Exam #3: Kidneys, Bladder, Spleen

The kidneys are a… organ

Retroperitoneal

Where are the kidneys located?

Posterior to diaphragm

What is a kidney?

Dark red, bean-shaped organ

What is the normal length of the kidneys?

9-12 cm

What is the cortex of the kidney?

Outer portion of kidney tissue

What is the normal thickness of the cortex of the kidney?

1 cm or above

What is the medulla of the kidney?

Inner portion of kidney tissue

Which part of the kidney is folded into anechoic pyramids?

Medulla

The medulla is folded into… which empty into the…

1. Anechoic pyramids

2. Renal pelvis

What is a nephron?

Renal tubules

What is the functional unit of the kidney?

Nephron

What is the renal corpuscle?

Where blood is filtered

What is the glomerulus?

Network of capillaries

The renal tubule filtrate passes into the… from…

1. Renal tubule

2. Bowman’s capsule

What is the renal hilum?

Vertical slit on medial surface of each kidney

What does the perinephric fat cover?

Fibrous capsule

What is Gerota’s Fascia?

Renal fascia composed of areolar connective tissue

What does Gerota’s Fascia cover?

1. Perinephric fat

2. Kidneys

3. Adrenal glands

What is a ureter?

Tube that carries urine from kidney to bladder

What is the normal length for the ureter?

25 cm

What is the urinary bladder?

Large muscular structure that acts as a storage site for urine

The urinary bladder is lined with… that allows the bladder to…

1. Transitional epithelium

2. Stretch

What is the urethra?

Membranous tube from bladder to outside body

What two structures does the urethra consist of?

1. Internal sphincter

2. External sphincter

The internal sphincter of the urethra is… while the external sphincter is…

1. Involuntary (smooth muscle)

2. Voluntary (skeletal muscle)

What is the major function of the kidney?

Excretion of urine

What does excretion mean?

When body pulls metabolic waste from blood stream and disposes it

Which structures are able to maintain homeostasis via excretion?

1. Skin (sweat)

2. Lungs (CO2)

3. Liver (multiple toxins)

4. Large intestine (feces)

5. Kidneys (urine)

What is a urinalysis?

Series of lab tests performed on urine

What is a urine pH test?

Testing the pH of urine

What is a specific gravity test?

Test that measures kidney’s ability to concentrate urine

What is hematuria?

Blood cells in urine (RBCs)

When is hemoglobin found in the urine?

Extensive RBCs destruction

Is creatinine typically found in the urine?

Yes

What is indicated if there is less creatinine in urine than normal?

Glomerular apparatus malfunction

Is creatinine typically found in the blood?

No

What is indicated if there is more creatinine in blood than normal?

Renal failure

What is the normal texture of the kidney?

Smooth

What is the echogenicity of the parts of the kidney in order from most to least echogenic?

1. Renal Capsule (echogenic)

2. Renal Pelvis/Sinus (echogenic)

3. Cortex (medium-level gray)

4. Renal Pyramids (hypoechoic)

What is described as the area from renal sinus to capsule?

Renal parenchyma

The cortex is the… portion of the renal parenchyma

Outer

Right renal artery runs… to…

1. Posterior

2. IVC

Left renal vein runs… to…

1. Anterior

2. Aorta

What structures define the cortico-medullary junction?

Arcuate arteries

What structure distinguishes that a renal image taken in the trasnverse plane is at the mid-level?

Renal hilum

The left kidney is adjacent to the…

Spleen

The right kidney is adjacent to the…

Liver

What is a pelvic kidney?

When kidney moves caudally with embryo axis
as it lengthens and fails to “ascend” to lumbar
position

What is the most common location of ectopic kidneys?

Pelvis

What is a horseshoe kidney?

When right and left areas of metanephric mesoderm are located very close to each other and fuse in midline, usually at inferior pole

If fusion occurs at the mid portion of the kidney…

Cake kidney

What is renal agenisis?

