Treatment of a subdural hematoma depends on its size and rate of growth. Some small subdural hematomas can be managed by careful monitoring until the body heals itself. Other small subdural hematomas can be managed by inserting a temporary small catheter through a hole drilled through the skull and sucking out the hematoma; this procedure can be done at the bedside. Large or symptomatic hematomas require a craniotomy, the surgical opening of the skull. A surgeon then opens the dura, removes the blood clot with suction or irrigation, and identifies and controls sites of bleeding. Postoperative complications include increased intracranial pressure, brain edema, new or recurrent bleeding, infection, and seizure. The injured vessels must be repaired.

Depending on the size and deterioration, age of the patient, and anaesthetic risk posed, subdural hematomas occasionally require craniotomy for evacuation; most frequently, simple burr holes for drainage; often conservative treatment; and rarely, palliative treatment in patients of extreme age or with no chance of recovery.

In those with a chronic subdural hematoma, but without a history of seizures, the evidence is unclear if using anticonvulsants is harmful or beneficial.

Treatment has traditionally been splenectomy. However, splenectomy is avoided if possible, particularly in children, to avoid the resulting permanent susceptibility to bacterial infections. Most small, and some moderate-sized lacerations in stable patients (particularly children) are managed with hospital observation and sometimes transfusion rather than surgery. Embolization, blocking off of the hemorrhaging vessels, is a newer and less invasive treatment. When surgery is needed, the spleen can be surgically repaired in a few cases, but splenectomy is still the primary surgical treatment, and has the highest success rate of all treatments.

Small breast hematomas that cause no discomfort often require merely clinical observation, with ultrasound being used to monitor the resolution of the hematoma.

Large breast hematomas, or those that are not becoming smaller or that are causing discomfort, usually require drainage. Also hematomas that occur after surgery for excision of a malignant tumor are drained, because a hematoma to which irradiation is applied is unlikely to ever resolve. A recent hematoma can be drained by means of needle aspiration or (rarely) open surgical drainage.

It has been suggested that suction drains placed during surgery and non-peritonisation (not closing the posterior peritoneum) may reduce the possibility of lymphocele development.

Smaller lymphoceles can be managed expectantly, and many lesions will regress over time. For symptomatic lesions a number of approaches are available and include fine needle aspiration with US or CT guidance, catheter insertion and drainage (with possible use of sclerosants), and surgical drainage. Sex and masturbation may cause the lymphocele to grow if it is in the genital area. It is suggested to avoid these activities for around one to one and a half months. Some exercises may also help to shrink it.

As with other types of intracranial hematomas, the blood may be removed surgically to remove the mass and reduce the pressure it puts on the brain. The hematoma is evacuated through a burr hole or craniotomy. If transfer to a facility with neurosurgery is prolonged trephination may be performed in the emergency department.

Management consists of vigilant observation over days to detect progression. The subgaleal space is capable of holding up to 50% of a newborn baby's blood and can therefore result in acute shock and death. Fluid bolus may be required if blood loss is significant and patient becomes tachycardic. Transfusion and phototherapy may be necessary. Investigation for coagulopathy may be indicated.

Treatment depends substantially of the type of ICH. Rapid CT scan and other diagnostic measures are used to determine proper treatment, which may include both medication and surgery.

- Tracheal intubation is indicated in people with decreased level of consciousness or other risk of airway obstruction.

- IV fluids are given to maintain fluid balance, using isotonic rather than hypotonic fluids.

Since cerebral swelling presents a danger to the patient, treatment of cerebral contusion aims to prevent swelling. Measures to avoid swelling include prevention of hypotension (low blood pressure), hyponatremia (insufficient sodium), and hypercapnia (increased carbon dioxide in the blood). Due to the danger of increased intracranial pressure, surgery may be necessary to reduce it. People with cerebral contusion may require intensive care and close monitoring.

Treatment for light bruises is minimal and may include RICE (rest, ice, compression, elevation), painkillers (particularly NSAIDs) and, later in recovery, light stretching exercises. Particularly, immediate application of ice while elevating the area may reduce or completely prevent swelling by restricting blood flow to the area and preventing internal bleeding. Rest and preventing re-injury is essential for rapid recovery. Applying a medicated cream containing mucopolysaccharide polysulfuric acid (e.g., Hirudoid) may also speed the healing process. Other topical creams containing skin-fortifying ingredients, including but not limited to retinol or alpha hydroxy acids, such as DerMend, can improve the appearance of bruising faster than if left to heal on its own.

