RAD 354 Chapt 22 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