This is a brief summary of what laser interstitial thermal therapy involves for a patient, and is intended for patients and their carers/families. It is intended for patients who are considering consenting to this treatment.
Neurosurgery is a treatment option for some people with epilepsy. In order to decide whether it may be helpful for you, we need to consider the following:
- You have tried two or more anti-epileptic drugs, but these have not been suitable or successful in stopping seizures.
- Investigations show that your epilepsy comes from one area of your brain.
- The surgeon can access this area and can remove it without damaging important brain functions, such as speech, sight, movement, hearing, or memory.
- You have no other medical problems, which would make neurosurgery dangerous.
- We believe that surgery has a good chance of stopping or improving your seizures. Since 1990, over 1,000 individuals have had neurosurgical treatment for their epilepsy at the National Hospital for Neurology and Neurosurgery (NHNN) at Queen Square.
Laser interstitial thermal therapy (LITT) is a new form of minimally invasive surgical treatment for epilepsy. This involves the use of a specialised laser catheter through a small hole made in the skull to treat the part of the brain that is causing seizures with heat, without the need for open surgery. This is a treatment that has been widely adopted in the USA as well as across Europe, in over 3,000 cases.
You are being given this leaflet because your team of doctors and surgeons feel it is the most appropriate for you, and so it is important for you to understand why we are offering this and what it will involve. Please take time to read the following information carefully and discuss it with others if you wish. Ask us if there is anything that is not clear, or if you would like more information. The following pictures demonstrate what the laser catheter looks like (Fig. 1) and how this looks when implanted (Fig. 2).
Figure 1: The appearance of the laser catheter that is implanted to deliver LITT.
Figure 2: An example of how the implanted laser catheter appears.
Compared with traditional open surgery, laser interstitial thermal therapy is a less invasive ‘keyhole’ approach to surgery to the area of the brain that we think is causing your seizures, we will make a smaller opening in your skull, and you are likely to have a shorter stay in hospital after the procedure.
All treatments and procedures have risks and we will talk to you about the risks of LITT in appointments with your surgical team.
Possible risks of any neurosurgical procedure:
Infection, pain, brain swelling, bleeding into the brain and over the brain’s surface, stroke and worsening seizures.
Complications such as infection, bleeding or stroke can rarely be very serious and lead to a permanent loss of function (for example weakness and loss of sensation in the face and limbs, difficulty with speech or understanding speech or written words, worsened memory, loss of part of the field of vision).
Complications associated with operating the thermal therapy system – improper machine operation, inaccurate fibre placement, and failure of the cooling mechanism around the catheter leading to damage to the brain caused by the heat delivered by the laser.
The risks will vary according to the part of the brain that needs to be treated, and your surgeon will discuss these more in details with you in clinic well in advance of you accepting the procedure.
The procedure is performed under general anaesthetic, and this carries risks of infections of your chest and urine, as well as risks of clots in your legs and lungs. You will have the opportunity to discuss these risks with the anaesthetic team both at a pre-assessment appointment as well as before the surgery when you are in hospital. These are standard risks for general anaesthetic, and will be managed, for example by wearing surgical stockings and with careful monitoring.
It is your decision whether you consent to go ahead with this procedure or not, and we will continue to treat you in the best of our abilities regardless of your decision. This is being offered to you as we feel it is the best course of action in your particular case.
Alternative treatment options are always specific to each individual case, but in general would include having no surgical intervention, and continuing with your current medical treatment, or to have a different form of surgical treatment, such as an open surgical resection, the risks and benefits of which will be discussed with you by the surgical team, and are detailed in a separate patient information leaflet.
What do I have to do before going into hospital?
It is important to carefully plan your admission and convalescence, with help at home for the first few weeks. You should not expect to be able to resume work for at least three to five weeks. We would recommend going back firstly on a part-time basis.
We might ask you to come to a pre-assessment clinic at NHNN in the weeks before your surgery to make sure that there are no concerns with your general health, which would make surgery or the anaesthetic riskier.
What happens just before the operation and consent?
We will admit you to hospital on the morning of surgery, or one or two days beforehand, if more tests are needed. The day before or on the morning of surgery, you will normally have an MRI scan, to guide and make your operation safer. The neurosurgical staff will meet you and ask for your written consent for surgery.
Before the operation
The night before, or on the morning of surgery, you will need to wash your hair. At the time of surgery, we will shave the hair where we will make the incision on your head, and will mark your skin with ink. Your hair will quickly re-grow afterwards.
The anaesthetist will explain to you what the anaesthetic will involve. You will not be allowed to eat or drink for about six hours before surgery but you will receive your anti-epileptic medication as usual.
Operations can vary in duration between four to eight hours, according to which part of the brain will be treated with the laser.
Your family can ask the nursing staff when they think you are ready for visits or calls. If a close relative prefers to be at NHNN at the time of surgery, they may tell the ward sister where they will be so that a member of the operating theatre staff can let them know how you are.
