Normal Anatomy (Midterm) Flashcards
Intersegmental
-definite division between borders (ex. hepatic veins)
Intrasegmental
-border between is unclear (ex. portal veins)
What should the liver measure, and where do you measure?
- 13 to 17 cm
- measure posterior/superior to anterior/inferior
What is the shape of the Lt lobe of the liver?
-flag shaped
How does the liver appear?
- echogenic
- homogenous
- smooth contour
How does the liver look compared to the spleen?
-the liver is hypoechoic to the spleen
How does the liver look compared to the kidney?
-the liver is hyperechoic or isoechoic to the kidney
What is the difference in appearance of hepatic veins and portal veins and their walls?
Hepatic Veins:
-larger and wider as they get closer to IVC
Portal Veins:
- very parallel
- look more echogenic
Vasculature of Liver
- hepatic veins
- portal veins
- hepatic arteries
What does the falciform ligament separate?
-Rt and Lt lobes
What does the ligamentum venousum separate?
-Lt lobe from caudate lobe
Which ligament divides the Lt lobe into medial and lateral?
-ligamentum teres (round ligament)
Where is the hepatoduodenal ligament?
-porta hepatis (enterance to liver)
Where is the gastrohepatic ligament?
-connects lesser curvature of stomach to the liver
What do the Rt and Lt triangular ligaments do?
-connect the liver to body wall
Bare Area
- posterior, superior aspect of liver
- direct contact with diaphragm
- only part of the liver not covered by peritoneum
Main Lobar Fissure
- roughly divides liver into Lt and Rt
- MHV and MPV run within it
- echogenic line that runs from GB to RPV
What does the LHV separate?
-Lt lateral and Lt medial lobes
What does the RHV separate?
-Rt anterior and Rt posterior lobes
What does the MHV separate?
-left and right lobes
What are the 3 lobes of the liver?
1) left
2) right
3) caudate
4) quadrate (sometimes 4)
What is the most basic way to divide the liver?
-Lt and Rt lobes
Portal Triad
- hepatic arteries
- portal veins
- bile ducts
Porta Hepatis
- proper hepatic artery
- main portal vein
- common bile duct
Gallbladder Layers
- fibrous outer layer (outer layer)
- smooth muscle layer (mid)
- mucous membrane (inner)
What is the best imaging modality for the biliary system?
-ultrasound
What should the CBD measure?
-less than 7mm
Couinaud’s Segments
- universal description for hepatic lesion localization
- based on portal segments
- functional and pathological importance
- each segment has: blood supply, lymphatic and biliary drainage
- 8 segments
Which segment is the left lateral superior?
2
Which segment is the Lt lateral inferior?
3
Which segment is the Lt medial superior?
4A
Which segment is the Lt medial inferior?
4B
Which segment is the Rt anterior superior?
8
Which segment is the Rt anterior inferior?
5
Which segment is the Rt posterior superior?
7
Which segment is the Rt posterior inferior?
6
Which segment is the caudate lobe?
1
Function of the Liver
- detoxification
- metabolic break down
- remove old blood cells
- recycle iron
- secrete bile (approx. 1/2 pint per day)
- stores substances (vitamin A, vitamin B12, vitamin D and iron)
- production of plasma proteins
- hematopoiesis (in fetal life)
Which 3 cells is the liver composed of?
