A seroma is a pocket of clear
serous fluid
In physiology, serous fluid or serosal fluid (originating from the Medieval Latin word ''serosus'', from Latin ''serum'') is any of various body fluids resembling serum, that are typically pale yellow or transparent and of a benign nature. The fl ...
(filtered
blood plasma
Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the ...
). They may sometimes develop in the body after
surgery, particularly after
breast surgery,
abdominal surgery
The term abdominal surgery broadly covers surgical procedures that involve opening the abdomen (laparotomy). Surgery of each abdominal organ is dealt with separately in connection with the description of that organ (see stomach, kidney, liver, etc ...
, and
reconstructive surgery
Reconstructive surgery is surgery performed to restore normal appearance and function to body parts malformed by a disease or medical condition.
Description
Reconstructive surgery is a term with training, clinical, and reimbursement implica ...
. They can be diagnosed by physical signs, and with a
CT scan
A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...
.
Seromas can be difficult to manage. Serous fluid may leak out naturally, and a persistent leak can cause problems. Fluid can be drained, including by inserting a
drain surgically. Seromas can be prevented through careful surgery, and drains can be inserted before they form. Patient posturing and position can reduce risk, as well as
breast binding
Breast binding, also known as chest binding, is the flattening of breasts with constrictive materials such as cloth strips, purpose-built undergarments, often using spandex or other synthetic fiber, and shirts layered from tight to loose. Binders ...
after breast surgery.
Etymology
Around 16th century CE, the word originated from french: séreux, meaning "watery" later the meaning changed to "of, secreting, or containing serum". It is directly derived from la, serosus, meaning "watery fluid, whey".
It was joined with a word-forming element from el, oma, with -o-, lengthened stem vowel + -ma suffix, especially taken in medical use as "
tumor
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
" or "
morbid
A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that ...
growth".
Classification
A seroma contains
serous fluid
In physiology, serous fluid or serosal fluid (originating from the Medieval Latin word ''serosus'', from Latin ''serum'') is any of various body fluids resembling serum, that are typically pale yellow or transparent and of a benign nature. The fl ...
.
This is composed of
blood plasma
Blood plasma is a light amber-colored liquid component of blood in which blood cells are absent, but contains proteins and other constituents of whole blood in suspension. It makes up about 55% of the body's total blood volume. It is the ...
that has seeped out of ruptured small blood vessels and the
inflammatory fluid produced by injured and dying cells. Seromas are different from
hematoma
A hematoma, also spelled haematoma, or blood suffusion is a localized bleeding outside of blood vessels, due to either disease or trauma including injury or surgery and may involve blood continuing to seep from broken capillaries. A hematoma is ...
s, which contain
red blood cell
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek ''erythros'' for "red" and ''kytos'' for "holl ...
s, and
abscesses, which contain
pus
Pus is an exudate, typically white-yellow, yellow, or yellow-brown, formed at the site of inflammation during bacterial or fungal infection. An accumulation of pus in an enclosed tissue space is known as an abscess, whereas a visible collection ...
and result from an
infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable d ...
. Serous fluid is also different from
lymph
Lymph (from Latin, , meaning "water") is the fluid that flows through the lymphatic system, a system composed of lymph vessels (channels) and intervening lymph nodes whose function, like the venous system, is to return fluid from the tissues ...
.
Signs and symptoms
A seroma can usually be felt as a hard mass under the skin.
This may cause
erythema
Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not asso ...
(skin redness).
They can also cause significant
pain
Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...
.
Cause
A seroma is usually caused by surgery. Seromas are particularly common after
breast surgery (e.g.,
mastectomy
Mastectomy is the medical term for the surgical removal of one or both breasts, partially or completely. A mastectomy is usually carried out to treat breast cancer. In some cases, women believed to be at high risk of breast cancer have the operat ...
),
abdominal surgery
The term abdominal surgery broadly covers surgical procedures that involve opening the abdomen (laparotomy). Surgery of each abdominal organ is dealt with separately in connection with the description of that organ (see stomach, kidney, liver, etc ...
, and
reconstructive surgery
Reconstructive surgery is surgery performed to restore normal appearance and function to body parts malformed by a disease or medical condition.
Description
Reconstructive surgery is a term with training, clinical, and reimbursement implica ...
. It can also be seen after
neck surgery
Otorhinolaryngology ( , abbreviated ORL and also known as otolaryngology, otolaryngology–head and neck surgery (ORL–H&N or OHNS), or ear, nose, and throat (ENT)) is a surgical subspeciality within medicine that deals with the surgical a ...
,
thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The t ...
and
parathyroid
Parathyroid glands are small endocrine glands in the neck of humans and other tetrapods. Humans usually have four parathyroid glands, located on the back of the thyroid gland in variable locations. The parathyroid gland produces and secretes ...
surgery, and
hernia repair.
