Things i think i should know topic 1 - 3 Flashcards
List the advantages of TVS
- No need for a full bladder
- Fewer artifacts as anterior abdomen attenuation is avoided
- Closer contact with pelvic organs means higher frequency and better resolution
- Dynamic assessment i.e. push into ovary
- Examination of patients who are unable to fill their bladder
- Examination of obese patients
- Evaluation of a retroverted or retroflexed uterus
- Better characterization of the internal characteristics of a pelvic mass
- Better detail of a pelvic lesion
- Better detail of the endometrium
List the disadvantages of TVS
- There are not many
- High frequency means limited depth though usually sufficent
- Due to positioning against the uterus field of view may be limited i.e. cannot push in further
- Imaging of specific organs rather than a global view of the region (uterus, ovaries, adnexa)
- Transducer movement can be limited by the confines of the vagina.
- Urine in the bladder may displace organs or masses outside the field of view.
- Fundal masses, such as leiomyomata, may be difficult to evaluate or can even be missed transvaginally and may require transabdominal sonography to visualise them or to best evaluate their size.
- invasive
- emotionally sensitive
List some causes of Endometrial Thickness in Premenopausal Women
- submucosal fibroid
- endometrial polyp
- endometrial hyperplasia
- trophoblastic disease
- uterine synechiae or adhesions
- early intrauterine pregnancy and collections of blood or pus due to either infection, cervical cancer or cervical stenosis.
List some causes of Endometrial Thickness in The Postmenopausal Woman
- Endometrium measuring > 8mm in thickness tho some debate
- Thickening indicates an abnormal endometrium.
- most significant reason is endometrial carcinoma.
- Ultrasonography cannot distinguish benign from malignant endometrial growth.
How does the endometrium appear during menstruation?
Early - hypoechoic central line representing blood and tissue surrounded by a hyperechoic endometrial echo.
Late - the hypoechoic echo that represents blood disappears and the endometrium appears as a single line.
How does the endometrium appear during the proliferative phase?
- endometrium appears as a single thin stripe representing the cavity
- a hypoechoic halo encompassing it
- creating what is called the triple stripe appearance.
- The thin surrounding hyperechoic layer represents the basalis.
How does the endometrium appear during the proliferative phase?
at its greatest thickness and echogenicity.
What are some indications for sonohysterography?
- not routinely needed
- done on day 4-10 of cycle
1. endometrium not adequately evaluated by TVS or TAS
2. women with abnormal bleeding when a focal lesion is not visualized sonographically
3. evauation of endometrial or intracavitary abnormalities detected by TVS
4. infertility
5. suspected congenital uterine malformations
6. evaluation of women taking tamoxifen
What are the four functions of the reproductive system?
- to produce eggs and sperm cells
- to transport and sustain these cells
- to nurture developing offspring
- to produce hormones.
What is the normal size of the uterus?
- 8 cm in length, 5 cm in width, and 4 cm in anteroposterior (AP) diameter.
- extra 1-2cm in each dimension after kids
- Atrophy after menopause
List the vessels of the uterus from outer to inner
- Arcuate arteries
- between the outer and intermediate layers of the myometrium
- branch into the radial arteries
- These run in the intermediate layer to the level of the inner layer
- branch into the spiral arteries
- These enter the endometrium and supply the functional layer
How do you differentiate the hypoechoic glandular area from a hypoechoic mass in the cervix?
- The uniform elongated nature of this finding should help distinguish it from a true mass.
Why might a Nabothian cyst have internal echoes?
Proteinaceous material or haemorrhage
What is the name for cervical folds?
Plicae palmatae
What are possible normal sources of fluid in the POD?
- blood or fluid caused by follicular rupture
- blood from retrograde menstruation
- increased capillary permeability of the ovarian surface caused by the influence of estrogen.
What are some pathological sources of fluid in the POD?
- generalized ascites
- blood resulting from a ruptured ectopic pregnancy or hemorrhagic cyst
- pus from infection.
How can sonography aid in identifying type of fluid in the POD?
- blood, pus, mucin, and malignant exudates usually contain echoes within the fluid
- serous fluid (either physiologic or pathologic) is usually anechoic.
- Clotted blood may be very echogenic, mimicking a solid mass.
