Case report: Advanced modified pneumatic retinopexy for treating simultaneous bilateral rhegmatogenous retinal detachment.

Background: Simultaneous bilateral rhegmatogenous retinal detachment (RRD) is a rare and challenging condition in ophthalmology. This case report focuses on a modified pneumatic retinopexy technique, designed to improve treatment outcomes for this difficult condition. Case presentation: A 59-year-old male presented with decreased visual acuity in his right eye for one week. Examination revealed extensive retinal detachment in the right eye with multiple superior breaks and macula off, separated by approximately 3 clock hours. The left eye exhibited one quartile of retinal detachment with superior breaks and macula on. Bilateral simultaneous PR was performed for retinal repair. In the modified PR procedure, 0.7 ml of low-concentration perfluoropropane and 0.7 ml of filtered pure air were intravitreally injected into the right and left eyes, respectively. A head position maneuver was then employed to sequentially close retinal breaks, followed by laser photocoagulation once the surrounding retina reattached. Two days after gas injection, both retinas were completely reattached. Best corrected visual acuity improved to 0.6 in the right eye and 0.9 in the left eye at the 8-month follow-up. Conclusion: The innovative modified pneumatic retinopexy technique presented in this case report offers a promising new approach for effectively treating simultaneous bilateral rhegmatogenous retinal detachment.

Impact of nanopore confinement on phase behavior and enriched gas minimum miscibility pressure in asphaltenic tight oil reservoirs.

Miscible gas injection in tight/shale oil reservoirs presents a complex problem due to various factors, including the presence of a large number of nanopores in the rock structure and asphaltene and heavy components in crude oil. This method performs best when the gas injection pressure exceeds the minimum miscibility pressure (MMP). Accordingly, accurate calculation of the MMP is of special importance. A critical issue that needs to be considered is that the phase behavior of the fluid in confined nanopores is substantially different from that of conventional reservoirs. The confinement effect may significantly affect fluid properties, flow, and transport phenomena characteristics in pore space, e.g., considerably changing the critical properties and enhancing fluid adsorption on the pore wall. In this study, we have investigated the MMP between an asphaltenic crude oil and enriched natural gas using Peng-Robinson (PR) and cubic-plus-association (CPA) equations of state (EoSs) by considering the effect of confinement, adsorption, the shift of critical properties, and the presence of asphaltene. According to the best of our knowledge, this is the first time a model has been developed considering all these factors for use in porous media. We used the vanishing interfacial tension (VIT) method and slim tube test data to calculate the MMP and examined the effects of pore radius, type/composition of injected gas, and asphaltene type on the computed MMP. The results showed that the MMP increased with an increasing radius of up to 100 nm and then remained almost constant. This is while the gas enrichment reduced the MMP. Asphaltene presence changed the trend of IFT reduction and delayed the miscibility achievement so that it was about 61% different from the model without the asphaltene precipitation effect. However, the type of asphaltene had little impact on the MMP, and the controlling factor was the amount of asphaltene in the oil. Moreover, although cubic EoSs are particularly popular for their simplicity and accuracy in predicting the behavior of hydrocarbon fluids, the CPA EoS is more accurate for asphaltenic oils, especially when the operating pressure is within the asphaltene precipitation range.

A comprehensive review direct methods to overcome the limitations of gas injection during the EOR process.

