Consultant neurologist Prof Richard Walsh outlines the progress achieved recently in conducting Deep Brain Stimulation surgery in Ireland to Michael McHale; typically, however, the service is starved of funds and personnel
For patients living with Parkinson’s disease, the impact of symptoms on their daily lives is a source of concern. But when the drugs they take to ease these effects begin to decline, worries can understandably rise further.
It is something seen often with the drug levodopa. Hailed as a game-changer in the treatment of the motor symptoms of Parkinson’s when it was first discovered, the treatment typically involves taking three pills over the course of a day. It is short-acting, requiring regular ‘top-ups’ so that patients can hopefully get through their day with few, if any, mobility issues.
Prpf Richard Walsh. Photo: David Coleman / BobbyStudio
However, as the disease progresses, the effects of the drug often lessen considerably. The brain’s ability to buffer the drug and produce its own dopamine diminishes. Prof Richard Walsh, consultant neurologist at Dublin’s Mater Hospital, describes the result of this effect as a ‘rollercoaster’ of drug response.
“They take their drug, they may wait half-an-hour, they can move like they don’t have Parkinson’s for two hours, maybe even three hours.
“But then it wears off and they’re watching the clock because they know they need another dose. They’re shuffling. Their tremor comes back. They’re stiff. They’re asking for help. And at their next dose, they wait half-an-hour and boom – off they go again.”
It is at this stage of advanced motor symptoms that Deep Brain Stimulation (DBS) is often considered. The procedure involves a surgically implanted electrode into the brain to deliver carefully controlled electrical stimulation to the specific structures that control movement and muscle function. The stimulation can be adjusted as a patient’s condition changes over time and, unlike medication, can offer long-lasting relief from debilitating symptoms.
After several years of patients having to travel abroad – mostly to the UK – for the procedure, the treatment is now available in Ireland through the Deep Brain Stimulation National Service, located in Dublin’s Beaumont and Mater hospitals, which opened in November 2021.
The surgery itself is completed in Beaumont, while the Mater’s specialists take the lead on pre-operative and post-operative care, which includes the ‘switching on’ of the electrode six weeks after surgery.
However, huge demand has already led to a lengthy two-year waiting list for the essential treatment here. To deal with this, many patients eligible for DBS are still being referred to the UK. While 20 DBS surgeries were carried out in Ireland in the first year of the Beaumont-Mater service, a similar number of Irish patients also travelled to the UK for the procedure during that time.
According to Prof Walsh, a lack of access to surgery is a major cause of delays in the service here. Since its inception, he says that the Mater has seen around 100 patients for pre- and post-operative care, but just over half of those patients have undergone their surgeries in Ireland.
“The bottleneck occurs in Beaumont Hospital where the access to theatre time is frustratingly limited. Catherine Moran is our functional neurosurgeon there and she is restricted to one or two surgeries per month.”
He expects the total number of DBS surgeries completed in Ireland since the launch of the national service to reach 60 by the end of this year, with the difference being made up through access to a private UK hospital.
Prof Walsh believes that, to meet the demand here in Ireland, national services would need to carry out between 50 and 60 surgeries each year. To do this, more resources would be required – both in terms of facilities and staffing.
“We need to boost the number of doctors, nurses and allied health professionals in the Mater as well. This year we’ll be doing as much as the top three centres in the UK in terms of volume, but we currently just have a half-time neurologist – that’s me – running the service. We’re victims of our own success.”
The road to establishing the national DBS service has been a long one. An initial health technology assessment by HIQA in 2012 lessened hopes that it would ever happen after it determined that a domestic setup would be more expensive per patient than the cost of sending people abroad for treatment.
However, organisations like the Neurological Alliance of Ireland stressed the burden that overseas treatment places on the patient, both in terms of travel costs and their own ability to take the journey.
In some cases, patients were unable to access the treatment because the travel required was too much for their condition to manage, something that Prof Walsh describes as having ‘an immediate chilling effect’.
“The money we’ve saved in the last three years must be in excess of €1million for the Exchequer in terms of trips over and back to the UK,” Prof Walsh added. Having a domestic service also removes significant levels of paperwork and management required to facilitate appointments and surgeries abroad, and the stress associated with patients having to book flights and accommodation, often at the last minute.
Recent research also shows the potential of DBS to help patients manage a range of other conditions. “DBS is going to really explode over the next 20 years in terms of alternative uses in epilepsy, mood disorders, psychiatric conditions – for example, obsessive compulsive disorder or refractory depression,” Prof Walsh believes. “We can now use DBS to modify brain circuitry, which is hugely exciting.”
Currently, however, the treatment is confined to patients with movement disorders, with striking results. “Some patients have returned to work after not having worked for 15 years because of tremor. It’s really quite transformative.”
The successful rollout of the DBS national service also points to the positive impact that hospitals combining their resources can have in delivering for patients.
“It’s a nice example of collaboration between Beaumont and the Mater,” Prof Walsh believes. “We’re always being told that we work in silos and don’t collaborate, but this is an example of expertise being shared across hospitals and – to give Beaumont and Mater executives credit – the courage to get on and put in the expertise needed to deliver a service and prove that it can be done.” 