Spleen:
Part of the _________ system
Main function is to filter ________ blood Active in
blood formation (__________) during the initial part of fetal
life
reticuloendothelial
peripheral
hematopoiesis
Spleen:
Plays an important role in body�s defense against ______
Often affected by ________ disease processes Rarely the
_________ site of disease
disease
systemic
primary
Spleen:
Lies in the ______________ with its axis along the shaft of
the _____ rib Lower pole extends forward as far as the
midaxillary line. Is an ____________ organ and is covered
entirely with peritoneum except for a small area at its hilum, where
the vascular structures and lymph nodes are located.
left hypochondrium; tenth
intraperitoneal
Spleen:
_______ capsule covers the spleen with peritoneum. In
most adults, a portion of the splenic capsule is firmly adherent to
the fused _____ mesentery, anterior to the upper pole of the left
kidney. This produces a �_______� of the spleen that can be
helpful in distinguishing intraperitoneal from pleural fluid
collections.
Protective
dorsal
bare area
Spleen:
Variable size and shape; Measured on a longitudinal image from
the upper margin (near the diaphragm) to the inferior margin at the
long axis
Normal measurements for average adult are ___ cm long,
___ cm wide, and __ to ___ cm thick.
12; 7; 3 to 4
Relationships:
The tail of the pancreas lies _________ to the stomach and
lesser sac as it approaches the hilum of the spleen and splenic
vessels. The left kidney lies ______ and __________ to the
spleen.
posterior
inferior and medial
Wandering Spleen:
Embryologic anomaly of the dorsal mesentery fails to fuse with
the _______________ without supporting ligaments of the spleen.
Presenting symptoms may include an abdominal or pelvic mass,
intermittent pain, and volvulus (splenic
torsion).
posterior peritoneum
What is a spleen that hasmigrated from its normal location in
the left upper quadrant?
�Wandering spleen�
Asplenia, or _______ __________, is the complete absence
of the spleen. Rare and, by itself, causes no
difficulties May occur as part of a major congenital
abnormality
splenic agenesis
Splenic Agenesis:
Asplenic or polysplenia syndromes are associated with complex
cardiac malformations, bronchopulmonary abnormalities, or visceral
heterotaxia. Visceral _______ is the anomalous placement or
transportation of viscera or parts. Anomalous placement of organs or
major blood vessels includes a horizontal liver, malrotation of the
gut, and interruption of the inferior vena cava with azygos
continuation.
heterotaxy
Splenic Agenesis:
Situs ______: Normal arrangement of asymmetric body
parts. Situs _______: Mirror image condition. Situs
__________: Describes anatomy that falls in between situs solitus
and situs inversus.
solitus
inversus
ambiguous
Splenic Agenesis:
Patients with asplenia may have bilateral _____ _________
Two morphologic right lungs, midline location of the
liver, reversed position of the abdominal aorta and inferior vena
cava, anomalous pulmonary venous return, horseshoe kidneys
right sidedness
Patients with ________ have bilateral left sidedness
Two morphologic left lungs, left-sided azygos
continuation of an interrupted inferior vena cava, biliary
atresia, absence of the gallbladder, gastrointestinal malrotation,
cardiovascular abnormalities
polysplenia
Accessory spleen, aka: _____________
More common congenital anomaly; may be found in up to ___% of
patients Appears as a homogeneous pattern similar to that of
the spleen Usually found near the ______
or inferior border of the spleen
Splenunculus
30%
hilum
A soft organ with elastic properties that allow it to distend
as blood fills the venous sinuses: ________ These
characteristics are related to the spleen�s function as a blood
______. Within the lobules of the spleen are tissues called
_____. Has both _____ pulp and _____ pulp
Spleen
reservoir
pulp
red and white
Red Pulp:
Consists of splenic sinuses alternating with splenic
cords Red blood cells squeeze through ________ and enter the
venous sinuses.
capillaries
Red Pulp:
Older, more fragile red blood cells may rupture as they make
this passage; the resulting cellular debris is removed by phagocytic
macrophages located within the splenic sinuses.
_______ engulf and destroy foreign particles, such as
bacteria, that may be carried in the blood as it flows through the
sinuses.
