15th July 2014
A gel injected into the ear could be a radical new treatment for tinnitus, the buzzing or ringing in the ears that affects five million people in the UK.
The gel contains a new drug that appears to halt damage to nerve cells in the ears which leads to some ling-term cases of tinnitus.
Early results from clinical trials suggest it can halve the volume level of tinnitus in about 40% of sufferers. But as it is likely to work only in the early stages of the condition – while there is still a chance to repair some f the damage to the inner ear – the gel is being tested only on patients who have had tinnitus for under a year.
Many of us suffer temporary tinnitus that lasts no more that a few hours, often from a cold or after going to a loud concert. But for around one in 100 people, it becomes a long-term affliction.
When the ear are exposed to loud noise or infections, the tiny hair cells that transmit sounds to the brain become stressed and start to emit excess quantities of glutamate, a type of chemical messenger known as a neurotransmitter.
Called a ‘glutamate storm’, this over-stimulates nerve cells in the inner ear to the point where they eventually die. These nerve cells have the job of sending sound impulses up to the auditory cortex, the part of the brain that processes noise. When the nerve cells in the inner ear die, it leaves nerve cells in the auditory cortex in a permanently switched-on state, where they constantly relay sound to the brain, even when there is no incoming signal from the ear.
By this point, the tinnitus is no longer being caused by the damaged ear cells but is rooted in the brain itself. There are no drugs for tinnitus, and treatments include counselling and relaxation techniques to ease the stress that can make it worse. Another option is sound therapy, where the patients listen to the background noise, such as gentle music, to distract their attention from the tinnitus. But none of these actually get rid of the problem.
The new gel, which is being trialled at eight hospitals around the UK, as well as in centres in Europe and the U.S., contains a drug known as AM-101, which targets a receptor on nerve cells that allows glutamate to get in. By blocking this receptor, it can stop glutamate from binding to the nerve cell and causing damage. This then gives the damaged nerve cells a chance a regrow before tinnitus can set in for good.
The gel is injected through the ear drum three times over a period of five days. Half those who volunteer for the trial will get the active gel and half a placebo.
In a small study last year at Antwerp University Hospital in Belgium, published in the journal Otology and Neurology, 248 patients aged 16 – 65 years were given the real gel or a placebo. Forty-two per cent reported their tinnitus was half as quiet as before, compared with 14 per cent in the placebo group. After 90 days, 57% of those taking the active gel said their tinnitus was ‘much improved’ or ‘very much improved’.
John Phillips, consultant ear, nose and throat surgeon at Norfolk and Norwich University Hospital = one of the UK trial centres recruiting volunteers – said: ‘This is quite exciting because the preliminary data is encouraging. Some people got rid of their tinnitus completely, but it doesn’t appear to work for everybody. Also, It is only suitable for people who have had tinnitus for less than a year and where it can be attributed to a specific cause, such as a loud blast of noise or an ear infection.’
For UK trial details go to tinnitus-study.info/uk-study-centres.
All information contained in the above article belongs to: http://www.dailymail.co.uk/health/article-2692010/Gel-stops-constant-buzzing-ears.html
