Tension Pneumocephalus Secondary to Frontal Sinusotomy in a Dog

Air accumulation in the cranial cavity is referred to as pneumocephalus. Tension pneumocephalus is a neurosurgical emergency that can cause headaches, seizures, reduced consciousness, and even death owing to increased intracranial pressure. We report a case of tension pneumocephalus. The patient underwent a frontal sinusotomy for a mass invading the frontal sinus and nasal cavity. One month later, the patient was admitted to the emergency room with seizures and neurotic symptoms, and computed tomography (CT) revealed tension pneumocephalus with significant gas dilatation of both lateral ventricles. Prompt treatment of the dural defect resulted in the immediate improvement of neurological signs. A CT re-examination 1 week after surgery showed that the pneumocephalus had completely resolved. Tension pneumocephalus should be considered a potential complication in patients with worsening neurological signs after skull base surgery. An accurate diagnosis requires an understanding of imaging features and a high index of suspicion, and immediate intervention is essential.