Seroma

Seromas are collections of serous fluid that usually occur as a complication of surgery, but can also be seen post-trauma. They are commonly seen as an early complication of breast surgery, where a potential space is left.

Terminology

Seromas are distinct from hematoma as they contain almost no red blood cells, and are not abscesses as they are sterile fluid collections.

Pathology

Serous fluid can refer to any clear proteinaceous fluid in the body. It was named after having been identified as fluid secreted from serous glands such the parotid. It is similar to effusions that are found elsewhere.

Seroma formation is thought to occur as plasma from local hemorrhage and other serous fluid accumulates at the site of tissue removal or disruption from surgery or trauma. The fluid collects within scar tissue and can accumulate to a large size causing discomfort and/or can be unsightly.

Radiographic features

Ultrasound
  • anechoic (i.e. simple) fluid collections
  • as maturation occurs, thickened nodular margins may develop

Differential diagnosis