Flashcards in Ultrasound imaging in gynaecology Deck (39):
How does an ultrasounds transducer work?
Piezoelectric crystal in the transducer.
Electrodes apply an alternating potential difference across the crystal.
The crystal grows and shrinks depending on the voltage run through it.
Running alternating current through it causes vibration at a high speed and production of an US wave.
This sound is the reflected back to the PE crystal converting sound to electrical energy and then to photo energy.
What is the Doppler effect?
The shift between emitted and observed frequency of sound.
What colour is emitted by objects moving away?
What colour is emitted by object moving towards?
What do different numbers of follicles in the ovary relate to?
2-3 = perimenopausal
3-5 = low follicle production
5-11 = normal
11+ = PCO
What does the endometrium look like shortly after menses?
A thin white line.
What does the endometrium look like during the mid-late proliferative phase?
Thick and manifests as a triple layer appearance.
What does the endometrium look like a day before ovulation?
Still has thick triple layer appearance but also has thick white line surrounding it which is likely to reflect more progesterone production from the dominant follicle.
What does the endometrium look like in the luteal phase of the cycle?
thick and homogenously hyperechoic (brighter than normal).
What is the size of a follicle during the early follicular phase?
less than 8mm in size. multiple present.
What is the size of a mid follicular follicle?
Dominant follicle present ahead of other follicles.
What is the appearance of a CL?
cystic or solid collapsed OR full appearance with irregular edge and shadows within the cyst. Irregularity of edges due to the presence of progesterone.
What is classical as 21 days?
What is the Resistance Index?
A-B/Mean Difference of the highest and lowest value divided by the mean in one cardiac cycle.
What is the Pulsatility Index?
A/B ratio indicates peripheral resistance
What is Resistance Index Absence/Reversal
Increase peripheral resistance causes diminution and then loss of blood flow.
What is the adnexa?
Part joining fallopian tubes and ovaries.
List structures that are looked for in the uterus.
- Polyps - tag in the endometrium. contains myometrium.
- Fibroids - muscle knots.
- Uterine malformation
- Location of pregnancy
What does SIS stand for?
Saline infusion solegraphy.
What does HyCoSy stand for?
Hystero-salpingo contrast sonography
When can polpys usually be visualised on an US?
When the endometrium has 3x layers.
What does TUI mean?
Targetted Ultrasound Initiative.
How does the European Society classify polyps hysteroscopically?
Type 0 - fibroid polyp
Type 1 - Less than 50% within the myometrium
Type 2 - More than 50% in the myometrium.
List 4 uterine malformations.
1) Arcuate uterus
2) Bicornuate nucleus
3) Uterine septum
4) Unicornuate uterus
What determines the difference between an arcuate nucleus and a uterine septum?
The depth of uterine muscle in the midline of the cavity indicates the degree of uterine septum or arcuate uterus.
What is an arcuate uterus?
A mildly variant shape of the uterus. It is technically one of the Müllerian duct anomalies, but is often classified as a normal variant. Least associated with reproductive failure.
What is a uni/bicornate nucleus?
When a uterus has one of two horns.
What is a uterine septum?
A uterine septum is an upside-down, triangular shaped piece of tissue which divides all or part of the uterine cavity in two. The tissue is a left over remnant from normal, embryonic uterine development.
What does a "Bagel sign," indicate?
The presence of an ectopic pregnancy.
How are ectopic pregnancies treated?
83% successfully with methotrexate.
- Single dose
- Multiple dose
(1 case treated with intra-amniotic KCl) Kirk et al 2004.
What are the indications of surgically managing an ectopic pregnancy?
- Haemodynamically unstable
- High hCG
- Viable ectopic pregnancy
- Large ectopic mass
How and why is the endometrium measured?
- Double thickness measurement of both endometrial surfaces at thickest point in a midsagittal view.
- If fluid present, layers individual measured and summated.
Outline the study used to establish the presence of endometrial cancer.
Meta-analysis of 85 studies including 5892 women showed that an endometrial thickness of greater than 5mm identified 96% of endometrial cancers. Smith-Bindman R et al 1998.
When should a Sonohysterography be used?
When an endometrial wench is not well visualised or when it is not thin and distinct.
What does high vascularity mean in one area of the uterus?
Potential presence of cancer.
List the ovarian pathologies.
- Dermoid cysts (totipotent cells, have teeth and hair present.)
- Mucinous cyst.
-Ovarian cancer - post menopausal women. (Blood flow, acytes, tumour markers)
List the clinical applications of ultrasound.
- Assessment of Uterus and ovaries
- Assessment of uterine cavity
- Tubal patency – hycosy
- Follicle growth
- Egg retrieval
- Embryo transfer