IR Flashcards
1
Q
Indications for transarterial thrombolysis
A
- acute (<14 days) native arterial thrombosis
- acute (<14days) graft thrombosis
- acute emboli
- NOTE: Chronic occlusion is probably better served by surgical correction.
2
Q
Dropped emboli post transarterial thrombolysis
A
- After the 12-hour infusion of reteplase, however, the runoff has been adversely affected with the evidence of abrupt cutoff of the dominant runoff vessels, the peroneal and anterior tibial arteries, suggesting “dropped” emboli from the graft lysis.
- When this happens, need to continue with transcatheter thrombolysis.
3
Q
FNH feeding vessel
A
- FNH is well-circumscribed, hypervascular
- feeding vessels are enlarged, and usually in the periphery
- no AV shunting, no pooling or puddling of contrast
4
Q
Transplant renal artery stenosis
A
Delayed time-to-peak, retention of contrast
Undistinguishable from
- RAS
- ATN
- Rejection
5
Q
When to treat splenic artery aneurysm
A
- Ruptured and symptomatic SAAs
- In pregnant women or women of childbearing age
- Patients with portal hypertension or who undergo liver transplantation
- Enlarging aneurysms
- Aneurysms 2.5–3 cm or more in diameter
6
Q
Splenic artery pseudoaneurysm from pancreatitis
A
- Soft tissue mass on CT with an “onion-layered” pattern and with the adjacent area that enhances similar to the aorta is a classic CT pattern for a partially thrombosed pseudoaneurysm
- Vascular injury from pancreatitis
- venous thrombosis/occlusion
- arterial pseudoaneurysm
- Rx for splenic artery pseudoaneurysm - embolization
- need to occlude the vessel both proximal and distal to its origin
- proximal embolization alone would allow perfusion to the pseudoaneurysm through collateral pathways
7
Q
IR Rx of traumatic thoracic duct transectionn
A
- lymphangiography
- thoracic duct embolization
8
Q
Hepatic tumor chemoembolization
A
- High density contrast material - Lipoidol (Ethiodol: brandname is US)
- poppyseed oil
- radiodense contrast material
9
Q
Hepatic subcapsular hematoma
A
- Liver subcapsular hematomas often occur when the parenchyma of the liver is disrupted by blunt trauma, but Glisson’s (liver) capsule remains intact.
- It is usually secondary to hepatic arterial hemorrhage.
- Typically, the finding is a lenticular-shaped low-density area beneath the liver capsule that may compress the hepatic parenchyma.
10
Q
IR Rx for biliary stenosis
A
- PTC (percutaneous transhepatic cholangiogram) should be performed to delineate biliary anatomy
- Prophylactic antibiotics should be give 1 hour before the procedure to prevent biliary sepsis.
- A 10-Fr or larger internal/external biliary drainage catheter should be placed across the stricture and left to drain bile into the small bowel.
- If the anastomotic stricture cannot be transversed at the initial setting, an external drainage catheter should be placed and a second attempt made a day or two later.
- Internal drainage is important to avoid loss of bile salts and to secure the drainage catheter*.
- Percutaneous balloon dilatation of benign biliary strictures is another option. Following dilatation, a large (12-Fr or greater) biliary catheter should be left across the stricture to prevent restenosis. Patients should return every 2-3 months for routine biliary catheter exchanges and repeated angioplasty if necessary.
11
Q
IR Rx for biliary leak from cystic duct
A
- PTC
- Percutaneous biliary drainage until the cystic duct heals on its own
12
Q
Post renal transplant lymphocele
A
- Present with swelling over the transplant, unilateral leg edema secondary to iliac vein compression, or increased creatinine and hydronephrosis secondary to ureteral compression.
- Diagnosis of lymphoceles can be confirmed by simple aspiration.
- high protein content
- creatinine concentration equal to that of the serum
- The treatment of lymphocele in the acute phase includes percutaneous drainage and monitoring.
- In cases resistant to this therapy, sclerosis of the cyst cavity can be considered (using povidone-iodine or tetracycline).
