Microbiologic analysis of aqueous humor in phacoemulsification.

PURPOSE: This study was designed as a microbiologic survey of the fluids aspirated from the anterior chamber at the end of cataract extraction performed by phacoemulsification, and to correlate the contamination rate of the anterior chamber to the surgical technique used. METHODS: One hundred and one consecutive patients (126 eyes) who underwent cataract extraction by phacoemulsification and posterior chamber intraocular lens implantation were included in the study. Microscopical examination, culture, and determination of the number of colonies were carried out on the bacteria and fungi in the anterior chamber fluids aspirated at the end of surgery, before final suture placement. RESULTS: Anterior chamber fluids yielded positive cultures in nine specimens (8.14%), six of which were identified as coagulase-negative staphylococci. Quantification disclosed colony counts ranging between 2-10 and 10-40 per mL. CONCLUSIONS: Preliminary results in a small population show that the contamination of the aqueous humor is significantly less frequent if the cataract extraction is performed by phacoemulsification.     

糖尿病白内障人工晶状体植入术临床分析

目的分析基层医院开展糖尿病白内障摘出联合后房型人工晶状体植入术的临床疗效。方法我们对46例(46眼)糖尿病白内障行现代囊外摘出联合后房型人工晶状体植入术，并设46例(46眼)老年性白内障患者行现代囊外摘出联合后房型人工晶状体植入术为对照。结果糖尿病白内障术后角膜内皮水肿、房水浑浊、纤维素样渗出、瞳孔后粘连、后囊浑浊等眼前段手术并发症发生率高于老年性白内障，但经正确有效处理，总体预后两组并无显著差异。结论糖尿病患者空腹血糖控制在8．0mmol／L以下，行白内障摘出后房型人工晶状体植入是安全的。     

白内障术后眼内炎的治疗分析

目的：探讨白内障术后眼内炎的治疗方案及效果。方法：对我院2006-01/2010-12白内障摘除术＋人工晶状体植入术的21973例28722眼患者的资料（超声乳化20937例27521眼,囊外摘除术1036例1201眼）进行回顾性分析。结果：在全部术眼中,感染性眼内炎11眼,感染率为0.04%,9眼发生于超声乳化术后,2眼发生于白内障囊外摘除术后。共有5眼病原菌培养阳性,其中表皮葡萄球菌2眼,金黄色葡萄球菌,浅绿色气球菌,真菌各1眼。感染发生于白内障术后2wk以内者占73%（8/11）,房水混浊或前房积脓者行前房灌洗＋玻璃体腔注射万古霉素;前房积脓合并明显玻璃体混浊或经前房灌洗＋玻璃体腔注射万古霉素治疗观察1～2d感染加重者行前房灌洗＋玻璃体切割术。治疗后11眼均保住眼球。结论：白内障术后眼内炎经常发生于白内障术后2wk以内,经及时有效的治疗可控制感染发展,保留部分有用视力;前房灌洗＋玻璃体腔注射万古霉素必要时联合玻璃体切割术是有效的治疗方法。     

白内障后囊破裂人工晶状体睫状沟固定与植入前房疗效比较

目的:比较睫状沟缝线固定人工晶状体术和前房人工晶状体植入术治疗白内障后囊破裂的疗效。方法:回顾性分析采用睫状沟缝线固定人工晶状体术、前房人工晶状体植入术治疗白内障后囊破裂45例45眼,比较两组手术的疗效。结果:睫状沟缝线固定人工晶状体术组和前房人工晶状体植入术组均能有效治疗白内障后囊破裂。但后者术后有2例6mo后出现虹膜睫状体炎及眼压升高,其余视力均改善。前者视力均改善,未见有明显的并发症。结论:睫状沟缝线固定人工晶状体术和前房人工晶状体植入术均能有效治疗白内障后囊破裂,改善视力,但前者更接近于生理位置,术后并发症更少。     

