Extensive Subcutaneous Cervical Emphysema and Pneumomediastinum Related to Mastoid Fracture: A Case Report

Introduction Subcutaneous cervical emphysema is a condition that occurs when air accumulates within subcutaneous tissues of the neck, typically due to trauma or barotrauma. In rare cases, emphysema may extend to the chest, leading to pneumomediastinum, which can cause severe complications [1]. We present a case where blunt force trauma disrupted well-pneumatized mastoid air cells resulting in extensive air dissemination. A fracture created a unidirectional air leakage valve into soft tissues that was exacerbated by increased middle ear pressure due to persistent coughing [2]. Case Presentation A 23-year-old male after sustaining head trauma during a physical assault presented with right-sided postauricular pain and transient loss of consciousness. Upon further inquiry, the patient reported a history of severe persistent coughing and rhinorrhea prior to the trauma. Physical examination: Palpable crepitation over the cervical and thoracic areas.CT revealed: A right mastoid fracture with minor displacement.Extensive subcutaneous emphysema, extending from the neck to the mediastinum.Well-pneumatized mastoid air cells bilaterally.The patient's stable condition allowed a conservative treatment approach, including pain management, cough suppression, and strict avoidance of nose blowing- activities that could exacerbate air leakage. Follow-up imaging confirmed regression of emphysema. The patient was discharged in stable condition. Discussion This case illustrates the interplay between mastoid fracture, mastoid air cell pneumatization, and increased intrathoracic pressure. The impact of trauma disrupted the integrity of the mastoid air cells, creating a pathway for air migration through fascial planes [3]. The well-pneumatized mastoid air cells likely facilitated rapid air spread, as their extensive network provided multiple escape routes. Additionally, the patient’s persistent coughing and nose blowing acted similarly to the Valsalva maneuver, increasing intrathoracic pressure and opening the Eustachian tube, allowing air to reach the middle ear cavity and the mastoid air cell system, resulting in extensive air leakage. Conclusions This case report emphasizes the clinical significance of recognizing subcutaneous emphysema as a potential complicating factor in adult cranial trauma.