小梁切除术术中房水滤过量与术中及术后早期眼压无关

目的 测量小梁切除术术中房水滤出量,并分析其与术中眼压和术后早期眼压之间的关系。设计 前瞻性观察性研究。研究对象 2009年12月-2010年8月初次接受小梁切除术的82例（82眼）青光眼患者。方法 （1）将不同体积的生理盐水加到泪液检测滤纸条上的指定位置,然后观察滤纸吸水长度与液体量之间的关系。（2）前瞻性纳入初次小梁切除术的青光眼患者,术者遵统一程序行标准小梁切除术,关闭巩膜瓣前房注水稳定后采用Tonopen测量术中眼压。术中在关闭巩膜瓣,前房注水后60 s将泪液检测滤纸条置于巩膜瓣口处测量房水滤出量,持续80 s。分析术中滤过量与术中眼压及术后第1日及第7日眼压之间的关系,并观察术后滤过泡隆起度、范围及并发症情况。主要指标 滤纸湿线长度,术中及术后早期眼压,滤过泡情况。结果 滤纸吸水长度与液体量具有显著相关性,液体的体积可根据滤纸上湿线的长度通过以下公式计算：吸液体积（μl）=1.0434×吸液长度（mm）+2.4086（R2= 0.97）。82例患者（82眼）术前眼压（32.3±9.0）mmHg。根据术中滤纸吸水长度,将患者分为3组：第一组患者的吸水长度≤5 mm（n=46）,第二组6~10 mm（n=18）,第三组≥11 mm（n=18）。三组患者术中眼压分别为（13.9±8.3）mmHg、（12.1±5.4）mmHg、（12.1±6.5）mmHg（P=0.543）。术后第1天三组的眼压分别为（13.3±7.9）mmHg、（12.7±7.3）mmHg、（15.9±9.0）mmHg;术后1周,三组眼压分别为（12.2±6.9）mmHg、（10.7±5.6）mmHg、（13.1±8.1）mmHg,三组间术后早期眼压及滤过泡情况差异均无统计学意义（P均>0.05）。术后未观察到浅前房等其他并发症。结论 滤纸吸水长度与滤出液体量具有显著相关性。小梁切除术术中的滤出量可通过泪液检测滤纸条定量测量。但不能通过术中滤过量这个因素直接判定术后早期的眼压。（眼科, 2014, 23： 94-98）     

原发性闭角型青光眼持续高眼压状态下的手术治疗

目的:探讨原发性闭角型青光眼持续高眼压下施行小梁切除术的手术要点及治疗效果.方法:对21例22眼急性闭角型青光眼持续高眼压状态患者,术前、术中用多种方法使眼压逐渐下降后,进行小梁切除术.结果:术后6～12 mo,22眼中有17眼术后不用抗青光眼药物,眼压能控制在21 mmHg(1 mmHg=0.133 kPa)以下,4眼加用降眼压药物眼压控制正常;19眼视力有所提高,无严重并发症.结论:对于应用药物治疗不能有效控制眼压的青光眼患者,应当机立断进行手术治疗.只要完善术前准备,术中精心操作,术后精心护理,高眼压下小梁切除术是必要、安全、有效的.     

The effect of scleral flap edge apposition on intraocular pressure control in experimental trabeculectomy

