Vascular and Interventional Radiology
Access and technique
Most procedures begin with the Seldinger technique: needle puncture, guidewire placement, then catheter exchange under fluoroscopic or ultrasound guidance. Distinguish diagnostic angiography from embolisation, and know coaxial catheter systems and microcatheters.
Embolisation agents
Coils for focal arterial haemorrhage, pseudoaneurysms and arteriovenous fistulae; particles for tumour devascularisation and diffuse bleeding; liquid agents (glue, ethylene vinyl alcohol copolymer, sclerosants) for arteriovenous malformations and varices; balloons for temporary proximal control. Post-embolisation syndrome (pain, fever, nausea) is expected after tumour embolisation and is not infection.
Oncology
TACE combines chemotherapy with embolisation; TARE delivers yttrium-90 microspheres and is not embolic in the same sense. Know indications and contraindications, and follow up with enhancement criteria.
Aortic and peripheral disease
EVAR requires an adequate proximal neck, suitable access vessels and landing zones. Endoleak types: I attachment site, II branch vessel, III graft defect, IV graft porosity, V endotension. Type II is often observed, while types I and III require treatment. Peripheral arterial disease is graded by TASC lesion classification.
Traps
Non-target embolisation causes ischaemia. Consider contrast nephropathy and procedural radiation dose to patient and operator. Do not confuse TACE with TARE, or arterial with venous access.
Rule of thumb
After EVAR: type I or III endoleak - treat; type II - usually observe unless the sac continues to expand.