Sensitivity of the Mount Fuji Sign After Evacuation of Chronic Subdural Hematoma in Nonagenarians

Background The Mount Fuji sign (MFS) is a radiological sign on computed tomographic scans depicting air between the frontal lobes. Air in this location indicates tension pneumocephalus (TP), considered a neurosurgical emergency.We evaluate the correlation between the MFS and perioperative mortality attributed to TP in nonagenarians who have undergone evacuation of chronic subdural hemorrhage (cSDH). Materials and methods We retrospectively reviewed the records of nonagenarians who had cSDH evacuation between 2006 and 2015. Postoperative computed tomographic images were evaluated for findings consistent with the MFS. Results Of 45 patients, 15 patients (33%) had radiological MFS, and 3 patients (20%) with MFS required reoperation because of new blood collection. No patient required reoperation because of TP. Perioperative (30-day) mortality in patients demonstrating the MFS was 6.67% caused by cardiac arrhythmia versus 13.33% mortality in patients with no evidence of the MFS. Conclusion Mount Fuji sign in nonagenarians after cSDH evacuation is not a specific sign of TP.