Imaging in Gynaecology Flashcards
Why should a brief assessment of the upper abdoment with transabdominal US be carried out first?
ensure no hydronephrosis (back up from gynae mass blocking ureters); detect early ascites (ovarian cancer); pelvic abnormality isnt secondary to upper abdo pathology
Why should a patient have a full bladder for a transabdominal US?
distended bladder displaces gas-filled bowel loops out of pelvis
What effect does bowel gas have on ultrasound?
scatters the beam and degrades image quality
Why is ultrasound not used for assessing response to cancer treatment?
difficult to reproduce images
What is the difference between a transabdmonial ultrasound and transvaginal?
transvaginal has higher frequency and shorter wavelength and better spatial resolution than transabdominal
What is the problem with higher frequency US?
more likely to be scattered in the body and so transducer has to be close to target organ
Why should patients have an empty bladder for transvaginal scanning?
full bladder can amke the examination uncomfrtablt
When is CT used in gynae?
second-line for US; assess post-op complications; staging malignancy; response to cancer treatment
What cancers is CT esepcially used in the staging of?
ovarian and endometrial cancers
What is the disadvantage of CT compared to MR in gynae?
MR is better at providing good tissue resolution
What imaging should be used for detail of lung parenchyma?
CT
What type of cancer is MRI used for staging?
cervical
How is endometriosis diagnosed on MRI?
endometriosis deposits conatina latered blood and haemoglobin degradation products which can show characterisitc changes of MR
What other name are dermoid cysts known as?
ovarina teratoma
What tissue is commonly foudn in dermoid cysts?
fat
Why are dermoid cysts hard to diagnose on US?
fat can be difficult to perceive on US
What is the prupsoe of hysterosalpingogrpahy?
assessment of tubal patency in patients with infertility
How is HSG carried out?
cervix is cannulated nad radiopaque contrast instilled to fill the uterine cavity
What should be done before contrast is injected in HSG?
control film obtained
How does ovarian cancer spread?
peritoneal
What is it important to determine in cervical cancer staging?
spread into parametrium; extension into vagina; infiltration of adjacent organs; mets to regional nodes
What nodes would be looked at for cervical cancer?
internal iliac and obturator nodes
What is the best method for determining abnormally thickened endometrium wtih PMB?
TVUSS
