Dorsal Root Entry Zone
What You Need to Know
- The dorsal root entry zone (DREZ) lesioning procedure is a treatment for severe pain caused by nerves that have been torn away (avulsed) from the spinal cord or, less commonly, by spinal cord injury.
- DREZ lesioning may be appropriate when nonoperative pain therapies have not provided relief.
- The procedure itself involves a neurosurgeon entering the spinal cord and silencing the damaged areas of pain-signaling nerve cells.
Between 10 and 30 percent of people with spinal cord trauma and brachial plexus injuries suffer from unrelenting chronic nerve pain, which can be severe and debilitating both physically and mentally. In properly selected patients, dorsal root entry zone (DREZ) lesioning can restore a patient’s quality of life.
Nerve Pain Treated with DREZ Lesioning Procedure
Peripheral nerves connect the spinal cord to the rest of the body travelling as electrical cabling throughout the body. Damage to a peripheral nerve can lead to neuroma formation. Rarely, these neuromas can cause severe pain. This is treated with surgical resection of the neuroma if non-operative management fails.
Peripheral nerves can be torn away (avulsed) from the spinal cord, which damages the dorsal root entry zone of the cord, resulting in cells firing in a disorganized and uncontrolled way, similar to the electrical impulses within the brain that cause a seizure.
Unfortunately, these messages transmitted to the brain are interpreted as pain. Avulsion injuries are most commonly seen in severe brachial plexus trauma .
Collaborating to Control, Prevent and Eliminate Pain
Although pain serves a purpose to let us know when we have been injured, in many patients, the pain signaling system is somehow broken, resulting in chronic pain. The Neurosurgery Pain Research Institute at Johns Hopkins was developed using a generous gift from an anonymous donor to fundamentally transform our understanding of pain and to develop new and effective strategies to treat it.
DREZ Lesioning Procedure
First, the individual is assessed with MRI or CT scans/myelogram to look for avulsion injury of the spinal nerve roots that may be causing the pain.
During the actual procedure, the neurosurgeon gains access to the spinal cord by creating an opening in the spine called a laminectomy. The surgeon opens the dura, the membrane covering the cord.
Using a surgical microscope, the surgeon carefully isolates the area of the spinal cord damaged by the avulsed nerve roots. Using radiofrequency, laser, ultrasound or microsurgery, the neurosurgeon creates 60 to 120 precise lesions within the dorsal root entry zone.
In a successful DREZ lesioning procedure, the individual is likely to experience a significant reduction in pain, which should continue over the long term.