DMS 102- Unit 9 Kidneys

Retroperitoneal

The kidneys are ___________ structures

Avg kidney length

9-12 cm

Average kidney TRV (width)

5 cm in dia

Gerotas fascia

AKA renal fascia, surrounds true capsule and perinephric fat

Structures the Rt Kidney comes into contact with

R adrenal, liver, duodenum, right colic flexure, small intestine

Structures Lt Kidney comes into contact with

L adrenal, spleen, stomach, pancreas, descending colon, jejunum

Psoas major, quadratus lumborum

____________ and ___________________ are muscles posterior to the kidneys

Renal pelvis

Where the major calyces drain urine, to become the ureter

Medulla

The internal portion of the kidney containing the pyramids

8, 18

There are on average anywhere between ___ - ___ pyramids in the medulla

“Milking”

Spiral muscles around the pyramids perform a ___________ action of waste products, bringing urine into the calyces

Bases, apexes

The pyramid _______ are outward, whereas the _______ are towards the calyces

Flow of urine through the urinary system

• From Nephrons

• To pyramids

• To minor calyces

• To major calyces

• To renal pelvis

• To ureters

• To bladder

• To ureter

• To outside of the body

Cortex

The nephrons are located in the _________.

Nephron

This is the functional unit of the kidney

Blood filtration to urine production

• Blood comes in through the afferent arteriole

• To efferent

• To peritubular capillaries around renal tubule

• To prox convoluted tubule (cortex)

• To loop of henle (medulla)

• To distal convoluted tubule

• To collecting duct

UPJ

Ureteropelvic junction, the exit point for urine to flow from the kidney into the ureter, where the upper end of the ureter attaches to the renal pelvis

Pelvic brim crossing

The point the ureters transition from the abdomen to the pelvis

UVJ

The ureterovesicle junction, the point where the ureter meets and enters the urinary bladder

Common urinary obstruction sites

UPJ, pelvic brim crossing, UVJ

Dilated

The sonographer won’t typically see the ureters unless they’re _________ or something is wrong

Trigone

The ureters enter the bladder posterior laterally at the __________ of the bladder

Follow

If there is ureter dilation, the sonographer should lengthen that ureter out and _________ it.

Urethra

Membranous tube that carries urine to outside of body, has internal and external sphincters

Longer, shorter

The urethra is __________ in males and _______ in females

SLIDE #13

SLIDE #14

The 2 principal functions of the urinary system

Regulation of blood composition and excretion of urine

3 processes of urine formation

Glomerular formation, tubular reabsorption, tubular secretion

Waste products excreted by the urinary system

Water, Carbon dioxide, Nitrogenous wastes like urea, uric acid, and creatinine

Urea

Nitrogen compound from protein metabolism

Uric acid

Product from breakdown of nucleic acids

Creatinine

Waste product from muscles

Symptoms of Renal Disease/Infection

Flank pain, hematuria, Polyuria, Oliguria, fever, urgency, weightloss, generalized edema, uremia

Polyuria

Excessive urine output

Oliguria

Low urine output

Uremia

Excessive waste products that are supposed to be excreted present in the blood

Urinalysis

Testing that analyzes a urine sample’s physical, chemical, and microscopic characteristics through various forms of testing

Urine pH

Important testing for bacteria in the urine

Increased pH

This indicates more acidic urine

Decreased pH

This indicates more alkaline or less acidic urine

USG (urine specific gravity)

Analyzes the kidneys ability to concentrate urine

Low USG

_____ ____ could indicate renal failure, glomerular nephritis, or pyelonephritis (infection)

Gross hematuria

Blood seen physically in urine, not microscopic

Microscopic hematuria

Blood in urine only ID’d by microscope

Hematocrit

Lab test showing plasma to RBC ratio in the blood

Decreased hematocrit

Indicates that there is potential hemorrhage or bleeding somewhere

Hemoglobin in urine

Presence of free hemoglobin from broken down RBCs in urine

Decreased hemaglobin

Indicates extensive damage or destruction of functioning erythrocytes (breaking down rapidly within the bloodstream), injuring the kidney, may cause acute renal failure