抗青光眼术后浅前房的前房重建手术

目的 探讨青光眼滤过术后浅前房的手术方法和效果.方法 取17例抗青光眼术后浅前房患者经保守治疗无效,有7只眼发生脉络膜脱离,5只眼行脉络膜上腔放液+前房成形术,1只眼行白内障超声乳化及人工晶状体植入术及前房成形术,1只眼行脉络膜上腔放液+白内障超声乳化及人工晶状体植入术+前部玻璃体切割术+前房成形术.有9只眼发生恶性青光眼,1例行抽玻璃体水囊联合前房成形术,3例行前部玻璃体切除及后囊切开联合小梁切除及丝裂霉素联合白内障超声乳化及人工晶状体植入及房角分离术,1例行前部玻璃体切除术中发生脉络膜脱离及脉络膜上腔出血行前部玻璃体切除联合玻璃体腔放液,2只眼行前部玻璃体切除联合白内障超声乳化及人工晶状体植入及房角分离术,1例行前部玻璃体切除联合前房成形术,术后前房仍浅又行白内障超声乳化及人工晶状体植入及后囊膜切开及房角分离术,1例为视网膜脱离术后硅油存留眼行白内障超声乳化联合虹膜周边切除术及前房成形术.结果 术后前房恢复时间脉络膜脱离组行脉络膜上腔放液及前房成形术平均为5.6d,恶性青光眼组行白内障超声乳化及人工晶状体植入术联合前部玻璃体切除及后囊切开组前房恢复时间最短,平均为1.1d.结论 恶性青光眼组行白内障超声乳化及人工晶状体植入术联合前部玻璃体切除及后囊切开治疗有效快速.     

Bacterial contamination of anterior chamber during IOL surgery

PURPOSE: To study the nature and frequency of bacterial contamination during cataract surgery. METHODS: The preoperative smears from the conjunctiva and anterior chamber (AC) fluid aspirates during extra-capsular cataract surgery (ECCE) with posterior chamber intraocular lens (PCIOL) implantation in 40 eyes were analysed for aerobic and anaerobic bacteria. Any change in the bacterial strains isolated before and after cataract surgery was also studied. RESULTS: AC fluid aspirates were positive for bacteria in 15 eyes (37.5%). Coagulase-negative Staphylococcus was the most common aerobe (39.4%) and Propionibacterium acnes the most common anaerobe. Of the 15 cases with positive AC fluid cultures, 6 showed an organism in the AC aspirate different from the conjunctival smear. CONCLUSION: Clinically there was no endophthalmitis in any of the eyes. Factors such as preoperative antibiotic use, the antibacterial properties of aqueous, or low inoculum size could explain this. The preoperative conjunctival smear may not be useful in predicting the AC fluid contamination or outcome of cataract surgery.     

青光眼巩膜瓣与超声乳化白内障巩膜隧道一体式三联术有效性探讨

目的：探讨不同进展时期的青光眼合并白内障采用青光眼巩膜瓣与超声乳化白内障巩膜隧道切口一体式三联手术的临床效果。

方法：对31例55眼青光眼合并白内障患者采用巩膜瓣联合巩膜隧道切口行三联手术,对比术前术后视力、眼压、滤过泡、术后并发症。

结果：术后6mo,视力较术前均有明显提高,眼压得到控制,滤过泡弥漫,术后并发症少。

结论：成熟的超声乳化人工晶状体植入术联合抗青光眼手术建立新的房水引流通道,能有效降低眼压,加深前房和快速提高视力,减少了单纯青光眼手术引起的各种并发症。     

Cataract,phacoemulsification and intraocular pressure: Is the anterior segment anatomy the missing piece of the puzzle?

