局部光凝联合复方血栓通治疗对糖尿病视网膜内微血管异常的影响

目的探讨局部光凝联合复方血栓通胶囊治疗糖尿病视网膜病变（DR）视网膜内微血管异常的疗效。方法 60例视网膜内微血管异常的DR患者,随机分为观察组30例（30眼）和对照组30例（30眼）,两组患者均采用原有的降血糖及降血压等内科治疗。观察组采用局部光凝治疗并加用复方血栓通胶囊,对照组采用全视网膜光凝治疗,疗程均为12周。观察两组视力、视网膜病变及黄斑水肿等情况。结果两组在提高视力、改善视网膜病变、消退黄斑水肿方面,差异均有显著性（P〈0.05）。结论应用局部光凝联合复方血栓通胶囊治疗糖尿病视网膜病变视网膜内微血管异常有较好的临床疗效。     

巩膜外垫压联合视网膜激光光凝治疗硅油眼视网膜脱离的临床分析

目的研究巩膜外垫压手术联合视网膜激光光凝对硅油眼视网膜脱离的治疗效果。方法回顾性分析2009年1月一2012年1月,用巩膜外垫压联合视网膜光凝手术治疗36例硅油眼视网膜脱离的视网膜复位效果。结果全部患者均顺利完成巩膜外垫压手术及随后的视网膜激光光凝,行巩膜外放液5只眼,手术中未发生视网膜嵌顿、眼内出血和眼压显著升高等并发症;手术后1周视网膜复位21只眼（58．33％）,剩下15只眼1个月后复位7只眼（19．44％）,视网膜脱离总复位率为28只眼（77．77％）;未复位8只眼（22．23％）,改用玻璃体切割手术方式,视网膜成功复位;6个月后取出硅油,随访6个月视网膜无脱离或者脱离范围增加;手术后眼压≥30mmHg（11mmHg=0．133kPa）3只眼,≥20mmHg7只眼,对症治疗1周后眼压均恢复到正常范围。结论巩膜外垫压联合视网膜激光光凝治疗硅油眼视网膜脱离,手术简单,复位率高,可为硅油眼视网膜脱离首选手术方式,对于巩膜外垫压手术失败和复杂的硅油眼视网膜脱离,应当选择玻璃体切割手术方式。     

Relation between skin surface temperature and minimal blanching during argon,Nd-YAG 532, and CW dye 585 laser therapy of port-wine stains

Laser photocoagulation has proven to be valuable in the treatment of port-wine stains. In this application, the minimal blanching technique is used as an indicator of suitable dosage since it has been demonstrated that the immediate appearance a white mark is required to achieve permanent blanching a few months later. The objective of the investigations undertaken in this study was to correlate the temperature attained at the surface of port-wine stains with immediate blanching, upon irradiation with different laser fluences. A comparative study was performed using an argon laser (all lines), a 532 nm Nd:YAG and a 585 nm argon pumped dye laser. Surface temperature was studied using an infrared camera. Temperature was measured on 10 different port-wine stains using different fluences. Whitening threshold fluence was related to surface temperature. It appeared that whitening threshold fluence corresponded to a surface temperature of 53°C (±3°C). The whitening threshold fluence was dependent on port-wine stains and wavelength. However, whitening threshold fluence remained lower for 532 nm and 585 nm and it correlated to the absorption curve of hemoglobin. © 1993 Wiley-Liss, Inc.     

白内障摘除联合人工晶状体置入术后糖尿病视网膜病变的激光治疗

目的：观察BVI半导体眼科激光治疗糖尿病性白内障患者白内障摘除联合人工晶状体(IOL)置入术后视网膜病变的疗效。方法：采用法国BVI半导体眼科激光治疗仪对46例50只眼的光凝术方法及治疗效果进行回顾性分析。结果：35只眼行广泛视网膜光凝术，15只眼行局部视网膜光凝术，其中6只眼伴有人工晶状体后囊混浊，先期行Nd：YAG激光切开后囊膜。3个月后行荧光素眼底血管造影(FFA)检查，新生血管大部萎缩，视网膜水肿消退。视力稳定无变化36只眼，视力下降14只眼。结论：适时的白内障摘除联合IOL置入，合理及时的激光治疗，是控制糖尿病患者眼底病变继续恶化的重要手段。FFA是进行正确有效激光治疗的重要参考依据，而放置大直径IOL又是完善眼底激光治疗的先决条件。     

532-nanometer green laser beam treatment of superficial varicosities of the lower extremities

Green laser light at 532 nm was utilized in an attempt to thrombose and blanch superficial varicosities of the lower extremity in 14 patients. Selective vascular damage with sparing of overlying skin was the theoretical rationale for use of green light. Seven of the 14 patients achieved satisfactory results (total or near-total obliteration of vessels without scarring) after a 6-month period of observation.     

Senile Macular Degeneration – The Effects and Management

This third paper in the series on the effects and management of senile macular degeneration (SMD), describes the ophthalmic management of early SMD. The roles of fundus examination, fundus photography and fluorescein angiography in the diagnosis of the condition are detailed. Criteria for referral of patients with suspected SMD for ophthalmological investigation and possible treatment are given and the cause and treatment of SMD is discussed.     

