Subdural Hematoma: Symptoms, Types, Causes and Treatment

Subdural hematoma is a medical condition that involves bleeding between the dura mater (the tough outer membrane covering the brain) and the arachnoid membrane. This space, known as the subdural space, can fill with blood due to trauma or other mechanisms, compressing brain tissue and leading to a variety of neurological symptoms. Subdural hematomas are commonly seen in elderly patients but can affect individuals of all ages. Early recognition, diagnosis, and management are crucial for optimal outcomes. This article provides a comprehensive overview of subdural hematoma symptoms, types, causes, and treatment options, based on up-to-date research and clinical evidence.

Symptoms of Subdural Hematoma

Recognizing the symptoms of a subdural hematoma is critical for timely diagnosis and intervention. The presentation can be subtle or dramatic, varying by the type and size of the hematoma, as well as patient age and overall health.

Symptom	Description	Frequency/Severity	Source(s)
Headache	Persistent, often worsening over time	Most common	1 6 10 14
Weakness	Limb weakness, sometimes one-sided	Common	1 4 14
Cognitive Change	Confusion, memory loss, disorientation	Frequent, especially elderly	1 4 14
Gait Problems	Balance disturbance, difficulty walking	Notable in chronic cases	1 4 14
Seizures	Sudden convulsions	Less common	14
Drowsiness	Lethargy, reduced alertness	Seen in severe cases	6 8 14
Speech Problems	Dysphasia, dysarthria	Occasionally reported	4
Parkinsonism	Rigidity, tremor, bradykinesia	Rare, usually chronic cases	4

Table 1: Key Symptoms

Understanding the Symptom Spectrum

The symptoms of a subdural hematoma are often insidious and can mimic other neurological disorders, especially in older adults. The most frequently reported symptom is a persistent headache, which may gradually worsen over days or weeks, particularly in chronic cases 1 6 10 14. Weakness, often affecting one side of the body (hemiparesis), is another common presentation and may be accompanied by changes in speech or coordination 4 14.

Cognitive and Behavioral Changes

Cognitive decline, including confusion, memory problems, and disorientation, is especially prominent in elderly patients. These changes may be mistaken for dementia or other age-related conditions, making clinical suspicion and imaging studies crucial for diagnosis 1 13 14.

Gait and Balance Disturbances

Chronic subdural hematoma frequently causes problems with balance and walking, sometimes leading to falls. This can create a vicious cycle, as falls are also a leading cause of subdural hematoma in older adults 1 4 14.

Less Common and Severe Presentations

Other symptoms include seizures, drowsiness, and even a sudden drop in consciousness if the hematoma exerts significant pressure on the brain 14. In rare situations, subdural hematoma can present with parkinsonian features such as tremor, rigidity, and bradykinesia due to compression of the basal ganglia 4. Speech problems, such as dysphasia and dysarthria, have also been reported in some cases 4.

Types of Subdural Hematoma

Subdural hematomas are categorized based on the timing of symptom onset relative to the injury or bleeding event. Understanding the types is essential for effective management and prognosis.

Type	Onset/Timing	Typical Features	Source(s)
Acute	Within 0–3 days	Rapid deterioration, severe	8 9
Subacute	4–21 days	Intermediate; sudden worsening	8
Chronic	>3 weeks	Gradual symptoms, elderly focus	1 2 6
Spinal	Variable	Back/neck pain, rare	3 12

Table 2: Types of Subdural Hematoma

Acute Subdural Hematoma

Acute subdural hematomas typically develop within the first 72 hours following head trauma. They are often associated with severe brain injury and rapid neurological decline, sometimes with a brief period of lucidity before sudden deterioration 8 9. Acute hematomas are life-threatening emergencies requiring immediate intervention.

Subacute Subdural Hematoma

Subacute cases emerge over 4 to 21 days after the initial injury. They can be deceptive, as the patient may initially appear stable but then experience a sudden worsening of neurological status during the second week 8. Subacute hematomas are often mistaken for chronic cases but tend to have a more dangerous course and require close monitoring or urgent surgical care.

Chronic Subdural Hematoma

Chronic subdural hematomas develop over several weeks, commonly in the elderly. The symptoms are subtle and progress gradually, making diagnosis challenging 1 2 6. Chronic cases may arise after seemingly minor trauma or even spontaneously, especially in patients with underlying risk factors.

Spinal Subdural Hematoma

Though rare, subdural hematomas can also develop along the spinal cord, presenting with back or neck pain, sensory changes, or paralysis 3 12. These cases can be easily misdiagnosed and often require MRI for confirmation.

Causes of Subdural Hematoma

Understanding the mechanisms and risk factors leading to subdural hematoma is crucial for prevention and tailored treatment.

Cause	Mechanism/Trigger	At-Risk Populations	Source(s)
Head Trauma	Rupture of bridging veins	All ages, especially elderly	2 6 14
Falls	Minor or major impact	Older adults	2 10 14
Anticoagulants	Impaired blood clotting	Elderly, cardiac patients	2 6
Coagulopathy	Bleeding disorders	Various	6 11
Spinal CSF Leak	Intracranial hypotension, venous tear	Younger adults	5 12
Aging Brain	Brain atrophy, increased space	Elderly	1 2 13
Spontaneous	No obvious trigger	All ages	12 14

Table 3: Common Causes

Traumatic Causes

The vast majority of subdural hematomas are caused by trauma—most often, the rapid acceleration or deceleration of the head leads to tearing of the small bridging veins that traverse the subdural space 2 6 14. This is especially true in motor vehicle collisions, sports injuries, and falls.

