Interventional Radiology Flashcards
What are the essential skills of interventional radiologists?
Diagnostic image interpretation
Manipulation of surgical tools to navigate inside the body under image guidance
_________ uses radioactive material inside the body to see how organs or tissue are functioning or to target and destroy damaged or diseased organs or tissue
Nuclear medicine
Medical procedure that uses a real time video of the movements inside a part of the body by passing X-rays through the body over a period of time
Fluoroscopy
Imaging test that uses sound waves to make pictures of organs, tissues and other structures in the body
Ultrasound
Imaging method that combines a series of X-rays taken from different angles and uses computer processing to create cross sectional images of bones, blood vessels, organs and other soft tissues in the body
CT
Imaging technique that uses a magnetic field and computer guided radio waves to create detailed images of the organs and tissues in the body
MRI
Pre procedure work up consists of
Eval or previous imaging, patient assessment, pre-procedure checklist (labs, meds, antibiotics, consent)
Who was the first person to develop successful balloon angioplasty
Andreas Roland Grüntzig
What is the most common method used when placing a central line?
Seldinger technique- catheter insertion to obtain safe percutaneous access to vessels and hollow organs
What are the steps of the seldinger technique?
- Needle inserted through the skin into the blood vessel
- Guidewire passed into the lumen
- Needle withdrawn, leaving the guidewire
- If placing a larger cath, enlargement of insertion site is done with a scalpel
- Catheter is threaded over the guidewire and passed into the lumen
- Guidewire is withdrawn, leaving the cath in position
______________ uses fluoroscopy and X-ray images to identify and diagnose narrowing or blockages in blood vessels
angiography
The X-ray images created during angiography are called
Angiograms
Angiography is used to examine ______________in key areas of the body including:
Blood vessels
Brain, neck, heart, chest, abdomen, pelvis, legs and feet, arms and hands
Angiography is used to diagnose and treat what problems?
Bleeds, dissections, stenosis/obstruction, clots, PE, vascular malformations, and aneurysms
What is conventional catheter angiography
This is an invasive procedure that uses a catheter, X-ray guidance, and an injection of contrast to examine blood vessels for abnormalities
T or F: the use of a catheter makes is impossible to combine diagnosis and treatment in a single procedure
False. It makes this possible
What is computed tomography angiography?
A non-invasive procedure that uses IV injection of contrast into the blood vessels and CT scanning to diagnose and evaluated vessel disease
What is magnetic resonance angiography?
A non-invasive procedure that uses IV injection of contrast into the blood vessels and MRI scanning to visualize blood vessels. $$$$$$ but no ionizing radiation
Visualizes the inside of the coronary arteries to locate stenosis which could cause a heart attach.
Coronary angiography
Images the blood vessels in the lungs to eval various conditions such as PE
Pulmonary angiography
Images the renal blood vessels to detect any signs of blockage or abnormalities affecting the blood supply to the kidneys
Renal angiography
Images blood vessels however, radiopaque structures such as bones are eliminated digitally from the image, allowing for accurate depiction of the blood vessels
Digital subtraction angiography (DSA)
What are the steps of a conventional angiography procedure?
- Patient is consciously sedated and small cut is made in the skin over the artery (groin or wrist)
- Cath is inserted into the artery and is carefully guided to target area
- Contrast is injected and xrays are taken
- If needed, treatment can be done at the same time
- After the procedure the cath is removed and pressure is placed on the cut to stop bleeding.
What are systemic complications of angiography?
Allergic reaction to contrast or renal failure
What are local complications of angiography? (Puncture site and intraluminal)
Puncture site- Hematoma, pseudo-aneurysm, AV fistula
Intraluminal- subintimal dissection, thrombosis, internal bleeding
54 yo man presents to ED with a hx of high speed MVC. CT A/P shows a hepatic laceration with active bleeding from a hepatic artery branch. You have managed to stabilize his vitals but the pt is still requiring ongoing blood transfusions. What is the appropriate management?
Refer to IR for an angiogram
______________ uses fluoroscopy and X-ray to take pictures of veins in the body, mostly in the extremities, after contrast has been injected
Venography
Why is venography not used as much as angiography
It only looks at veins
Most venography is preformed in conjunction with which procedures?
IVC filters, Central venous catheters, and Renal vein sampling
Embolization
Minimally invasive procedure that blocks or closes a specific vessel
What is percutaneous transluminal angioplasty with endovascular stenting
Mechanically widening narrowed obstructed arteries and placing stents to keep the vessel open
Who places IVC filters and gets CV access
IR
What is a pharmacological agent that is used to achieve thrombolysis? What is is most commonly used for?
Tissue plasminogen activator (t-PA)
Ischemic stroke, PE, MI
Which agents act as “clot busters” by activating anti coagulation?
t-PA, Retaplase, Urokinase
Where are thrombolytics infused?
Directly into the thrombosed vessels to ensure high concentration of the drug
Relative contraindications of thrombolytics
History of GI/GU bleed
Recent thoracic/abdominal surgery
Recent trauma
Severe uncontrolled HTN
Absolute contraindications of thrombolysis
Active internal bleeding (GI/GU)
Recent intracranial hemorrhage (<2 months)
Irreversible limb ischemia
What are complications of thrombolysis
Bleeding
Distal embolization of thrombus
Established technique in the treatment of vascular stenoses due to atherosclerotic plaque formation
Balloon angioplasty / PTA
How does PTA work?
A specially designed cath with a tiny balloon is carefully guided through the artery to the blockage, then inflated to widen the opening and increase blood flow. A stent is often placed to keep the artery open. (80%)
What kind of angioplasty is done to open a narrowed or blocked artery in an extremity?