Cataract extraction is a safe and effective surgery that has a lowering effect on the intraocular pressure. The specific mechanisms for this effect are still unclear. A direct inflammatory effect on the trabecular meshwork, alteration of the blood aqueous barrier, changes in the ciliary body and mechanical changes of the anterior segment anatomy are the key to understand cataract surgery and it's effects on aqueous humor dynamics. Additionally, with the advent of AS OCT, changes in the anterior segment of the eye have been studied and several parameters (such as lens vault, angle opening distance and anterior chamber depth) have been identified as predictors of intraocular pressure change. In eyes with narrow angles there is a greater drop in intraocular pressure after cataract surgery and it is correlated with parameters related to anterior chamber space. It is safe to affirm that cataract surgery is an important part of the modern glaucoma treatment and evidence should be analyzed as part of a bigger picture in order to more accurately understand its clinical relevance.     

Anterior chamber contamination during phacoemulsification and manual small-incision cataract surgery

PURPOSE: To compare the per-operative contamination of anterior chamber among eyes undergoing manual small-incision cataract surgery (MSICS) and phacoemulsification (PE). DESIGN: Prospective, randomized, interventional clinical trial. METHODS: In this study conducted at a tertiary-care center in southern India, 150 eyes undergoing cataract surgery were randomly allocated to undergo MSICS (group A, 75 eyes) and PE (group B, 75 eyes). Aqueous samples were taken before and at the end of surgery. Collected material was subjected to standard microbiological analysis. No preoperative antibiotics were used, but povidone-iodine 5% drops were instilled before surgery. Main outcome measures studied were the incidence of positive cultures in aqueous samples obtained from eyes in both groups. RESULTS: The incidence of anterior chamber contamination in the MSICS group (4%) did not significantly differ from the PE group (2.7%; P = .65). CONCLUSIONS: Incidence of anterior chamber contamination is similar among eyes undergoing MSICS and PE.     

Prospective evaluation of external ocularmicrobial growth and aqueous humor contamination during cataract surgery

Purpose:To analyze the route of aqueous humor contamination leading to thedevelopment of postoperative endophthalmitis.Setting:Department of Ophthalmology, University of Helsinki, Finland.Methods:Forty-nine eyes of 49 patients (31 having phacoemulsification and 18 extracapsularcataract extraction [ECCE]) participated in the study. Four bacterial cultures were taken: preoperative conjunctival swab, lid margin culture, intraoperative lacrimal lake sample, and immediate postoperative anterior chamber fluid sample.Results:Preoperative lid margin cultures were positive in 59.2% of eyes, conjunctival cultures in 69.4%, and lacrimal lake cultures in 24.9%. Four aqueous humor samples (8.2%) showed bacterial growth in the anterior chamber aspirate: 3 in the phacoemulsification and 1 in the ECCE group. The bacteria isolated in this study, Staphylococcus epidermidis and Propionibacterium acnes (2 positive isolates each) were sensitive to the preoperative topical antibiotics used. No aqueous humor sample or any from other locations showed gram-negative microbe growth. The most frequently recovered microbes in all samples collected from the 3 other sources were S epidermidis and other coagulase-negative staphylococcus species, followed by P acnes and other propionibacterium species, Staphylococcus aureus, and diptheroids.Conclusion:The ocular surface significantly contributed fo the transmission ofmicrobes into the eye during cataract surgery. These microbes could not be eradicated by topical preoperative antibiotics. However, no patient developed postoperative endophthalmitis. Natural defense mechanisms appear to fend off a minor inoculum with these microbes of relatively low pathogenicity.     

Microbiological profile of anterior chamber aspirates following uncomplicated cataract surgery

Anterior chamber aspirate cultures were done for 66 patients who underwent either an uncomplicated intracapsular cataract extraction, extracapsular cataract extraction with posterior-chamber intraocular lens implantation, or phacoemulsification with posterior-chamber intraocular lens implantation. The aspirate was obtained at the time of wound closure. The aspirates were immediately transferred to the microbiology laboratory where one drop of the aspirate was placed on a glass slide for gram stain, and the remainder was unequally divided and inoculated into blood agar, chocolate agar and thioglycolate broth. The cultures were incubated at 37 degrees C with 5% CO2 and held for 5 days. Of 66 patients 4 (6%), had smear-positive anterior chamber aspirates. None of the aspirates showed any growth on any of the 3 culture media used. None of the eyes in the study developed endophthalmitis. This study concludes that there is no contamination of the anterior chamber by viable bacteria after cataract surgery, irrespective of the mode of intervention.     

