Differentiation Between Subdural Hematoma and Epidural Hematoma

　　Epidural hematoma and subdural hematoma are both commonly caused by head trauma. They can be differentiated based on several factors, including source of bleeding, location of the hematoma, clinical presentation, CT imaging features, and treatment principles. If you experience any discomfort, seek medical attention promptly.

　　1. Different Sources of Bleeding

　　Subdural hematomas most commonly result from rupture of bridging veins on the brain surface; less frequently, they may arise from hemorrhage associated with cerebral contusions or lacerations. Epidural hematomas primarily originate from injury to the middle meningeal artery or its branches due to skull fracture; they may also result from venous sinus or diploic vein rupture.

　　2. Different Locations of Hematoma

　　Subdural hematomas occur in the subdural space—i.e., between the dura mater and arachnoid mater—and tend to be extensive, often covering the entire cerebral hemisphere surface or appearing as a crescent-shaped collection. Epidural hematomas occur in the epidural space—i.e., between the inner table of the skull and the dura mater—and are typically localized near the site of skull fracture, commonly presenting as lens-shaped (biconvex) or spindle-shaped collections.

　　3. Different Clinical Presentations

　　Subdural hematomas often have an insidious onset, especially in chronic cases. Patients commonly present with symptoms of increased intracranial pressure—including headache, dizziness, nausea, and vomiting—as well as neuropsychiatric manifestations such as memory impairment, cognitive decline, and behavioral or psychiatric abnormalities. In contrast, patients with epidural hematomas typically experience a brief period of loss of consciousness immediately after injury (primary coma), followed by a lucid interval. As the hematoma expands and intracranial pressure rises, patients deteriorate neurologically, developing recurrent impaired consciousness along with headache, vomiting, pupillary changes, and, in severe cases, herniation syndromes.

　　4. Different CT Imaging Features

　　On CT imaging, subdural hematomas appear as crescent- or half-moon–shaped hyperdense (or occasionally isodense or hypodense) lesions beneath the inner table of the skull. Epidural hematomas appear as well-demarcated, biconvex (lens-shaped) or spindle-shaped hyperdense lesions located between the inner skull table and the dura mater; their density is usually homogeneous, and they typically do not cross suture lines.

　　5. Different Treatment Principles

　　Acute subdural hematomas constitute a neurosurgical emergency and generally require urgent surgical evacuation. Chronic subdural hematomas are commonly treated with burr-hole drainage, which yields favorable outcomes and relatively good prognosis. For acute epidural hematomas, immediate surgical intervention is indicated if the hematoma volume is large or if signs of markedly elevated intracranial pressure or herniation are present. Conversely, small epidural hematomas without significant clinical symptoms may be managed conservatively.

　　During treatment, patients should follow a light, bland diet and avoid spicy or irritating foods—such as garlic, spicy hotpot, and wasabi. Adequate rest is essential, and overexertion should be avoided to support recovery and maintain overall health.