深低温保存兔角膜穿透性移植后神经再生形态的观察

MORPHOLOGICAL OBSERVATION OF CORNEAL NERVE REGENERATION AFTER PENETRATING KERATOPLASTY WITH LONGTERM CRYOPRESERVED RABBIT CORNEAS

①目的观察采用深低温保存和新鲜角膜移植术后，移植角膜神经再生情况以及其形态的差异性。②方法采用深低温保存和新鲜兔角膜行同种异体穿透性移植。通过氯化金浸染技术对两种方法保存角膜移植术后１０～２４０ｄ植片内神经再生形态进行形态学观察。③结果术后３０ｄ内，植片内神经溃变，同时宿主角膜实质神经出芽再生。１２０～１８０ｄ，在边缘处再生的神经形成神经纤维“瘤”样结构，并可见髓鞘再生。术后２４０ｄ，多数植片中央有再生的神经分布，但均失去了正常角膜神经分布形态。④结论在光镜下，深低温保存的角膜移植后对角膜神经再生形态无影响；角膜移植术后角膜神经表现为显著地不完全性再生。

Objective To observe the morphological differences and neural regeneration of rabbit corneal after penetrating keratoplasty(PKP) with fresh and longterm cryopreserved rabbit corneas. Methods Both longterm cryopreserved and shortterm moistchamber preserved fresh rabbit corneas were applied in the keratoplasty. Histological gold chlorid impregnation technique was used to demonstrate morphological features of neural regeneration in the grafts 10￣240d after PKP. Results One month after PKP, the graft nerves degenerated and some stromal nerve trunks in host corneal tissue were sprouting. From four to six month regenerative nerves showed neurofibromalike features at the graft margins,regrowth of myelin was found. At the eighth months regenerative nerves grew into the central zones of most grafts, however normal neural structure and architecture in rabbit cornea was not established. Conclusion This study showes that cryopreservation of cornea does not affect neural regeneration morphologically, but the corneal nerve regeneration is insufficient after PKP.