Aretaeio Hospital
Andrea Avraamidi 55-57, Strovolos 2024, Nicosia,
Cyprus
Contact
Email: consulting at ncir.com.cy
Phone: +357 99 44 08 22
Interventional radiology (IR) is a radiological subdiscipline providing minimally invasive treatments performed under image guidance. As technology advances and high-quality imaging equipment becomes more widely available, IR is able to offer patients and referral physicians a growing number of new treatment options.
What is percutaneous tumour ablation?
Percutaneous tumour ablation refers to a range of techniques which destroy tumour tissue via needles placed through the skin. Some techniques use chemical agents (such as absolute ethanol), while others use physical agents, which may be thermal (using heat) or non-thermal. Thermal ablation techniques destroy tumours by using different kinds of applicators to freeze the tumour (called cryoablation) or to heat the tumour, such as radiofrequency ablation, laser ablation, microwave ablation and high-intensity focused ultrasound (HIFU).
Non-thermal ablation techniques use other sources of energy to achieve tumour destruction. Coblation uses an electrical plasma field to disintegrate the tissue by rupturing the bonds between the molecules which make up the tumour tissue. Irreversible electroporation uses high voltage electric shocks to pierce the cell membranes and cause cell death.
How does the procedure work?
The procedure will be carried out using image guidance, such as ultrasound, CT or MRI, to control the insertion of the devices and the energy deposition. You will be anaesthetised for the procedure. For most ablation procedures, the interventional radiologist will insert one or more needles or applicators into your tumour to deliver the chemical agent or physical energy.
Why perform it?
The goal of tumour ablation is to destroy the tumour without using surgery. Whether you are suitable for this procedure depends on the size and location of the tumour as well as your clinical situation.
What are the risks?
The insertion of the needle or applicator may cause bleeding or puncture surrounding organs. Another risk is the accidental leakage of the chemical agent or uncontrolled depositing of radiation energy, which may cause serious damage to the surrounding tissues.
What is angiography?
Angiography (also known as arteriography) is a medical imaging technique which is used to visualise the inside of your blood vessels, particularly the arteries.
The procedure is carried out by an interventional radiologist, who will inject a radiopaque contrast agent into your blood vessel. This is a substance which will make your blood vessels show up more clearly under imaging. The interventional radiologist will use fluoroscopy for image guidance.
A diagnostic arteriogram is a procedure which involves inserting a needle or catheter into an artery, followed by injection of a contrast agent and then observing the area via imaging.
How does the procedure work?
You will have a local anaesthetic for the procedure. The interventional radiologist will insert a catheter and guidewire into the affected area and will inject the contrast agent so he can visualise the anatomy of your artery and the disease. Occasionally, the interventional radiologist will need to access the artery through your common femoral artery (CFA), which is in your thigh.
Why perform it?
You may be advised to have a diagnostic angiography if your doctor suspects that you have vascular disease, particularly acute pulmonary embolus (a mass which moves around your body and may clog an artery), and other tests have been unclear. A diagnostic angiography can also be used to diagnose and localise a hypervascular tumour (a tumour with a large number of arterial blood vessels).
A further possible reason to have an angiography is as a pre-operative procedure, meaning your doctor would like a more detailed knowledge of your anatomy, as this knowledge is beneficial for procedures such as revascularisation (restoring blood to an area with a restricted blood supply), local tumour resection (surgically removing a tumour) and organ transplantation.
A diagnostic angiography also aids with diagnosis and treatment of post-operative or traumatic complications. It can also be used during procedures such as thrombolysis, angioplasty, stenting and embolisation as it gives the interventional radiologist performing the procedure a clearer view of what they are doing.
What are the risks?
There are a number of possible risks. You may have bruising, a pseudoaneurysm (when a bruise forms outside an artery wall) or a blood clot.
Systemic complications are complications which affect the rest of your organ systems. These occur in less than 5% of cases, and include nausea, vomiting and fainting. In less than 1 in 1000 cases, patients experience a life-threatening reaction to the contrast agent. Mortality associated with the contrast injection occurs in less than 1 in 120,000 cases and this is usually related to underlying factors, such as severe congestive heart failure, major trauma and general weakness.
Individuals react to the contrast agent in different ways, and it is possible you will experience hives, puffy eyes or wheezing, though these complications occur in fewer than 3% of angiographic procedures. Most reactions are mild, with more than half not needing any therapy at all and less than 1% requiring hospitalisation.
When less strong agents are used, there are fewer reactions. Agents that are more diluted tend to be used in patients with a history of reacting to contrast agents or patients who have more than one other major risk factor.
What is angioplasty and stenting?
The arteries supplying your head, heart, kidneys and legs may become blocked over time because of smoking, high cholesterol, high blood pressure, diabetes and obesity. These can cause a progressive hardening and occlusion of the vessels (also known as arteriosclerosis). Arteriosclerosis reduces blood flow to your organs as a result of the narrowed or obstructed arteries.
Interventional radiologists are recognised experts in vascular diseases, who can use a technique involving angioplasty and stenting to restore blood flow to the brain, kidneys and legs.
Angioplasty involves the mechanical dilatation of any narrowed or occluded vessel by means of a balloon catheter and a metal stent if necessary. Balloon catheters are tiny empty balloons which are gently inflated to expand the area. A stent is a metal mesh tube that is inserted over a metallic guidewire and positioned at the point of the stenosis or occlusion. Metal stents are permanent implants and act as mechanical scaffolds to support the vessel wall and keep the vessel open.
How does the procedure work?
You will have a local anaesthetic for the procedure. The angioplasty and stenting procedure will last around an hour and tends to be performed as an out-patient procedure, though in some cases patients are admitted to hospital overnight afterwards.
The interventional radiologist will puncture an artery in your thigh with a small needle and will then thread a combination of plastic tubes (called sheaths and catheters) into your arteries. Throughout the procedure, the interventional radiologist will use imaging for guidance. A balloon catheter will be inflated across the narrowed or obstructed part of the vessel; you may experience some discomfort at this point. In some cases, the balloon angioplasty is enough to keep the vessel open, but in other cases the vessel needs more support, so a stent is placed. This means the interventional radiologist will put a stent into the vessel to ensure it stays open.
Your vital signs will be monitored during and after the procedure, and you may be able to eat a light meal later the same day.
Why perform it?
This procedure may be beneficial for you if you suffer from leg pain when walking (intermittent claudication) or if you have a restricted blood supply in your legs (leg ischaemia) as a result of diabetes. The angioplasty and stenting procedure can also be a treatment for peripheral arterial disease and for narrowed or blocked arteries in your kidneys.
Angioplasty and stenting is a way to restore blood flow, relieve pain caused by restricted blood flow, improve kidney function and protect the brain from strokes.
What are the risks?
The success rate of the procedure is usually around 90-95%, though it varies according to the extent and complexity of the blockages in the artery. The majority of patients experience significant clinical improvement, meaning that their pain decreases and any wounds in the area heal better.
In around 10-15% of cases (the rate depends on the location and particular structure of the artery), the affected artery becomes blocked again, known as restenosis. If this happens to you, your symptoms will return and you will need to be treated again.
Minor complications are unusual but include bleeding, bruising and infection. In rare cases, patients have an abdominal haemorrhage, which requires a stay in hospital and patients may need blood transfusions. It is possible that the artery will be damaged by the balloon, causing the vessel to rupture, in which case the interventional radiologist will place a covered stent in the vessel to control any bleeding. The balloon inflation may cause small fragments from the blockage to break off and block other smaller vessels, causing the blood flow to be restricted even more. There is a very low risk of losing a limb or stroke, depending on the location of the artery on which the procedure is carried out.
