Trans-scleral application of a semiconductor diode laser

We used a diode laser with an output power of 1 W through a fiberoptic light pipe (200 microns diameter) to deliver laser energy through the sclera of pigmented rabbits. Ciliary body destruction occurred with energy levels of 300-400 mW and exposure time of 0.5 sec. Retinal photocoagulation was achieved with energy levels of 200-500 mW in 0.5 sec. Histologic examination of acute lesions demonstrated thermal destruction of ciliary body processes and retina. Chorioretinal scar formation was observed clinically and histologically within 2-3 weeks. Our data indicate that the transscleral diode laser may be used for destruction of the ciliary body processes or peripheral retinal coagulation in pigmented eyes.     

Alteration of pulse configuration affects the pain response during diode laser photocoagulation

Background and Objective: The shape of the treatment pulse of the diode laser (810 nm) can be easily altered electronically in contrast to ion laser photocoagulators. We investigated whether changes in laser pulse shape influenced the subjective pain response in patients undergoing retinal photocoagulation when only topical anesthesia was used. Study Design/Materials and Methods: Twenty consecutive patients required peripheral retinal photocoagulation for proliferative diabetic retinopathy or extensive retinal breaks. Three diode pulse waveforms including a square wave, shaped-wave, and an envelope of micropulses were compared to one another. Power was adjusted so that each waveform delivered the same total energy. The patients subjectively ranked the intensity of any pain they experienced for each group of lesions. Responses were compared to one another using an analysis of variance. Results: 40% of patients found the standard square wave pulse to be significantly more painful (P < 0.05) than the shaped pulse mode and 30% found the square wave significantly more painful (P < 0.05) than the micropulse mode. Conclusion: Modification of the laser pulse waveform may ameliorate pain induced by diode laser photocoagulation of the retinal periphery. © 1995 Wiley-Liss, Inc.     

半导体激光体外照射血管治疗仪的研制

为克服 He-Ne激光血管内照射疗法所具有的不足,我们采用830nm、500mW半导体激光器,研制了用于体外血管照射的激光治疗仪.设计了易于固定的激光输出头,并且采用单片机控制整机,提高了仪器的稳定性和可靠性.临床应用取得了令人满意的治疗效果.     

A small-animal activity-analysing system for behavioural studies

Automated recording and data analysis of the activity of small laboratory animals are often required for psychological and other forms of behavioural investigation. This paper describes such a system using an open field of 1·14×1·14 m. Three arrays of infrared-light-emitting diodes and phototransistors are used to locate the animal. Two of the arrays are used to generate an xy grid, while the third one is used to determine whether the animal is rearing. The position of the animal gives rise to both digital and analogue signals; so the equipment can be interfaced directly with a minicomputer, or coupled to an analogue recorder. Several activity parameters, such as the path length (absolute value of the line integral), the time spent at a predetermined area of the open field or the latency to move, are computed and displayed in digital form.     

X(γ)刀输出吸收剂量的测量与验证

目的：目前，国内X（γ）刀的国家检定规程正在起草之中，本文的目的是为X（γ）刀剂量测量提供合理的设备与吸收剂量计算方法。材料与方法：利用德国PTW-UNIDOS剂量仅与有效体积为0．015cc的针尖电离室及自制的小体积半导体探测器相匹配，在160mm直径的有机玻璃球形模体内测量X（γ）刀的输出吸收剂量，并验证其治疗计划的实际输出剂量，得到较满意的结果。结论：为了保证剂量的准确度，X（γ）刀治疗计划系统的实际输出剂量应定期在现场测量与验证，所用探测器的直径应小于射野直径的1／2，小灵敏体积的半导体探测器适宜X（γ）刀小野(如：Ф4mm)的测量。     

三种波长的激光小梁成形术临床疗效比较

目的　对氩激光、倍频Nd：YAG激光、半导体激光小梁成形术的疗效作一前瞻性的评价和比较。方法　随机地将原发性开角型青光眼病人50例84眼分为三个激光组,分别用氩激光、倍频Nd：YAG激光、半导体激光进行小梁成形术,随访三组的有效率。结果　三组各随访期的眼压下降有统计学意义。三组之间的眼压下降数和成功率无差别。结论　三种波长激光都能有效地进行小梁成形术。     

