Operative Planning

• Review imaging (magnetic resonance imaging)

Routine Equipment

• Laminectomy instruments
  
• Microsurgical instruments
  
• High-speed drill (optional)

Special Equipment

• Consider neurophysiological monitoring of somatosensory evoked potentials and motor evoked potentials

Operating Room Set-up

• Open-frame spinal table or electric table with bolsters or Wilson frame
  
• Ensure ability to obtain anteroposterior and lateral radiographs to confirm operative levels
  
• Headlight
  
• Loupes (optional)
  
• Bipolar and Bovie cautery
  
• Microscope with bridge

Anesthetic Issues

• General anesthesia
  
• Arterial line for blood pressure monitoring
  
• Intravenous antibiotics (cefazolin 2 g or vancomycin 1 g for adults) should be given 30 minutes prior to incision
  
• Dexamethasone is given to reduce swelling
  
• Minimize halogenated inhalational agents and nitrous oxide if neurophysiological monitoring performed

Positioning

• Patient prone
  
• Secure head with foam mask, Gardner-Wells tongs with 15 lb of traction, or Mayfield head holder
  
• If using foam mask, ensure no ocular pressure
  
• For lesions at T6 or above, pad arms and tuck along sides; for more distal lesions, abduct shoulders and flex elbows 90 degrees

Sterile Scrub and Prep

• As for posterior cervical or posterior thoracic approach

Incision

• Center linear midline incision over the levels of the lesion to permit exposure of one level above and one level below the lesion

Laminectomy

• Bilateral subperiosteal exposure to medial facet joints bilaterally
  
• Perform bilateral laminectomies from one level proximal to one level distal to the cavernous malformation
  
• Do not violate facet joints (may lead to postoperative kyphotic deformity)
  
• Wax bone edges, obtain meticulous epidural

Dural Opening

• Open dura in midline
  
• Secure edges of dura to paraspinal muscles with 4–0 silk tacking sutures