Special Equipment

• Anesthesia
  
• Somatosensory evoked potential/motor evoked potential monitoring
  
• Electroencephalogram monitoring
  
• Nuclear tracer
  
  
  
  • 99m Tc-ethyl cysteinate dimethylester
    
  • 99m Tc-hexamethylpropyleneamine oxime
  
  
• Nuclear (gamma) scanner (postprocedure)

Adjunct Monitoring

• Transcranial Doppler
  
• Computed tomography with xenon
  
• Magnetic resonance imaging with diffusion-weighted imaging/fluid-attenuated inversion recovery
  
• Magnetic resonance angiography/computer modeling
  
  
  
  • Magnetic resonance angiography
    
  • Baseline single photon emission computed tomography (SPECT)
    
  • Angiography

Operating Room Set-up

• As for standard angiography
  
• Somatosensory evoked potential/motor evoked potential monitoring in room
  
• Anesthesia machine in room

• Awake (neuroleptanalgesia)
  
  
  
  • Fentanyl or hydromorphone drops
    
  • Midazolam drops
  
  
• No paralysis if neuromonitoring
  
• Foley catheter
  
• Radial or femoral arterial line
  
• Blood pressure cuff pressures
  
• Heparin injection (5000 U) plus additional boluses to maintain drops at two to three times baseline and activated clotting time > 300 second (1000 to 3000 units per hour)
  
• Brain protection
  
  
  
  • Hydration therapy (normal saline at 150 mL/hr for 4 hours)
    
  • Dexamethasone (4 mg intravenously every 6 hours)
    
  • Nimodipine (60 mg every 4 hours)
  
  
• Antiplatelet agents (acetylsalicylic acid and clopidogrel) for 4 days

Positioning

• Supine position, head slightly elevated

Access

• Femoral arterial access
  
• Seldinger technique
  
• Unilateral versus bilateral
  
• Seven to 8 French (F) access

Initial (Diagnostic) Angiography

• Standard diagnostic 3- or 4-vessel cerebral angiogram
  
• Assess circle of Willis and communicators
  
• External carotid views: assess collaterals plus possible extracranial/intracranial bypass planning
  
• Baseline SPECT

Cervical Carotid Artery Occlusion

• Five to 6F balloon (i.e., Swan-Ganz catheter) positioned in proximal internal carotid artery (ICA)
  
• Assess ICA occlusion with angiography

Monitoring During the Occlusion Trial

Permanent Occlusion

• Selverstone clamps
  
• Detachable silicone balloons
  
• Platinum coils
  
• Distally as possible for ICA
  
• Extradural proximal (skull base) branches of ICA in petrous, lacerum, cavernous segments of ICA
  
  
  
  • Vidian artery: second most common
    
  • Caroticotympanic artery
    
  • Meningohypophyseal artery: most common
    
  • Inferolateral trunk
    
  • Persistent trigeminal artery

• SPECT imaging to assess perfusion of nuclear tracer
  
• Close neurologic and hemodynamic monitoring (fluid status, blood pressure)
  
• Additional imaging (magnetic resonance imaging with diffusion-weighted imaging/fluid-attenuated inversion recovery)
  
• Heparin for 48 hours in occlusions