MEDEGYPT
مدير المنتدى
عدد المساهمات : 259
 |  موضوع: female genital system (gynacology  الثلاثاء يونيو 09, 2009 5:09 pm | |
| center] Female Genital System[/center] points to be disscusied
Female External Genitalia|
|Female Internal Genitalia
mammary glands
Development of the Female Sexual & Reproductive Organs
Anatomy Vagina -
is a fibromascular tube which gives access to the cervical canal and uterus.
During sexual intercourse it envelopes the penis and during delivery the vagina is the birth canal for the infant.
During these functions the vaginal walls can constrict and dilate due to the presence of smooth muscles and fibroelastic tissue.
The adult vagina extends some 7-10 cm upwards and leaning towards the back. The vaginal orifice is
protected by a thin mucosal fold called the hymen, which is perforated at its center.
Vulva -
the external portion of the female reproductive organs. It surrounds the vaginal orifice (opening) and
consists of the vestibule, the hymen, the urethral opening and Skene& gland ducts
, the openings of the greater vestibular glands (Bartholin ducts),
two sets of lips or labia -
labia minora and majora, and the clitoris, the mons pubis and the perineum.
Mons Pubis
a prominent cushion of hair-bearing skin and subcutaneous fat overlying the pubic bone.
Labia Majora -
prominent folds of skin overlaying the deposits of subcutaneous fat, and characterized by the presence of pigmented and hair bearing skin just adjacent to the thighs.
The labia majora originates from the mons pubis anteriorly and merges with the perineal body posteriorly.
Labia Minora -
thin folds of hairless skin located between the labia majora on either side of the vaginal and urethral openings.
The skin of the labia minora is smooth and pigmented and is composed mainly of elastic fibers and blood vessels and possess a rich innervation.
Anteriorly the skin folds split to enclose the clitoris, forming an anterior prepuce and a posterior frenulum, and the posterior ends are united in a sharp fold known as the fourchette.
Vestibule -
the area between the labia minora and the vagina.
It extends from the clitoris to the posterior fourchette. Localised within the vestibule are the openings of the vagina, the urethra, the ducts of the Brtholin glands and the minor vestibular glands. The part of the vestibule between the vaginal orifice and the frenulum of the labia minora forms a shallow depression termed the vestibular fossa.
Hymen -
a thin and incomplete membrane of connective tissue at the junction of the vestibule and the vagina. Regular use of tampons or regular sexual intercourse will reduce the hymen to a series of irregular deviations around the vaginal opening termed carunculae myrtiformes.
Bartholin Glands -
the greater vestibular glands situated deeply within the posterior parts of the labia majora. Each gland lies just inferior and lateral to the bulbocavernosus muscle.
The main duct of each Bartholin gland opens at the lateral margin of the vagina in the lower half of the vestibule. The glands produce a clear secretion which is most noticeable during sexual arousal. The glands may be the site of infection and cysts formation at any age.
Minor vestibular glands (not shown in the diagram) - tubular structures commonly occurring around the fourchette in numbers varying from 1 to more than 100, the average number being 2-10.
Clitoris -
the erectile tissue that is the equivalent of the male penis. It is situated at the apex of the vestibule anteriorly. The glans of the clitoris is partly hidden by the prepuce.
Referrence:Female Genital System(Chinese Version)
The female genitourinary system consists of internal paired ovaries, uterine tubes, uterus, vagina, external mons pubis, labia majora, labia minora, clitoris, urethra, and perineal body.
Although the female urinary structures are anatomically separate from the genital structures, their anatomic proximity provides a means for cross-contamination and shared symptomatology between the two systems
Uterus Ronald A. Bergman, PhD Adel K. Afifi, MD, MS Ryosuke Miyauchi, MD Peer Review Status: Internally Peer Reviewed
--------------------------------------------------------------------------------
The chief anomalous conditions of the uterus are due to defective development or imperfect fusion of the m¨¹llerian ducts, which unite to form the usual organ. Arrested development of the lower part of these fetal canals accounts for the complete absence of the uterus and vagina. Depending on the extent to which failure of fusion occurs, all degrees of doubling are produced. In the most pronounced cases, in which the m¨¹llerian ducts remain separate throughout their entire length, two completely distinct uteri and vaginae may result, each set being capable of performing the functions of the normal organs. On the other hand, a slight indentation of the fundus may be the only evidence of imperfect union. Between these extremes all gradations occur: a) the body may be completely cleft (uterus bicornis), with or without divided cervix; b) the doubling may be partial and limited to branching of the fundus; or c) the faulty fusion may be manifested by only a partitution, more or less complete, that divides the uterine cavity into two compartments (uterus eptus), although the external form of the organ is almost or quite normal.
