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Updated: Aug 2, 2026
06:39
Live Imaging of Dorsal Root Axons after Rhizotomy
Published on: September 1, 2011
Pain control with laser-produced dorsal root entry zone lesions.
S K Powers1, N M Barbaro, R M Levy
1Division of Neurological Surgery, University of North Carolina, Chapel Hill.
Applied Neurophysiology
|January 1, 1988
Summary
Laser dorsal root entry zone (DREZ) lesions provided significant pain relief for patients with brachial plexus avulsion and some paraplegics. This microsurgical technique shows promise for specific deafferentation pain types, potentially via tract of Lissauer impulse interruption.
Area of Science:
- Neurosurgery
- Pain Management
- Neurology
Background:
- Deafferentation pain is a challenging condition often poorly managed by conventional treatments.
- Microsurgical techniques offer potential therapeutic avenues for refractory neuropathic pain.
Purpose of the Study:
- To evaluate the efficacy of laser-produced dorsal root entry zone (DREZ) lesions for pain relief in patients with deafferentation pain.
- To identify patient subgroups that benefit from this specific microsurgical intervention.
Main Methods:
- Microsurgical laser DREZ lesions were performed on 40 patients presenting with diverse deafferentation pain etiologies.
- Patient outcomes regarding pain relief were assessed over the long term.
Main Results:
- Significant long-term pain relief was observed in patients with brachial plexus avulsion and in a subset of paraplegic patients.
- Patients with pain secondary to arachnoiditis or peripheral nerve injury/neuropathy did not experience pain relief.
- Laser DREZ lesioning demonstrated efficacy in several other small patient subgroups.
Conclusions:
- Laser DREZ lesions are a viable treatment option for specific types of deafferentation pain, notably brachial plexus avulsion and certain cases of paraplegia.
- The mechanism of pain control may involve the interruption of impulses within the tract of Lissauer, facilitated by the precise lesion dimensions achievable with lasers.
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