Demarcation laser therapy in the management of macular-sparing persistent subretinal fluid after scleral buckling procedures

Background Persistent or recurrent macular-sparing subretinal fluid (SRF) can sometimes occur following scleral buckling procedures. Observation and reoperation have been used in the management of such cases. Demarcation laser therapy (DLT) has been used to treat macular-sparing retinal detachments in the context of cytomegalovirus retinitis and as primary treatment for selected rhegmatogenous retinal detachments. There are, however, scarce data in the literature regarding its use following primary scleral buckling procedures. The current study explores the use of DLT under the latter circumstances.Methods The medical records of all consecutive patients with persistent SRF sparing the macula following primary rhegmatogenous retinal detachment repair using a scleral buckling procedure were retrospectively reviewed. Only those patients in whom the breaks were localised to the area of indentation and, thus, seemed to be well supported by the buckle were included. Demographics, clinical characteristics of the retinal detachment prior to scleral buckling, extension of the residual SRF observed postoperatively, details of the laser procedure, anatomical and functional outcomes and complications were evaluated.Results Seven patients, all females, with a mean age of 47.9 years (range: 20–81) were included in the study. The retinal detachments were superior (n=3), inferior (n=3) and subtotal, affecting both superior and inferior retina (n=1). Scleral buckling procedures were used to treat the retinal detachments in all cases. Following demarcation laser therapy, the area of SRF remained stable in two patients, and flattened in four. In one patient, extension of SRF occurred requiring further surgery.Conclusions Demarcation laser therapy appears to be a reasonable option in the management of patients with persistent or recurrent SRF sparing the macula following scleral buckling surgery.The authors do not have any proprietary interests in the products or methods utilised in this study     

卵磷脂络合碘合并视网膜光凝治疗糖尿病视网膜病变的临床疗效观察

目的:观察卵磷脂络合碘对糖尿病视网膜病变引起的玻璃体积血、混浊的治疗效果.方法:本研究选用的病例为2005年1～8月到中南大学湘雅二医院门诊就诊的37名(51眼)糖尿病视网膜病变的患者,使用卵磷脂络合碘(1.5mg/)片)的片剂,3次/日,2片/次,对病情严重者行令视网膜光凝配合药物进行治疗.服用时间最长3个月,最短2周.观察时间为2周～3个月.结果:治疗2周后视力提高2行及其以上者5眼,占9.8%(5/51);1月后玻璃体积血明显减少或眼底能见度明显提高数,并能行荧光素眼底血管造影(FFA)检查以及激光治疗的有27眼,占52 9%(27/51):2月后玻璃体积血明显减少或眼底能见度明显提高并能行FFA检查以及激光治疗的达到42眼,占82.3 %(42/51);51眼内玻璃体混浊等级下降1级以上45暇,总有效率为88.2%(45/51),无明显效果有6眼,占11.8%(6/51).结论:卵磷脂络合碘是一种有敛的治疗由糖尿病视网膜病变引起玻璃体积血、混浊的约物. 后视力提高2行及其以上者5眼,占9.8%(5/51);1月后玻璃体积血明显减少或眼底能见度明显提高数,并能行荧光素眼底血管造影(FFA)检查以及激光治 的有27眼,占52 9%(27/51):2月后玻璃体积血明显减少或眼底能见度明显提高并能行FFA检查以及激光治疗的达到42眼,占82.3 %(42/51);51眼内玻璃体混浊等级下降1级以上45暇,总有效率为88.2%(45/51),无明显效果有6眼,占11.8%(6/51).结论:卵磷脂络台碘是一种有敛的治疗由糖尿病视网膜病变引起玻璃体积血、混浊的约物. 后视力提高2行及其以上者5眼,占9.8%(5/51);1月后玻璃体积血明显减少或眼底能见     

The role of clinical drug trial methodology with respect to studies of new drugs. Clinical trials of timolol

The use of the Randomized Clinical Trial (RCT) to assess the safety and efficacy of a new drug or treatment can provide a clear evaluation of the relative benefits and risks of the new therapy as compared to the longer-established treatment methodology. In some cases, such as insulin, the benefits are immediately apparent; in other cases, such as photocoagulation for proliferative diabetic retinopathy, the consensus is not so easily obtained, and the clinical trial can supply the answer. Furthermore, the RCT provides the opportunity to identify adverse reactions, in particular those which present with a seemingly unrelated or unexpected set of symptoms. In conducting clinical trials of timolol, researchers must be alert for beta-adrenergic antagonist effects, such as were seen with practolol, and should be especially careful to note early, mild reactions which may be the forerunners of later, more severe or irreversible adverse effects.     

Laser-induced thermal injury to dermal blood vessels: analysis of wavelength (585 nm vs. 595 nm), cryogen spray cooling, and wound healing effects

