透明质酸酶在眼科应用的研究进展

透明质酸酶结构复杂,功能特殊,具有多种生物学活性。作为透明质酸的专一性水解酶在医学和生物学领域有广泛的研究和应用。近年来透明质酸酶在眼科手术局部麻醉,白内障及其并发症、青光眼、玻璃体视网膜疾病等方面的基础研究和临床应用报道很多,并有部分涉及甲状腺相关眼病等疾病的治疗应用情况。现将透明质酸酶基本性质及其在眼科应用的进展作一综述。     

透明质酸酶在眼科手术中的应用研究进展

透明质酸酶在眼科临床已广泛使用，但它在球周麻醉中的加用与否还存在争议，在白内障手术中它可以溶解前房内残留的透明质酸，但其在青光眼手术中的作用还不能肯定，在视网膜玻璃体手术中的应用尚停留在动物实验阶段，本就透明质酸酶的作用及其在眼科手术方面的研究和应用进展进行综述。     

透明质酸酶在眼科手术中的应用研究进展

透明质酸酶在眼科临床已广泛使用 ,但它在球周麻醉中的加用与否还存在争议。在白内障手术中它可以溶解前房内残留的透明质酸 ,但其在青光眼手术中的作用还不能肯定 ,在视网膜玻璃体手术中的应用尚停留在动物实验阶段。本文就透明质酸酶的作用机制及其在眼科手术方面的研究和应用进展进行综述。     

纤溶酶和透明质酸酶诱导猪眼玻璃体后脱离

机械性玻璃体切割手术将玻璃体皮质完全从视网膜上分离较困难，且容易引起医源性并发症。在玻璃体手术过程中或手术前能否应用一些生物酶或其他药物使玻璃体液化，并沿着玻璃体视网膜界面分离玻璃体，从而增加手术效率和安全性成为眼科医生期待解决的问题。我们以贵州小型猪为研究对象，观察了纤溶酶和透明质酸酶诱导玻璃体后脱离（PVD）的有效性和安全性，探讨其对玻璃体切割手术的辅助作用。[第一段]     

玻璃体替代物的研究进展

复杂的玻璃体视网膜手术中,常常需要玻璃体替代物支撑玻璃体腔、维持眼内压.气体、膨胀气体、全氟化碳液体、硅油是现代玻璃体视网膜手术中常用的玻璃体替代物,胶原、透明质酸、水凝胶等被尝试用作长期的玻璃体替代物.理想的人工玻璃体一直是研究的热点.本文就目前应用的以及仍处于实验阶段的玻璃体替代物进行综述,根据其功能、构成及特性进行分类,并讨论它们的临床应用及优缺点,同时定义理想人工玻璃体的标准.     

纤溶酶和透明质酸酶在诱导猪玻璃体后脱离中对眼前部组织的安全性研究

目的:研究纤溶酶和透明质酸酶玻璃体内注射诱导猪玻璃体后脱离对眼前部组织的影响,探讨其眼前部组织的安全性.方法:15只健康无眼疾贵州小型香猪,分为A,B,C组,每组5只,每只1眼为实验眼,另1眼为对照眼,实验组与对照组各15眼.实验眼玻璃体内注射酶,A组50U(0.1mL)透明质酸酶,B组0.5U(0.1mL)纤溶酶,C组0.5U(0.05mL)纤溶酶 50U(0.05mL)透明质酸酶,对照眼注射等量BSS液.注射前后分别行裂隙灯显微镜、间接眼底镜、Sch(o)tz眼压计临床检查.7d后摘除眼球,行组织学检查.眼前部组织角膜、虹膜做光镜观察,睫状体、晶状体上皮做透射电镜超微结构的研究.结果:7d后A,B,C组实验眼及各组对照眼无明显眼内炎症反应,术前术后眼压变化差异无统计学意义.实验眼光镜观察角膜、虹膜组织结构无明显异常,电镜观察晶状体、睫状体上皮,细胞形态规则,结构清晰,胞膜完整,周界清楚,连接紧密,对照眼光镜及电镜观察组织结构与实验眼无差异.结论:0.5U纤溶酶和50U透明质酸酶猪玻璃体内注射诱导玻璃体后脱离中安全,无眼前部组织的毒性病理变化.     

