Retroperitoneum

Question 0

What are the borders of the retroperitoneum?

Answer 0

Parietal peritoneum (anterior)
Transverse fascia (posterior)
Diaphragm
Pelvic floor

Question 1

What organs are held in the retroperitoneum?

Answer 1

Aorta
IVC
Pancreas
Kidneys and adrenals
Lymph nodes
Crura and psoas muscles
Uterus

Question 2

Which are the compartments of the retroperitoneum?

Answer 2

ARP - Anterior pararenal
PR - perirenal
PPR - post-pararenal

Question 3

Indications for retroperitoneum imaging

Answer 3

Pulsatile abdominal mass
Fever of unknown origin
Unexplained decreased hematocrit
Possible renal mass
Possible lymphoma or retroperitoneal fibrosis

Question 4

Where are lymph nodes located?

Answer 4

Near the groin
Axilla
Neck 
Aorta 
Porta hepatis

Question 5

What is the best landmark to identify the retroperitoneum?

Answer 5

Gerota’s fascia

Question 6

Lymph adenopathy etiology

Answer 6

Infection
Malignancy
Allergic reactions

Question 7

Typical locations of lymph adenopathy

Answer 7

Inguinal region
Neck
The mesentary *forms the sandwich sign with SMA
Renal hilum
Aorta

Question 8

Sonographic features of malignant nodes

Answer 8

Hypoechoic or anechoic

Some may be hyperechoic or calcified

Question 9

Which is the most common soft tissue tumor of the retroperitoneum?

Answer 9

Liposarcoma

Question 10

Fast growing smooth muscle malignant tumor

Answer 10

Leiomyosarcoma

Question 11

Where does Leiomyosarcoma reside?

Answer 11

In the uterus or GI tract

Grows rapidly and METS to the lungs

Question 12

What kind of lymphomas are there?

Answer 12

Hodgkin Disease: primary

Non-Hodgkin disease: secondary

Question 13

Characteristics of Hodgkin lymphoma

Answer 13

Chronic enlargement of lymph nodes
Local at the onset than later generalized
Hepatosplenomegaly
No pronounced leukocytosis (WBC not affected)
Anemia
Fever

Question 14

Sonographic appearance of Hodgkin lymphoma

Answer 14

Hypoechoic enlarged lymph nodes > 1 cm

Question 15

What is Non-Hodgkin’s disease lymphoma?

Answer 15

Secondary lymphoma
Anything other than Hodgkin's disease
Mets
Primary tumor spreads to lymphatics
Lymphatic dissemination
Common primary cancer
Testicular cancer 
Breast cancer
Lung cancer
Skin cancer

Question 16

Sonographic findings of Non-Hodgekin’s lymphoma

Answer 16

Floating aorta sign
Enlarged lymph nodes
Aorta can be displaced anteriorly

Question 17

What is retroperitoneal fibrosis?

Answer 17

Formation of fibrous tissue as a reparative or reactive. Causing abnormal thickening and scarring of connective tissue most often following injury, infection, lack of oxygen or surgery.
Proliferation of retroperitoneal connective tissue

Question 18

Causes of retroperitoneal fibrosis

Answer 18

50% idiopathic
Inflammatory
Low grade infections
Ergot medications for migraine

Question 19

Clinical presentation of retroperitoneal fibrosis

Answer 19

Abdominal pain
Back pain
Flank pain
Oliguria

Question 20

Sonographic appearance of retroperitoneal fibrosis

Answer 20

Hypoechoic mass enveloping over aorta, IVC and extends down to sacrum
MENTLE EFFECT
No aortic displacement
Smooth bordered

Question 21

Typical location of hematoma in retroperitoneum

Answer 21

Psoas muscle *most common in hemophiliacs

Around kidneys

Question 22

Causes of hematomas in retroperitoneum

Answer 22

Trauma
Surgery
Anticoagulant therapy
Bleeding problems such as hemophilia

Question 23

Clinical presentation of hematomas in retroperitoneum

Answer 23

Local pain
Transient fever
Hematocrit drop

Question 24

Sonographic findings of hematomas

Answer 24

Hypoechoic

Echogenic

Question 25

Which is the 4th most common site for METS after lungs, liver and bone?

Answer 25

Adrenal glands

Question 26

What is the “headlight sign”?

Answer 26

METS to both adrenal glands forming large, bilat, hypoechoic masses from Bronchogenic lung carcinoma