Among the Enhanced Oil Recovery (EOR) methods, gas-based EOR methods are very popular all over the world. The gas injection has a high ability to increase microscopic sweep efficiency and can increase production efficiency well. However, it should be noted that in addition to all the advantages of these methods, they have disadvantages such as damage due to asphaltene deposition, unfavorable mobility ratio, and reduced efficiency of macroscopic displacement. In this paper, the gas injection process and its challenges were investigated. Then the overcoming methods of these challenges were investigated. To inhibit asphaltene deposition during gas injection, the use of nanoparticles was proposed, which were examined in two categories: liquid-soluble and gas-soluble, and the limitations of each were examined. Various methods were used to overcome the problem of unfavorable mobility ratio and their advantages and disadvantages were discussed. Gas-phase modification has the potential to reduce the challenges and limitations of direct gas injection and significantly increase recovery efficiency. In the first part, the introduction of gas injection and the enhanced oil recovery mechanisms during gas injection were mentioned. In the next part, the challenges of gas injection, which included unfavorable mobility ratio and asphaltene deposition, were investigated. In the third step, gas-phase mobility control methods investigate, emphasizing thickeners, thickening mechanisms, and field applications of mobility control methods. In the last part, to investigate the effect of nanoparticles on asphaltene deposition and reducing the minimum miscible pressure in two main subsets: 1- use of nanoparticles indirectly to prevent asphaltene deposition and reduce surface tension and 2- use of nanoparticles as a direct asphaltene inhibitor and Reduce MMP of the gas phase in crude oil was investigated.

Sensitivity analysis for enhancing crude oil recovery with continuous flow gas lift: A study in reference to the porous media of the upper Assam basin, India.

Despite minimal formation damage or water-cut, the majority of oil wells in brown oil fields cease to flow naturally. The current study looks into and analyses what caused a self-flowing well in the upper Assam basin to become non-flowing. The non-flow condition of the well was investigated in the current work as a function of water cut, reservoir pressure, reservoir rock permeability, and GOR. The effect of WHP and WHT on these functions was investigated. This work incorporates innovative methodology that uses the PROSPER simulation model for assessing the possibility of establishing flowability in a dead well based on inflow (IPR) and vertical lift performance (VLP). Subsequent analysis was carried out to examine the scope of producing this dead well under continuous flow gas lift. For this, the current work first examined the tubing diameter and reservoir temperature as standalone parameters to find out if they have any role to play in the flowability of the dead well. Following this, sensitivity analysis was done taking four parameters into account, i.e., reservoir pressure, reservoir rock permeability, water cut, and total GOR. In the current work, surface equipment correlation was established using Beggs and Brill correlation, while vertical lift performance was established using correlation from Petroleum Expert. The results of the current work highlight that a well's production rate under continuous flow gas lift can be enhanced by employing an optimised gas injection rate. The findings of this work conclude that higher reservoir pressure enables an oil well to produce with a high water cut under a continuous flow gas lift system, provided there are no formation damage issues on the well.

The optical method based on gas injection overestimates leaf vulnerability to xylem embolism in three woody species.

Plant hydraulic traits related to leaf drought tolerance, like the water potential at turgor loss point (TLP) and the water potential inducing 50% loss of hydraulic conductance (P50), are extremely useful to predict the potential impacts of drought on plants. While novel techniques have allowed the inclusion of TLP in studies targeting a large group of species, fast and reliable protocols to measure leaf P50 are still lacking. Recently, the optical method coupled with the gas injection (GI) technique has been proposed as a possibility to speed up the P50 estimation. Here, we present a comparison of leaf optical vulnerability curves (OVcs) measured in three woody species, namely Acer campestre (Ac), Ostrya carpinifolia (Oc) and Populus nigra (Pn), based on bench dehydration (BD) or GI of detached branches. For Pn, we also compared optical data with direct micro-computed tomography (micro-CT) imaging in both intact saplings and cut shoots subjected to BD. Based on the BD procedure, Ac, Oc and Pn had P50 values of -2.87, -2.47 and -2.11 MPa, respectively, while the GI procedure overestimated the leaf vulnerability (-2.68, -2.04 and -1.54 MPa for Ac, Oc and Pn, respectively). The overestimation was higher for Oc and Pn than for Ac, likely reflecting the species-specific vessel lengths. According to micro-CT observations performed on Pn, the leaf midrib showed none or very few embolized conduits at -1.2 MPa, consistent with the OVcs obtained with the BD procedure but at odds with that derived on the basis of GI. Overall, our data suggest that coupling the optical method with GI might not be a reliable technique to quantify leaf hydraulic vulnerability since it could be affected by the 'open-vessel' artifact. Accurate detection of xylem embolism in the leaf vein network should be based on BD, preferably of intact up-rooted plants.