BACKGROUND AND OBJECTIVES: Successful laser treatment of cutaneous hyper-vascular lesions requires appropriate laser irradiation parameters for selective photothermolysis of ectatic dermal blood vessels as well as appropriate cooling parameters for epidermal protection based on an individual patient basis. Using the rabbit ear as an in vivo model for dermal vasculature, we investigated the influences of laser wavelength (585 nm vs. 595 nm) and cryogen spray cooling with various spurt durations on the laser-induced thermal injury to dermal blood vessels. Wound healing response was also evaluated in 2 hours and 4 days. STUDY DESIGN/MATERIALS AND METHODS: Flashlamp-pumped pulsed dye laser ScleroPlus (operated at the wavelength of 585 or 595 nm) was used for the comparison between the influences of two wavelengths (585 nm vs. 595 nm). R134-a cryogen spurts with the durations from 50 to 300 milliseconds were sprayed onto the sites to be irradiated and terminated 20 milliseconds before the onset of the laser pulses. In vivo rabbit ear was used as the model for cutaneous hyper-vascular lesions. Totally 10 New Zealand Albino white rabbits were experimented and in each rabbit ear six to seven sites were irradiated. Five animals were sacrificed 2 hours after the irradiation, and the remaining five sacrificed 4 days after the irradiation. Thermal injury to the blood vessel was assessed by hematoxylin and eosin stained histological sections and confirmed by an apoptosis assay. RESULTS: When the radiant exposures were above 10 J/cm2, 595 nm wavelength induced equivalent or more severe thermal injury to dermal blood vessels than 585 nm. Cryogen spray cooling with the spurt durations above 100 milliseconds resulted in increased depth of the most superficial thermal injury to dermal blood vessels than without cooling, indicating that superficial blood vessels were non-specifically cooled by the cryogen spurts applied at these parameters. Laser-induced thermal injury was significantly healed in the rabbit ear vasculature at 4 days post irradiation. CONCLUSIONS: Given sufficient radiant exposure, 595 nm wavelength can induce equivalent or more severe vascular injury compared with 585 nm. Cryogen spray cooling with the spurt durations above 100 ms may impair the photocoagulation of superficial blood vessels. Irreversible thermal injury to blood vessel can be achieved only when the basement membrane of blood vessel wall is irreversibly damaged.     

Argon laser intraocular photocoagulation

Argon laser intraocular photocoagulation is now available during vitreous surgery, to treat retinal breaks and to give panretinal photocoagulation. Twenty patients, including phakic patients with gas-filled eyes, were treated using a new operative contact lens without complication. This intraoperative technique allows controlled rapid application of laser lesions at a safe distance from the retina, and eliminated the need for attempting treatment through the often hazy media of an irritated postoperative eye. A group of five rhesus monkeys were treated with various power settings to assess the histopathologic features of these laser lesions.     

Diabetic retinopathy — Need and demand for photocoagulation and its cost-effectiveness: Evaluation based on services in the United Kingdom

Summary Photocoagulation services in the two Regions, north of the River Thames, treated 6,589 cases of diabetic retinopathy (including an annual incidence of 309 cases) or 20% of the estimated total need for photocoagulation. Sixty-one percent of diabetic retinopathy patients have disease in both eyes. It is cheaper to treat a patient with diabetic retinopathy than to look after a blind person for one year. Hence, adequate training in the identification and early treatment of diabetic retinopathy requiring photocoagulation is urgent.     

Status of hyperthermia in the treatment of advanced liver cancer

The vast majority of patients with malignant liver tumors have inoperable disease. These patients must rely on chemotherapy, radiotherapy, and various locoregional treatments. Although these treatments have demonstrated encouraging response rates, symptom palliation and occasional down staging of tumors, their impact on survival is minor. As a result there has been renewed interest in hyperthermia as a treatment option. This study reviews the current modalities of hyperthermia in terms of clinical results, side effects, limitations, and therapeutic standing.     

激光光凝治疗糖尿病性视网膜病变疗效分析

目的:探讨激光光凝治疗糖尿病性视网膜病变的治疗效果。方法:对我院近3a 176例320眼的糖尿病性视网膜病变,经行激光光凝治疗后,定期观察视力,眼底及眼底荧光造影检查(3 ～4mo),记录新生血管、视网膜出血渗出、玻璃体积血等情况,观察期4mo～3a。结果:完成激光治疗后1mo,视力提高≥2行139眼(43.4)%,无变化123眼(38.4)%,视力下降≤2行58眼(28.1)%。造影示新生血管消退307眼(95.9%),3眼新生血管性青光眼,虹膜新生血管消退,眼压正常。28眼(8.8%)发生玻璃体积血,后行玻璃体切割,术中补激光。结论:激光光凝是治疗糖尿病性视网膜病变的有效方法。     

光学相干断层扫描对氩激光治疗糖尿病性黄斑水肿的疗效观察

目的应用光学相干断层扫描观察氩激光治疗糖尿病性黄斑水肿的临床疗效。方法对糖尿病性黄斑水肿患者行氩激光光凝术。在光凝前、光凝后3个月分别进行扫描获取光学相干断层扫描图像,记录黄斑中心凹视网膜厚度,作统计学分析。结果平均随访(3.0±0.6)个月。光凝前及光凝后3个月黄斑中心凹区视网膜厚度平均值分别为(397±102)μm和(204±90)μm,差异有统计学意义。结论光学相干断层扫描检测能较准确定量测算黄斑区视网膜厚度,可对比观察氩激光光凝前后视网膜厚度变化,进而判断氩激光光凝的疗效。     

早期全视网膜光凝治疗缺血型视网膜中央静脉阻塞

目的　评价早期预防性全视网膜光凝治疗缺血型视网膜静脉阻塞的有效性和安全性。方法　用氩离子激光器 ,对病史短于 3个月的缺血型视网膜静脉阻塞 2 1例 2 1眼 ,行全视网膜光凝 ,10 0 0～ 2 0 0 0个光凝点 (平均15 0 7点 )分 3～ 5次完成。观察光凝前后眼部新生血管的消退和视力变化情况 ,以及远期并发症的发生情况。结果　随访 3个月至 2年 ,平均 18 4个月。无一例发生虹膜新生血管和新生血管性青光眼 ;发生玻璃体出血 2例 ;治疗后视力与治疗前比较差异无显著意义 (P >0 0 5 )。结论　早期全视网膜光凝预防和减少由缺血型视网膜静脉阻塞引起的并发症是有效的 ,能为部分患者赢得治疗时间