半导体红外激光光凝治疗视网膜静脉阻塞

为探讨半导体红外激光对视网膜静脉阻塞（ＲＶＯ）的治疗效果,对５８例ＲＶＯ患者用Ｋｅｅｌｅｒ公司“Ｍｉｃｒｏｌａｓｅ”半导体激光器（波长８１０ｎｍ）作区域封闭或全视网膜光凝（ＰＲＰ）。结果：１７例中央视网膜静脉阻塞（ＣＲＶＯ）患者,治疗前后平均视力分别为０．１７５及０．４０;７例半球阻塞（Ｓｅｍｉ－ＣＲＶＯ）患者治疗前后平均视力为０．１１６及０．４０;３４例视网膜分枝静脉阻塞（ＢＲＶＯ）患者则分别为０．１９及０．４６５。经ｔ检验,差别均有显著性。结论：激光光凝治疗是ＲＶＯ重建供氧平衡的重要手段,疗效肯定。半导体红外激光有比氩激光更易穿透浑浊介质和更少影响视网膜神经纤维层和黄斑功能等优点。早期进行区域封闭或全视网膜光凝,有利于保存有用视力。     

Semiconductor diode laser transscleral cyclophotocoagulation versus filtering surgery with Mitomycin-C

Both filtering surgery with Mitomycin-C and diode laser cyclophotocoagulation have proved to be effective alternatives in cases of glaucoma with poor surgical prognosis. The right eyes of 40 pigmented rabbits were randomly divided into 2 groups: Mitomycin-C group underwent filtering surgery with application of 0.4 mg/ml of Mitomycin-C whereas the diode laser (DL) group received 15 applications of 1.8 J (1800 mW. 1000 ms) distributed in 270°. Mean IOP showed statistical differences in two periods between days 3–13 and 45–60 — Mann-Whitney U test — with a higher IOP lowering in the DL group. The comparison of IOP survival curves (Log-Rank test) was not significant p = 0.070809. Ocular hypertension, hyphema and inflammatory signs were higher in the DL group, both in short and long term, but in terms of statistical significance only ocular hypertension showed differences p = 0.00011717 - Fisher exact test. Microscopic examination revealed patent sclerostomies in 60% of the MMC group eyes with different grades of fibroblastic proliferation. In the DL group we observed necrosis of the sclieral stroma and of the pigmented and unpigmented ciliary epithelium, with signs of thermal coagulation of the ciliary stroma and of the stromal vasculature. We must point out that the treatment with laser has proved to be more effective although both treatments showed very acceptable IOP lowering until 2 months after the surgery.     

难治性青光眼半导体激光经巩膜睫状体光凝术

目的　评价半导体激光经巩膜睫状体光凝术治疗难治性青光眼的效果和安全性。方法　 68例 (69眼 )接受治疗 ,术后随访 6～ 17月。分析末次治疗后第 6月的眼压、视力和眼部症状。结果　无光感组 (3 6眼 ) :光凝术前眼压 (61.16± 12 .44 )mmHg(1mmHg =0 .13 3kPa) ,末次光凝术后第 6月后 3 3眼眼压 (2 9.67± 6.79)mmHg。 3眼眼球萎缩 ,12眼需 2次或多次治疗。光感及光感以上组 (3 3眼 ) :光凝术前眼压 (5 1.72± 13 .85 )mmHg ,末次光凝术后第 6月眼压 (2 1.42± 8.2 2 )mmHg。其中 11眼需要 2次或 3次光凝术 ,4眼 3次光凝术后眼压仍高于 2 1mmHg。结论　半导体激光经巩膜睫状体光凝术是一种简单、安全、有效的治疗难治性青光眼的方法 ,但常需要重复治疗。     

CCD二极管阵列检测-流动注射分析尿中的肌酐

目的：研究流动注射-CCD二极管阵列检测分光光度法测定尿中肌酐含量的方法。方法：基于经典的Jaffe反应，肌酐能与碱性苦味酸生成橙红色复合物，利用化学动力学反应，采用CCD二极管阵列检测装置快速测定尿中肌酐的含量。本实验探讨了最佳反应条件和流动注射分析参数。结果：本方法的线性范围为1μg／ml～33μg／ml，检出限为1μg／ml。样品的加标回收率在81．63％～119．7％之间，精密度为2．74％～3．96％。将本方法与临床自动生化仪的测定结果比较，经t检验（t=0．179，P〉0．05），两种方法测定结果无统计学差异。结论：本方法采样频率为20次／11，简便快速、分析成本低，实现了尿中肌酐含量的批样分析，获得了满意的结果。