If the uterus is lying to one side where might you find the ipsilateral ovary?
superior to the uterine fundus
Where are the ovaries most commonly found?
Waldeyer fossa
What size are the normal ovaries?
Up to 22mL in the reproductive female
How does the early corpus luteum appear?
- contains internal low-level echoes consistent with hemorrhage
- crenulated thick walled cyst
- peripheral colour doppler signals
How does the late corpus luteum appear?
collapsed
How does a post menopausal ovary appear?
Small, hypoechoic, lacks follicles
1.2-5.8mL
>8mL abnormal
What sonographic signs indicate ovulation has taken place?
- The disappearance of the dominant follicle with associated free fluid in the pelvis signifies ovulation.
What is a corpus albicans?
- As the corpus luteum ages it collapses and becomes a more solid, fatty structure, a corpus albicans, not well visualised on sonography.
Comment on unilocular post menopausal cysts
- low incidence of malignancy in less than 5 cm in diameter and without septations or solid components
- ovarian cysts less than 7 cm and greater than 1 cm in diameter be followed by serial yearly sonographic examinations without surgical intervention
- Unless there is an increase in size or a change in the characteristics of the lesion.
When is surgery recommended in a post menopausal cyst?
- greater than 7 cm and for those containing multiple internal septations or one or more solid nodules.
What is the role of FSH?
stimulates the ovarian follicles to develop and produce estrogens.
When does estrogen rise to a peak?
just before the luteinizing hormone (LH) surge.
When does ovulation usually occur in relation to hormones?
24 to 36 hours after the LH surge.
What happens to hormones if fertilisation does not occur?
blood levels of circulating estrogens and progesterone fall
What does the fall of estrogens and progesterone do to the endometirum?
causes the endometrium to regress and menstruation to start again
What is GnRH?
Gonadotropin hormone-releasing hormone (GnRH), A hormone made by a part of the brain called the hypothalamus
What does GnRH do?
causes the pituitary gland in the brain to make and secrete the hormones luteinizing hormone (LH) and follicle-stimulating hormone (FSH)
What regulates GnRH?
Steroid feedback regulates GnRH release. For most of the reproductive cycle, estradiol negative feedback suppresses GnRH release
What is the effect of estrogen and progesterone during the cycle?
- Produced by the ovarian follicles and corpus luteum
* Produce cyclic changes in the endometrium
What are the approximate timing of cycle phases?
menstrual 1-5
Proliferative 6 - 15
Luteal/secretory 16 - 28
What happens during the menstrual phase?
- functional layer of the uterine wall is sloughed off with the menstrual flow
- lasts 4 to 5 days
- After menstruation, the eroded endometrium is thin
What happens during the proliferative phase?
- Lasts approximately 9 days
- coincides with the growth of ovarian follicles
- controlled by estrogen secreted by the follicles
- two to three-fold increase in the thickness of the endometrium
What happens during the luteal (secretory) phase?
secretory phase)
• lasts approximately 13 days
• coincides with the formation, functioning, and growth of the corpus luteum.
• The progesterone produced by the corpus luteum stimulates the glandular epithelium to secrete a glycogen-rich material
• endometrium thickens because of the influence of progesterone and estrogen from the corpus luteum
What happens when fertilisation does not occur?
- The corpora lutea degenerate
- Estrogen and progesterone levels fall and the secretory endometrium enters an ischemic phase
- Menstruation occurs
What happens if fertilisation does occur?
- formation of a blastocyst begins
- blastocyst begins to implant in the endometrium on approximately the sixth day of the luteal phase
- Human chorionic gonadotropin, a hormone produced by the syncytiotrophoblast, keeps the corpora lutea secreting estrogens and progesterone
- The luteal phase continues and menstruation does not occur.
Briefly describe endometrial appearance throughout the cycle
- Menstrual phase: a thin, single echogenic line, 0.5-1 mm.
- Proliferative phase: hypoechoic thickening, 4-8 mm.
- Secretory phase: hyperechoic thickening 7-14 mm.
Briefly describe the post menopausal endometrium
- No HRT: atrophic, single echogenic line, < 5 mm.
* With HRT: single echogenic line, < 8 mm.
