National Hospital for Neurology and Neurosurgery Venous sinus stents (for the treatment of venous sinus stenosis and idiopathic intracranial hypertension) Lysholm Department of Neuroradiology
If you would like this document in another language or format or if you require the services of an interpreter contact us the Clinical Nurse Specialists directly. We will do our best to meet your needs. Contents What is venous sinus stenosis and idiopathic intracranial hypertension? 4 What is venous sinus stent treatment and how can it help? 5 What are the risks of venous sinus stent treatment? 5 What will happen if I choose not to have this treatment? 7 What alternatives are available? 8 How should I prepare for venous sinus stent treatment? 9 Asking for your consent 10 What happens during venous sinus stent treatment? 10 What should I expect after this treatment? 11 Where can I find more information? 12 References 13 How to contact us 13 Where to find us 14 2
This booklet has been written by the Department of Neuroradiology at the National Hospital for Neurology and Neurosurgery (NHNN). Our aim is to provide you with information about the use of venous sinus stents in the treatment of venous sinus stenosis and idiopathic intracranial hypertension (IIH). We will also tell you about alternative treatments of IIH. This booklet is intended for use by patients (or their families and carers) who may be offered this treatment. If you have any questions about any information in this booklet please do not hesitate to contact a member of the team caring for you. They will be happy to answer any question you may have. 3
What is venous sinus stenosis and idiopathic intracranial hypertension (IIH)? Venous sinus stenosis is a narrowing of the large veins (the venous sinuses) on the surface of the brain. These veins drain the blood from the brain. Narrowing or stenosis in these sinuses is commonly seen in IIH. IIH is a condition where the pressure inside the head is higher than normal without a clear cause, such as a tumour. The exact causes of IIH are not fully understood. All treatments are aimed at reducing the pressure. It is not clear whether the stenosis results in the raised pressure or the stenosis is caused by the raised pressure. IIH is quite rare and most patients get better after a few months on medication or by draining a small amount of cerebrospinal fluid (CSF). This is done by inserting a needle into the space around the spine. Draining CSF in this way is called a lumbar puncture (see alternative treatments). IHH can cause headache. In some cases, the headaches can be prolonged and become very severe and disabling. In extreme cases, the pressure on the nerves at the back of the eyes can lead to blindness if left untreated. 4
What is venous sinus stent treatment and how can it help? A stent is a tiny tube made of a metallic mesh. It is placed into the blood vessels to open up the narrowing and improve blood flow. There is growing evidence that opening up the narrowed vein can reduce the pressure inside the head and relieve the symptoms, often permanently. What are the risks of venous sinus stent treatment? All treatments and procedures have risks and we will talk to you about the risks of venous sinus stents. The procedure will take place under a general anaesthetic. Your anaesthetist will discuss the risks of general anaesthesia with you. Risks associated with the procedure and the use of venous sinus stents are: 5
Exposure to x-rays: The use of X-rays during the procedure presents a very small risk of temporary hair loss. Our state of the art imaging equipment ensures the radiation dose is as low as possible. It is important to tell your doctor if there is a possibility you may be pregnant. Allergic reaction to contrast dye: A contrast dye is injected into the arteries during the procedure to show up the blood vessels on x-ray. There is a small risk of an allergic reaction to the dye, or damage to kidney function. We take appropriate precautions in all patients who at risk to avoid this. Increased risk of bleeding: You will need to take tablets to make the blood less likely to clot in the days leading up to the procedure and for many months afterwards. These tablets can increase the risk of bleeding in other areas of the body and can irritate the stomach. It is important to tell your consultant if you have had a stomach ulcer in the past. Haematoma (large bruise) in the groin: Bleeding and bruising in the groin after the tubes are removed is unusual and rarely serious. Risk of stroke: The placement of a stent, like all procedures involving the blood vessels of the brain, carries a small risk of stroke caused by a bleeding or a blocked blood vessel. This can range from a minor problem which gets better to a severe disability involving movement, balance, speech or vision or even death. 6
On our current evidence, we would estimate that less than five people in one hundred will have a complication like this. The problem is almost always apparent during or immediately after the procedure or within the next few days whilst you remain in hospital. The stent devices we are using have been used elsewhere in the body for over 20 years with good long-term results. Their use in the venous sinuses is quite new and therefore we do not yet know how they will behave in the long term. On the basis of experience in other hospitals around the UK and the rest of the world, delayed problems seem to be very rare. What will happen if I choose not to have this treatment? The decision to offer you a venous sinus stent will have been discussed and agreed as the best course of treatment by a multidisciplinary team of neuro-radiologists, neurosurgeons and neurologists. If you are unhappy about the treatment being offered, a further full discussion with members of the team can be arranged. It is important that you fully understand the procedure, the risks and benefits and any alternative treatments available. There is clearly no obligation to follow the advice given. A decision not to choose this treatment will not affect any other aspect of your care. Also, it is entirely reasonable to seek a second opinion if you still have concerns. 7
