Laser beam surgery (LITT) – your questions answered

Laser interstitial thermal therapy – known as LITT – is a treatment for epilepsy that uses heat from a laser beam to destroy damaged areas of the brain that cause seizures.

This treatment is also sometimes known as laser ablation surgery, and can be used as a less invasive alternative to open skull surgery.

The treatment promises a speedier and less painful recovery, and offers fewer cognitive problems afterwards compared to more typical epilepsy surgery.

We spoke to Mr Farah to learn more about this treatment.

Can you tell me a bit about the LITT treatment?

The operation is a form of ablation. Once brain tissue has been identified as a focus of epilepsy (an area where seizures start from), it is possible to burn it away with a laser probe.

The probe is delivered through a twist drill and then is inserted into the focus. The laser ablation can be used in cases such as hypothalamic hamartoma (a non-cancerous tumour in the hypothalamus) in the UK.

Who is eligible for this treatment?

This treatment is only available for people with focal seizures, and the maximum seizure focus size that can be ablated is 3cm.

It is not used for generalised epilepsy at the moment, although there is a new way of doing a corpus callosotomy (where a band of fibres connecting the two halves of the brain are cut), but I would say that this is still experimental.

How effective is this treatment?

It has been proven to be as effective as surgery in suitable cases. A meta-analysis of data from 16 studies that included 269 patients with treatment-resistant epilepsy showed that MRI-guided LITT significantly reduced the frequency of seizures and reduced postoperative complications. This supports the safety and effectiveness of MRI-guided LITT in the treatment of drug-resistant epilepsy.

What further research do we need in the UK on it?

In the UK, research is limited at the moment. Practically, in the UK, we need to build up the experience as our experience is mainly on hypothalamic hamartoma, which is only one indication. But looking at temporal lobe (with a seizure focus in the temporal lobe) and extratemporal lobe epilepsies (with a seizure focus outside of the temporal lobe), our experience is limited, I would say.

We can utilise the research from the US, as they use the treatment a bit more widely. I wouldn’t personally consider LITT an alternative to surgery at this moment in time, because the evidence that there is from the US is not strong enough in certain aspects. There are no specific restrictions on what can be treated with LITT in the UK. At the Walton Centre we decided to treat focal epilepsies related to conditions difficult to treat with open surgery, or linked with higher surgical risks of complication. I think that’s a more appropriate approach to it.

Where is the treatment currently available?

This treatment is available on the NHS in Liverpool at The Walton Centre, and in London at Kings College Hospital for adult epilepsy.

For paediatric epilepsy, it’s available in four centres, including Alder Hey, Bristol Royal Hospital for Children and Great Ormond Street Hospital.

However, everyone can be referred within the country, it is very much open. I encourage a referral system from epilepsy services. In other words, it’s important to identify the seizure focus, and the work up to surgery in epilepsy is quite long. I think this should be done at the local unit, and any appropriate cases can be referred to us and I would be very happy to provide the treatment.

For a patient, what does a day look like coming in for this treatment?

This is a minimally invasive treatment, in the sense that it will substitute a full craniotomy (open skull surgery). These cases are sometimes done as day cases, or possibly with a 24-hour hospital stay. The patient signs a consent form and undergoes general anaesthesia. I then place a static frame, I do a registration and then will place the laser probe using a robotic arm for precision. Then I will verify the position of the laser probe and after I verify the position, we go into the MRI scanner and the treatment is delivered within the MRI scanner with the patient asleep.

The ablation and the treatment probably lasts about half an hour. Then the patient has a scan to verify the ablation and then we remove the laser probe and the patient is woken up.

At the moment, we’re keeping patients for 24 hours after the procedure. In the future, I think we’ll go down the route of a day case and therefore we will discharge the patient on the same day.

What’s the aftercare and recovery like for patients?

There isn’t really any sort of scar and there is no hair shaving. The only thing is just a small entry point where a single suture (stitch) is applied.

People are observed in recovery for a few hours and then the patient goes to the ward or goes home.

The only problem could be oedema (a build up of fluid) and swelling. The swelling is the biggest issue, and will occur post operatively within a week. Generally, this is controlled with steroids, so we send the patient home with steroids to take. It lasts between six and eight days and resolves progressively.

Can you have the procedure done more than once?

It can be repeated and it can be staged. There are a lot of options on that. For example, if you want to treat a 3cm area and then you realise that you’ve actually only ablated 2cm, you can re-treat the patient. Or, if you want to treat a 6cm area, you can stage the treatment over two LITT procedures, so you can treat a 3cm area first and then a second 3cm area next time. This is possible as well.

Can patients be weaned off their epilepsy medicines after having the treatment?

The same applies to patients getting LITT as with patients undergoing open surgery. On other words, you can get seizure freedom on and off medication. The best success and outcome would be seizure freedom off medication. But you can also be seizure free and stay on medication.

That means it’s the choice of the patient whether to stop the medication. Several patients will not want to stop their medication, particularly adults, due to the potential risk of losing their driving licence.

The normal procedure is that we would attempt to stop the medication within one year from the treatment, because if a patient has been seizure free for one year, they would be reluctant to stop their medication and risk losing their driving licence.

From my experience, about 50% of my patients who are completely seizure free would say that they prefer to stay on medication, but the target would be to make patients seizure free off medication.

Are there waiting lists for this treatment at the moment?

On my books, I have about five patients waiting, so the list is not particularly long. There is a longer wait for the investigations within the epilepsy surgical programme. You need to identify a focus where seizures are coming from and all those investigations, and the epilepsy programme itself will have a longer wait time.

What are the next steps for this treatment?

In the longer term, possibly in the next three to five years, I would expect that each major epilepsy service within the UK will offer this treatment and I wouldn’t expect that the whole of the North of England would be covered by one single centre. But I would not expect that every single new surgery unit would have this as a treatment option, I think this will depend on how big the epilepsy programme is.