Very gently massaging the area and applying heat may encourage blood flow and relieve pain according to the gate control theory of pain, although causing additional pain may indicate the massage is exacerbating the injury. As for most injuries, these techniques should not be applied until at least three days following the initial damage to ensure all internal bleeding has stopped, because although increasing blood flow will allow more healing factors into the area and encourage drainage, if the injury is still bleeding this will allow more blood to seep out of the wound and cause the bruise to become worse.

In most cases hematomas spontaneously revert, but in cases of large hematomas or those localized in certain organs ("e.g.", the brain), the physician may optionally perform a puncture of the hematoma to allow the blood to exit.

Most arachnoid cysts are asymptomatic and do not require treatment. Treatment may be necessary when symptomatic. A variety of procedures may be used to decompress (remove pressure from) the cyst.

- Surgical placement of a cerebral shunt:

- An internal shunt drains into the subdural compartment.

- A cystoperitoneal shunt drains to the peritoneal cavity.

- Craniotomy with excision

- Various endoscopic techniques are proving effective, including laser-assisted techniques.

- Drainage by needle aspiration or burr hole.

- Capsular resection

- Pharmacological treatments may address specific symptoms such as seizures or pain.

Treatment most commonly involves the removal of the complete lesion during a single procedure, via the frontonasal bone flaps; recurrence is likely. Ablation treatment with an looks to be a possibility for permanent removal.

Some success has been seen using intralesional injections of formalin, performed by endoscopy.

Surgery is required if the hematoma is greater than , if there is a structural vascular lesion or lobar hemorrhage in a young patient.

- A catheter may be passed into the brain vasculature to close off or dilate blood vessels, avoiding invasive surgical procedures.

- Aspiration by stereotactic surgery or endoscopic drainage may be used in basal ganglia hemorrhages, although successful reports are limited.

If diagnosed within the first few hours of presentation, the pooling blood may be evacuated using a syringe. Once the blood has clotted, removal by this method is no longer possible and the clot can be removed via an incision over the lump under local anesthetic. The incision is not stitched, but will heal very well. Care needs to be taken in regard to bleeding from the wound and possible infection with fecal bacteria. If left alone it will usually heal within a few days or weeks. The topical application of a cream containing a Heparinoid is often advised to clear the clot .

To treat a septal haematoma it is incised & drained to prevent avascular necrosis of the septal hyaline cartilage which depends on diffusion of nutrients from its attached nasal mucosa. Small hematomas can be aspirated with a wide-bore needle. Large hematomas are drained by an incision parallel to nasal floor. Systemic antibiotics are given after the incision and drainage to prevent local infection.

Most arachnoid cysts are asymptomatic, and do not require treatment. Where complications are present, leaving arachnoid cysts untreated, may cause permanent severe neurological damage due to the progressive expansion of the cyst(s) or hemorrhage (bleeding). However, with treatment most individuals with symptomatic arachnoid cysts do well.

More specific prognoses are listed below:

- Patients with impaired preoperative cognition had postoperative improvement after surgical decompression of the cyst.

- Surgery can resolve psychiatric manifestations in selected cases.

Prognosis for this condition varies according to extent of the hematoma, but is normally fairly good. Smaller hematomae carry a 99% chance of full recovery, with larger ones carrying a recovery rate ranging from 80 to 90%. Occasional epistaxis may follow the surgery, but this is temporary and should subside within 2 to 3 weeks after surgery.

Some hematomas are visible under the surface of the skin (commonly called bruises) or possibly felt as masses/lumps. Lumps may be caused by the limitation of the blood to a sac, subcutaneous or intramuscular tissue space isolated by fascial planes. This is a key anatomical feature that helps prevent injuries from causing massive blood loss. In most cases the hematoma such as a sac of blood eventually dissolves; however, in some cases they may continue to grow such as due to blood seepage or show no change. If the sac of blood does not disappear, then it may need to be surgically cleaned out/repaired.

The slow process of reabsorption of hematomas can allow the broken down blood cells and hemoglobin pigment to move in the connective tissue. For example, a patient who injures the base of his thumb might cause a hematoma, which will slowly move all through the finger within a week. Gravity is the main determinant of this process.

Hematomas on articulations can reduce mobility of a member and present roughly the same symptoms as a fracture.

In most cases, movement and exercise of the affected muscle is the best way to introduce the collection back into the blood stream.

A mis-diagnosis of a hematoma in the vertebra can sometimes occur; this is correctly called a hemangioma (buildup of cells) or a benign tumor.

A hematoma (US spelling) or haematoma (UK spelling) is a localized collection of blood outside the 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 initially in liquid form spread among the tissues including in sacs between tissues where it may coagulate and solidify before blood is reabsorbed into blood vessels. An ecchymosis is a hematoma of the skin larger than 10mm.

