Spleen Flashcards
where is the spleen located?
what covers it?
what ligaments? what do they attach?
which capsule is it in?
Lt. hypochondrium
Intraperitoneal
•
Peritoneum covering entire organ, except hilum
Peritoneal ligaments
•
Attach spleen to the stomach and kidney
–
True capsule
is the hilum in direct contact w/ the peritoneum?
No
what is the avg adult size of spleen in long and AP?
12-13 cm in long, 7-8cm in AP
describe the spleens shape and texture.
which surface in convex? concave?
Variable shape: Ovid, Triangular
Smooth surface
Convex superior surface
Concave inferior surface
What surface is this?
inferior. notice the hilum
where is the spleen in relation to the pancreas? stomach? kidney?
superior and lateral to the pancreas
lateral to the stomach
anterior and slighly superior to the kidney
what ligaments extend from the spleen?
gastrosplenic ligament
lienorenal ligament
phrenicocolic ligament
Why is the spleen subject to infarction?
because of lack of anastomoses between the intra-parenchymal vessels
describe the splenic artery
from Celiac Axis
–
tortuous vessel
–
travels horizontally along superior border of pancreas
–
divides and enters the spleen at its hilum
what does the splenic vein join and form?
joins superior mesenteric vein to form the portal vein at head of pancreas
describe teh splenic vein
forms in splenic hilum
–
travels medially toward pancreatic head
–
________ also exit the spleen at the hilum
Lymph vessels
what type of pulp does the spleen have?
white and red
what are the functions of the spleen (4) as an organ of the reticulendothelial system?
production of lymphocytes and plasma cells
production of antibodies
storage of iron
storage of other metabolites
what are the functions and characteristics of the spleen (6)?
maturation of the surface of erthrocytes
reservoir
culling (keeping #s when we need them, killing excess)
pitting function
disposal of senescent or abnormal erthrocytes
functions related to platelet and leukocyte life span
what is the funciton of the spleen in the fetus?
erythropoiesis - RBC production
Splenic Protocol
–
Longitudinal with measurements in longest axis and 90o to long axis
–
Transverse with measurement in this planes longest dimension
splenic sonographic appearance
what can make it hard to visualize?
homogenous texture, smooth surface, calcifcations no uncommon
lung, stomach, gas in colon
what type of calcification are not uncommon to find in the spleen? what are they and why do they become calcified?
Granulomas-spherical mass of immune cells that forms when the body attempts to wall off substances that it perceives as foreign but is unable to eliminate. The body then places calcium around it.
what landmarks are important to find when looking for the spleen? where should you look?
diaphragm and lt kidney
posterior and superior
what are the dimensions of this spleen?
is this normal?
long 10.25cm
AP 4.22 cm
a bit small perhaps
what plane was this image taken in?
transverse
which plane are each of these spleens in? how can you tell?
lt long, rt trans
look for the hilum.
(same below)
What is it called when the spleen is larger than normal?
splenemegaly
what is the absence of the spleen called?
is it congenital?
asplenia
yes
what is polyspelenia?
is it commmon?
what else can it be associated with?
what do you need to be careful not to mistake this for when ruling out this anomaly?
multiple spleens
rare
cardiac or broncopulmonary
the lt liver lobe
what is the congenital variant called?
wandering spleen (rt line pointing to the bladder)
color example below
what is this an example of?
wandering spleen
what is one or two little spleen close to the bain spleen alled?
what can they look like?
accessory spleen (splenials, satellite spleens…)
looks exactly like the spleen and should NOT be coming of the pancreas. can be mistaken for pancreatic tail mass
which image has a pseudo-accessory spleen and which has a real accessory spleen?
what is increased number of RBC’s called?
WBC’s?
polycythemia
leukocytosis
what is a decreased number of RBC’s called?
WBC’s?
anemia
leukopenia
what is the proportion of blood volume that is occupied by red blood cells?