- functioning hepatocytes
- kupffer cells
- biliary epithelial cells
Functioning Hepatocytes
- detoxification
- form bile (aids in digestion of fats)
Kupffer Cells
- also found in spleen
- immunity
- protect hepatocytes
Biliary Epithelial Cells
-lines the biliary ducts
Dual Blood Supply of Liver
- portal veins
- hepatic arteries
Portal Veins (Hepatic Circulation)
- supply up to half the oxygen requirements (even though the portal venous system is completely oxygenated)
- provides 70 to 80% of the blood supply
- greater flow
Portal System
- transports nutrients from intestines to liver
- hepatocytes metabolize and store
- blood is filtered in the liver before it dumps into systemic circulation
Hepatic Arteries
- accompany PV’s
- very small compared to PV’s
- not well seen in US
- 20 to 30% of liver’s blood supply
- provide oxygen to the liver
Ducts
- carry bile (helps with digestion)
- very small within the liver (sometimes seen along PV’s)
- bile is brought by these ducts to the duodenum to help digest food
Location of GB
- intraperitoneal
- lies within ‘GB fossa’
- RUQ
- posterior inferior aspect of liver
Main Lobar Fissure
- separates Rt and Lt lobes
- extends origin of RPV and the GB fossa
- fissure seen in approx. 70% of patients
- landmark for GB fossa
What parts is the GB divided into?
- fundus
- body
- neck
How does the GB connect to the biliary system?
-cystic duct
Which 2 ducts join to form the CBD?
- cystic duct
- common hepatic duct
Cystic duct
- contains valves of Heister (mucosal folds that prevent it from collapsing)
- extrahepatic
Bile
- secreted by liver
- stored and concentrated by GB
- aids in digestion, especially breaking down fat
- biliary tree excretes bile into duodenum
What happens to the GB after eating?
-contracts and the bile travels via ducts to the duodenum
Which hormones stimulate the biliary tree to contract?
- CCK
- secretin
GB Function
- able to expand
- acts as a reservoir
- squeezes out contents on demand
What is the normal size of the GB?
-less than 4cm transverse
What is the normal wall thickness of the GB?
-less than 3mm
What is the echogenicity of the GB?
- lumen is anechoic
- walls are hyperechoic or echogenic
What is the contour of the GB?
-smooth
What is the sonographic appearance of the GB in sagittal?
- anechoic, pear shaped structure
- echogenic walls
- in SAG should see whole length (neck, body, fundus)
What is the sonographic appearance of the GB in TRV?
- round/oval anechoic structure
- echogenic walls
- appears similar to the AO and IVC
How will a non fasting GB appear?
- non distending
- anechoic lumen, but can contain echoes
- thicker walls
- can be mistaken for bowel or a pathology
What are typical patient positions for the GB?
- supine
- Lt lateral decubitus
Which windows are used for the liver?
- anterior (subcostal approach)
- intercostal
What may cause difficulty while scanning the GB?
- reverberation
- bowel gas
What can affect the size of the CBD?
- age
- surgery
Normal Embryology of GB
- first is intrahepatic and migrates to liver surface
- 50 to 70% covered with adventitial tissue (common area to see edema)
Intrahepatic GB
- anomaly
- if GB does not migrate
- very rare
- may pose problems for laparoscopic surgery
Torsion of GB
- anomaly
- GB fully enveloped in visceral peritoneum
- hanging from mesentery
- increased mobility
Agenisis GB
- anomaly
- rare
Ectopic Positions GB
- anomaly
- suprahepatic, suprarenal, within abdominal wall, in falciform ligament
Septate GB
- normal variant
- 2 or more intercommunicating compartments divided by thin septa
GB Duplication
- usually occurs with duplication of cystic duct
- normal variant
- 2 non communicating anechoic structures
Phrygian Cap
- normal variant in GB
- kink in fundus
- looks like smurfs hat
What is a normal variation of ducts in the GB?
-CHD/CBD is seen inferior to the HA
Are the kidneys intraperitoneal or retroperitoneal?
-retroperitoneal
Which quadrant are the kidneys located in?
-RUQ
Where does the spleen lie in relation to the Lt kidney?
-superior
Where does the liver lie in relation to the Rt kidney?
-superior and anterior
External Layers of Kidney’s
1) renal capsule (aka true capsule, fibrous capsule)
- tough fibrous capsule
2) perirenal fat (aka perinephric fat, adipose capsule, packing fat of zuckerkandl)
- surrounds capsule
3) gerota’s fascia (aka perirenal fascia, perinephric fascia)
- anchor’s the kidney’s
4) pararenal fat/body
Anterior Pararenal Space (retroperitoneum)
-fat area between the posterior peritoneum and Gerota’s fascia
What organs and vessels are in the anterior pararenal space (retroperitoneum)?
