Spleen Flashcards
1
Q
Spleen CT protocol
A
- Non-Contrast
- Arterial phase (30 sec)
- Portal venous phase (60 sec)
2
Q
Spleen anatomic anomalies
A
- Accesory spleen (splenules)
- Wandering spleen
- Splenic Regeneration/Splenosis
3
Q
Splenomegaly Definition and causes
A
- Splenomegaly: Size >12 cm.
- Massive splenomegaly: >20 cm.
- Causes: Myeloproliferative, infective, inflammatory, congestive and infiltrative categories.
4
Q
Spleen Cystic lesions (4)
A
- Posttraumatic Cysts.
- Congenital epithelium-lined cysts.
- Echinoccocal cysts.
- Pancreatic pseudocysts.
5
Q
Posttraumatic splenic cysts
A
-80% of all splenic cysts.
- Secondary to previous: hemorrage, infarction or infection.
- CT findings: Wall of variable thickness, internal debris, fluid levels, milk of calcium and calcification of the wall (30-40%).
6
Q
Congenital epithelium-lined splenic cysts
A
- True cysts with epithelium wall
- 20% of all splenic cysts
- CT findings: well-defined, water density, spherical, usually unilocular cyst with thin wall
7
Q
Echinoccocal splenic cysts
A
- Rare, only 2% of patients with hydatid disease.
- Larger mother cyst containing smaller daughter cysts near the periphery.
- Ring-like calcifications of the walls are common.
8
Q
Pancreatic pseudocysts (Spleen)
A
- Secondary to pancreatitis fluid gaining access to the splenic parenchyma
- CT findings: Subcapsular fluid collection of water attenuation + pancreatitis
9
Q
Spleen infarction
A
- Asymptomatic or left quadrant pain
- Causes: Atherosclerosis, arteritis, tumor, pancreatitis, systemic emboli or sickle disease
- Splenomegaly = Risk factor
- CT findings: Wedge-shaped low-attenuation defect that extends to the splenic capsule
- Also might not be wedge-shaped
10
Q
Splenic Bacterial abcesses
A
- Uncommon
- Immune system compromise, diabetes or IV drug abuse
- CT findings: Single or multiple low-density areas with ill-defined walls, which might be thickened and enhance with contrast, internal attenuation 20-40 UH, fluid level
- 20% might contain gas
11
Q
Splenic microabscesses
A
- Immunocompromised: AIDS, QT, lymphoma, leukemia, organ transplantation
- Opportunistic infection: Fungal (candida, pneumocystis jiroveci, aspergilllus, cryptococcus, histoplasma)
- Rare: CMV or mycobacterium tuberculosis
- CT findings: Multiple low-density 2-10 mm defects
- DD: Lymphoma, kaposi sarcoma, sarcoidosis and metastases
12
Q
Spleen lymphoma
A
- Primary is rare
- Secondary is more common: 1/3 of patients with lymphoma have splenic involvement
- The most common malignant tumor of the spleen
- CT findings: Multiple lesions (most characteristic) or diffuse infiltration, a solitary large mass might be a confluent deposit of lymphomatous tissue
- Might infarct
13
Q
Spleen Metastases causes
A
- Melanoma
- Lung
- Breast
- Ovarian
14
Q
Spleen metastases generalities
A
- Only 2-9% of patients with widespread malignancies
- 50% caused by melanoma
- CT findings: ill-defined, low density, but no water density, nodules with some degree of periptheral enhancement
- Melanoma: cystic metastases
15
Q
Spleen sarcoidosis
A
- 5-15% of patients
- Splenomegaly or single /multiple low-attenuation nodules with indistinct margins
- Local lymphadenopathy might be present
16
Q
Spleen Hemangioma
A
- Most common benign neoplasm of the spleen (still rare)
- Cystic or solid on unenhanced CT
- 1 to 15 cm size
- Central Punctate calcifications may be present or peripheral curvilinear calcifications
- Klippel-tranaunay-weber syndrome is associated with multiple spleen hemangiomas that look cystic
- Might enhance during arterial phase.
17
Q
Spleen Lymphangioma
A
- Uncommon splenic tumor
- Asymptomatic
- Benign, slow growing
- Small, multiple, homogeneous, cystic lesions, 15-35 UH, hypovascular, subcapsular
18
Q
Spleen Hamartoma
A
- Rare
- Similar to spleen hemangioma
- Beningn lesion
- CT: Low attenuation to isointense, slow enhancement, isodense on delayed phase
19
Q
Spleen Angiosarcoma
A
- Rare malignancy
- Agressive
- Widespread metastases: Lung, bone, liver
- CT: Multiple enhancing nodules with irregular and poorly defined contours, might also appear as a complex mass of cystic and solid components that enhances irregularly
- Splenomegaly usually present
20
Q
Splenic calcifications
A
- Common, usually from histoplasmosis or tuberculosis
- Multiple small focal calcifications
- Larger might be from: previous infection, infarction or trauma.
