Traumatic penetrating knife injury to left face and skull base with significant metallic artefacts.
The knife enters the left cheek with associated haemorrhage and soft tissue swelling, and it passes inferior to the zygomatic arch and through the left mandibular coronoid process resulting in a comminuted fracture of the coronoid process.
The knife then passes the left lateral pterygoid plate and fractures it. It then passes through the left paramedian inferior clivus into the foramen magnum, with a resultant skull base fracture.
Tip of the knife is just to the right of midline in the anterior aspect of the posterior fossa, likely within the pretontine or cervicomedullary cistern. Knife tip entry into the parenchyma of the adjacent brainstem is not able to be assessed due to the artefact.