Review of Recent Advances in Gas-Assisted Focused Ion Beam Time-of-Flight Secondary Ion Mass Spectrometry (FIB-TOF-SIMS).

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is a powerful chemical characterization technique allowing for the distribution of all material components (including light and heavy elements and molecules) to be analyzed in 3D with nanoscale resolution. Furthermore, the sample's surface can be probed over a wide analytical area range (usually between 1 µm2 and 104 µm2) providing insights into local variations in sample composition, as well as giving a general overview of the sample's structure. Finally, as long as the sample's surface is flat and conductive, no additional sample preparation is needed prior to TOF-SIMS measurements. Despite many advantages, TOF-SIMS analysis can be challenging, especially in the case of weakly ionizing elements. Furthermore, mass interference, different component polarity of complex samples, and matrix effect are the main drawbacks of this technique. This implies a strong need for developing new methods, which could help improve TOF-SIMS signal quality and facilitate data interpretation. In this review, we primarily focus on gas-assisted TOF-SIMS, which has proven to have potential for overcoming most of the aforementioned difficulties. In particular, the recently proposed use of XeF2 during sample bombardment with a Ga+ primary ion beam exhibits outstanding properties, which can lead to significant positive secondary ion yield enhancement, separation of mass interference, and inversion of secondary ion charge polarity from negative to positive. The implementation of the presented experimental protocols can be easily achieved by upgrading commonly used focused ion beam/scanning electron microscopes (FIB/SEM) with a high vacuum (HV)-compatible TOF-SIMS detector and a commercial gas injection system (GIS), making it an attractive solution for both academic centers and the industrial sectors.

Simultaneous intravitreal aflibercept and gas injections for submacular hemorrhage secondary to polypoidal choroidal vasculopathy.

PURPOSE: To investigate the outcomes of intravitreal aflibercept and gas injections for submacular hemorrhage (SMH) associated with polypoidal choroidal vasculopathy (PCV). METHODS: We retrospectively reviewed the medical records of 22 eyes with SMH secondary to PCV that underwent intravitreal aflibercept and 100% perfluoropropane (0.3-0.5 mL) followed by 3-day prone positioning from August 2013 through November 2020. The primary outcome measure was best-corrected visual acuity (BCVA) at 12 months. RESULTS: The average SMH size was 13.0 ± 9.7 (range, 2.0-37.8) disc diameter. The complete, partial, and no displacement of the SMH was observed in 8 (36%) eyes, 9 (41%) eyes, and 5 (23%) eyes, respectively. The BCVA (logarithm of the minimum angle of resolution) continuously improved significantly from 0.81 ± 0.41 (Snellen equivalent, 20/125) at baseline to 0.48 ± 0.44 (20/60), 0.33 ± 0.39 (20/43), and 0.28 ± 0.45 (20/38), at 3, 6, and 12 months, respectively (P = 0.01 for 3 months; P < 0.001 for 6 and 12 months). The BCVA improved by 3 or more lines in 14 eyes (64%). Two eyes (9%) developed visually significant vitreous hemorrhage, and 1 (5%) eye developed rhegmatogenous retinal detachment; all were successfully treated with vitrectomy. The better BCVA at 12 months tended to be associated with lower height of the SMH at baseline (R2 = 0.171, P = 0.056) and a greater displacement of SMH (R2 = 0.244, P = 0.069). Worse BCVA at 12 months was associated with anticoagulant medication (P < 0.001). CONCLUSIONS: Intravitreal aflibercept and gas injections are effective and relatively safe for SMH associated with PCV, resulting in significant visual improvement.

