Reproductive: Ovary/Adnexa Flashcards
In general, when should you recommend biopsy of an ovary?
Basically never
Best way to find an ovary on CT if it is difficult
Follow the gonadal vein
Is hemorrhage in a cystic mass a reassuring or suspicious feature?
Reassuring (usually benign)
When should you consider an ovary enlarged?
- Larger than 15-20 mL
- Larger than 6 mL OR twice the size of the contralateral ovary (if postmenopausal)
What occurs due to the surge of luteinizing hormone during the menstrual cycle?
Ovulation
Ovarian follicle vs cyst
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
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.
What medication is used to force the maturation of multiple bilateral ovarian follicles as part of egg harvesting?
Clomiphene citrate (Clomid)
Note: Pts taking this may have many bilateral ovarian cysts.
This pt is likely taking what medication?
Clomiphene citrate (Clomid)
Note: This is used to force maturation of multiple ovarian follicles as part of egg harvesting.
Theca lutein cysts (functional cysts related to overstimulation by beta-hCG)
Note: Think ovarian hyperstimulation syndrome, multifetal pregnancy, or gestational trophoblastic disease.
Differential for theca lutein cysts
- Ovarian hyperstimulation syndrome (due to fertility therapy)
- Multifetal pregnancy
- Gestational trophoblastic disease
Ovarian hyperstimulation syndrome
Note: Theca lutein cysts (enlarged ovaries with many functional ovarian cysts), ascites, and pleural effusion.
Complications of ovarian hyperstimulation syndrome
- Ovarian torsion (due to big ovaries)
- Hypovolemic shock (due to ascites, pleural effusions, pericardial effusion)
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).
Hot ovary on PET imaging…
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.
Definition of menopause
No menses for at least 1 year
Small cyst (<3 cm) in a postmenopausal pt…
Normal (seen in ~20% of postmenopausal pts)
When should you recommend getting a pelvic ultrasound for an incidental simple-appearing ovarian cyst seen on CT?
- Larger than 3 cm (premenopausal)
- Larger than 1 cm (postmenopausal)
Note: Smaller cysts do not need an ultrasound.
When should you recommend follow up for an incidental simple ovarian cyst on ultrasound?
- Larger than 7 cm (premenopausal)
- Larger than 5 cm (postmenopausal)
Note: Follow up should be repeat ultrasound in 3 months.
What makes an ovarian cyst not simple?
- Irregular septations
- Papillary projections
- Solid elements
Note: These should prompt recommendation for gynecology consult.
At what point would you stop calling an ovarian cyst a functional cyst and start calling it a nonfunctioning cyst
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).
Corpus lute cyst
Corpus lute cyst
What features suggest a lesion with a peripheral “ring of fire” is an ectopic pregnancy rather than a corpus luteum?
- 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
Infertility, dysmenorrhea, and dyspareunia…
Think endometriosis
Endometrioma
Note: Rounded mass with homogenous low level internal echoes and increased through transmission is how 95% of endometriomas appear.
What is the most sensitive imaging feature on MRI for the diagnosis of malignant degeneration of an endometrioma?
An enhancing mural nodule
What is the most reliable way to differentiate an endometrioma from a hemorrhagic cyst?
Follow up imaging in 6-12 weeks (endometriomas will stay the same, but hemorrhagic cysts will change
What is the most common location for solid endometriosis?
The uterosacral ligaments
Do endometriomas increase risk for cancer?
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).
Risk factors for malignant transformation of an endometrioma
- Size > 6-9 cm
- Age > 45
Decidualized endometrioma
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.
What are the MRI features of an endometrioma?
- 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)
Why do endometriomas exhibit “shading” on MRI
Shading refers to signal loss on T2 relative to T1 sequences. Endometriomas do this (become darker on T2) due to their iron composition
Think hemorrhagic cyst
Note: Lacy fishnet appearance with enhanced through transmission.
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)
70 y/o F with a hemorrhagic ovarian cyst…
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).
Ovarian ultrasound
Think dermoid cyst
Note: This is the “tip of the iceberg” sign.
Dermoid cyst
Note: Hyperechoic Rokitanski nodule with posterior shadowing. Dot-dash sign of hair.
What is best MRI feature to look for when diagnosing an ovarian teratoma?
Macroscopic fat (signal loss on fat saturation imaging)
Note: Endometriomas and hemorrhagic cysts will not have macroscopic fat.
Can teratomas undergo malignant transformation?
Yes, approximately 1% do (almost always to squamous cell carcinoma)
Risk factors for malignant degeneration of an ovarian teratoma
- Large size (> 10 cm)
- Older pts (> 50 y/o)
Think ovarian dermoid cyst
Note: Lesion contains soft tissue, fat, and calcification.
Imaging criteria for polycystic ovaries
- 10 or more small, peripherally-based simple cysts
Note: Ovary is usually, but not always, enlarged (> 10 mL).
