Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.

Though several pathogenetic theories concerning the frequent association of Chiari malformation and hydrocephalus with myeloschisis have been suggested, none of them explains all the aspects of the disorder. To investigate whether myeloschisis is the direct cause of Chiari malformation and hydroceph...

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Main Authors: Sim, K. B., Hong, S. K., Cho, B. K., Choi, D. Y., Wang, K. C.
Format: Online
Language:English
Published: Korean Academy of Medical Sciences 1996
Online Access:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3054255/
id pubmed-3054255
recordtype oai_dc
spelling pubmed-30542552011-03-15 Experimentally induced Chiari-like malformation with myeloschisis in chick embryos. Sim, K. B. Hong, S. K. Cho, B. K. Choi, D. Y. Wang, K. C. Research Article Though several pathogenetic theories concerning the frequent association of Chiari malformation and hydrocephalus with myeloschisis have been suggested, none of them explains all the aspects of the disorder. To investigate whether myeloschisis is the direct cause of Chiari malformation and hydrocephalus or these conditions are the results of another basic event, we observed the morphological changes of the posterior cranial fossa and its components in the chick embryos with surgically induced myeloschisis. To make myeloschistic lesions, we opened the neural tube for a length of 9-11 somites in Hamburger and Hamilton stage 16-19 chick embryos. They were divided into cervicothoracic (C-T) and lumbosacral(L-S) groups according to the area of incision. The embryos were re-incubated until postoperative day 11. In the control group, embryos were incubated with the eggshell window open as their experimental counterparts. The survival rates of each group were as follows; 11% (9 survivors/85 operated embryos), 8% (7/83), and 17% (10/60) in the C-T, L-S and control groups, respectively. Myeloschisis positive rates were 100% in the operated groups and 0% in the control group. The heads of embryos were sectioned along the sagittal plane to observe the morphological changes in the posterior cranial fossa and its components. Of the survivors, five in the C-T group, two in the L-S group and six in the control group were available for light microscopic inspection. In the majority of embryos with myeloschisis, without difference between the C-T and L-S groups, the fourth ventricles were smaller than those of the control group and the subarachnoid spaces in the posterior cranial fossa were also narrower. In embryos with severe changes, the cerebellum displaced downward comparing with that of the control embryos. No evidence of hydrocephalus was present Though not always typical, morphological changes similar to Chiari malformation were observed in chick embryos with surgically induced myeloschisis. It suggests a strong direct causal relationship between the two conditions and supports the theories of derangements in cerebrospinal fluid dynamics rather than those of primary mesenchymal or neural origin as a pathogenetic mechanism of Chiari malformation. Korean Academy of Medical Sciences 1996-12 /pmc/articles/PMC3054255/ /pubmed/9008100 Text en
repository_type Open Access Journal
institution_category Foreign Institution
institution US National Center for Biotechnology Information
building NCBI PubMed
collection Online Access
language English
format Online
author Sim, K. B.
Hong, S. K.
Cho, B. K.
Choi, D. Y.
Wang, K. C.
spellingShingle Sim, K. B.
Hong, S. K.
Cho, B. K.
Choi, D. Y.
Wang, K. C.
Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.
author_facet Sim, K. B.
Hong, S. K.
Cho, B. K.
Choi, D. Y.
Wang, K. C.
author_sort Sim, K. B.
title Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.
title_short Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.
title_full Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.
title_fullStr Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.
title_full_unstemmed Experimentally induced Chiari-like malformation with myeloschisis in chick embryos.
title_sort experimentally induced chiari-like malformation with myeloschisis in chick embryos.
description Though several pathogenetic theories concerning the frequent association of Chiari malformation and hydrocephalus with myeloschisis have been suggested, none of them explains all the aspects of the disorder. To investigate whether myeloschisis is the direct cause of Chiari malformation and hydrocephalus or these conditions are the results of another basic event, we observed the morphological changes of the posterior cranial fossa and its components in the chick embryos with surgically induced myeloschisis. To make myeloschistic lesions, we opened the neural tube for a length of 9-11 somites in Hamburger and Hamilton stage 16-19 chick embryos. They were divided into cervicothoracic (C-T) and lumbosacral(L-S) groups according to the area of incision. The embryos were re-incubated until postoperative day 11. In the control group, embryos were incubated with the eggshell window open as their experimental counterparts. The survival rates of each group were as follows; 11% (9 survivors/85 operated embryos), 8% (7/83), and 17% (10/60) in the C-T, L-S and control groups, respectively. Myeloschisis positive rates were 100% in the operated groups and 0% in the control group. The heads of embryos were sectioned along the sagittal plane to observe the morphological changes in the posterior cranial fossa and its components. Of the survivors, five in the C-T group, two in the L-S group and six in the control group were available for light microscopic inspection. In the majority of embryos with myeloschisis, without difference between the C-T and L-S groups, the fourth ventricles were smaller than those of the control group and the subarachnoid spaces in the posterior cranial fossa were also narrower. In embryos with severe changes, the cerebellum displaced downward comparing with that of the control embryos. No evidence of hydrocephalus was present Though not always typical, morphological changes similar to Chiari malformation were observed in chick embryos with surgically induced myeloschisis. It suggests a strong direct causal relationship between the two conditions and supports the theories of derangements in cerebrospinal fluid dynamics rather than those of primary mesenchymal or neural origin as a pathogenetic mechanism of Chiari malformation.
publisher Korean Academy of Medical Sciences
publishDate 1996
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3054255/
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