Visual Diagnosis in Emergency Medicine MOUNT FUJI SIGN: TENSION PNEUMOCEPHALUS IN THE EMERGENCY DEPARTMENT Daniel R. Lasoff, MD, Gabriel Wardi, MD, and Christian Sloane, MD Department of Emergency Medicine, University of California San Diego, San Diego, California Reprint Address: Daniel R. Lasoff, MD, Department of Emergency Medicine, University of California San Diego, 200 W. Arbor Drive #8676, San Diego, CA 92103 CASE REPORT A 59-year-old man with a history of Graves’ disease and diabetes presented to our emergency department with complaints of headache and vomiting. He had undergone surgical orbital decompression of his left eye for Graves’ exophthalmos the previous day. On examination, the patient was somnolent with fixed-gaze palsy in his left eye. Pupils were reactive bilaterally. His vitals were unremarkable. The patient’s computed tomography (CT) images are shown in Figures 1 and 2. Figure 1. Bone windows of the computed tomography scan demonstrating the Mount Fuji sign. Figure 2. Brain windows demonstrating the Mount Fuji sign. Arrowheads point at the characteristic twin-peak appear- ance of the frontal lobe. RECEIVED: 20 January 2019; FINAL SUBMISSION RECEIVED: 27 February 2019; ACCEPTED: 29 June 2019 1 The Journal of Emergency Medicine, Vol. -, No. -, pp. 1–2, 2019 Ó 2019 Elsevier Inc. All rights reserved. 0736-4679/$ - see front matter https://doi.org/10.1016/j.jemermed.2019.06.051