Kristin JoudreyJune 28, 2010

Radiographic and U/S techniques Ovaries

◦ Cystic Ovaries◦ Ovarian Tumors

Uterus◦ Pregnancies

Fetal development Dystocia

◦ Pyometra

Not seen on rads! Location: Caudal to respective kidneys U/S:

◦ 1.5cm x 0.7cm x 0.5cm◦ Homogeneous parenchyma◦ Cortex-contained follicles◦ Indications

Monitoring the estrus cycle Reproductive disorders (cysts, tumors)

Cause: prolonged secretion of estrogen and attractiveness to males◦ Prolonged Estrus +/- Proestrus◦ Ovulation may not occur- abnormal estrous cycle

#1 DDx: Ovarian granulosa cell tumor

Tx: ◦ OHE◦ Further diagnostics: Vaginal cytology (cornified

cells?)

Anechoic Well demarcated Round to irregular structure

Varying echogenicity Well demarcated from surrounding tissue +/- compromised internal architecture Uni or Bilateral Generally, are rare

Transverse image of Ovarian adenocarcinoma (R ovary), ventral and caudal to kidney.

http://www3.interscience.wiley.com/cgi-bin/fulltext/119132682/PDFSTART

Not visualized on rads!

Location: between descending colon and urinary bladder

Various size ranges:◦ Cervix: 1.5-2.2cm x 0.8cm◦ Uterine horns: 10-14cm x 0.5-1.0cm◦ Uterine body: 1.4-3cm x 3cm

U/S: Homogenous, soft tissue opacity, relatively hypoechoic

Why perform survey radiology?

◦ Confirming an enlarged uterus

◦ Fetal skeletons

◦ Monitor progression of uterine size (pregnancy, disease)

◦ Fetal viability

1.Withold the food for 24 hours

2.Evacuate the colon (enema) atleast 2 hours in advance

3.Proper technique!!

4.Abdominal compression (“spoon”) test

Indications:

◦ Pelvic/vaginal mass

◦ Dysuria

◦ Hematuria

◦ Incontinence

◦ Urethral stricture

◦ Urethral tumor

Courtesy of Dr. R. Lofstedt

1.Do under G/A, lateral view 2.Water soluble organic iodide contrast media 3.Balloon-tipped catheter

◦ Insert into vestibule◦ Inflate to occlude outflow of contrast (may need to

clamp lips of vulva – do not leave clamps on longer than 15 minutes)

4.Use 10-15 mL (dogs) or 5-10mL (cats) or as needed to distend

5.Take rads when injecting last 2-3 mL 6.Filling: Vagina first, urethra, bladder

When positioning, pull the limbs forward: You don’t want the femurs superimposing over the urethra!

Courtesy of Dr. Pack

Radiographic findings:◦ Coiled tubular structure extending caudally into the pelvic canal

◦ Cranial and dorsal displacement of SI and colon

◦ Body betw. colon and bladder

Q: What are the 3 main differentials?

A:◦ Pregnancy◦ The ‘metras’◦ Gravid/Post-partum uterus

Radiographs◦ Day 42-45:

Fetal skeleton becomes opaque (mineralization) 

◦ 50+ days: Fetus count, estimate size and position of fetuses

◦ Bones become visible at different times  The mandible is the last bone to mineralize

Ultrasound:◦ Most accurate

◦ 17-20 days: Gestational sacs (blastocysts) Anechoic with hyperechoic contained areas Confirms pregnancy 

◦ 23-25+ days: Fetal heartbeat  

◦ 34-36 days: Fetal movement

(Yeager et. al. AJVR 53, 1992)

Canine pregnancy at 25 days:

Canine pregnancy at 30 days:

Click on the video!

1. Collapse of fetal skull bones

2. Intra- or peri- fetal gas accumulation  

3. Abnormal fetal posture such as increased extension of the fetal limbs

1) History of previous dystocia 2) Total parturition time >24 hr after a drop

in rectal temp. to 37.7°C 3) Abdominal contractions>1-2h 4) Active labor lasting for >1-2h 5) Resting period during active labor >4-6

hr 6) Bitch or queen in obvious pain 7) Abnormal vulvar discharge

Radiographs: Good for assessing…

Size relationship between fetus and maternal pelvic canal.

Fetal positioning relative to maternal pelvic canal

Need for C-section Retained fetus

After the onset of 2nd stage (uterine and abdominal contractions)…◦ >3-4 hours: 1st pup◦ >30min-1h (2-3h can be acceptable): subsequent pups◦ Avg completion of 2nd stage: 6hs

*Remember when doing preg checks:

◦ Stenosis of pelvic canal?◦ Check for old pelvic fractures!◦ Assess fetal viability

The ‘-metras’ are usually well visualized on U/S◦ lumen contains lots of fluid

Echogenicity of uterine contents ranges: anechoic, “textured” or hyperechoic◦ “sprinkles”

# of cells in the lumen will not always correlate with a certain echogenicity