Imaging Flashcards
List some indications for using radiology in gynaecology.
Diagnosis of pelvic pain.
Assess pelvic masses
Investigate abnormal menstrual bleeding.
Assessment of patients with post-menopausal bleeding.
Investigate infertility
Interventional radiology (e.g. fallopian tube recanalisation)
What are the 2 main ultrasound techniques used?
transabdominal
transvaginal
A patient must have an empty/full bladder for a transabdominal ultrasound. Which one and why?
FULL bladder
The urine-distended bladder acts as an ‘acoustic window’; it displaces gas-filled bowel loops out of the pelvis (bowel gas scatters the ultrasound beam and degrade image quality)
What are the disadvantages of transabdominal ultrasound?
Difficult to obtain good images in obese patients and in those where there is gaseous distension of the bowel.
Operator dependent.
Difficult to produce exactly same images every time - not often used in assessing response to cancer treatment
Transvaginal scanning uses higher frequency ultrasound than transabdominal scanning.
T/F?
Implications?
TRUE
Higher frequency = shorter wavelength & better spatial resolution
BUT
more likely to be scattered in the body so the transducer needs to close to the target organ.
Transvaginal ultrasound requires an empty or full bladder?
EMPTY
Full bladder can make the examination uncomfortable.
When is CT used in gynaecology?
2nd line after USS in PC of acute abdominal pain.
Post-surgical complications (e.g. post-op abscess, small bowel herniation)
Staging of ovarian and endometrial cancers esp.
Assess response to chemo ± radiotherapy
Advantage of using MRI over CT?
no ionising radiation in MR - therefore suitable for children and women of reproductive age
Better depiction of pelvic organs
Soft tissue masses composition
Uses of MRI in gynaecology?
Cancer staging - esp. cervical cancer
Further evaluation of adnexal & uterine masses (after USS)
Evaluation of patients with sub-fertility (anatomical variations?)
MR of pituitary if suspected prolactinoma
How can endometriosis be diagnosed by MRI in certain cases?
Endometriosis deposits contain haemoglobin breakdown products and altered blood - seen on MR
Describe the appearance which would indicate endometriosis on T1 sequences.
altered blood returns high-signal on T1 - looks white.
Describe the appearance which would indicate endometriosis on T2 sequences.
altered blood returns lower signal on T2 - looks grey
When is hysterosalpingography (HSG) indicated?
Assess tubal patency in patients with infertility.
Outline of uterine cavity.
How does ovarian cancer disseminate?
peritoneal spread
What are some common abdominal features in ovarian cancer?
ascites, omental and peritoneal nodules - common.
sub-diaphragmatic deposits & deposits on surface of liver also seen.
Which type of metastases are uncommon normally but tend to be seen in patients with their disease modulated by chemo or in cancers with the BRCA1 mutation?
lymph node, lung and hepatic metastases
What is important to consider when staging cervical cancer?
Spread into the parametrium
extension into the vagina
Infiltration of adjacent oragans (rectum, ureters, bladder)
Metastases to regional lymph nodes (internal iliac and obturator)
What is the best method of establishing thickened endometrium in a post-menopausal patient with PMB?
transvaginal ultrasound
Which scan can be used to assess the degree of myometrial invasion?
MRI
Which scan is used to look for distant nodal metastases and pulmonary metastases?
CT
