Hematoma: Meaning in a Radiology Report

Hematoma

Also written as: haematoma, blood collection, hemorrhagic collection

A hematoma is a pool of blood that has collected outside the blood vessels, like a deep bruise, usually after an injury or surgery.

Seen on: CT, MRI, Ultrasound

How it reads in a report

A 5.1 x 2.3 cm hematoma within the left vastus lateralis muscle has decreased in size since the prior study.

What it means

When a blood vessel is damaged, blood can leak out and pool inside tissue, such as a muscle, under the skin or around an organ. That pool is a hematoma. Common causes are an injury, surgery, a needle procedure or blood-thinning medicine. Fresh and older blood look different on scans, so the radiologist can often tell roughly how old it is.

When it matters

Most hematomas are slowly reabsorbed over weeks, much like a bruise fades. Doctors look more closely at large ones, those that keep growing, and those pressing on nearby structures. Inside the skull, even a small hematoma gets close attention, because there is little spare room. A follow-up scan can confirm it is shrinking, and occasionally a large one is drained.

Questions to ask your doctor

How big is the hematoma, and is it getting smaller?
Is it related to my injury, surgery or blood-thinning medicine?
When should it be checked again, and what signs should I watch for?

General information, not medical advice. What a finding means for you depends on your symptoms, your history and the images themselves, so talk your results through with a doctor.