Splenic embolization is a minimally invasive procedure that reduces or redirects blood flow to the spleen by deliberately blocking branches of the splenic artery. Rather than surgically removing the spleen, a specialist threads a thin catheter through a blood vessel (usually in the groin) and delivers tiny blocking agents into the artery that feeds the spleen. It’s used most often after traumatic injury to stop internal bleeding, or in people with liver cirrhosis whose enlarged spleen is destroying too many blood cells.
How the Procedure Works
The procedure is performed by an interventional radiologist using real-time X-ray imaging to guide a catheter from the groin up into the splenic artery. Once the catheter is in position, the radiologist injects embolic agents, materials designed to physically block blood flow in targeted vessels. The most commonly used agents are platinum coils (used in roughly 57% of cases), followed by tiny particles made from gelatin sponge or polyvinyl alcohol (about 36% of cases). Vascular plugs are another option.
There are two main approaches depending on the goal. In proximal embolization, the radiologist places coils or plugs in the main trunk of the splenic artery, upstream of the spleen itself. This lowers blood pressure within the spleen enough to let an injury heal, while a network of smaller collateral arteries from the stomach and pancreas keeps the organ alive. In distal (or selective) embolization, the catheter is advanced deeper into the specific branch where the bleeding or damage is located, and that vessel is blocked directly until blood flow stops completely at the injury site.
Why It’s Performed
The most common reason is blunt trauma to the spleen, typically from car accidents, falls, or sports injuries. When imaging reveals a significant splenic injury but the patient is stable enough to avoid emergency surgery, embolization can stop the bleeding while preserving the organ. In a large Italian study of 281 trauma patients, the procedure achieved technical success in 100% of cases, and only about 10% ultimately needed their spleen removed afterward.
The second major use is in people with liver cirrhosis. Cirrhosis causes high pressure in the portal vein, which forces the spleen to enlarge. An oversized spleen traps and destroys blood cells faster than normal, a condition called hypersplenism. This leads to dangerously low platelet counts (raising the risk of uncontrolled bleeding) and low white blood cell counts (weakening the immune system). Low platelets can also disqualify patients from surgeries or cancer treatments they need. Partial splenic embolization intentionally shuts down a portion of the spleen’s tissue, reducing the organ’s ability to destroy blood cells while leaving enough functional tissue to maintain immune protection.
Less commonly, embolization treats splenic artery steal syndrome in cirrhosis patients, where too much blood diverts through the splenic artery and starves the liver of adequate flow.
Embolization vs. Spleen Removal
The spleen plays an important role in fighting infections, particularly from encapsulated bacteria like pneumococcus and meningococcus. Removing it entirely leaves a person permanently vulnerable to overwhelming, life-threatening infections. Surgical removal also carries its own risks: hemorrhage during the operation, blood clots, pneumonia, and abscesses beneath the diaphragm.
Embolization offers a way to treat the problem while keeping the spleen at least partially functional. Because some healthy splenic tissue continues receiving blood through collateral vessels, the organ retains a degree of immune function that total removal eliminates. This is especially valuable in younger patients and those with cirrhosis, who already face heightened infection risks.
What Recovery Looks Like
The most predictable side effect is post-embolization syndrome: fever, nausea, and left-sided abdominal pain that typically appears within 24 to 72 hours after the procedure. This is a normal inflammatory response to tissue losing its blood supply, not a sign of complications. In embolization procedures generally, some form of this syndrome occurs in 60% to 80% of patients, and it usually resolves within a few days with supportive care like pain medication and fluids.
The median recovery time after splenic embolization for trauma is about 43 days. During the first three weeks, close monitoring is recommended to catch any infections early, since splenic abscesses tend to appear around 18 days post-procedure. A follow-up CT scan at roughly six weeks helps confirm the spleen has healed properly. During this recovery window, you should expect restrictions on physical activity, particularly anything that could jar or stress the abdomen.
Possible Complications
A systematic review of splenic embolization after blunt trauma found an overall complication rate of about 25%. Most complications were minor: fever occurred in 18% of patients, pleural effusion (fluid collecting around the lung) in 13%, and coil migration in about 4%. Major complications were less common but more serious. Rebleeding requiring further treatment happened in roughly 5% of cases, splenic infarction (where more tissue dies than intended) in about 5%, and abscess formation in 4%. Other rare complications include splenic atrophy, cysts, blood vessel damage at the catheter insertion site, and kidney problems from the contrast dye used during imaging.
Vaccination and Infection Prevention
Even though the spleen is preserved, embolization can reduce its immune function enough to raise the risk of serious bacterial infections. Clinical guidelines group patients who have undergone splenic artery embolization alongside those with other forms of reduced splenic function. These patients should be current on routine vaccinations and typically receive additional pneumococcal and meningococcal vaccines, along with an annual flu shot. For planned procedures, these vaccinations are ideally given at least two weeks beforehand. Some patients also receive prophylactic antibiotics on a case-by-case basis, particularly after trauma when vaccination timing may not be ideal.