Yamazaki Y, Tachibana S, Ohta N, Yada K, Ohama E
Department of Neurosurgery, Kitasato University School of Medicine, Kanagawa, Japan.
Acta Neuropathol. 1995;90(5):425-31. doi: 10.1007/BF00294801.
This report describes an experimental model of chronic tonsillar herniation and its effects on the spinal cord. In ten rats, a small piece of chemically induced mammary cancer was transplanted to the supraoccipital bone. In all cases, the transplanted cancers grew into the posterior fossa, destroying the supraoccipital bone and compressing the cerebellum extradurally. In six of the ten rats, tonsillar herniation was observed at 8-14 weeks after transplantation. Transdural infiltration of the tumor cells was not apparent in any animal. In those rats with tonsillar herniation (n = 6), the spinal cord from the C5 to the T8 segments showed enlargement of the central canal without exception. Histological examination revealed the following changes: stretching and thinning of the ependymal cells; swelling of the astrocytic processes; and extra-cellular edema, predominantly in the dorsal gray matter, but also in the ventral inner portion of the dorsal column. In the control group (n = 4) and those rats without tonsillar herniation (n = 4), such histological changes of the spinal cord were not observed. Although the lesions can not be regarded as representing mature syringomyelia, they most likely constitute an earlier evolutionary stage.
本报告描述了慢性扁桃体疝的实验模型及其对脊髓的影响。在10只大鼠中，将一小块化学诱导的乳腺癌移植到枕骨上方。在所有病例中，移植的癌症生长到后颅窝，破坏枕骨上方并硬膜外压迫小脑。10只大鼠中有6只在移植后8至14周观察到扁桃体疝。在任何动物中均未发现肿瘤细胞的硬膜内浸润。在那些有扁桃体疝的大鼠（n = 6）中，从C5到T8节段的脊髓无一例外均显示中央管扩大。组织学检查发现以下变化：室管膜细胞伸展和变薄；星形细胞突起肿胀；以及细胞外水肿，主要在背侧灰质，但也在背柱腹侧内部。在对照组（n = 4）和那些没有扁桃体疝的大鼠（n = 4）中，未观察到脊髓的此类组织学变化。虽然这些病变不能被视为代表成熟的脊髓空洞症，但它们很可能构成了一个早期的演变阶段。
