MULTICENTER CRYOTHERAPY FOR RETINOPATHY OF PREMATURITY

据估计，2,100名婴儿将受到疤痕形式的影响， 早产儿视网膜病变（ROP）每年在美国，许多 更多的病例发生在世界其他国家。 1979年 美国婴儿因ROP而失明的人数约为546人， 据信一直在稳步增长。 的外科治疗 视网膜脱离发生在ROP的晚期， 成功 假设缺血性视网膜组织的消融可以最小化 或终止视网膜前血管增生， 糖尿病眼病 报告称，无论是光凝还是冷冻凝固， 周边视网膜有一些好处， 10年来，仍有足够的治疗失败或 怀疑对接受治疗的眼睛造成伤害，需要谨慎接受冷冻治疗 作为有效的治疗。 不幸的是，没有一个积极的报告包含 足够数量的治疗眼，以产生统计学上有效的 信息. 大多数研究是回顾性的，不对患者进行随机分组 他们有相似的ROP程度。 使用的各种分类方案 使研究无法进行比较。 众所周知， 视网膜病变的阶段可以倒退，离开眼睛，没有严重的 只有少数患有ROP的眼睛会失明 在童年时期。 最近制定的ROP国际分类现在允许 协作试验，病例识别一致， 疾病的统一阶段和观察员之间的数据比较， 不同的地点 目前的建议是随机的，前瞻性的， 经巩膜冷冻治疗安全性和有效性的多中心临床试验 视网膜病变患者的外周视网膜 早产（ROP），在延缓急性疾病进展到严重 瘢痕性晶状体后纤维增生（RLF）分级。 所有合格婴儿的数据（出生体重小于1251克，存活 28天）进行前瞻性累积，以进行描述性分析， 确定ROP发展的因素，如位置、范围和 存在或不存在"+"疾病（ROP国际分类） 在预后中发挥作用。 估计有6,000到7,000名婴儿 随后，将所有婴儿确定为冷冻疗法候选人， 疾病进展到ROP的“阈值”（在第5章中定义）严重程度。 在估计的300至400名临界婴儿中， 本研究中随机分配的受试者预计患有影响两种疾病 眼睛对称。 其中一只眼睛将接受冷冻治疗， 另一只眼睛将不接受治疗， 随机 20%不对称影响的阈值婴儿将只有 第一只眼睛达到随机分配给冷冻疗法的阈值，或者 控制 冷冻治疗的有效性将通过比较治疗组与对照组来判断。 对照眼随访3个月和1年。 为此将 通过在照片阅读中心对照片进行蒙片评价。

An estimated 2,100 infants will be affected by the cicatricial form of Retinopathy of Prematurity (ROP) annually in the United States, with many more cases occurring in other countries throughout the world. In 1979, the number of U.S. infants blinded by ROP was approximately 546, and the nubmer is believed to have been increasing steadily. Surgical treatment of the retinal detachments that occur in advanced stages of ROP has not proven successful. It is hypothesized that ablation of ischemic retinal tissue could minimize or terminate the perverted pre-retinal vasoproliferation, as it does in diabetic eye disease. Reports that either photo- or cryo-coagulation of the peripheral retina have some benefit have been appearing for more than 10 years, yet there have been sufficient reports of treatment failure or suspected harm to treated eyes to warrant caution in accepting cryotherapy as valid treatment. Unfortunately, none of the positive reports contain sufficient numbers of treated eyes to produce statistically valid information. Most studies are retrospective and do not randomize patients who have similar degrees of ROP. The various classification schemes used make comparison of studies impossible. It is well known that impressive stages of retinopathy can regress and leave the eye without serious sequellae, and only a small minority of eyes with ROP go on to blindness during childhood. The recently developed International Classification of ROP now permits a collaborative trial, with consistent identification of cases, enrollment of uniform stages of the disease and comparison of data among observers at different locations. The present proposal is for a randomized, prospective multicenter trial of the safety and efficacy of trans-scleral cryotherapy of the peripheral retina in certain patients with retinopathy of prematurity (ROP), in retarding progression of the acute disease to severe grades of cicatricial retrolental fibroplasia (RLF). Data on all eligible infants (birth weight less than 1251 grams, surviving 28 days) will be prospectively accumulated for descriptive analyses to identify factors in the development of ROP, such as location, extent, and presence or absence of "plus" disease (International Classification of ROP) which play a role in prognosis. An estimated 6,000 to 7,000 infants must be followed, to identify as cryotherapy candidates all infants in whom the disease progresses to a "threshold" (defined in chapter 5) severity of ROP. Approximately 80% of the estimated 300 to 400 threshold infants required to be randomized for this study are expected to have disease affecting the two eyes symmetrically. In these, one eye will receive cryotherapy and the other eye will receive no treatment, the treated eye being selected at random. The 20% asymmetrically affected threshold infants will have only the first eye reaching threshold randomly allocated to cryotherapy or control. Efficacy of cryotherapy will be judged by comparison of the treated vs. the control eyes at three months and one year of follow-up. This will be done by masked evaluation of photographs at a Photograph Reading Center.