Even though they share the same name, “Subarachnoid Hemorrhage,” the traumatic (tSAH) and non-traumatic (aneurysmal rupture) types differ significantly in cause, symptom severity, and urgency.
Non-traumatic cases often present with the “worst headache of your life” and require immediate surgery to secure a ruptured aneurysm, carrying a high mortality rate. In contrast, tSAH is caused by physical trauma, often involves minor bleeding, and is typically managed conservatively. This article compares the two based on the source of bleeding, CT scan patterns, re-bleeding risks, and the necessity of emergency surgery.
Comparison: Traumatic (tSAH) vs. Spontaneous Subarachnoid Hemorrha
| Feature | Traumatic SAH (tSAH) | Spontaneous (Aneurysmal) SAH |
| Cause | Rupture of small surface vessels or bleeding from a cerebral contusion due to a blow to the head. | Rupture of a cerebral aneurysm (accounts for approx. 80% of cases). |
| Bleeding Pattern | Minor bleeding appearing as hazy white lines along the sulci (brain grooves). Does not usually spread throughout the brain. | Massive bleeding concentrated in the basal cisterns (deep brain spaces), often spreading extensively. |
| Onset/Symptoms | Symptoms center on the trauma itself. Headache is mild to moderate. Consciousness depends on concurrent injuries. | Sudden, “thunderclap headache” (the worst ever). Often accompanied by immediate loss of consciousness or deep coma. |
| Re-bleeding Risk | Almost none. Once the bleeding stops, it does not typically recur. | Extremely high. Risk of re-rupture within the first 24 hours is high and often fatal. |
| Main Treatment | Conservative management (rest, symptomatic relief). Surgery is only for associated injuries (e.g., subdural hematoma). | Emergency surgery (Craniotomy/Clipping) or Endovascular treatment (Coiling) to secure the aneurysm is mandatory. |
| Complications | Delayed hydrocephalus, mild vasospasm. | Severe cerebral vasospasm (can cause fatal strokes) and hydrocephalus. |
| Prognosis | Relatively good (if isolated). Outlook depends on the severity of associated cerebral contusions. | Very poor. Even with rapid treatment, approx. 50% of cases result in death or severe disability. |
Critical Diagnostic Differences
| Feature | Traumatic SAH (tSAH) | Spontaneous (Aneurysmal) SAH |
| Intracranial Lesions | Often associated with cerebral contusions or acute subdural hematomas. | Usually no other lesions; the aneurysm is the sole cause. |
| CT Appearance | Bleeding is often limited to the brain surface or the top (convexity) of the head. | Bleeding is widespread and concentrated in the deep base of the brain (basal cisterns). |
| Vessel Imaging | Emergency angiography (CTA/DSA) is usually unnecessary. | Emergency angiography is essential to locate the ruptured aneurysm. |
Summary
- tSAH: Caused by trauma. Typically involves low-volume bleeding with a relatively good prognosis. Management focuses on rest and observation.
- Spontaneous SAH: Caused by a ruptured aneurysm. Symptoms are severe, and emergency surgery is required to save lives. It is a highly fatal condition.
While both involve bleeding in the same space, they are treated as entirely different clinical entities based on whether trauma was involved.