Background: To assess the contribution of scleral flap edge apposition to intraocular pressure (IOP) control in trabeculectomy, using a previously described and validated experimental model of guarded filtration surgery. Materials and methods: Twelve rectangular‐flap trabeculectomy operations each with two apical adjustable sutures were performed on six donor human eyes connected to a constant flow infusion with real‐time IOP monitoring. Three sizes of scleral flap were created: 4 × 4 mm, 16 mm² (n = 4), 3 × 3 mm, 9 mm² (n = 4) or 3 × 2 mm, 6 mm² (n = 4). Sutures were tied tightly to produce high aqueous outflow resistance, and equilibrium IOP established. The lateral and posterior edges of the scleral flap were removed, the sutures tightened again, and the new equilibrium IOP measured. Results: Following flap closure and with intact flap edges, the mean absolute IOP for all flaps (n = 12) was 19.5 ± 3.9 mm Hg (mean ± SD, range 12.4–27 mm Hg) and following flap edge excision 18.7 ± 4.4 mm Hg (range 5.6–27.9 mm Hg), demonstrating no significant difference between flaps with edge apposition compared with those without (P = 0.33). Mean relative IOP (% of baseline) was 68.4 ± 12.1% (range 40.9–94%) with intact flap edges and 65.4 ± 14.5% (range 18.5–97.2%) following flap edge excision (P = 0.31). Flaps measuring 4 × 4 mm and 3 × 3 mm behaved in a similar manner with minimal change in equilibrium IOP following excision of flap edges. Conclusions: In this experimental model, scleral flap edge apposition is not required for generating outflow resistance. Suture tension generated during tight flap closure produces apposition of the underside of the scleral trapdoor to the underlying bed, and it is this apposition, which determines IOP.     

持续高眼压下行复合式小梁切除术的临床观察

目的探讨持续性高眼压状态下行复合式小梁切除术的安全性、可行性及疗效。方法对36例（40眼）眼压控制不良的青光眼进行了前、后房穿刺联合复合式小梁切除术。术后观察视力、眼压、前房深度,以及前房积血等并发症的情况。结果所有病例手术过程顺利,无出现脉络膜下爆发性出血者。术后1月视力较术前提高者21眼,占52．50％;视力不变14眼,占35．00％;视力下降5眼,占12．50％。术后33眼眼压控制理想,占82．50％,7眼眼压超过21mmHg,经药物治疗、局部按摩及早期拆除可调整缝线,术后1月内此7眼中有6眼眼压降至正常。结论对持续高眼压状态的青光眼采用前、后房穿刺联合复合式小梁切除术是安全有效的。     

New perspectives on target intraocular pressure

The evidence in support of intraocular pressure (IOP) lowering to reduce risk of glaucoma onset or progression is strong, although the amount and quality of IOP reduction is less well defined. The concept of a target IOP includes a percentage reduction, calculated IOP, or a predetermined IOP figure or range. Yet none of these strategies have been validated. In addition, our understanding of the way IOP influences glaucoma risk is continuously evolving. Examples of this include the data on IOP fluctuation and lamina cribrosa and cerebrospinal fluid pressure differentials. That these variables are not included in target IOP calculation potentially undermines its accuracy and usefulness. We summarize the evidence for target IOP, new developments in our understanding of IOP and glaucoma pathogenesis, as well as emerging strategies for setting targets and assessing response to treatment.     

可调节缝线在持续高眼压状态下原发性闭角型青光眼手术中的应用

目的 研究可调节缝线在原发性闭角型青光眼持续高眼压状态下小梁切除术中应用的临床效果.方法 将眼压控制不良的原发性闭角型青光眼患者随机分为治疗组和对照组,分别行可调节缝线联合小梁切除术和单纯小梁切除术,并进行临床疗效观察.结果 2组术后1个月视力改善无显著性差异;术后2周内眼压控制有显著性差异,治疗组眼压波动相对平稳,术后3个月时2组眼压变化无显著性差异;治疗组术后浅前房、脉络膜脱离、黄斑水肿等并发症明显低于对照组,术后3个月2组滤过泡比较无明显差异.结论 持续性高眼压状态下行可调节缝线联合小梁切除术能更好的控制患者术后眼压,减少术后浅前房、黄斑水肿及脉络膜脱离等并发症的发生.     

