Anatomy of spleen & its applied aspect

1. DEPARTMENTAL
PRESENTATION OF
ANATOMY
MANJU P S
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2. *SUBJECT*
Anatomy of spleen & its applied
aspect
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3. INTRODUCTION
 Spleen(Greek splen and Latin lien) is a lymphatic
organ connected to the blood vascular system. it acts
as a filter for blood and plays an important role in the
immune responses of the body.
 The Spleen develops as part of the vascular system in
the part of dorsal mesentery that suspends the
developing stomach from the body wall.
 The spleen is an organ found in virtually all
vertebrates. Similar in structure to a large lymph node,
it acts primarily as a blood filter.
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4. POSITION
 The spleen lies obliquely along the long axis of the
10th rib.Thus it is directed downwards, forward and
laterally, making an angle of about 45 degrees
with the horizontal plane.
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6. DIMENSIONS
The spleen is soft , highly vascular and dark purple in
colour.The size and weight of spleen are markedly
variable.On an
average the spleen is 1 inch thick, 3 inch broad,5 inch long,7
ounces in weight, and is related to 9th to 11th ribs.
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7. *LOCATION*
 The Spleen is a wedge-shaped organ lying mainly in the left
hypochondrium, and partly in the epigastrium, it is wedged
in between the funds of the stomach and the diaphragm.
 The spleen lies against the diaphragm,in the area of rib
9th,to rib 10th.
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11. EXTERNAL FEATURES
 The spleen has two ends ,three borders and two surfaces
and 2 angles and hilum.
 TWO ENDS-
1 -The anterior or lateral end is expanded and is more like a
border.It is directed downwards and forwards, and reaches
the midaxillary line.
2-The posterir or medial end is rounded.it is directed
upwards,backwards and medially.
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12. …………EXTERNAL FEATURES
 Three borders-
 1-The superior border is charcteristically notched near the
anterior end.
 2-The inferior border is rounded.
 3-The intermediate border is also rounded and is directed
to the right.
 Two surfaces-
1.The diaphragmatic surface is convex and smooth.
2.The visceral surface is concave and irregular.
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13.  Two Angles-
 1.Anterobasl angle-It is the junction of superior border with
lateral or anteriror end.
 2.Posterobasal angle-junction of inferior border with
lateral or anterior end of spleen.
 Hilum-hilum lies between superior and intermediate
borders it is peirce by branches and tributaries of splenic
vessels.
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15. *RELATIONS*
(a)Peritoneal relations
(b)Visceral relations
Peritoneal relations
 The spleen surrounded by peritoneum and is suspended by following
ligaments.
 1-Gastrosplnic ligament extends from the hilum of the spleen to the
greater curvature of the stomach.
 2-Lienorenal ligament extends from the hilum of the spleen to the
anterior surface of the left kidney.
 3-phrenicocolic ligament is not attached to the spleen, but supports its
anterior end.
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17. ………….. Relations
Visceral Relations
Visceral surface-
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18. Four impression present are visceral surface of spleen for
abdominal organ and other structure-
1.Gastric impression
2.Renal impression
3.Colic impression
4.Pancreatic impression
Hilum lies on the inferomedial part of the gastric impression along
the long axis of the spleen.
Diaphragmatic surface
The surface separates the spleen from the costodiaphragmatic
recess of pleura, lung and 9th ,10th ,11th ribs of the left side.
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20. Blood supply of the spleen
Arterial supply-the spleenic artery the largest branch of coeliac trunk
takes tortuous course to the left along the superior border of the
pancreas. It travels in the splenorenal ligament and divides in to
numerous branches,which enter the hilum of the spleen.As the splenic
artery passes along the superior border of the pancreas.It gives off
numerous small branches to supply the neck, body and tail of the
pancreas.
 Approaching the spleeen the splenic artery gives off short gastric
arteries,which pass through the gastrosplenic ligament to supply the
fundus of the stomach. It also gives off the left gasto-omental
artery,which runs to the right along the greater curvature of the
stomach and anastomoses with the right gasto-omental artery.
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22. Venous supply
 The splenic vein is formed at the hilum of the spleen.it runs a straight
course behind the pancreas.it joins the superior mesenteric vein
behind the neck of the pancreas to form of portal vein.its tributaries
are the short gastric,left gastroepiploic,pancreatic and inferior
mesentric veins.
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23. Histology of spleen