- pancreas
- descending duodenum
- ascending and descending colon
- superior mesenteric vessels
- inferior portion of CBD
Posterior Pararenal Space
-between gerota’s fascia and the posterior abdominal wall muscles
What is the the posterior pararenal space?
- iliopsoas
- QL
- posterior abdominal wall
- fat
- nerves
Perirenal Space
-separated from the pararenal space by gerota’s fascia
What is in the perirenal space?
- kidneys
- adrenal glands
- perinephric fat
- ureters
- renal vessels
- aorta and IVC
- lymph nodes
What do the pararenal and perirenal fat accommodate for?
-movement during respiration
What 2 areas is the kidney divided into?
- renal parenchyma
- central sinus
Renal Parenchyma
- cortex
- medulla
Central Sinus
- renal sinus
- renal hilum
- inner aspect
- blood vessels
- renal pelvis
- nerves
- fat
Renal Cortex
- outer portion
- superficial layer of parenchyma
Medulla
- deep layer of parenchyma
- folds into projections (renal pyramid)
- renal pyramids
- renal columns
Renal Pyramids
- cone shaped (triangular) sections in medulla parenchyma
- 8 to 18
- base of pyramids is toward the outer kidney
- apices (tip) converge toward sinus
- renal papilla at the apices
Where are the renal columns?
-between the renal pyramids
Renal Hilum
- where the ureter, renal artery and renal vein leave the kidneys
- renal sinus is continous with the hilum
Are kidneys vascular?
-highly
What is the collecting system of the kidney?
-where urine flows out and makes it’s way to the bladder, then out of the body
Parts of the Collecting System Within the Kidney
- minor calyces
- major calyces
- renal pelvis
- ureter
Kidney Contour
-smooth borders
Kidney Shape
- bean shape
- convex laterally
- concave medially
Kidney Size
- 11 cm in length
- varies with size of person and age
Parenchymal Reduction
- cortex of kidney (outer layer) decreases with age
- measure of AP thickness
Echogenicity of Kidney
- hypoechoic or isoechoic to the liver
- hypoechoic to spleen
How would you determine if you are backwards in sagittal and transverse when scanning the kidney?
-hilum would be facing laterally, instead of medially
How do I know if I am sagittal medial, lateral or longest length?
medial- can see hilum
lateral- no hilum
-sweep back and forth to find longest axis
What should a TRV kidney look like?
upper pole- cortex and sinus
mid- at hilum
lower pole- cortex and sinus
Where do the adrenal glands sit?
-medial aspect of kidneys
Where is the Rt adrenal gland located?
- between IVC and UP of kidney
- near liver
Where is the Lt adrenal gland located?
- near diaphragm
- superioposterior border of spleen
What is another name for the adrenal glands?
-suprarenal
2 Main Parts of Adrenal Glands
Cortex
- 3 layers
- endocrine tissue
- coricosteroids
Medulla
- neurosecretory tissue
- catecholamines
Function of Adrenal Glands
- regulate homeostasis
- sodium and water balance
- fight or flight response
Adrenal Gland Lab Tests
- aldosterone
- cortisol
Why don’t we routinely image the adrenal glands in adults?
-difficult to visualize (small)
Why is it important to know the location of the adrenal glands?
-abnormalities can be detected with US
What do the adrenal glands look like on US in adults?
-thin hypoechoic layers, separated by hyperechoic layers
What do adrenal glands look like on paediatric patients?
