Koch D D, Kohnen T, Anderson J A, Binder P S, Moore M N, Menefee R F, Valderamma G L, Berry M J
Cullen Eye Institute, Baylor College of Medicine, Department of Ophthalmology, Houston, Tex 77030, USA.
J Refract Surg. 1996 Jul-Aug;12(5):623-34. doi: 10.3928/1081-597X-19960701-16.
Noncontact holmium:YAG laser thermal keratoplasty (Ho:YAG LTK) is a promising new technology for correction of hyperopia and astigmatism. We studied the acute histologic changes and wound healing response following Ho:YAG LTK performed with treatment parameters encompassing those used in clinical studies.
We performed 10-pulse noncontact Ho:YAG LTK on three human corneas 1 day before their removal at penetrating keratoplasty and on six New Zealand white rabbit corneas followed for up to 3 months. Tissues were studied with light and transmission electron microscopy and immunohistochemistry.
The amount of acute tissue injury increased according to the pulse radiant energy. In human corneas, changes in the irradiated zones included epithelial cell injury and death, loss of fine filamentous structure in Bowman's layer, disruption of stromal lamellae, and keratocyte injury and death. In the rabbit corneas, similar acute changes were noted. By 3 weeks, epithelial hyperplasia and stromal contraction were present. Wound healing in the rabbits included repair of the epithelial attachment complex, keratocyte activation, synthesis of type I collagen, partial restoration of stromal keratan sulfate and type VI collagen, and retrocorneal membrane formation.
Noncontact Ho:YAG LTK produces acute epithelial and stromal tissue changes and in rabbit corneas stimulates a brisk wound healing response.
非接触式钬：钇铝石榴石激光热角膜成形术（Ho:YAG LTK）是一种用于矫正远视和散光的有前景的新技术。我们研究了采用涵盖临床研究中使用参数的治疗参数进行Ho:YAG LTK术后的急性组织学变化和伤口愈合反应。
在穿透性角膜移植术前1天，对3个人类角膜进行10次脉冲非接触式Ho:YAG LTK，并对6只新西兰白兔角膜进行该手术，随访长达3个月。通过光镜、透射电子显微镜和免疫组织化学对组织进行研究。
急性组织损伤量随脉冲辐射能量增加而增加。在人类角膜中，照射区域的变化包括上皮细胞损伤和死亡、Bowman层中细丝状结构丧失、基质板层破坏以及角膜细胞损伤和死亡。在兔角膜中也观察到类似的急性变化。到3周时，出现上皮增生和基质收缩。兔角膜的伤口愈合包括上皮附着复合体修复、角膜细胞活化、I型胶原合成、基质硫酸角质素和VI型胶原部分恢复以及后弹力膜形成。
非接触式Ho:YAG LTK可引起急性上皮和基质组织变化，并在兔角膜中刺激活跃的伤口愈合反应。
