Pulsed RF treatment relieves back pain

The majority of patients with low back pain were pain free after receiving a new image-guided pulsed radiofrequency (RF) treatment, according to a study led by Alessandro Napoli from Sapienza University of Rome. The study included 80 patients with at least three months of low back pain due to a herniated disk that had not responded to conservative treatments. Patients underwent a minimally invasive procedure that used CT to guide a needle to the location of the bulging disc and nerve root. The researchers then inserted a probe through the needle tip and delivered pulsed RF energy to the area for 10 minutes.

Even without touching the disc, the pulsation served to resolve the herniation, with 81% of patients pain free one year after a single 10-minute treatment. Six patients required a second pulsed RF session, while 90% were able to avoid surgical treatment. No patients experienced side effects. "The probe delivers a gentle electrical energy, so there's no thermal damage," explained Napoli. "The results have been extraordinary. Patients have been relieved of pain and resumed their normal activities within a day. There's a big gap between conservative treatments for disc compression and herniation and surgical repair, which can lead to infection, bleeding and a long recovery period. Evolving technologies like this image-guided treatment may help a substantial number of patients avoid surgery."

No evidence that gadolinium harms the brain

A study headed up at the Mayo Clinic has found no evidence that gadolinium accumulation in the brain speeds cognitive decline. Gadolinium-based MRI contrast agents are used in 40–50% of MRI scans today, and while scientists previously believed the contrast could not cross the blood-brain barrier, recent studies found traces of gadolinium in the brain for years after MRI. However, little is known about the health effects, if any, of gadolinium retained in the brain. For this study, the researchers investigated the effects of gadolinium exposure on neurologic and neurocognitive function using the Mayo Clinic Study of Aging (MCSA), in which participants underwent neurologic evaluation and neuropsychological testing. The researchers compared the neurologic and neurocognitive scores of MCSA patients with and without previous exposure to gadolinium contrast.

The study included 4261 cognitively normal men and women, between the ages of 50 and 90, 25.6% of whom had received one or more doses of gadolinium contrast. After adjusting for age, sex, education level, baseline neurocognitive performance and other factors, the researchers found that gadolinium exposure was not a significant predictor of cognitive decline, dementia, diminished neuropsychological performance or diminished motor performance. "Right now there is concern over the safety of gadolinium-based contrast agents, particularly relating to gadolinium retention in the brain and other tissues," explained lead author Robert McDonald. "This study provides useful data that, at the reasonable doses 95% of the population is likely to receive in their lifetime, there is no evidence at this point that gadolinium retention in the brain is associated with adverse clinical outcomes."

Neurofeedback shows promise in treating tinnitus

Tinnitus, the perception of noise such as ringing in the ear, affects approximately one in five people. The primary auditory cortex, the brain region that processes auditory input, has been implicated in tinnitus-related distress. Now, researchers have shown that neurofeedback training could reduce the severity of tinnitus or even eliminate it. Neurofeedback training involves an individual training their brain by viewing an external indicator of brain activity – functional MRI (fMRI) in this study – and attempting to exert control over it. "The idea is that in people with tinnitus there is an over-attention drawn to the auditory cortex, making it more active than in a healthy person," explained Matthew Sherwood from Wright State University. "Our hope is that tinnitus sufferers could use neurofeedback to divert attention away from their tinnitus and possibly make it go away."

In the study, 18 volunteers with normal hearing underwent fMRI-neurofeedback training. The participants received white noise through earplugs and viewed the activity in their primary auditory cortex as a bar on a screen. The researchers used single-shot echoplanar imaging to provide an indirect measure of brain activity. Training sessions comprised 30-s "relax" periods, during which the volunteers watched the bar, alternated with 30 s "lower" periods, during which they actively attempted to lower the bar. By diverting their attention away from sound, the participants' auditory cortex activity decreased, as did the measured signal. A control group of nine individuals received sham neurofeedback – performing the same tasks but with feedback from a random participant, enabling the researchers to distinguish the effects of real neurofeedback on auditory cortex control. "Ultimately, we'd like to take what we learned from MRI and develop a neurofeedback program that doesn't require MRI to use, such as an app or home-based therapy that could apply to tinnitus and other conditions," said Sherwood.

3D-printed implants could help treat hearing loss

Conductive hearing loss occurs when the ossicles – three tiny bones in the middle ear - are damaged, due to trauma or infection, for example. While ossicular defects can be repaired using prosthetic implants created from stainless steel struts and ceramic cups, the surgery often fails. "One reason the surgery has a high failure rate is thought to be due to incorrect sizing of the prostheses," explained study author Jeffrey Hirsch from the University of Maryland School of Medicine. "If you could custom-design a prosthesis with a more exact fit, then the procedure should have a higher rate of success." With this aim, Hirsch and colleagues investigated the use of 3D printing to create customized prosthetic replacements for damaged parts of the middle ear.

The researchers removed the middle linking bone in the ossicular chain from three human cadavers, imaged the structures with CT and then 3D printed prostheses for each cadaveric bone. Four surgeons then performed insertion of each prosthesis into each middle ear, and were asked to match each prosthesis to its correct source. All four were able to correctly match the prosthesis to its intended temporal bone. The results suggest that CT scanners can detect significant anatomic differences in normal human ossicles, that these differences can be accurately 3D printed and, significantly, that surgeons can detect such differences. The next step will be to create prostheses out of biocompatible materials. The researchers are also looking at an approach that combines a lattice-like 3D-printed prostheses with stem cells that will grow on the lattice. "The stem cells would mature into bone and become a permanent fix for patients with hearing loss," Hirsch said.