Macrophages
The spleen functions as an organ of the reticuloendothelial system,
four of its functions are:
Production of ________ and ________ cells
Production of _______ Storage of ____
Storage of other metabolites
lymphocytes and plasma
antibodies
iron
Other functions of the spleen include:
Maturation of the surface of __________ (RBC)
Reservoir Culling Pitting Disposal of
senescent or abnormal ________ (RBC) Functions related to
______ and leukocyte lifespan
erythrocytes
erythrocytes
platelet
Phagocytosis of erythrocytes and the breakdown of _______ occur
throughout the entire reticuloendothelial system; however, roughly
______ of the catabolic activity is localized in the normal
spleen.
hemoglobin
1/2
In splenomegaly the major portion of hemoglobin breakdown
occurs in the ______. Iron that is liberated is stored in
the splenic ______. In anomalies such as the hemolytic
anemias, the splenic phagocytes become ________
spleen
phagocytes
engorged
Erythrocytes (RBCs) pass through the spleen, and those the
spleen recognizes as abnormal or senescent are _______.
Normal function of the spleen keeps the number of circulating
erythrocytes with inclusions at a minimum.
destroyed
______ is the process of removing the nuclei from the red blood
cells. ______ is the process by which the spleen removes
abnormal red blood cells.
Pitting
Culling
The spleen also pools platelets in large numbers. The entry of
platelets into the splenic pool and their return to the circulation
is extensive. Essentially the platelets are stuck in the spleen and
not circulating in the blood. With _________, the splenic
pool may become so large that it produces
thrombocytopenia (deficiency of platelets in the
blood. This causes bleeding into the tissues, bruising, and slow
blood clotting after injury.)
splenomegaly
Hematocrit
Indicates the percentage of red blood cells per volume of
blood.
Abnormally low readings indicate _______ or ______
__________ within the body.
hemorrhage or internal bleeding
Bacteremia
Indicates the presence of bacteria within the body.
The term _______ indicates bacteria in the bloodstream.
Typical symptoms of fever and chills, along
with other medical conditions, may indicate the presence of an
infection.
sepsis
Leukocytosis
The increase in the number of white blood cells present in
the blood is usually a typical finding in ________.
This finding may also occur after surgery, in _________, or in
the presence of leukemia.
infection
malignancies
Leukopenia
Abnormal decrease in white blood corpuscles May be
secondary to certain medications or ______ _______ ___________.
bone marrow disorder
Thrombocytopenia
Abnormal decrease in platelets May be the result of
______ _________
internal hemorrhage
Splenic texture and patterns
The splenic parenchyma should have a fine uniform homogeneous
____ to _____-level echo pattern, as is seen within the liver
parenchyma. The texture of the spleen is actually considered
to be ____ echogenic than the liver. As the spleen
enlarges, the echogenicity increases further.
mid- to low
more
Spleen Size
Measured in long axis;___to ___ cm in length, ___ cm in the
anteroposterior diameter, and less than___ cm in thickness. (Usually
longer than the kidney)
Formula for splenic length in children: 5.7 + 0.31 x age (in
years)
Splenomegaly is diagnosed when the spleen measures more than
___ cm in the adult patient or more than the normal length in a
child.
8 to 12 cm; 7cm; 5cm
13
Patient Position and Technique:
Left upper quadrant (LUQ) Steep
decubitus
Drop down bed allows better access to LUQ
Alter respiration
...
Nonvisualization of the Spleen:
Atrophy of the spleen may be found in normal individuals; may
also occur in wasting diseases. In the final stages of atrophy, the
spleen may be so small that it is hardly recognizable. Advanced
atrophy is sometimes referred to as ____________. In
chronic hemolytic anemias, particularly sickle cell anemia,
excessive loss of pulp occurs, increasing fibrosis, scarring from
multiple infarcts, and incrustation with iron and calcium
deposits.
autosplenectomy
Splenomegaly:
Spleen involved in all systemic inflammations and generalized
hematopoietic disorders and many metabolic disturbances
Rarely the primary site of disease When the spleen is
involved in ____________ _______, splenic enlargement (splenomegaly)
usually develops.
systemic disease
Splenomegaly:
______ measurements are needed to determine the exact size of
the spleen. Evaluate splenic _______ and homogeneity to
determine whether a disease process involves the spleen.
