The University of Maryland physician-scientists has treated the first patient in the United States with MRI-guided focused ultrasound for neuropathic leg pain as part of a pilot clinical trial.

"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," says lead researcher Dheeraj Gandhi, MBBS, professor of diagnostic radiology and nuclear medicine at the University of Maryland School of Medicine (UMSOM) and director of neuro-interventional radiology at the University of Maryland Medical Center (UMMC).

An estimated 100 million Americans suffer from neuropathic pain, a type of chronic pain caused by nerve damage or a malfunctioning nervous system that carries pain signals to the brain. 

Neuropathic pain

The pain is not precipitated by a physical event such as accidentally hitting your thumb with a hammer. It can be a result of some things, including injury, infection, metabolic disease or a traumatic event. People often describe the neuropathic pain as burning, tingling, pins, and needles, and shooting or stabbing pain.

Chronic neuropathic pain is difficult for doctors to treat because it does not respond well to common pain medications. Current treatments include medications, nerve blocks, implantable devices, and physical therapy.

Approximately $ 530 billion is spent annuallyincaring for people with neuropathic pain. It can cause marked disability in some people, with many unable to work or be productive. 

Patients not only havepain, but they can become depressed, have trouble thinking clearly or falling sleep. The medications are often significant, and there are significant risks for drug toxicity and addiction. There is an unmet need for safe and more effective pain therapies.

Tammy Durfee of Kansas City, Missouri, woke up one morning with a pain in her hip that was so severe she could not get out of bed. Doctors could not figure out what was causing the pain, and nothing seemed to highlight it. 

"I could not sit still, I was always fidgeting and moving around to try and get comfortable, but I never could," said the 56-year-old pharmacy supervisor. 

Over the next eight years, she would try electronic nerve stimulators, cortisone shots, narcoticsandother medications. Some treatments did not work at all; others would work for a little while, and then stop.

An evaluation of her brain activity showed that brainwaves were misfiring, sending phantom pain signals to parts of her body. Her neurosurgeon diagnosed cerebral dysrhythmia as the cause of her neuropathic pain and recommended a radiation procedure. But after learning her insurance would not cover it, Durfee started researching alternative treatment options.