The healing of arteries after ligature in man and animals / by J. Collins Warren.

  • Warren, John Collins, 1842-1927.
Date:
1886
Catalogue details

Licence: Public Domain Mark

Credit: The healing of arteries after ligature in man and animals / by J. Collins Warren. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    At the aortic opening the intima narrows rapidly on either side; at its upper margin the aortic wall makes a sharp curve upward, when seen in longitudinal-vertical sections, to form the lower curve of the aortic arch. Here a thin layer of cells lying upon the elastic lamina, which is well defined, forms the intima aortae. The walls of the aorta, at the lower margin of the opening, are thicker, and are continuous in a nearly straight line with the tissue of the ductus; the tissues of the coats of the aorta and ductus are interwoven at this point, and those of the ductus are spread out in a fan-like shape, and are lost in the different layers of the wall of the aorta. The elastic lamina of the aorta does not form here a continuous layer, as above, but is broken into several more or less parallel layers. According to Thoma, that portion of the wall which lies inside of the principal elastic layer, belongs to the intima, and is described by him as the musculo-elastic layer of the intima which forms a rein- forcement to the wall at this particular point. A similar arrangement of the elastic lamina is found elsewhere in the aorta, and it would seem to have no significance at this spot further than as an indica- tion of the tendency of the elastic tissue to form less of a limiting membrane in the neighborhood of the ductus, where all layers are ill defined. The intima of the ductus narrows rapidly, as it emerges at the lower border, and becomes continuous with a simi- lar layer of cells, here appearing as connective tissue cells, which form a narrow layer in the intima of the descending aorta. This layer was traced about half an inch below the opening of the duc- tus, at various periods from birth up to adult life, but was not found to form the thick layer described by Thoma as lining the interior of the aorta between this point and the iliac artery after birth. The arrangement of the walls of the pulmonary artery resembles that seen at the aortic opening, but in a reverse order. Here, the upper wall is the thicker, and it receives the tissues of the upper wall of the ductus which are freely interlaced with it. The differ- ence between the two margins of the pulmonary opening is not so marked as at the aortic end. A few weeks after birth a very marked change has taken place in all the tissues of the ductus, which appear to be now undergoing hyaline degeneration, preparatory to absorption. The outermost walls alone remain, but it is not certain whether the structures, still preserved from degeneration, should not be regarded as belong- ing to the aorta and pulmonary artery. A few weeks later, this outer wall is found to have become greatly strengthened, and now