Traumatic brain injury (TBI) is a major public health issue, and intracranial hypertension in the acute phase remains a critical scientific issue. Many patients with acute closed TBI received conservative, non-surgical treatments at first, while 5%~19% of which develops intractable intracranial hypertension that requires emergent surgery. Therefore, it is of great clinical significance to identify patients who are at high risk of deterioration in the early stage. Previous studies have found that brain compliance is a contributive factor to intracranial pressure, and might serve in the development of intracranial hypertension after TBI. We made assumption that intracranial pressure has a negative relationship with brain compliance providing that the volume of hematoma remains constant. However, few studies have applied magnetic resonance elastography (MRE) in evaluating brain compliance in patients with TBI. Therefore, this study is designed to enroll patients with acute closed traumatic brain injury who are initially treated non-surgically. Magnetic resonance elastography (MRE) sequences are performed to non-invasively assess patients' brain compliances, in the hope of exploring the potential value of MRE biomarkers to predict the short-term outcome in patients with acute closed TBI who are initially receive non-surgical treatments.

Inclusion Criteria:

• Age 18-60 years old
• Acute closed traumatic brain injury within 7 days
• Not receiving surgical intervention according to the judgement of neurosurgeons
• Expected tolerance of magnetic resonance imaging (MRI) scan 7 days from injury

Exclusion Criteria:

• Vital organ failure: congestive heart failure, respiratory failure, renal failure (CKD≥stage 3), severe hepatic dysfunction (Child-Pugh stage B or C)
• Any central nervous system (CNS) pathology prior to injury: stroke, epilepsy, CNS tumour/infections, dementia or other neurodegenerative diseases
• CT reveals infratentorial hematoma
• Contraindications of MRI
• Currently enrolled in other researches

Patients with acute closed traumatic brain injury within 7 days will be enrolled in the study. Patients are conservatively managed (didn't receive surgery yet) according to the judgement of neurosurgeons.