There two main types of tissue in the spleen are specialised for its
two main functions:
 White pulp contains lymphoid aggregations, mostly
lymphocytes, and macrophages which are arranged around the
arteries. The lymphocytes are both T (mainly T-helper) and B-
cells.
 Red pulp is vascular, and has parencyhma and lots of vascular
sinuses. These are sinuosoids - a specialised type of capillary,
which is very leaky.
 The lining endothelial cells have wide slits between their
lateral margins, that act as a filter. The blood cells have to move
through these slits, before they can leave the spleen and worn
out, or defective blood cells are damaged during this process. The
damaged cells are then phagocytosed by the numerous
macrophages in the red pulp, that lie just next to the sinusoids.
The spleen is covered by a dense capsule, and there are
connective tissue trabeculae, which provide internal support for
the spleen, and carry the blood vessels into the spleen. 23

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26. Nerve supply –sympathetic fibres are derived from the coeliac plexus.
they are vasomotor in nature. They also supply some smooth muscle
present in the capsule.
Functions of spleen-
1.Phagocytosis-The spleen is an important component of the
reticuloendothilial system.
2.Haemopoiesis-The spleen is an important haemopoietic organ during
life.Lymphopoiesis continues through life.
in adult spleen haemopoisis can restart in certain diseases,like chronic
myeloid leukemia and myesclerosis.
3.Immuneresponses-Under antigenic stimulation, there occurs increased
lymphopoiesis for cellular responses and incrased formations of
plasma cells fo the humoral responses.
4.Storage of RBCs-Red blood cells can be stored in the spleen and
released in to the circulation when needed.
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27. DEVELOPEMENT
 Spleen develops in the mesoderm in the cephalic part of
left layer of dorsal mesogastrium.The development occurs
during sixth week of intrauterine life.Number of nodules
develop which soon fuse to form a lobulated spleen
notching of the superior border of the adult spleen is an
evidence of its multiple origin.
 Accessory spleens or Spleniculi-
 These may be found In the derivatives of the dorsal
mesogastrium i.e. gastrosplenic ligament,lienorenal
ligament,gastrophrenic ligament and greater omentum.
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28. APPLIED ANATOMY
 1-Palpation of spleen-A normal spleen is not palpable. An enlarged spleen
can be felt under the left costal margin.
 2-Splenomegaly-Enlaregement of the spleen is called splenomegaly.
sometimes the spleen becomes very large.it then projects towards the
right iliac fossa in the direction of the axis of the tenth rib.
 3.-Splenctomy-Surgical removal of the spleen is called splenctomy.During
this operation damage to tail of the pancreas has to be carefully avoided.
 4.-Splenic puncture-Spleen can be punctured through the 9th or 10th
intercostal space in the mid axillary line using a lumbar puncture needle.
 Intrasplenic presuure is an indirect record of the portal presssure.splenic
venography reveals and confirm the enlarged portosystemic
communicatiuon in cases of portal hypertention.
 Splenic infarction-the smaller branches of splenic artery are end
artery.Their obstruction (embolism) result kher’s sign.
 Spleen is a danger of trauma to the lower thoracic cage especially 9th, 10th
and 11th ribs.
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29. …..APPLIED ANATOMY
 Pain of splenic tissue is poorly localised.it is also reffered to
the epigastrim region.Stretch of the splenic capsule
produces localized pain posteror part of left
upper(quadrant).
 Partial splenectomy-since there are segmental branches of
the splenic artery,only one segment can be removed
according to the state of spleen.
 After splenectomy ,spleen can be cut in to small pieces and
these can be implanted within the greater omentum.
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30. THANKS
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