即角膜与巩膜移行区，宽约1.5－2.0毫米，由于透明的角膜嵌入不透明的巩膜内，并逐渐过渡到巩膜，所以在眼球表面没有一条明确的分界线。
与传统角巩膜缘切口比较，术中眼压维持稳定，术后手术性角膜散光度数小。
Tunnel incision can make the surgery process easier and induce corneal astigmatism smaller.
目的：观察家兔角巩膜缘局部应用5 -氟尿嘧啶(5 - FU)的治疗效果。
AIM: to observe the effects of topical application of 5-fluorouracil (5-fu) on the rabbits corneal limbus.
结果：交感性眼炎多发生于青壮年，致伤原因多为眼球穿孔伤，受伤部位为角巩膜缘者最多，潜伏期在2 ~ 8周最多。
Results: Sympathetic ophthalmia occurred mostly in younger persons, and the most common causes were ocular perforating injuries, especially at the corneoscleral limbus.
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