Surgical lowering of elevated intraocular pressure in monkeys prevents progression of glaucomatous disease

Recent reports from large clinical trials have clearly demonstrated that lowering intraocular pressure (IOP) in persons with ocular hypertension has a beneficial effect on reducing the progression of glaucomatous disease. Few studies of this effect have been conducted in controlled laboratory settings, however, none have been conducted using non-human primates, the model of experimental glaucoma considered most similar to the human disease. Using data collected retrospectively from a trabeculectomy study using 16 cynomolgous monkeys with experimental ocular hypertension, we evaluated both the threshold of elevated IOP required to cause clinically observable damage to the optic nerve head and also if lowering IOP below this threshold prevents further damage. An index of the level of elevated IOP experienced by experimental eyes (the Pressure Insult) was calculated as the slope of the difference in cumulative IOP between experimental and control eyes during four intervals of time over the course of the experiment, while damage to the optic nerve head was evaluated by measuring the Cup:Disc ratio for each eye from stereoscopic photographs taken at the end of each interval. An increase in the Cup:Disc ratio was significantly associated with both the maximum IOP obtained in the experimental eye during each interval (r=0.573, P<0.001) and the Pressure Insult (r=0.496, P<0.001). Pressure Insult values less than 11 mm Hg Days/Day were not associated with glaucomatous damage in monkey eyes, whereas values greater than 11 showed a significant correlation with increasing Cup:Disc ratios (P<0.001). Trabeculectomy to reduce the Pressure Insult below 11 was correlated with an attenuation of the rate of progression of the Cup:Disc ratio in eyes that had exhibited damage before surgery. These results contribute further to our understanding of this model of experimental glaucoma by demonstrating a threshold at which IOP needs to be elevated to stimulate damage, while also providing corroborating evidence that lowering IOP in ocular hypertensive monkeys can attenuate the progression of glaucomatous disease.     

Impact of intraocular pressure fluctuations on progression of normal tension glaucoma

AIM: To investigate short- and long-term intraocular pressure (IOP) fluctuations and further ocular and demographic parameters as predictors for normal tension glaucoma (NTG) progression. METHODS: This retrospective, longitudinal cohort study included 137 eyes of 75 patients with NTG, defined by glaucomatous optic disc or visual field defect with normal IOP (<21 mm Hg), independently from therapy regimen. IOP fluctuation, mean, and maximum were inspected with a mean follow-up of 38mo [standard deviation (SD) 18mo]. Inclusion criteria were the performance of minimum two 48-hour profiles including perimetry, Heidelberg retina tomograph (HRT) imaging, and optic disc photographs. The impact of IOP parameters, myopia, sex, cup-to-disc-ratio, and visual field results on progression of NTG were analyzed using Cox regression models. A sub-group analysis with results from optical coherence tomography (OCT) was performed. RESULTS: IOP fluctuations, average, and maximum were not risk factors for progression in NTG patients, although maximum IOP at the initial IOP profile was higher in eyes with progression than in eyes without progression (P=0.054). The 46/137 (33.5%) eyes progressed over the follow-up period. Overall progression (at least three progression confirmations) occurred in 28/137 eyes (20.4%). Most progressions were detected by perimetry (36/46). Long-term IOP mean over all pressure profiles was 12.8 mm Hg (SD 1.3 mm Hg); IOP fluctuation was 1.4 mm Hg (SD 0.8 mm Hg). The progression-free five-year rate was 58.2% (SD 6.5%). CONCLUSION: Short- and long-term IOP fluctuations do not result in progression of NTG. As functional changes are most likely to happen, NTG should be monitored with visual field testing more often than with other devices.     

Damping of intraocular pressure fluctuations

Background: There is increasing evidence that relatively rapid spikes in intraocular pressure may contribute to axonal damage in glaucoma. The present study seeks to quantify the ability of a compressible damping element (a simple air bubble) to reduce intraocular pressure fluctuations induced by a known change in intraocular fluid volume. Methods: A mathematical model describing the damping of intraocular pressure increases for a given infusion volume was developed and compared with experimental data obtained from isolated pig eyes. A damping element (100 µL to 2 mL of air) was added to the system, and the effect on the induced intraocular pressure change for a given infusion volume was assessed. Results: The introduction of the damping element reduced the intraocular pressure change in a volume‐dependent manner consistent with the mathematical modelling. The maximum bubble size tested (2 mL) dampened the intraocular pressure change by an average of 63.5 ± 8.7% at a baseline pressure close to 20 mmHg. Close agreement was seen between the mathematical model and the experimental data. Conclusion: Mathematical modelling and experiments in isolated pig eyes demonstrated that the addition of a damping element in the form of a compressible air bubble is capable of significantly reducing induced intraocular pressure spikes.     

