Imaging in Obs

Question 1

Imaging methods?

Answer 1

• USG: v. important in Gynae pts
• CT
• MRI
• X-ray fluoroscopy (Hysterosalpingograms)
• PET-CT

Question 2

Indications for using radiology?

Answer 2

• pelvic pain (chronic/acut)
• pelvic masses
• abnormal menstrual bleeding
• post-menopausal bleeding )check for endometrial thickness)
• invx of infertility (hysterosalpingograms—patency of tubes)
• interventional radiology - fallopian tube (uterine art. embolisation/ fallopian tube recanalisation)

Question 3

Pros of USG?

Answer 3

• cheap
• safe (no ionising radiation)
• good def. of diff. pelvic organs
• used adjunct to pelvic exam.

Question 4

Where are medical imaging ivx stored?

Answer 4

• on PACS

Question 5

2 main USG techniques?

Answer 5

• Transabdominal
• Transvaginal (well tolerated)

—–start with the transabdominal and then transvaginal

Question 6

Why scan the upper abdomen first?

Answer 6

• ensure no hydronephrosis (better overview)
• to check for ASCITEs
• ensures pelvic abnormality is NOT secondary to upper abdom. pathology

Question 7

Why must the pt come in with a full bladder?

Answer 7

• urine-distended bladder acts as an acoustic window
• —also displaces the gas-filled BOWEL loops out of the pelvis (as the gas scatter the USG beam and degrades the quality )

Question 8

Adv. of Transabd. USG?

Answer 8

Safe
Readily available
No ionising radiation and therefore ideal for children and women of reproductive age

Question 9

Placement of the scan vertically; gives a

Answer 9

• sagittal view

Question 10

• Horizontal placement of the Transabd. USG?

Answer 10

• horizontal views of the (like Ct)..?

Question 11

Important landmark to note in transabd. USG?

Answer 11

• external iliac vessels

Question 12

Disadv. of transvaginal scan?

Answer 12

• More invasive procedure
• not for non-sexually active people
• “the tip of the iceberg”

Question 13

Normal appearance of the ovaries on the USG?

Answer 13

• FOLLICLES can be seen of the ovaries

Question 14

How does a rupture ovarian cyst appear as?

Answer 14

• mixed acougenicity

- (black and white mixing; not distinct)

Question 15

Indications of CT scan?

Answer 15

• 2nd line for acute abdomen
• to asses post-surgical complications (SBO/ adhesions/ abscesses)
• staging of gynaecological malignancies (ovarian and endometrium)
• to assess response to rx in pts after chemotherapy +/- radiotherapy

Question 16

Advs of CT?

Answer 16

Quick
The entire chest abdomen and pelvis can be assessed on one scan
Modern multiple detector row (“multislice”) scanners produce very thin slices and images can be manipulated to produce coronal and sagittal reformats, as well as the axial source images

Question 17

Disadv. of CT

Answer 17

• HIGH radiation (160 CXR)
• not used in kids and those in reproduct. age
• not optimal depiction of diff. pelvic organs

Question 18

How to confirm a dermoid cyst?

Answer 18

• dermoid cyst = FAT within cyst (black color = fat on CT)

Question 19

How diff. is T1 and T2 in picking up various substances?

Answer 19

T2- BRIGHT with water

T1- bright with proteins and blood

Question 20

Adv of MRI?

Answer 20

• safe in preg. pt except in 1st trimester
• good forkids
• excellent depiction of pelvic organs
• idea of SOFT tissue masses (contains fat/fluid/blood?)

Question 21

Disadv. of MRI?

Answer 21

• MRI not best for scanning the lungs
• TIME-consumng
• not best for those with claustrophobia
• C./I in thos with metal implants

Question 22

USe of MRI?

Answer 22

• Cancer staging
• evaluation of adnexal masses and uterine masses
• evaluation of pts with sub-fertility
• suspected prolactinoma

Question 23

How to dx endometriosis?

Answer 23

• diagnostic laproscopy

Question 24

Bright on T1?

Answer 24

• —FAT

- - BUT dark on fat-supression sequences

Question 25

Hysterosalpingography

Answer 25

• helps outline the uterine cavity
• assessment of tubal patency
• procedure done in 3-5mins
• cervix is cannulated and RADIO-OPAQUE

Question 26

Medical imaging in cancer - significance?

Answer 26

A pre-treatment scan serves as a “baseline” study so that subsequent scans can be used to assess response to treatment (chemotherapy, radiotherapy etc)

Question 27

Dx of Ovarian cancer?

Answer 27

• initial dx: made by USG

- staging by CT scanning

Question 28

Staging of cervical cancer- important to determine:

Answer 28

• spread to parametrium
• extension to VAGINA
• infil. of adjacent organs
• metastases to regional LNs

Question 29

MRI or CT for cancer scane (cervical)?

Answer 29

• MRI is good for local pathology

- CT to check for metastases

Question 30

How to check for endometrial cancer?

Answer 30

• transvaginal USG (look for THICKENED endometrium in post-menopausal women)
• —MR scan to assess degree of myometrial invasion
• –CT scanning for distant NODAL metastases and pulmonary metastases

Question 31

What should be noted with obese pts and scanning for endometrial cancer?

Answer 31

-can be large for the narrow bore of MR scanners