RAD 354 Chapt 27 Interventional Radiology

• Diagnostic Imaging

• Therapeutic (interventional)

Brief History

• 1930’s angiography• 1953 – Seldinger needle/technique• 1960’s transbrachial selective coronary

angiography (common femoral artery is the MOST commonly accessed artery for access to other internal organs/structures)

Seldinger Needle

Seldinger Technique

• The blunt tipped outer cannula is filled with the SHARP inner (cutting) stylet and cuts through the artery. The cutting stylet is removed and the blunt outer cannula is fitting into the artery. The guide/glide wire can be inserted trough the outer obturator and into the artery and threaded toward the area of interest. When it reaches the desired area, the catherter is placed OVER the guidewire and pushed to the right location.

Seldinger technique con’t

• Once the catheter reaches the correct location, the guidewire is removed and contrast can be introduced through the catheter to the proper site

Imaging Procedures

• Angiography• Aortography• Ateriography• Cardiac Catherization• Myelography• Venography

Interventional Procedures

• Stent placement• Emobization• Intravascular stent• Thrombolysis• Balloon angioplasty (PTA)• Artherectomy• Electrophysiology

Materials Needed

• Informed consent• Needle (usually Seldinger 18 g)• Guide/glide wires• Catheters (H1- “headhunter,” C2 – “Cobra,”

Pigtail)• Heparin saline for “flushing”• Contrast – most is now nonionic – fewer side

effects

Pt. Prep and Monitoring

• Prep – NPO 8 hours prior and usually hydrating IV’s

• During procedure – cardiac monitoring, blood pressure and pulse ox

• Post – MANUAL pressure on the puncture site (usually 20 minutes), followed by a sandbag for several hours after to prevent bleeding

• Lots of water!!!

Equipment Considerations

• Tube– Focal spot size 1.0mm/0.1mm– Disc size 15cm diameter (heat load)– Power rating – 80kW (rapid sequence, serial

radiography)– Expanded anode hear capacity (massive amounts

of heat are produced)Couch – non-tilting, slim design with “stepping” capability

Filming Considerations

• Cine camera for cardiac catherization (cam and fluoro are synchronized so the fluoro only emits x-ray when the film frame is accessible)

• Photofluorographic camera• Charge-Coupled Device (CCD) – photosensitive

silicon chips (replacing the TV camera) convert light to digital video images

Balloon Tip for PTA

Balloon Imaging

Pig tail

Stent

Wireless Technology