 20 patients with the best corrected visual acuity of 0.01–0.8 (±0.08). Surgical treatment was completed with a 2.5% C3 F 8 gas tamponade. Results. By the third month of follow-up after surgical treatment B-scan data showed no pathology in all cases of both groups. Visual acuity in group 1 was 0.55-1.0 (±0.063), in group 2 was 0.45–1.0 (±0.061). Light sensitivity in group 1 was 24.5–30.1 (±0.34) dB, in group 2 was 23.1–27.7 (±0.41) dB. Conclusion. Given the comparable clinical results, air tamponade in surgery for rhegmatogenous retinal detachment is preferable than using 2.5% C 3 F 8 gas tamponade. Key words: rhegmatogenous retinal detachment, surgical treatment, air tamponade, C3F8 gas tamponade

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Chowdhury, Tuhin, and Aditya Pradhan. "Acute Hydrops with Micro-Cornea – an Extremely Rare Condition: A Case Report." Ophthalmology @ Point of Care 1, no. 1 (2017): oapoc.0000003. http://dx.doi.org/10.5301/oapoc.0000003.

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Purpose To report the first case of a one-eyed child with micro-cornea, coloboma of iris and acute hydrops without any other disorder of the cornea or systemic disease. Methods Intracameral injection of perfluoro propane (C3F8) gas was performed under general anaesthesia. Results Resolution of the hydrops was observed at 1st week of follow-up, which was confirmed by anterior segment optical coherence tomography. Patient was subsequently lost to follow-up. Conclusions Intracameral injection of perfluoro propane gas is an effective way to quickly resolve acute hydrops. In this specific case, the patient presented with micro-cornea and no other corneal abnormalities.

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LU, DA-WEN, CHARN-JUNG CHANG, CHIAO-HSI CHIANG, and PING-I. CHOU. "Subconjunctival Retention of C3F8 Gas Increased Success Rates of Trabeculectomy in Rabbits." Journal of Ocular Pharmacology and Therapeutics 14, no. 4 (1998): 305–12. http://dx.doi.org/10.1089/jop.1998.14.305.

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Modi, Aditya, Anantharaman Giridhar, and Mahesh Gopalakrishnan. "SULFURHEXAFLUORIDE (SF6) VERSUS PERFLUOROPROPANE (C3F8) GAS AS TAMPONADE IN MACULAR HOLE SURGERY." Retina 37, no. 2 (2017): 283–90. http://dx.doi.org/10.1097/iae.0000000000001124.

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STEFANIOTOU, M. "Sulfur hexafluoride (SF6) versus perfluoropropane (C3F8) gas tamponade for macular hole surgery." Acta Ophthalmologica 87 (September 2009): 0. http://dx.doi.org/10.1111/j.1755-3768.2009.3416.x.

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Barwar, Gulshan, and Gaurav R. Ghag. "It’s a trap - Trapped bubble of octafluoropropane (C3F8) gas at the fovea." Indian Journal of Ophthalmology - Case Reports 4, no. 1 (2024): 288–89. http://dx.doi.org/10.4103/ijo.ijo_861_23.

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Marková, Kateřina, Pavel Němec, Petr Červený, et al. "Pneumatic Vitreolysis using C3F8 Gas in Treatment Naive Patients with Vitreomacular Traction." Czech and Slovak Ophthalmology 80, no. 5 (2024): 256–63. https://doi.org/10.31348/2024/34.

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Purpose: Evaluation of the effectiveness of pneumatic vitreolysis in disrupting vitreomacular traction in our own cohort of patients. Methodology: Prospective follow-up of 21 eyes of 18 patients with focal VMT (adhesion width < 1500 µm) who underwent intravitreal injection of 0.3 ml of 100% perfluoropropane between January 2015 and December 2020. The patients were observed for 90 days. Results: Release of VMT was achieved on the 28th day of observation in 15 out of 21 eyes (71.4%), and by the 90th day in 19 out of 21 eyes (90.5%). The average width of adhesion in our patients was 382 µm (±212 µm). Average best corrected visual acuity in our cohort was initially 0.77 (±0.21), after 28 days 0.74 (±0.30), and after 3 months 0.82 (±0.21). At the end of the follow-up period, we did not observe a statistically significant improvement in vision. Macular holes developed in two eyes, but spontaneously closed within 1 month of observation, and no more complications were observed in the cohort. Conclusion: Pneumatic vitreolysis by intravitreal injection of C3F8 gas is an effective and inexpensive option for the management of symptomatic vitreomacular traction. The incidence of serious adverse events in our follow-up was significantly lower than in recently published series. The method of management should be selected individually according to the parameters of adhesion, macular hole and associated ocular pathologies.

