AIM:To investigate the incidence and the predisposing factors of anterior chamber(AC)gas bubbles during femtosecond laser(FS)flap creation for laser in situ keratomileusis(LASIK).METHODS:All patients who underwent FS-...AIM:To investigate the incidence and the predisposing factors of anterior chamber(AC)gas bubbles during femtosecond laser(FS)flap creation for laser in situ keratomileusis(LASIK).METHODS:All patients who underwent FS-LASIK surgery at CMU LASIK Center between January 2013 and May 2016 were retrospective reviewed.Preoperative and intraoperative data including keratometry,white-towhite(WTW)corneal diameter,flap parameters(diameter,thickness,hinge position,and tunnel length)and pulse energy were reviewed and compared between incident group and control group.To determine the risk factors,univariate and multivariate conditional logistic regression were used;the eye was unit of analysis.RESULTS:The incidence of AC gas bubbles was 1.6%(22 out of 1378 eyes).The median WTW in the AC bubbles group was 11.5 mm(range 11.1-12.1),which was significantly different from the control group(11.7 mm,range 10.5-12.8,P=0.021).The result of the median WTW minus the flap diameter in the AC bubbles group was 2.5 mm(range 2.1-3.2),which was statistically different to the control group(2.7 mm,range 1.5-3.8,P=0.008).The logistic regression analysis showed that the result of the WTW minus the flap diameter in the AC bubbles group had an adjusted odds ratio of 0.204(95%CI;0.056-0.747,P=0.016).CONCLUSION:Development of AC gas bubbles during FS flap creation is not an uncommon event in Asian eyes which typically have a small WTW.The flap diameter when adjusted relatively to the WTW is a predisposing factor to the possibility of AC gas bubbles occurrence.展开更多
Formaldehyde is an air toxic that is typically emitted from natural gas-fired internal combustion engines as a product of incomplete combustion. The United States Environmental Protection Agency (EPA) regulates air to...Formaldehyde is an air toxic that is typically emitted from natural gas-fired internal combustion engines as a product of incomplete combustion. The United States Environmental Protection Agency (EPA) regulates air toxic emissions, including formaldehyde, from stationary reciprocating internal combustion engines. National air toxic standards are required under the 1990 Clean Air Act Amendments. This work investigates the effect that hardware modifications, or retrofit technologies, have on formaldehyde emissions from a large bore natural gas engine. The test engine is a Cooper-Bessemer GMV-4TF two stroke cycle engine with a 14” (35.6 cm) bore and a 14” (35.6 cm) stroke. The impact of modifications to the fuel injection and ignition systems are investigated. Data analysis and discussion is performed with reference to possible formaldehyde formation mechanisms and in-cylinder phenomena. The results show that high pressure fuel injection (HPFI) and precombustion chamber (PCC) ignition significantly reduce formaldehyde展开更多
A retrospective analysis was performed of patients who received a paracentesis immediately following an intravitreal injection of bevacizumab or triamcinolone acetonide.These patients were previously diagnosed as havi...A retrospective analysis was performed of patients who received a paracentesis immediately following an intravitreal injection of bevacizumab or triamcinolone acetonide.These patients were previously diagnosed as having glaucoma,ocular hypertension,or had responded previously with sustained elevated intraocular pressure.Of 1661 procedures were performed.Totally 219（13%） of the injections were on phakic patients.A median（SD） of 210 μL（40 μL） of aqueous was removed during each paracentesis.There were no reported incidences of any complications.We propose performing a paracentesis immediately following intravitreal injections for patients at risk for ocular hypertension,glaucoma,and retinal vein or artery occlusion.展开更多
