Diseases of the nervous system / edited by Archibald Church.

Date:
1908
Catalogue details

Licence: In copyright

Credit: Diseases of the nervous system / edited by Archibald Church. Source: Wellcome Collection.

    29/1256 (page 1)
    THE MACROSCOPIC ANATOMY OF THE CENTRAL NERVOUS SYSTEM WITH SPECIAL REFERENCE TO THE PHYSIOLOGY OF THE BRAIN By M. ROT.HMANN, Berlin At the beginning of the twentieth century the study of the macroscopic anatomy of the central nervous system is most necessary. As in many other departments of science which are apparently devoid of clinical interest, here also in the victorious progress of clinical research the necessity has arisen to reveal to the clinician such exact knowledge of the anatomical relations of the central nervous system as in preceding decades only the specialist in this branch of medicine was expected to acquire. Not merely because the enor- mous advance in the study of the physiology and pathology of the brain and spinal cord now enable us almost daily to localize exactly the manifold affec- tions of the central nervous system, but surgery has very recently found its realm greatly enlarged in that it now searches for an abscess deep within the brain or locates a tumor of the brain or spinal cord by methods of diagno- sis which are constantly becoming more certain; it successfully removes these, or even a cicatrix upon the surface of the brain which has been the cause of severe epileptic convulsions. In all of these diagnoses and operations accu- rate knowledge of the individual parts of the central nervous system, their blood supply, their position in the skull and vertebral column, is absolutely necessary. In addition, one of the greatest contributions to our clinical armamentarium, Quincke’s method of lumbar puncture, the importance of which is constantly proven, in its various modifications can be practically utilized only when we fully understand the position of the spinal cord and its membranes within the canal of the vertebral column. If the relations of the fully developed, human, central nervous system are to be correctly appreciated, its embryologic structure must be under- stood and the simpler forms in lower animals must be compared with these. The central nervous system is developed from the ectoderm. The medullary plates arising from the originally single-layered epithelium along the median line of the body grow toward each other, then close and form the embryonic medullary tube, which dorsally for some time reveals a space. Separated from this embryonic medullary tube is a ganglion crest, from which the ganglia of the head and spine arise, and a sympathetic layer, both of which subsequently develop spontaneously. In the lowest vertebrate animals known to us, the amphioxus, in which the brain is merelv indicated by a slight thickening at the anterior end of the embryonic medullary tube, the central nervous system remains permanently in this stage. In all other vertebrates,