The larger the surgical intervention, the more likely that seromas form. Early or improper removal of sutures can sometimes lead to formation of seroma or discharge of serous fluid from operative areas. Seromas can also sometimes be caused by injury, such as when the initial swelling from a blow or fall does not fully subside. The remaining
serous fluid
In physiology, serous fluid or serosal fluid (originating from the Medieval Latin word ''serosus'', from Latin ''serum'') is any of various body fluids resembling serum, that are typically pale yellow or transparent and of a benign nature. The fl ...
causes a seroma that the body usually absorbs gradually over time (often taking many days or weeks), but a knot of calcified tissue sometimes remains. Large seromas take longer to resolve than small ones, and they are more likely to undergo
secondary infection
An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable di ...
. A seroma may persist for several months,
or even years as the surrounding tissue hardens.
Seroma is the most common surgical complication after breast surgery. It is due to the presence of rich lymphatic system in the breast, low fibrinogen levels in lymph fluid and potential space creation in the breast after surgery, which contributes to seroma formation. Seroma is more common in older and obese people.
Diagnosis
A seroma may be diagnosed based on signs on the skin.
On
CT scan
A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...
s, seromas have a
radiodensity of 0–20
Hounsfield units, generally in the lower part of this range, consistent with clear fluid.
Prevention
Surgical
Gentle surgical technique with careful and meticulous control of bleeding helps avoid seromas.
Liposuction contributes to seroma formation when it is done in conjunction with creating a "flap" and potential space is confluent with the treated area. Controversy exists in
tummy tuck surgery as to whether electrosurgical dissection either contributes to serum formation or prevents it.
Drains are traditionally used, but their use has been challenged by various authors who believe quilting sutures alone may be sufficient to reach results as good as or better than when using drains. Seromas accumulate in what is known as "dead space" where a potential place for the fluid exists. Efforts are directed at reducing or eliminating the dead space. Quilting sutures reduce the risk of the skin–fat layer's separating from the deeper muscle layer, and having the separation fill up with fluid, by physically holding those layers together. Drains suck the two layers together so the body's natural "glue" (
fibrin
Fibrin (also called Factor Ia) is a fibrous, non-globular protein involved in the clotting of blood. It is formed by the action of the protease thrombin on fibrinogen, which causes it to polymerize. The polymerized fibrin, together with pla ...
) and wound healing have a chance for a permanent bond.
Nonsurgical
Prevention of movement between the layers allows the tentative initial bond of fibrin to be reinforced by wound healing with a thin, strong, layer of scar. Avoiding certain positions for certain surgeries may have an effect. (In abdominoplasty, sitting upright with the knees bent and hips flexed will cause pressure across the lower abdomen and a tendency to seroma formation. The patient is best to stand or at least be semirecumbent). External pressure may help in immobilization, but also is thought to reduce the tendency of the fluid to leak out of vessels by increasing the backpressure on those fluid sources. Following breast augmentation or double mastectomy,
binding the chest may be recommended for several weeks to minimize the risk of seromas.
Treatment
Seromas may be difficult to manage at times. Quilting (inserting interrupted deep stitches in the wound) after mastectomy probably significantly reduces seroma formation.
Fine-needle aspiration
Fine-needle aspiration (FNA) is a diagnostic procedure used to investigate lumps or masses. In this technique, a thin (23–25 gauge (0.52 to 0.64 mm outer diameter)), hollow needle is inserted into the mass for sampling of cells that, aft ...
is a common procedure.
However, it is controversial: it is recommended by some for the reason that a seroma can be a culture medium for bacteria, whereas others advise it only for collection of excessive amounts of fluid, because even an aspiration carried out under aseptic conditions carries a certain risk of infection. Depending on its volume and duration, control of a leak may take up to a few weeks to resolve with aspiration of
serua and the application of pressure dressings.
Manual lymphatic drainage conducted by a trained professional can also assist in managing and treating seromas.
If a serum or leak does not resolve (e.g., after a
soft tissue
Soft tissue is all the tissue in the body that is not hardened by the processes of ossification or calcification such as bones and teeth. Soft tissue connects, surrounds or supports internal organs and bones, and includes muscle, tendons, liga ...
biopsy
A biopsy is a medical test commonly performed by a surgeon, interventional radiologist, or an interventional cardiologist. The process involves extraction of sample cells or tissues for examination to determine the presence or extent of a d ...
), taking the patient back to the operating room may be necessary to place some form of closed-suction
drain into the wound.
In case of
lumpectomy, the formation of a seroma at the lumpectomy site has been cited in medical literature as being beneficial, with claims that it can contribute to preserve the contour of the breast.
Seromas are a treatment target in partial breast-radiation therapy.
[
] In some cases, a seroma may need to be drained prior to a course of radiotherapy adjuvant to surgery.
See also
*
Lymphocele
*
Sialocele
References
{{Reflist, 30em
Gross pathology