Brain wave: The pioneering treatment changing Parkinson's treatment

The tremor was overwhelming. It persisted day in and day out. A constant shake that never let up, not even for a moment, no matter how hard he tried. 

He would sit on his hands, concentrating on the movement and willing it to go away, chasing the thought of the stillness that would wash over him if the shaking stopped.  

But that stillness never came. Peter Scott’s right arm would just not stop shaking. 

“The tremor is running our house,” says Margaret Scott, Peter’s wife. “It’s running him and it’s running me. Everything revolves around this tremor because it’s all we talk about it, whether it is bad day or whether it is a good one.” 

In 2021 Peter was diagnosed with Parkinson’s disease. It was a shock, but the signs had been there for over 20 years.  

It started in his fifties with a pain in his elbow that he dismissed as fatigue from work, then a shaking in his thumb which was an annoyance, but Peter was tough. Eventually that shake developed into a tremor that ran down his entire arm and into his hand. By the age of 72, he could barely use a knife and fork. 

“A lot of my memories from my childhood are of spending time with my dad,” says Peter’s son, Euan. “I would go along with him and help him at work as a joiner. My dad was always the person to fix stuff, whereas now, with the condition he’s in, he’s not able to fix anything.” 

Over 13,000 people in Scotland have been diagnosed with Parkinson’s, with most patients aged over 65. The disease is caused by a loss of nerve cells in part of the brain called the substantia nigra. This loss of nerve cells leads to a reduction in the chemical dopamine, which plays a vital role in regulating the movement of the body. Exactly what causes the loss of nerve cells is unclear, but most experts think that a combination of genetic and environmental factors could be responsible. 

“He was always very cheery and jolly, but that all changed,” says Margaret. “Now I see this man who used to be so big and strong take half an hour to put his clothes on with my help. I just stand waiting with something to help him on with or to help him dry after a shower. It’s taken away his dignity; he doesn’t like being like this at all.” 

The main symptoms of Parkinson’s disease present as tremors, slow movement and stiff and inflexible muscles. People with the disease can also experience additional symptoms that range from memory loss to depression and anxiety. 

“I think with that is where frustration can come from with people that suffer from Parkinson’s,” says Euan. “It’s that frustration of not being able to do the things that you could do. The really simple things, far less fixing a window or a leaking tap, it’s just the things that many of us take for normal he can’t do.”

Medication prescribed to ease Peter’s tremor didn’t work as well as expected. The pills caused unpleasant side effects – he suffers from coeliac disease and doctors couldn’t be sure that medications given to him were gluten-free. But then, one afternoon while watching TV, Peter spotted a surgery that gave him hope. 

Flashing across his screen was the story of Ian Keir, a 63-year-old from Carnoustie who had tremors from Parkinson’s in his right hand, the same as Peter, until he didn’t. 

“I just couldn’t believe it,” says Peter in a voice barely above a whisper. The constant tremor has even taken the strength out of his voice. “I just found it unbelievable that there was nothing out there that can help, and then I saw that, which wasn’t a cure but at least it could help.” 

Ian’s tremor stopped after he underwent a procedure in 2024 called ultrasound thalamotomy, a non-invasive form of brain surgery. The procedure was performed at Ninewells Hospital by neurologists Dr Tom Gilbertson and Dr Sadaquate Khan, part of the University of Dundee’s School of Medicine.  

Ultrasound thalamotomy is a non-invasive surgery that uses over 1,000 highly focused ultrasound waves to create a targeted lesion on the brain. It was pioneered in the 1940s and 50s, when surgeons used ultrasound to create lesions on the brain through a hole in the skull. By the early 2010s the surgery had progressed to using Magnetic Resonance Imaging (MRI) to guide surgeons, eliminating the need for an invasive approach. This means that patients can be kept awake and responsive throughout the surgery, with minimal side effects and recovery times afterwards. 