We want to involve you in all the decisions about your care and treatment. If you decide to go ahead with treatment, by law we must ask for your consent and will ask you to sign a consent form. This confirms that you agree to have the procedure and understand what it involves. Staff will explain all the risks, benefits and alternatives before they ask you to sign a consent form. If you are unsure about any aspect of your proposed treatment, please don’t hesitate to speak with a senior member of staff again.
The surgery itself is split into two phases – the insertion phase and the ablation phase.
The insertion phase is the image-guided insertion of the specialised laser catheter through a small hole in the skull, which is done by the surgeon in the operating theatre while you are asleep under general anaesthesia.
Once this is done, we move you to the MRI scanner, where we will first scan to double check that the laser catheter is in exactly the right place. We then enter the second phase of the procedure, which is performed while you are asleep in the MRI scanner. This phase involves targeting and treating with heat the tissue causing your seizures by using the specialised software in the laser device to heat the tip of the implanted catheter. The surgeon can monitor in real time exactly how much heat is applied to exactly which part of the brain.
When this is done, we are then able to scan again to ensure we have treated as much as we need to, and the procedure is complete. You would then return to the operating theatre (still asleep from the same general anaesthetic) and have the catheter removed and the surgical wound closed.
There will be a very small skin incision and opening in the skull, so it is likely that you would be safe to go home within one to two days after the operation.
How will I feel when I wake up?
After the operation, you will wake up in the Recovery Ward. We will give you regular painkillers and tablets to stop you feeling sick. You may spend the first 12-24 hours after surgery in the High Dependency Unit (HDU) or Overnight Recovery to enable us to keep a close eye on you. It is usual to wake up with a headache. The staff and nurses are very experienced with surgical patients and the medical staff will visit you each day.
During the first few days, you are likely to feel very tired and sleepy, because of the anaesthetic. You may have good days and bad days - this is normal. Please keep visitors to a minimum. They must be free of coughs, colds, upset stomachs, or other infections. Young children should only visit after discussion with the nursing staff and must be accompanied by an adult.
Seizures may occur within the first week after surgery and this does not mean that the surgery has been a failure. We will check your medication and possibly adjust it. When we are happy that you are making an adequate recovery, you can return home. This is usually five to six days after the operation.
What about care of my wound?
We usually close the cut on your head with stitches or clips, which are removed seven to eight days after surgery. Your wound needs to remain dry until the stitches are removed.
You can wash your hair after the stitches are removed. You should treat the wound with care during the first few weeks, avoiding vigorous shampooing or brushing. Please avoid scratching your wound. If you experience any discharge of fluid from the wound, or if you are worried about it, please contact the surgical team through their secretary (020 3448 3393), or ask your GP to contact the surgical team.
What about my recovery and returning to exercise?
During the weeks following surgery, it is important to rest. It is usual for you to tire very easily. Building up physical and mental activity slowly over the weeks will help.
When can I have sex after surgery?
As soon as you wish, provided that you feel physically and mentally ready.
Recovery at home after surgery
The after-effects of an anaesthetic may take a long time to wear off. For each hour of anaesthetic, you may take a week to feel entirely normal. So, for a three-to-four-hour anaesthetic, it may take three to four weeks before you feel your energy returning to normal.
Try to drink plenty of fluids, eat regular meals, and sleep when you wish to. You should build up activity slowly and try to spend part of each day up and about. You may start going for short walks when you feel up to it. Try to gradually build up your walking activity each day. Your aim should be to be back to almost normal activity by two weeks following the operation.
When will I have my next appointment?
We will arrange an appointment with the surgeon and your neurologist usually eight to 12 weeks after surgery. An MRI and memory tests will be carried out three to four months after surgery. We will probably not alter your medication for at least a year after surgery. You will also have a further assessment with the neuropsychologists one year after surgery. We may recommend a further MRI and EEG at this time. If there are concerns about your mental health, we will arrange for you to see a psychiatrist.
Driving and the DVLA regulations
The DVLA regulations state that you must be seizure-free for at least a year before you are eligible to hold a private car or motorcycle driver’s licence.
If you are seizure free and your medication is stopped, there is a higher risk of seizures recurring and you and your consultant would need to give this careful consideration. During the tapering of the last medication and the subsequent six months, you are advised not to drive, even if no seizures have occurred. If any seizures did occur when medication was being tapered, you would have to wait again until you have had no seizures for six months and had effective doses of medication restarted, before restoration of your driving licence.
The DVLA also require you to have a visual field test to ensure that it is safe for you to drive. This can be arranged at the Sir William Gowers Centre at NHNN or by most opticians.
How soon may I travel after surgery?
We advise against air travel in the first two to three weeks, unless a brain scan has shown there is no air inside your head. After the initial few weeks of convalescence, there is no reason why you should not travel by land, sea or air.
When will I know if surgery has been successful?
