Mystery Case: Hypoglossal nerve palsy in occipito-temporal pneumatization

A 47-year-old man, with a 25-year history of fre-quent scuba diving, presented with a right-sided hy-poglossal palsy 2 days after occipital head trauma. CT showed excessive occipito-temporal and atlas pneumatization, soft tissue emphysema, right-sided opacification of mastoid air cells, and a right-sided hypoglossal canal fracture (figures 1 and 2). Hypo-glossal palsy resolved spontaneously 10 days later. Four months later, mastoid fluid collection disap-peared on CT, and other abnormalities were stable. Repetitive positive pressure phenomena (e.g., Val-salva maneuver) are often associated with cranial bone pneumatization.1,2 The preexisting cranial bone pneumatization probably placed the patient at risk for cranial bone fracture of the thinned bone in the setting of minor head trauma. AUTHOR CONTRIBUTIONS Dimitri Renard: drafting/revising the manuscript, study concept or de-sign, analysis or interpretation of data. Cornelia Freitag: study concept or design, analysis or interpretation of data. Giovanni Castelnovo: study con-cept or design, analysis or interpretation of data