Effects of Oxygen Gas Injection on the Subsequent Development of Chick Embryos in a Shell-Less Culture System.

The effects of oxygen gas injection starting on day 17 of incubation (D17) in a chick shell-less culture system (cSLC) on the subsequent embryo development were examined on day 19 of incubation (D19). On D19 of cSLC, the plasma phosphorus and total cholesterol concentrations of the embryos were significantly higher (P<0.05), while the plasma calcium concentrations were significantly lower (P<0.05) than those in the intact control (IC) group. However, no significant differences in embryo viability and other major blood component levels were observed among the experimental groups (P>0.05). The percutaneous oxygen saturation was lower in D17-cSLC embryos before oxygen gas supplementation than in the IC (P<0.05) embryos. Severe renal tubular degeneration of the metanephros was observed in D19-cSLC embryos despite oxygen gas injection starting from D17. These results indicate that D19-cSLC embryos are hypoxia even after injecting oxygen gas starting on D17.

Intravitreal gas injection for early persistent macular hole after primary pars plana vitrectomy.

PURPOSE: To report the clinical presentations and outcome of early intravitreal injection (IVI) of octafluoropropane (C3F8) for persistent macular holes (MH) after primary pars plana vitrectomy with the internal limiting membrane (ILM) peeling technique. METHODS: Nineteen eyes of 18 patients with persistent MH after vitrectomy underwent intravitreal injection of C3F8 between 11 and 21 days after the initial surgery (intravitreal gas injection group). Another nine eyes with a persistent MH without additional IVI C3F8 were included (non-intravitreal gas injection group). Best-corrected visual acuity (BCVA), optical coherence tomography (OCT) features including size and configuration of MH, and time duration between the 2 surgeries were compared between the MH closure and open groups. The closure rate of persistent MHs was compared between the intravitreal gas injection group and non-intravitreal gas injection group. RESULTS: Twelve of 19 eyes (63%) achieved MH closure after 1 to 3 times IVI C3F8. The final BCVA after vitrectomy and IVI gas was significantly better in the MH closure group (P = .005). Nine of 12 patients (75%) in the MH closure group had a visual acuity improvement of more than 2 lines. Original MHs with smaller minimal diameter, higher macular hole index (MHI) and higher tractional hole index (THI); and persistent MHs with smaller minimal diameter, higher THI, and lower diameter hole index (DHI) showed higher MH closure rate. None of the persistent MHs closed in the non-intravitreal gas injection group (0/9 eyes). CONCLUSION: Early intravitreal injection of C3F8 can be a cost-effective first-line treatment for early persistent MHs after primary surgery, especially in eyes with favorable OCT features.

Experimental Study on the Time-Dependent Characteristics of MLPS Transparent Soil Strength.

The time-dependent characteristics of transparent soil strength, composed of magnesium lithium phyllosilicate, is important for applying a thixotropic clay surrogate. The gas injection method was employed to obtain the strength, represented as cracking pressure, which was then correlated to variables including rest time, disturbance time, and recovery time. Three concentrations (3, 4, and 5%) were tested. The results show that the strength was directly proportional to the rest time, recovery time, and concentration while the disturbance time reversed. The calculated limit strengths for 3%, 4%, and 5% transparent soils were 3.831 kPa, 8.849 kPa, and 12.048 kPa, respectively. Experimental data also showed that the residual strength for higher concentration transparent soil was more significant than the lower ones. The elastic property immediately generated partial strength recovery after disturbance, while the viscosity property resulted in a slow recovery stage similar to the rest stage. The strength recovery rate was also sensitive to concentration. Furthermore, the strength with 3%, 4%, and 5% concentrations could regain limit values after sufficient recovery, which were calculated as 4.303 kPa, 8.255 kPa, and 14.884 kPa, respectively.

A new control strategy to improve the mass transfer capacity and reduce air injection costs in raceway reactors.

