What is Interventional Radiology (IR)?

Interventional Radiology (IR) is sometimes referred to as Image Guided Surgery as we use imaging technology (such as x-ray, CT or ultrasound) to look inside patients and perform minimally invasive procedures. It is commonly confused with key-hole surgery but in fact the holes we make are even smaller than key-hole surgery and is therefore sometimes called pin-hole surgery as we operate through a hole the size of a large needle. The vast majority of procedures can be performed under local anaesthetic or sedation with only a very few complex cases requiring a general anaesthetic.

Interventional Radiologists first train as radiologists to learn how to use and interpret the imaging technology but then undertake further specialist training in minimally invasive image guided surgery to then integrate the two roles.

Interventional Radiology has existed for many years with the first procedure performed in 1964 by Charles Dotter who dilated the main blood vessel in the leg with a series of dilators in a patient with gangrene. The procedure allowed more blood to get to the foot and it healed without the need for surgery. We now use inflatable balloons to do this procedure and there are many other procedures which have been developed over the years which can help avoid major open surgery.

Interventional Radiology procedures usually involve guiding a needle into the body using ultrasound or CT and accessing a particular organ (liver, kidney, stomach etc) or a vessel (artery or vein), then guiding a wire and catheter through the needle into that area. Using a real-time x-ray camera, the wire and catheter can then be guided through the body to perform whatever procedure is required.

Interventional Radiology can be divided into 4 main subgroups:

1. Vascular Intervention (Arterial) – procedures involving the arteries throughout the body such as angioplasty (balloon dilatation of narrowed blood vessels) or embolisation (blocking off blood vessels to tumours or when someone is bleeding internally).

2. Vascular Intervention (Venous) – procedures involving the veins such as inserting lines into veins, inserting filters to prevent clot travelling around the body (IVC filters) or using devices to suck clot out of blocked veins (thrombectomy).

3. Non-vascular Intervention – procedures not involving the blood vessels such as unblocking kidneys (nephrostomy) or the liver (PTC), injecting cement into collapsed bones (vertebroplasty) or inserting feeding tubes into the stomach (RIG).

4. Interventional Oncology – procedures performed for the diagnosis or treatment of cancer such as tumour ablation (killing tumour cells by inserting a needle into a tumour and heating it up) or injecting chemotherapy coated beads into tumours to kill them (TACE).