Evaluate the splenic parenchyma and vascular patterns to confirm
changes in the size, texture, and vascularity.
volume
contour
Splenomegaly:
The spleen may grow to enormous size with extension into the
______ ______. The medial segment may cross the midline of
the abdomen to mimic a mass inferior to the ______ ______
_____.
iliac fossa
left lobe of the liver
What are the causes of splenomegaly? (9)
Congestion, Neoplasm, Storage disease, Infection, Hemolytic anemia,
Extramedullary hematopoiesis, Collagen-vascular disease, Trauma, and
Portal hypertension
Causes of CONGESTIVE Splenomegaly?
Heart failure, Portal hypertension, Cirrhosis, Cystic fibrosis,
Portal or splenic vein thrombosis, and Acute splenic sequestration
crisis of sickle cell disease
Amyloidosis:
A disease that occurs when substances called _____ ______ build up
in the organs. Frequently affects the heart, kidneys, liver, spleen,
nervous system, and gastrointestinal tract
Amyloid is an abnormal protein usually produced by cells in
the bone marrow that can be deposited in any tissue or organ.
amyloid proteins
Amyloidosis Sono Findings:
Spleen may be normal in size or enlarged, depending on the
amount and distribution of the amyloid. Two types of
involvement are seen�____ and _____
______: Amyloid is found in the walls of the sheathed arteries
and in the follicles but not in the red pulp. ________:
Follicles are not involved; the red pulp is prominently involved,
and the spleen is usually greatly enlarged and firm.
Nodular and diffuse
Nodular
Diffuse
Gaucher Disease:
Approximately __% of patients are under 8 years of age,
and __% are under 1 year of age. Clinical features follow
a chronic course, with bone pain and changes in skin
pigmentation.
50%; 17%
Gaucher Disease Sono Findings:
Splenomegaly, diffuse inhomogeneity, and multiple splenic
nodules (well-defined hypoechoic lesions) Nodules may be
irregular, _________, or mixed. Nodules represent focal
areas of Gaucher cells associated with fibrosis and
infarction.
hyperechoic
Niemann-Pick Disease:
A rapidly fatal disease that predominantly affects ____
______. Clinical features consist of hepatomegaly,
digestive disturbances, and lymphadenopathy.
female infants
Sickle Cell Anemia:
In early stages- enlarged Spleen with significant
congestion of the ____ pulp. Progressive
infarction/fibrosis and decreases in size until only a small mass
of fibrous tissue found (_________).
Sickle cells plug the vasculature of the spleen -producing
________ destruction of the spleen.
red
autosplenectomy
ischemic
Sickle Cell Anemia Sono Findings:
Different appearances depending on the disease state.
Acute sickle cell crisis occurs in children with
homozygous sickle cell disease with splenomegaly and a sudden ______
in hematocrit. In addition, these patients may develop a
subacute hemorrhage that appears as a _______ area in the periphery
of the spleen.
decrease
hypoechoic
Congenital Spherocytosis:
Is an intrinsic abnormality of the red cells that gives rise to
erythrocytes that are small and ________ rather than the normal,
flattened, biconcave disks. The spleen selectively destroys
spherocytes. Two results of this disease:
Production by the bone marrow of spherocytic erythrocytes
Increased _____ of these cells in the spleen
spheroid
destruction
Hemolytic Anemia:
Disorder characterized by chronic premature destruction
of ____ ______ _____.
Anemia may be minimal or absent, reflecting the ability
of the bone marrow to increase production of red blood cells.
red blood cells
Autoimmune Hemolytic Anemia:
Can occur in its primary form without underlying disease.
May be seen as a secondary disorder in patients already
suffering from a disorder of the reticulo-endothelial or
hematopoietic systems such as:(________, ________, or infectious
mononucleosis).
lymphoma, leukemi
Autoimmune Hemolytic Anemia Sono Findings:
Splenic changes are dominated by the underlying disease in its
secondary form. The spleen is variably _______ in its
primary form.
enlarged