Although the interventional radiologist will do all they can do minimise the risk of an allergic reaction, there is a risk of a reaction to the dye used in the imaging technique.
What is aspiration?
Aspiration is the image-guided puncture of a cystic lesion (such as a cyst, an abscess or bruising) or solid lesion (a growth) in order to remove a fluid or tissue sample with a suction needle. The hollow aspiration needles come in different sizes and lengths.
How does the procedure work?
If you are on any medication that prevents blood clotting, you should stop taking it before the procedure, if possible.
You should not eat anything for at least four hours before the procedure. You may be asked to fast for longer, depending on the puncture and whether the procedure is particularly complicated.
The interventional radiologist may use one of a number of image guidance techniques to plan and monitor the placement of the needle during the aspiration procedure, including ultrasound, CT, MRI and fluoroscopy. You will lie down for the procedure – the exact position you will be asked to lie in depends on the access route that the interventional radiologist will use to safely approach the lesion.
Aspiration is usually performed under local anaesthesia. You may be asked to take antibiotics beforehand to reduce the risk of infection, but this is uncommon.
The procedure will be carried out in a sterile and safe environment. The interventional radiologist will use image guidance to insert a needle until the needle tip is inside the lesion. The interventional radiologist will then insert a syringe to remove the sample or cyst.
Aspiration can be performed as an in-patient or out-patient procedure. The puncture site will be monitored for 2-4 hours to check for bleeding. You may experience some mild discomfort at the puncture site during the first few hours following the procedure.
Why perform it?
You may be recommended to have an aspiration procedure for diagnostic reasons (to provide information on the nature of the lesion) or for therapeutic purposes, such as removal of the fluid collection or cyst. Aspiration is sometimes preferred over drainage of small abscesses (less than 3-4 cm) for which a drainage catheter would be unsuitable.
Aspiration may not be the best option for you if you have a blood clotting disorder or there is no safe access route.
The technical success rate of this procedure is very high, though the clinical success rate can vary depending on the location and nature of the lesion, as well as whether the aspiration procedure is diagnostic or therapeutic.
What are the risks?
Fine needles are used for the procedure, making the complication rate very low. The most common side effects are bruising, infection, and, in the case of lung aspiration procedures, pneumothorax (the collection of air in the space between the chest wall and the lung).
If the aspiration was used to treat an abscess, you may experience procedure-related sepsis (widespread inflammation in the body), but the risk of this is lower than with drainage procedures.
What is BRTO?
Portal hypertension refers to high blood pressure in the liver. One of the major possible complications of portal hypertension is gastric variceal bleeding. Varices are dilated vessels which may rupture, causing variceal bleeding. Gastric variceal bleeding describes the bleeding that occurs when dilated vessels in the stomach rupture, and is associated with high morbidity and mortality rates.
BRTO is a minimally invasive technique that is used to treat gastric variceal bleeding. The procedure involves blocking the dilated vessels, reducing the risk of rupture. It can be used in addition to or as an alternative to TIPS, which is the primary treatment for gastric varices. TIPS aims to relieve the pressure on the dilated vessels by creating new connections between blood vessels in the liver using a shunt.
How does the procedure work?
The interventional radiologist will insert a balloon catheter (a thin, flexible tube with a tiny balloon at one end) through a vein in your thigh or neck and guide the catheter to the liver using fluoroscopy for guidance. The catheter is then directed to the gastrorenal or gastrocaval shunt and the balloon is expanded to block the shunt.
The interventional radiologist will then perform a venography, which is a type of imaging technique in which X-rays are used to see the vessels clearly. This will allow the interventional radiologist to confirm exactly which vessels need to be treated and if there are any other abnormal or dilated vessels which have not previously been identified. A medication will then be injected into the dilated vessels through the catheter, until they are completely filled. This medication will remain in the vessel for a short period of time, and will then be removed under fluoroscopy.
Another venography will then be performed, to confirm that the blood flow in the shunt has stopped. Finally, the balloon will be deflated and the interventional radiologist will withdraw the catheter.
Why perform it?
You may be advised to undergo this procedure if you are at risk of or already have gastric variceal bleeding and hepatic encephalopathy as well as a gastrorenal shunt. Hepatic encephalopathy refers to the worsening of brain function that is caused by a damaged liver.
Although TIPS has been considered the standard therapy for gastric varices that have been unresponsive to other treatments, recent reports have stated that BTRO is a less invasive and more effective way to manage varices than shunt surgery or TIPS. TIPS does not always cause the disappearance of gastric varices, while BRTO can in most cases completely destroy these vessels.
BRTO has tended to be used to prevent gastric variceal bleeding. It is also an effective therapy for sclerosis (narrowing) of new portosystemic shunts with the additional complication of hepatic encephalopathy. One of the greatest advantages of BRTO is its preservation of liver function. Moreover, the increase of blood flow in BRTO can also improve liver function in cases where the patient has cirrhosis (scarring of the liver).
What are the risks?
Procedure-related complications are minor and include bleeding and infection. In rare cases, the blockage of the blood to the gastric varices can further increase the pressure on the liver, causing damage to the liver.
The most serious complications of the procedure, however, are related to the medication used to block the vessels, which is called ethanolamine oleate. Inflow of a relatively large amount of ethanolamine oleate can lead to serious complications. These complications include pulmonary embolism (blockage in a lung’s main artery), fluid in or around the lungs, hypersensitivity, fever, problems with blood flow to the heart and the formation of small blood clots in vessels throughout the body. Ethanolamine oleate also causes haemolysis, which is the rupturing of red blood cells. To prevent this from occurring, only a low dose of the medication is used.
What are biliary procedures?
Percutaneous transhepatic biliary drainage (PTCD) is the placement of a drain into bile ducts using needles inserted through the skin. The procedure can be used to treat cholestasis (where the bile cannot flow from the liver to the small intestine), which may be a result of a narrowing or blockage in the bile ducts or of a bile leakage after an operation.
Biliary stenting is performed after biliary drainage if the blockage is malignant (cancerous) to keep the bile duct open and to allow the drain used in PTCD to be removed. This involves putting a stent (a mesh metal tube) into the bile duct, which then functions as a supportive skeleton to prevent the duct from closing.
Biliary stone extraction is carried out using percutaneous access to the biliary tree (also known as the biliary tract, this is the path by which bile travels from the liver to the small intestine). Stones can be removed using a tiny basket or with a grasping device. Small and medium-sized stones can be pushed into the first part of the small intestine using a tiny balloon. If the stones are larger than 5 mm, a tiny balloon is used to dilate the entrance to the small intestine.
How does the procedure work?
Puncturing the bile duct is usually performed under sedation and local anaesthesia, though in rare cases and depending on the patient’s underlying condition and age, the procedure may be carried out under general anaesthesia.
You will be given antibiotics beforehand to prevent infection. The procedure will be carried out in a sterile room while you lie on your back. The interventional radiologist will perform the procedure under X-ray guidance, though sometimes ultrasound is used in addition to fluoroscopy to confirm the direction for the puncture.
The interventional radiologist will pass a small needle through your skin into either your left or your right liver lobe. If it is the right liver lobe which is punctured, this will be between your ribs and in the middle of your side. If it is your left liver lobe which is punctured, the interventional radiologist will choose an entry site below the tip of your breastbone.
