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氩激光治疗中心性浆液性脉络膜视网膜病变   总被引:7,自引:0,他引:7  
应用氩绿激光光凝治疗中心性浆液性脉络膜视网膜病变36例41只眼。结果视力≥1.0者从术前的17.1%增加到术后的63.5%,而视力≤0.6者从术前的61%降低到术后14.6%,术后1周至1月,多数患眼视网膜下液全部吸收,部分患眼中心凹反光重显。结果还显示术后视力与病程长短有关,但术后视力与渗漏点的方位、渗漏点中心凹距离以及神经上皮脱离的大小无关。  相似文献   
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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.  相似文献   
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目的 比较在行氩激光全视网膜光凝治疗中使用不同接触镜填充液对中央角膜厚度的影响 ,以寻找最适用于该治疗的填充液。方法 对 4 6例 (5 2眼 )患者进行氩激光全视网膜光凝治疗 ,每次分别随机使用 0 2 5 %氯霉素、1%羧甲基纤维素及医用透明质酸钠组作为安放全眼底激光角膜接触镜填充液 ,在治疗前及治疗后均用角膜测厚仪测量患者中央角膜厚度。结果 治疗后使用 0 2 5 %氯霉素组中央角膜平均增厚 (31 4± 10 2 ) μm ,1%羧甲基纤维素组中央角膜平均增厚 (10 6± 4 3) μm ,医用透明质酸钠组中央角膜平均增厚 (8 0± 3 5 ) μm。方差分析显示 :氯霉素组与另两组差异有极显著性意义 (P <0 0 1) ,羧甲基纤维素组与透明质酸钠组差异无显著性意义 (P >0 0 5 )。结论  1%羧甲基纤维素及医用透明质酸钠作为安放全眼底激光角膜接触镜的填充液对角膜水肿程度的影响明显小于0 2 5 %氯霉素 ,是可供选用的优良填充液  相似文献   
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We studied retrospectively 12 eyes with a solitary choroidal hemangioma in 12 patients over a period of 13 years. A peculiar, even hyperfluorescence of the tumor within the retinal venous phases occurred in all 12 cases. In all but four patients, laser therapy was performed to reduce subretinal fluid and partially destroy the tumor. Two of the three eyes without extensive retinal detachment or cystoid macular edema at the initial visit regained a final vision of 20/30 or better. The remaining 5 patients with the two major complications had a final vision of 20/80 or worse due to degenerative retinal changes. We believe that laser treatment is definitely advisable in the early stages of a circumscribed choroidal hemangioma.The study was performed at the Institute of Ophthalmology, University of Nijmegen.  相似文献   
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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.  相似文献   
8.
Three-dimensional finite-element models provide a method to study the relationship between human scalp potentials and neural current sources inside the brain. A new formulation of dipole-like current sources is developed here. Finiteelement analyses based on this formulation are carried out for both a threeconcentric-spheres model and a human-head model. Differences in calculated scalp potentials between these two models are studied in the context of the forward and inverse problems in EEG. The effects of the eye orbit structure on surface potential distribution are also studied.  相似文献   
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Many researchers interested in sexual orientation can be separated into two camps: The lumpers, who try to reduce sexual classifications to as small a number of categories as possible, and the splitters, who try to show differences among groups and individuals that make classification schemes increasingly difficult and/or intricate. We report factor analyses of the Klein Grid (a questionnaire with 21 sexual orientation items) to see how many factors emerge in two samples of strikingly different origins. In both samples, the first factor to emerge loaded substantially on all of the Klein Grid's 21 items. This factor accounted for a majority of the variance. In both samples, a second, correlated factor emerged which indexed a separation between most of the items and those having to do with social and/or emotional preferences. In both samples, a third correlated factor also emerged, but this factor differed between the two populations: one refined the social/emotional distinction and the other distinguished ideal behavior from past and current behavior. We conclude on the basis of our analysis that both the lumpers and the splitters are correct.Supported by NIMH grants IP50 MH 45294 and R01 MH 43298.  相似文献   
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为探讨、分析氩激光治疗视网膜阻塞新生血管的疗效。氩激光治疗视网膜静脉塞新生血管55例,中央静脉塞行全视网膜光凝。分支静脉阻塞区域播散性光凝,光斑200-500μm,时间0.1-0.2s,能量0.12-0.4w,Ⅱ级光斑,蓝绿色光波,黄斑格栅光凝光斑100μm,时间0.1s,能量视病情而定,以Ⅰ级反应为度,绿色光波。结果:55例中44例有效,新生儿血管消嫁总有效率80%,无效11例(其中视盘有新生血  相似文献   
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