- larger
- well visualized
- pyramid shape
Renal Functions
1) urine formation
- #1 function
- excrete metabolic waste from blood in the form of urine
2) homeostasis
- regulates water/salt and acid/base balance
3) endocrine gland
- secretes hormones
Basic Functional Unit of the Kidney’s
- nephron
- approx. 1 million (microscopic)
- filter blood
- in the cortex and medulla
Cortical Nephron
- in cortex
- shorter loop of henle
Juxtamedullary Nephrons
- in medulla
- longer loops of henle
What is the renal corpuscle also known as?
- glomerulus
- bowman’s capsule
Where is the loop of henle located?
-medulla
What happens in the nephron?
Filtration: filters blood, produces urine
Tubular Reabsorption: substances needed by the body are reabsorbed into the blood
Tubular Secretion: waste products and excess water pass into collecting ducts as urine
What percentage of renal function may be lost before blood levels will be elevated on tests?
50%
Serum Creatinine
- formed in muscle in small amounts, passed into blood and excreted in urine
- increased creatinine causes a disturbance in function
BUN (blood urea nitrogen)
Urea- end product of protein metabolism (normally low)
BUN level increase = function or perfusion impared
- dehydration
- urinary tract obstructions
- mental confusion, disorientation or coma
Transient Pyelectasis
- normal
- when patient drinks a lot of water (well hydrated)
- calyces and pyramids are more anechoic and prominent
- resolve’s after patient pees
- not normal if the whole collecting system is anechoic
3 Sets of Kidney’s in Embryo
1) pronephros
2) mesonephros
3) metanephros
Pronephroi
- early in 4th week gestation
- rudimentary and nonfunctioning
Mesonephroi
- late in 4th week
- function as interim kidney’s
Metanephroi
-permanent kidneys
What do the metanephroi (permanent kidney’s develop from)?
- ureteric bud
- metanephrogenic blastema
Ureteric Bud
- ureter
- renal pelvis
- calices
- collecting ducts
-ureteric bud interacts with and penetrates the metanephrogenic blastema
Hypertrophied Column of Bertin (HCB)
- normal variant
- usually on upper and middle thirds of kidney
- renal cortex is continuous with adjacent cortex
- contain pyramids
Junctional Cortical (parenchymal) Defect
- normal variant
- located anteriorly and superiorly
- traced medially to inferiorly into renal sinus
Extrarenal Pelvis
- normal variant
- mildly dilated UPJ medial to hilum
Dromedary Hump
- normal variant
- bulge on lateral aspect of kidney
- not clinically significant
Lower Urinary System
- ureters and urethra function as a conduit’s
- bladder functions as a reservoir for urine
How long are the ureters?
-approx 25 to 30 cm
Where do the ureters course?
- inferiorly behind the parietal peritoneum
- anterior to the psoas
- crosses iliac vessels anterior to the SI joint
- enters inferior bladder
What are the layers of the ureters?
- inner mucosal layer
- medial layer of longitudinal and circular smooth muscle
- outer fibrous layer
Function of Ureters
-transorts urine to bladder by urethral peristalsis
Proximal Ureter
- leaves kidney
- UPJ (ureteropelvic junction)
Distal Ureter
- enters bladder
- UVJ (ureterovesicle junction)
Where is the bladder located?
- pelvic cavity
- retroperitoneal
- female: anterior to vagina, superior to uterus
- male: superior to prostate
Bladder Wall
- smooth muscle
- inner layer forms folds (rugae)
Trigone
- ureters (corners)
- urethral opening (anterior, lower corner)
Function of the Bladder
- reservoir for urine
- expels urine from the body (aided by urehra)
Bladder Volume (cc) =
(L x W x H) x 0.523
How is the bladder measured?
SAG: long axis, diagonally
TRV: measure AP (height) and Rt to Lt (width)
-prevoid and postvoid volume
What does colour doppler help with when scanning the bladder?
- shows ureter jets at the UVJ
- aids in proving no obstruction
What happens when the bladder grows?
