Postoperative subdural haematoma and pneumocephalus mimicking TIA

An 86-year-old man presented with left hand numbness and weakness 10 days after a resection of squamous cell carcinoma of the right side of the scalp. A CT head scan identified a right-sided, hypodense subdural collection without midline shift, with associated pneumocephalus. When the images were reviewed on bony settings, minute drill holes were identified penetrating the outer tables as expected, but also the inner table of the calvarium. With this knowledge, the initial clinical diagnosis altered significantly from that of a transient ischaemic attack to a working diagnosis of a subdural haematoma as a complication of the penetrating injury to the cranium, in a patient with an elevated international normalised ratio.