Ectropion refers to the eversion of the columnar epithelium onto the . canal is lined by the columnar epithelium (sometimes referred to as glandular epithelium). Eversion Glandular PDF – Free download as PDF ), Text ) or read online for free. Eversion-glandular-pdf. 6 Jul called cervical erosion, but it is. La conización es el tratamiento de referencia de las lesiones de alto grado del a las modificaciones de las propiedades del epitelio glandular y corolar de la.
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An introduction to the anatomy of the uterine cervix Colposcopy and treatment of cervical intraepithelial neoplasia: A thorough understanding of the anatomy and physiology of the cervix is absolutely essential for effective colposcopic practice.
This chapter deals with the gross and microscopic anatomy of the uterine cervix and the physiology of the transformation zone. The cervix is the lower fibromuscular portion of the uterus. It is cylindrical or conical in shape, and measures 3 to 4 cm in length, and 2.
It is supported by the cardinal and uterosacral ligaments, which stretch between the lateral and posterior portions of the cervix and the walls of the bony pelvis. The lower half of the cervix, called the portio vaginalis, protrudes into the vagina through its anterior wall, and the upper half remains above the vagina Figure 1.
The portio vaginalis opens into the vagina through an orifice called the external os. In parous women, it is bulky and the external os appears as a wide, gaping, transverse slit.
In nulliparous women, the external os resembles a small circular opening in the centre of the cervix. The supravaginal portion meets with the muscular body of the uterus at the internal cervical os.
The portion of the cervix lying exterior to the external os is called the ectocervix. This is the portion of the cervix that is readily visible on speculum examination.
The portion proximal to the external os is called the endocervix and the external os needs to be stretched or dilated to view this portion of the cervix. The endocervical canal, which traverses the endocervix, connects the uterine cavity with the vagina and extends from the internal to the external os, where it opens into the vagina.
It is widest in women in the reproductive age group, when it measures mm in width. The space surrounding the cervix in the vaginal cavity is called the vaginal fornix.
The part of the fornix between the cervix and the lateral vaginal walls is called the lateral fornix; the portions between the anterior and posterior walls of the vagina and the cervix are termed the anterior and posterior fornix, respectively. The stroma of the cervix is composed of dense, fibro-muscular tissue through which vascular, lymphatic and nerve supplies to the cervix pass and form a complex plexus.
The arterial supply of the cervix is derived from internal iliac arteries through the cervical and vaginal branches of the uterine arteries.
The veins of the cervix run parallel to the arteries and drain into the hypogastric venous plexus. The lymphatic glwndular from the cervix drain into the common, external and internal iliac nodes, obturator and the parametrial nodes. The nerve supply to the cervix is derived from the hypogastric plexus.
The endocervix has extensive sensory nerve endings, while there are very few in the ectocervix. Hence, procedures such as biopsy, electrocoagulation and cryotherapy are well tolerated in most women without local anaesthesia. Since sympathetic and parasympathetic fibres are also abundant in the endocervix, dilatation and curettage of the endocervix may occasionally lead to a vasovagal reaction. The cervix is covered by both stratified non-keratinizing squamous eversjon columnar epithelium.
These two types of epithelium meet at the squamocolumnar evdrsion. Gross anatomy of the u Stratified non-keratinizing squamous epithelium. Normally, a large area of ectocervix is covered by a stratified, non-keratinizing, glycogen-containing squamous epithelium. It is opaque, has multiple layers of cells Figure 1.
This epithelium may be native to the site formed during embryonic life, which glandulat called the native or original squamous epithelium, or it may have been newly formed as metaplastic squamous epithelium in early adult life. Tratakiento premenopausal women, the original squamous epithelium is pinkish in colour, whereas the newly formed metaplastic squamous epithelium looks somewhat pinkish-white on visual examination.
The histological architecture of the squamous epithelium of the cervix reveals, at the bottom, a single layer of round basal cells with a large dark-staining nuclei and little cytoplasm, attached to the basement membrane Figure 1. The basement membrane separates the epithelium from the underlying stroma. The epithelial-stromal junction is usually straight. Sometimes it is slightly undulating with short projections of stroma at regular intervals. These stromal projections are called papillae.
The parts of the epithelium between the papillae are called rete pegs. The basal cells divide and mature to form the next few layers of cells called parabasal cells, which also have relatively large dark-staining nuclei and greenish-blue basophilic cytoplasm. Further differentiation and maturation of these cells leads to the intermediate layers of polygonal cells with abundant cytoplasm and small round nuclei.
These cells form a basket-weave pattern. With further maturation, the large and markedly flattened cells with small, dense, pyknotic nuclei and transparent cytoplasm of the superficial layers are formed.
EVERSION GLANDULAR PDF
Tratamiengo, from the basal to the superficial layer, these cells undergo an increase in size and a reduction of nuclear size. Glycogenation of the intermediate and superficial layers is a sign of normal maturation and development of the squamous epithelium.