Peripheral angioplasty
What procedure is used to open blocked arteries in the heart?
Coronary angioplasty aka percutaneous coronary intervention (PCI)
What are aortic stent grafts used for?
Abdominal aortic aneurysms and thoracic aortic aneurysms
T or F: the aneurysm is not removed with aortic stent grafts, the graft is just inserted to strengthen the aorta via a catheter
True
What must you get before proceeding with an aortic stent graft? Why?
CT of the aorta for precise vessel measurement and localization of arterial branches
How does embolization offer temporary or permanent relief ?
Eliminating atypical connections between blood vessels
Closing off blood vessels that feed tumors and other abnormal growths
Stopping or preventing excessive bleeding
What are indications for embolization
Gi hemorrhage, traumatic injuries, AV malformation, cancers that cause bleeding, frequent nosebleeds, uterine fibroids
Describe an embolization procedure
Embolic agents are delivered via catheters to halt blood flow
Examples of embolic agents
Balloons, gel foam, liquid glue, liquid sclerosing agents, metallic coils, particulate agents
What are liquid sclerosing agents?
Substances that destroy tissue on contact causing abnormal blood vessels to close
What are particulate agents
Substances that permanently block small vessels
A central venous cath is used instead of a peripheral IV when treatment is expected to be longer than _____ days
5
The central venous catheter is used to deliver medications and therapies directly to the ________ allowing prompt access to the ____________
Heart
Bloodstream
For venous access the tip of the CVC is usually placed within the _________ or the _________
Superior vena cava or right atrium
When do you use a tunneled central venous catheter?
When you need >2 weeks of access
A tunneled catheter “tunnels” under the skin for _________cm to anchor it in place
8-10
Where is a tunneled cvc usually placed
Large vein in the neck
When would you use a non-tunneled central venous cath? Where is it normally placed?
If you only need <2 weeks of access
Large vein in the neck, groin, or chest
What is the most commonly used CVC and how long can it remain in place?
Peripherally inserted central catheter (PICC)
Can remain in place for up to 6 weeks
Where is a PICC line placed and where does it go?
Placed in the arm and threaded to reach the superior vena cava
Why would you use a subcutaneous implanted port (Port-A-Cath)?
Common for use in chemotherapy and it’s appropriate for long term use (at least 3 months)
What are two complications of port-a-cath placement and how do you check for them?
Pneumothorax and hemithorax
Check with CXR
What is an IVC filter and what is it used for? Who needs these?
A small metal device that is placed in the IVC. The filter helps reduced risk of PE by trapping large clots. Patients who have absolute contraindications to anticoagulants or don’t respond to them need these.
How are IVC filters placed
- Small incision in the groin or neck
- Cath inserted and moved into IVC with a collapsed filter
- The cath is removed with the filter left in place
- Filter expands and attaches itself to the IVC walls.
What are so,e complications of venous access?
Injury to the vessel, bleeding, need to repeat procedure, injury to adjacent structures, infection or sepsis
What are some non vascular interventions done by IR
Urological procedures, biliary procedures, feeding tube placement, abscess drainage, regional ontological therapy, MSK procedures
What procedure uses image guidance to place a small (pigtail) cath into the kidney to drain urine that has been backing up due to obstruction
Percutaneous Nephrostomy (PCN)
What procedure uses image guidance to place a stent into the ureter and hold it open so it can drain urine that has been backing up?
Ureteral stenting
What procedure uses image guidance to insert a needle into the liver and inject contrast directly into the bile ducts to produce images of the bile duct?
Percutaneous Transhepatic Cholangiogram
What us percutaneous cholecystostomy and who is this done for?
Placing a drainage tube to decompress the gallbladder
This is done for poor surgical candidates or high risk patients
A gastrostomy tube is placed into the ___________
Stomach
A jejunostomy tube is placed into the ____________
Jejunum (sm. Intestine)
A gastronejunostomy connects part of the __________ to the __________ to allow food to pass without going through the ____________ first.
Stomach to the jejunum
Duodenum
T or F: Feeding tubes are placed through the skin
True
What technique is used to percutaneously drain abscesses using imaging guidance
Seldinger technique
The seldinger technique is most commonly used to drain abscesses in the _______________
In the abdomen or pelvis
What procedure uses imaging guidance to place a needle into a suspicious lesion to take samples for biopsy?
Needle biopsy
What kind of Imaging is used for needle biopsies of deep structures in the chest, abdomen and pelvis?
CT guidance
What are examples of regional oncology therapy?
Radiofrequency Ablation of tumors (RFA) and Transarterial Chemoembolization (TACE)
Radiofrequency ablation is a minimally invasive procedure that uses ___________ and __________ to destroy cancer cells
Electrical energy
Heat
What are suitable tumors for RFA
Hepatoma, some hepatic metastases, lung carcinoma, bony metastases, kidney carcinoma
Transarterial chemoebolization is a minimally invasive treatment for cancer that combines ________________ and _______________ into the blood vessel that feeds cancer
Direct delivery of concentrated chemotherapy and a blocking embolic agent
Why is the potency of chemo drugs increased in chemoembolization?
The blocking agents make the cancer more susceptible to the chemo by blocking the supply of oxygen and nutrients to the tumor
What are some procedures IR does for musculoskeletal complaints?
Steroid injections for pain
Osteoid osteoma Radiofrequency ablation
Vertebroplasty
How is vertebroplasty done?
Percutaneous injection of bone cement into a vertebral body fracture to stabilize the spine and decrease pain
