Reproductive: Ovary/Adnexa

Question 1

In general, when should you recommend biopsy of an ovary?

Answer 1

Basically never

Question 2

Best way to find an ovary on CT if it is difficult

Answer 2

Follow the gonadal vein

Question 3

Is hemorrhage in a cystic mass a reassuring or suspicious feature?

Answer 3

Reassuring (usually benign)

Question 4

When should you consider an ovary enlarged?

Answer 4

• Larger than 15-20 mL
• Larger than 6 mL OR twice the size of the contralateral ovary (if postmenopausal)

Question 5

What occurs due to the surge of luteinizing hormone during the menstrual cycle?

Answer 5

Ovulation

Question 6

Ovarian follicle vs cyst

Answer 6

Less than 3 cm can be called a follicle in premenopausal pts (<1 cm = follicle, 1-3 cm = dominant follicle)

> 3 cm or anything in a postmenopausal woman are called cysts

Question 7

Answer 7

Cumulus oophorus (a collection of cells in a mature dominant follicle that protrudes into the follicular cavity)

Note: This is a normal finding that indicates ovulation is about to happen.

Question 8

What medication is used to force the maturation of multiple bilateral ovarian follicles as part of egg harvesting?

Answer 8

Clomiphene citrate (Clomid)

Note: Pts taking this may have many bilateral ovarian cysts.

Question 9

This pt is likely taking what medication?

Answer 9

Clomiphene citrate (Clomid)

Note: This is used to force maturation of multiple ovarian follicles as part of egg harvesting.

Question 10

Answer 10

Theca lutein cysts (functional cysts related to overstimulation by beta-hCG)

Note: Think ovarian hyperstimulation syndrome, multifetal pregnancy, or gestational trophoblastic disease.

Question 11

Differential for theca lutein cysts

Answer 11

• Ovarian hyperstimulation syndrome (due to fertility therapy)
• Multifetal pregnancy
• Gestational trophoblastic disease

Question 12

Answer 12

Ovarian hyperstimulation syndrome

Note: Theca lutein cysts (enlarged ovaries with many functional ovarian cysts), ascites, and pleural effusion.

Question 13

Complications of ovarian hyperstimulation syndrome

Answer 13

• Ovarian torsion (due to big ovaries)
• Hypovolemic shock (due to ascites, pleural effusions, pericardial effusion)

Question 14

Answer 14

Think paraovarian cyst

Note: These have an incredibly low rate of malignancy, so you don’t really care about them no matter how big they get (no need for follow up).

Question 15

Hot ovary on PET imaging…

Answer 15

Look at pt characteristics and timing:

Abnormal if the pt is postmenopausal

Abnormal if the PET was done at the right time (should be done during the first week of the menstrual cycle)

Note: If this was done in a premenopausal pt at a different time in the menstrual cycle, this may be a normal finding.

Question 16

Definition of menopause

Answer 16

No menses for at least 1 year

Question 17

Small cyst (<3 cm) in a postmenopausal pt…

Answer 17

Normal (seen in ~20% of postmenopausal pts)

Question 18

When should you recommend getting a pelvic ultrasound for an incidental simple-appearing ovarian cyst seen on CT?

Answer 18

• Larger than 3 cm (premenopausal)
• Larger than 1 cm (postmenopausal)

Note: Smaller cysts do not need an ultrasound.

Question 19

When should you recommend follow up for an incidental simple ovarian cyst on ultrasound?

Answer 19

• Larger than 7 cm (premenopausal)
• Larger than 5 cm (postmenopausal)

Note: Follow up should be repeat ultrasound in 3 months.

Question 20

What makes an ovarian cyst not simple?

Answer 20

• Irregular septations
• Papillary projections
• Solid elements

Note: These should prompt recommendation for gynecology consult.

Question 21

At what point would you stop calling an ovarian cyst a functional cyst and start calling it a nonfunctioning cyst

Answer 21

If the cyst persists on follow up and either stays the same or increases in size

Note: This indicated that the cyst is not under hormonal control (nonfunctioning).