- The definitive and preferred therapy is surgical unroofing of the lymphocele wall to allow drainage into the peritoneal cavity (peritoneal window).
- It should be noted that small asymptomatic lymphoceles don’t require treatment.
13
Q
Traumatic ICA dissection
A
- Risk of thrombosis and embolization
- Rx - anticoagulation +/- antiplatelet
- May use endovascular stent
14
Q
MR appearance of fibroids
A
- iso to hypo intense on T1 and T2
- enhance on post gad images
- if no enhancement - spontaneous infarct
- Rx - uterine artery embolization
15
Q
Percutaneous cholecystostomy
A
- Indications: calculous and calculous cholecystitis, access for stone fragmentation and removal and sometimes for decompression of both the gallbladder and the biliary system if a transhepatic route is not feasible.
- Access to the gallbladder is frequently performed using ultrasound guidance.
- Access routes include transhepatic and subhepatic
- For the transhepatic route, advantages include an easily visible window through the liver with ultrasound guidance, the tamponade effect of the intervening liver for catheter placement, a more readily established tract between the gallbladder and the skin, and entry to the gallbladder at a fixed point. Disadvantages include liver injury from placing a catheter through the parenchyma.
- The single most notable advantage to a subhepatic or transperitoneal approach is the avoidance of traversing the liver and all its potential complications. A major disadvantage of the subhepatic or transperitoneal approach is the possibility of gallbladder laceration with bile peritonitis secondary to the mobility of this portion of the gallbladder.
- In general, the catheter must remain in place for six weeks to allow for the establishment of a connecting tract.
- Inflammation of the gallbladder must resolve and the patency of the cystic duct must be demonstrated. The catheter can then be removed after an established tract between the gallbladder and the skin has been demonstrated as well.
16
Q
Primary Subclavian-Axillary Vein Thrombosis
(Paget-Schroetter Syndrome)
A
- Primary SAVT is idiopathic or related to physical activity or arm positioning;
- All other causes (usually central venous catheters) are referred to as secondary SAVT.
- Primary SAVT accounts for less than 2% of all cases of deep vein thrombosis and is frequently associated with an extrinsic compression of the subclavian-axillary vein due to narrowing of the costoclavicular space by bony and/or soft-tissue structures.
- In the majority of cases, the clinical presentation is that of a young, active, healthy male who rapidly develops swelling of his dominant arm.
17
Q
Iliac artery occlusion
A
- Iliac artery occlusion may be acute or chronic
- The presence of well-developed collaterals –> chronic occlusion
- Lumbar artery is an important collateral
*
18
Q
Carcinoid tumor
A
- CT - mesenteric mass, radiating vessels, dysplastic reaction, mesentery being “pulled in” towards the mass; 70% has calcifiations
- NOTE: fibrosing mesenteritis can have a very similar appearance
- Angiography - primary carcinoid tumor and carcinoid metastases are very different!
- carcinoid tumor - avascular; with associated arterial and venous occlusion
- liver carcinoid metastases - hypervascular like any other neuroendocrine tumors
19
Q
Vertebroplasty
A
- Indications: compression fractures and clear association of pain onset and fracture, painful tumor (including metastases, hemangiomas, and myeloma), and occasionally traumatic fractures.
- Contraindications: coagulopathy, inability to lie prone, unclear etiology of back pain, severe compression fracture, or comminuted burst fracture. There is a relative contraindication if the fracture line extends to the posterior wall of the vertebral body or if there is fear of cement going into the canal.
20
Q
Hilar Cholangiocarcinoma
Klatskin tumor
A
- Risk factors: PSC, choledochal cysts, familial polyposis, congenital hepatic fibrosis, and infection with the liver fluke Clonorchis sinensis.
- CT: delayed enhancement of tumor
- Rx: perc external/internal drain; if life expectancy < 1 year, metallic stent can be placed
21
Q
Renal angiomyolipoma
A
- CT/MR - fat content
- Angiography - enlarged, distorted feeding vessels, may contain aneurysm
- NOTE: hypervascular AML may be fat poor and do not have fat content visible
- can be differentiated from RCC by the lack of calcifications
- >4cm is usually the threshold for Rx
22
Q
Hypothenar hammer syndrome
A
- An abnormality of the ulnar artery caused by repetitive, blunt trauma to the hypothenar area.
