Spleen Flashcards
The stomach is _ to the splenic hilum
Anterior and medial
Functions
Breakdown hemoglobin, form bile pigment, form antibodies, resovoir for blood.
Iron storage, defense against disease, erythropoiesis
The tail of the panc is ___ to the st
Posterior
The left kid is __ to the spleen
Inferior medial
The tail of the panc is ___ to the upper pole of the left kid
Anterior
Name 5 structures that appear as cystic splenic masses
Cystic degenerations of infarcts or hematomas
Cyst assoc with PCK
Parasitic cysts (echinococcol)
Epidermoid cyst
Panc pseudocyst
Spleen location, length
Intraperitoneal
9-11 rib LUQ
< 13 cm L
Covered by capsule and peritoneum except hilum
Ligaments
Lienorenal
Gastrosplenic
Phrenocolic
White and Red Pulp
Filters blood
White pulp consist of lymphatic tissue, lymphatic follicles, antibody production
Red pulp is framework of reticular cells and fibers known as cords of Billroth that surround the venous sinusoids. Monocytes and macrophages
Aplasia
No spleen
Rare
Assoc with lethal malformations (❤️)
Hypoplasia
Small spleen
More common than Aplasia
Accessory spleen
Extra small spleen Usually in hilum < 5 cm Isoechoic with spleen May look like tumor or lymphadenopathy
Connecting vessel from accessory spleen to normal spleen
Ectopic spleen / wandering spleen
Due to lack of ligaments, can torse & infarct
< .5%
Females 90%
Prophylactic splenectomy
Assoc with extreme weight loss, weak abd muscle, splenomegaly, multiparous females
Polysplenia
2 spleens
Assoc with vasc anomalies, biliary atresia, CHD, abnl situs
Reasons for splenomegaly
Chronic inflammatory disease, malaria, TB, portal HTN, cirrhosis, hemolytic disease, sickle cell, thalecemia, infiltrative disease, leukemia, Hodgkin’s lymphoma, metabolic disease, gauschers’s, Nieman Picks, trauma, hematoma
Portal HTN, aids, infection
Splenomegaly
> 12 cm L
Cyst
PKD, simple cyst, acquired post inflammatory, trauma, parasitic, neoplastic
Abscess
Due to infection
Usually multiple
Fever, abd pain, lt chest & shoulder pain
Complex, ring down from gas
Infarcts
Wedge shape hypo lesion, no Doppler
Caused by occlusion of vessels
Sudden onset of LUQ pain
Usually from emboli (❤️ clot)
MC assoc with endocarditis
Leukemia, sickle cell anemia, lymphoma, vasculitis, valvular heart disease, pancreatitis, mets
Wedge shape
Round, well defined, hypo initially then hyper
Trauma
Organ most often damaged with trauma
Car accidents MC cause
LUQ pain, dec hematocrit, syncope, hypotension
Assoc with rupture
Splenomegaly, hematoma may appear any echogenicity, splenic laceration/fracture,
free fluid, sub capsular hematoma, perisplenic hematoma, splenic laceration
Structures in contact with the spleen
Left hemidiaphragm
Stomach
Pancreas
Splenic flexure of colon
Best spleen long axis view
Intercostal coronal view with patient supine
Portal HTN shows
Moderate splenomegaly and dilated tortuous vessels at the splenic hilum
Evaluate liver and portal vein
Pancreatic tails are ____ to spleen
Inferior medial
Spleen echo texture
Homogeneous, mid to low level echoes
Transducer for splenomegaly
5MHz curvilinear
Spleen
LUQ, intraperitoneal, lies between the fundus of the stomach and the diaphragm, meas < 12 cm, normal spleen dec in size and weight with age
Pitfall
Inter coastal produces rib shadowing
Hepatomegaly left liver lobe may be mistaken for spleen
Mass in tail of panc may be confused with splenic mass
Accessory spleen may be confused with a large lymph node
Histoplasmosis US findings
Multiple focal bright echogenic granulomatous lesions throughout spleen
Splenic vein drains into
Portal Vein
Rupture
Enlarged spleen with hx of trauma suggests rupture
Granulomatous Disease / ca+
Histoplasmosis: fungus, bird poop airborne spores, affects lungs,
Tuberculosis
Pneumocystis Carinii
Angiosarcoma
Cancer, assoc with carcinogens, LUQ mass, anemia 70%, poor prognosis
Hodgkin’s Disease
Lymphoma
Mets
Melanoma is MC mets to spleen. Other: lung, breast, ovary, stomach, prostate.
Target lesion
Benign lesions
Hemangioma, hamartoma, lymphagioma
Hemangioma MC
AIDs
Splenomegaly
W: Hodgkin’s, TB, Kaposi’s Sarcoma, Lymphoma, = hypo lesions
W: pneumocystis = numerous echogenic foci
