University of Maryland researchers are piloting a trial to treat neuropathic pain, or pain caused by nerve damage or a malfunctioning nervous system.
Recently they used an MRI-guided focused ultrasound to treat a Missouri woman whose hip pain was so severe she couldn’t get out of bed. Doctors couldn’t figure out what was causing the discomfort, and nothing seemed to relieve it. Finally, an evaluation of her brain activity showed that brainwaves were misfiring, sending phantom pain signals to parts of her body.
An estimated 100 million Americans suffer from neuropathic pain. Injury, infection, metabolic disease or a traumatic event can cause it, and patients describe it in a variety of ways — as burning, tingling, pins and needles or even stabbing pain. It’s often chronic and debilitating.
Enter Dr. Dheeraj Gandhi, professor of diagnostic radiology and nuclear medicine at the University of Maryland School of Medicine and director of neurointerventional radiology at the University of Maryland Medical Center. Gandhi had been researching ways to combat pain without radiation or invasive surgery. In this new approach, he and other physicians use acoustic energy to ablate cells within the body.
“If we can interrupt or carefully destroy the nucleus in the brain responsible for processing and amplifying pain signals, then we can disrupt this network and stop the neuropathic pain,” he says.
Doctors often prescribe medication, sometimes narcotics, anti-depressants or anti-epileptic medications, which work for many patients but can have a lot of side effects. In contrast, the MRI approach allows doctors to define the target inside the brain and create a zone of thermal heating that is well controlled and very precise, Gandhi says.
“We are going to target small, very tiny areas in the brain within the relay center of the brain called the thalamus,” he says. “When the patients get inside the magnetic resonance imaging, then we very slowly raise the temperature in the desired location or the target. We can examine the patient frequently since the patients are awake and can give us feedback. If the patient is showing improvement during early stages of the treatment, we try to go up on the heat and then we ablate this tiny target or nucleus that conducts these pain sensations.”
Currently, the study is limited to treat patients with sciatica pain, spinal cord injury and phantom limb pain. If it is a success, then the next step is to hold a more extensive trial and expand to other types of neuropathic pain that are widespread, such as diabetic neuropathy pain.
“My initial trial is approved to enroll up to 10 patients, and assuming we show the safety of this trial, then we will probably be designing a bigger, multi-center study,” Gandhi says.