As the needle is withdrawn, the interventional radiologist will gently inject a diluted contrast agent, a substance which makes the area show up better under imaging. This means that, when the needle enters the bile duct, the tubular structure is more clearly visible under imaging. The interventional radiologist will then insert a guidewire into the bile duct, which is followed by a catheter. The guidewire and catheter are used together to move past the blockage and reach the intestine.
Once the interventional radiologist has removed this catheter, they will dilate the blocked liver tract so that the drainage catheter can be placed. A drainage catheter has multiple holes in its side which are used to drain the bile in two directions, outwards into a bag and inwards into the intestine. The bag will be attached to the skin and left in place for a few days until the biliary tract has decompressed. During the period when the bag is attached, the catheter is flushed 2-3 times a day with sodium chloride to keep the side-holes open.
Why perform it?
If you are unsuitable for endoscopic procedures, PTCD is a possible alternative for you. It can be used to decompress the biliary ducts if they are blocked by a mass lesion or a stone, or to bridge a hole if you experience bile leakage.
What are the risks?
One of the most common complications is bleeding into the biliary tract, usually from a vein. This normally does not need treatment as it heals by itself. A less frequent complication is major bleeding requiring a blood infusion or further interventions, such as surgery or embolisation of the vessels.
If you have a biliary infection, the PTCD procedure may cause fever, chills and septicaemia. A further risk is the possibility that the areas around the tract will be punctured during the procedure, such as the gallbladder or bowel.
What is an image-guided biopsy?
An image-guided biopsy aims to provide diagnostic information by obtaining a sample of tissue from under the skin using imaging to navigate. The interventional radiologist will perform this procedure using special cutting needles which are available in a variety of diameters and lengths. The tissue sampled will usually be examined under a microscope by a pathologist and can also be analysed chemically.
How does the procedure work?
If you are on any medication that prevents blood clotting, you will stop taking it before the procedure, if possible.
You should not eat anything for at least four hours before the procedure starts. You may be asked to fast for longer, depending on the puncture and the complexity of your particular case. Before the procedure, the interventional radiologist will usually place a needle in your vein to make access easier during the procedure.
The interventional radiologist may use one of a number of image-guidance techniques to plan and monitor the placement of the needle during the aspiration procedure, including ultrasound, CT, MRI and fluoroscopy. This depends on the location and nature of the lesion.
Most biopsy procedures are performed under local anaesthesia or conscious sedation, so you will be awake but feel no pain. You may be asked to take antibiotics beforehand to reduce the risk of infection, but this is uncommon. You will lie down for the procedure – the exact position you will be asked to lie in depends on the access route that the interventional radiologist will use to safely approach the lesion.
The procedure will be carried out in a sterile and safe environment. The interventional radiologist will choose which type of needle to use according to the organ and tissue type which needs to be sampled, such as bone, soft tissue, lung, etc. The interventional radiologist will insert the needle and will guide it using imaging until the needle tip can be seen inside the lesion.
An image-guided biopsy can be performed as an in-patient or out-patient procedure. The site of the puncture and your vital signs will be monitored for 4-6 hours following the procedure. You will experience some mild discomfort around the puncture site during this time. If you undergo a lung biopsy, you will be given a chest X-ray 6-8 hours after the procedure to ensure that no air has been trapped in the cavity between your chest wall and your lungs. In most cases, you will be allowed to drink water a few hours after the biopsy procedure.
Why perform it?
If you have a lesion and your doctor needs further information to make a diagnosis, you may be referred for an image-guided biopsy.
There are a number of factors which may make the procedure unsuitable for you, including if you have a blood clotting disorder, if there is no safe route for the interventional radiologist to access the lesion, or if you have already been diagnosed using other procedures, such as diagnostic imaging.
The success rate of the biopsy procedure can vary depending on the location of the lesion and the type of needle used. Image guidance is used to confirm that the needle is placed correctly inside the lesion and to help avoid complications.
What are the risks?
If the interventional radiologist uses a small bone needle, the complication rate is low. The most common complications are bruising and infection. If you have had a lung biopsy there is a risk of pneumothorax, which means that air fills the gap between the lungs and the chest wall.
What is bone augmentation?
Bone augmentation techniques aim to stabilise a weakened or a fractured bone. These minimally invasive techniques include injection of bone cement designed for this purpose, the insertion of metallic rods or screws, or a combination of both techniques, depending on the location and on the type of fracture.
How does the procedure work?
The interventional radiologist will use image guidance to precisely insert the devices used to reinforce a weakened or fractured bone.
Why perform it?
Percutaneous image-guided bone fixation is performed to stabilise a weakened bone. The procedure is a minimally invasive alternative to conventional surgery and it may be recommended to treat a range of conditions, including bone metastases, osteoporotic fractures or fractures caused by trauma.
What are the risks?
Placing needles inside bone carries the risk of bleeding and infection. In rare cases, the surrounding structures such as nerves or vessels are damaged. Occasionally, optimal stabilisation cannot be achieved, which can cause a delayed fracture to another bone. You are especially at risk for this if you have advanced bone cancer.
Bibliography
What is brachytherapy?
Brachytherapy is a form of therapy used to treat cancer by placing radiation inside the body.
How does the procedure work?
The interventional radiologist will place small metal beads or wires into the cancerous tissue, usually using radiological imaging as a guide. These emit high energy radiation, which then spreads a short distance from this source into the surrounding tissue containing the tumour, whilst limiting radiation to the non-cancerous, normal tissues that are further away. The radiation kills the tumour cells.
Why perform it?
The procedure is performed to cure cancer or to limit its progression. It may be used alone or conjunction with other therapies including chemotherapy and surgery. It has been applied to a range of cancers including, but not limited to, prostate, cervix, liver, rectum and breast cancer.
What are the risks?
Placing the radiation source carries the risk of bleeding and infection. There is a risk of the radiation killing normal, non-cancerous cells. You may experience pain in the area treated.
What is tracheobronchial stenting?
Your airway system consists of the trachea, which is then divided into different sections, called the main stem and segmental bronchi, which supply both your lungs. Diseases which block the airways are very dangerous, as they may cause the lungs to collapse and prevent the patient from inhaling enough air, causing death.
A stent is a metal mesh tube that is inserted over a guidewire and placed in a vessel in order to keep it clear. Tracheobronchial stenting refers to the placing of a stent in a patient’s airways to treat or prevent restricted airflow. The procedure is minimally invasive and is most often used to relieve symptoms caused by cancerous tumours blocking airways.
Why perform it?
If you have a cancerous growth in your trachea or bronchi which cannot be operated on and is affecting your breathing, having a stent placed may relieve your breathlessness while you undergo chemotherapy and/or radiotherapy.
In some cases, a stent is placed to treat fistulas (holes) that have developed in the airway system or to treat blockages in the airway that are not cancerous. If the patient is a child, the use of biodegradable stents, which are absorbed over time, is recommended.
How does the procedure work?
You will have a general anaesthetic for the procedure, which will be carried out in an operating theatre by a team of interventional radiologists and surgeons. The doctors will use fluoroscopy and a bronchoscope (a tiny camera inserted into your body on a tube) for guidance.
An interventional radiologist will thread a guidewire into your airway system so that the stent can be guided to the correct location. Once placed in the affected area, the stent will expand, clearing the airway.