Raceway reactors are still the most extensive technology for microalgae production. However, these reactors have some drawbacks, one of them being a low mass transfer capacity, which provokes dissolved oxygen accumulation and thus reduction of system performance. To overcome this problem, it is imperative to improve the photobioreactor design as well as the operating conditions. One solution is to maintain the dissolved oxygen below defined limits. In this work, a new control algorithm is proposed to improve the mass transfer capacity of raceway reactors while at the same time reducing air injection costs. The main idea of the proposed control approach is that only the necessary amount of airflow will be applied according to transfer capacity demand. This control strategy was first analyzed in simulation and compared with classical On/Off solutions, and subsequently evaluated in outdoor conditions in a photobioreactor of 80 m2.

Intra-vitreal gas injection and supine positioning for hypotony post-intrascleral intraocular lens fixation.

PURPOSE: This study aimed to report a case of intravitreal gas injection in the supine position for hypotony after intrascleral intraocular lens (IOL) fixation in a patient with Vogt-Koyanagi-Harada (VKH) disease. OBSERVATIONS: A 72-year-old Japanese female patient presented with blurred vision in her right eye. Both eyes exhibited a sunset glow fundus due to VKH disease. The right IOL was dislocated; therefore, IOL fixation was performed. The patient's hypotony and choroidal effusion persisted postoperatively and her intraocular pressure (IOP) remained 2-4 mmHg despite the performance of two steroid courses. C3F8 (perfluoro pane gas) was injected into the vitreous cavity on postoperative day 35. The patient was instructed to assume a supine position on the third day after injection. At 6 days post-injection, her IOP began to rise; her IOP remained within the normal range until 1 year later. CONCLUSIONS AND IMPORTANCE: This is the first report of successful intravitreal gas injection in a supinated patient with VKH disease to treat postoperative hypotony.

Effect of gas injection on cavitation-assisted plasma treatment efficiency of wastewater.

Underwater plasma has been long recognized as a "green" alternative to conventional chemicals in the wastewater treatment processes. However, practical application of underwater plasma is still challenging due to insufficient treatment performance. Recently, we proposed a novel process named ACAP utilizing acoustic cavitation in order to stabilize the plasma generation and to enlarge the plasma processing region. This work continues our investigation regarding the ACAP treatment process focusing on effects of gas injection. Experiments were performed using an ultrasonic installation equipped with a specially designed sonotrode (Diam. 48 mm) operated at a frequency of 20 kHz and acoustic power of 120 W. The results revealed that the degradation efficiency of Rhodamine B, which was used as a model wastewater pollutant, remains almost unchangeable in the case of air injection, but it is doubled when argon is injected into the ACAP reactor. It was found that the argon injection enhances the degradation efficiency significantly even without ultrasound irradiation. Results of additional measurements suggest that the effect of argon is attributed to its ability to yield high temperature during cavitation, comparatively good solubility in water and a better ability to reduce the breakdown voltage in water compared to the air case.

The Effect of High Protein Powder Structure on Hydration, Glass Transition, Water Sorption, and Thermomechanical Properties.

Poor solubility of high protein milk powders can be an issue during the production of nutritional formulations, as well as for end-users. One possible way to improve powder solubility is through the creation of vacuoles and pores in the particle structure using high pressure gas injection during spray drying. The aim of this study was to determine whether changes in particle morphology effect physical properties, such as hydration, water sorption, structural strength, glass transition temperature, and α-relaxation temperatures. Four milk protein concentrate powders (MPC, 80%, w/w, protein) were produced, i.e., regular (R) and agglomerated (A) without nitrogen injection and regular (RN) and agglomerated (AN) with nitrogen injection. Electron microscopy confirmed that nitrogen injection increased powder particles' sphericity and created fractured structures with pores in both regular and agglomerated systems. Environmental scanning electron microscopy (ESEM) showed that nitrogen injection enhanced the moisture uptake and solubility properties of RN and AN as compared with non-nitrogen-injected powders (R and A). In particular, at the final swelling at over 100% relative humidity (RH), R, A, AN, and RN powders showed an increase in particle size of 25, 20, 40, and 97% respectively. The injection of nitrogen gas (NI) did not influence calorimetric glass transition temperature (Tg), which could be expected as there was no change to the powder composition, however, the agglomeration of powders did effect Tg. Interestingly, the creation of porous powder particles by NI did alter the α-relaxation temperatures (up to ~16 °C difference between R and AN powders at 44% RH) and the structural strength (up to ~11 °C difference between R and AN powders at 44% RH). The results of this study provide an in-depth understanding of the changes in the morphology and physical-mechanical properties of nitrogen gas-injected MPC powders.