- distal mesonephric ducts become part of the CT in trigone
- ureters open into bladder
Anomalies Related to Growth of the Urinary Tract
- hypoplasia
- fetal lobulation
- compensatory hypertrophy
Hypoplasia
- under development
- small kidneys
- reduced nephrons
Persistant Fetal Lobulation
- normally present in children until 4 to 5 years of age
- persists in some adults (51%)
- smooth indentations
Compensatory Hypertrophy
- diffuse or focal
- diffuse: contralateral nephrectomy, renal agenesis, renal hypoplasia, renal atrophy, renal displasia
- focal: area of normal tissue enlarged in diseased kidney (looks like a mass)
Anomalies Related to Ascent of Kidney
- ectopia
- crossed renal ectopia
- horseshoe kidney
Renal Ectopia
- not in normal location
- pelvis or thorax
- no symptoms
- 50% of ectopic kidneys have reduced function
Possible Complications of Renal Ectopia
- infection
- stones
- blunt trauma
Renal Ectopia US
-not within renal fossae
Crossed Renal Ectopia
- displacement of 1 kidney to the opposite side
- 2 forms: fused (85% to 90%) OR lying on 1 side without fusion
- Lt kidney going to Rt is more common
Horseshoe Kidney
- fused lower poles at midline
- cancerous tumours are more likely to appear
- no treatment necessary if no symptoms
- may need surgery if symptoms
Symptoms of Horseshoe Kidney
- abd pain
- nausea
- stones
- UTI
Horseshoe Kidney US
- lower level than normal
- bridge of renal tissue (isthmus) connecting 2 kidneys
Renal Agenesis
- failure of formation
- unilateral or bilateral
Causes of Renal Agenesis
- anomaly of urethral bud
- absense of metanephrogenic blastema
- absense of urethral bud development
- absense of interaction and penetration of the urethral buds with metanephrogenic blastema
Supernumery Kidney
- anomaly of urethral bud
- rare
- extra kidney (smaller)
- location above, below or in front of normal kidney
- can be functioning
Symptoms of Supernumery Kidney
- pain
- fever
- hypertension
- palpable abd mass
Duplex Ureter System and Uretrocele
- complete or incomplete
- unilateral or bilateral
- congenital abnormality in distal ureter
- distal ureter balloons at UVJ forming a sac like pouch
- associated with duplication of collection system
Duplex Collecting System Complications
- uretral obstruction
- reccurent UTI’s
Treatment for Duplex Collecting System
-surgery
Congenital Megaureter
- more common in males
- results in functional ureteric obstruction
- Lt ureter is more common
Retrocaval Ureter
- abnormal embryogenesis of IVC
- ureter passes behind IVC before entering the pelvis
- usually Rt
- more common in males
- symptoms: Rt flank pain and UTI
Bladder Agenesis
- very rare anomaly
- stillborn
Bladder Duplicaion
3 Types:
1) peritoneal fold
2) internal septum
3) transverse band: band of muscle that divides bladder into 2 cavities
Bladder Extrophy
- part of the bladder is present outside the body
- often inside out
- more common in males
- failure of abd wall to close during fetal development
Urachus
-remnant of the channel between the bladder and umbilicus
Uretral Diverticulum
-pocket/outpouching forms next to the urethra and connects with urethra
Renal Duplication Artifact
- result of sound beam refraction between lower portion of spleen or liver and adjacent fat
- Lt kidney of obese patients
What does renal duplication artifact sometimes look like?
- duplex collecting system
- suprarenal mass
- upper pole thickening
How can we resolve renal duplication artifact?
- change transducer position
- using deep inspiration (liver and spleen as window)
What imaging modalities are used for the urinary system?
- IVP
- nuclear medicine
- CT
- US
IVP (intravenous pyelography)
- radiographic exam
- IV admin of contrast medium
- functional and anatomical info
- shows whole urinary tract on a few films
- ideal imaging calculi
Nucelar Medicine
- admin of IV radionuclide filtered through kidneys at a specific rate and concentration
- series of films demonstrate renal perfusion and function
- disadvantage: rely on renal function, demonstrates only gross anatomy
CT of Urinary Tract
- best detail
- can differentiate between different masses
- disadvantages: expensive, limited, ionizing radiation
Location of Spleen
- LUQ
- left hypochondriac
- intraperitoneal
What is the spleen in contact with superiorly, laterally and posteriorly?
