Transcranial magnetic stimulation - a non-invasive technique that excites neurons in the brain by magnetic pulses introduced through the scalp - may be a useful treatment for tinnitus, according to results of a preliminary study.
Tinnitus is a persistent, inescapable sensation of ringing in the ears that affects millions of people, and in some it can lead to psychiatric distress, sleep disturbances, and work impairment.
Hard to treat
"Treatment of chronic tinnitus is difficult," Dr Eman M. Khedr of Assiut University Hospital, Egypt, and colleagues explain in the Journal of Neurology, Neurosurgery and Psychiatry. Drug therapy, cognitive therapies or electronic devices that attempt to cancel the tinnitus have all been tried either separately or in combination, but the success rate is not high.
"Recently, a number of promising reports have appeared, suggesting that repetitive transcranial magnetic stimulation (rTMS) might be a possible treatment," the researchers note.
To investigate, they randomised 66 adults with chronic tinnitus to receive rTMS or a sham treatment, applied daily for 2 weeks and then once per month for the next 4 consecutive months. The coil generating the magnetic field was positioned close to the skull over the left temporal region.
A good response
Compared with the sham treatment, the investigators observed a response in patients who received active rTMS. A good response (greater than 80 percent) was seen in six patients treated with rTMS at a frequency of 25 Hertz, five patients treated with 10 Hertz, and one patient who received 1 Hertz.
Partial responses (21 percent to 80 percent) were seen in six patients in the 25 Hertz group, eight in the 10 Hertz group and 12 in the 1 Hertz group. The remaining patients, about 24 percent, did not respond to active treatment.
Patients who had tinnitus for the longest period of time were the least likely to respond to rTMS treatment.
Khedr and colleagues conclude that "10 daily sessions of rTMS may be a safe and effective method of reducing symptoms of chronic tinnitus for several months."
SOURCE: Journal of Neurology, Neurosurgery and Psychiatry, February 2008. – (Reuters Health)