To perform the surgery, ultrasound waves are directed by a surgeon observing through an MRI machine to damage a specific spot in a part of the brain called the thalamus. The waves are harmless on their own, but when combined on a point no bigger than a millimetre they act like a magnifying glass, permanently damaging the brain’s tissue after only a second of exposure. 

The thalamus acts as the brain’s central relay station, processing information for vision, hearing, touch and movement while also sending signals to the cerebral cortex and managing consciousness, alertness, sleep, memory and attention.  

The treatment has been used to treat people suffering from Essential Tremor, a neurological condition that causes tremors similar to Parkinson’s, but its application for Parkinson’s patients is still being studied. 

“Peter’s one of a small number of people that we’re treating as part of a research study to see whether this approach works with Parkinson’s patients,” says Gilbertson. “I’d say for this study we reject nearly 90 per cent of the patients who get referred in, but for Peter, his tremor is disabling and severe enough to warrant the risks of surgery. Because of that we felt he was probably better suited to this surgery than other forms of more invasive neurosurgeries.”

Dressed in black thermal pyjamas and lying on a cold MRI table in a pristine room, Peter is attempting to draw a spiral. 

The pen shakes in his hand as he moves, scratching a line that starts out in the middle and slowly works towards an unsure conclusion. The resulting art isn’t pretty; the line wobbles erratically, weaving off-piste before violently returning to its track.  

It’s all part of a number of tests he will repeat throughout his thalamotomy, designed to track the effectiveness of the procedure in real time so that surgeons can make the tiny adjustments needed to ensure success.  

For Peter, the most crucial test involves a bottle.  

Ever since the tremor developed, Peter has been unable to drink a full glass of water without spilling the contents of the cup over himself. Now, as he attempts to bring the tip of the water bottle to his lips, Gilbertson watches intently. 

In his pre-operation assessment, Peter expressed a desire to be able to simply drink without spilling, post-surgery. This will be the main goal for Gilbertson and his colleagues, who hope to restore Peter’s ability to hold an object within touching distance of his lips without problem. 
“At the moment, I have to have what I call Parkinson cups,” says Peter with a smile. “Which is about half a cup of tea because if you have too much, you’ve got nothing left. I just want to be able to make myself and my wife a cup of tea and actually drink it.” 

The MRI machine whirrs slightly as Peter moves inside, his head locked into a cage that prevents even the slightest movement. Slowly the screens in the MRI control room light up, bathing the expectant faces staring through the protective glass in a cool glow. 

The path to this moment wasn’t straightforward. It took Peter and his family down a winding road that involved multiple consultations, medications and the explorations of private surgery options until a conversation with Dr Maria Corretge, Peter’s physician, pointed them in the direction of Dundee and an MRI room in the bowels of Ninewells Hospital. 

The light reflects off Khan’s glasses as he examines the scan of Peter’s brain laid out on the screen in front of him. To the uneducated eye the image looks like a jumbled mess of black and grey patches, but Khan knows exactly where he wants to go. Time spent studying previous scans has ensured he knows Peter’s brain almost as well as his own. 

“Every brain varies to some degree in terms of the anatomy,” says Gilbertson. “We start at very low energies of ultrasound to interrogate the brain tissue and see what the feedback is from both the patient and whether you’re starting to see improvement in tremor response. Then, towards the end of the procedure, what we’re trying to do is generate 100 per cent doses that are killing the cells and destroying the actual tissue.” 

To achieve a 100 per cent dose of ultrasound, Khan slowly builds up the amount of heat present in one spot, eventually reaching a critical point of 55 degrees. At this temperature, the surgeons hope that the heat is enough to permanently damage the part of the thalamus that controls Peter’s tremors, resulting in an immediate change to his quality of life and the lives of those around him. 

“Pre-Parkinson’s we were always very busy and very active,” says Margaret. “But now he is too tired. The best way to think about it is if you’ve left your car running and how, whether it’s electric or its fuel fired, it will eventually run out. That’s what happens for Peter but his engine never stops; even if it’s run out, it runs him out as well.” 

