The science and art of obstetrics / by Theophilus Parvin.

  • Parvin, Theophilus, 1829-1898.
Date:
1895
Catalogue details

Licence: Public Domain Mark

Credit: The science and art of obstetrics / by Theophilus Parvin. Source: Wellcome Collection.

    55/693 (page 54)
    this vault is divided into two lateral culs-de-sac, distinguished as right and left, and one anterior and one posterior; the last is the deepest. liie vaginal is continuous with the vulval canal below: as the union between the two is made at the narrowest part of each, a strait is formed which is in some cases the cause of serious delay in childbirth The anterior and posterior walls of the vagina present transverse elevations those on the former being more prominent than those on the latter lhese elevations, sometimes improperly called rugce,1 are more distinct at the entrance of the vagina, and gradually lessen until they disappear a little above the middle of the canal • the so-called rugae on the pos- terior wall in many cases ascend higher than those on the anterior wall. Labor temporarily effaces them, and after it, though gradually reform- ing, they are never so distinct as in the nulliparous. Two longitudinal elevations are formed at the junction of the transverse ridges in the median line, one on the anterior, the other on the posterior vaginal wall, that on the former being the more prominent, which are called the vaginal columns, and also the columnce rugarum. The longitudinal and transverse elevations form what is called the lyre. Neither the' columns nor the rugae are directly opposite, and thus more complete apposition of the walls i3 secured. At the lowest portion of the anterior column a projection is observed, tuberculum vagince; this is important as a guide to the urethral opening, which is just above the tubercle. Fig. 24. Section of the Mucous Membrane of the Vagina, showing Cylindrical Cells. The walls of the vagina are from one-eighth to one-sixth of an inch, three to four millimetres, in thickness. They are composed of three coats or layers, the external fibrous, the middle muscular, which makes two-thirds of the thickness of the wall, and the internal mucous. The first is formed of connective tissue and elastic fibres; it contains large bloodvessel branches and nerve-tracts. It is in relation externally with the organs which encircle the vagina, and internally with the middle coat. The arraugement of the muscular fibres composing the middle coat is given differently by authors. According to Henle, the external layer is circular and the internal longitudinal; while Luschka gives a reverse disposition of these fibres, the longitudinal being external, the internal circular, and between the two oblique fibres are found. Tarnier describes the muscular fibres as inserted below in the ischio- pubic rami and continued above with the middle of the three muscular layers of the uterus; some extend into the utero-sacral ligaments, and i These projections have been regarded as simply folds of the mucous membrane which are effaced in coition, and especially in labor. But they are not at all similar to folds. They are pro- longations, elevated above the walls of the canal .... and do not contribute to enlargement of the vaginal cavity, but to coition.—Sappey.