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Kaur, Jasmeet, Krishnendu Nandi, Rupak Kanti Biswas, and Sourav Sinha. "Bilateral idiopathic macular hole in a young female." BMJ Case Reports 18, no. 5 (2025): e265350. https://doi.org/10.1136/bcr-2025-265350.

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Full thickness macular hole (FTMH) is common in the adult population but rare in young individuals. FTMH in young patients are generally unilateral and often associated with trauma or high myopia. Here, we report the first documented case of bilateral idiopathic full thickness macular hole in a young female in her early 30s who underwent 25-gauge transconjunctival pars plana vitrectomy with brilliant blue-assisted internal limiting membrane peel and C3F8 gas tamponade with subsequent macular hole closure.

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Chen, Xiang, Yi Yao, Xiaolu Hao, Xiaocui Liu, and Tiecheng Liu. "A Comparative Study of Vitrectomy Combined with Internal Limiting Membrane Peeling for the Treatment of Idiopathic Macular Hole with Air or C3F8 Intraocular Tamponade." Journal of Ophthalmology 2018 (July 2, 2018): 1–6. http://dx.doi.org/10.1155/2018/1672501.

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Purpose. The treatment of idiopathic macular holes has been basically modeled, and vitreoretinal surgery is recognized as an effective treatment. However, the postoperative tamponade of gas will still make the patient uncomfortable and may have related complications. The purpose of this study is to investigate whether air as an intraocular tamponade is equivalent to gas and what advantages may exist. Methods. A retrospective study was performed in one hundred and ninety-eight patients from 2013 to 2017; 112 received gas tamponade and 86 received air tamponade. After receiving retinal surgery, the outcomes of best corrected visual acuity, intraocular pressure, slit lamp examination, fundus examination, and imaging of the macula by spectral-domain optical coherence tomography were analyzed. Results. Before operation, there was no statistically significant difference in age, sex, macular hole diameter, or visual acuity between groups. The median follow-up period for the C3F8 group was 26 months, and the median follow-up for the air group was 25 months. After the operation, the best corrected visual acuity and macular hole closure rate were not significantly different between the two groups. The face-down time after the operation, the incidence of lens opacity on the third postoperative day, the intraocular pressure on the third postoperative day, and the operation time were significantly different between the two groups. Conclusions. In idiopathic macular hole surgery, the effect of air as an intraocular tamponade material can be similar to that of C3F8 but has fewer complications. In particular, it is a better choice for patients for whom the face-down position is not suitable.

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Al Rubaie, Khalid, Juan V. Espinoza, Andres F. Lasave, Dario Savino-Zari, Fernando A. Arevalo, and J. Fernando Arevalo. "Pneumatic Displacement with Perfluoropropane Gas and Intravitreal Tissue Plasminogen Activator for Subretinal Subfoveal Hemorrhage after Focal Laser Photocoagulation in Central Serous Chorioretinopathy." Case Reports in Ophthalmological Medicine 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/592746.

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Objective. To report the visual and anatomic outcomes of pneumatic displacement with perfluoropropane (C3F8) gas and intravitreal tissue plasminogen activator (IVTPA) for subretinal subfoveal hemorrhage after focal laser photocoagulation in central serous chorioretinopathy (CSCR).Method. Interventional, retrospective case report of one eye (one patient). Outcome measures included visual acuity (VA), central macular thickness (CMT), and size of the lesion at two weeks of followup. Fluorescein angiography (FA) and optical coherent tomography (OCT) were used to measure anatomic outcomes.Results. A 35-year-old man with history of chronic CSCR received focal laser photocoagulation in the right eye two days before presentation. At initial examination, VA was 20/200 (ETDRS chart), CMT was 398 μ, and a subretinal subfoveal hemorrhage was seen. Tissue plasminogen activator (tPA) at a dose of 25 µg/0.1 mL was injected intravitreally before intravitreal C3F8 injection, and prone positioning was indicated postoperatively. At 24 hours, the hemorrhage had been displaced inferiorly and VA improved to 20/100. Two weeks later, VA improved to 20/80, CMT decreased to 225 μ, and the hemorrhage decreased without foveal involvement.Conclusions. The technique seems safe and effective in treating visually significant subretinal subfoveal hemorrhage.

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Schindler, Philipp, Luca Mautone, Eileen Bigdon, Vasyl Druchkiv, Martin Stefan Spitzer, and Christos Skevas. "Lens densitometry for assessment and prediction of cataract progression after pars plana vitrectomy with C3F8-gas for retinal detachment." PLOS ONE 16, no. 7 (2021): e0254370. http://dx.doi.org/10.1371/journal.pone.0254370.

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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.

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Sitnik, Galina V. "Corneal hydrops: diagnosis and treatment." Ophthalmology journal 13, no. 2 (2020): 31–42. http://dx.doi.org/10.17816/ov34789.

