week 12 - spleen Flashcards
spleen is part of the ____ system
reticuloendothelial
spleen is a intraperitoneal organ in the ___
LUQ / left hypochondrium
t/f: spleen is essential to life
false - it is NOT essential
Responsible for the phagocytosis of damaged/old cells, foreign material and pathogens
spleen
Active in ___ during the first part of fetal life
hematopoiesis
spleen is composed primarily of ___ tissue
lymph
spleen is ____ to the body and fundus of the stomach and pancreatic tail
posterolateral
spleen is ___ to the left colic gutter
posterior
left kidney is ___ to the medial section of spleen
posteroinferior / inferomedial
diaphragm, lung, pleura, and ribs are ___ to spleen
posterior
only portion of spleen not covered by peritoneum
splenic hilum
what protects the spleen
ribs
spleen is lateral to
stomach and lesser sac
longest dimension of spleen should not exceed
13cm
___ structure with ___ superior surface and ___ inferior surface
ovoid
convex
concave
describe the contour of the spleen
smooth
why do we look at the spleen
evaluate shape
t/f: spleen is highly vascularized
true
spleen is covered in ___ except for the ___
peritoneum
hilum
spleen is composed of __ and ___ pulp
white
red
Lymphatic tissue that surrounds and follows the smaller splenic arteries,
Consists of the Malpighian corpuscles
white pulp
Small nodular masses of lymphoid tissue attached to smaller arterial branches
Malpighian corpuscles
Lymphoid tissue follicles surround ___ and are scattered throughout the ___
arteries
spleen
Red pulp is ___ vascular than white pulp
more
Contains large numbers of RBCs
red pulp
red pulp surround ___
venous sinuses
red pulp consists of
splenic sinuses and cords
capillaries are ___ thus, RBC __ enter the venous sinuses
permeable
can
vascular supply to spleen
splenic artery from celiac trunk
splenic artery courses ___ towards the spleen
laterally
___ and ___ branches arise from the splenic artery
pancreatic and gastric
splenic artery at hilum branches into ___ arteries
2-4 lobar
lobar arteries branch into ___ then into ___ that terminate in ___
lobular
splenic arteries
capillaries
helps with the filtering function of the spleen
capillaries
The capillaries in spleen anastomose with tiny venous sinuses that form splenic ___
venules
converge to form the splenic vein
venules
splenic vein course medially to the confluence with ___ to form the ___
superior mesenteric vein (SMV/IMV)
portal vein
Nerves to the spleen accompany the ____ artery and are derived from the ____
splenic
celiac plexus
lymph vessels emerge from ___ and pass through other lymph nodes along the ___ artery then drain into the ____ nodes
splenic hilum
splenic
celiac
spleen acts as reservoir for
blood
4 major function of spleen
- defense
- hematopoiesis (produce RBC & WBC)
- RBC and platelet destruction
- blood reservoir
spleen produces (6)
lymphocytes phagocytes plasma cells antibodies RBC WBC
spleen stores ___ and ___
iron
metabolites
spleen regulates the life span of
platelets and leukocytes
type of cell destroys invading microbes
platelet
what type of cells in spleen are directly involved in immune response
memory cells
__ pulp produces lymphocytes and monocytes for ingestion and digestion of pathogens
white
when is the spleen involved in hematopoiesis
- in developing fetus
- in adult suffering severe hemolytic anemia
what is hematopoiesis
production of RBC and WBC
what is culling
removal of abnormal RBC
what is pitting
removal of nuclei from old RBC without damage to the cell
filter that help with phagocytosis of old RBC
red pulp & sinuses
what happens to iron from hemoglobin of RBC removal that is not used immediately to make more RBC
transported to liver and bone marrow for storage
what gives the spleen the ability to act as blood reservoir and store RBC
high smooth muscle content
where is blood stored in the spleen
red pulp
t/f: blood can be released instantaneously from red pulp if needed
true
what is splenomegaly
too many cells and spleen becomes enlarged
Indicates the percentage of RBCs per volume of blood.
hematocrit
abnormally low hematocrit readings indicate ___
hemorrhage or internal bleeding within body
Indicates the presence of bacteria within the body.
bacteremia
term for bacteria in the bloodstream
sepsis
Typical symptoms of ___: fever and chills, along with other medical conditions
bacteremia
The increase in the number of WBCs present in the bloodstream
leukocytosis
WBC ___ is usually a typical finding in infection, after surgery, in malignancies, or in presence of leukemia
increase
Abnormal decrease in white blood corpuscles
leukopenia
leukopenia may be secondary to certain medications or ____disorder
bone marrow
Thrombocytopenia
abnormal decrease in platelets
thrombocytopenia May be the result of _____
internal hemorrhage
splenic masses are ___
rare
sonography can help assess splenic damage from ___, such as rupture or hemorrhage
blunt trauma
most common use of sonography for spleen is to detect ____
enlargement or splenomegaly
long axis measure of spleen greater than ___ indicates splenomegaly
13cm
spleen is homogeneous with ___ echogenicity
medium grey
___-echoic to ____-echoic compared with normal liver
isoechoic
hypoechoic
spleen is ___-echoic compared to renal cortex
hyperechoic
wall margins of spleen are ___
smooth
why may spleen be difficult to visualize?
