Image: Extensive Pneumocephalus.

A 53-year-old man was admitted to our hospital following a traffic accident. He had been riding a bicycle and was knocked down by a motorcycle, injuring the right side of his forehead. Upon arrival at our department, he was conscious and we found no cerebrospinal fluid rhinorrhea or otorrhea. His Glasgow Coma Scale score was 15. Neurologic examination was normal, except for reduced vision in his right eye. Head computed tomography showed extensive pneumocephalus involving the cisterna ambiens, prepontine and suprasellar cisterns, and temporal, frontal, parietal, and occipital lobes. A right frontal skull fracture was evident. The patient was treated conservatively, with bed rest with the head of the bed elevated at 30 degrees. The patient was instructed to avoid any movements that might increase intracranial pressure, and he was placed on conventional concentration oxygen therapy of about 40%. Repeat computed tomography 9 hours later showed partial absorption of the pneumocephalus, which was almost completely absorbed 4 days later. He recovered well and was discharged after 7 days. At the 1-month follow-up, the patient was well, although the reduced vision in his right eye persisted.