What alternatives are available? Usually treatments for IIH are offered according to the severity of the symptoms. They are offered in the following order: Medication A medicine called acetazolamide is the most commonly used first line treatment. This is often effective, but side effects are quite common and often limit its use. Lumbar puncture For patients with rapidly progressive symptoms who do not respond to tablet treatment, the pressure in the head can be reduced by drainage of some of the fluid around the brain and spinal cord. This is done by passing a fine needle through the back into the lower spine to drain cerebrospinal fluid (CSF). This probably will already have been performed at the beginning of your treatment to confirm the pressure is indeed raised. Neurosurgery For a longer term solution, there are two surgical options: Optic nerve sheath fenestration is performed if loss of vision is the main problem. The skull is opened and a hole is made in the sheath (covering) around the nerve at the back of the eye to relieve the pressure here. CSF-shunting procedures are performed where headache is the main symptom. A tube is passed through the skull into one of the fluid spaces within the brain under a general anaesthetic to drain the CSF and relieve the pressure. 8
Both operations carry the risks of general anaesthetic, damage to brain or nerves during the procedure or subsequent infections. It is likely that these other treatments will be have been considered or perhaps previously performed without completely solving the problems. How should I prepare for venous sinus stent treatment? You may need to take tablets to reduce blood clotting for a number of days before the procedure. The doctors caring for you will advise you. You should take all your other medications as normal. You will usually be brought into hospital either the day before or on the morning of your procedure. You will meet your anaesthetist and neuro-radiologist before the procedure. The procedure is performed under a general anaesthetic (this means you will be unconscious or asleep throughout). Your anaesthetist will talk to you about the anaesthetic, pain relief and what you can expect when having a general anaesthetic. You will need to fast for some hours before your procedure and your anaesthetist will confirm with you what time you must stop eating and drinking. You should still take all of your medications at the normal times throughout this period with a sip of water. 9
Asking for your consent 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. A member of staff, usually the nurse caring for you, will accompany you to the radiology department. What happens during venous sinus stent treatment? The procedure is performed by a neuro-radiologist, in an operating theatre located in the radiology department. It usually takes between one and three hours. A dedicated team of radiologists, radiographers, anaesthetists and nurses will be in the operating theatre. They will be monitoring you closely throughout the procedure. After the anaesthetic has commenced, the neuro-radiologist uses an X-ray camera guidance to pass a thin, flexible, plastic tube (catheter) into the femoral vein. This is the large vein in the groin. The catheter is passed up through the body, through the heart and into the jugular vein in the neck. 10
A second smaller catheter is inserted inside the first, past the narrowing in the vein. The collapsed stent is pushed through the tip of the smaller catheter. The catheter is then pulled back to allow the stent to expand in the vessel. Sometimes it is necessary to inflate a tiny balloon in the vein to open the narrowing. Often this immediately reduces the pressure inside the head, sometimes it can take a few days to settle. Once the radiologists are satisfied with the result, all the tubes are removed, leaving just the stent in the vein. You will be moved to the recovery ward where you will be closely monitored as you recover from the anaesthetic. Afterwards you may spend some time in the high dependency unit for monitoring and control of your blood pressure and to ensure you are recovering as expected. What should I expect after venous sinus stent treatment? You will be in hospital for a minimum of three to four days after procedure; until you are walking around and feeling back to normal. You should plan to take a few weeks off work and have someone at home with you for the first few days after you leave hospital. It is common to experience headaches in the days or weeks afterwards. You will be given pain killing drugs to help with this. 11
If this headache becomes severe or you experience nausea, vomiting, drowsiness or severe stiffness in your neck you should go to your nearest Accident and Emergency Department (A& E, Casualty) where a CT scan will be performed. The local A & E doctors will contact us for further advice. For any other issues, you should contact the Neurovascular Specialist Nurses. The stent itself will remain in your body for the rest of your life. It will gradually be covered by the normal linings inside the vein over time. It will not set off metal detectors at airports and is safe for you to have an MRI scan of any part of the body, including the brain. Where can I get more information? The Brain and Spine Foundation Telephone: 0808 808 100 http://www.brainandspine.org.uk/helpline/ http://www.iih.org.uk/iih.php UCL Hospitals cannot accept responsibility for information provided by other organisations. 12
References http://www.iih.org.uk/iih.php How to contact us Neurovascular Clinical Nurse Specialists The National Hospital for Neurology and Neurosurgery Queen Square London WC1N 3BG Direct line: 020 3448 3523 Switchboard: 0845 155 5000 / 020 3456 7890 Extension: 83523 Email: neurovascularnurse@uclh.nhs.uk Website: www.uclh.nhs.uk/nhnn 13
Where to find us 14
Space for notes and questions 15
First published: October 2010 Date last reviewed: March 2018 Date next review due: March 2020 Leaflet code: UCLH/NHNN/NRAD/VSS /PIL03 University College London Hospitals NHS Foundation Trust 16