Hematocrit
–
what indications are may be present to cause you to do a splenic exam?
palpable spleen, abnormal labs, LUQ pain, infectious disease (mono affects spleen - making it bigger as its functioning and working hard. have to keep looking at it w/ US b/c it can burst. goes down on its own)
patient prep?
Td?
positions?
image?
compared to liver?
none
vector or curve
supline, RLD, upright
homogenous low to md level echoes.
*iso or slightly hyperechoic to live
what must you be aware of when doing a splenic exam?
Watch out for left lobe of liver.
•
Some people will have their left liver lobe right adjacent to the spleen and it can easily be mistake for part of the spleen when you are first beginning to scan.
what is the best acoustic window to image the spleen?
lt lateral intercostal approach
is the spleen found in the retroperitoneum?
no
the vascular supply feeding the spleen comes from ___. which arises from ____. this vessels characteristic feature is _____.
splenic artery, celiiac axis, torturous
the venous drainage of the spleen is via ____. it drains blood into the _____ and joins _____.
splenic vein, liver, SMV
what organ typically sits anterior to the splenic vein?
pancreas
What confluence is made by the junction of the splenic v and superior mesenteric v?
portal confluence
What specific anatomy sits directly anterior to this confluence?
pancreatic neck
If a sonographer is looking for the spleen from a lt. lateral approach , and sees the lt. kidney on the screen what direction should the probe be moved?
move more superior
What can the sonographer do to try and help visualize the tail of the pancreas if the anterior approach is blocked with gas and the pt. is unable to drink H20?
try lt lateral approach and use the spleen as an acoustic window
In relationship to the pancreatic body/tail area, where would you look for the splenic artery?
superior to the pancreas
What relationship does the lt. kidney have with the spleen, according to HA?
lt kidney is found along the medial surface of the spleen
What relationship does the splenic flexure of the colon have with the spleen, according to HA?
splenic flexure is found along the medial surface of the spleen
According to HA, what congenital variant results from an anomaly of the supporting ligaments of the spleen?
wandering spleen
What symptomatology may a patient experience when they have a wandering spleen, according to HA?
abdominal mass, pelvic mass, intermittent pain
What tool can the sonographer use to help evaluate the spleen when torsion is suspected; in a case of a wandering spleen?
color doppler to check perfusion of th espleen
what is another term for an accessory spleen?
splenule
Describe the sonographic appearance of a splenule.
round, smooth borders, homogenous and same echogenicity as the spleen
What do both of these images have in common?
splenules
These small clusters of tissue found within the normal spleen are what?
The area surrounding these clusters, making up the majority of the splenic tissue is known as what?
white pulp
red pulp
where would you put calipers to measure in long?
the following are functions of what system?
Production of lymphocytes
Production of antibodies
Storage of RBC’s
reticuloendothelial system.
isthe spleen the largest organ of the reticuloendothelial system.?
yes
Production of lymphocytes is handled by what specific portion of the splenic parenchyma?
white pulp
Ability to digest cellular debris is handle by what specific portion of the splenic parenchyma?
red pulp
Production of antibodies is handled by what specific portion of the splenic parenchyma?
white pulp
The spleen has the ability to remove old, worn out ___
RBC’s
Splenomegaly is an enlarged spleen. All of the following are causes of splenomegaly except.
A. Sequestering too many RBC’s
B. A systemic infection, such as mononucleosis
C. Renal failure
D. Portal hypertension; when PV blood can’t freely enter the liver 2o to liver disease
C
The process of destroying RBC’s which are abnormal or old is called _____.
culling
The process of fixing/removing imperfection from RBC’s without destroying them is called _____.
pitting
The spleen is of concern whenever the abdomen in involve in blunt force trauma. Why is this of concern?
spleen serves as a reservoir for blood therefore it can lose a lot of blood quickly if it sustains a laceration or rupture
US is sometimes called upon to inspect the spleen after a blunt force trauma. What type of splenic injury would the sonographer be looking for?
splenic laceration or rupture aka splenic fracture
