Body Imaging:

 

 

Hepatic Protocol CT:

 

liver segments on rad assistant

 

What is it:

multiphasic CT with post contrast imaging to further characterize hepatic lesion to exclude mainly HCC

 

Indications:

suspected HCC

characterization of unknown hepatic lesion

Probable hemangioma

 

Technique:

 

early arterial

portal venous

and +/- delayed

+/- noncontrast scan

 

List of possible diagnoses:

 

Malignant Focal Lesions to exclude:
HCC*** the major one- in cirrhotics

Fibrolammellar HCC- younger patients without cirrhosis, has central scar

Biliary tract cancer AKA cholangiocarcinoma or gallbladder Ca

Mets:  Neuroendocrine, renal cell, melanoma

 

Benign Focal Lesions to try to confirm:

Focal Nodular Hyperplasia (FNH):  central enhancing scar

Hemangioma- extremely common, peripheral nodular enhancement, can be huge and mimic HCC
Adenoma- common in woman on OCs, also men taking steroid, can hemorrahge

Cyst - no enhacneent, fluid attenuation, think about possible biliary cystadenoma could look similar

 

Cystic lesions that aren't simple cysts:

Abscess:  periphearl enhacement

Echinococcal cyst:  internal membranes

Work in Progress****

 

Hypervascular Liver Lesion DDX (the H's):

Hepatoma / HCC

Hepatic Adenoma

Hemangioma

Hypervasc met

FN[H]

 

 

 

Renal Protocol CT:

Short list of diagnoses to make on Renal Protocol CT:

 

Noncontrast Phase Diagnoses of Exclusion:

Stone:  obstructing or nonobstructing

Hyperdense cyst:  according to studies, diagnostic at HU >65-70, shouldn't enhance

 

Nephrographic Phase Diagnoses of Exclusion:

RCC- enhancing mass, first thing to exclude**

AML- contains macro fat

Onctocytoma- can't tell its not RCC

Renal Lymphoma- can be masslike or infiltrative

AVM- enhances to same degree as artery

Infection- can occasionally look like focal mass

 

Cystic Masses to exclude:
Cystic RCC

Multilocular Cystic Nephroma

 

Excretion Phase Diagnoses of Exclusion:

TCC:  transitional cell Ca- showing up as filling defect in collecting system, can be multiple filling defects in up to 40% of cases, also check bladder for SYNCHRONOUS lesion

polpys are benign lesions, IMO any filling defect could be suspicous unless looks classicly benign

 

DDx of ureteral filling defect:

1.  TCC

2.  Calc

3.  Blood clot

4.  Malacoplakia/ leukoplakia

5.  Infectious debris

6.  sloughed renal papilla

7.  benign polyp

 

Other things:

UPJ obstruction- dilated pelvis, normal ureter, multiple causes

ureterocele:  cystic diltation of the ureter, check bladder

 

Bladder lesions:

make sure to note that bladder is not well eval because not usually distended with contrast, also cystoscopy is better test

 

 

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Spleen lesions:

 

wanderings pleen

can torse, twist vascular pedicle

r/o infarction

showed case of spleen in the pelvis

showed case of infarcted spleen with twisted vasc pedicle

 

accessory spleen

who cares.  really who cares.  ok it could mimc a mass in the pancreatic tail (SM has seen 6 of these misdiag as pancreatic neoplasm

 

polysplenia

think about ambiguous situs

assoc with high mortality?  not sure why

see lots of small spleens on the R side

 

Benign stuff:

 

abscess- usu in immunosuppresed pts

usually solitary and unilocular

showing low attenuation of the entire spleen as abscess

 

multiple small lesions:

think microabscesses, just like liver, could be fungal

again think immunocomp

 

think about pseudoaneurysm formation after infection with destruction of the vessel wall within spleen, just like pancreatitis

 

ileocecal wall thickening think about TB? acc to SM

 

low attenuation lymph nodes think about TB or MAI

 

hydatid disease is rare accord to SM with 30 yrs exp never seen a case (in the spleen that is)

 

can see these in the liver.  mother daughter cysts

 

Sarcoid:  very common lesion according to SM.  Can be seen in the spleen.  

looks like multiple hypodense lesions in spleen, acc to SM dont need to remove spleen

 

Sarcoid in abd:  lymphadenpathy and liver lesiosn**

 

Splenosis usually happens after trauma, pretty common, not usu clincally sig.  can use Tech99 to diagnose

 

Splenic infarct***

super common

portal htn can cause venous infarction

pts have LUQ pain

usually not clinically evident- SM likes to make this diag in the ER

may not be a classic wedge shaped thing

these can get superinfected**

 

Sicka cell

get splenomeg

then autoinfarct

often see a small calc spleen

ice diag to make or to know a pt has sicka cell if not already known

 

Splenomegaly

why?

portal htn

infiltration ?gauchers

heme disease of any type

infection / mono

 

CLL- HUGE SPLEEN 

 

Gamna Gandy bodies seen in cirrhosis in the spleen

these bloom on in phase imaging

 

showing decreased signal in the spleen due to iron deposition

think about hemosiderosis

this could be due to multiple transfusion

 

hemochromatosis can lead to cirrhosis and then HCC*** and DOES NOT INVOLVE SPLEEN***

1* hemochromatosis does not involve the spleen acc to SM***

 

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Cysts:

 

true cysts have cellular lining

false cysts have no lining (no epithelium)

 

splenic hamartoma, could show up as small cystic looking lesion in the spleen, i swear i saw this biopsied on IR once or read a case that was

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hemangioma

similar to liver hamangioma

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lymphangioma can be seen in the spleen- cystic looking lesion**

 

angiosarcoma- very rare per SM

 

lymphoma- looks like anything

mass, inftration, doesn't really enhance

nasty looking big a** spleen - think lymphoma**

 

Melanoma mets to spleen****** i dont know why though