These are 4 cases seen on my month on radiology chosen for teaching value: Endoleak, Aortic Dissection, Pneumobilia, Portal venous gas. Download for complete transitions & notes.
2. Case 1: How to Evaluate for Endoleak?
https://www.aafp.org/afp/2002/0415/p1565.html
3. Case 1: RS
• 82 M 2017
• 2017 - P/W asymp.
Infrarenal AAA, 5.5 cm
• Aortobi-iliac
endovascular
aneurysm repair using
a Gore stent graft
https://surgery.ucsf.edu/conditions--procedures/endovascular-aneurysm-repair.aspx
4. Case 1: Imaging
• Regular check-ups for leak
• Check HU to look for extravasation
• 07/2018
• “no CTA evidence of endoleak on
arterial-phase imaging, but evaluation
for potential endoleak is limited…in
the absence of delayed-phase
imaging”
• 2/12/19
• Got repeat CTA with delayed films
• Why is delayed phase so important?
11. Case 1: What’s Next?
• Evidence of Type II
• Without an increase in sac size
• Asymptomatic
• Observe and F/U in 3-6 mo
12. Case 1: Takeaways
• Type ____ Endoleaks are the most common
• Retrograde flow usually arises from ______
• Requires what kind of CT imaging?
13. Case 2: JS
• 81 yo F with Hx of HTN and Afib
• P/W with sudden CP radiating to the back, stable
• Study?
• CT Chest, Abdomen, Pelvis W/ & W/O Contrast
14. Case 2: Acute Aortic Syndrome
1. Most Common
2. Shearing forces False
Lumen & Intimal Flap
3. +/- Enhancing (Thrombus)
1. Rupture of vaso vasorum in
media
2. Overlooked because it’s non-
enhancing
3. Delayed mortality up to 25%
1. Ulceration of plaque
2. Outpouchings of contrast
3. Often multiple, rarely rupture
Rx
15. Case 2: AAS Imaging
• http://www.radiologyassistant.nl/en/p441baa8530e86/thoracic-aorta-the-acute-aortic-syndrome.html
19. Case 3: From Imaging Note
VASCULAR:
• Type A intramural hematoma … extends from the aortic … all the way
through the abdominal aorta
• At the level of the diaphragmatic hiatus, there is a small penetrating
ulcer … allows contrast to pass into the mural wall.
• No dissection flap is identified.
20. Case 2: Findings & F/U
• Type A intramural
hematoma
• Ascending aortic
& Transverse
hemi-arch
replacement
• Known residual
descending/abd
dissection
• Penetrating ulcer
at diaphragmatic
hernia Rx
21. Case 2: Takeaways
• Have to check for all 3 types of acute aortic syndromes
• Variability in management and prognoses
• Requires attention to spiraling, enhancement, calcifications, flap, etc
22. Case 3 & 4: Air in the Liver
• Pneumobilia vs. Portal Vein Gas
23. Case 3: AH
• 60 yo M
• Hx of acute cholecystitis, deferred surgery
• P/W generalized abdominal pain with N&V
• CT Abd, Pelvis with contrast
32. Case 3: Discussion
• Pneumobilia is air in the
biliary tree
• Air stays Central
• Etiology often benign
• Recent biliary
instrumentation, ERCP
• Gallstone ileus
• DDx is limited but includes…
• Portal venous gas
https://radiopaedia.org/articles/pneumobilia?lang=us
33. Case 4: DH
• 80 yo M with Hx of vascular disease
• P/W blood-tinged diarrhea, LLQ pain
• Had N/V & not been able to eat or drink AKI
• CT Abdomen, Pelvis without contrast
34.
35.
36.
37. How does gas reach the liver?
Ischemia causes
necrosis of
bowel wall
Bacteria releases
gas into bowel
wall & vessels
Gas travels
through portal
vein system
40. Case 4: Take-away
• Portal venous gas
• Usually reaches the
Periphery of the liver
• Very concerning for
intestinal ischemia
41. Summary
1. Endoleak Evaluation with CTA Delayed Phase Imaging
2. 3 Types of Acute Aortic Syndromes
3. Two Cases of Air in the Liver
Editor's Notes
https://www.aafp.org/afp/2002/0415/p1565.html
Coronal CT angio & axial CT with con of AAA
Point out renals and thrombus
Left: FIGURE 5A.
