Spleen Flashcards
When does the spleen begin to develop in embryologic development?
5th week of gestational age
What role does the fetal spleen play during development?
producing red and white blood cells
When does the spleen begin hematopoiesis?
11th week of gestational age
When do the lobulations of the fetal spleen smooth out?
5-6 weeks
Where does the fetal spleen originate from?
mesoderm cells in the dorsal mesogastrium
production of blood cells (RBCs, WBCs, platelets)
hematopoiesis
What is the single largest mass of lymphoid tissue in the body?
spleen
T or F: Since the spleen is a component of the immune system, removal can cause adverse side affects
False.
It can be removed without adverse side affects
T or F: the spleen is often affected by a systemic disease process and is rarely the primary site of disease
True.
RBC
erythrocyte
process of making RBCs
erythropoiesis
a cell that engulfs and consumes foreign material and debris
phagocyte
removal of worn out and abnormal RBCs and platelets from the bloodstream
phagocytosis
the spread of an infection from its initial site to the bloodstream
sepsis
Donning a gown, mask, and gloves because the pt is immunocompromised because they have a low number of neutrophils
neutropenic precautions
iron containing, oxygen carrying pigment of RBCs
hemoglobin
% of RBCs within your blood volume
hematocrit
located medially in the spleen; where the vasculature enters/exits
splenic hilum
has the responsibility of phagocytosis; found in the spleen, liver, lymph nodes, alveoli, brain, blood vessels, mucous membranes
reticuloendothelial system
where worn-out RBCs and blood borne pathogens are destroyed; consists of splenic sinuses and splenic cords
red pulp
where immune system functions take place; consists of lymphatic tissue containing lymphocytes and monocytes that continually digest harmful pathogens entering the blood stream
white pulp
non-penetrating trauma
blunt force trauma
The spleen is a __1___ organ covered by a ___2___ except where vessels enter/exit at the hilum.
- peritoneal
- peritoneum
T or F: the spleen has a strong capsule
False.
The spleen does not have a strong capsule; making it fragile and susceptible to injury
What is the length of the spleen?
8-13 cm
What is the height (AP) of the spleen?
7-8 cm
What is the width of the spleen?
3-4 cm
What is the normal volume of the spleen?
60-200 mL
What is the splenic index?
107-314
What are supporting ligaments of the spleen?
- splenorenal ligament
- phrenicocolic ligament
- gastrosplenic ligament
The spleen lies in which region and quadrant?
LT hypochondrium/LUQ
The spleen lies ______ to the stomach and pancreas tail?
posterolateral
The spleen lies _______ to the LT colic flexure?
posterior
The spleen lies _______ and _______ to LK?
superior, lateral
The spleen lies ________ to the LT hemidiaphragm and LT lung?
anterior
The spleen lies _______ to ribs along dorsal abdomen?
anterior
courses horizontally along the superior border of the tail of the pancreas; tortuous; SUP/ANT to splenic vein
splenic artery
courses horizontally along the inferior border of the tail of the pancreas; part of portal venous circulation?
splenic vein
What is the primary function of the spleen?
Remove…….from circulation
- old blood cells
- debris
- pathogens
- foreign substances
The spleen is a soft organ with elastic properties that allow it to distend; helps it act as a _______________?
blood reservoir
The spleen contains ________ of connective tissue which divides the spleen into lobules?
trabecula
What 2 tissues are within the lobules of the spleen?
- white pulp
- red pulp
Performs lymphatic function of spleen?
white pulp
Performs phagocytic function spleen?
red pulp
consists of splenic sinuses alternating with splenic cords (microscopic)?
red pulp
consists of Malpighian corpuscles (a type of lymphoid tissues that acts as a filter)?
white pulp
Red or white pulp contains RBCs and phagocytes?
red pulp
Produces antibodies, lymphocytes, and monocytes to aid in immune response?
white pulp
removing irregular RBCs from the blood stream?
culling
removal of nuclei from old RBCs by the spleen without destroying the actual cell?
pitting
What are the 4 major spleen functions?
- defense
- hematopoiesis
- RBC/platelet destruction
- storage
In the developing fetus, what produces RBCs and WBCs?
spleen
In an adult, what produces RBCs?
bone marrow
RBC production in adults are only done by the spleen in _________ _________?
severe anemia
What are the by products of cells being broken down?
- hemoglobin
- globin
- hemosiderin
- heme
What will develop if the number of blood cells stored within the spleen becomes excessive?
splenomegaly
a spleen that has migrated from its normal location in the LUQ?
wandering spleen
Splenule, spleneculus, supernumerary spleen are other names for what congenital abnormality?
accessory spleen
Which congenital anomaly may lead to splenic torsion?
wandering spleen
a common congenital anomaly usually found in splenic hilum or INF border of spleen?
accessory spleen
What is another name for splenic agenesis?
asplenia
An embryonic anomaly of the dorsal mesentery that fails to fuse with the posterior peritoneum that leads to failure of splenic ligaments to form properly?
wandering spleen
absence of the spleen; can be congenital or secondary to a disease?
splenic agenesis (asplenia)
development of multiple small pieces of splenic parenchyma?
polysplenia
normal arrangement of symmetric body organs?
situs solitus
mirror image arrangement of body organs?
situs inversus
the combination of correct-sided, and incorrect-sided organs
situs ambiguous / visceral heterotaxy
% of RBCs per volume of blood; low readings indicate hemorrhage or internal bleeding?
hematocrit
Indicates presence of bacteria in the body?
bacteremia
increase in WBCs; sign of infection?
leukocytosis
decrease in WBCs; may be secondary to medications or bone marrow disorder; interferes with the body’s ability to fight infection?
leukopenia
an abnormal decrease in platelets; may be due to internal hemorrhage?
thrombocytopenia
How long should a pt be NPO?