List the effects of hormones on the post menopausal endometrium
unopposed oestrogen - thick heterogeneous
daily estrogen/progesterone - thin atrophic
sequential estrogen/progesterone - thickness varies with phase of cycle
tamoxifen - thick cystic space
List the sonographic appearance of the pre menopausal ovary
- Follicular phase: many follicles (5-11) increase in size until day 8-9, then one follicle becomes dominant; all others become atretic.
- Pre-ovulatory: follicle measuring 20-25 mm.
- Luteal phase: corpus luteum, a 20 mm irregular hypoechoic or isoechoic cyst often containing low level echoes. There can be a typical ‘ring’ colour flow.
Post menopausal ovary appearance
- No HRT: atrophy, no follicles, decrease in size.
* With HRT: atrophy, no follicles, decrease in size.
What is PMB?
Post menstrual bleeding
What is IMB/metrorrhagia?
intermenstrual bleeding
What is Menometrorrhagia?
prolonged menstrual flow and intermenstrual bleeding.
What is VE?
Vaginal examination
What is dysmennorhia?
painful periods
What is primary amenorrhea?
refers to females who fail to undergo menarche
What is secondary amenhorrea?
: the absence of menstrual periods for six months, or a length of time equivalent to three normal menstrual cycles, in a female who has been menstruating previously
What is oligomennorhea?
the occasional occurrence of menses.
What is polymennorhea?
refers to menses at intervals of less than 21 days.
What is Hypermenorrhoea or menorrhagia?
prolonged and increased uterine bleeding at regular intervals.
What is Dyspareunia?
Pain during sex
What is PCB?
Post coital bleeding
What is Mittelschmerz?
intermenstrual pain linked with the phenomenon of ovulation, sometimes associated with a small amount of brown discharge.
Can you explain why exogenous administration of oestrogen and progestogen inhibits ovulation?
- Both oestrogen and progestogen have an inhibitory effect on the hypothalamus and pituitary resulting in an inhibition of gonadotropin production.
- Low FSH results in depressed follicular development
- the dominant action for contraception is LH inhibition. - If there is no mid-cycle LH peak, ovulation will be inhibited even if follicular development occurs.
What does oestrogen do in the OCP?
- Prevents ovulation by LH inhibition
* Depressed FSH also depresses follicular development
What does progesterone do in the OCP?
- creates an endometrial lining that resists implantation
- thickens cervical mucus, retarding sperm entry into the upper female reproductive tract
- supplement the antiovulatory effects of estrogen
- make pregnancy unlikely should ovulation occur.
How does the ovary appear on OCP?
- homogeneous structure
- without a dominant follicle (sometimes will be present as patient will ovulate)
- even the small anechoic nonovulatory immature follicles may not be present
How will the endometrium appear on OCP?
Thin echogenic line
What clinical problems does OCP suppress?
• Conditions associated with ovulation (ectopic pregnancy and ovarian cysts)
• pelvic inflammatory disease (PID)
• Iron deficiency anaemia is less likely since menstrual bleeding is decreased
• decreased menstrual symptoms
• improvement in acne.
- reduces the risk of developing uterine myomata
- both ovarian and endometrial cancers are about half as common
Briefly describe the hormonal changes of menopause
- permanent cessation of menstruation occurs following the loss of ovarian activity
- gonadotropins, FSH and LH, will rise in an attempt to stimulate more follicles
- Despite this increase in FSH and LH, oestrogen production by the ovaries does not continue beyond the menopause.
What are the benefits of HRT?
- give oestrogen in order to reduce all the effects of oestrogen deprivation
- especially osteoporosis and cardiovascular disease
- Oestrogen replacement alone dramatically increases the risk of endometrial cancer
- risk can be eliminated by the addition of progestogen
- HRT therefore mostly refers to a combination of oestrogen and progestogen.
What is tamoxifen citrate?
- orally administered
- non-steroidal
- anti-oestrogen agent
- used for the treatment of oestrogen receptor positive breast cancer
- been found to prevent breast cancer in some high-risk populations
- weak oestrogen agonist in postmenopausal endometrial tissue
How does an endometrium on tamoxifen appear?
- nonspecific
- similar to those described in hyperplasia, polyps, and carcinoma.
- Cystic changes within the thickened endometrium are frequently seen
- Polyps are frequently present and can be quite large
- cystic changes are subendometrial in location and represent reactivation of adenomyosis in the inner layer of myometrium