When ureteric bud doesn’t come into contact
with metanephric mesoderm so there is no induction of nephron formation

What is bilateral agenesis?

Complete absence of both kidneys that is not compatible with life (lethal)

What is an ectopic ureter?

When ureteric bud develops at abnormally inferior place on mesonephric duct

What is a duplicated collecting system?

When ureteric bud splits and creates a second collecting system

What is a hypertrophied Column of Bertin?

Prominent fold of renal cortical tissue that produces down into medulla towards renal sinus

What are the defining characteristics of a hypertrophied Column of Bertin?

1. Clearly separated from renal sinus

2. Contiguous with renal cortex

3. Isoechoic to renal parenchyma

4. 3 cm or less

What is a Dromedary Hump?

Bulge of renal cortex on lateral surface of kidney due to pressure on developing fetal kidney from spleen

What are the defining characteristics of a Dromedary Hump?

1. Usually on left kidney

2. Isoechoic to renal parenchyma

What is a junctional parenchymal defect?

Triangular indention in upper pole or renal parenchyma that results in partial fusion of two embryonic ranunculi that form kidney

Where are junctional parenchymal defects typically seen?

Peripheral border of kidney

What is fetal lobulation?

Fusion of ranunculi that results in part of kidney being rotated

What is sinus lipomatosis?

Extra fat deposition in renal sinus that causes enlargement of renal sinus

What is extrarenal pelvis?

Enlargement of proximal end of ureter

Are ureters easily seen on an ultrasound?

Difficult to see unless dilated

Bladder must be… to evaluate with sonography

Full

Empty bladder will have… which make it difficult to evaluate

Thick walls

What is the normal appearance of the bladder?

1. Thin, smooth walls

2. Anechoic lumen

3. Should be located in midline

What is duplicated ureters?

Duplication of collecting system that may involve complete or partial duplication of ureter

Complete ureter duplication is seen as…

Ureters insert inferiorly on bladder

Partial ureter duplication is seen as…

Ureters fuse before reaching bladder

What is a ureterocele?

Cyst-like enlargement of distal ureter

The spleen is an… organ

Intraperitoneal

Where is the spleen located?

1. LUQ

2. Near pancreatic tail

3. Superior and lateral to left kidney

What is the largest mass of lymphoid tissue in the body?

Spleen

What is the primary function of the spleen?

Filter foreign material from blood

What is pitting?

When spleen removes nuclei from RBCs

What is culling?

When spleen filters out abnormal RBCs

What is a hematocrit?

Describes percentage of given volume of blood made up of RBCs

What is bacteremia?

Presence of bacteria in blood stream (sepsis)

What is leukocytosis?

Elevated WBC count

What is leukopenia?

Abnormally low WBC count

What is thrombocytopenia?

Lack of platelets caused by splenomegaly

What is the sonographic appearance of the spleen?

1. Similar shape to liver

2. Isoechoic to liver

3. Homogenous to liver

4. Hilar area is similar to liver and kidneys

What is the normal size of the spleen?

8-12 cm

What is the abnormal size of the spleen?

Cranio-caudal length = more than 13 cm

What is the cranio to caudal measurement?

Measure maximum dimension of spleen in long

Where is the splenic vein located?

1. Travels from splenic hilum to IVC

2. Runs along posterior border of pancreas

3. Joins MPV

What is the most common splenic congenital variant?

Accessory spleen

What is an accessory spleen?

Small round/ovoid structure of same echogenicity/texture as spleen tissue usually in splenic hilum

What is an ectopic spleen?

Spleen position is variable in abdomen/pelvic
due to laxity of splenic suspensory ligaments

What is the nickname of the ectopic spleen?

Wandering spleen

What is polysplenia?

Multiple small spleens in LUQ rather than a normal spleen

Polysplenia is associated with…

Left sided laterality sequence

What is asplenia?

Congenital absence of spleen

Asplenia is associated with…

Right sided laterality sequence