Diagnostic radiology - Interventional radiology Flashcards
Indication for intervention radiology in vascular diseases?
- Aortic aneurysms
- Pulmonary embolism
- Vascular access
- Varicose veins
- Vascular malformations
- Peripheral artery disease
3 procedures for oncology treatment or assessment by IR?
- Guided biopsy
- Percutaneous Ablation: Curative treatment for small tumors
- Endovascular embolization: Palliative/ curative treatment for multiple tumours
5 procedures for GI tract disease treatment by IR
Abscess drainage Treat complications of transplant Biliary stenting and biliary drainage Liver cancer Nutritional support/ Gastrostomies
5 neurovascular conditions treated by IR
Acute ischemic stroke Venous thrombosis Aneurysms AVM Arteriovenous fistulae
5 genitourinary conditions treated by IR
Stones BPH Fibroids Nephrostomies Renal cancer
4 procedures for MSS treatment by IR
Vertebroplasty/ kyphoplasty
Spinal injections
Joint injections
Biopsies and tumor ablation
3 advantages of IR over conventional surgery
More precise = safer (avoid
hitting/injuring major vessels, organs)
Most done under local anaesthesia = suitable for patients who may not be surgical candidates
Reduced hospital stay (some can be done
as day case), faster recovery
Provide additional diagnostic information
3 limitations of IR
- Ionizing radiation (some)
- Not universally applicable (e.g. huge lesions)
- Emerging techniques with less clinical evidence
Function of Image guided biopsy?
Examples?
Obtain sample to help Dx: Microscopy, biochemistry, Histology or Cytology tests
Fluid or solid aspiration or drainage
- Fine Needle Aspiration for cytology
- Core biopsy for histology
- Trephine biopsy for bone marrow
2 modalities of image guidance for biopsy?
give examples of procedures
- US (e.g. endobiliary forceps biopsy, transrectal prostate biopsy)
- CT (e.g. adrenal venous sampling, transjugular liver biopsy)
Advantage of CT guided biopsy over US?
- Visualize structures without obstruction, wider field of view (US cannot penetrate bone, overlying fat, fluid …etc)
-
Indication for CT-guided biopsy?
Thorax
Abdomen: pancreas, adrenal gland, bowel, retroperitoneal masses (clearer visualization than US due to overlying bowel and fat)
Neck masses not seen on US
Complications for CT guided biopsy
1) Vascular damage:
- Bleed (e.g. pararenal hematoma)
- Arteriovenous fistulas (e.g. post renal biopsy)
- Pseudoaneurysm
2) Infection
3) Organ injury:
e. g. Puncture normal pancreas = pancreatitis
e. g. Lung biopsy: Pneumothorax, Haemoptysis
4) Needle tract tumour seeding (rare)
4 modalities of image guidance for percutaneous drainage?
fluoroscopy, ultrasound, CT and MRI
Which approach is best for Image guided pelvic abscess drainage?
- Posterior approach through gluteal muscle
- Insert catheter for continuous abscess drainage
Complications of image guided drainage of liver (or other) abscess?
Sepsis (pus release to blood/ surrounding)
Hemorrhage (needle hits blood vessel)
Death (secondary to sepsis or hemorrhage)
Hydatid cysts:
- CT findings?
- IR treatment?
CT findings:
Well-defined, hypoattenuating, with distinguishable wall
Wall calcification (50%)
Daughter cysts (75%)
Percutaneous drainage:
Pretreatment with metronidazole
Instill sclerosing agent
Outline a simplified procedure of Percutaneous transhepatic biliary drainage
- Needle punctures bile duct through the skin and liver
(e. g. with dilated ducts) - Inject contrast material to opacify the bile ducts using fluoroscopy
- Pass a guide wire through the needle into the bile ducts and maneuver into the duodenum
- Pass a drainage catheter (with side holes) over the guide wire into the duodenum through the obstruction
- Withdraw the guide wire
Indications for Percutaneous transhepatic biliary drainage
relieves / drains biliary obstruction:
- obstructive jaundice/ malignancy biliary obstruction- use stenting
- biliary sepsis
- Post-operative bile leaks
- Before surgery to decompress the biliary system
- During ablation to protect biliary tree
2 main types of Percutaneous drainage
1 precautionary procedure for both
Percutaneous transhepatic biliary drainage
Percutaneous nephrostomy
Antibiotic coverage for both
4 acute complications of Percutaneous transhepatic biliary drainage
Bleeding into biliary system/ post-PTBD bleed (most
common) = hypotensive
Infection – septic shock
Pancreatitis (rare)
Puncture of other organs – lung, kidney
Delayed complications of Percutaneous transhepatic biliary drainage
Biliary sepsis (cholangitis) – bacteria attach to foreign body
Catheter migration – dislodges when patient moves around
Bile leak into peritoneal cavity
Metastatic seeding
Skin infection
Image guidance modality for percutaneous nephrostomy
US only
Outline simplified procedure of percutaneous nephrostomy
- Puncture the calyx through the skin
- Inject contrast material to opacify the collecting
system using fluoroscopy - Pass a guide wire through the needle into the ureter
- Pass the drainage catheter over the wire and place into the ureter/ renal pelvis