高眼压下青光眼的手术治疗

目的探讨高眼压下行青光眼复合式小梁切除术的疗效.方法对33例(33只眼)应用药物不能控制眼压的青光眼患者,采取术中先缓慢降压的方法,进行复合式小梁切除术.结果术后视力提高20只眼,占60.61%,视力不变8只眼,占24.24%;术后眼压控制≤21mmHg21只眼,占66.67%,局部用药可控制者9只眼,占27.27%.结论对药物不能有效控制眼压的青光眼患者,在高眼压下采取必要措施,进行复合式小梁切除术是可行的.     

高眼压下急性闭角型青光眼小梁切除术的临床观察

目的探讨急性闭角型青光眼发作期持续高眼压状态下行小梁切除术的可行性及效果。方法对应用大剂量降眼压药物2~3 d后眼压仍持续在40 mmHg以上的40例(65眼)行小梁切除术;术中均在切除小梁组织前在巩膜瓣根部中央角膜缘处用剃须刀刺开一小切口,缓慢放出房水,眼压降低后再常规完成手术。结果本组术中及术后均未出现暴发性脉络膜上腔出血、恶性青光眼等严重并发症,术后1周视力≥0.1者64眼;视力≥0.3者39眼;眼压≤21 mmHg者52眼;术后3眼出现脉络膜脱离,7眼前房形成延缓,经治疗后逐渐恢复。本组病例手术后大多数保留了较好的视力。结论药物不能控制眼压的急性闭角型青光眼,及时行前房穿刺加小梁切除术手术治疗十分必要,可以避免视功能的进一步损害。     

Intravenous hypertonic saline to reduce intraocular pressure

Purpose: To quantitate the effect of intravenous hypertonic saline (IVHTS) injection on elevated intraocular pressure (IOP). Methods: Nineteen patients (median age, 65 years; range, 41–84 years) with glaucoma and an IOP 30 mmHg or higher were recruited. A bolus of IVHTS (sodium chloride concentration 23.4%) was injected in an antecubital vein over 10–20 seconds. The IOP and systolic and diastolic blood pressure (BP) were measured frequently for 2 hr. The dosage was 0.5 mmol/kg sodium in 11 patients (Group 1) and 1.0 mmol/kg in eight patients (Group 2). Results: In both groups, a median absolute IOP reduction of 7 mmHg was achieved in 5 min. The maximum median reduction was 7 mmHg (range, 4–16) and 9 mmHg (range, 3–14) at 5 and 16 min after IVHTS in Group 1 and 2, respectively, at which point the median IOP had reduced from 38 and 35 mmHg to 31 and 27 mmHg (p < 0.001), respectively. In both groups, the IOP remained 7 mmHg reduced 2 hr after IVHTS. Systolic BP increased a median of 14.5 mmHg at 3 min and was comparable with baseline after 6 min. Conclusion: Intravenous hypertonic saline solution reduces IOP moderately within minutes for up to 2 hr.     

原发性开角型青光眼患者及正常人的眼压日内波动趋势

目的研究原发性开角型青光眼（POAG）、正常眼压性青光眼（NTG）患者及正常人双眼眼压昼夜波动趋势及其眼压峰值出现的规律，比较双眼眼压波动趋势是否一致。设计前瞻性病例系列。研究对象POAG、NTG患者及正常对照各30例。方法用Goldmann压平眼压计测量眼压日曲线，比较双眼的日眼压波动模式及眼压峰值分布。主要指标眼压测量值。结果眼压峰值出现于非办公时段的正常人为右眼6．7％、左眼10．0％；NTG患者为右眼20．0％、左眼23．3％；POAG患者为右眼23．3％、左眼20.0％。结论POAG、NTG患者和正常人有着不同的眼压昼夜波动模式，且双眼的波动趋势不尽相同，不能完全将双眼等同看待；部分观察对象的峰值眼压分布于非办公时段，办公时段多次眼压测量不能完全代替一日眼压监测。（眼科，2007,16：33．36）     

