introduction to abdominal radiology meghan woodland, dvm
TRANSCRIPT
Introduction to Abdominal Introduction to Abdominal RadiologyRadiology
Meghan Woodland, DVM
IndicationsIndications
• Vomiting/Diarrhea• Abdominal Pain• Hematuria• Abdominal Mass/Distension• Tenesmus (Pain on Defecation)
Technical FactorsTechnical Factors
• Abdomen has low inherent contrast– Lower kVp– Higher mAs
• Collimation– High amount of scatter– Use grid (if patient is >10-11cm thick)
• Take exposure on expiration
PositioningPositioning
• VD and R lateral views• Include from diaphragm to pelvic inlet• Fore limbs pulled cranially• Hind limbs pulled caudally• Additional views as necessary
Radiographic techniques: the dog
By Joe P. Morgan, John Doval, Valerie Samii
Radiographic techniques: the dog
By Joe P. Morgan, John Doval, Valerie Samii
Improper positioning. Could miss a diaphragmatic hernia.
Unprepared Abdomen
“Butt Shot” – Urethral Calculi
Interpretation of Abdominal Interpretation of Abdominal RadiographsRadiographs
• Liver• Spleen• Kidneys• GIT (Stomach, SI, Cecum, LI)• Bladder• Prostate• Extra-abdominal structures
Structures Not Normally SeenStructures Not Normally Seen
• Gall bladder• Pancreas• Adrenals• Ovaries• Uterus• Ureters• Lymph Nodes• Mesentery• Vasculature
LiverLiver
• Lateral view: – Caudo-ventral margin angular– Should not extend beyond the costal arch– Normal gastric axis parallel to ribs or perpendicular
to spine
• VD view:– Liver margins not well seen– Long axis of stomach perpendicular to spine
Over-inflation of chest gives false appearance of enlarged liver
SpleenSpleen
• Size is subjective• Lateral view:
– Tail of spleen visible, but position varies– Not usually seen on this view in cats
• VD view:– Head of the spleen is visualized
• Caudo-lateral to stomach fundus• Cranio-lateral to left kidney
– Cats : often seen lying along the left body wall
Dog – Lateral View
Dog – VD View
Cat – Lateral View
Cat – VD View
KidneysKidneys
• Right located cranial to left• May be difficult to see in young or emaciated
animals• Size (only evaluated on VD view)
– Dogs: 2 ½ to 3 ½ times the length of L2– Cats: 2 to 3 times the length of L2
Dog – Lateral View
Dog – VD View
Cat – Lateral View
Cat – VD View
Gastrointestinal TractGastrointestinal Tract
• Stomach– Caudal to liver– Gastric Axis– Less than 3 ICS wide on lateral view– VD:
• Dog = U-shaped• Cat = J-shaped
Dog – VD View
“U-Shaped” Stomach
Cat – VD View
“J-Shaped” Stomach
Gastrointestinal TractGastrointestinal Tract
• Small Intestine– Size: Width less than 3 times the last rib– Duodenum
• Fixed along the right side• Extends caudally from the pyloric region of the
stomach
– Jejunum/Ileum• Position Varies• Mid-ventral abdomen
Gastrointestinal TractGastrointestinal Tract
• Cecum– Comma shaped– Mid, right abdomen– Not often seen in cats
• Large Intestine– Ascending, transverse and descending colon– Size: Width less than 5 times the last rib
Cecum – VD View
Cecum – Lateral View
Megacolon in a Dog
Descending colon
Transverse Colon
Ascending Colon
Contrast Study
Transverse Colon
Ascending Colon
Descending colon
BladderBladder
• Size varies• Dog:
– Oval to ellipsoid– Caudal abdomen or pelvic
• Cat:– Ellipsoid– Always intra-abdominal (elongated bladder neck)
Dog – Lateral View
Bladder more pelvic
Cat – Lateral View
Long Bladder Neck
ProstateProstate
• Intact males ++• Caudal to bladder• Symmetrical with smooth margins• Size:
– Lateral: Less than 70% of sacro-pubic distance– VD: Less than 50% of pelvic inlet width
Extra-Abdominal StructuresExtra-Abdominal Structures
• Soft Tissues• Bone (Spine, Pelvis, Hind limbs)• Diaphragm• Thorax (if visible)
Decreased Abdominal DetailDecreased Abdominal Detail
• Inability to distinguish organs• Causes:
– Young Animals *– Emaciated Animals– Peritoneal Fluid– Inflammation (Peritonitis, Pancreatitis)– Carcinomatosis
Normal finding
Emaciated Cat
Abdominal Fluid
How Many Babies?
Fun SlidesFun Slides
Where is the foreign body?
What organs are mineralized?
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THE END!THE END!