Anticoagulation and Coagulopathy

The widespread use of blood-thinning medications (anticoagulants and antiplatelets) in elderly populations increases the risk of subdural bleeding, even after minor head impacts 2 6. Other causes include inherited or acquired bleeding disorders.

Age-Related Vulnerability

Aging leads to brain atrophy, which increases the space between the brain and the skull, stretching the bridging veins and making them more susceptible to tearing 1 2 13. This explains the higher incidence of chronic subdural hematoma in older adults.

Spinal CSF Leak and Intracranial Hypotension

In some younger or middle-aged patients, chronic subdural hematoma may occur without any clear trauma. Recent studies have identified spinal cerebrospinal fluid (CSF) leaks as an under-recognized cause, leading to low intracranial pressure and subsequent venous bleeding 5 12.

Spontaneous and Other Causes

Occasionally, subdural hematomas arise without a clear cause, termed "spontaneous." Such cases may be associated with underlying medical conditions or undetected minor trauma 12 14.

Treatment of Subdural Hematoma

Treating subdural hematoma requires a nuanced approach based on the patient's clinical status, hematoma size, and underlying risk factors. Both surgical and nonsurgical options are available.

Treatment Option	Indication/Use	Outcome/Benefit	Source(s)
Burr-Hole Evacuation	Symptomatic, large, chronic	Gold standard, low recurrence	2 6 10 15
Closed Drainage	Adjunct to burr-hole	Reduces recurrence	10 15
Craniotomy	Complex/recurrent cases	For thick membranes/multiloculated	6
Twist Drill Craniostomy	Alternative to burr-hole	Equivalent efficacy	15
MMA Embolization	Recurrent or high-risk CSDH	Promising, lowers recurrence	2 16 17 18
Steroids/Medications	Nonsurgical/as adjunct	Role under investigation	6 11 18
Conservative/Observation	Asymptomatic, small hematomas	For high surgical risk	6 18

Table 4: Treatment Strategies

Surgical Treatments

The cornerstone of subdural hematoma management is surgical drainage for symptomatic or large hematomas. The most widely used technique is burr-hole evacuation, which involves drilling one or more small holes in the skull to drain the blood 2 6 10 15. Closed system drainage (inserting a drain through the burr hole) significantly reduces the risk of recurrence and is considered best practice 10 15. In certain cases, such as those with thick membranes or multiloculated hematomas, a larger craniotomy may be required 6.

Twist drill craniostomy is another minimally invasive option that has shown equivalent outcomes to burr holes in some studies 15. For subacute or acute subdural hematomas, timely surgical intervention may be lifesaving.

Middle Meningeal Artery (MMA) Embolization

A new and promising therapy is embolization of the middle meningeal artery (MMA), which supplies blood to the outer membrane of chronic subdural hematomas. By blocking this artery, MMA embolization aims to reduce or prevent recurrent bleeding 2 16 17 18. Early studies and meta-analyses have shown lower recurrence rates compared to conventional surgery, but further large-scale trials are needed to establish efficacy and long-term safety 16 17.

Nonsurgical and Adjunctive Treatments

For patients who are asymptomatic, have very small hematomas, or are at high surgical risk, conservative management with close observation is an option 6 18. Pharmacological treatments—such as corticosteroids (dexamethasone), tranexamic acid, or angiotensin-converting enzyme inhibitors—have been explored as adjuncts or alternatives, particularly in the elderly or those unfit for surgery 6 11 18. However, current evidence is insufficient for routine use, and these approaches remain under investigation.

Postoperative Care and Recurrence Prevention

Recurrence is a significant challenge in managing chronic subdural hematomas, occurring in up to one-third of cases depending on hematoma type and patient factors 2 7 10. Use of drains, careful surgical technique, and consideration of MMA embolization in select cases can reduce this risk 7 10 15 16. Follow-up imaging and monitoring are recommended, especially for high-risk or recurrent cases.

Conclusion

Subdural hematomas are complex brain injuries that span a spectrum of causes, presentations, and treatments.

Key takeaways:

• Symptoms range from subtle headaches and cognitive changes to rapid neurological decline and coma, depending on hematoma type.
• Types include acute, subacute, and chronic subdural hematomas, each with distinct clinical courses and urgencies.
• Causes are diverse: trauma (especially in the elderly), anticoagulant use, spontaneous CSF leaks, and underlying coagulopathies.
• Treatment must be tailored to the individual, with burr-hole drainage and closed system drainage as gold standards, MMA embolization as an emerging therapy, and nonsurgical options considered for select patients.

Early recognition and individualized care are essential for improving outcomes in patients with subdural hematoma. As research advances, especially in minimally invasive treatments and pharmacological adjuncts, management will continue to evolve to better serve a growing and diverse patient population.