青光眼昼夜眼压波动

病理性高眼压和较大的昼夜眼压波动是青光眼视神经损害进展的重要危险因素.眼压具有波动性,正常人眼压波动的峰值多出现于凌晨,这种波动与体位、眼灌注压、眼轴等有关.正常眼压性青光眼患者眼压波动是视野进展的重要危险因素,且经24小时眼压监测发现大部分眼压是存在异常的,因此需根据其昼夜眼压曲线明确诊断和针对性治疗;原发性开角型青光眼患者昼夜眼压波动规律与正常人相似,眼压高峰多在夜间,但波动范围可能比正常人大,且双眼的波动呈明显的一致性;激光周边虹膜切开术后的慢性闭角型青光眼患者的昼夜眼压波动较大,其眼压波动与基线眼压和房角粘连程度呈正相关.与激光和药物相比,小梁切除术更有利于控制长期和昼夜的眼压波动.抗青光眼药物中前列腺素类药物是控制昼夜眼压波动效果最好的滴眼剂.     

76例急性闭角型青光眼持续高眼压下行抗青光眼手术的临床效果评价

目的 探讨在持续高眼压下行抗青光眼手术的临床疗效.方法 对76例(76只眼)经常规降眼压处理后眼压仍大于40 mmHg的急性闭角型青光眼患者行抗青光眼手术,观察术后视力、眼压及滤过泡等情况.结果 行小梁切除术38只眼,行超声乳化白内障摘除联合房角分离术26只眼,行超声乳化白内障摘除联合小梁切除术12只眼,术后66例视力较术前有明显提高,术后眼压符合完全成功67只眼(78.1％),符合条件成功4只眼(12.5％),平均眼压(15.88±6.32)mmHg,5只眼(9.4％)失败,27只眼滤过泡为功能性滤过泡,5只眼为非功能性滤过泡.结论 对持续高眼压性青光眼行抗青光眼手术,需依据病情采取不同治疗举措,可取得降低眼压,提高视力,保护视功能的效果.     

高眼压状态下行小梁切除术临床观察

目的探讨高眼压状态下小梁切除术的疗效。方法回顾分析近3a来对17例(18眼)在高眼压状态下实施抗青光眼小梁切除术术后情况,确定其手术效果。结果本组手术17例(18眼),17眼均取得良好效果占94.4%,仅1眼术后继发恶性青光眼,手术失败。结论对持续高眼压状态(超过50.62mmHg患者),在用药效果不理想情况下及时行手术治疗,能有效控制病情,避免视功能进一步受损。     

体位与眼压波动

眼压较大波动是造成青光眼视神经损伤的重要因素,而眼压波动受多重因素影响,体位是其中之一.本文通过介绍体位变化时间对眼压的影响、连续体位变化对眼压的影响、不同卧位对眼压的影响、倒立举重等对眼压的影响、正常人与青光眼患者体位变化眼压比较等来阐述体位变化与眼压的关系,从上巩膜静脉压、血压、眼内容物与前房深度、眼灌注压、激素等五个方面解释体位变化如何影响眼压,并阐述了体位影响眼压的意义.     

结膜瓣大小对小梁切除术后滤过泡形态及眼压的影响

目的:探讨以穹隆部为基底的不同大小结膜瓣切口对小梁切除术后滤过泡的形态及眼压的影响。方法:选择施行小梁切除术的患者61例66眼,根据结膜瓣大小不同随机分为两组,A组33眼为大结膜瓣(3个时钟范围),B组33眼为小结膜瓣(2个时钟范围),密切随诊观察术后滤过泡的形态及眼压情况。结果:术后功能性滤过泡形成率A组(91%)>B组(73%);眼压控制率A组(94%)>B组(76%)。结论:采用以穹隆部为基底的大结膜瓣可提高小梁切除术后功能性滤过泡形成率,从而能更好地控制眼压。