Abnormal or altered maturation is characterized by a lack of glycogen production. The maturation of the squamous epithelium of the cervix is dependent on estrogen, the female hormone. If estrogen is lacking, full maturation and glycogenation does not take place. Hence, after menopause, the cells do not mature beyond the parabasal layer and do not accumulate as multiple layers of flat cells. Consequently, the epithelium becomes thin and atrophic. On visual examination, it appears pale, with subepithelial petechial haemorrhagic spots, as it is easily prone to trauma.
The endocervical canal is lined by the columnar epithelium sometimes referred tragamiento as glandular epithelium.
It is composed of a single layer of tall cells with dark-staining nuclei close to the basement membrane Figure 1. Because of its single layer of cells, it is much shorter in height than the stratified squamous epithelium of the cervix.
On visual examination, it appears reddish in colour because the thin single cell layer allows the coloration of the underlying vasculature in the stroma to be seen more evesion. At its distal or upper limit, it merges with the endometrial epithelium in the lower part of the body of the uterus. At its proximal or lower limit, it meets with the squamous epithelium at the squamocolumnar junction.
The columnar epithelium does not form a flattened surface in the cervical canal, but is thrown into multiple longitudinal folds protruding into the lumen of the canal, giving rise to papillary projections. It forms several invaginations into the substance of the cervical stroma, resulting in the formation of endocervical crypts sometimes referred to as endocervical glands Figure 1. The crypts may traverse as far as mm from the surface of the cervix. This complex architecture, consisting of mucosal folds and crypts, gives the columnar epithelium a grainy appearance on visual inspection.
A localized overgrowth of the endocervical columnar epithelium may occasionally be visible as a reddish mass protruding from the external os on visual examination of the cervix. This is called a cervical polyp Figure 1. It usually begins as a localized enlargement of gkandular single columnar papilla and appears as a mass as it enlarges.
It is composed of tratamienot core of endocervical stroma lined by the columnar epithelium with underlying crypts.
Occasionally, multiple polyps may arise from the columnar epithelium. Glycogenation and mitoses are absent in the columnar epithelium.
Crypts of columnar epi The squamocolumnar junction Figures 1. During childhood and perimenarche, the original squamocolumnar junction is located at, or very close to, the external os Figure 1. After puberty and during the reproductive period, the female genital organs grow under the influence of estrogen.
EVERSION GLANDULAR PDF
Thus, the cervix swells and enlarges and the endocervical canal elongates. This leads to the eversion of the columnar epithelium of the lower part of the endocervical canal on to the ectocervix Figure 1. This condition is called ectropion or ectopy, which is visible as a strikingly reddish-looking ectocervix on visual inspection Figure 1.
Thus the original squamocolumnar junction is located on the ectocervix, far away from the external os Figures rversion. Ectropion becomes much more pronounced during pregnancy. The buffer action of the mucus covering the columnar cells is interfered with when the everted columnar epithelium in ectropion is tratamiebto to the acidic vaginal environment.
This tratamiemto to the destruction and eventual replacement of the columnar epithelium by the newly formed metaplastic squamous epithelium. Metaplasia refers to the change or replacement of one type of epithelium by another. The metaplastic process mostly starts at the original squamocolumnar junction and proceeds centripetally towards the external os through the reproductive period to perimenopause.
Thus, a new squamocolumnar junction is formed between the newly formed metaplastic squamous epithelium and the columnar epithelium remaining everted onto the ectocervix Figures 1. As the woman passes from the reproductive to the perimenopausal age group, wversion location of the new squamocolumnar junction progressively moves on the ectocervix towards the external os Figures 1.
Hence, eversionn is located at variable distances from the external os, as a result of the progressive formation of the new metaplastic squamous epithelium in the exposed areas of the columnar epithelium in the ectocervix. From the perimenopausal period and after the onset of menopause, the cervix shrinks due the lack of estrogen, and consequently, the movement of the new squamocolumnar junction towards the external os and into the endocervical canal is accelerated Figures 1.
In postmenopausal women, the new squamocolumnar junction is often invisible on visual examination Figures eeversion. The new squamocolumnar junction is hereafter eversio referred to as squamocolumnar junction in this manual.
Reference to the original squamocolumnar junction will be explicitly made as trratamiento original squamocolumnar junction. Location of the squamocolumnar junction SCJ and transformation zone; a before menarche; b after puberty and at early reproductive age; c in a woman in her 30s; d in a perimenopausal woman; e in a postmenopausal woman.
Location of the squamo Location of squamocolumnar junction SCJ a original squamocolumnar junction SCJ in a young woman in the early reproductive age group.
Chapter 1: An introduction to the anatomy of the uterine cervix
The SCJ is located far away from the external os. Note the presence of everted columnar epithelium occupying a large portion of the ectocervix producing ectropion. Mature metaplastic squamous epithelium occupies most of the ectocervix. Ectropion or ectopy is defined as the presence of everted endocervical columnar epithelium on the ectocervix.
It appears as a large reddish area on the ectocervix surrounding the external os Figures 1. The eversion of the columnar epithelium is more pronounced on the anterior and posterior lips of the ectocervix and less on the lateral lips.
Occasionally the columnar epithelium extends into the vaginal fornix. The whole mucosa including the crypts and the supporting stroma is displaced in ectropion.