Ch 45 Uterus, Ovaries, and Testes Flashcards
How do you confirm fetal viability in ultrasound?
Doppler
How is the uterus differentiated from intestine?
Location and lack of distinct wall layering
The uterine wall is always the same thickness - T or F?
False, it depends on the stage of the estrus cycle.
The uterine lumen is not typically seen - T or F?
Depends; typically no, and if it is present then it will a hyperechoic central area representing mucus, except in proestrus and estrus when a small amount of anechoic fluid can be present.
In which stage of the estrus cycle is the uterine wall the thinnest?
anestrus - there is also no fluid present normally in this stage.
In which stage(s) can fluid be present in the uterus, normally?
estrus, proestrus
transiently following mating
During which estrus stage(s) is the endometrium slightly thickened?
estrus, proestrus
During which estrus stage(s) is the endometrium the thickest?
Diestrus
Why is the endometrium the thickest during diestrus?
progesterone, it causes glandular hyperplasia
What is the earliest that US can detect pregnancy in a queen?
15-17 days gestation - this is when the chorionic vesicle becomes visible
What is the earliest that US can detect pregnancy in a bitch?
18-20 days gestation - this is when the chorionic vesicle becomes visible
When can cardiac motion of a canine/feline fetus be detected on US?
after 23 days
What is the normal gestation length in dogs/cats?
63-66 days
Which method / calculation gives an 85-86% accuracy (of parturition with 2 days of estimation) in dogs?
BP (biparietal) diameter
ICC (inner chorionic cavity) diameter
What is the accuracy rate in queens for BP and ICC measurements?
Reasonably good at ± 2 days, BP slightly better
ICC 65% (± 1 day), 85% (± 2 days)
BP 73.9% (± 1 day), 91.3% (± 2 days)
- a) 15 to 17 days
- b) 18 to 20 days
d) 63 to 66 days
c) Inner chorionic cavity diameter
c) 23 to 25 days
d) 43 days
When does fetal mineralization occur in the cat, making radiographic diagnosis of pregnancy possible?
a) 32 days
b) 38 days
c) 48 days
d) 50 days
b) 38 days
What sonographic feature indicates fetal age around day 35 in the dog?
a) Cardiac motion
b) Mineralisation of the skeleton
c) Limb buds and echogenic fetal skeleton
d) Visible uterus
c) Limb buds and echogenic fetal skeleton
Why might an estimate of litter size in early pregnancy be inaccurate?
It may be an overestimation, since fetal resorption is relatively common.
What is the spalding sign?
overlapping of fetal cranial bones, it is a sign of fetal demise/death
Radiographic signs of fetal demise
- gas within or around the fetus
- spalding sign (overlapping of cranial bones)
- tightly curled fetus
- collapse of the skeleton
It can be helpful to compare to other littermates; if there is delayed development of one, it is an indication of demise.
Sonographic signs of fetal demise
loss of heartbeat
early embryonic resorption: echogenic particles within the yolk sac, progressive loss of fluid volume, hypoechogenicity of adjacent uterus
Fetal demise in a cat. There is gas around the fetus and overlap of the skull bones (white arrow).
Close-up of the skull and area of bone overlap (white arrows).
Dystocia in a dog due to a single fetus that has grown to a size that cannot pass through the pelvic canal
Dystocia in a dog due to a fetus presenting transversely
Which cause of dystocia cannot be diagnosed radiographically?
uterine inertia
What are the main causes of feto-maternal disproportion?
- If the dog is mated with a much larger breed
- if a single fetus remains/exists
- brachys, when head is large and pelvis flat
what other anomaly is common in association with uterine anomalies?
renal agenesis
why and when does cystic endometrial hyperplasia occur?
it’s the result of an abnormal response of the endometrium to progesterone that is secreted during the luteal phase (diestrus)
How long is each stage of the estrus cycle?
pyometra
cystic endometrial hyperplasia
uterus
cystic endometrial hyperplasia
uterine horn
pyometra; dependent material (pus)
uterine abscess from retained swab after c-section
What is the most common and second most common uterine neoplasia in dogs?
Leiomyomas
Leiomyosarcomas are much rarer
What is the most common and second most common uterine neoplasia in cats?
Adenocarcinoma
If there is unilateral uterine distension, what are the differentials?
neoplasia, polyps, but also pyometra (unilateral is possible)
With what conditions is uterine torsion associated?
pyometra
hematometra
endometrial polyps
What is the prognosis of uterine torsion?
poor; high fatality rate due to peritonitis and endotoxemia
what kind of contrast medium is used for retrograde vaginography?
iodinated (150-200 mg I/mL
- What condition is NOT associated with uterine torsion?
a. Pyometra
b. Hydrometra
c. Hematometra
d. Endometrial polyps
b. Hydrometra
Where should the tip of the catheter be, during a retrograde vaginogram?
within the VESTIBULE, not vagina (risk of rupture) - because if the tip is in the vagina, then the balloon will be in the orifice between vagina and vestibule (the cingulum), and then administration of contrast can result in rupture
How much contrast for a vaginogram?
approx. 1 ml/kg
Normal vaginogram; When the vagina and vestibular are maximally disternded, contrast will fill the urethra.
Vg - vagina
U - urethra
Vb - vestibule
F - Foley
What is the cingulum?
Normal narrowing between the vestibule and vagina
If a vaginogram is performed during estrus, what would you expect to happen with contrast?
It may pass into the uterus.
What are the most common vaginal tumours in dogs?
Leiomyomas and fibromas
Vaginal polyps are common in older dogs, occurring in the late part of the estrous cycle.
What should be a suspicion if a malignant neoplasia is observed in the vagina?
That it is urethral in origin; Urethral neoplasia is usually malignant and may extend into the vagina/vestibule. Vaginal tumours are usually benign.
Vaginal prolapse is seen mostly in ___________ during ________.
- young, intact, large-breed dogs
- proestrus or estrus , or near/after parturition
A mass lesion in the vagina/vestibula in a young dog might represent ________ and in an old dog, ___________.
edema, prolapse
neoplasia
ovary - normal or abnormal? what phase?
normal anestrus; hypoechoic and homogenous without visible follicles.
cat with small mineralized suture granulomas at the site of ligation of the ovarian pedicles following an ovariohysterectomy.
- In which estrus cycle phase do follicles form?
a. Proestrus
b. Estrus
c. Diestrus
d. anestrus
a. Proestrus
In which phase of the cycle are ovaries identified more easily?
Proestrus and estrus
What is the normal size of ovarian follicles?
4-6mm, with a wall <1mm
Ovarian follicles are initially too small to see, but they grow until the time of ovulation. When are they first seen?
1-3 days before ovulation
How many ovarian follicles are usually seen?
3-5
What happens to the follicles after ovulation i.e. what is the appearance?
They are replaced by slightly hypoechoic areas, which likely represent a combination of haemorrhage and follicular fluid
Newly formed corpora lutea and follicles have distinct appearances = T or F?
False, their appearance is very similar, and B-mode US alone cannot determine whether ovulation has occurred.
How would Doppler US help determine whether ovulation has occurred in a dog?
Daily monitoring of the proestrus ovary > detecting increases in blood flow, which would correlate with ovulation
ovarian carcinoma, contains severeal hypoechoic fluid-filled regions
ovary
granulosa cell tumour, it is more homogenous in appearance usually (than a carcinoma)
Which type(s) of tumor account for 40-50% of canine ovarian tumours?
papillary adenomas and adenocarcinomas
Papillary adenomas and adenocarcinomas account for ___% of canine ovarian tumours?
40-50
