A one-time treatment that zaps the brain with powerful ultrasound waves can ease disabling tremors that affect more than a million Britons.
The procedure can give patients their lives back, experts say, restore mobility and help them cope with simple activities such as drinking a cup of tea. However, only a handful of people with the nervous system problem, known as essential tremor, have been offered the treatment as it is only available at two hospitals in England.
Essential tremor is a neurological disorder that causes involuntary shaking of parts of the body, especially hands, legs and jaws. It is the most common state of tremor in the UK, affecting five times as many people as Parkinson’s, which also causes tremors and most often occurs after the Middle Ages.
A one-time treatment that zaps the brain with powerful ultrasound waves can ease disabling tremors that affect more than a million Britons
Although experts do not know the exact cause of essential tremor, it is thought to be triggered by abnormal electrical signals in the brain that transmit tremors through the nervous system to the muscles.
Although experts do not know the exact cause of essential tremor, it is thought to be triggered by abnormal electrical signals in the brain, which transmit tremors through the nervous system to the muscles.
Professor Wladyslaw Gedroyc, consulting radiologist at the Imperial College Healthcare NHS Trust, which offers ultrasound treatment, says: ‘Significant tremor can cause extreme difficulties. People with it say that they feel embarrassed that they are shaking uncontrollably, so also avoid going out.
Mild cases are often left untreated, but some patients are offered propranolol, a blood pressure medication that also suppresses tremors.
But as patients worsen, more powerful drugs are needed. These include primidone, an anti-seizure drug that reduces tremors but can trigger side effects such as extreme drowsiness. About a quarter of patients do not respond to any medication.
Until now, the only option for these patients has been deep brain stimulation. This invasive treatment, which costs around £ 50,000 per patient, involves implanting a tiny electrode in a part of the brain called the thalamus, which helps control the body’s movements. This is connected by wires under the skin to a small electric generator implanted in the chest. The current supplied to the thalamus disrupts the nerve signals that cause tremors.
Studies show that deep brain stimulation is effective in up to 90 percent of cases. However, over time, scar tissue builds up around the electrode, reducing its efficiency.
The new treatment, known as MRI-guided focused ultrasound, is performed under local anesthesia and costs around £ 26,000 – half the price of deep brain stimulation. Patients lie inside an MRI scanner to locate the thalamus, which then receives rays of ultrasound fired at it – energy waves like those used for pregnancy scans, but 40,000 times more powerful. The rays generate heat, making the area responsible for the vibrations.
This gives ‘a significant, immediate reaction with few side effects’, says Prof. Gedroyc. “We can improve the severity of tremors by 80 to 90 percent.”
Currently, the biggest challenge for patients is accessing treatment. MRI-guided focused ultrasound is currently only offered by the Imperial College Healthcare NHS Trust in London and The Walton Center NHS Foundation Trust in Liverpool. As a result, only 69 patients have received treatment to date, and 184 are on the waiting list.
One patient to benefit from is Keith Pearson, 73, a musician from Cambridge. The married father of two had suffered from significant tremor in his right hand for 30 years. It steadily got worse until he could no longer play his banjo. He says: ‘My hand had its own mind. Then I noticed that I had a hard time writing. ‘
Mr. Pearson underwent treatment in November. He says: ‘They jumped me out of the MRI scanner once in a while and asked me to draw a spiral. Extraordinarily, on the fifth time I asked, the spiral came out perfectly – I was just as surprised as everyone else. Then I took a cup of tea with one hand and did not waste it – the first time I had managed it in 15 years. ‘
The tremors have been suppressed so successfully that Mr Pearson is now able to play the banjo again – something he feared would never happen.
