Radiologists have applied a pioneering technique to reduce phantom limb pain – a type of chronic pain experienced by patients with amputated limbs. The physicians have applied a minimally-invasive technique known as cryoablation therapy, which uses extreme cold to effectively silence the nerve cells at the site of the amputation.
“Until now, individuals with phantom limb pain have had few medical interventions available to them that resulted in significant reduction in their pain,” said Dr. J. David Prologo, assistant professor in the division of interventional radiology at Emory University School of Medicine. “Now, these individuals have a viable treatment option to target this lingering side effect of amputation—a condition that was previously largely untreatable.”
According to the Centers for Disease Control and Prevention, nearly 200,000 amputations are performed in the US each year. People living with amputated limbs include patients with advanced, uncontrolled diabetes, and military veterans who were wounded in combat.
Prologo and his team at Emory University, treated 20 patients with image-guided cryoablation of both nerves and scar tissue present in what’s left of their limb. This technique uses a hollow probe which is inserted through the skin and into the residual limb.
Once localized to the correct spot, the temperature of the probe is decreased dramatically by a circulating coolant. This cooling establishes an ablation zone within the residual limb, thereby disrupting nerve signals.
In order to test the effectiveness of the cryoablation therapy, the researchers asked the patients to rate their pain level on a visual analog scale (VAS) from 1 (not painful) to 10 (extremely painful). They took three measurements – before, seven days after and 45 days after the procedure.
On average, the patients rated their pain level as 6.4 before receiving cryoablation therapy. At 45 days post-procedure, the average pain score had decreased to 2.4 points.
“Many of the nerves contributing to these pains are inaccessible to physicians without image guidance,” said Prologo. “With the interventional radiologist skill set, we can solve tough problems through advanced image-guided therapies, and this promising treatment can target hard-to-find nerves and help amputees dramatically improve their lives—all in an outpatient setting.”