spine

Question 1

6. All of the following techniques may be used to aid in identifying the level of interest in a thoracic diskectomy procedure EXCEPT:
   A. Intraoperative lateral fluoroscopy with counting levels starting from the
   sacrum and moving rostral with midline needle localizers
   B. Intraoperative anteroposterior (AP) fl uoroscopy with counting levels starting
   from the 12th rib and moving rostral with midline needle localizers
   C. Intraoperative AP fluoroscopy with counting levels starting from the fi rst rib
   and moving caudal with midline needle localizers
   D. Neuronavigation with skin surface fiducial registration
   E. Neuronavigation with spinal bony landmark registration within the proximity of the level of interest

Answer 1

6.D. Although skin surface fi ducial registration is commonly used in brain neuronavigation, it is not very eff ective in the spine due to the parallax that is seen from
registering on the skin and attempting to navigate at the level of the bone, which
tends to be signifi cantly deeper than the level of the skin. The other techniques
described for localization are eff ective in identifying the level of interest in that
the thoracic spine adequately.