-diaphragm
What is the inferiomedial aspect of the spleen in contact with?
-stomach, Lt kidney, pancreas and splenic flexure
Where is the spleen in relation to the stomach?
-posterior
Where is the spleen in relation to the pancreas tail?
-superior and lateral
What is the spleen surrounded by?
-fibrous capsule
What is the shape of the spleen?
- ovoid
- convex superolaterally and concave inferomedially
Border’s of the Spleen
- smooth: posterior, superior and lateral
- gental indentations: medial
Hilum of Spleen
- splenic artery and vein enter and exit
- highly vascular organ
What is the spleen composed of?
- white pulp
- red pulp
Splenic Ligaments
- splenorenal ligament
- phrenicocolic ligament
- gastrosplenic ligament
**not usually seen, unless patient has ascites
Functions of Spleen
- defense (immunity)
- tissue repair
- hematopoeisis: monocytes and lymphocytes develop
- RBC and platelet destruction
- blood reservoir: pulp and sinus store blood
Can the spleen be congenitally absent?
Yes.
Can the spleen be surgically removed?
Yes.
What should you ask your patient before scanning the spleen?
- surgery
- trauma
- sickness
Size of Spleen
- eyeball
- compare to Lt kidney
- 11cm to 12cm long (8 to 13 is normal)
- 5 cm to 7cm AP
- dependant on centre and body height
Volume of Spleen
-60 to 200mL
Weight of Spleen
- less than 150 grams (80 to 300g is normal)
- decreases as we age
- smaller in women
Shape of Spleen
- convex superolaterally
- concave inferomedially
Contour of Spleen
-smooth
Echogenicity of Spleen
-hyperechoic to liver and Lt kidney
Echotexture of Spleen
-parenchyma is homogenous
Is it normal to see calcified arteries in the spleen?
- yes
- as the patient ages
What other imaging modalities can be useful for the spleen?
- CT
- MRI
Accessory Spleen
- aka splenule
- normal variant/congenital anomaly
- most common
- homogenous, isoechoic mass, similar to the spleen
- found at hilum or inferior border
Asplenia
- complete absense
- rare
- congenital abnormality
Polysplenia
-multiple sm accessory spleens
Wandering Spleen
- migrated from it’s normal location in the LUQ
- dorsal mesentery fails to fuse properly with posterior peritoneum
- lack of support ligaments
Ectopic Spleen
-out of position
How many lymph nodes do we have?
-500 to 600
Lympatics refers to…
- lymph
- lymphatic vessels
- lacteals
- lymph nodes
- spleen
- bone marrow
- thymus gland
Function of Lymphatic System
- collects and transports excess fluids and lymph from interstitial spaces back into the venous system
- absorbs fats from sm intestine and transports to liver
- stimulates lymphoid tissue and organs to produce cells that fight and dispose of foreign material (immune system)
Common Sites for Lymph Nodes
- paraaortic and paracaval (near great vessels)
- peripancreatic area
- portahepatic area
- renal hilar area
- mesenteric region
Lymph Node Appearance
- less than 1 cm
- ovoid
- cortex: hypoechoic
- hilum: hyperechoic, fatty
- AP is smaller that width or length
The prostate is posterior to…
-symphysis pubis
The prostate is anterior to…
-rectum
The prostate is inferior to…
- seminal vesicles
- bladder
How is semen transported outside?