新型前房型人工晶状体一期二期植入临床观察

目的：评价新型弹性开放襻前房型人工晶状体一期或二期植入的临床效果。方法：共34只眼,一期前房型人工晶状体植入19只眼,其中老年性白内障12只眼,外伤性昌状体半脱位4只眼,外伤性白内障3只眼;二期植入15只眼,其中老年性白内障术后8只眼,外伤性白内障术后7只眼。术后随访半年以上。结果：一期植入术后68.4%(13只）眼视力≥0.5,其中≥1.0有3只眼,占15.8%,二期植术术后73.3%(11只眼）视力≥0.5,其中≥1.0有4只眼,占26.7%;术后常见并发症为角膜水肿的眼压升高。结论：新型弹性开放襻前房型人工晶状体一期二期植入均安全、有效。     

青光眼滤过术后浅前房的前房重建手术

目的探讨青光眼滤过术后浅前房的前房重建手术时机及手术方法。方法34例（36眼）浅前房（包括无前房）者中23眼行脉络膜上腔放液联合前房注气；8眼行玻璃体水囊抽液联合前房注气；2眼行玻璃体水囊抽液联合白内障囊外摘出及后房型人工晶状体植入；3眼行前房角分离、前房形成、小梁切除联合囊外摘出或人工晶状体植入。结果36眼中33眼在浅前房发生2周内手术，2月、4月、9月手术各1眼。其中30眼一次手术成功；3眼脉络膜上腔放液联合前房注气者经原角膜穿刺口进行了二次注气成功；2眼行玻璃体水囊抽液联合前房注气后前房仍不能形成改行其它手术方式成功；1眼前房角分离、前房形成、小粱切除联合囊外摘出术者手术失败。结论青光眼滤过术后Ⅱ度浅前房保守治疗最长不要超过2周，无效时须考虑前房重建手术；Ⅲ度浅前房一旦发生应立即手术。根据浅前房原凶要选择不同的手术或进行多手术联合。     

Bacterial contamination of the anterior chamber during phacoemulsification cataract surgery

PURPOSE: To determine the incidence of bacterial contamination of the anterior chamber after phacoemulsification cataract surgery with intraocular lens (IOL) implantation. SETTING: Department of Ophthalmology, Royal Prince Alfred Hospital, Sydney, Australia. METHODS: Ninety-eight consecutive eyes of 96 patients having phacoemulsification cataract surgery with IOL implantation were included in this prospective study. Two intraoperative anterior chamber aspirates were obtained from each patient, 1 taken at the start and the other at the conclusion of surgery. In addition, preoperative and postoperative conjunctival swabs were acquired. The 4 specimens were cultured using direct culturing techniques under aerobic and anaerobic conditions for 14 days. No preoperative antibiotics were used. RESULTS: The incidence of intraoperative anterior chamber contamination was 0% (95% confidence interval, 0%-3.7%) as all intraoperative anterior chamber samples proved culture negative. Sixty-five percent of the preoperative conjunctival swabs were positive for growth, with corynebacteria, coagulase-negative staphylococci, and Propionibacterium acnes being the most frequently cultured organisms. Sixteen percent of the postoperative conjunctival swabs were positive for growth, with corynebacteria and coagulase-negative staphylococci being the most common bacteria. One patient developed culture-positive postoperative endophthalmitis; using pulsed-field gel electrophoresis for further typing, the implicated Staphylococcus epidermidis was indistinguishable from that isolated from the patient's preoperative conjunctival swab. CONCLUSIONS: The bacterial contamination rate of the anterior chamber after phacoemulsification and IOL implantation was extremely low. Additional findings support the conjunctiva as being a primary source of bacteria causing postoperative endophthalmitis as well as the ability of povidone-iodine to reduce the conjunctival bacterial load.     

