A Case of Unilateral Sixth Cranial Nerve (CN VI) Avulsion in the Prepontine Cistern After Severe Head Trauma

The patient was a 46-year-old woman who presented with right sixth cranial nerve (CN VI) palsy following severe head trauma secondary to a motor vehicle collision one month prior. In this case report, we aim to add to the literature an additional example of unilateral CN VI avulsion as visualized by MRI secondary to head trauma. 3D T2 MRI was used to visualize the CN VI avulsion. CT was also used in the evaluation of head trauma. In our view, the force trajectory of the patient’s impact with the vehicle dashboard, as evidenced by the right occipital lobe fracture, explains the etiology of the unilateral right CN VI avulsion. The combination of clinical and imaging findings was central to the analysis of this case.