Peter and Margaret met as teenagers, marrying in 1979 and having their son Euan a few years later. The couple live in a farmhouse near the port town of Eyemouth in the Scottish Borders, where Margaret was born. Before his disease took hold, Peter renovated the farmhouse to create a place where the whole family, including Euan’s wife and two sons, could spend time together.

Now he can barely climb the same stairs he had a hand in building. 

“I always look at my father and think he’s got so much to give,” says Euan. “But the constant shaking really inhibits that ability. My dad wants something to change. He wants to be helping out, getting involved in the garden and out playing with his grandchildren and he just can’t do it.” 

Gathered around the MRI scanner, Gilbertson and Khan are discussing the merits of continuing Peter’s surgery. His tremor has been reduced after an hour of treatment, but not by as much as they had hoped. It’s still noticeable in his efforts to put the water bottle close to his lips, the tremor is still there.  

The decision is taken to shift the spot in the brain where the ultrasound waves are focused by around a millimetre to create two lesions instead of one. The surgeons hope this will create enough heat and damage to the brain’s structure to improve Peter’s condition.  

Ninewells Hospital is the only NHS hospital in Scotland that provides an ultrasound thalamotomy service as part of a 10-year research programme in collaboration with the University of Dundee. The machinery used in the surgery costs over £1m and was purchased with funds gathered through philanthropic donations. The lifespan of the machine is set to expire in five years’ time, with no plans in place to replace the service through NHS Scotland. In England, the NHS has funded the service since 2021. 

“What we need is a process which will allow us to invest in a long-term bit of infrastructure in Scotland from the NHS to deliver these treatments,” says Gilbertson. “We’re not expecting them to write out a blank cheque for a few million pounds to buy a new system, but just some contribution because this is an NHS service that we’re delivering through philanthropy so far.” 

Since the research project began, Gilbertson and his team have treated over 90 patients in Dundee, eliminating the need for patients to travel to England for the surgery, saving the NHS both money and time. 

“I think what we’ve demonstrated with the last five years is that there is a clinical need,” says Gilbertson. “We’ve treated nearly 100 people and we’re currently treating three patients a month. But if we don’t get behind this properly in terms of NHS Scotland’s buy-in, then this will fall off a cliff in five years’ time and you’re not going to see this in Scotland.” 

The sound of the MRI machine fades slowly as the surgery winds to a close. Once Peter’s body is completely free from the machine the cage that held his head perfectly still is removed and he is helped up from the table and into a waiting wheelchair, ready to take him away to the ward.  
The hand that meets Gilbertson’s when he reaches down to greet Peter after the surgery is strong, firm and still.  

The tremor is almost completely gone.  

“Peter did very well,” says Gilbertson. “He’s using his right upper limb well. Prior to the procedure he wouldn’t have been able to use his hands to feed himself or to drink from the cup and he was unable to write. All of those functions are now restored.” 

Logging onto a Zoom call the week after the surgery, Peter is a man transformed. His smile beams through the screen and as he holds his hand up to the camera, it’s rock solid with barely any movement.  

“It feels surreal,” says Peter. “I can use both hands now. I just can’t believe all this is happening and I’m feeling fine. I can use my knife and fork, I can clean my teeth better and I can shave. It’s things that you never even think about. The difference now is that I can do things. I can do things without having to say, ‘no, I can’t do it’. I can go and make a cup of tea or drink a glass of water without having to think about it and that’s the difference.” 

Peter’s voice, which before the surgery was quiet and almost non-existent at times, is clear and strong now. 

“It’s certainly been life changing,” says Peter. “I can feel since last week, since I’ve had the treatment, everything’s settling down again and it’s a lot better than how it was before.” 

The surgery has given Peter his confidence back, freeing his body from the constant pressure that a tremor brings and granting him the rest he so desperately wanted.  

“It’s like we’ve got a purpose again,” says Margaret. “It’s not that there wasn’t a purpose before, because there’s always a purpose in life. But without all these exceptional people who did the surgery, Peter would not be able to do what he is doing today. And that’s something we’ll forever be grateful for.”