When, occuring with any of the variations listed above, one of the component m¨¹llerian ducts fail to keep pace in its growth, all degrees of symmetrical development may result, from complete suppression of one of the tubes in a bicornate uterus to unilateral diminution of the fundus. Subsequent arrest of what began as normal development may result in permanent retention of a fetal or infantile type of uterus.
Cases of congenital absence of the os uteri, tripartite uteri, uterine diverticula, and uterus have been reported.
Vagina Ronald A. Bergman, PhD Adel K. Afifi, MD, MS Ryosuke Miyauchi, MD Peer Review Status: Internally Peer Reviewed
--------------------------------------------------------------------------------
The most important variations are related to defective development and imperfect fusion of the component m¨¹llerian ducts, which are often associated with anomalies of the uterus. When these ducts fail to reach the urogenital sinus, the vagina (and often the uterus) may be absent.
Vaginal agenesis was first described by Realdus Columbus in 1572. Duplication, more or less complete, follows persistence of separate or imperfectly fused m¨¹llerian ducts. The doubling may not extend throughout the length of the vagina, but may be represented by an imperfect and partial septum, isolated bands, or a twin hymen.
Unequal development of the m¨¹llerian ducts accounts for the marked asymmetry occasionaly seen, notably in double vaginae, in which one canal may be very rudimentary, end blindly, or be essentially normal but doubled throughout.
A doubled vagina may be associated with a single uterus, although this condition is usually found in cases of doubled or bipartite uteri. In some instances, the cervices are doubled.
The vagina may be markedly foreshortened.
Reports of the vagina opening into the urethra, bladder, or rectum, or onto the abdominal wall in adults are very rare.
Pregnancy in a case of an anovaginal orifice (i.e., lack of a normal external vaginal opening) has been reported.
Mammary Gland Ronald A. Bergman, PhD Adel K. Afifi, MD, MS Ryosuke Miyauchi, MD Peer Review Status: Internally Peer Reviewed
--------------------------------------------------------------------------------
The mammae frequently develop asymmetrically, the right often being larger and lower than the left. While absence of one or both mammae is very rare, with or without associated absence of the nipple, an increase in their number is relatively common occurrence. The supernumerary mammae vary in the extent to which they are developed, being represented sometimes by well-formed accessory glands (polymastia) that may become functioning organs, but more often, particularly in the male subject. Only by rudimentary nipples (polythelia) or even pigmented areas suggesting areolae. In women, polythelia may be associated with greater or less development of glandular tissue.
Doubled nipples have been reported frequently. Hyperthelia is much more common than hypermastia.
The recorded frequency of polythelia in men (14%) is very questionable. A better estimate in healthy individuals is about 4-5% with no sex differences reported. The occurrence of rudimentary supernumerary nipples is undoubtedly more common than usually recognized. Renal variations accompanied polythelia in nine of 37 (27%) subjects studied.
The usual position of the accessory mammae is below and somewhat medial to the usual glands and corresponds to the mammary line in other animals. In some cases, they may be found above and laterally, in the axillary region, especially in Japanese subjects.
The number of accessory or supernumerary glands varies: three pairs in one case, five milk-secreting organs in another, and eight glands in both sexes (1-2% of females and males) have been recorded. They are often asymmetrically placed and not uniformly developed. Comparative studies of the mammae in "lower animals" and the disposition of the supernumerary organs in the human subject suggest the probability that remote human ancestors normally possessed more than two glands; the occasional occurrence of the variant mammae in positions anticipated by the milk-ridges, rudimentary organs sometimes occupy very unusual locations, including the back, lateral thorax, neck, shoulder, inner aspect of the arm, axilla, buttocks, hip, thigh and labium majus.
Massive hypertrophy has been reported, with a combined weight of 124 lbs, with one gland weighing 63 lbs in a 13-year-old girl whose remaing weight was less than the combined weight of the two glands. Excessively large breasts may lead to hyperesthesia in the ulnar nerve distribution in hands (a variant of thoracic outlet syndrome). Micromastia has also been reported.
Hermaphroditism Ronald A. Bergman, PhD Adel K. Afifi, MD, MS Ryosuke Miyauchi, MD Peer Review Status: Internally Peer Reviewed[u] [left] | |
|