6-8 hours
What kind of TRX should be used for a spleen US?
2-6 MHz curvilinear
What is the normal echogenicity of the spleen?
isoechoic, slightly more echogenic than liver
What is commonly evaluated on ultrasound for imaging the spleen?
splenomegaly
How do you calculate splenic volume?
SAG x AP x TRV x .523
(length x height x width)
How do you calculate splenic index?
SAG x AP x TRV
(length x height x width)
enlargement of the spleen?
splenomegaly
enlargement of spleen, secondary to vascular congestion/liver failure?
congestion of the spleen
What occurs in acute congestion of the spleen?
hyperemia
(excess blood in a body part)
What occurs in chronic congestion of the spleen?
diffuse splenomegaly
What is the most common disease process encountered by a sonographer?
splenomegaly
This pathology can be seen secondary to RT sided heart issues, cirrhosis, PV HTN, PV thrombosis?
congestion of the spleen
The most common causes of this pathology are bacterial infection, viral infection (mono), PV HTN?
splenomegaly
an excessive build up of amyloid in tissues/organs; this build up is typically systemic and not only affecting the spleen?
amyloidosis
a waxy, translucent substance, composed primarily of protein fibers, that is deposited in various organs of animals in certain diseases?
amyloid
A type of amyloidosis where amyloid is found in walls of arteries and within the follicles, but not the red pulp?
nodular amyloidosis
A type of amyloidosis where the follicles are not involved, the red pulp is and the spleen is greatly enlarged/firm?
diffuse amyloidosis
a genetic disorder in which the body lacks an enzyme that breaks down lipids (fats)?
Gaucher’s Disease
Which type of Gaucher’s disease affects babies 2-3 mos?
Type 2
Which type of Gaucher’s disease is associated with anemia?
Type 1
Which type of Gaucher’s disease involves skeletal disorders, affects eyes, and breathing?
Type 3
What is the most common type of Gaucher’s disease?
Type 1
a decrease of RBCs within the bloodstream?
anemia
the rate of destruction by the spleen is greater than what the bone marrow can compensate for that leads to a decrease in RBCs within the bloodstream?
hemolytic anemia
immune system destroys RBCs; secondary to pts suffering from reticuloendothelial conditions such as lymphoma, leukemia, infectious mononucleosis?
autoimmune hemolytic anemia
RBCs are formed abnormally due to an abnormal hemoglobin protein that messes with the RBC’s ability to carry oxygen?
sickle cell anemia
What occurs in acute sickle cell anemia?
pts have an enlarged spleen
What occurs in chronic sickle cell anemia?
pts undergo autosplenectomy as the spleen becomes fibrotic and atrophies
This occurs when sickle-shaped cells attach to one another and obstruct vascular pathways?
sickle-cell crisis
inherited blood disorder that causes your body to have less hemoglobin than normal?
thalassemia
This condition is more common in people of African American, Caribbean, Middle East, Mediterranean, and Hispanic descent?
sickle cell anemia
hereditary type of anemia common in the Asian and Mediterranean population?
thalassemia
congenital condition in which an internal abnormality causes RBCs to have a spherical shape?
congenital spherocytosis
the bone marrow produces an excess of RBCs, with an increase in RBC mass and hemoglobin concentration?
polycythemia vera
Histoplasmosis and tuberculosis are the most common causes of this pathology?
granulocytopoietic abnormalities (splenic granulomas)
What is another name for granulocytopoietic abnormalities?
splenic granulomas
Most commonly injured as a result of blunt force trauma to the abdomen?
splenic trauma
What are the 2 outcomes of blunt force trauma?
- capsule is intact and there is subcapsular/intraparenchymal hematoma
- capsule ruptures and a focal or free intraperitoneal hematoma
A “double contour” sign depicts what pathology?
splenic trauma
splenic tissue that has been deprived of oxygen and will eventually die?
splenic infarct
With splenic trauma, as time passes, the hematoma becomes more ________?
anechoic/sonolucent
wedge-shaped hypoechoic spleen tissue indicates what pathology?
splenic infarct
the most common benign tumor of the spleen?
hemangioma
rare, may be solitary or multiple, and consists of lymphoid tissue or normal splenic tissue
hamartoma
This pathology is asymptomatic until it gets big enough to cause splenic rupture or peripheral problems
hemangioma
asymptomatic, can have both cystic and solid components, and is generally hyperechoic?
hamartoma
very rare primary malignant neoplasm arising from the endothelium?
hemangiosarcoma
What helps prevent abscess formation in the spleen?
reticuloendothelial system
space of the peritoneum posterior to the stomach?
lesser sac
This infection is spread to the spleen from a distant infection OR from an inflammatory process from adjacent organs?
splenic abscess
What is the most common site for abscess formation?
splenic portion of the lesser sac