组织纤维蛋白溶酶原激活剂联合透明质酸酶致玻璃体后脱离的实验研究

玻璃体后脱离（posterior vitreous detachment，PVD）直接影响玻璃体切割术的操作过程及手术效果，手术前通过非手术方法诱导PVD可缩短手术进程。本文采用组织纤维蛋白溶酶原激活剂（tissue plasminogen activator，t-PA）联合透明质酸酶诱导PVD，探索其在玻璃体切割术中的作用和安全性。     

纤维蛋白溶酶联合透明质酸酶治疗玻璃体积血的实验研究

目的研究纤维蛋白溶酶联合透明质酸酶对玻璃体积血的治疗效果。设计实验性研究。研究对象40只兔（40眼）。方法将40只兔随机分为A、B、C、D组,每组10只,右眼作为实验眼。取自体耳缘静脉血0．1ml注射入玻璃体腔内形成玻璃体积血模型,24小时后A组玻璃体腔内注射纤维蛋白溶酶1u＋透明质酸酶20U（0．1m1）;B组纤维蛋白溶酶1U（0．1m1）;C组透明质酸酶20U（0．1m1）;D组BSS溶液0．1ml。术后7天内行间接检眼镜对眼底各象限透明度观察并分级,各象限分级数值总和为玻璃体积血指数,评价玻璃体积血吸收情况;行B超、扫描电镜检查玻璃体后脱离（PVD）发生情况。主要指标玻璃体积血指数、完全性玻璃体后脱离发生率。结果注射后7天各组玻璃体积血指数中位数及四分位间距分别为：A组4（2～5．25）;B组7（6～8）;C组10（10～11）;D组12（10～12）。各组玻璃体积血指数两两比较A组与B、C、D组的差异均有统计学意义（P均〈0.01）。B超显示各组完全性PVD发生率：A组10例（100％）,B组8例（80％）,C组及D组均未发生。结论1U纤维蛋白溶酶联合20U透明质酸酶玻璃体内联合注射可有效促进玻璃体内积血团块的分解,并可有效地液化玻璃体诱导PVD,加速血液的播散和吸收。     

透明质酸酶诱导玻璃体后脱离的实验研究

目的 研究透明质酸酶诱导玻璃体后脱离的安全性和有效性。方法 选取成年健康纯种新西兰白兔15只，随机分为A、B、C3组。随机选取每只兔的一眼为实验眼，另一眼为对照眼。A组玻璃体腔注入透明质酸酶5IU／0．1mL，B组透明质酸酶10IU／0．1mL，C组透明质酸酶20IU／0．1mL，对照组眼内注入0．1mL BSS。结果 A组术后所有眼均未见玻璃体后脱离；B、C组于术后第5周出现玻璃体后脱离，并且无出血、渗出或视网膜脱离等并发症发生。结论 浓度为10IU／0．1mL和20IU／0．1mL的透明质酸酶玻璃体腔注射后第5周可形成玻璃体后脱离，并且安全有效。     

纤溶酶联合透明质酸酶最佳组合诱导玻璃体后脱离的研究

目的 探讨纤溶酶联合透明质酸酶诱导大鼠玻璃体后脱离(posterior vitreous detachment,PVD)的有效性和安全性,确定纤溶酶和透明质酸酶联合应用的最佳浓度,为下一步进行药物玻璃体溶解术后白内障动物模型的药物剂量选择提供依据.方法 健康SD大鼠18只随机分为A、B、c 3组,每组6只,右眼均为实验眼,左眼为对照眼.A组实验眼玻璃体内注射纤溶酶0.15 U+透明质酸酶5 U,B组注射纤溶酶0.25 U+透明质酸酶5 U,C组注射纤溶酶0.50 U+透明质酸酶5 U,左眼玻璃体内均注射眼用平衡盐液10 μL.注药前后常规行裂隙灯、直接眼底镜检查观察眼部一般情况,7 d后处死动物并摘取眼球标本做扫描电子显微镜检查和组织病理切片检查,观察玻璃体视网膜内界膜和视网膜组织结构的情况.结果 各组实验眼裂隙灯检查均未发现明显眼内炎症反应.扫描电子显微镜结果显示,各组实验眼均有不同程度PVD的发生,其中A组出现部分性PVD占5/6,完全性PVD占1/6;B组出现部分性PVD占1/3,完全性PVD占2/3;C组均出现完全性PVD,发生率为100%;对照眼均未见PVD发生.A、B、C 3组实验眼出现完全性PVD的总发生率为61.1%(11/18),与3组对照眼(0/18)相比,差异有显著统计学意义(P<0.001).C组实验眼出现完全性PVD的发生率为100%(6/6)与A组实验眼16.67%(1/6)比较,差异也有统计学意义(P=0.015).光学显微镜检查各组注射眼均未发现视网膜组织结构的异常改变.结论 玻璃体内联合注射0.50 U纤溶酶和5 U透明质酸酶诱导玻璃体液化和完全性PVD发生的效果最好,对眼内组织无明显的毒性作用.     