bowl gas or ribs
what are the multiple hyperechoic foci that may be identified throughout the spleen
small calcifications
spleen typically best seen with ___
intercostal window
in ___ plane, sagittal view with the spleen and LK can be visualized
coronal
most common congenital anomoly of spleen
accessory splenule
Typically found near the hilum or inferior border of spleen, homogeneous isoechoic mass
accessory spleen
rare major congenital abnormality
asplenia
asplenia
complete absence of spleen
polysplenia
multiple small accessory spleens
Embryologic anomaly of the dorsal mesentery fails to fuse with the posterior peritoneum without supporting ligaments of the spleen
wandering spleen
when spleen is found migrated away from its normal location in the LUQ
wandering spleen
The spleen is located in the abdominal cavity outside of where it should be
ectopic
In thin individuals the liver can be seen ___ to the spleen
superior
things that can simulate a mass on spleen (3)
tail of pancreas
fundus of stomach
superior liver
associated tests to visualize spleen
- x-ray
- CT
- MRI
hypoechoic mass in spleen
splenic metasis
multiple hypoechoic splenic lesions throughout spleen parenchyma
lymphoma
hematoma caused by ___
trauma (internal blood collection )
in what plane is spleen length measured
sagittal
in what plane is spleen width measured
transverse
in what plane is spleen depth measured
sagittal or trv from hilum to edge
Typically have ___- ___ lymph nodes
500 - 600
contains: Lymph, lymphatic vessels, lacteals, lymph nodes and spleen, bone marrow and thymus gland
lymphatics
lymphatics collect and transport excess fluids, lymph, from ____ spaces back into the venous system
intertitial
Absorb fats from small intestine and transport them to the liver
lymphatics
lymphatics utilize ___ tissue and organs to produce cells that fight (immune system) and dispose of foreign material
lymphoid
t/f: lymph nodes are routinely seen on ultrasound
false
Normal nodes are ____
smaller than the tip of a finger (less than 1 cm)
t/f: with pressure from the probe, lymph nodes change shape
false - remain constant shape
enlarged lymph nodes should be ___
reproducible
abnormal lymph node common sites
- paraaortic/ paracaval near GV
- peripancreatic area
- renal hilar area
- mesenteric region
__ frequency probe for superficial nodules
high
deep nodules seen with ___ frequency probe
low
shape of normal lymph nodes
ovoid
parts of lymph node (2)
- cortex
- hilum
part of lymph node that is hypoechoic concentric, containing marginal sinus and lymphoid follicles
cortex
part of lymph node that is echogenic/ hyperechoic with multiple reflective interfaces of blood vessels, fat and the central sinus
hilum
an abnormal decrease in platelets may be the result of
internal hemorrhage
in adults, the spleen is composed primarily of
lymph tissue
a spleen that has migrated from it’s normal location is termed
wandering spleen
all of the following are functions of the spleen except:
- production of plasma cells
- production of lymphocytes
- destruction of RBC
- destruction of WBC
destruction of WBC
when describing a normal LN:
- a hyperechoic hilum with hypoechoic cortex
- a circular structure
- a hypoechoic hilum and hyperechoic cortex
- a solid hypoechoic ovioid structure
-a hyperechoic hilum with hypoechoic cortex
which of the following is recycled into iron by the spleen
hemoglobin
lymph nodes are located in all but the following:
- groin
- axillae
- abdomen
- all of the above are locations of LN
all of the above are ocations of LN
the hilar area of the spleen is
- not covered by peritoneum
- comparable to the hilum of the kidneys
- contains arteries and veins
- all of the above
all of the above
the splenic artery arises from the
CT
the splenic vein courses along the posterior border of the
pancreas
the primary component of white pulp is:
- malpghian corpuscles
- epithelial cells
- red and pink pulp
- splenic cords
-malpghian corpuscles
the spleen is anterior to the
- diaphragm and stomach
- tail of pancreas
- left lung
- left kidney
left lung
the echogenicity of the spleen can be described as which of the following:
- medium level echoes
- anechoic
- low level echoes
- high level echoes
medium level echoes
t/f: the spleen is posterolateral to both the pancreatic tail and part of the large intestine
true