- HHS is most prevalent in men with occupations that require repetitive hammer-like motion
- The mechanism of injury is repetitive injury of this arterial segment as it courses around the hamate bone.
- Characteristic “corkscrew” or “beaded” appearance to the effected artery, and the segment can serve as a source of emboli to the digital arteries.
- Other angiographic findings include aneurysm and thrombosis of the ulnar artery.
23
Q
Budd-Chiari syndrome
A
- Hepatic vein or IVC occlusion or stenosis.
- The syndrome is idiopathic in 2/3 of cases. Maybe associated with
- OCP, neoplasms, congenital disorders, polycythemia rubra vera, chronic leukemia or trauma.
- Hepatic venoocclusive disease - Jamaican toxic bush tea
- CT - nutmeg liver
- NM (Tc99m sulfur colloid)- hot caudate lobe (separate venous drainage into IVC)
- Angio - “spider web appearance” of intrahepatic collateral veins
24
Q
Leriche syndrome
A
- chronic occlusion of the abdominal aorta
- form collateral pathways
- triad
- buttock and thigh claudication
- absent femoral pulses
- impotence
25
Q
Branches of posterior division of the internal iliac artery
A
- iliolumbar artery
- superior gluteal artery
- lateral sacral artery
26
Q
Popliteal artery occlusion post knee posterior dislocation
A
- thrombogenic response post intimal injury
*
27
Q
Popliteal artery entrapment syndrome
A
Can be elicited by plantar flexion of foot
28
Q
Mesenteric ischemia
A
Classification of mesenteric ischemia
- occlusive
- embolus
- thrombosis
- non-occlusive
- low flow status - sepsis, shock, heart failure
29
Q
Fibrin sheath formation
A
- Fibrin is thought to begin forming within hours at the site of catheter insertion. It is composed of fibronectin, laminin, collagen and immunoglobulins.
- Fibrin sheath can form a tail or flap extending from the catheter tip and is responsible for persistent withdrawal occlusion.
- Upon infusion, this flap opens and allows fluid flow, while upon aspiration, this flap is pulled over the catheter lumen occluding the backflow of blood.
- Treatment Options include intraluminal thrombolytic infusion, fibrin sheath stripping using a snare, and catheter exchange over a guidewire.
30
Q
Most common cause of colonic bleed?
A
- diverticular disease
- angiodysplasia
31
Q
Angiodysplasia
A
- common cause of colonic bleeding
- more properly termed “telangiectasia”, as angiodysplasias are dilatations of normal, pre-existing blood vessels
- >60 yo
- almost always occur in cecum and right colon
- colonoscopy - the only way to clinical Dx
- angiography
- a densely opacified tuft or tangle of vessels best seen in the arterial phase
- an early-filling vein that can either be seen in the late arterial phase or early venous phase
- extravasation of contrast into the colon
- Rx: endovascular vasopressin injection and embolization; surgical resection
32
Q
Page kidney
A
- renin-dependent hypertension due to renal ischemia caused by external renal compression without evidence of renal artery stenosis
- causes of renal compression
- Most commonly, trauma causing either subcapsular or perinephric hematoma.
- intrarenal or splenic cyst
- renal rhabdomyosarcoma
- infectious urinoma
- pararenal lymphatic cysts
- peritransplant hematoma
- retroperitoneal paraganglioma
- Rx: Observation with blood pressure therapy; Percutaneous drainage; Capsulectomy; Nephrectomy.