Reconstructed computed tomographic angiogram in the frontal projection demonstrating the bilobed infrarenal aortic aneurysm (arrow heads). The renal arteries are well visualized (small arrows), revealing a severe stenosis of the proximal right renal artery (outline arrow) and the proximity of the aneurysm neck to the renal arteries. The relationship of the aneurysm to the iliac arteries and the aneurysmal dilatation of the right common iliac artery (outline arrow head) are also well displayed.
https://surgery.ucsf.edu/conditions--procedures/endovascular-aneurysm-repair.aspx
Goal is to dec blood flow to the aneurysmal parts and prevent rupture
If you see something in the arterial phase, don’t know if it’s acute enhancement in the thrombus
Delayed phase – looking for change in thrombosed portion, that it’s not a chronic calcification
Type II endoleaks account for approximately 40% of all endoleaks encountered in clinical practice and are the most common [3]. They occur when there is retrograde flow of blood into the aneurysm sac via an excluded aortic branch, most commonly the inferior mesenteric artery or a lumbar artery. Many type II endoleaks close spontaneously over time [3]
https://www.ajronline.org/doi/pdf/10.2214/AJR.08.1593
At level of renal arteries, no graft – infrarenal
Graft starts
Bi-iliac graft, see it as it splits
Can also see the anuerysm
Look for difference in enhancement
Can see possible lumbar artery feeding into it
II
Lumbar, IMA arteries
CTA with delayed phase imaging
What are we thinking of here? What’s the best study to get?
Ok so ‘ve always thought of classical AD, but have to know about other 2
Clinically presentation and Tx can be very similar with different pathophysiologies and different prognoses
Often you can have multiple types have to look for all 3
3 Types of Dissections
Small subtle IMH often not seen with contrast
IMH – why you get non-contrast
http://www.radiologyassistant.nl/en/p441baa8530e86/thoracic-aorta-the-acute-aortic-syndrome.html#i441d7719eda9d
Many details about calcification, spiraling, etc I’m not getting into
Always have to check where the dissection is in relation to LSCA
Can start to see a little at start of aortic outlet
Can see it clearly in the descending
Can see
No intimal flap or false lumen (not classic AD)
No fenestration (not PAU)
Not fully enhancining – not aneurysm
Still have IMH
Now also have PAU
Unless it involves aortic root, may also be conservative mgmt
Gall bladder wall thickening
Air in the GB
1. Inflammation of the gallbladder compatible with chronic cholecystitis with a
definite fistula to the adjacent duodenum.
Minimal fluid is present in the
gallbladder fossa and tracks around the anterior surface of the liver. Minimal
associated pneumobilia. No biliary obstruction.
Small amount of pneumbilia
1. Inflammation of the gallbladder compatible with chronic cholecystitis with a
definite fistula to the adjacent duodenum. Minimal fluid is present in the
gallbladder fossa and tracks around the anterior surface of the liver. Minimal
associated pneumobilia. No biliary obstruction.
Fistula
2. Gallstone ileus. Multiple prominent dilated loops of mid jejunum. Large 31 x
16 mm calculus obstructs the bowel on image 73 series 5. Administered oral
contrast material shows transit to the colon indicating incomplete obstruction.
2. Gallstone ileus. Multiple prominent dilated loops of mid jejunum. Large 31 x
16 mm calculus obstructs the bowel on image 73 series 5. Administered oral
contrast material shows transit to the colon indicating incomplete obstruction.
Why does it localize centrally?
Image credit: https://jonbarron.org/article/healing-liver-and-gallbladder
Intestinal ischemia pneumatosis, intestinalis
Wall thickening
Air, subserosal
Incidental umbilical hernia w/o evidence of SBO
. Extensive portal venous gas with multiple distal small bowel loops which
demonstrate wall thickening and scattered pneumatosis concerning for bowel ischemia. There is a loop of small bowel which protrudes into an umbilical
hernia without upstream dilatation or surrounding soft tissue stranding to
suggest current or recent obstruction.
Bubbles of Air in subserosa eventually forms ring around stool