frontal sinus fracture
Frontal sinus fractures are facial fractures that involve the frontal sinus, either in isolation or more commonly as part of more complex facial fractures. They can result in cosmetic deformity, functional impairment, CSF leak, and/or intracranial infection (e.g. meningitis).
Epidemiology
Frontal sinus fractures usually occur as a result of blunt trauma to the front of the face from motor vehicle accidents or assaults, although airbags have reduced the incidence of the former . As the anterior table of the frontal sinus is composed of strong bone, in the majority of cases frontal sinus fractures are associated with additional facial fractures and often with intracranial injuries . Frontal sinus fractures only account for 5-15% of all maxillofacial injuries .
Radiographic features
CT
CT of the brain with thin bone algorithm images is a routine part of the assessment of the head and neck in the setting of trauma and is ideal for the identification of fractures of the paranasal sinus. If a fracture is visualized care should be taken to assess whether the anterior table (between sinus and scalp), posterior table (between sinus and dura) or both are involved, and to note the degree of displacement . Presence of pneumocephalus, particularly if intradural (subarachnoid) is important as it increases the risks of subsequent CSF leak, meningitis and mucocoeles due to trapped mucosal elements .
Additionally, identifying involvement of the frontoethmoidal recess inferomedially is important in predicting future impaired drainage .
Treatment and prognosis
In part due to the development of endoscopic repair techniques, routine repair of frontal sinus fractures is less commonly carried out than before . Indications for treatment include cosmetic deformity (a depressed outer table fracture can be seen as an indentation of the forehead), meningitis or sinus dysfunction (e.g. development of a mucocoele).