Vagina layers

The oviducts are also known as the Fallopian tubes or uterine tubes. The wall of the oviduct consists of three layers a mucosa, a muscular layer and an outer layer of connective tissue. When the ovum is released by the ovary, it is taken up by the oviduct. The ends of the oviducts are not directly attached to the ovaries but open into the abdominal cavity close to them. The opening of each is funnel-shaped and surrounded by long finger-like projections, fimbriae, with ciliated epithelium which catch the ovum as it is released. The other ends open directly into the uteras. The lower end of the latter is known as the cervix and opens into the vagina. 

Papilloma. A benign epithelial neoplasm producing finger-like or verrucous projections from the epithelial surface. Parakeratosis. Persistence of the nuclei of the keratinocytes into the stratum corneum (horny layer) of the skin. Parakeratosis is normal in the epithelium of true mucous membrane of the mouth and vagina. Parkinson s disease. Neurological disorder characterized by hypokinesia, tremor, and muscular rigidity. 

Patton, D.L., et al. 2000. Epithelial cell layer thickness and immune cell populations in the normal human vagina at different stages of the menstrual cycle. Am J Obstet Gynecol 183 967. 

The vaginal fluid is also characterized by a certain enzymatic activity due to bacterial flora and enzymes present in the secretions and in the epithelium. The external and basal cell layers of the vagina express the majority of the enzymatic activity [2,5,9]. 

In postmenopausal women, the incidence of mitosis in the basal and parabasal layers and the number of small blood vessels decreases. The vaginal epithelium becomes extremely thin, cell boundaries in the surface are less distinct, the micro-ridges of the cells are dramatically reduced, and the vagina is often invaded with leukocytes. Naturally, this thinning of the epithelium leads to a substantial increase in the permeability of this tissue. 

Its mode of action seems to be along these lines. When the thin skin layers and mucus of the mouth, anus or vagina are damaged then, as in all cell damage, there is a large influx of white cells to combat any possible invaders. It is precisely this gathering of white cells, normally effective for killing off viruses or bacteria, that HIV (Human Immuno-deficiency Virus) attacks and takes over. 

Patton, D. L., Thwin, S. S., Meier, A., Hooton, T. M., Stapleton, A. E., and Eschenbach, D. A. (2000), Epithelial cell layer thickness and immune cell populations in the normal human vagina at different stages of the menstrual cycle, Am. J. Obstet. Gynecol., 183, 967-973. 

It has been found that the basal cells replicate continuously to provide a self-cleaning mechanism to the epithelial layer. Autoradiographic studies of cell proliferation were performed on normal human cervix and vagina. The turnover time, an indication of the time required for the replacement of the cell population, was determined from these studies. Results showed the basal layer to be relatively inactive with a turnover rate of 33 days, while active proliferation occurred in the parabasal layers with a turnover rate of 3 days. The intermediate and superficial layers were found to be inactive differentiating compartments. 

Vagina, N. S., Volymets, M. P. Thin-layer chromatography in inorganic analysis. II. Separation and determination of rate earths and other impurities during the analysis of lanthanide preparations of various degree of purity. Zh. Anal. Khim. 23, 521 (1968) C. A. 69,... 

The ventral border of the perirectal compartment represents the border between posterior and middle compartment. It differs in a craniocaudal direction, i. e. to the peritoneum of the recto-uterine pouch at a level with the cervix uteri and the fornix vaginae and to the posterior wall of the vagina more caudally. As we have recently shown [ 1,24,36] a two layered recto-... 

Fig. 1.7a,b. Computer-assisted reconstructions of a female fetus, a Oblique ventrolateral view, b Descending dorsoventral view, v, vagina Im, longitudinal muscular layer pr, puborectalis muscle eas, external anal sphincter is, internal sphincter pbo, pubic bone... 

On axial CT scans, the vagina is difficult to differentiate from the urethra (Fig. 12.1) and it is not possible to distinguish the vaginal epitheUum/mucus from the layers of the vaginal waU. 

Fig. 12.1a-c. CT anatomy of the normal vagina. a,b CT. c Sagittal CT reconstruction. CT anatomy of the vagina - middle third at the level of the urinary bladder (a) and distal third at the level of the urethra (b). The vagina has the same density as the walls of the bladder, urethra, and rectum and can be distinguished from these structures on CT by the presence of a small fat layer. For differentiation of the vagina, it is also helpful if the bladder is filled with urine and the rectum is filled with air... 

On Tl-weighted MR images with fat saturation,the vagina is of intermediate to low signal intensity and the mucosa, epithelium, and muscular layer cannot be distinguished (Fig. 12.2). 

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