They may occur among/within many areas such as skin and other organs, connective tissues, bone, joints and muscle.

A collection of blood (or even a hemorrhage) may be aggravated by anticoagulant medication (blood thinner). Blood seepage and collection of blood may occur if heparin is given via an intramuscular route; to avoid this, heparin must be given intravenously or subcutaneously.

It is not to be confused with hemangioma, which is an abnormal buildup/growth of blood vessels in the skin or internal organs.

A "subarachnoid hemorrhage" is bleeding into the subarachnoid space—the area between the arachnoid membrane and the pia mater surrounding the brain. Besides from head injury, it may occur spontaneously, usually from a ruptured cerebral aneurysm. Symptoms of SAH include a severe headache with a rapid onset ("thunderclap headache"), vomiting, confusion or a lowered level of consciousness, and sometimes seizures. The diagnosis is generally confirmed with a CT scan of the head, or occasionally by lumbar puncture. Treatment is by prompt neurosurgery or radiologically guided interventions with medications and other treatments to help prevent recurrence of the bleeding and complications. Since the 1990s, many aneurysms are treated by a minimal invasive procedure called "coiling", which is carried out by instrumentation through large blood vessels. However, this procedure has higher recurrence rates than the more invasive craniotomy with clipping.

Small breast hematomas often resolve on their own within several days or weeks by means of reabsorption of the blood. Larger hematomas are more likely to lead to inflammation or fibrosis.

Breast hematomas can sometimes lead to skin discoloration, inflammation, or fever. When a hematoma resolves, it may become fibrotic, leaving behind scar tissue. A resolving hematoma may liquify to form a seroma.

Post-surgical breast hematomas can also impede wound healing and therefore impact the cosmetic outcome. Hematomas are furthermore one of the risk factors for breast surgical site infections. There is preliminary evidence that, after breast implant surgery, the presence of hematoma increases the risk of developing capsular contracture.

In mammography screening, scar tissue resulting from a breast hematoma can easily be confused with tumor tissue, especially in the first years following surgery. Ultimately, fat necrosis may occur in the concerned region of the breast.

In TBI patients with epidural hematomas, prognosis is better if there was a lucid interval (a period of consciousness before coma returns) than if the patient was comatose from the time of injury. Unlike most forms of TBI, people with epidural hematoma and a Glasgow Coma Score of 15 (the highest score, indicating the best prognosis) are expected to make a good outcome if they can receive surgery quickly.

The risk of the development of a lymphocele is positively correlated to the extent of the removal of lymphatic tissue during surgery (lymphadenectomy). Surgery destroys and disrupts the normal channels of lymph flow. If the injury is minor, collateral channels will transport lymph fluid, but with extensive damage, fluid may accumulate in an anatomic space resulting in a lymphocele. Typical operations leading to lymphocysts are renal transplantation and radical pelvic surgery with lymph node removal because of prostatic or gynecologic cancer. Other factors that may predispose of lymphocele development are preoperative radiation therapy, heparin prophylaxis (used to prevent deep vein thrombosis), and tumor characteristics. After radical surgery for cervical and ovarian cancer studies with follow-up CT found lymphoceles in 20% and 32%, respectively. Typically they develop within 4 months after surgery.

Subungual hematomas are treated by either releasing the pressure conservatively when tolerable or by drilling a hole through the nail into the hematoma (trephining), or by removing the entire nail. Trephining is generally accomplished by using a heated instrument to pass through the nail into the blood clot. Removal of the nail is typically done when the nail itself is disrupted, a large laceration requiring suturing is suspected, or a fracture of the tip of the finger occurs. Although general anesthesia is generally not required, a digital nerve block is recommended to be performed if the nail is to be removed.

Subungual hematomas typically heal without incident, though infection or disruption of the nail (onycholysis) may occur.

Factors increasing the risk of a subdural hematoma include very young or very old age. As the brain shrinks with age, the subdural space enlarges and the veins that traverse the space must travel over a wider distance, making them more vulnerable to tears. This and the fact that the elderly have more brittle veins make chronic subdural bleeds more common in older patients. Infants, too, have larger subdural spaces and are more predisposed to subdural bleeds than are young adults. For this reason, subdural hematoma is a common finding in shaken baby syndrome. In juveniles, an arachnoid cyst is a risk factor for a subdural hematoma.

Other risk factors for subdural bleeds include taking blood thinners (anticoagulants), long-term alcohol abuse, dementia, and the presence of a cerebrospinal fluid leak.

There are many causes of subcutaneous hematomas including ecchymoses. Coagulopathies such as Hemophilia A may cause ecchymosis formation in children. The medication betamethasone can have the adverse effect of causing echhymosis.