Lecture 2 Abdomen Flashcards
Pylorus of the dog
To the right of midline
Sphincter located at the lateral aspect of the right cranial abdomen.
Pylorus of the cat
Generally on midline or slightly left of midline
On right lateral view pylorus fake out:
pylorus may look like a round soft tissue opacity or a foreign body
- compare by looking at a left lateral view
- redistribution of fluid and gas may collect in pylorus for easier id
Right lateral recumbency
Gas is in fundus
Left side of stomach is up
Left Lateral recumbency
Gas is in pylorus
right side of stomach is up
Rugae
With contrast medium
Appear as linear ‘filling defects’
Determination of normal is empirical
There are fewer rugae in the cat compared to the dog
An increase in size and/or number may indicate an abnormality
Contrast medium patterns
- Normal
* smooth margins that follow the contour of the lumen - Erosion/ulcer
* collection of contrast within a ‘pocket’ or ‘tract’ - Intramural mass
* filling defect - Intraluminal mass
* filling defect - Gastric peak sign
* pyloric hypertorphy
GDV
Take a R. lateral
- will see pylorus dorsallly with gas (normally no gas should be present)
- +/- splenomegaly
- Compartmentalization
- soft tissue bands that cross the stomach
- represents stomach folding onto itself
Cat stomach
Smaller, foreign material is common
- trichobezoar
- hairball
Fat in sub-mucosa
Foreign bodies
Penny foreign bodies can lead to zinc toxicity and anemia
Needles can be found in dogs and cats in
- stomach
- liver
- peritoneal space
Gastric masses
Most common in cats with lymphoma
- thickening of gastric wall
Chronic outflow tract obstruction
Pyloric hypertrophy
neoplasia
foreign bodies
*after vomiting stomach can look normal, all bets off for Id ing foreign body obstruction
Small intestines
- Shoudl occupy the mid abdomen, normally filled with fluid
- Duodenum is right sided structure
- Ileum enters the colon at the ileocolic junction to the right of the midline
- In a fat cat the small intestinal tract is often bunched in the right mid abdomen
- Pseudo-ulcers
- peyers patches or GALT
- can be seen along anti-mesenteric border of duodenum on US eval or on UGI
Cecum
- Generally to the right of midline on VD
- Is located in the central abdomen on lateral view
- Has a curved C-shape appearance in dogs
- Not seen in cats
Colon
- Ascending-right midline (VD)
- Transverse-Immediately caudal to stomach (Lat, VD)
- Descending-Left of midline (may be on midline or to right of midline if urinary bladder is very distended)
Ileus
Abnormal intestinal dilation
Focal/mechanical => obstruction
Generalized => functional, paralytic ileus
‘sentinal loop’
Gravel sign
- chronic, partial obstruction
Eye catching, not the actual obstruction
Intussusception
Ileocolic most common
caecal inversal
Linear foreign body
Intestinal segments not big/distended but plicated
foreign body often originates in Pylorus or duodenum
Intestinal masses
Cat
- Lymphoma
- Gas in center or eccentrically placed in soft tissue mass
- Can have gravel sign
- Differential of mast cell tumor
- Can be multi centric
* kidneys, mesenteric LN
Intestinal masses
Dogs
Adenocarcinoma most common
- lymphoma or smooth muscle tumors possible
Gravel sign and gas in mass also seen (like in cats)
Locations
- Gastric
- jejunal
Mesenteric volvulus
Twist at the root of the mesentery
Generalized severe small intestinal dilation
German Shepherds with Pancreatic Insufficiency
Can be stacked in appearance
surgical emergency
Distal Ileal Adenocarcinoma
- Adenocarcinoma creates a stricture and circumferential narrowing at the distal ileum
- Creates chronic partial obstruction
- Creates gravel sign can be confused for obstipation
- UGI will take forever
- US will miss it
radiographic dx
- Metastasis to regional lymph nodes likely
Pancreatitis
- mass effect in area of body of pancreas
* junction of right and left lobes at the pyloro-duodenal junction - dudenal ileus
- decreased detail usually focal to area of the pancreas
- sequelae to pancreatitis can included
- abscess
- pseudocyst formation
- pancreatic necrosis
- Mesenteric saponification and fat necrosis related to enzyme release in peritoneal space
