Case 3
History:
22 year-old man came to the hospital in a deep coma following a high-speed motor vehicle collision
Findings:
Gradient sequences MRI showing areas of susceptibility artifacts involving the gray white matter junction, corpus callosum and deep gray matter structures
Diagnosis:
Diffuse axonal injury (DAI)
Discussion:
Diffuse axonal injury (DAI) is secondary to severe head injury, and is considered as the main cause of morbidity and mortality of head injury. The mechanisms of DAI is rotational acceleration and/or angular acceleration resulting in shearing and tensile injury to axons and lead to axonal injury and small vascular damages.
Typically involve are cortico-medullary junctures, corpus callosum and caudal part of brain stem. T2*-weighted gradient-echo MR imaging is highly sensitive to blood degradation products.
References:
- Gieron MA, Korthals JK, Riggs CD. Diffuse axonal injury without direct head trauma and with delayed onset of coma. Pediatr Neurol. Nov1998;19(5):382.4
- Gleckman AM, Bell MD, Evans RJ, et al. Diffuse axonal injury in infants with nonaccidental craniocerebral trauma: enhanced detection by beta-amyloid precursor protein immunohistochemical staining. Arch Pathol Lab Med. Feb1999; 123(2):146-51.
- Gean AD. Imaging of Head Trauma.New York, NY: Raven Press;1994.
