What is IVR?
IVR · Interventional Radiology
An interventional radiology technique that uses imaging equipment to reach specific areas inside the body
Not an actual procedure.
What IVR is
IVR is a medical field in which doctors watch the inside of the body on CT, ultrasound, or X-ray fluoroscopy while guiding a thin tube (catheter) or needle to a target area to diagnose or treat it.
Instead of a large incision, the procedure often goes through an opening of a few millimetres. Besides cancer, it is used for bleeding, vascular disease, and pain management.
What “Interventional Radiology” means
IVR stands for Interventional Radiology. “Interventional” means stepping in to act, and “radiology” is the medical specialty of imaging.
In Japan the term 画像下治療 (image-guided treatment) is also used. The name reflects radiology moving from diagnosis alone into direct treatment.
The basic principle of image-guided procedures
The core idea is working while seeing. Doctors check the target and the nearby vessels and organs on imaging, insert the instrument, and keep confirming its position throughout.
Plan the target and the access route on imaging.
Give local anaesthesia and make a small entry point in the skin.
Move the catheter or needle to the target while watching the images.
Confirm the position again, then perform the test or treatment.
Remove the instrument and press or close the entry site.
The role of CT, ultrasound, and other imaging
The equipment depends on the target area and the type of procedure, and several may be used together.
X-ray fluoroscopy and angiography: show a catheter moving through blood vessels in real time.
CT: shows the body in cross-sections, used to place needles in deep organs or lung lesions.
Ultrasound: real-time images without radiation, often used for the liver, thyroid, and kidneys.
MRI: used at some institutions for specific purposes.
Example of CT equipment. Not an actual procedure.
Procedures using a catheter
A small opening is made in a blood vessel at the wrist or groin, and a thin tube about 1 to 2 mm across is guided along the vessels to the target.
After contrast dye shows the vessel shape, doctors may inject medicine, place material that blocks a vessel (embolic material), or widen a narrowed vessel.
Example of X-ray fluoroscopy equipment. Not an actual procedure.
Procedures using a needle
A needle is passed through the skin directly to the target. Doctors advance it slowly while checking the needle tip on imaging.
Biopsy: a small piece of tissue is taken for pathology diagnosis.
Drainage: fluid, pus, or blocked bile is drained out of the body.
Local ablation: tumour tissue is destroyed with energy such as radiofrequency (RFA), microwave, or freezing.
Vascular interventions
IVR performed from inside the blood vessels is called vascular intervention.
Transarterial chemoembolization (TACE): anticancer drugs and embolic material are delivered into the artery feeding a liver cancer.
Embolization for bleeding: a bleeding vessel is blocked from the inside to stop it.
Angioplasty and stents: narrowed or blocked vessels are opened with a balloon or metal mesh.
Central venous port placement: a line for chemotherapy is placed under the skin.
Non-vascular interventions
These procedures reach organs or lesions directly with a needle or tube without going through blood vessels.
Percutaneous biopsy
Biliary, kidney, and abscess drainage
Radiofrequency ablation (RFA), microwave ablation, cryoablation
Bone cement injection (vertebroplasty)
Nerve blocks for pain relief
Common clinical applications of IVR
These are typical uses described in the medical literature. Whether any of them applies is decided by the doctors who examine the patient.
Chemoembolization for hepatocellular carcinoma
Image-guided biopsy of lung, liver, kidney, and bone lesions
Local ablation of small liver, kidney, and lung tumours
Drainage when a tumour blocks the bile duct or ureter
Embolization for tumour bleeding
Nerve blocks to reduce cancer pain
Features and limitations of IVR
IVR leaves small wounds, and recovery is often relatively quick depending on the procedure. Some procedures are done without general anaesthesia.
It cannot be used for every lesion. Effects and risks vary with the lesion’s location and size, the vessel anatomy, and the patient’s overall condition. In many cases it is considered alongside surgery, chemotherapy, or radiotherapy rather than in place of them. Procedures use radiation and contrast dye, and results are also affected by the team’s experience and equipment.
Possible complications
IVR is a medical procedure and complications can occur. How often and how serious they are varies widely with the procedure and the patient. Ask your medical team for a specific explanation beforehand.
Bleeding or haematoma
Bleeding can occur at the entry site or inside the organ.
Infection
The entry site or treated organ can become infected.
Vessel injury
A catheter can damage a vessel wall or cause a clot.
Contrast reactions
Allergic reactions such as hives, or reduced kidney function, can occur.
Post-embolization syndrome
Fever, pain, and nausea can last for several days after embolization.
Non-target embolization
Embolic material can flow into an unintended vessel and affect other tissue.
Radiation effects
Long procedures can cause radiation-related skin changes.
Organ-specific complications
For example, pneumothorax after lung procedures or bile duct injury after liver procedures.
Frequently asked questions
Is IVR surgery?
It is a procedure done with needles or catheters while watching images, without a large incision. Anaesthesia and hospital stay depend on the procedure and the institution.
Does it hurt?
Most procedures use local anaesthesia, sometimes with sedation. Pain during and after varies by procedure and person.