Cardiovascular and Interventional Radiological Society of Europe

Obstruction relief

What is obstruction relief?

Occasionally, tumours grow so large that they block up the normal pathways in the body that should remain open, such as the biliary tree, the digestive tract, the airway or the urinary tract. This blockage causes fluids tto build up in certain areas or organs within the body. If left untreated, the blockage and resulting fluid collection may cause pain, infection and organ failure.

There are a number of minimally invasive techniques available to relieve the obstruction. These techniques aim to drain the fluid collections or bypass the blockage with tubes or stents.

How does the procedure work?

There are two types of minimally invasive techniques available: Image-guided drainage of collections or balloon dilatation with or without stenting.

Image-guided drainage is a minimally invasive method which involves using a catheter (a thin, flexible tube) to drain a fluid collection or abscess. The procedure is carried out under image guidance; the type of imaging used depends on the location of the fluid collection. You will receive local anaesthetic or be sedated for the procedure.

Alternatively, the blocked structure can be opened using minimally invasive devices. These include balloons ,stents (metal mesh tubes ) or a combination of both. The balloons can help open up the narrowed path when inflated and the stent can provide support to keep the path open. Once the blockage is relieved, the built-up fluid can drain normally along the re-opened pathway

Why perform it?

If left untreated, such obstructions and the resulting fluid can cause pain, infection and organ failure.

What are the risks?

These procedures are overall safe but there can be some risks. In 2-5% of cases, bacteria can enter the bloodstream. Septic shock, in which organs fail as a result of infection or bacteria in the blood, occurs in 1-2% of cases. Other risks include bleeding and rupture of the organ that is being ballooned-up. Some patients experience stent migration, in which the stent travels to another part of the body, or re-obstruction, meaning the treated structure becomes blocked again. If you have a re-obstruction, you may need to undergo further treatment.


1. Society of Cardiovascular and Interventional Radiology Standards of Practice Committee. Quality improvement guidelines for adult percutaneous abscess and fluid drainage. J Vasc Intervent Radiol 1995; 6:68-90.