目的:应用前房注入无菌空气治疗白内障手术结束时出现前房不稳定的情况,观察手术效果、并发症,评估安全性。方法:回顾性分析白内障手术结束时前房不稳定的病例,将其分成两组,注气组31眼为前房注气组,注液组27眼为注液(平衡盐溶液,BSS)组...目的:应用前房注入无菌空气治疗白内障手术结束时出现前房不稳定的情况,观察手术效果、并发症,评估安全性。方法:回顾性分析白内障手术结束时前房不稳定的病例,将其分成两组,注气组31眼为前房注气组,注液组27眼为注液(平衡盐溶液,BSS)组,观察前房气泡吸收情况及前房稳定性,对角膜内皮细胞、视力、眼压的影响,有无其它并发症如眼内炎症、黄斑囊样水肿。结果:两组术前眼压对比、术后眼压对比差异均无统计学意义(P>0.05),注气组术前眼压(15.29±0.53)mm Hg与术后1d眼压(14.58±0.63)mm Hg对比差异无统计学意义(P>0.05)。两组术前角膜内皮细胞密度对比(2435.71±194.80 vs 2 430.74±191.95个/mm2),术后角膜内皮细胞密度对比(2400.74±194.00 vs 2398.22±193.36个/mm2)差异均无统计学意义(P>0.05)。两组术后均未出现浅前房、眼内炎症。术中单次操作前房恢复稳定率注气组94%,注液组33%,两组对比差异具有统计学意义(P<0.05)。结论:应用前房注气治疗白内障术毕出现前房恢复不稳定情况,安全有效,简单快速。展开更多
文摘AIM:To investigate the incidence and the predisposing factors of anterior chamber(AC)gas bubbles during femtosecond laser(FS)flap creation for laser in situ keratomileusis(LASIK).METHODS:All patients who underwent FS-LASIK surgery at CMU LASIK Center between January 2013 and May 2016 were retrospective reviewed.Preoperative and intraoperative data including keratometry,white-towhite(WTW)corneal diameter,flap parameters(diameter,thickness,hinge position,and tunnel length)and pulse energy were reviewed and compared between incident group and control group.To determine the risk factors,univariate and multivariate conditional logistic regression were used;the eye was unit of analysis.RESULTS:The incidence of AC gas bubbles was 1.6%(22 out of 1378 eyes).The median WTW in the AC bubbles group was 11.5 mm(range 11.1-12.1),which was significantly different from the control group(11.7 mm,range 10.5-12.8,P=0.021).The result of the median WTW minus the flap diameter in the AC bubbles group was 2.5 mm(range 2.1-3.2),which was statistically different to the control group(2.7 mm,range 1.5-3.8,P=0.008).The logistic regression analysis showed that the result of the WTW minus the flap diameter in the AC bubbles group had an adjusted odds ratio of 0.204(95%CI;0.056-0.747,P=0.016).CONCLUSION:Development of AC gas bubbles during FS flap creation is not an uncommon event in Asian eyes which typically have a small WTW.The flap diameter when adjusted relatively to the WTW is a predisposing factor to the possibility of AC gas bubbles occurrence.
文摘Formaldehyde is an air toxic that is typically emitted from natural gas-fired internal combustion engines as a product of incomplete combustion. The United States Environmental Protection Agency (EPA) regulates air toxic emissions, including formaldehyde, from stationary reciprocating internal combustion engines. National air toxic standards are required under the 1990 Clean Air Act Amendments. This work investigates the effect that hardware modifications, or retrofit technologies, have on formaldehyde emissions from a large bore natural gas engine. The test engine is a Cooper-Bessemer GMV-4TF two stroke cycle engine with a 14” (35.6 cm) bore and a 14” (35.6 cm) stroke. The impact of modifications to the fuel injection and ignition systems are investigated. Data analysis and discussion is performed with reference to possible formaldehyde formation mechanisms and in-cylinder phenomena. The results show that high pressure fuel injection (HPFI) and precombustion chamber (PCC) ignition significantly reduce formaldehyde
文摘A retrospective analysis was performed of patients who received a paracentesis immediately following an intravitreal injection of bevacizumab or triamcinolone acetonide.These patients were previously diagnosed as having glaucoma,ocular hypertension,or had responded previously with sustained elevated intraocular pressure.Of 1661 procedures were performed.Totally 219（13%） of the injections were on phakic patients.A median（SD） of 210 μL（40 μL） of aqueous was removed during each paracentesis.There were no reported incidences of any complications.We propose performing a paracentesis immediately following intravitreal injections for patients at risk for ocular hypertension,glaucoma,and retinal vein or artery occlusion.
文摘目的:应用前房注入无菌空气治疗白内障手术结束时出现前房不稳定的情况,观察手术效果、并发症,评估安全性。方法:回顾性分析白内障手术结束时前房不稳定的病例,将其分成两组,注气组31眼为前房注气组,注液组27眼为注液(平衡盐溶液,BSS)组,观察前房气泡吸收情况及前房稳定性,对角膜内皮细胞、视力、眼压的影响,有无其它并发症如眼内炎症、黄斑囊样水肿。结果:两组术前眼压对比、术后眼压对比差异均无统计学意义(P>0.05),注气组术前眼压(15.29±0.53)mm Hg与术后1d眼压(14.58±0.63)mm Hg对比差异无统计学意义(P>0.05)。两组术前角膜内皮细胞密度对比(2435.71±194.80 vs 2 430.74±191.95个/mm2),术后角膜内皮细胞密度对比(2400.74±194.00 vs 2398.22±193.36个/mm2)差异均无统计学意义(P>0.05)。两组术后均未出现浅前房、眼内炎症。术中单次操作前房恢复稳定率注气组94%,注液组33%,两组对比差异具有统计学意义(P<0.05)。结论:应用前房注气治疗白内障术毕出现前房恢复不稳定情况,安全有效,简单快速。
