Solitary brainstem injury due to cervical-stretch stress: Case report

Abstract

Recently brainstem lesions after head injuries observed in magnetic resonance (MR) images are considered as not an exceptional phenomenon. Usually most of the cases of brainstem injuries were included with other brain contusions as a result of shearing head injuries. Solitary brainstem injury, however, is still considered as rare event and its developing mechanism remain also unclear.

A 56-year-old-male was involved in an accident collapse of tunnel. Neurological examination on arrival to our hospital revealed mild disorientation without apparent focal deficits. Computed tomography (CT) showed solo small contusion at medial upper pons without skull fracture. Cervical X-ray picture showed tear-drop fracture of C7 vertebral body and fracture of C6 lamina. After a little while, he went into a comatose state, which revealed anisocoric non-reactive pupils, both limitation of ocular movements and tetraparesis. Follow up brain CT showed marked enlargement of the contusional hematoma of pons extended to midbrain. Spinal cord injury could not be observed in cervical MRI. Conservative medical management was performed. Neurological status did not improved significantly after two months.

This rare injury was suggested to be the sole influence of the cervical hyperflexion. Present case implies that stretching force can lead to a solitary brainstem injury.