Cu Patterning Using Femtosecond Laser Reductive Sintering of CuO Nanoparticles under Inert Gas Injection.

In this paper, we report the effect of inert gas injection on Cu patterning generated by femtosecond laser reductive sintering of CuO nanoparticles (NPs). Femtosecond laser reductive sintering for metal patterning has been restricted to metal and metal-oxide composite materials. By irradiating CuO-nanoparticle paste with femtosecond laser pulses under inert gas injection, we intended to reduce the generation of metal oxides in the formed patterns. In an experimental evaluation, the X-ray diffraction peaks corresponding to copper oxides, such as CuO and Cu2O, were much smaller under N2 and Ar gas injections than under air injection. Increasing the injection rates of both gases increased the reduction degree of the X-ray diffraction peaks of the CuO NPs, but excessively high injection rates (≥100 mL/min) significantly decreased the surface density of the patterns. These results qualitatively agreed with the ratio of sintered/melted area. The femtosecond laser reductive sintering under inert gas injection achieved a vacuum-free direct writing of metal patterns.

Management of acute corneal hydrops with intracameral gas injection.

PURPOSE: To report two cases of severe acute corneal hydrops that were resolved by intracameral gas injection alone. OBSERVATIONS: Case 1 is a 27-year-old woman with bilateral severe keratoconus who developed sequential acute corneal hydrops in the right eye followed by the left eye that were each successfully treated using intracameral 20% sulfur hexafluoride gas injection. Case 2 is a 62-year-old man that developed a large fluid cleft beneath a pre-existing LASIK flap, which resolved with intracameral 20% sulfur hexafluoride gas injection without the need for corneal transplantation. CONCLUSIONS AND IMPORTANCE: In acute corneal hydrops, intracameral gas injection to tamponade Descemet's membrane tears with decompression of stromal fluid can be an effective intervention to delay or avoid keratoplasty in individuals whose corneal hydrops does not improve with conventional medical management.

A Case of Pneumatic Displacement with Gas Tamponade Performed for Macular Subretinal Hemorrhage Complicating Vogt-Koyanagi-Harada Disease.

We experienced a case of subretinal hemorrhage (SRH) from choroidal neovascularization (CNV) complicating Vogt-Koyanagi-Harada disease (VKH) that underwent pneumatic displacement of hematoma by intravitreal gas injection. A 76-year-old male revealed VKH relapses and optical coherence tomography showed irregular retinal pigment epithelium in his right eye and serous retinal detachment and retinal pigment epithelial detachment in his left eye. Fluorescein angiography of the left eye showed hyperfluorescence possibly attributable to CNV. One month later, SRH occurred in the left eye, yet it was spontaneously absorbed. However, approximately 1 year later, the SRH recurred in the left eye affecting a wide area, including the macular region, and his visual acuity (VA) decreased to 0.06. When pneumatic displacement of the hematoma by intravitreal gas injection was performed, the SRH was inferiorly displaced, and his VA improved to 0.4. Pneumatic displacement with gas tamponade was effective for treating a case of SRH caused by persistent CNV complicating VKH.

