Abdominal ultrasound

Question 1

Scanning stomach

Answer 1

Cranial abdomen: starting from the left side and goind through the midline to the right side: fundus–> body–> pyloric antrum–> pylorus. Pylorus has thicker wall and narrower lumen. Pylorus ‘bends’ and continues as a duodenum which has typical layered wall appearance.

Question 2

Stomach- differences between position in cats and dogs.

Answer 2

In dogs stomach goes through the midline and pylorus is located more on the right side of the body wall, moreover it bents more ‘acutely’ into duodenum.
Cats- barely crossess the midline, oblique, ‘lighter’ bent into duodenum.

Question 3

Stomach wall thickness on US

Answer 3

Ca: 3-5mm
FE: 2mm (intrarugae) up to 4.4 mm rugae.

Question 4

Stomach: perystalsis

Answer 4

5 contractions/min

Question 5

Differences in stomach wall appearance between Ca and Fe.

Answer 5

Cats have more prominent, hyperechoic submucosal layer due to fat accumulation.

Question 6

Scanning Gastrointestinal tract

Answer 6

Duodenum- Jejunum- Ileum-Colon

Question 7

Duodenum appearance on US

Answer 7

Thickest part of the intestines. 5mm Ca and 2-4 mm in cats.

Question 8

Duodenal papilla in cats.

Answer 8

2.9-5.5mm and max 4mm thick on transverse, it is common opening for bile duct and pancreatic duct.

Question 9

Duodenal papilla in dogs.

Answer 9

Separate opening of bile duct and pancreatic duct, smaller than Fe.

Question 10

Intestines- thickness

Answer 10

2-3mm in Ca and Fe

Question 11

Ileum in Fe

Answer 11

thicker than jejunum 2.5-3.2mm; wagon wheel appearance.

Question 12

Colon on ultrasound.

Answer 12

Ascending, transverse, descending.
Thickness 1-2mm Ca 1.5-2mm Fe.
No layering, strong echo/reverberations. No contractions.

Question 13

Liver lobulation.

Answer 13

From left to right: left lateral, left medial, quadrate, right medial, right lateral, caudate (papillary and caudate processes).

Question 14

Location of the Gall bladder.

Answer 14

Closeto the midline, cranial abdomen, between quadrate and right medial lobes.

Question 15

Assessing liver size on US.

Answer 15

Xrays are more useful. US: distance between diaphragm and stomach (increased/decreased); extending behind the stomach; appearance of edges (sharp/rounded)

Question 16

Liver vasculature

Answer 16

Hepatic veins- coming from every lobe and joining CVC in the very cranial part next to the diaphragm.
CVC deeper (dorsal ) to PV but ventral to AO if visible.
Portal veins- hyperechoic walls. All appear hyper if transverse.

Question 17

Liver echogenicity. Comparisons.

Answer 17

Hypo to falciform fat, hypo to spleen, similar to R kidney. Cats- more hyper.

Question 18

Assessing GB and billiary tree

Answer 18

GB between R medial and quadrate. Volume is 1ml/kg after 12h of fasting. Different amount of sludge- pathologic? Wall thickness Ca=1-2mm Fe less than 1mm.
Common bile duct- better visible in cats, immediately dorsal to PV and less than 4mm

Question 19

Pancreas- location.

Landmarks.

Answer 19

Passes cranial abdomen in transverse. Divided into left lobe, body and right lobe.
1. Left lobe is located between greater curvature of the stomach and tranverse colo, also cranially to the head of the spleen, splenic vein being an useful landmark aswell.
2. Pancreatic body- mid-cranilly ventral to the PV>
3. Right lobe- alongside descending duodenum and between right kidney.
Pancreaticoduodenal vein and pancreatic duct may help in visualisation of that organ.

Question 20

Pancreas dogs vs cats.

Answer 20

Dogs- right lobe better visualised. Less consistently visible pancreatic duct separate opening of the pancreatic duct in the duodenum (minor papilla). Thickness 4mm-10mm.

Cats: left lobe easier to localise. Bigger common major papilla as a common opening of the pancreatic duct and common bile duct. Pancreatic duct more visible: 0.5-2.5mm in size, getting bigger in older cats. Thickness L lobe: 5-9mm; R lobe: 3-6mm

Question 21

Abdominal vasculature: branches of aorta from caudal to cranial.

Answer 21

Medial sacral, internal iliac, external iliac, deep circumflex iliac, caudal mesenteric-> left colic and cranial rectal; ovarian arteries; renal aa; phrenicoabdominal aa; cranial mesenteric–> ileocolic, right colic; middle colic; caudal pancreaticoduodenal; jejunal;
Coeliac-> 1. splenic–> left gastroepiploic 2. hepatic-> hepatic branches; gastroduodenal; R gastroepiploic; cranial pancreaticoduodenal.

Question 22

Branches of cranial mesenteric arterty

Answer 22

ileocolic, right colic, middle colic; caudal pancreaticoduodenal, jejunal aa

Question 23

Branches of coeliac artery

Answer 23

Two main 1. splenic 2. hepatic

1. splenic gives left gastroepiploic