Before surgery, the medical team will have carefully discussed the aims of the operation with you. In many cases, this is to completely stop the seizures; in others, it is to reduce the number or severity of seizures. Whatever the aims of surgery, these will usually have been achieved within two years.
It is important to realise, however, that not having seizures may lead to other problems and stresses in daily life and therefore contact with your neurologist, psychiatrist and / or psychologist may need to continue for some time after this period.
Long-term follow-up
We have carried out epilepsy surgery at NHNN since 1990 and it is important for us to know how you get on in the long term. If you are no longer being seen at the hospital, we would like to write to you, your GP, and local neurologist on a yearly basis for an update on how you are getting on.
Unfortunately, there is never any guarantee that surgery is going to be completely successful. If surgery is not successful, we may decide to reinvestigate you after a few months, to see if there is a possibility of further surgery being helpful.
If you wish to know more details about the proposed treatment, you may be interested in some of the below papers. These are primarily for a medical scientific audience and so do contain quite a lot of complex medical terminology and language:
- Grewal S., Alvi MA, Lu VM et al. (2019) Magnetic resonance-guided laser interstitial thermal therapy versus stereotactic radiosurgery for medically intractable temporal lobe epilepsy: A systematic review and meta-analysis of seizure outcomes and complications. World Neurosurgery (122) e32-e47.
- Xue F, Chen T and Sun H (2018) Postoperative outcomes of magnetic resonance imaging (MRI)-guided laser interstitial thermal therapy (LITT) in the treatment of drug-resistant epilepsy: A meta-analysis. Medical Science Monitor (24) 9292-9.
- Wu C, Jermakowicz WJ, Chakravorti S et al. (2019) Effects of surgical targeting in laser interstitial thermal therapy for mesial temporal lobe epilepsy. A multicentre study of 234 patients. Epilepsia 60:1171-1183.
- Drane DL. (2018) MRI-guided stereotactic laser ablation for epilepsy surgery: promising preliminary results for cognitive outcome. Epilepsy Res. 142: 170–5.
- Zubkov S, Del Bene VA et al. (2015) Disabling amnestic syndrome following stereotactic laser ablation of a hypothalamic hamartoma in a patient with a prior temporal lobectomy. Epilepsy & Behavior Case Reports (4) 60-2.
- Barber SM, Tomycz L et al. (2017) Delayed intraparenchymal and intraventricular haemorrhage requiring surgical evacuation after MRI guided laser interstitial thermal therapy for lesional epilepsy. Stereotactic Functional Neurosurgery 95; 73-8.
- Lewis EC, Weil AG, Duchowny M, Bhatia S, Ragheb J, Miller I. MR-guided laser interstitial thermal therapy for pediatric drug-resistant lesional epilepsy. Epilepsia. 2015 Oct;56(10):1590-8. doi: 10.1111/epi.13106. Epub 2015 Aug 7. PubMed PMID: 26249524.
- Ellis JA, Mejia Munne JC, Wang SH, McBrian DK, Akman CI, Feldstein NA, McKhann GM. Staged laser interstitial thermal therapy and topectomy for complete obliteration of complex focal cortical dysplasias. J Clin Neurosci. 2016 Sep;31:224-8. doi: 10.1016/j.jocn.2016.02.016. Epub 2016 May 24. PubMed PMID: 27234607.
- Esquenazi Y, Kalamangalam GP, Slater JD, Knowlton RC, Friedman E, Morris SA, Shetty A, Gowda A, Tandon N. Stereotactic laser ablation of epileptogenic periventricular nodular heterotopia. Epilepsy Res. 2014 Mar;108(3):547-54. doi: 10.1016/j.eplepsyres.2014.01.009. Epub 2014 Jan 30. PubMed PMID: 24518890.
- Wicks RT, Jermakowicz WJ, Jagid JR, Couture DE, Willie JT, Laxton AW, Gross RE. Laser Interstitial Thermal Therapy for Mesial Temporal Lobe Epilepsy. Neurosurgery. 2016 Dec;79 Suppl 1:S83-S91. Review. PubMed PMID: 27861328.
It would be helpful for you to note down the names and contact details of the specialists involved in your care so that it is easier to make contact should you need to.
Your Hospital Number: ................................................................................
(Can be found on any correspondence you receive from us.)
Neurologist: ..................................................................................................
Epilepsy nurse specialist advice line (office hrs only):
............................................................................................... 020 3448 8627
Epilepsy nurse specialist email
....................................................................................uclh.epilepsy@nhs.net
Epilepsy surgery coordinator: ............................................ 020 3448 8616
Epilepsy fax no: ................................................................... 020 3448 8615
Neurosurgery (secretary) ................................................... 020 3448 3393
On-call neurosurgery SpR ............................... 0845 1555000, Bleep 8100
Psychologist: ................................................................................................
Psychiatrist: .................................................................................................
Postal address:
Epilepsy Department
Box 29
National Hospital for Neurology and Neurosurgery
London, WC1N 3BG
https://www.uclh.nhs.uk/epilepsy
