Normal Abnormal US

Ultrasonography Dr. LeeAnn Pack Dipl. ACVR

Normal Anatomy - Liver  Size of liver – Assessed subjectively (rads are superior)

 Parenchyma – Homogenous, uniform – Interrupted only by portal & hepatic veins  Portal veins have echogenic walls  Hepatic veins = black tubes  Hepatic arteries are not seen

Normal Anatomy - Liver  Echogenicity – Dog: Spleen > liver > kidney – Cat: Spleen = liver > kidney

 Texture – More coarse texture than spleen

Normal Anatomy

Portal vein

Diaphragm

Normal

Abnormal

Vasculature  Portal veins – More echogenic than hepatic veins due to surrounding fibro-fatty tissue – Less visible with PSS, fibrosis, & cirrhosis  Hepatic veins – Best seen cranially near diaphragm (emptying into vena cava) – Walls not visible

Vasculature

Indications for US - GB       

Thickened wall Stones Mucoceles Cholestasis Cholecystitis “Sludge” Icterus

US Technique - GB  How to find it?  Anechoic, round to oval structure to right of mid-line

Normal Anatomy - GB  Wall is thin echogenic line  Size of GB is variable  Cat GB is bi-lobed

Feline Bi-lobed GB

Enhancement

Pathology - GB  Kiwi-shaped extensions – GB mucocele

 Hyperechoic areas in wall – Edema – Acute inflammation

 Large, hyperechoic sediment – Sludge vs Cholelith  Cholelith – usually cause acoustic shadowing

GB Mucocele

GB Mucocele

GB Mucocele + perf

Cholelith

Sludge in GB

Thickened GB Wall

Normal Anatomy Spleen

Splenic Hilus

Normal

Abnormal

Ultrasound Technique - Spleen  Left side of body  Head of spleen – Under border of rib cage on left

 Body & tail of spleen – Along left body wall – Ventral or lateral to left kidney

 Scan sagittal & transverse

Anatomy  Size of normal spleen variable – Assessed subjectively – Enlarged spleen may cross midline or extend caudally to the bladder

 Parenchyma – Homogenous, finely textured

 Echogenicity – Dog: Spleen > liver > kidney – Cat: Spleen = liver > kidney

Normal Spleen

Anatomy  Capsule – Smooth, regular, VERY echogenic

 Splenic veins – Only other structure normally visualized – Poorly visualized except near hilus  “Whale tail”

– Enlargement subjective

 Hilus – Check for lymphadenopathy

Splenic Hilus

Non Homogenous

Splenic Mass

Neoplasia  Lymphosarcoma – Diffuse or focal/multifocal – Hypoechoic or hyperechoic – Can appear normal

 Hematoma, hemangioma, hemangiosarcoma – Unable to differentiate – Focal – Hypoechoic, hyperechoic or mixed

Lymphosarcoma

Hemangiosarcoma

Thrombosis

Splenic Thrombus

Myelolipoma

U/S Technique - Bladder  Use high-resolution transducers (7-12 MHz)  Located very superficially  Pressing too hard distorts the image

Normal Anatomy - Bladder  Bladder wall thickness (1-2mm) – Dog: 1.6 mm – Cat: 1.7 mm

 Wall thickness changes with bladder size  Ureters & urethra not visible unless filled with urine

Pathology  Intraluminal changes – Urinary calculi – Gas bubbles – Cellular and crystalline debris – Blood clots

 Bladder wall changes – Cystitis – Neoplasia – Polyps

Urinary Calculi  Calculi very hyperechoic  Large calculi can cause acoustic shadowing  Ballotment doesn’t usually make calculi move, but standing the animal will

Urinary Calculi

Calculi

Cystic Calculi

Cystic Calculi

Debris  Variable echogenicity  Can become thick enough to form confluent layer with bladder wall  Vigorous ballotment will cause a swirling pattern – looks like snow globe

Cystitis  Chronic cystitis leads to diffuse thickening of wall  Small mucosal masses sometimes present  Muscular hypertrophy caused by chronic partial lower urinary tract obstruction  Emphysematous cystitis

Cystitis

Chronic Cystitis

Neoplasia  Single or multiple masses  Irregularly shaped, broad-based hypo or hyperechoic masses protruding into bladder lumen  Transitional cell carcinoma most common

Neoplasia

Neoplasia

Indications for U/S - Kidneys  U/S very useful for evaluating: – Size, shape, position, echogenicity

 In some cases, has replaced EU’s – Provides more info regarding morphology

 Does NOT provide information about renal function

U/S Technique - Kidneys  The left kidney is found just medial to the head of the spleen – Usually close to the body wall so start at body wall and pull transducer medial

 The right kidney resides in the renal fossa of the liver – Start at liver and proceed caudal along body wall – Can be more difficult to find and more difficult to make a “pretty image” – May be under the rib cage

Normal Anatomy - Kidney  Location – Left kidney: caudal to stomach & caudomedial to spleen – Right kidney: within caudate process of caudate lobe of liver

 Length (in sagittal plane): – Dog: depends on size & weight of the dog – Cat: 2.8-4.2 cm

 Echogenicity – Cortex hyperechoic to the medullary portion

Normal Anatomy - Kidney  The cortex and medulla should be of equal thickness and clearly defined  Capsule is slightly hyperechoic  Best to see renal pelvis on the transverse view

Normal Anatomy - Kidney

Note the Capsule

Lymphosarcoma

Renal Infarct

Polycystic Kidneys

Polycystic Kidneys

Lymphosarcoma

Interstitial Nephritis

Ethylene Glycol

Large Renal Cyst

Nephrolith

Normal Sagittal

Hydronephrosis

Hydronephrosis

Hydronephrosis

Hydroureter

Normal Transverse

Hydronephrosis