ANATOMY Flashcards
Synonym of VULVA
PUDENDUM
Female external genital organs/ Vulva includes
Mons veneris Labia majora Labia minora Clitoris Vestibule Perineum
Mons veneris/ pubis
Subcutaneous adipose connective tissue, adult: covered by hair
Labia majora
Lateral boundary of vulva
Fold of skin and subcutaneous tissue
Squamous epithelium
Sebaceous glands, sweat glands and hair follicles
Beneath skin: adipose tissue richly supplied by venous plexus: HEMATOMA IF INJURED DURING CHILDBIRTH
Inner surface hairless
Homologous: scrotum
Round ligaments terminate at its anterior end
Join to form posterior commissure in front of anus
Labia minora
Thick skin folds devoid of fat just inside the labia majora
Connective tissue, sebaceous glands, erectile muscle fibers, vessels and nerves
Devoid of hair follicles
Anteriorly divide to enclose clitoris, form prepuce and frenulum anteriorly and posteriorly respectively
Posteriorly fuse to form fourchette USUALLY INJURED DURING CHILDBIRTH
Homologous: ventral aspect of penis
Clitoris
Cylindrical erectile body measuring 2.5 cm
Location: most anterior part of vulva
Consists: Glans( squamous epithelium+ nerves), body and two crura
Vessels: connected to vestibular bulb, LIABLE TO INJURY DURING CHILDBIRTH
Attached: undersurface of symphysis pubis by suspensory ligament
Analogous: penis
Vestibule
Triangular area
Bounded Ant clitoris, Lat labia minora Post fourchette
4 openings
Urethral: anteriorly, 1-1.5 cm below pubic symphysis in the midline, paraurethral ducts open in post wall or directly onto vestibule
Vaginal: large, posterior, midline
Strat squam
Hymen guards opening
Virgin+ Nulliparous: covered by labia minora
Ruptures with sex, lacerated during childbirth and represented by cicatrized nodules CARUNCULAE MYRTIFORMIS
Bartholin gland ducts
Bartholin Glands
2 pea-sized
Located in superficial perineal pouch close to posterior end of vestibular bulb
Secrete alkaline mucus when sexually aroused, helped by contraction of bulbocavernosus
Lined by columnar epi, racemose gland
Duct 2 cm opens at junction of ant 2/3 and post 1/3 of vestibule in groove between hymen and labia minora, lined by columnar epi and strat squam(near opening)
Homologous: bulbourethral gland
Vestibular bulbs
2 elongated masses of erectile tissue within the mucous membrane of vestibule on either side of vaginal orifice
Incorporated within bulbocavernosus
Homologous with bulb of penis and corpus spongiosum
Vagina
Fibromusculomembranous sheath
Communicates uterine cavity and vulva
Canal for copulation, menstrual flow and birth
Directed upwards and backwards, 45* with horizontal in erect position, parallel to plane of pelvic inlet
4 walls, ant 7 cm post 9 cm and 3 lateral, H shaped on transverse section
4 fornices due to projection of cervix through anterior wall
Relations of Vagina
ANT
Upper 1/3 UB
Lower 2/3 Urethra
POST
Upper 1/3 Pouch of Douglas
Middle 1/3 Rectum separated by rectovaginal septum
Lower /3 Anal canal separated by perineal body
LAT
Upper 1/3 Pelvic cellular tissue
Middle 1/3 blended with Levator ani
Lower 1/3 (3B) Vestibular bulb, Bartholin glands and Bulbocavernosus
Vaginal Epithelial changes
Birth-14 days: Strat squam due to maternal estrogen
Pre puberty to post menopause: Few layered
Puberty to menopause: Strat squam devoid of glands; basal cells, intermediate cells and superficial cornified cells. Intermediate and superficial cells have glycogen. Cells extend up to squamnocolumnar junction
Vaginal Secretion
Acidic ph 4-5.5
Highest ph: upper vagina due to mixing of cervical fluid
More acidic: prior to menstruation or middle of menstrual cycle, pregnancy, sexual excitement
Contents
Epithelial debris, tissue fluid, leukocytes, proteins, lactic acid produced by Doderlein’s bacilli
Doderlein’s bacilli
GP rods, Anaerobic in acidic media
Convert glycogen to lactic acid in the vagina
Presence depends on estrogen, comes from intestines
Present 3 days after birth- 14th day
Reappears in puberty
Uterine changes with age
Birth: uterus in false pelvis + long cervix
Child: uterus:cervix= 2:1
Puberty: uterus:cervix= 1:2 to 1:3
Post menopause: uterus atrophies
Uterus dimensions
Length 8cm Breadth 5cm at fundus Wall thickness 1.5 cm Isthmus 0.5cm Cervix 2.5 cm; supravaginaland vaginal parts each 1.25cm
Uterine cavity dimensions
Fundus: no cavity
Body 3.5cm triangular on coronal section with apex downwards
Cervix 2.5 cm
Total 6-7cm
Uterus
Perimetrium: serous coat absent on lateral borders
Myometrium: thick smooth muscles, outer longitudinal, middle interlacing and inner circular
Endometrium: lamina propria with stroma: glands (non ciliated secretory columnar epi), blood vessels and nerves AND surface epi (single layer of ciliated columnar epi)
Cervix histology
EPITHELIAL LINING
- ARBOR VITAE UTERI
median ridge anteriorly and posteriorly from which transverse folds radiate
Lined: columnar epi with basal nuclei single layer, ciliated at folds, reserve cuboidal cells
Stroma with fibrous CT and complex racemose glands lined by secretory columnar epi - PORTIO VAGINALIS
Lining: strat squam upto external os where changes to columnar - TRANSITIONAL ZONE
1-10mm
Endocervical stroma and glands, histology varies with estrogen, irritation from infection and trauma
Susceptible to dysplasia, metaplasia and carcinoma
