topic 14: The spleen: anatomy, blood supply and histology

Question 1

location

Answer 1

-located in left hypochondriac region of abdomen
-post to stomach
-ant to hemidiaphragrm @ level of ribs 9 to 10
-medial to it is the left kidney
-superiorly the diaphragm
-inferiorly rest on left colic flexure

Question 2

general info

Answer 2

-largest lymphatic organ
-purple in color & bean shaped
-wrapped in fibrous elastic capsule allowing to expand in significantly when needed
-its an intraperitoneal organ mpeaning its covered with visceral peritoneum everywhere except @ hilum.

-Neighbouring organs leave impression
a.diaphragmatic/lat. surface : spleen lean unto adjacent part of diaphragm i.e lat. parl is slightly convexed
b.medial surface- has 3 areas of impression
i.colic area: impression of left colic flexure
ii.gastric a: impression of stomach
iii.renal a: impression of left kidney.
at the center of the media surface there is the hilum
(remember drawing)

Question 3

The three ligaments that attach to splen

Answer 3

1.Gastrosplenic lig - connect to hium w/ greater curvature of stomach & contains short gastric vessels and left epiploic arteries and viens
2.Splenorenal - connects to hilum with left kidney & transmits splenic a & v
3.Phrenicocolic - originates from colo & known as sustentaculum lienis

Question 4

function of spleen

Answer 4

Filtration of Blood: Removes old or damaged red blood cells and pathogens.

Immune Response: Initiates immune responses by activating lymphocytes in the white pulp.

Iron Recycling: Macrophages in the red pulp break down hemoglobin and recycle iron.

Storag: Acts as a reservoir for blood and platelets.

Hematopoiesis: In fetal life, contributes to the production of blood cells.

Question 5

histology of spleen

Answer 5

-enclosed in capsule made of dense fibrous dense CT that give structural support & protection
-capsula penetrates as trabecula that split organ in lobules & provides passageway for vessels
-white pulp: a.made of Periarteriolar Lymphoid Sheath; made mostly of T-lymphocytes, it acts as the site for T-cell activation and immune response initiation. It surrounde central arteries- they supply blood to WP and surrounding areas
b.has splenic nodule: areas with mainly Bcells-where thet activate & produce antibodies

-Red pulp: makes up most of the spleen; made of
a.splenic cords/cord of Billroth: made of reticular CT with agranulocytes & plasma cells. They filter blood by removing old & damaged rbc & pathogens
b.venous sinuses: larg iregular vascular space lined with specialized endothelial cell with gaps which allow for the passage of blood cells, facilitating filtration