Interventional Radiology

Question 1

INTRO

i) what is it?
ii) name three common interventional procedures

Answer 1

i) image guided diagnostic/therapeutic procedurees through percutaneous puncture of a vessel/organ via body opening
ii) iliac/femorall angioplasty and stenting, renal artery stenting, nephrostomy, fibroid embolisation, visc embolisation for trauma/haemmorhage, oncology

Question 2

PATIENT PREP

i) what must INR be less than? why?
ii) what must platelet count be? name a patient group this may not apply to?
iii) name two drugs that can be given to sedate
iv) what are most preventable deaths from trauma caused by?

Answer 2

i) INR <1.5 - make sure they dont have a coagulopathy
ii) Plts >50-80 apart from lymphoma/leukaemia patients
iii) midazolam and fentanyl
iv) most preventable deaths caused by untreated haemmorhage

Question 3

MAJOR ARTERY DISRUPTION

i) what type of injury/accident can lead to aortic transection (rupture)? which structure is damaged?
ii) what causes a widened mediastinum?
iii) how is aortic transection managed?

Answer 3

i) decelleration injury > chest organs are pushed forward
- ligamentum arteriosum can be torn from aorta > haemmorhage

ii) wide mediastinum due to build up of blood/fluid
iii) manage by deploying a graft/stent into damaged area

Question 4

EMBOLISATION

i) name three indications for embolisation
ii) what is the most common permanent embolic agent?
iii) name a temporary embolic agent

Answer 4

i) traumatic bleeding, post part haemmorhage, GI bleeding
ii) coils (silk is thrombogenic)
iii) gelatin sponge

Question 5

SOLID ORGAN INJURIES

i) which imaging technique can be used to grade the injury?
ii) what type of management may haemodynamically stable patients need?
iii) give three indications where embolisation for haemorhage is preferred to surgical intervention

Answer 5

i) CT
ii) conservative mx - observe but keep in hospital
iii) embolisation vs sx - rapid occulsion/difficult surgical access, patient has a high anaesthetic risk eg elderly, when embolisaation can limit amount of tissue lost

Question 6

RENAL TRAUMA

i) which two grades of renal injury can be managed by IR?
ii) which grade will probably need a nephrectomy?
iii) what procedure can be done to prevent bleeding?

Answer 6

i) Grade II and III
ii) grade V
iii) renal embolisation

Question 7

INTERVENTIONAL ONCOLOGY - TACE

i) what is TACE?
ii) name two tumours it may be useful in?
iii) which drug can be admin? how is it delivered?
iv) name another substancee that can be given alongside RT?
v) why can lipiodol be used too increase local doses?
vi) what additional effect can this treatment have

Answer 7

i) trans arterial chemo embolisation (deliver chemo straight to tumour blood supply)
ii) hepatocellular carcinoma and colorectal mets
iii) Dox delivered in beads
iv) Iodine
v) lipiodol is selectively uptaken by hepatocytes therefore can be used to target the tumour
vi) can deliver local chemo but also cut off blood supply to tumour (ischaemic effect)

Question 8

PERCUTANEOUS ABLATION -RFA

i) how does radiofrequency ablation work?
ii) name three tumourrs RFA can be used in?
iii) what size of tumour can be it used for?
iv) how does cryoablation work?

Answer 8

i) put needle into tumour and extend prongs > deliver high dose radiofreq to ‘cook’ tumour and some normal tissue
ii) lung, liver, RCC
iii) optimum size is 2cm but can be used up to 3cm
iv) freeze tumour cells by running liquid nitrogen through the needle > apoptosis