Laser balloon angioplasty: effect of exposure duration on shear strength of welded layers of postmortem human aorta

Laser Balloon Angioplasty (LBA) is a technique that may improve the results of balloon angioplasty by thermally sealing arterial dissections and reducing elastic recoil. To define the relationship between laser-exposure duration and the strength of thermal welds made between separated layers of arterial wall, 360 1-cm discs of human postmortem aorta were lased for six different exposure intervals at three different temperature ranges, comparing shear strength of thermal welds in the different groups. Twenty discs were lased to achieve plateau adventitial temperatures of 95 degrees C-104 degrees C (group A), 105 degrees C-114 degrees C (group B), or 115 degrees C-124 degrees C (group C) at each of the exposure periods (5, 10, 15, 20, 25, and 30 sec). A 400-micron fiberoptic coupled to a 1.06 micron continuous wave neodymium:YAG laser was placed perpendicularly 8 mm above the luminal surface of each disc, which had been split midway between the intimal and adventitial surface and reapposed. Mean laser energy ranged 78-378 J delivered in a decremental stepwise fashion to achieve quickly and maintain the target plateau tissue temperature. Mean weld strength increased in relation to both achieved tissue temperature and laser-exposure duration, with at least 10 sec necessary, at temperatures greater than 95 degrees C, for reliable thermal welding. Laser exposure for greater than 20 sec provided no statistical increment in weld strength. In the anticipated clinical performance of LBA, these data suggest that when thermal fusion of disrupted arterial tissues is desired, a laser-exposure duration of 10-20 sec is optimal.     

Comparison of magnetic resonance images and the histopathological findings of lesions induced by interstitial laser photocoagulation in the brain

Interest has developed in using magnetic resonance (MR) imaging to monitor the volume of tissue destroyed by interstitial laser photocoagulation (ILP). In these experiments, ILP was induced in the normal brains of 9 anesthetized cats by delivering 1.5 W of continuous-wave Nd:YAG laser energy (1,064 nm) from a single 400-μm core optical fiber for 1,000 s. The irradiations were monitored using proton spin-echo MR imaging during and immediately after ILP and at postirradiation survival times of 2, 5, and 14 days. At 2 days postirradiation, the necrotic thermal lesion consisted of a central cavity surrounded by 2 concentric zones of coagulative necrosis, one dense and the other dispersed. The lesion shrank and the zonal appearance became less obvious over the 14 day survival period. An enhancing halo on contrast-enhanced T1-weighted images acquired immediately postirradiation best approximated the total lesion diameter at 2 days. These images also indicated that the volume of tissue destroyed during ILP corresponded better to the necrotic volume determined at 2 days than at 5 days and 14 days postirradiation. T2-weighted images acquired during and immediately after ILP consistently underestimated the total lesion diameter at 2 days. © 1993 Wiley-Liss, Inc.     

Laser photocoagulation of prostate: Influence of dosimetry

Background and Objective: Recently, increasing enthusiasm has been shown for application of lasers for the treatment of benign prostate hyperplasia (BPH). However, little is known about the thermodynamics of prostatic tissue response during laser irradiation and how the treatment outcome can be optimized. Our objective was to conduct a systematic study of the influence of exposure parameters on the extent of tissue coagulation and to determine the effects of rate of tissue heating on lesion size by comparing the tissue response to high laser power rapid heating vs. low laser power slow heating. Study Design/Materials and Methods: Nd: YAG laser irradiation of prostate was performed in 15 mongrel canines, using an incident power of 15, 30, or 50 Watts (at the fiber tip) and an exposure time varying from 30 to 300 seconds. The laser beam was delivered via a Urolase side-emitting catheter. The tissue response was compared based on gross as well as histological evaluations of thermal lesions. Results: The depth of coagulation necrosis increased as the laser power was reduced from 50 W to 30 W and further to 15 W while the total delivered energy was kept constant at 2,700 J by adjusting the exposure time. The difference between the three heating rates was more dramatic when the estimated volume of coagulated tissue was considered. Increasing the irradiation tune for the low power (15 W) from 180 to 300 seconds resulted in enlarging the coagulated volume by a factor of 1.6. However, for high power (50 W), increasing the exposure time from 54 to 90 seconds resulted in increasing the coagulated volume by a factor of 1.2. Conclusion: This study suggests that a slow heating regimen yields larger volumes of coagulation necrosis than the currently used rapid heating approach. © 1995 Wiley-Liss, Inc.     

Panrefinal Photocoagulation Influence on Vitrectomy Results for Complications of Diabetic Retinopathy

Despite panretinal photocoagulation (PRP), some diabetic eyes develop complications that are correctable with vitrectomy. The results of vitrectomy performed on 80 eyes having previtrectomy PRP are compared with 402 eyes without photocoagulation. The preoperative findings and operative procedures were almost identical, except the PRP cases had a slightly higher incidence of preoperative iris rubeosis and traction macular detachments, and more surgical membrane peeling. Six months after vitrectomy, the PRP eyes had slightly better visual acuities and fewer detached maculas, but were otherwise almost identical to the non-photocoagulated eyes. There was no evidence that pre-vitrectomy PRP prevents postoperative iris rubeosis.