- epididymis
- vas deferens
- join seminal vesicles
- ejaculatory ducts
- urethra
Seminal Vesicles
- 2 hollow structures
- base of bladder
- superior to prostate
- inferior to vas deferens and ureters
Prostate
- small, chestnut shaped
- base: superior part
- apex: inferior part
Ejaculatory Ducts
-join urethra approx. mid way through prostate
Prostatic Urethra is Divided into…
- proximal
- distal
Male Pelvic Ducts
-transport seminal fluid
Seminal Vesicles
-add secretions to seminal fluid
Prostate
-adds secretions to seminal fluid
Male Urethra
-conduit for semen and urine
Prostaticovesical Arteries
- from internal iliac arteries
- prostatic and inferior vesicle artery
Inferior Vesicle Artery
-supplies the base of the bladder, seminal vesicles and ureter
Prostatic Artery
- branches to capsular and urethral arteries
- supply prostate
Venous Supply of Male Pelvis
- network around sides and base of prostate
- deep dorsal penile vein draining into the internal iliac veins
2 Regions of Prostate Gland
- fibromuscular region/stroma: smaller, anterior
- glandular region: posterior
4 Zones of Prostate
- peripheral
- central
- transitional
- periurethral glandular
Peripheral Zone of Prostate
- largest
- 70% of glandular tissue
- 70% of cancers found here
- posterior, lateral and apical regions of the prostate
- resembles ‘egg cup’
Central Zone of Prostate
- 25% of prostatic glandular tissue
- 5% of cancer located in central zone
- where the vas deferens and seminal vesicles enter
Transitional Zone of Prostate
- lateral aspects of proximal urethra
- 5% of glandular tissue
- 20% of cancers
Periurethral Glandular Zone of Prostate
-tissue that lines proximal prostatic urethra
Verumontanum
-divides prostatic urethra into proximal and distal where the ejaculatory ducts meet the urethra
Clinical Indications for Scanning Male Pelvis
- problem suspected: size, cancer, feel lump during rectal exam
- increased lab values: PSA
- urinary problems: nocturne, frequency, weak stream
DRE
-digital rectal exam
PSA
- prostate specific antigen
- blood test
- glycoprotein produced exclusively by the prostate
- increase: possible prostate cancer
- higher the elevation, the more likely it’s cancer
Why is PSA not ideal?
- normal does not excuse cancer
- 20% to 40% have cancer with normal
- elevated does not definitely mean cancer
- prostate size increases, so does PSA
Serial PSA Tests
-check if levels change over time
What anatomy is assessed for a male pelvis US?
- prostate
- seminal vesicles
- bladder
What kind of US is used to better visualize the prostate?
TRUS
Why is an abd US not the best for prostate?
- limited to size, shape, weight
- not detailed
Normal Prostate Size
weight = 20g
4cm (wide) x 3cm (AP) x 3.8cm (length)
volume x 0.523 = 23.8cc
Main Reasons for a TRUS
- prostate cancer evaluation
- biopsy
- guidance of procedures
Positioning for TRUS
- Lt lateral decub
- legs together and bent up
- DRE performed prior
Frequency of TRUS probe?
-7 to 11 MHz
Inner Prostate Gland (central)
- transitional
- anterior fibromuscular stroma
- glandular tissue
- internal urethral sphincter
- hypoechoic, heterogenous
Outer Prostate Gland (peripheral)
- peripheral zone
- central zone
- uniform, homogenous texture
- hyperechoic to inner gland
Surgical Capsule
- separates inner and outer prostate glands
- not a true capsule
- not always seen in young males
Sonographic Appearance of Seminal Vesicles
- multiseptated
- hypoechoic
Sonographic Appearance of Vas Deferens
-adjacent to seminal vesicles
Benign Ductal Ectasia
- normal prostatic variant
- older men
- caused by atrophy and dilation of prostatic ducts
- single or grouped structures in peripheral zone
- 1 to 2mm diameter
Prostatic Calcifications and Corpora Amylacea
-normal variant
-older men
bright echogenic foci/clumps in prostate
Corpora Amylacea
- proteinaceous debris
- sound attenuating preventing TRUS