Three-phase flow displacement dynamics and Haines jumps in a hydrophobic porous medium.

We use synchrotron X-ray micro-tomography to investigate the displacement dynamics during three-phase-oil, water and gas-flow in a hydrophobic porous medium. We observe a distinct gas invasion pattern, where gas progresses through the pore space in the form of disconnected clusters mediated by double and multiple displacement events. Gas advances in a process we name three-phase Haines jumps, during which gas re-arranges its configuration in the pore space, retracting from some regions to enable the rapid filling of multiple pores. The gas retraction leads to a permanent disconnection of gas ganglia, which do not reconnect as gas injection proceeds. We observe, in situ, the direct displacement of oil and water by gas as well as gas-oil-water double displacement. The use of local in situ measurements and an energy balance approach to determine fluid-fluid contact angles alongside the quantification of capillary pressures and pore occupancy indicate that the wettability order is oil-gas-water from most to least wetting. Furthermore, quantifying the evolution of Minkowski functionals implied well-connected oil and water, while the gas connectivity decreased as gas was broken up into discrete clusters during injection. This work can be used to design CO2 storage, improved oil recovery and microfluidic devices.

Functional and thermal properties of yellow pea and red lentil extrudates produced by nitrogen gas injection assisted extrusion cooking.

BACKGROUND: There are excellent opportunities for greater incorporation into our diets of pulses, which are rich in proteins and dietary fibers, if their functional properties are modified to fit a wide range of applications in the food industry. The objective of this research was to produce high protein and fiber extrudates from yellow pea and red lentil flours using conventional and N2 gas injection assisted extrusion cooking methods. The effects of process variables on extrudate functional and thermal properties were also investigated. RESULTS: The cold viscosity of extrudates produced by N2 gas injection were higher than those produced by conventional extrusion, indicating that gas-assisted extrusion does affect the end-product pasting properties. At higher barrel temperatures (150-175 °C) extrudates did not exhibit any thermal transition in their thermograms, and thus their starches were completely gelatinized and proteins completely denatured during extrusion. In general, water solubility of extrudates produced by N2 gas injection was significantly (P < 0.05) higher than those produced by conventional extrusion. Emulsion capacity and stability of yellow pea extrudates were in the range of 44-50% and 42-47%, respectively, and the counterpart values of red lentil extrudates were very similar (in the range of 43-47% and 43-46%, respectively). CONCLUSION: Nitrogen gas injection assisted extrusion cooking can be used practically in development of pulse extrudates which contain high protein and dietary fiber. This novel and innovative technique is a reliable alternative method to the conventional CO2 gas injection assisted extrusion cooking methods in the snack food and food ingredient industries. © 2019 Society of Chemical Industry.

Office-based intravitreal injection of expansile gas for management of macular hole in previously vitrectomized eyes.

PURPOSE: To report the successful closure of full-thickness macular hole (MH), using an office-based intravitreal gas injection, in two eyes having undergone prior pars plana vitrectomy (PPV). OBSERVATIONS: Patient 1 presented with acute loss of visual acuity to 20/300 in the left eye 5 months following PPV for fovea-off rhegmatogenous retinal detachment; MH was confirmed by examination and optical coherence tomography (OCT). 0.6 cc of 100% C3F8 gas was injected, with subsequent MH closure following one week of face-down positioning. Patient 2 presented with right eye visual acuity of 20/60 one month following PPV for optic nerve pit-associated maculopathy; MH was confirmed by examination and OCT. 0.85 cc of 100% C3F8 gas was injected in the office, with subsequent MH closure following one week of face-down positioning. CONCLUSIONS AND IMPORTANCE: MH management in previously vitrectomized eyes has traditionally been repeat PPV with internal limiting membrane peeling, fluid-air exchange, and expansile gas exchange. Intravitreal gas injection, in an office-based setting, is a viable clinical approach to close MH in some previously vitrectomized eyes.