Question 22

Answer 22

Corpus lute cyst

Question 23

Answer 23

Corpus lute cyst

Question 24

What features suggest a lesion with a peripheral “ring of fire” is an ectopic pregnancy rather than a corpus luteum?

Answer 24

• Moves separate from the ovary (CL are intraovarian)
• Thick echogenic rim (CL usually have a thin echogenic rim)
• RI < 0.4 or > 0.7 (specific for ectopic gestation, but not sensitive)
• Yolk sac/heart beat

Question 25

Infertility, dysmenorrhea, and dyspareunia…

Answer 25

Think endometriosis

Question 26

Answer 26

Endometrioma

Note: Rounded mass with homogenous low level internal echoes and increased through transmission is how 95% of endometriomas appear.

Question 27

What is the most sensitive imaging feature on MRI for the diagnosis of malignant degeneration of an endometrioma?

Answer 27

An enhancing mural nodule

Question 28

What is the most reliable way to differentiate an endometrioma from a hemorrhagic cyst?

Answer 28

Follow up imaging in 6-12 weeks (endometriomas will stay the same, but hemorrhagic cysts will change

Question 29

What is the most common location for solid endometriosis?

Answer 29

The uterosacral ligaments

Question 30

Do endometriomas increase risk for cancer?

Answer 30

Yes, approximately 1% of endometriomas undergo malignant transformation (usually to endometroid or clear cell carcinoma)

Note: This usually occurs in endometriomas that have grown to >9 cm (rare in endometriomas <6 cm).

Question 31

Risk factors for malignant transformation of an endometrioma

Answer 31

• Size > 6-9 cm
• Age > 45

Question 32

Decidualized endometrioma

Answer 32

A term used to describe a benign endometrioma with a solid, enhancing nodule in a pregnant pt

Note: ONLY in pregnant pts. If the pt is not pregnant, this would indicate malignant degeneration.

Question 33

What are the MRI features of an endometrioma?

Answer 33

• T1 bright (due to hemorrhage)
• No signal loss on fat sat (not a teratoma)
• T2 dark (this is the “shading” and its due to iron composition)

Question 34

Why do endometriomas exhibit “shading” on MRI

Answer 34

Shading refers to signal loss on T2 relative to T1 sequences. Endometriomas do this (become darker on T2) due to their iron composition

Question 35

Answer 35

Think hemorrhagic cyst

Note: Lacy fishnet appearance with enhanced through transmission.

Question 36

Answer 36

Right ovarian hemorrhagic cyst (T2 bright cyst with fluid-fluid level)

AND

Left ovarian endometrioma (T1 bright lesion that gets darker, “shades”, on T2 imaging)

Question 37

70 y/o F with a hemorrhagic ovarian cyst…

Answer 37

Think cancer

Note: Late postmenopausal pts should never have hemorrhagic cysts (perimenopausal/early postmenopausal can still ovulate, so you can get followup imaging for those).

Question 38

Ovarian ultrasound

Answer 38

Think dermoid cyst

Note: This is the “tip of the iceberg” sign.

Question 39

Answer 39

Dermoid cyst

Note: Hyperechoic Rokitanski nodule with posterior shadowing. Dot-dash sign of hair.

Question 40

What is best MRI feature to look for when diagnosing an ovarian teratoma?

Answer 40

Macroscopic fat (signal loss on fat saturation imaging)

Note: Endometriomas and hemorrhagic cysts will not have macroscopic fat.

Question 41

Can teratomas undergo malignant transformation?

Answer 41

Yes, approximately 1% do (almost always to squamous cell carcinoma)

Question 42

Risk factors for malignant degeneration of an ovarian teratoma

Answer 42

• Large size (> 10 cm)
• Older pts (> 50 y/o)

Question 43

Answer 43

Think ovarian dermoid cyst

Note: Lesion contains soft tissue, fat, and calcification.

Question 44

Imaging criteria for polycystic ovaries

Answer 44

• 10 or more small, peripherally-based simple cysts

Note: Ovary is usually, but not always, enlarged (> 10 mL).