Enzyme-assisted vitrectomy in enucleated pig eyes: a comparison of hyaluronidase, chondroitinase, and plasmin

PURPOSE: Facilitation of vitrectomy by vitreolytic enzymes may be of great value in complicated or office-procedure vitreo-retinal surgery. In this study, we quantified and compared the effect of hyaluronidase, chondroitinase, and plasmin pre-incubation on vitrectomy rate and explored potential retinal damage. METHODS: Freshly enucleated pigs eyes were incubated (1 or 3 hours) with an intravitreally injected enzyme or control solution. Enzyme doses were 100 and 1000 U for hyaluronidase, 1 and 2 U for chondroitinase, 3 and 30 U for plasmin. The eyes were weighed before and after 10 minutes of one-port vitrectomy, the difference representing the amount of removed vitreous. Light microscopy was used to assess potential damage to the retina. RESULTS: All enzymes significantly increased the amount of removed vitreous at all doses and incubation periods. The highest increase was found with hyaluronidase 1000 U, 3 hours, the lowest with chondroitinase 1 U, 1 hour. Damage occasionally occurred to the internal limiting membrane and very rarely to the nerve fiber layer. No damage at all was seen in the 100 and 1000 U hyaluronidase (1-hour incubation) groups. CONCLUSIONS: Hyaluronidase, chondroitinase, and plasmin are good candidates for enzyme-assisted vitrectomy. Although retinal structural damage was very rarely seen, safety concerns will have to be investigated further.     

球后阻滞麻醉中透明质酸酶对眼内压及间接眶压的影响

目的：研究球后阻滞麻醉中使用透明质酸酶对眼内压及间接眶压的影响。方法：采用双盲法，将40例40只白内障术眼随机分成两组：一组用添加150U透明质酸酶的麻药作球后阻滞麻醉，另一组则用添加生理盐水的麻药。分别测量麻醉前、麻醉后即刻、麻醉后5、10、15、20和30分钟的眼内压及间接眶压值，做对比分析。结果：球后阻滞麻醉后两组术眼的眼内压及间接眶压均较麻醉前升高，其中透明质酸酶组眼内压及间接眶压的升高幅度和持续时间均低于生理盐水组。结论：在球后阻滞麻醉中使用透明质酸酶可以降低眼内压及间接眶压的升高幅度和持续时间，增加手术安全性。     

Presence of lysosomal hyaluronidase in human corneoscleral tissue

Hyaluronidase activity in human corneoscleral tissues was biochemically studied. The corneoscleral junction, particularly the inner layer, showed higher activity than other corneoscleral tissues. The possible role of lysosomal hyaluronidase in the trabecular meshwork is discussed.

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Zusammenfassung Biochemische Untersuchung der Hyaluronidaseaktivität in menschlichem Hornhaut- und Skleragewebe. Besonders die inneren Schichten des corneoskleralen Grenzbezirkes zeigten die höchste Enzymaktivität. Diskussion der möglichen Rolle der Hyaluronidase im Trabekelwerk.

     

Diplopia and ptosis following injection of local anesthesia without hyaluronidase.

In a university ophthalmology department, a cluster of postoperative diplopia and ptosis cases occurred in the initial 3 months after hyaluronidase (Wydase) became unavailable for use with injection anesthesia. These cases suggest that hyaluronidase, when used with injection anesthesia, may protect extraocular muscles and nerves from the toxic effects of local anesthetic agents. The spreading action of hyaluronidase facilitates uniform diffusion of anesthetic agents. This prevents elevated extracellular tissue pressure, a cause of ischemic damage to extraocular muscles or nerves. Hyaluronidase may also prevent focal accumulations and concentrations of local anesthetic agents, which at high enough levels may cause myotoxic or neurotoxic damage, fibrosis, and contracture of extraocular muscles or nerves.     