An oncologist may take a tissue sample before the stent is placed, if this would be beneficial in planning your optimal treatment.
In most cases, patients stay in hospital overnight, and you will be discharged from hospital once you have had a consultation with the thoracic and oncology teams who will provide your follow-up care.
What are the risks?
The majority of cases (over 95%) are successful, and most patients (70-80%) see significant clinical improvement 24-48 hours after the procedure. In 10-20% of cases, the stent migrates, meaning it moves to another part of the body. If this occurs, the stent will be removed and replaced with a new stent.
Other possible complications include bleeding, chest infection, temporary chest pain and the risk of the airways reacting to the stents, which can cause spasm and breathlessness.
What is carotid artery stenting?
The carotid arteries are the two large arteries on each side of your neck that supply your brain, neck and face with oxygenated blood. Sometimes plaque builds up in the arteries, which results in a condition called carotid artery stenosis (also known as carotid artery disease). Stenosis means that the space inside the artery has narrowed, restricting blood flow.
Carotid artery stenting (CAS, also referred to as carotid artery angioplasty with stenting) is a minimally invasive treatment option for effectively managing carotid artery stenosis and preventing stroke. It is a non-surgical treatment in which catheters (thin hollow tubes) are used to place a stent (a metal mesh tube) in the affected artery to ensure the passage stays clear, thus restoring blood flow.
While some patients with carotid artery stenosis have no symptoms, the condition can lead to the formation of blood clots (thrombosis), mini-strokes (which are similar to strokes but only last a few minutes) and strokes (where the artery supplying blood to the brain is blocked). The CAS procedure is a possible alternative for patients for whom the traditional surgical option, carotid endarterectomy (CEA), may not be suitable.
How does the procedure work?
You will be given a local anaesthetic for the procedure. Using fluoroscopy to monitor and guide the process, the interventional radiologist will puncture an artery in your groin or arm with a needle, and will insert a balloon-tipped catheter into the carotid artery, guiding the catheter into the narrowed area. The balloon will then be inflated and deflated, compressing the fatty plaque or blockage against the artery walls, widening the blood vessel and increasing blood flow. After this, the balloon will be removed.
The interventional radiologist will use another catheter to place a stent, and, in some cases, will further expand the stent using another balloon-tipped catheter. The stent remains in place so that there is a clear passage in your artery.
Why perform it?
CAS may be an appropriate treatment for you if you have symptoms of carotid artery disease and are at increased risk of suffering complications from surgery. It may be beneficial if you have undergone traditional surgery but your arteries have become re-narrowed (called restenosis), if the location of the narrowing in the artery means it cannot be operated on or if narrowing has occurred following radiation treatment. It may also be considered as a treatment for you if you have no symptoms of carotid artery disease but are awaiting surgery for carotid stenosis.
What are the risks?
The most severe risks of CAS are stroke and death. Stroke can occur during the procedure and is usually caused by fragments dislodging from the plaque into the circulation of blood in the brain.
The minimally invasive treatment of CAS and the surgical treatment CEA have been shown to have similar short-term and long-term outcomes, though CAS is associated with a higher risk of stroke or death during the procedure if the patient is elderly. However, CAS has a lower risk of heart attack, cranial nerve palsy and bruising at the access site than CEA.
In some cases, patients experience a temporarily decreased heart rate or cardiac arrest when the carotid artery is widened at its main branch point, though these complications can be avoided when patients are given atropine.
Other possible complications of carotid artery stenting include spasm, the formation of blood clots, tearing in the artery wall and hyperperfusion syndrome, which can lead to problems with the nervous system.
You may also experience complications at the access site, including bleeding, bruising, blood clots, injury to the artery causing blood to leak and pool outside the arterial wall (called a pseudoaneurysm) and bleeding in the muscle and tissues behind the abdominal wall cavity. Many of these complications can be treated without surgery. You may have low blood pressure 2-24 hours after the procedure, but this does not cause any clinical problems.
Although it is uncommon, it is possible to have an allergic reaction to the dye used to enhance imaging.
What are vascular closure devices?
Once a minimally invasive procedure has been performed, the interventional radiologist will remove the devices used during the procedure, such as catheters or sheaths. At this point, patients usually experience some minor bleeding at the access point for the procedure. Physicians tend to stop this bleeding using a technique called manual compression, in which they manually apply pressure to the site for 15-20 minutes. The patient then has to stay immobile for 4-6 hours.
Although this method generally works well, it is time-consuming and often uncomfortable for the patient. Further, this technique is not effective in some patients.
Vascular closure devices provide an alternative to manual compression. First introduced in the early 1990s, they are specially designed to stop bleeding more quickly, which is both more comfortable for patients and allows them to start moving around sooner.
How do closure devices work?
Vascular closure devices are inserted at the end of a procedure. The devices available fall into two categories, passive closure devices and active closure devices. Passive vascular closure devices stop the bleeding with the use of material that leads to the formation of blood clots or by way of mechanical compression. However, these do not stop bleeding particularly rapidly and patients must remain immobile for the same amount of time as with manual compression.
Active vascular closure devices use a variety of methods to directly close the entry site in the artery. For example, such devices include collagen-based and suture-based products or clips. These effectively close the access site, but often require part of the device to remain in the artery, which can cause complications.
Newer devices use materials, such as polyethylene glycol, that dissolve after a short period of time. These are applied to the outside of the artery only and so are considered a more gentle option.
Why use them?
Using vascular closure devices causes less pain and discomfort to patients compared to manual compression. These devices also stop bleeding more quickly, meaning that, following a procedure, patients can move about and leave the hospital sooner than if other techniques had been used.
The devices can be especially beneficial for older and less healthy patients, who may be unable to lie flat on their backs for several hours. They are also a welcome alternative for patients for whom manual compression is generally not effective, such as those who suffer from blood clotting disorders or who are obese. Similarly, they are useful for patients who undergo procedures that require large arterial access (such as endovascular aortic aneurysm repair). For these patients, manual compression can be difficult and usually does not work well, so vascular closure devices provide a better option.
What are the risks?
Complications can occur, but these are rare. The most common complication is that the device fails (which occurs in less than 6% of cases). When this happens, the physician must immediately resort to manual compression. Sometimes the bleeding occurs after some delay, but this also involves applying simple manual compression to the site. Most of the devices entail a small risk of a blockage in the target artery. The risk of infection is very low (less than 1%).
What is provocative discography?
Provocative discography is an image-guided procedure in which a radiological contrast agent is injected into the intervertebral disc (which is between two vertebrae). The contrast agent makes the area visible under imaging and so provides both anatomical and functional information about the disc.
How does the procedure work?
If the procedure is performed between two vertebrae, the interventional radiologist will insert a thin needle into the intervertebral disc under image guidance. If the procedure is performed on a disc in your neck, the entry point will be at the front or side of your neck, whereas if the disc being treated is lower down, the entry point will be in your back.
Once the interventional radiologist has completed the contrast injection, they will assess the shape of the disc on radiographs or a CT scanner. The contrast injection also increases the pressure between the discs, meaning that the functional evaluation in the discography procedure consists of pain induced by the interventional radiologist and the assessment of your response.
Why perform it?
You may be suitable for a provocative discography if you are suffering from persistent neck or back pain which has not responded to conservative treatment and if non-invasive tests such as MRI have not provided sufficient information about your condition.
You should only undergo a discography if you are being considered for surgery, as the anatomical and functional results of the procedure influence the surgical decision-making process.
