Masuda K
Department of Ophthalmology, The University of Tokyo School of Medicine, Japan.
Nippon Ganka Gakkai Zasshi. 1996 Dec;100(12):923-36.
Among the many factors involved in the development of glaucoma, the elevation of intraocular pressure (IOP) is the most important. The treatment of glaucoma aims to lower IOP in order to maintain visual function. New anti-glaucoma drugs, latanoprost and nipradilol, have been shown to effect a reduction in IOP equal to that achieved with the equivalent dosage of timolol, with no adverse systemic side effects. The mechanism of the reduction of IOP by these drugs mainly involves the increase of uveoscleral outflow. The success rate of filtering surgery for glaucoma has been increased by using antimetabolites such as mitomycin C (MMC) and 5-fluorouracil (5-FU). The use of MMC during surgery has resulted in a better outcome than with 5-FU. Normal tension glaucoma (NTG) cases are reported to constitute more than 60% of total glaucoma cases in Japan. NTG is different from primary open-angle glaucoma not only in IOP but also in the pattern of the visual field defect, cupping and peripapillary atrophy of the optic nerve head (ONH). The first choice of treatment for NTG is using drugs for reducing IOP and, if necessary, argon laser trabeculoplasty. In addition to these treatments a drug for increasing the blood circulation in the brain, brovinecamine fumarate, has shown beneficial effects in the treatment of NTG. NTG patients whose visual field can be shown by static perimetry to be deteriorating are indicated for filtering surgery. The results of filtering surgery for NTG have been confirmed that it is more effective than drugs for maintaining the visual field. We have developed an instrument using the laser speckle phenomenon for determining the microcirculation in the eye, as well as in the ONH, noninvasively, quantitatively, and repetitively. With the same instrument, the effects of anti-glaucomadrugs on ocular circulation, especially in the ONH, can also be determined. Timolol has no effect on the circulation in the ONH, but carteolol and betaxlol increase the circulation significantly. The Ca(+2)-blocker, nilvadipine, increases the circulation in the ONH. These findings indicate that the drugs increasing the ONH circulation many be beneficial for the control of glaucoma.
在青光眼发病涉及的众多因素中，眼压升高最为重要。青光眼治疗旨在降低眼压以维持视功能。新型抗青光眼药物拉坦前列素和尼普地洛已被证明能降低眼压，效果与等量噻吗洛尔相当，且无不良全身副作用。这些药物降低眼压的机制主要涉及葡萄膜巩膜流出增加。使用丝裂霉素C（MMC）和5-氟尿嘧啶（5-FU）等抗代谢药物提高了青光眼滤过手术的成功率。手术中使用MMC的效果优于5-FU。据报道，正常眼压性青光眼（NTG）病例在日本占青光眼病例总数的60%以上。NTG与原发性开角型青光眼的不同之处不仅在于眼压，还在于视野缺损模式、视神经乳头（ONH）的杯盘比和视乳头周围萎缩。NTG的首选治疗方法是使用降低眼压的药物，必要时进行氩激光小梁成形术。除了这些治疗方法外，一种增加脑血液循环的药物富马酸溴长春胺在NTG治疗中已显示出有益效果。视野经静态视野检查显示正在恶化的NTG患者适合进行滤过手术。NTG滤过手术的结果已得到证实，即其在维持视野方面比药物更有效。我们开发了一种利用激光散斑现象的仪器，可无创、定量且重复地测定眼部以及ONH的微循环。使用同一仪器，还可测定抗青光眼药物对眼部循环，尤其是ONH循环的影响。噻吗洛尔对ONH循环无影响，但卡替洛尔和倍他洛尔可显著增加循环。钙通道阻滞剂尼伐地平可增加ONH循环。这些发现表明，增加ONH循环的药物可能对青光眼的控制有益。