Effect of brimonidine on rabbit trabecular meshwork hyaluronidase activity

PURPOSE: To study the presence of hyaluronidase activity in the rabbit trabecular meshwork and its regulation by brimonidine. METHODS: A spectrophotometric assay that consists of the assessment of N-acetylhexosamine groups released from hyaluronic acid was used to examine hyaluronidase activity. Cyclic adenosine monophosphate (cAMP) levels were assessed by radioimmunoassay. RESULTS: Hyaluronidase activity was detected in the rabbit trabecular meshwork. Its optimal activity was in the acid range of pH 3.8. Brimonidine significantly increased trabecular hyaluronidase-specific activity and decreased cAMP accumulation. Yohimbine significantly inhibited the effect of brimonidine on both hyaluronidase activity and cAMP accumulation. CONCLUSIONS: The finding of endogenous hyaluronidase activity in rabbit trabecular meshwork supports the hypothesis that this tissue can metabolize its own glycosaminoglycan (GAG) products. The present results suggest, however, that the hypotensive effect of brimonidine could be mediated, at least in part, by its ability to increase GAG catabolism, probably through a cAMP-independent mechanism.     

玻璃酸酶在小梁切除术后眼压再升高的应用

目的 玻璃酸酶试用在抗青光眼术后,外引流滤过道粘连阻塞,眼压再升高的治疗作用。方法 分别对18眼小梁切除术后,滤过道粘连阻塞患者,结膜下注射玻璃酸酶,观察疗效及并发症。结果 观察术后6—12月,眼压均在2.79kPa(1kPa=7.5mmHg)以下。结论 玻璃酸酶能明显抑制滤过区组织粘连瘢痕形成,弥补了部分小梁切除术后外引流滤过道粘连阻塞,抗青光眼术后眼压再次升高的不足。另外玻璃酸酶结膜下注射并发症少,无痛苦。     

Hyaluronidase treatment, collagen fibril packing, and normal transparency in rabbit corneas

PURPOSE: Hyaluronidase treatment is the initial step of corneaplasty, a treatment under development that induces stromal softening and involves the application of a custom designed forming lens to achieve modification of refractive error. The purpose of this investigation was to examine changes in the arrangement of stromal collagen fibrils after hyaluronidase treatment. METHODS: Rabbit corneas were evaluated by slit-lamp microscopy at 0, 2 and 7 days after treatment and haze was assessed by subjective observation. Molecular and interfibrillar Bragg spacing of corneal collagen were measured from synchrotron x-ray scattering patterns. Transmission electron microscopy and digital image analysis were used to calculate radial distribution functions from the positions of collagen fibrils. The calculated fibril sizes and positions were also used to predict the transmission of visible light through these corneas. RESULTS: Hyaluronidase-treated corneas were shown to have a decreased interfibrillar Bragg spacing of 15% to 21%. Fibril hydration did not change. Transparency of these corneas remained unaltered. CONCLUSIONS: Hyaluronidase reduced the hydration of the corneal stroma, which led to a more compacted collagen fibril arrangement. This compression was predicted to cause a small reduction in the transmission of visible light through the cornea but not to a point likely to cause visual impairment.     

Intravitreal injection of hyaluronidase cannot induce posterior vitreous detachment in the rabbit

PURPOSE: To investigate whether intravitreal injection of hyaluronidase can induce posterior vitreous detachment (PVD) in the rabbit. METHODS: One eye each of 12 New Zealand white rabbits received intravitreal injection via the pars plana of 20 IU of hyaluronidase (0.1 mL reconstituted in sterile balanced salt solution [BSS]) into the midvitreous cavity. The fellow eye of each rabbit received a vitreous injection of 0.1 mL of BSS. At 3 and 6 months after intravitreal injection, four and eight rabbits were killed, respectively, and the eyes were enucleated. After fixation, scanning electron microscopy was performed to study the vitreoretinal interface. RESULTS: At 3 and 6 months after injection, scanning electron microscopy showed that the retinal surfaces in eyes that received either hyaluronidase or BSS were covered with vitreous collagen fibers. No eyes, even those that received hyaluronidase over a period of 6 months, had the smooth retinal surface consistent with a bare internal limiting lamina that suggests the development of PVD. CONCLUSION: Hyaluronidase cannot induce PVD in the rabbit over a 6-month period after vitreous injection.     

Does the addition of hyaluronidase improve the quality of peribulbar anesthesia in cataract surgery? – A randomized double blinded study

Purpose

To determine the necessity of hyaluronidase as an anesthetic adjuvant for peribulbar anesthesia during cataract surgery and to assess differences in anesthetic outcomes in the absence of hyaluronidase.