What are the risks?
The reported rate of complications following the procedure is less than 1%. The most serious complication is infection. When puncturing an intervertebral disc, needle contact with a nerve may occur but this generally causes only temporary symptoms.
What is image-guided percutaneous drainage?
Image-guided percutaneous drainage involves using a catheter (a thin tube) to drain an abscess or a collection of fluid or air under image guidance. The interventional radiologist will insert a flexible catheter through a small cut in your skin and will guide the catheter to the collection of fluid or air. The fluid or air will then be collected in a drainage bag.
Drainage catheters are available in a variety of sizes, shapes and types. The interventional radiologist will choose the catheter according to the type of fluid, along with other factors.
How does the procedure work?
If you are on any medication that prevents blood clotting, you will stop taking it before the procedure, if possible.
You should not eat anything for at least four hours before the procedure starts. You may be asked to fast for longer, depending on the puncture and difficulty of your particular case. Before the procedure, the interventional radiologist will usually place a needle in your vein to make access easier during the procedure.
Why perform it?
Percutaneous drainage is recommended to treat fluid or air collections which produce symptoms (such as pneumothorax, which is the collection of air or gas in the gap between the chest wall and the lungs). It can also treat recurrent fluid collections by using medication and is a minimally invasive method of draining abscesses.
This procedure may not be suitable for you if you suffer from a blood clotting disorder or if the interventional radiologist cannot find a safe access route for the catheter.
The percutaneous drainage procedure cures infected fluid/air collections in over 80% of patients, though failure occurs in 5-10% of patients.
Because of the wide range of types of uninfected collections, the success rate of drainage for uninfected collections is highly variable.
What are the risks?
There are some risks associated with the procedure. Major complications include bacteraemia (the presence of bacteria in the blood, which occurs in 2-5% of cases) and septic shock (caused by severe infection and sepsis, which occurs in 1-2% of cases). Other complications include the risk of haemorrhage and superinfection (infection of a sterile collection of fluid, following a previous infection).
What is the embolisation procedure for bleeding?
Embolisation is a minimally invasive treatment which uses materials to block the affected vessel and so stop bleeding. There are a number of possible causes of bleeding severe enough to require this treatment, including trauma, blood clotting disorders, infections, anatomical defects and tumours.
How does the procedure work?
The procedure aims to stop blood flowing to the source of the bleeding whilst also preserving the blood flow to the surrounding area.
The interventional radiologist will usually insert a 2-3 mm tube into your groin and will guide this to the affected blood vessel. They will then insert small resin particles (microparticles), glue or small metal spirals (coils) into the bleeding vessel or vessels. This causes the vessel or vessels to become blocked and so stops the bleeding.
Why perform it?
The main reason for treating bleeding is that if too much blood is lost, the patient may go into life-threatening shock.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the possibility that microparticles, glue or the coils may move to other areas of the body and block other artery branches.
What is haemoptysis embolisation?
Haemoptysis is the medical term for coughing up blood or bloody mucus from your lungs or airway. Massive haemoptysis is defined as 200-600 ml of blood coughed up within a period of 24 hours or less. The causes of haemoptysis include blunt trauma, infections, tumours and defects in your lung.
Haemoptysis embolisation is a minimally invasive procedure which deliberately blocks the bleeding vessel, such as the bronchial arteries or pulmonary veins.
How does the procedure work?
The aim of the procedure is to stop the blood flowing into the veins which are causing the haemoptysis whilst also preserving blood flow to the surrounding area.
The interventional radiologist will insert a 2-3 mm tube into your groin and will guide it under imaging to the affected blood vessel. Small resin particles (microparticles) or small metal spirals (coils) will be inserted into the bleeding vessel or vessels. This causes the vessel or vessels to become blocked and so stops the bleeding.
Why perform it?
There are two main reasons why it is important to treat haemoptysis. If too much blood is lost, the patient may go into shock, which is life-threatening. There is also the risk of the patient inhaling the blood: if the patient breathes in too much blood, they may drown.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the possibility that microparticles or the coils may move to other areas of the body and block other artery branches.
What is epistaxis embolisation?
Epistaxis is the medical term for a nosebleed, which is relatively common and refers to bleeding from the nose. A nosebleed may be caused by a number of things, including blunt trauma, infections, tumours and the structure of your nose.
Epistaxis embolisation is a minimally invasive procedure in which the blood vessel is deliberately blocked in order to stop the nosebleed.
How does the procedure work?
The aim of the procedure is to stop the blood flowing into the vessels which cause the nosebleed, without preventing blood from flowing into the area around the affected vessel.
The interventional radiologist will insert a 2-3 mm tube into your groin and then guide the tube under imaging to the blood vessel causing the nosebleed. They will then insert small resin particles (known as microparticles) or small metal spirals (coils) into the bleeding vessel or vessels. This causes the vessel or vessels to become blocked and so stops the bleeding.
Why perform it?
The main reason to treat nosebleeds is the risk of breathing in blood, as if too much blood is inhaled there is a risk of drowning.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the risk of the microparticles or the coils moving to other areas of your body or blocking other artery branches.
What is embolisation for pelvic congestion syndrome?
Pelvic congestion syndrome is caused by varicose veins inside the patient’s lower abdomen and causes chronic pain, which may become worse when standing. A minimally invasive treatment for pelvic congestion syndrome is embolisation, which reduces blood flow to the enlarged veins by blocking vessels supplying these veins.
How does the procedure work?
The procedure reduces blood flow to the varicose veins, which relieves the symptoms of pelvic congestion syndrome.
The interventional radiologist will insert a 2-3 mm catheter (tube) into a blood vessel in your groin and will guide the catheter to the affected blood vessel using image guidance. The interventional radiologist will usually use glue or coils (small metal spirals) to block the veins supplying the enlarged veins, though sometimes they will use an injection of alcohol (sclerotherapy). This causes blood to be diverted away from the affected veins and so reduces the symptoms of pelvic congestion syndrome.
Why perform it?
It is advised that you undergo treatment for pelvic congestion syndrome if you are experiencing symptoms which cause you discomfort, such as pain in your lower abdomen or a feeling of heaviness in your bladder area.
What are the risks?
Minor risks include bruising in the groin. More significant risks include glue or coils moving to other areas of your body and blocking other vessels.
What is embolisation for post-partum haemorrhage?
Unfortunately, it is not uncommon for patients who have given birth to haemorrhage, meaning they lose a lot of blood after the baby is delivered. This is known as post-partum haemorrhage, and can be life-threatening. Embolisation is a minimally invasive treatment which seals off the bleeding vessels.
How does the procedure work?
The interventional radiologist will insert a 2-3 mm catheter (tube) into a blood vessel in your groin and will guide it under imaging to the right and left uterine arteries. They will then inject microparticles (particles which are smaller than a grain of sand) into the uterine arteries, reducing blood flow to the uterus and so controlling acute bleeding.
Why perform it?
Without treatment, a patient suffering from post-partum haemorrhage may go into shock, which is life-threatening. The embolisation procedure is successful in controlling the bleeding and stabilising the patient in over 95% of cases.
What are the risks?
Minor risks include bruising in the groin. More significant risks include microparticles or coils moving to other areas of your body and blocking other arteries.
What is post-traumatic bleeding embolisation?