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Acute corneal hydrops is a pathological condition which clinically presents by marked corneal edema developing due to a break in Descemets membrane. Background. To analyze the results of diagnosis and treatment in patients with acute corneal hydrops. Materials and methods. 42 patients (47 eyes) suffering from acute corneal hydrops were included in the study. This condition appeared on both eyes simultaneously or sequentially in 5 patients. Mean age was 28.7 10.1 years (from 19 to 54 years), 31 men, 11 women. In case of complications or inefficacy of medical therapy surgical procedures were performed: 10% gas (C3F8, SF6) injection into the anterior chamber, amniotic membrane transplantation, partial lamellar keratoplasty, DALK, PKP. Results. Duration of corneal ectasia before acute hydrops occurrence was 12.6 4.6 years. Disease was not diagnosed before in 11.9%. Corneal thickness varied from 692 98 m in focal hydrops to 1200 220 m in total hydrops. Area of edema, height of Descemet detachment and gap between break margins were significantly above in cases of subtotal and total hydrops compared with focal and partial hydrops (2, p 0,001). Injection of 10% gas (C3F8, SF6) in the anterior chamber allowed to significantly accelerating the resolution of this condition in cases of subtotal and total hydrops. Conclusion. Analysis of this case series showed the feasibility of a differentiated approach in the treatment of acute corneal hydrops depending on its severity.

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Ünsal, Erkan, Kadir Eltutar, Belma Karini, and Osman Kızılay. "Assessment of Anterior Segment Changes in Pseudophakic Eyes, Using Ultrasonic Biomicroscopic Imaging, after Pars Plana Vitrectomy with Silicone Oil or Gas Tamponade." Journal of Ophthalmology 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8303792.

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Objective. To evaluate the morphological changes of the anterior segment using ultrasonic biomicroscopy (UBM) imaging in pseudophakic patients who underwent pars plana vitrectomy (PPV) with silicone oil or gas (C3F8) internal tamponade agent injection.Method. This prospective study included pseudophakic patients with planned PPV, divided into two groups according to internal tamponade agent: those in which silicone oil was used (n=27, Group 1) and those in which gas (C3F8) was used (n=24, Group 2). UBM measurements were performed in the supine position before and one week after surgery.Results. In patients of Group 1, postoperative trabecular meshwork-ciliary process distance (T-CPD) and iris-ciliary process distance (I-CPD), according to preoperative values, were found to be statistically significantly reduced, and postoperative mean value of scleral thickness (ST) and intraocular pressure (IOP), according to preoperative value, was found to be statistically significantly increased. In patients of Group 2, postoperative mean values of anterior chamber depth (ACD), ciliary body thickness (CBT), T-CPD, I-CPD, and IOP, according to preoperative values, were found to be statistically significantly reduced. Preoperatively, in Group 2 patients, according to Group 1 patients, TIA and IOP were found to be statistically significantly increased. Preoperative and postoperative IOP between the measured parameters with UBM showed no statistically significant correlation.Conclusions. Gases cause more morphological changes in the anterior segment structures. It is thought that complications such as increased intraocular pressure can be seen more frequently for this reason.

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KOH, H. J. "Treatment of subhyaloid haemorrhage with intravitreal tissue plasminogen activator and C3F8 gas injection." British Journal of Ophthalmology 84, no. 11 (2000): 1318l—1318. http://dx.doi.org/10.1136/bjo.84.11.1318l.

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Briggs, M., D. Wong, C. Groenewald, J. McGalliard, J. Kelly, and J. Harper. "The effect of anaesthesia on the intraocular volume of the C3F8 gas bubble." Eye 11, no. 1 (1997): 47–52. http://dx.doi.org/10.1038/eye.1997.10.

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Fang, Zhi, Hongliang Huang, Liang Sun, et al. "A low-cost and stable metal–organic framework featuring electropositive microenvironment for efficient recovery of C3F8 electronic specialty gas and record C3F8/N2 separation." Chemical Engineering Journal 516 (July 2025): 163987. https://doi.org/10.1016/j.cej.2025.163987.

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Farouk Abdelkader, Mohamed, Shaaban Abd-Elhamid Mehany Elwan, and Ahmed Shawkat Abdelhalim. "Double Retinal Tamponade for Treatment of Rhegmatogenous Retinal Detachment with Proliferative Vitreoretinopathy and Inferior Breaks." Journal of Ophthalmology 2020 (October 7, 2020): 1–6. http://dx.doi.org/10.1155/2020/6938627.