33
Q
Venous rupture following angioplasty of hemodialysis graft stenosis
Treatment options
A
- (1) manual compression of the injured area
- (2) reinflation of the angioplasty balloon across the site of injury to provide endovascular tamponade
- (3) deployment of an endovascular stent across the damaged vascular segment
- If all of these methods fail to control bleeding from the rupture site than the final alternative may be to occlude the hemodialysis graft
34
Q
Right sided aortic arch
A
2 patterns
- most common branching pattern - aberrant left subclavian artery
- travels posterior to the esophagus
- dysphagia lusoria
- 12% risk of congenital heart disease
- second most common branching pattern - mirror image
- 98% congenital heart disease
35
Q
Adventitial cystic disease
A
- an uncommon cause of intermittent claudication
- mucin-filled cysts originate within the arterial adventitia and progressively enlarge, leading to extrinsic compression and focal stenosis and even occlusion of affected vessel
- most common occurs in popliteal artery
- typically young male
- Rx: medical, percutaneous, surgical
36
Q
Median arcuate ligament syndrome
A
- gold standard - lateral angiography
- exacerbation of stenosis on expiration
- Rx: surgery; endovascular is less long-lasting
37
Q
Cavernous venous malformation
A
- mature age, lack AV communication
- lesion is more extensive on venogram than on MRI
- NOTE: capillary hemangioma on the other hand, will involute as the baby grows
- characteristic Dx findings are
- dilated venous spaces that fill slowly on a diagnostic venogram, and late in the late phase of an arteriogram
- poor communication with normal venous channels
- no arterial abnormalities
- calcified phleboliths
- lesions usually more extensive on venogram than on CT/MR
- Rx: direct puncture of the venous malformation, and injection of sclerosant
38
Q
Portal vein thrombosis
A
- Etiologies for portal vein thrombosis
- idiopathic
- malignancy - HCC, pancreatic carcinoma, metastatic carcinoma
- coagulable state
- cirrhosis
- pancreatitis
- sepsis
- Rx: systemic anticoagulation, catheter-directed thrombolysis
- Complications - can lead to pre-sinosoidal portal hypertension
39
Q
Pancreatic pseudocyst
A
- DDx
- pancreatic pseudocyst
- pancreatic/peripancreatic abscess
- pancreatic cystic neoplasm
- enteric or mesenteric duplication cyst
- lymphangioma
- As the fluid can track a variety of places before formation of a wall, pseudocysts can be identified in the paracolic gutter, the pararenal spaces, the lesser sac, or even the mediastinum
- Indications for drainage
- compression of adjacent organs, superimposed infection, significant pain
- Rx
- percuataneous drainage if a safe route is available
- transgastric drainage
- surgical - cyst-gastrostomy
- If output is high through the drainage tube
- may have developed a pancreatic ductal fistula
- Rx - TPN, bowel rest, and octreotide to decrease pancratic secretions to allow fistula to heal
- when puncturing the stomach, try to avoid the lesser and greater curvatures
- to avoid gastric and gastroepiploic areries, respectively
40
Q
Splenic artery aneurysm
A
- 60% of all splanchnic artery aneurysm
- causes - medial degeneration and fibrodysplasia, portal hypertension, hormone/pregnancies, infection, pancreatitis
- majority are true aneurysms
- rupture rate 2%
- NOTE: most of splenic artery aneurysms discovered during pregnancy rupture! 95%! high maternal and fetal mortality!
- Rx recommonded if
- >2cm
- growing
- symptomatic
- pragnant
- if associated with inflammation/infection - pseudoaneurysm
- Percutaneous embolization
- Occlusion the splenic artery itself, as close as possible to the splenic artery aneurysm, is preferable and safer in comparison to the more risky aneurysmal cavity embolization
- also need embolization of all outflow tracts to prevent retrograde collateral flow into the aneurysm
- Post-embolization syndrome: LUQ pain, fever. Rarely, splenic infarct, with or without abscess formation, can occur after splenic artery embolization
41
Q
Hepatocellular carcinoma
A
- can be solitary, multicentric, or diffuse
- angiographic findings
- enlarged arterial feeders
- neovascularity
- vascular lakes and puddles
- dense tumor stain
- arterial-portal shunting
- invasion of hepatic veins and bile ducts
- NOTE: hepatic adenoma and FNH may also show enlarged feeding vessels and neovascularity, but no tumor staining or venous puddling/lake!