Post-traumatic bleeding embolisation is performed to stop bleeding caused by traumatic injuries. The procedure uses materials to block the affected vessel and so stops the bleeding. Accidents can result in massive organ damage with subsequent life-threatening bleeding. If a patient is bleeding severely and this cannot be controlled by first-line treatment options, this minimally invasive procedure may stop the bleeding quickly and without the need to perform open surgery.
How does the procedure work?
The procedure aims to stop blood flowing into the haemorrhaging vessels whilst preserving blood flow to the surrounding vessels and organs.
The interventional radiologist will insert a 2-3 mm tube into a blood vessel in your groin and will guide the tube under image guidance to the bleeding vessel or vessels. They will then insert small resin particles (microparticles), glue or small metal spirals (coils) into the bleeding vessel or vessels. This causes the vessel or vessels to become blocked and so stops the bleeding.
Why perform it?
There are two main reasons why it is important to treat post-traumatic bleeding. If too much blood is lost, the patient may go into shock, which is life-threatening. It is also possible for large bruises to form, which could compress other organs or muscles.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the possibility that microparticles, glue or the coils may move to other areas of the body and block other artery branches.
What is uterine fibroid embolisation?
Uterine fibroids cause a number of unpleasant symptoms, including pelvic pain and bleeding. Uterine fibroid embolisation is a minimally invasive procedure which aims to relieve the symptoms by preventing blood flow to the fibroids.
How should I prepare for UFE?
After your interventional radiologist has determined that your fibroids should best be treated with embolisation, he will let you know how to prepare for the intervention. You will usually be admitted to your hospital ward the day before your procedure. You may be given some sedation during the procedure. You will be asked to remove your clothes and put on a hospital theatre gown. If you have previously reacted to intravenous contrast X-ray dye (the dye used for kidney X-ray and CT scanning) or have any other allergies please let your interventional radiologist know before you are admitted. Blood tests will be performed while you are on the ward; these will include hormone levels and haemoglobin checks, the latter to check if you are anaemic.
Usually the embolisation is carried out under local anaesthesia during a short stay in hospital.
How does the procedure work?
The aim of the procedure is to stop blood flowing into the vessels which supply the fibroids whilst preserving blood flow to the surrounding area.
The interventional radiologist makes a small nick in the skin (less than one quarter of an inch) in the groin to access the femoral artery, and inserts a catheter (a tiny tube, like a piece of spaghetti) into the artery. Local anaesthesia is used so the needle puncture is not painful. The catheter is threaded through the artery to the uterus while the interventional radiologist guides the procedure with the help of a moving X-ray (fluoroscopy). X-ray “dye” is injected into the catheter to visualize the blood supply to the fibroids. You will feel a momentary hot flush in your pelvis. It will “tweak” your bladder and make you feel as if you have wet yourself, this will last a few seconds. As the uterine artery is accessed you may feel further tiny hot flushes as the radiologist injects a small amount of the “dye” to visualize the vessel.
After identifying abnormal arteries supplying blood to the fibroids, the interventional radiologist injects tiny plastic particles the size of grains of sand into the artery. This cuts off the blood flow and causes the tumour (or tumours) to shrink. The artery on the other side of the uterus is then treated. The skin puncture where the catheter was inserted is cleaned and covered with a bandage.
How long will it take?
Every patient’s situation is different, and it is not always easy to predict how complex or how straightforward the embolisation will be. Some uterine fibroid embolisations do not take very long, perhaps an hour. Other embolisations may be more involved and take longer, perhaps two hours. Expect to be in the radiology department for two hours.
What will happen afterwards?
Fibroid embolisation usually requires a short hospital stay. Pain-killing medication and medication that controls swelling are typically prescribed following the procedure to treat cramping and pain. Fever sometimes occurs after embolisation and is usually treated with paracetamol (acetaminophen). Many women resume light activity after a few days and the majority of women are able to return to normal activity within one or two weeks.
You will have to see your IR for a check-up one month and six months after the procedure. A control MRI will probably be prescribed after three or six months.
Why perform it?
Uterine fibroid embolisation is performed to reduce the symptoms caused by fibroids whilst avoiding surgical methods. Patient selection should always be performed by a gynaecologist, so if you are interested in seeing if you would be suitable for this procedure, you are advised to discuss this with your gynaecologist.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the possibility that the glue or coils may move to other areas of the body and block other artery branches.
What is varicocele embolisation?
Varicocele embolisation is a minimally invasive procedure which is used to treat abnormal enlargement of the veins which drain the testicles, which are known as varicoceles. The procedure works by blocking the blood flow to the enlarged vein, which reduces pressure on the varicoceles.
How does the procedure work?
The interventional radiologist will usually insert a 2-3 mm catheter (tube) into a blood vessel in your groin and will then guide the catheter under image guidance to the affected blood vessel. This will be followed by the interventional radiologist delivering glue or coils (small metal spirals) to the enlarged vessels, although in some cases a direct injection of alcohol can be used, known as sclerotherapy. This will relieve your symptoms by blocking the blood vessel and reducing blood flow.
Why perform it?
If you have a varicocele, it is recommended that you seek treatment when you experience clinical symptoms such as pain in your scrotum, a feeling of heaviness in your testicle, you can see or feel the enlarged veins within your scrotum, or you experience infertility as a consequence of the varicocele.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the possibility that the glue or coils may move to other areas of the body and block other artery branches.
What is embolisation for vascular malformations?
The embolisation procedure for treating vascular malformations is a minimally invasive method which aims to block blood vessel abnormalities which are causing the patient discomfort. The procedure is performed using specially designed materials, known as embolic agents.
How does the procedure work?
The interventional radiologist will insert a 2-3 mm catheter (tube) into a blood vessel in your groin and will then move the catheter under image guidance to the arteries which lead to the vascular malformation. When the particular vessel which is supplying the blood to the vascular malformation is found, the interventional radiologist will insert a smaller catheter. They will then insert glue or small metal spirals (coils) into this vessel, which causes the vessel or vessels to become blocked.
Why perform it?
There are many reasons why a vascular malformation embolisation may be beneficial for you. If you experience pain, recurrent bleeding or have aesthetic or functional problems as a result of the vascular malformation, it is important that the vascular malformation be treated.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the possibility that the glue or coils may move to other areas of the body and block other artery branches.
What is embolisation in oncology?
Tumours need a consistent supply of blood in order to grow. Embolisation is a minimally invasive procedure performed by interventional radiologists, in which the blood supply to masses or vessels which are causing symptoms in a patient is cut off, relieving the symptoms the patient experiences. In oncology, this involves using liquid, particles or microspheres to block blood vessels, redirecting blood flow away from the tumour. This causes the tumour to shrink and die.
Why perform it?
If you have large tumours in your liver, kidneys, lungs or bones, this treatment may be beneficial for you. There are different ways in which embolisation can be used in oncology. It can be used simply to cut off blood supply to the tumour (bland embolisation), or combined with chemotherapy to deliver the drugs directly into the tumour (chemoembolisation), or the particles may contain doses of radiation to selectively kill the tumour cells (radioembolisation).
Embolisation is also suitable for some non-cancerous tumours. Occasionally, embolisation may be used to reduce blood supply before a surgical procedure to increase patient safety.
How does the procedure work?
You should not eat anything before the procedure, and you may be given a sedative to help you relax. It is important that you stay still during the procedure to ensure that the X-ray images taken are accurate. The procedure will last around one hour.