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Purpose. To evaluate the efficacy and safety of the simultaneous use of short-term perfluoro-n-octane (PFO) with perfluoropropane (C3F8) gas to achieve retinal reattachment in eyes with rhegmatogenous retinal detachment (RRD) with proliferative vitreoretinopathy (PVR) grade C and multiple retinal breaks including inferior breaks. Design. This is a prospective interventional case series study. Patients and Methods. The study was a prospective noncomparative interventional study. It included 30 eyes of 30 patients who had RRD with PVR grade C and multiple retinal breaks including inferior tears attending the vitreoretinal unit of Minia University Hospital, Egypt. The mean age was 50.2 ± 10.63 years; 18 patients were females and 12 were males. Combined phacoemulsification and 23 G pars plana vitrectomy (PPV) with double retinal tamponade by C3F8 and PFO were done, and PFO was removed in 10–14 days. The patients were followed up for one year. The primary outcome was to achieve successful retinal reattachment, and the secondary outcomes were visual improvement and occurrence of complications. Results. Successful retinal reattachment was obtained in 28 eyes out of 30 (93.3%), and 2 eyes (6.7%) had recurrent RD. Best-corrected distance visual acuity (BCDVA) in logMAR was significantly improved from baseline 1.74 ± 0.05 to 0.93 ± 0.04, 0.82 ± 0.05, 0.80 ± 0.07, and 0.73 ± 0.055 at follow-up visits 3, 6, and 9 months and one year, respectively ( P ≤ 0.001 ). There were no serious ocular complications recorded. Conclusions. The results of this study indicated that primary vitrectomy with simultaneous use of both C3F8 and short-term PFO as retinal tamponades was effective and safe in the management of complex cases of RRD with PVR grade C and inferior breaks. This trial is registered with NCT04168255.

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Ibrahim, Visa Musa. "Recognition of Protrusion Defect Fault in Gas Insulated Switchgear Base on SF6 Decomposition Product." International Journal of Advanced Research in Computer Science and Software Engineering 8, no. 1 (2018): 131. http://dx.doi.org/10.23956/ijarcsse.v8i1.545.

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A solid analytic procedure of Gas insulated switchgear condition checking is utilized in this studies as a part of exploration for the detection of sulphur hexafluoride gas (SF6) decomposition by-product because of its high affectability, reliability and anti-electromagnetic obstruction. This is known as chemical decomposition by-product method. A simulated coaxial deterioration chamber was designed and used on the high voltage electrode to re-enact the decomposition of SF6 under the impact of protrusion defect that generates partial discharge in the coaxial chamber at a pressure of 0.2MPa.The chamber is energised at 50kv for the period of 50 hours and the generated partial discharge simulate the decomposition of SF6 gas. The deterioration decomposition products SO2, SOF2, SO2F2, SO2F10, SiF4, CO, C3F8, C2F6 were detected offline by FTIR spectrometer. These deteriorated items and its concentration can be utilized to recognize and distinguish the type and the magnitude of fault in gas insulated switchgear (protrusion fault) before failure occur for the aim of preventive maintenance.

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Margalit, Eyal, Daniel Bahir, and Haneen Jabaly-Habib. "Using a commercial fibrin sealant (TISSEEL) as an adjuvant for full-thickness macular hole closure surgery: A case series." Indian Journal of Ophthalmology - Case Reports 3, no. 3 (2023): 772–75. http://dx.doi.org/10.4103/ijo.ijo_643_23.

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A retrospective interventional case series was performed to evaluate the anatomical and visual outcomes of macular hole surgery aided with TISEEL commercial fibrin sealant. Seven eyes of seven patients were included: three with a recurrent macular hole, one with a traumatic macular hole, and three with primary macular holes. All eyes underwent vitrectomy, internal limiting membrane peeling, fluid air exchange, instillation of 1–2 drops of the commercial fibrin sealant on the hole, and C3F8 gas injection. The macular hole was closed in all seven patients; they showed significant improvement in visual acuity and no ocular or systemic complications.

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Narayan, N., and M. S. Sridhar. "Perfluropropane (C3F8) gas injection followed by deep anterior lamellar keratoplasty (DALK) in severe keratoconus." Eye 28, no. 10 (2014): 1260–61. http://dx.doi.org/10.1038/eye.2014.159.

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LU, DA-WEN, MING-CHEN TAI, and CHIAO-HSI CHIANG. "Subconjunctival Retention of C3F8 Gas Increased the Success Rates of Trabeculectomy in Young People." Journal of Ocular Pharmacology and Therapeutics 13, no. 3 (1997): 235–42. http://dx.doi.org/10.1089/jop.1997.13.235.

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KIM, SUNG SOO, WILLIAM E. SMIDDY, WILLIAM J. FEUER, and WEI SHI. "OUTCOMES OF SULFUR HEXAFLUORIDE (SF6) VERSUS PERFLUOROPROPANE (C3F8) GAS TAMPONADE FOR MACULAR HOLE SURGERY." Retina 28, no. 10 (2008): 1408–15. http://dx.doi.org/10.1097/iae.0b013e3181885009.

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Journal articles on the topic 'C3F8 gas'

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