EFFICACY OF PRISM ADAPTATION IN ACQUIRED ESOTROPIA

回顾性研究表明，只有50%的手术患者， 后天性内斜视通过一次手术获得良好的眼位对准。 新 有证据表明，术前使用IF棱镜， 一次操作即可实现对准， 后天性内斜视的外科病人。 一项多中心、随机、 前瞻性的临床试验，仔细注意标准化， 提出了无偏的结果评价，以确定：1。整体 通过比较棱镜适配过程的有益效果 对于棱镜适应角进行手术的适应反应者，以及 棱镜适应无反应者，他们接受了原始角度的手术， （B）不具有棱镜适应并且具有 手术矫正原有的偏斜角度; 2.患者是否 对棱镜适应有反应的后天性内斜视， 通过对棱镜适配角或初始角进行操作来校正 偏差：3.对棱镜适应有反应的患者是否 开发新的稳定偏斜角，手术效果更好 与对棱镜适应无反应的患者相比;以及4.是否某些 输入变量有助于预测哪些患者更有可能 从棱镜适应中获益。 为了回答这些问题，一项双随机研究 被设计。 五分之三的患者将被随机选择， 在手术前进行棱镜调整。 五分之二的病人 将根据常规测量的交叉量进行手术 检查技术。 在那些对棱镜有反应的病人中， 一半的人将根据所需的棱镜数量进行手术， 稳定偏斜，其余患者根据 最初测量的交叉点。 如果棱镜适应确实导致更成功的手术， 在实现减少的长期目标方面具有重大影响 后天性内斜视的治疗费用和发病率。 大约2，500例后天性内斜视的再次手术， 年在美国。 如果能减少三分之二， 利用棱镜调整，ezch业务费用在2，000美元之间 和3,000美元（住院费用+医生费用），总节省美元 每年将在320万至480万美元之间。 莫尔蒂会 手术并发症也相应减少 发生，从学校或工作中损失的时间更少， 对病人造成心理创伤

Retrospective stidies indicate that only 50% of surgical patients with acquired esotropia achieve good eye alignment with one surgery. New evidence indicates that with the preoperative use if prisms, good eye alignment can be achieved with one operation in approximately 85% of surgical patients with acquired esotropia. A multicenter, randomized, prospective, clinical trila with careful attention to standardization and unbiased outcome evaluation is proposed to determine: 1. The overall beneficial effect of the prism adaptation procedure by comparing (a) prism adaptation responders who have surgery for the prism adapted angle, and prism adaptation non-responders who have surgery for the original angle of deveation to (b) those patients who do not have prism adaptation and have surgery for the original angle of deviation ; 2. Whether patients with acquired esotropia who respond to prism adaptation are more accurately corrected by operating for the prism adapted angle or the original angle of deviation: 3. Whether patients who respond to prism adaptation by developing a new stable angle of deviation, have a better surgical result than patients who donot respond to prism adaptation; and 4. Whether certain input variables are useful in predicting which patients are more likely to benefit from prism adaptation. In an effort to answer these questions a double randomization study has been designed. Three-fifths of the patients will be randomly selected to go through prism adaptation prior to surgery. Two-fifths of the patients will have surgery based on the amount of crossing measured using routine examination techniques. Of those patients who respond to the prisms, one-half will have surgery based on the amount of prism required to stabilize the deviation while the rest have surgery based on the amount of crossing originakly measured. If prism adaptation does lead to more successful surgery, its adoption can have a significant effect in meeting the long term objective of decreasing the cost and morbidity for the treatment of acquired esotropia. Approximately 2,500 reoperations for acquired esotropia are performed each year in the United States. If these could be reduced by two-thirds through utilization of prism adaptation, with ezch operation costing between $2,00 and $3,000 (hospital cost + physician's fees), the total dollar saving would be between $3.2 million and $4.8 million per year. Morbidity would likewise be reduced, with proportionally fewer operative complications occurring, less time lost from school or work, and considerably less phychological trauma to the patient.