You will be given a local anaesthetic for the procedure. The interventional radiologist will puncture an artery in your thigh with a small needle and will then thread a combination of plastic tubes (called sheaths and catheters) and guidewires into your arteries.
The interventional radiologist will inject a contrast medium (dye) through a catheter so that the area can be seen clearly under imaging. Then, the interventional radiologist will carefully navigate a microcatheter as close as possible to the tumour and will release the embolic particles. The particles are usually microspheres that are less than 0.5 mm in size and these may be combined or loaded with chemotherapy or yttrium radiation.
Most patients experience some pain and nausea after the procedure, so you will be offered strong painkillers and medication to prevent nausea. You may be discharged on the same day, but if you experience severe symptoms after the procedure you may need to stay in hospital overnight.
What are the risks?
The technical success rate, defined as successful delivery of the particles into the tumour, is usually over 95%. Clinical success (defined as a partial or complete death of the tumour and shrinkage of the tumour) and is around 30-50%, though it varies depending on the location, extent and biology of the underlying disease.
You may be offered multiple treatments to optimise the response, and 10-20% of the cases may also require more drastic treatment (surgery or ablation) in the future.
The main risk is non-target embolisation, meaning that the particles are accidentally released to normal vessels, which may destroy healthy tissue or restrict blood supply to an organ. Less severe side effects include bleeding, bruising and infection at the puncture site. In rare cases, the patient experiences abdominal haemorrhage, meaning they must stay in hospital and may need blood transfusions.
It is possible to have an allergic reaction to the contrast medium or for the iodine in the dye to affect the kidney. There is also a risk of post-embolisation syndrome, which causes fever, nausea and pain.
What is embolisation of the bronchial arteries?
Bronchial artery embolisation is a treatment for haemoptysis, which is the coughing up of blood or bloody mucus from the lungs or airway. Haemoptysis may be caused by blunt trauma, infections, anatomical defects or tumours.
Bronchial artery embolisation is a minimally invasive procedure which reduces blood flow to the affected veins in the respiratory system and so stops the bleeding.
How does the procedure work?
The aim of the procedure is to stop blood flowing to the vessels which are bleeding in the lung whilst preserving blood flow to the surrounding area. The vessels supplying the lungs with blood are called the bronchial arteries.
The interventional radiologist will insert a 2-3 mm catheter (tube) into a blood vessel in your groin and will guide the catheter under image guidance to the affected blood vessel. They will then insert microparticles (resin particles smaller than a grain of sand) or coils (small metal spirals) into the bleeding vessel or vessels. This prevents blood from entering the vessels and so stops the bleeding.
Why perform it?
If the patient loses a lot of blood as a result of haemoptysis, they may go into shock, which is life-threatening. It is also possible for the patient to drown if the blood goes into their airways.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the risk of the microparticles or coils moving to other areas of your body and blocking other artery branches.
What is embolisation of the bronchial arteries?
Bronchial artery embolisation is a treatment for haemoptysis, which is the coughing up of blood or bloody mucus from the lungs or airway. Haemoptysis may be caused by blunt trauma, infections, anatomical defects or tumours.
Bronchial artery embolisation is a minimally invasive procedure which reduces blood flow to the affected veins in the respiratory system and so stops the bleeding.
How does the procedure work?
The aim of the procedure is to stop blood flowing to the vessels which are bleeding in the lung whilst preserving blood flow to the surrounding area. The vessels supplying the lungs with blood are called the bronchial arteries.
The interventional radiologist will insert a 2-3 mm catheter (tube) into a blood vessel in your groin and will guide the catheter under image guidance to the affected blood vessel. They will then insert microparticles (resin particles smaller than a grain of sand) or coils (small metal spirals) into the bleeding vessel or vessels. This prevents blood from entering the vessels and so stops the bleeding.
Why perform it?
If the patient loses a lot of blood as a result of haemoptysis, they may go into shock, which is life-threatening. It is also possible for the patient to drown if the blood goes into their airways.
What are the risks?
Minor risks include bruising in the groin. More significant risks include the risk of the microparticles or coils moving to other areas of your body and blocking other artery branches.
What is the endovascular treatment of abdominal aortic aneurysms (EVAR)?
The aorta is the largest vessel in your body and carries the blood from your heart to the rest of your organs. An aneurysm occurs if the arterial wall weakens and develops a bulge, meaning blood is flowing to the weakened area. Abdominal aortic aneurysms (AAA) are also known as ‘the silent killer’ because once they grow and rupture, there is an 80-90% risk of immediate death.
EVAR is a minimally invasive procedure in which an interventional radiologist places a covered stent (a metal mesh tube covered with fabric) into the area with the aneurysm so that blood can flow through the vessel. The stent is inserted through an artery in the patient’s groin, using X-rays to guide the stent to the aneurysm.
Why perform it?
If you have a small AAA that has a diameter of less than 5 cm, it is unlikely to rupture, so it is recommended that the aneurysm is regularly monitored by a vascular expert. If, however, you have an aneurysm that is smaller than 5 cm but it is growing by more than 1 cm every year or it is causing symptoms such as back pain and tenderness, EVAR may be beneficial for you.
If your aneurysm is larger than 5 cm, you will need treatment to prevent the aneurysm from rupturing. EVAR is a possible treatment option.
How does it work?
You will be given a combination of an epidural and a local anaesthetic for the procedure. The interventional radiologist will make a small cut at the top of each leg so that they can insert a short tube (known as a sheath), which allows the vessels in your groin to be accessed safely. Using fluoroscopy for guidance, the interventional radiologist will insert guidewires and catheters (thin flexible tubes). A contrast medium (dye) will be injected into the area being treated so the exact location of the aneurysm can be seen under imaging. The interventional radiologist will then use the guidewire to move a stent to the aneurysm.
When the stent is placed in the correct location, it will expand, sealing the aneurysm and restoring normal blood flow through the vessel.
After the procedure, your vital signs will be monitored and you will stay in hospital for 2-3 days. You may experience bruising and pain, though this can be treated with standard painkillers. Moving around once you are able to do so is encouraged. You will need to have the stent regularly checked using CT or ultrasound to ensure that it is in good condition and to avoid long-term problems.
What are the risks?
EVAR is recommended as a preventative treatment to avoid aneurysm rupture and death. The majority of patients suffer no immediate major problems and rupture of the aneurysm is avoided in over 99% of patients. There are lower rates of pain and serious complications than with surgery, but the main limitations of EVAR are that the stent may move to another area of the body and that blood may start collecting in the aneurysm again. This means that you will require regular monitoring, so that if any problems do occur they can be resolved as soon as possible.
Minor complications include the risk of bruising and infection. There are some serious complications associated with the procedure, including death, stroke, tissue death, limb loss and injury to the kidneys. The rate of serious complications is estimated to be less than 15%, and the risk of death during the procedure is less than 1.5%, which is nearly three times lower than the risk of dying during open surgery (around 4.5%). Some patients react to the iodine in the dye used for imaging, which can affect the kidneys.
What is an aortic dissection?
The aorta is the largest artery in your body. An aortic dissection is when the layers of the aortic wall are separated by a tear in the inner wall. The aortic wall splits into two lumens (channels): a true lumen, meaning the original lumen; and a false lumen, which is in the aortic wall. If there is high blood pressure in the false lumen, the true lumen is compressed. This decreases blood supply to the organs, leading to organ failure and restricted blood supply to the lower limbs.
You may also experience a rapid widening of the part of the aorta near your heart, which can lead to it rupturing.