Evaluation of bacterial contamination rate of the anterior chamber during phacoemulsification surgery using an automated microbial detection system

AIM:To assess the incidence of anterior chamber bacterial contamination during phacoemulsification surgery using an automated microbial detection system (BacT/Alert).METHODS:Sixty-nine eyes of 60 patients who had uneventful phacoemulsification surgery, enrolled in this prospective study. No prophylactic topical or systemic antibiotics were used before surgery. After antisepsis with povidone-iodine, two intraoperative anterior chamber aqueous samples were obtained, the first whilst entering anterior chamber, and the second at the end of surgery. BacT/Alert culture system was used to detect bacterial contamination in the aqueous samples.RESULTS: Neither aqueous samples obtained at the beginning nor conclusion of the surgery was positive for microorganisms on BacT/Alert culture system. The rate of bacterial contamination during surgery was 0%. None of the eyes developed acute-onset endophthalmitis after surgery.CONCLUSION:In this study, no bacterial contamination of anterior chamber was observed during cataract surgery. This result shows that meticulous surgical preparation and technique can prevent anterior chamber contamination during phacoemulsification cataract surgery.     

超声乳化治疗特殊类型白内障技术分析

目的：探讨超声乳化术治疗特殊类型白内障的安全性和有效性。

方法：回顾性分析临床资料,研究超声乳化吸出(联合)人工晶状体植入术治疗青光眼术后白内障、小瞳孔白内障、葡萄膜炎并发白内障和外伤后并发白内障等特殊类型白内障的技术要领。

结果：进行治疗的73例84眼特殊类型白内障患者中,单纯行超声乳化术27例28眼,植入后房型人工晶状体52眼,植入前房型人工晶状体4眼; 术后1mo平均眼压12.72±2.63mmHg,脱盲率99%,脱残率96%; 并发症发生率4%。

结论：特殊类型白内障手术难度大,超声乳化术切口小,可保留晶状体后囊膜和植入人工晶状体,是摘除特殊类型白内障的理想术式。     

Early post-phacoemulsification hypotony as a risk factor for intraocular contamination: in vivo model

PURPOSE: To observe cataract wound dynamics and determine the risk for intraocular contamination under induced conditions of early postoperative hypotony after anterior chamber decompression for high intraocular pressure (IOP) spikes after uneventful phacoemulsification surgery. SETTING: Department of Ophthalmology, Queen's Hospital, Burton-on-Trent, United Kingdom. METHODS: In a prospective case series, 30 patients were treated with anterior chamber decompression for elevated IOP (>35 mm Hg) 1 to 2 hours after uneventful phacoemulsification through clear corneal temporal incisions. A drop of 2% fluorescein was instilled in the conjunctival sac before aqueous release to study the ocular fluid movements during and after the decompression procedure. The patterns of fluorescein movement were observed and photographed under cobalt blue light. RESULTS: Fluorescein staining of the entire corneal tunnel was observed in all 30 eyes after decompression. An immediate fluorescein flare was observed in the anterior chamber after aqueous release in 24 eyes (80%) (P<.001). Observations over several seconds after decompression found a frank influx of fluorescein-stained fluid into the anterior chamber in 12 eyes (40%) (P<.001), giving rise to an "inverse Seidel's test." An intermittent ingress of fluorescein-stained fluid continued for several minutes after the procedure in 6 eyes (20%) (P<.05). CONCLUSIONS: An incompetence of clear corneal cataract wound with intraocular contamination was observed during the period of induced hypotony after anterior chamber decompression in the early post-phacoemulsification period.     