42
Q
A
- white arrow - left main renal artery
- yellow arrow - anterior and posterior division
- blue arrow - segmental artery
- green arrow - interlobar artery
- dividing further - arcuate artery
- smallest branch - interlobular artery
43
Q
Polyarteritis nodosa
A
- panarteritis of small to medium sized arteries
- multiple foci of fibrinoid necrosis beginning in the media of the vessels with subsequent inflammation spreading to involve with intimia and adventitia
- periarterial inflammation and destruction of the elastic lamina that leads to the formation of small aneurysms, local thrombosis, and vessel rupture
- involvement
- renal 80-100%
- cardiac 70%
- liver 40-60%
- gastrointestinal 30-50%
- angiography findings
- multiple small aneurysms - 100% specific!
- stretching and attenuation of the peripheral intrarenal vessels
- decrease number of vessels from multiple thromboses
- patchy nephrograms secondary to small subsegmental infarcts
44
Q
Chronic mesenteric ischemia
A
- classic surgical teaching requires at least 2 of 3 mesenteric vessels to be compromised by a stenosis or occlusion
- not always the case though
- median arcuate ligament syndrome - only celiac is compromised but symptomatic
- some patients with 3 vessel occlusion but asymptomatic from good collaterals
45
Q
Subclavian steal syndrome
A
- subclavian artery stenosis or obstruction near its origin, with reversal of flow in the ipsilateral vertebral artery at the expense of the cerebral circulation
- occlusion has to be more proximal to the takeoff of the vertebral artery
- male:female = 3:1
- vertebrobasilar insufficiency - syncopal episodes, particularly upon exercising the ischemic arm, headaches, vertigo, and ataxia. Additionally, there may be signs of left arm claudication.
*
46
Q
AV fistulas for hemodialysis
A
- Several types
- direct arteriovenous fistulas
- synthetic and nonsynthetic interposition grafts
- polytetrafluoroethylene
- (PTFE)
- stenosis of arterial inflow is very rare
- more often on the venous side
47
Q
Contrast agent choice
A
- if worried about esophageal perforation
- use Gastrografin/soluble contrast agent
- barium can cause mediastinitis
- if worried about aspiration
- use Barium
- Barium is well tolerated in the airways and is used in bronchography
- Gastrografin will cause pulmonary edema/inflammatory pneuomonitis
48
Q
A
Since the liver receives about 75% of its blood supply from the portal vein, unless the patient has underlying severe liver disease, hepatic artery embolization is rarely complicated by liver failure.
49
Q
Rasmussen aneurysm
TB pulmonary artery mycotic aneurysm
A
- mass hemoptysis > 300cc/24hours
- most common cause - bleeding from bronchial arteries
- percutaneous transcatheter embo with balloon or coils
50
Q
Caroli’s disease
Choledochal cyst variant type V
A
- choledochal cyst type V
- autosomal recessive
- cystic dilatation of the intrahepatic biliary ducts is the hallmark of the disease, but the extrahepatic biliary tree may also be involved
- may be associated with cirrhosis, portal hypertension, or congenital hepatic fibrosis
- complications
- pain, infection, bacteremia and/or sepsis, and stone formation
- Rx: PTC drainage, stent placement in CBD, partial hepatectomy (if only part of the liver is involved)
108
Q
A
- Type 1B choledochal cyst
- Note the pancreatic duct arising from the common bile duct, and long “common channel” of the CBD distal to the insertion of the pancreatic duct
111
Q
A
persistent sciatic artery
with aneurysm formation
113
Q
A
- abnormal medial course of the popliteal arteries
- occlusion upon plantar flexion of feet
120
Q
Types of choledochal cysts
A
- Type I - most common (80-90%); saccular or fusiform dilatation of the CBD; normal IH ducts
- Type II - isolated diverticulum of the CBD
- Type III - also called choledochocele; arise from dilatation of the duodenal portion of CBD or where pancreatic duct meets
- Type IV - intra and extra-hepatic duct dilatation
- Type V - also called Caroli’s disease; cystic dilatation of the intrahepatic ducts only