Proteinuria or Albuminurea

Excessive protein in urine (albumin), damage to function of the kidneys

Creatinine clearance

Creatinine concentration in the urine, determines glomerular filtration rate

Decreased creatinine

Indicating renal dysfunction

Three main labs Sonographers look at

BUN, Serum creatinine, proteinuria

BUN (blood urea nitrogen)

Concentration of urea nitrogen in the blood, end product of cellular metabolism

Increased BUN

Indicates the kidneys may not be functioning correctly to carry nitrogen urea/waste products out of the body

Serum Creatinine

________ _______ is more specific and sensitive than BUN in determining renal impairment.

Hydronephrosis

Urine buildup in the kidneys

Echogenic

The renal sinus is highly __________ due to fatty center

Less

The medulla is ______ echogenic than the cortex

Homogenous, hypoechoic

The cortex is considered _________ in texture and ____________ compared to the liver

Perirenal

The kidney is surrounded by ____________ fat

Renal patient prep

Usually 4 hrs NPO, hydrated

Prone

Pediatric patients (NICU) may need to be in a ________ position to acquire images

Spleen, liver

The ___________ would be a landmark for the left kidney, whereas the ___________ would be a landmark for the right kidney.

2,5

The typical TRX used for kidney US on an adult will be a curved linear ___ - ___ MHz

5,7

The typical TRX used for children is a curved linear ___ - ___ MHz, may need to use a linear due to superficial depth

2

General rule of thumb, the kidneys should be within ____ cm difference in size.

Cortex

The area of the kidney that spans from the renal sinus to outer renal surface

Diseases of the parenchyma- Type 1

Accentuated cortical tissue, more echogenic than liver, looks similar to renal sinus in echogenicity

Diseases of the parenchyma- Type 2 changes

Distortion of normal anatomy, focal or diffuse

Segmental arteries

Branches of the main renal artery, supply the kidneys

Interlobar arteries

Arteries that course between the pyramids, branches from the segmental arteries

Arcuate arteries

Arteries on the outermost portion of the liver, close to the bases of the pyramids

Right renal artery

This structure lies extends from lateral AO to hilum of the kidney, lies around 10:00 position, posterior to IVC

Longer

The right renal artery is ________ than the left renal artery

Left renal artery

This structure extends from the posterolateral AO to hilum of the kidney, lies around 4:00 position

Right renal vein

This structure extends from renal sinus to IVC

Longer

The left renal vein is ________ than the right renal vein.

Left renal vein

Structure that extends from renal sinus, anterior to AO runs posterior to SMA to join IVC

Crura of Diaphragm

Looks incredibly similar to renal vessels, can be identified by no pulsatility and will NOT have color with Doppler

Column of Berlin

Extra cortical tissue between pyramids, continuous with the cortex with same echogenicity

Dromedary Hump

Bulge along lateral border of the liver, identical echogenicity to cortex, more common in left kidney

Junctional parenchyma defect

Triangular indent in the upper pole anteriorly, echogenic

Lobular dysmorphism

Kidney appearing lobulated, bumpy border

Fetal lobulations

Fusion of two embryonic parenchymatous masses, bumpy borders, lobulated appearance

Sinus lipomatosis

Abundant fibrofatty tissue in renal sinus, enlargement of sinus region, increased echogenicity

Extrarenal pelvis

Larger pelvis extending medially from confines of renal tissue, continuity with sinus

Renal artery, renal vein

The Sonographer should Doppler an extrarenal pelvis to prove it is not the _________ or __________.

Agenesis

Failure of a kidney to form, can be unilateral or bilateral

Dysgenesis

Defective embryonic development of kidney

Supernumerary

Complete duplication of renal system, will have 2 separate portions (sinus and cortex) and 2 jets

Pseudotumor

Overgrowth of cortical tissue mistaken for mass

Opposite, pelvis

If sonographer cannot find a kidney, it is imperative they check the _________ side and in the ________. Take images of where you looked as well.

Enlarged

If one kidney is absent or not functioning well, the other kidney may appear ___________ as it compensates.

Bifid renal pelvis

Duplication of renal pelvis with 1 ureter

Complete duplex collecting system

Confirmed ureteral jets on the same side of the bladder

Ectopic kidney

Kidney not in renal fossa, associated with vesicoureteral reflux (urine refluxing from bladder back into kidneys) and abnormal extrarenal pelvis