肝素修饰人工晶体植入在抗青光眼术后白内障超声乳化术中的应用

目的观察肝素表面修饰折叠型人工晶体植入对抗青光眼术后白内障超声乳化吸除术后前房炎症反应的影响。方法对60例(88眼)抗青光眼术后白内障患者施行超声乳化吸除术,所有病例随机植入肝素表面修饰折叠型人工晶体或蓝光滤过折叠型人工晶体。应用激光闪光细胞检测仪(Laserflarecellmeter,LFCM)测量并比较术前及术后1天、7天、30天及90天房水的平均闪辉值,以评价前房炎症反应。并观察术前后的视力、眼压及滤过泡和角膜内皮计数情况。结果(1)术前,二组患者房水闪辉值没有显著性差异,植入肝素表面修饰折叠型人工晶体者,手术后7天内的房水闪辉值均明显低于蓝光滤过折叠型人工晶体植入组,而术后30、90天时两种人工晶体植入者之间差异无显著性。两组术后视力均明显提高,眼压控制稳定,角膜内皮功能正常。结论抗青光眼术后白内障手术后眼血-房水屏障功能受损,植入肝素表面修饰折叠型人工晶体能显著减轻白内障术后短期内的炎症反应,增加了手术安全性。     

Cathepsin A activity in the aqueous humor in patients with cataract, absolute glaucoma and intraocular tumors]

PURPOSE: To evaluate cathepsin A activity in the aqueous humor of patients with cataract, absolute glaucoma and intraocular tumors. MATERIAL AND METHODS: The studies were performed on human aqueous humor taken from anterior chamber of eye balls of patients operated because of cataract, absolute glaucoma and intraocular tumors. Cathepsin A activity was determined by the ninhydrin method with synthetic substrate (N-Cbz-Phe-Ala) at its optimum pH 5.0. RESULTS: In the human aqueous humor of the eye with cataract cathepsin A activity was more than three times higher than in the eye with choroid tumors and absolute glaucoma. No differences of enzyme activity in aqueous humor between patients with glaucoma and intraocular tumors were found. CONCLUSION: The increasing proteolytic activity of cathepsin A in aqueous humor of patients with cataract suggests its importance in cataract pathogenesis. This implies that cathepsin A is involved in development of lens opacity and is found in the aqueous humor due to diffusion from cataractous lens in which the proteolytic process prevails.     

Application of sustained delivery microsphere of cyclosporine A for preventing posterior capsular opacification in rabbits

AIM: To explore the inhibitory effect of a sustained cyclosporin A (CsA) delivery microsphere (CsA-MS) on posterior capsular opacification (PCO) in rabbit eyes after cataract extraction.METHODS: Twenty New Zealand white rabbits accepted cataract extraction plus intraocular lens implantation and their left eyes were intraoperatively injected CsA-MS prepared using polymer polylactioglycolic acid (PLGA) as a carrier and their right eyes were injected with empty MS. The changes in cornea, anterior chamber reaction, intraocular pressure, PCO and CsA concentration in aqueous humor were examined postoperatively and all the eyes were enucleated 3 months after surgery for histopathological and morphological examination with light microscopy and electron microscopy.RESULTS:Conjunctival hyperemia, corneal edema, intraocular pressure and anterior chamber response of experimental and control eyes were similar, while PCO in CsA-MS injected eyes was greatly improved compared with that in control eyes. Posterior capsules in CsA-MS injected eyes were smooth and lens epithelial cells (LEC) did not proliferate significantly (P>0.05), while LEC in posterior capsule of control eyes had different degrees of proliferation and cortical regeneration. LEC in CsA-MS injected eyes were not functionally active and underwent apoptosis, whereas LEC in control eyes were functionally active (F-test, P=0.025). In addition, the corneal ultrastructure showed no differences between CsA-MS and MS injected eyes.CONCLUSION: CsA-MS has high bioavailability in rabbit eyes and could inhibit postoperative PCO occurrence and development during the study period, suggesting that CsA-MS may be a promising, effective and safe administration route to prevent PCO in clinic.