Dorsal root entry zone localization using direct spinal cord stimulation: an experimental study

Area of Science:

• Neuroscience
• Spinal Cord Research
• Electrophysiology

Background:

• Accurate identification of the dorsal root entry zone (DREZ) is crucial for spinal cord surgery.
• Existing methods for DREZ identification may lack precision.
• Electrophysiological mapping offers a potential alternative for precise localization.

Purpose of the Study:

• To evaluate the efficacy of direct spinal cord stimulation and recording for identifying the DREZ and long tracts.
• To compare electrophysiological responses following stimulation of the dorsal versus dorsolateral spinal cord.
• To establish electrophysiological criteria for DREZ identification.

Main Methods:

• Direct spinal cord stimulation and intrathecal recording were performed in five dogs.
• Electrophysiological mapping techniques were employed to target the dorsal and dorsolateral spinal cord.
• Stimulation intensity and evoked responses were systematically analyzed.

Main Results:

• Conduction velocity was higher with low-intensity dorsolateral spinal cord stimulation compared to dorsal stimulation.
• Evoked responses were larger following dorsolateral stimulation than dorsal stimulation at specific intensities.
• Electrophysiological mapping successfully identified the DREZ based on distinct criteria.

Conclusions:

• Direct spinal cord stimulation and recording is a valuable technique for identifying the DREZ.
• Dorsolateral spinal cord stimulation provides more robust electrophysiological signals for mapping.
• This electrophysiological approach enables DREZ identification using objective criteria alone.