How does the procedure work?
The placement of a stent graft is usually performed under general anaesthesia. The interventional radiologist will use surgery to access an artery at the top of your leg for the procedure. They will also insert an angiography catheter through an artery in your right arm for injections of contrast material before and after the placing of the stent graft. The interventional radiologist will place a guidewire into your aortic arch and will then pass the stent graft over the wire and use this to cover the tear on the inner wall of the aorta. This protects the true lumen from the expansion of the false lumen.
If your case is critical, you may need to undergo additional stenting of these vessels to avoid restricting the blood supply.
If a stent graft is not enough to decompress the false lumen, you may be advised to have a procedure called fenestration of the intimal flap. This means that a hole will be made in the membrane between the true and false lumens to equalise the pressure between them. The interventional radiologist will create a connection between the lumens using a needle and positioning a wire through the puncture site. They will then widen the hole using a tiny balloon and may implant a stent to keep the connection open.
Why perform it?
The purpose of these procedures is to restore the true lumen as well as the blood supply to your organs and lower limbs. The procedures also stabilise the pressure and blood flow in the area and protect the aorta from widening.
What are the risks?
Depending on the location of the aortic tear, it may be necessary for the interventional radiologist to place the stent graft over the origin of an artery in your chest, which would result in a decreased blood supply to your left arm. This may lead to weakness of the arm, dizziness and ischaemic injuries to your brain. If you experience these symptoms, the artery will be treated to improve blood flow.
In some cases, it is not possible to separate the false lumen, which would make it necessary for you to undergo further treatment. Other risks include the misplacement of the stent graft and the rupture of the vein used for access, but these are rare.
What is the endovascular treatment of arteriovenous malformations?
Arteriovenous malformation (AVM) refers to an abnormal connection between arteries and veins. Different types of AVMs occur in different clinical situations, including infantile haemangioma (a benign tumour made up of blood cells), and connections present at birth which are between vessels larger than capillaries (such as veins or arteries) – these are known as high-flow AVM.
The most common form of AVM is low-flow AVM, in which the abnormal connections are in an area with a low blood flow, meaning the space fills and empties slowly. This may be due to compression or gravity, a condition such as Klippel-Trénaunay syndrome or may be a combination of both these types. Another form of AVM is lymphatic malformations, though these are uncommon and may include cystic lesions (cysts, abscesses or bruising).
Klippel-Trénaunay Syndrome (KTS) is a rare congenital medical condition in which blood vessels and/or lymph vessels fail to form properly. The three main features are a port-wine stain, venous and lymphatic malformations, and soft-tissue enlargement of the affected limb. The condition tends to affect a single limb, usually a leg.
Although AVMs are congenital (present at birth), they are mostly diagnosed in adults under 40, and have a death rate of 10-15%.
In most cases, AVMs have no symptoms and so are discovered by chance, but the symptoms the patient experiences or does not experience depend on the location of the AVM. AVMs sometimes cause intense pain or bleeding and may lead to other serious medical problems. AVMs do not always require treatment.
You may be advised to undergo treatment for the AVM if you experience haemorrhaging, pain, ulceration, if your heart is pumping too much blood, if you have a mass which interferes with normal activity or growth, or if you develop disfiguring lesions.
The only indication that the treatment may not be suitable for you is if your anatomical situation would prevent it, meaning that the structure of the affected blood vessels may prevent treatment from being carried out. It is therefore vital that the interventional radiologist carries out imaging before the procedure to evaluate which type of AVM you have and how the feeding vessels are structured.
How does the procedure work?
The interventional radiologist will choose the type of endovascular procedure which is most suitable for you, depending on the site and type of your AVM. If the treatment is for infantile haemangioma, it may be removed surgically, to prevent psychological trauma, or it may be managed using embolisation.
If you are being treated for high-flow AVM, the therapy will aim to block the connection between the arteries and veins by embolising the tangle of blood vessels (nidus) or the central part of the lesion where the majority of the veins are present. The interventional radiologist will choose the material for the embolisation procedure based on the type of AVM you have and will aim to completely get rid of the nidus whilst also preserving normal blood flow. The materials used for the procedure are usually materials designed especially for the procedure, such as glue or metallic coils. Sometimes the nidus is directly punctured by injecting an embolic agent.
If you are undergoing treatment for low-flow AVM, you will be given an injection of sclerosing agent, a drug which is injected into vessels to make them shrink. In some cases, this will be done under fluoroscopy. There are limited treatment options for congenital venous dysplasia, but sometimes no treatment is needed. In severe cases, the interventional radiologist may use surgical stripping, sclerotherapy or an endovascular ablation technique. If you have symptoms on your skin, such as a port-wine stain, you may be advised to have laser treatment.
If you have a lymphatic malformation which contains fluid, a drainage treatment will be most suitable for you.
Why perform it?
Minimally invasive treatment can be performed for therapeutic reasons (to treat the condition) or for palliative reasons (to relieve the symptoms). The aim of the procedure is to exclude blood flow from the lesion and so reduce the symptoms and risks of AVM, such as bleeding.
The rate of bleeding varies from patient to patient, but if your AVM is associated with an aneurysm then the risk of bleeding is over 50%.
What are the risks?
Endovascular procedures to treat AVM also carry some risks, such as bleeding, bruising or ulcers at the site of the puncture, the embolic agent causing embolisation somewhere other than the target area, restricted blood supply if vessels supplying an area with blood are blocked, and toxicity, either locally or to other organs, caused by the blockage or sclerosing agent.
What is endovascular treatment of intracranial aneurysms?
An aneurysm is a weakness in the wall of a blood vessel which causes the blood vessel to swell. When an aneurysm develops inside the brain, it is called an intracranial aneurysm. Intracranial aneurysms are associated with a high risk of bleeding in and around the brain, which can have catastrophic consequences. Endovascular treatment of intracranial aneurysms is the non-surgical treatment of intracranial aneurysms using microcatheters (small and flexible plastic tubes) and X-ray guidance.
The procedure involves inserting tiny metal spirals (coils) into the blood vessel to act as a physical barrier and encourage blood clotting, preventing bleeding. A metal mesh tube (stent) may be used to keep the coils in place and support the walls of the blood vessel. Sometimes stents are used without coils to change the blood flow and encourage clotting in the aneurysm.
How does the procedure work?
You will be under general anaesthesia for the procedure. Using fluoroscopy for guidance, the interventional radiologist will insert a catheter through an artery in your groin or arm and will move it to the location of the aneurysm.
The interventional radiologist will then deposit tiny metal coils through the catheter and into the aneurysm, which stimulate blood clotting. Filling the aneurysm in this way stops blood flow to this area. A stent may be used to hold the coils in place and cover the aneurysm.
Why perform it?
A ruptured intracranial aneurysm that causes bleeding to the brain or to the surface of the brain should be treated urgently to stop the bleeding, minimise damage to the brain and prevent bleeding in the future. Unruptured aneurysms are sometimes treated to minimise any future risk.
What are the risks?
The procedure carries a risk of the aneurysm bursting, leading to bleeding in and around the brain. One or more of the coils may move out of place in the aneurysm or blood clots may develop during or after the procedure, either of which may block important blood vessels. You will probably be prescribed treatment to prevent blood clots developing for at least three months.
Andrea Avraamidi 55-57, Strovolos 2024, Nicosia,
Cyprus
Email: consulting at ncir.com.cy
Phone: +357 99 44 08 22